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Carbon encapsulated Ni (Ni@C) nanoparticles with core/shell structure have been synthesized by levitational gas condensation (LGC) method. The methane (C[H.sub.4]) gas was used for the coating on the surface of Ni nanoparticles. The as-prepared Ni@Cs were characterized by X-ray diffraction (XRD), vibrating samples magnetometer (VSM), and transmission electron microscopy (TEM). The particles had core structure of diameter at and below 10 nm and were covered by carbon 2-3 nm thin layers. The hysteresis loop of the as-prepared Ni@Cs materials with unsaturated magnetization shows a superparamagnetic state at room temperature. Index Terms--Carbon encapsulation, levitational gas condensation (LGC), magnetic behavior, nano particle, Ni.

[Ti.sub.1-x][Fe.sub.x][O.sub.2] and [Ti.sub.1-2x][Fe.sub.x][Nb.sub.x] [O.sub.2] (x = 0.0, 0.01) powders were synthesized by the sol-gel method. X-ray diffraction patterns showed a pure anatase single phase and no different peaks other than anatase titanium dioxide were observed. Mossbauer spectra of all samples showed that the magnetically ordered and paramagnetic phases coexisted in all temperature ranges (4.2-295 K), where Fe is not metallic but in the +3 state substituting for Ti. Although the Fe/Nb co-doped samples showed more magnetically ordered phase than Fe-single-doped samples with the same amount of Fe ions in 295 K spectra, the smaller magnetic moments were observed in Fe/Nb co-doped samples. This result suggests that the Nb co-doping decreases the ferromagnetic contribution of Fe ions in Ti[O.sub.2] and increases the antiferromagnetic contribution. Index Terms--Diluted magnetic semiconductor (DMS), ferromagnetic, Mossbauer spectroscopy, titanium dioxide.

[Ti.sub.1-x] [sup.57][Fe.sub.x][O.sub.2] compounds were fabricated using the chemical solution method, and the crystal structure and ferromagnetic properties were investigated as a function of doped [sup.57]Fe concentration. X-ray diffraction patterns showed a pure anatase single phase, without any segregation of Fe into particulates within the instrumental resolution limit. Magnetic properties were characterized by vibrating sample magnetometer and Mossbauer spectroscopy with a [sup.57]Co(Rh) source. With varying [sup.57]Fe concentration, we could observe unusual magnetic phenomena in these materials. Doping [sup.57]Fe into the Ti[O.sub.2] nonmagnetic semiconductor formed magnetic properties, but the gradual increase of [sup.57]Fe concentration decreased rapidly the ferromagnetic properties rather than enhanced the ferromagnetic properties. This result reveals an interesting feature, there is a critical limit of [sup.57]Fe concentration to get ferromagnetic properties at room temperature. Index Terms--Anatase, diluted magnetic semiconductor (DMS), ferromagnetic, Mossbauer spectroscopy.

Objective: The treatment of infective endocarditis (IE) has become more complex with the current myriad healthcare-associated factors and the regional differences in causative organisms. We aimed to investigate the overall trends, microbiological features, and outcomes of IE in South Korea.Methods: A 12-year retrospective cohort study was performed. Poisson regression was used to estimate the time trends of IE incidence and mortality rate. Risk factors for in-hospital mortality were identified with multivariable logistic regression, and model comparison was performed to evaluate the predictive performance of notable risk factors. Kaplan-Meier survival analysis and Cox regression were performed to assess long-term prognosis.Results: We included 419 patients with IE, the incidence of which showed an increasing trend (relative risk 1.06, p=0.005), whereas mortality demonstrated a decreasing trend (incidence rate ratio 0.93, p=0.020). The in-hospital mortality rate was 14.6%. On multivariable logistic regression analysis, aortic valve endocarditis (OR 3.18, p=0.001), IE caused by Staphylococcus aureus (OR 2.32, p=0.026), neurological complications (OR 1.98, p=0.031), high Sequential Organ Failure Assessment score (OR 1.22, p=0.023) and high Charlson Comorbidity Index (OR 1.11, p=0.019) were predictors of in-hospital mortality. Surgical intervention for IE was a protective factor against in-hospital mortality (OR 0.25, p<0.001) and was associated with improved long-term prognosis compared with medical treatment only (p<0.001).Conclusions: The incidence of IE is increasing in South Korea. Although the mortality rate has slightly decreased, it remains high. Surgery has a protective effect with respect to both in-hospital mortality and long-term prognosis in patients with IE. [ABSTRACT FROM AUTHOR]

The derivation of the areal, peripheral and corner components of junction leakage currents in shallow p(super +)-n junctions made using quarter-micron CMOS technology is presented. The corner leakage current density of silicided junction is two times larger than the areal and peripheral densities. This shows the importance of the corner leakage element for this particular CMOS technology. It should be given due attention in shallow silicided junction as silicide is essential in ultra-large scale integration.

Melt-spun [Fe.sub.83][B.sub.9][Nb.sub.7][Cu.sub.1] alloy with ultrathin ribbon has been studied with Mossbauer spectroscopy and X-ray diffraction. The enhanced magnetic property of the flash-annealed alloy was attributed to the reduced [Alpha]-Fe phase grain size to 6 nm and the higher effective permeability and smaller magnetic core loss at 1 MHz than conventional annealed alloys. The occupied area of the nanocrystalline phase at the optimum 773 K is about 73% whereas that for conventional annealing temperature at 893 K is about 71%. The flash annealing technique was effective in improving the high-frequency soft magnetic property of nanocrystalline [Fe.sub.83][B.sub.9][Nb.sub.7][Cu.sub.1] alloy.

The effects of crystallographic change induced during the annealing process upon the magnetic properties of nanocrystalline Fe[sub 78]Al[sub 4]Nb[sub 5]B[sub 12]Cu[sub 1] alloy were investigated by using x-ray diffraction, Mo¨ssbauer spectroscopy, and macroscopic magnetometry. Special focus was concentrated on the structures of interfacial layer, which is a region between nanocrystallite and amorphous matrix. To examine the differences in the crystallographic and the magnetic properties associated with the thermal treatments, amorphous samples were annealed in two different ways, i.e., flash annealing and conventional annealing. The Mo¨ssbauer spectra were analyzed to decompose into three or four components, and revised Vincze method was used to extract the distributions of hyperfine parameters. Interfacial layers were found to have a considerable crystalline order. Flash annealing advances the crystallization process earlier than the conventional annealing. As a result, the fraction of the crystalline phase produced by flash annealing is much higher than that produced by conventional annealing performed at the same temperature. At annealing temperature of as high as 550 °C, second-stage crystallization started and crystalline Fe[sub 2]B phase was created. The deterioration in soft magnetic properties at this high annealing temperature was attributed this crystallographic change. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Summary: Background: Fear of hypoglycaemia (FOH) significantly disrupts the daily management of type 1 diabetes (T1D) and increases the risk of complications. Recent technological advances can improve glucose metrics and reduce hypoglycaemia frequency, yet their impact on FOH is unclear. This systematic review and meta-analysis (SRMA) aimed to synthesize the current literature to understand the impact of diabetes technologies on FOH in T1D. Methods: In this SRMA, we searched PubMed, Medline, Scopus, and Web of Science from inception up to May 21st, 2023 for studies assessing the effect of using real-time or intermittently scanned continuous glucose monitors (rtCGM or isCGM); insulin pumps (CSII); and their combinations on FOH as the primary outcome, measured using the Hypoglycaemia Fear Survey (HFS; including total, worries [HFS-W], and behaviours [HFS-B] scores), in non-pregnant adults with T1D. Data was extracted by the first and second authors. Results were pooled using a random-effects model based on study design (RCT and non-RCT), with subgroup analysis based on the type of technology, reported change in hypoglycaemia frequency, and duration of use. Risk of bias was evaluated with Cochrane and Joanna Briggs Institute tools. This study is registered with PROSPERO, CRD42021253618. Findings: A total of 51 studies (n = 8966) were included, 22 of which were RCTs. Studies on rtCGM and CSII reported lower FOH levels with ≥8 weeks of use. Studies on CSII and rtCGM combinations reported lower FOH levels after ≥13 weeks of automated insulin delivery (AID) use or 26 weeks of sensor-augmented pump (SAP) use. The meta-analysis showed an overall lower FOH with technologies, specifically for the HFS-W subscale. The RCT meta-analysis showed lower HFS-W scores with rtCGM use (standard mean difference [95%CI]: −0.14 [−0.23, −0.05], I2 = 0%) and AID (−0.17 [−0.33, −0.01], I2 = 0%). Results from non-RCT studies show that SAP users (−0.33 [−0.38, −0.27], I2 = 0%) and rtCGM users (−0.38 [−0.61, −0.14], I2 = 0%) had lower HFS-W. Interpretation: We found consistent, yet small to moderate, effects supporting that diabetes technologies (specifically rtCGM, SAP, and AID) may reduce hypoglycaemia-related worries in adults with T1D. Current literature, however, has limitations including discrepancies in baseline characteristics and limited, mainly descriptive, statistical analysis. Thus, future studies should assess FOH as a primary outcome, use validated surveys, and appropriate statistical analysis to evaluate the clinical impacts of technology use beyond just glucose metrics. Funding: Canadian Institutes of Health Research, Juvenile Diabetes Research Foundation Ltd.