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This randomized trial of fractionation after breast reconstruction (FABREC) sought to compare quality-of-life (QOL) and clinical outcomes of hypofractionated (HF) vs. conventionally-fractionated (CF) postmastectomy radiation therapy (PMRT) in the setting of immediate prosthetic reconstruction. Between 3/2018 and 11/2021, 400 patients at 18 centers with Stage 0-III breast cancer and immediate placement of tissue expander (TE) or implant (I) after mastectomy were randomized 1:1 to HF or CF photon PMRT. Respective doses in the two arms were 42.56 Gy/16 fractions to the chest wall (CW), with or without axillary/supraclavicular lymph node (LN) radiation (39.9 Gy/15 fractions) and 50 Gy in 25 fractions to CW (46-50 Gy to axillary LNs). A boost was not permitted; bolus was used at physician discretion. CW toxicity was defined as any grade ≥3 adverse event (CTCAE) after PMRT initiation. Patients were censored at study withdrawal or at diagnosis of distant recurrence. Participants completed QOL instruments (FACT-B, BREAST-Q, Lymph-ICF) at baseline, 6, 12 and 18-months from PMRT initiation. Questions regarding financial burden were included with the 6-month survey. Primary endpoint of the study was improvement in the Physical Well-Being (PWB) domain of FACT-B at 6 months with pre-specified stratification by age (younger than 45 vs. 45 years or older). QOL scores were compared using Student's t-test. Median follow-up for the 385 patients analyzed was 31.8 months (range, 6.9-54.4); median age was 47.0 years (range, 23-79). Preoperative chemotherapy was used in 67.8% and preoperative endocrine therapy (ET) in 21.5% of the cohort. There were 16 distant (8 in each arm), and 2 local-regional (1 in each arm) recurrences. CW toxicity occurred in 35 patients (19 HF, 16 CF, p=0.58) at medians of 3.4 and 4.8 months after RT initiation in the HF and CF arms, respectively (p=0.82). Post-operative infection before RT (HR=3.31, p=0.03), irradiation of TE vs I (HR=7.74, p=0.046), preoperative endocrine therapy (HR=3.45, p=0.0007) and number of LNs removed (HR=1.06/node, p=0.02) were significant for developing CW toxicity on multivariate analysis, while fractionation was not (HF HR=1.19, p=0.63). There was no significant difference in overall change in PWB scores at 6 months between the two treatment arms (p=0.71) or separately in younger (p=0.15) and older cohorts (p=0.27). However, HF patients younger than 45 were less bothered by side-effects of treatment (p=0.045) and nausea (p=0.02) vs. CF patients younger than 45. Among patients who took unpaid time off from work during treatment (n=51), those receiving HF required fewer hours off than those receiving CF (73.7 vs. 125.8, p=0.046). Physical well-being and overall toxicity profile of HF PMRT were comparable between HF and CF PMRT. HF was associated with better 6-month QOL in some domains among younger patients. Our early results support the use of HF PMRT in the setting of TE- or implant-based breast reconstruction. [ABSTRACT FROM AUTHOR]

For a two-group comparative study, a stratified inference procedure is routinely used to estimate an overall group contrast to increase the precision of the simple two-sample estimator. Unfortunately, most commonly used methods including the Cochran-Mantel-Haenszel statistic for a binary outcome and the stratified Cox procedure for the event time endpoint do not serve this purpose well. In fact, these procedures may be worse than their two-sample counterparts even when the observed treatment allocations are imbalanced across strata. Various procedures beyond the conventional stratified methods have been proposed to increase the precision of estimation when the naive estimator is consistent. In this paper, we are interested in the case when the treatment allocation proportions vary markedly across strata. We study the stochastic properties of the two-sample naive estimator conditional on the ancillary statistics, the observed treatment allocation proportions and/or the stratum sizes, and present a biased-adjusted estimator. This adjusted estimator is asymptotically equivalent to the augmentation estimators proposed under the unconditional setting. Moreover, this consistent estimation procedure is also equivalent to a rather simple procedure, which estimates the mean response of each treatment group first via a stratum-size weighted average and then constructs the group contrast estimate. This simple procedure is flexible and readily applicable to any target patient population by choosing appropriate stratum weights. All the proposals are illustrated with the data from a cardiovascular clinical trial, whose treatment allocations are imbalanced. [ABSTRACT FROM AUTHOR]

Ferromagnetic layered structure has been made at sub-surface of the antiferromagnetic FeRh bulk samples by high energy He ion beam irradiation. In accordance with the Transport of Ions in Matter simulation, such ion beam can effectively deposit the elastic collision energy in several lm regions in the depth from the surface. Measurement with a superconducting quantum interference device reveals the irradiated samples to be ferromagnetic. Assuming that only the part the energy deposited can be modified to be ferromagnetic, the corresponding irradiation induced magnetization is consistent with the data that we previously reported. On the other hand, the X-ray magnetic circular dichroism (XMCD) spectra for the irradiated samples are totally unchanged as those for the unirradiated samples. Since XMCD signal in total emission yield method is considered to be surface sensitive with a typical probing depth of several nm, the surface magnetic state is maintained to be antiferromagnetic. By utilizing these phenomena, three-dimensional magnetic patterning of FeRh can be realized, which may potentially be used for future magnetic exchange device application such as nano-scale sensors and memories. [ABSTRACT FROM AUTHOR]

A method for fabricating adhesively bonded joints with graded properties along the bond-line was proposed. By utilizing two types of acrylic adhesives, one hard and the other soft, the properties of the mixture were changed by controlling the mixing ratio. An applicator for the adhesives was developed and used for the experiments, in which property-graded adhesive layers were actually produced. The properties, i.e., stress-strain curves at various points of the property-graded adhesive layer, were experimentally measured, and the validity of the proposed method was confirmed. The Young's moduli at multiple points of the adhesive layer changed from 34.7 MPa to 634 MPa by changing the mixing ratio of the adhesives. [ABSTRACT FROM AUTHOR]

Physiological constraints can limit thermal niche breadth in organisms, particularly for small-bodied ectotherms. Daily temperature fluctuations often surpass annual (seasonal) temperature variation in the tropics, suggesting diel temperature cycles could drive thermal specialization by individuals that are active at different times of the day. We used foraging workers of the Neotropical ant Ectatomma ruidum to assess whether diurnally and nocturnally active workers differed in thermal tolerance. We compared critical thermal maxima (CT) of nocturnal and diurnal foraging workers to explore thermal niche specialization over the diel cycle. We predicted that diurnally active workers would have higher CT because they occupy a warmer thermal niche. As predicted, diurnal foragers exhibited significantly higher CT (mean 1.1 °C difference) than nocturnal foragers. Diurnal and nocturnal foragers were similar in body size, and there was no relationship between worker size and CT. We discuss possible mechanisms for this pattern, and the implications of within- versus between-colony differences in CT. [ABSTRACT FROM AUTHOR]

Background: The prevalence of Helicobacter pylori infection in Crohn's disease (CD) patients was investigated to determine whether the presence and severity of gastroduodenal lesions were related to H. pylori infection.Methods: Infection rates were compared between CD group (n = 90) and the control group (n = 525). Correlations between endoscopically detected lesions and H. pylori positive rates were investigated. The relationship between drug therapy and the prevalence of H. pylori infection was also analyzed.Results: H. pylori-positive rate of the 90 CD patients attending our clinic was 16.7%, significantly lower than the rate in healthy controls (40.2%) (P = 0.0001). The involvement of H. pylori infection in the gastroduodenal lesions of CD patients was also examined. The prevalence of gastroduodenal lesions in all CD patients was high, 92.2%. The lesions observed included ulcers, erosion, and "bamboo joint-like lesions" of the stomach, and ulcers, erosion, stenosis, and elevated lesions of the duodenum. None of these lesions were found to be related to H. pylori infection. However, H. pylori infection was found to exacerbate gastric ulcers (P = 0.036). The analysis of a possible relationship between a history of drug therapy and the low prevalence of H. pylori infection in CD patients showed that the prevalence of H. pylori infection was significantly lower in patients who had received antibiotics for 2 weeks or more (P = 0.002).Conclusions: The results suggest that H. pylori infection is essentially unrelated to the gastroduodenal lesions observed in CD. It seems likely, however, that H. pylori infection may exacerbate gastric ulcers and that H. pylori can be eradicated by prolonged use of antibiotics. [ABSTRACT FROM AUTHOR]