Various parameters in the structural features of the aluminum substituted barium hexagonal ferrite particles BaAlxFe12−xO19 with 0≤x≤3.5 which were prepared by the solid state reaction method have ...been studied. The infrared transmission spectrum was measured in the wave number region 5000–200cm−1 at room temperature. The results were interpreted in terms of the vibrations of the isolated molecular units in such a way to preserve the tetrahedral and octahedral clusters of metal oxides in the barium aluminum hexagonal ferrites. The infrared features are assigned to Fe–O and Ba–O bonds in M-type hexagonal ferrite (BaFe12O19) molecules. Also, the results explain the structural model, based on the effect of aluminum substitution “Al–O bond”. On the other hand, the magnetic behavior of the samples was studied using the vibrating sample magnetometer technique. The saturation magnetization (Ms) and magneton number (nB) decrease with increasing Al3+ substitution from 61.2 to 28.9emu/g and from 12.2 to 5.3µB respectively. Also, all samples were characterized using X-ray diffraction and the values of grain size, microstrain and dislocation density of all samples were calculated. The dielectric parameters and ac conductivity measurements were performed within a temperature range 293–493K. The ac conductivity showed a linear relation with the frequency power law with an exponent s≈0.69–0.14 for BaFe12O19. It decreases with increasing temperature, indicating that the heterogeneous structures increase. While the dielectric constant (ε′) and the dielectric loss (ε″) decrease with increasing Al substitution.
An International Ki67 Reproducibility Study POLLEY, Mei-Yin C; LEUNG, Samuel C. Y; GOWN, Allen M ...
JNCI : Journal of the National Cancer Institute,
12/2013, Letnik:
105, Številka:
24
Journal Article
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In breast cancer, immunohistochemical assessment of proliferation using the marker Ki67 has potential use in both research and clinical management. However, lack of consistency across laboratories ...has limited Ki67's value. A working group was assembled to devise a strategy to harmonize Ki67 analysis and increase scoring concordance. Toward that goal, we conducted a Ki67 reproducibility study.
Eight laboratories received 100 breast cancer cases arranged into 1-mm core tissue microarrays-one set stained by the participating laboratory and one set stained by the central laboratory, both using antibody MIB-1. Each laboratory scored Ki67 as percentage of positively stained invasive tumor cells using its own method. Six laboratories repeated scoring of 50 locally stained cases on 3 different days. Sources of variation were analyzed using random effects models with log2-transformed measurements. Reproducibility was quantified by intraclass correlation coefficient (ICC), and the approximate two-sided 95% confidence intervals (CIs) for the true intraclass correlation coefficients in these experiments were provided.
Intralaboratory reproducibility was high (ICC = 0.94; 95% CI = 0.93 to 0.97). Interlaboratory reproducibility was only moderate (central staining: ICC = 0.71, 95% CI = 0.47 to 0.78; local staining: ICC = 0.59, 95% CI = 0.37 to 0.68). Geometric mean of Ki67 values for each laboratory across the 100 cases ranged 7.1% to 23.9% with central staining and 6.1% to 30.1% with local staining. Factors contributing to interlaboratory discordance included tumor region selection, counting method, and subjective assessment of staining positivity. Formal counting methods gave more consistent results than visual estimation.
Substantial variability in Ki67 scoring was observed among some of the world's most experienced laboratories. Ki67 values and cutoffs for clinical decision-making cannot be transferred between laboratories without standardizing scoring methodology because analytical validity is limited.
The present research concerns the synthesis of a mesoporous composite characterized with high surface area and superior adsorption capacity in order to investigate its efficacity in removing ...hazardous and harmful dyes molecules from water. The synthesized mesoporous composite, MgO/g-C3N4 (MGCN), was successfully prepared through the sonication method in a methanolic solution followed by an evaporation and a calcination process. The configuration, crystalline phase, surface properties, chemical bonding, and morphological study of the fabricated nanomaterials were investigated via XRD, BET, FESEM, HRTEM, XPS, and FTIR instrumentation. The obtained nanomaterials were used as sorbents of Congo Red (CR) and Basic Fuchsin (BF) dyes from aqueous solutions. Batch elimination experimental studies reveal that the elimination of CR and BF dyes from an aqueous solution onto the MGCN surface was pH-dependent. The highest removal of CR and BF pollutants occurs, respectively, at pH 5 and 7. The absorptive elimination of CR and BF dyes into the MGCN surface was well-fitted with a pseudo-second-order kinetics and Langmuir model. In this concern, the maximum nanocomposite elimination capacity for CR and BF was observed to be 1250 and 1791 mg g−1, respectively. This investigation confirms that MGCN composite is an obvious and efficient adsorbent of CR, BF, and other organic dyes from wastewater.
•MgO/g-C3N4 Mesoporous was successfully synthesized by the sonication method.•The obtained MgO/g-C3N4 has shown interesting properties such as a high surface area. .•The obtained mesoporous were used for the removal of both Congo Red and Basic Fuchsin. .•An efficient removal for both dyes has been recorded by this mesoporous.
Abstract The American College of Cardiology third decennial Professional Life Survey was completed by 2,313 cardiologists: 964 women (42%) and 1,349 men (58%). Compared with 10 and 20 years ago, ...current results reflect a substantially lower response rate (21% vs. 31% and 49%, respectively) and an aging workforce that is less likely to be in private practice. Women continue to be more likely to practice in academic centers, be pediatric cardiologists, and have a noninvasive subspecialty. Men were more likely to indicate that family responsibilities negatively influenced their careers than previously, whereas women remained less likely to marry or have children. Men and women reported similar, high levels of career satisfaction, with women reporting higher satisfaction currently. However, two-thirds of women continue to experience discrimination, nearly 3 times the rate in men. Personal life choices continue to differ substantially for men and women in cardiology, although differences have diminished.
The applications of bioactive compounds from medicinal plants as therapeutic drugs are largely increasing. The present study selected the bioactive compounds from
(
) and
(
) to assess their ...phytochemicals, proteins, and biological activity. The plant material was collected, and extraction performed as per the standard procedure. Qualitative analysis was undertaken, and identification of functional organic groups was performed by FTIR and HPLC. Antibacterial, anticancer, antioxidant, antihyperglycemic, antihyperlipidemic, and inhibition kinetics studies for enzymes were performed to assess the different biological activities. Flavonoids and phenols were present in a significant amount in both the selected plants.
showed significant antimicrobial activity against
,
, and
, with minimum inhibition zones (MIZ) of 24, 22, and 20 mm, respectively.
strongly inhibited all the tested pathogenic bacteria with maximum and minimum MIZ of 32 and 17 mm.
silver nanoparticles also exhibited potent antimicrobial activity. Both extracts showed substantial antioxidant, antihyperlipidemic, antidiabetic, anticancer (MCF-7), and anti-urease (antiulcer) properties. To conclude, these plants can be used to treat hyperlipidemia, diabetes, cancer, and gastrointestinal ulcers. They can also serve as antimicrobial and antioxidant agents. Thus, the studied plants must be exploited cost-effectively to generate therapeutic drugs for various diseases.
The phase composition, mechanical properties, and superplastic deformation behavior of a novel Al-4.7Cu-1.6Y-0.3Zr alloy were analyzed. The precipitation of Al3(Zr,Y) dispersoids was observed during ...a homogenization treatment. The precipitates have an L12 structure and a mean size of 17 and 19 nm at 540 and 590 °C, respectively. The sheets exhibit a yield strength of 292 MPa, an ultimate tensile strength of 320 MPa, and an elongation of 5.3% after simple thermomechanical treatment and annealing at 100 °C. The Al-4.7Cu-1.6Y-0.3Zr alloy exhibits superplasticity with m > 0.4 and elongation of 300–400% within a temperature range of 550–580 °C and a strain rate range of 1 × 10−4 to 1 × 10−3 s−1.
•Intermetallic particles of Al4Si4Yb/Al10Si4Yb and Al15Cu2Si2Gd phases were identified.•Due to the addition of Zr- and Yb- or Gd in alloys, YS is increased by 50–60 MPa.•Calculation size the ...dispersoids in the investigated alloys should be with of 20–40 nm.•The compression YS significantly increased in the rare earth metals doped alloys.
The microstructure and properties of the Al-5Si-1.3Cu-0.4 Mg-0.15Zr alloys with Yb or Gd additives were investigated. Al4Si4Yb/Al10Si4Yb and Al15Cu2Si2Gd eutectic phases were identified in the investigated alloys. The compression YS at room temperature and 200 °C significantly increased in the rare earth metals doped alloys in the quenched and aged state.
Abstract Although historically the intra-aortic balloon pump has been the only mechanical circulatory support device available to clinicians, a number of new devices have become commercially ...available and have entered clinical practice. These include axial flow pumps, such as Impella® ; left atrial to femoral artery bypass pumps, specifically the TandemHeart; and new devices for institution of extracorporeal membrane oxygenation. These devices differ significantly in their hemodynamic effects, insertion, monitoring, and clinical applicability. This document reviews the physiologic impact on the circulation of these devices and their use in specific clinical situations. These situations include patients undergoing high-risk percutaneous coronary intervention, those presenting with cardiogenic shock, and acute decompensated heart failure. Specialized uses for right-sided support and in pediatric populations are discussed and the clinical utility of mechanical circulatory support devices is reviewed, as are the American College of Cardiology/American Heart Association clinical practice guidelines.
The increase in severe acute respiratory syndrome SARS-CoV-2 has invariably affected medical professionals in their training, academic and professional development. The present study was an ...interventional descriptive study aimed at reducing the risk of exposure to COVID-19 and enabling physical attendance to the practical session for applied medical students by establishing and implementing a safety strategy. The adopted safety strategy has eight conditions and 50 requirements. Compliance with the safety strategy along with the serological diagnosis of COVID-19 was used as a key performance indicator for assessing the efficiency of the safety strategy. A total of 197 students were enrolled at the beginning of the study. The overall results showed that 78.1% of the respondents strictly followed the protocol, 14.5% of the individuals partially responded to the protocol and 7.4% of the individuals did not respond to the protocol. Twenty-two (12.6%) out of the 175 participants who completed the study had positive COVID-19 during the study period, whereas the remaining 153 participants (87.4%) appeared to be healthy. The serological results showed that 68 (38.9%) and 66 (37.7%) individuals of the study population had positive IgM+IgA and IgG of COVID-19, respectively; the majority of the participants who developed antibodies did not show symptoms and appeared to be healthy during the study. The physical distancing condition was the only condition that displayed a significant relationship with seropositive IgM+IgA. The compiling of standardized protocols along with serological diagnoses can be an effective tool in measuring the effectiveness of safety protocol and reducing the risk of exposure to COVID-19.
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