Abstract
We investigate the magnetic nanoparticles hyperthermia in a non-adiabatic and radiating process through the calorimetric method. Specifically, we propose a theoretical approach to magnetic ...hyperthermia from a thermodynamic point of view. To test the robustness of the approach, we perform hyperthermia experiments and analyse the thermal behavior of magnetite and magnesium ferrite magnetic nanoparticles dispersed in water submitted to an alternating magnetic field. From our findings, besides estimating the specific loss power value from a non-adiabatic and radiating process, thus enhancing the accuracy in the determination of this quantity, we provide physical meaning to a parameter found in literature that still remained not fully understood, the effective thermal conductance, and bring to light how it can be obtained from experiment. In addition, we show our approach brings a correction to the estimated experimental results for specific loss power and effective thermal conductance, thus demonstrating the importance of the heat loss rate due to the thermal radiation in magnetic hyperthermia.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Quantitative real‐time PCR (qPCR) has become one of the most used techniques to measure gene expression. However, normalization of gene expression data against reference genes is essential, although ...these are usually used without any kind of validation. The expression of seven genes was compared in organs of Rhodnius prolixus under diverse conditions, using published software to test gene expression stability. Rp18S and elongation factor 1 (RpEF ‐1) were the most reliable genes for normalization in qPCR when gene expression in different organs was compared. Moreover, both genes were found to be the best references when transcript levels were compared in the posterior midgut of insects infected with Trypanosoma cruzi. Rp18S was also the best reference gene in the fat bodies of unfed and fed insects. By contrast, RpEF‐1 was found to be the best reference gene for comparison between posterior midguts, and RpMIP or RpActin should be used to compare gene expression in the ovaries. Although Rp18S is indicated here as the best reference in most cases, reports from the literature show that it is difficult to find an optimum reference gene. Nevertheless, validation of candidate genes to be taken as references is important when new experimental conditions are tested to avoid incorrect data interpretation.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Base‐metal sulfur liquids (mattes) play a crucial role as metasomatic agents and carriers of highly siderophile elements (HSE) within the Earth's mantle. Prior research has predominantly focused on ...sulfur‐poor metallic liquids involved in core formation scenarios. We conducted high‐pressure experiments using a multi‐anvil apparatus to investigate the effects of pressure, non‐ferrous compounds in mattes, and the mineral composition of the silicate host on matte wetting properties. Specifically, we explored conditions representing both the lithospheric (6 and 7 GPa) and sub‐lithospheric Earth's mantle (13 GPa). We characterized the experiments using the distribution of the dihedral angle in backscattered‐electron sections and the sphericity and network topology of the mattes in tomography scans. Our findings reveal distinct behaviors: while the matte in olivine‐dominated samples exhibited behaviors consistent with previous studies, such as high dihedral angle values (94° and 100°), the majorite‐bearing sample run at 13 GPa formed a disseminated network with a mean dihedral angle of 43°, below the connectivity threshold of 60°. Furthermore, in an experiment involving a garnet‐bearing silicate host, we observed a decrease in the matte's dihedral angle to 72°. Our results suggest that pressure within mafic hosts contributes to increased matte mobility in the sub‐lithospheric Earth's mantle, especially inasmuch as the stability of garnet phases is concerned. Consequently, mattes within subducted oceanic crusts may efficiently transport HSE into surrounding lithologies, while mattes within depleted, more harzburgitic lithologies and the ambient mantle may remain trapped within the silicate host at low melt fractions.
Plain Language Summary
Our study focused on how sulfur‐rich liquids percolate in Earth's mantle and carry important elements. Previous research mostly studied how metallic liquids, which are sulfur‐poor, form planetary cores. We did experiments under high pressure and high temperature to see how different factors affect the mobility of sulfur‐bearing liquids in the deep Earth's mantle. We found that the type of rock and pressure levels affect how mattes spread. When rocks contained the high‐pressure polymorph of garnet, called majorite, mattes moved differently compared to rocks that mostly contain the mineral olivine. Our results show that rocks and pressure levels influence matte movement in regions of Earth's mantle that are comprised of subducted oceanic crust. This helps us understand how elements move inside the Earth, especially when oceanic crust sinks into the mantle.
Key Points
The mobility of mattes is enhanced by majoritic garnet at sub‐lithospheric depths
The combination of 2D and 3D methods improves our understanding of liquid percolation in the Earth's mantle
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Research regarding polyphenols has gained prominence over the years because of their potential as pharmacological nutrients. Most polyphenols are flavanols, commonly known as catechins, which are ...present in high amounts in green tea. Catechins are promising candidates in the field of biomedicine. The health benefits of catechins, notably their antioxidant effects, are related to their chemical structure and the total number of hydroxyl groups. In addition, catechins possess strong activities against several pathogens, including bacteria, viruses, parasites, and fungi. One major limitation of these compounds is low bioavailability. Catechins are poorly absorbed by intestinal barriers. Some protective mechanisms may be required to maintain or even increase the stability and bioavailability of these molecules within living organisms. Moreover, novel delivery systems, such as scaffolds, fibers, sponges, and capsules, have been proposed. This review focuses on the unique structures and bioactive properties of catechins and their role in inflammatory responses as well as provides a perspective on their use in future human health applications.
Granular sludge is a promising biotechnology to treat sewage contaminated with pharmaceuticals due to its increased toxicity resistance. In this context, this study evaluated the potential of Ca
as a ...granulation precursor and how pharmaceutical compounds (loratadine, prednisone, fluconazole, fenofibrate, betamethasone, 17α-ethinyl estradiol, and ketoprofen) affect granulation. Continuous and intermittent dosages of Ca
in the presence and absence of pharmaceuticals were evaluated. The results showed that intermittent addition of Ca
reduces the time for anaerobic sludge granulation, and pharmaceuticals presence did not impair granulation. 10% of the granules presented mean diameters greater than 2.11 mm within 93 days with intermittent Ca
dosage in the pharmaceuticals' presence. In contrast, no granules higher than 2.0 mm were observed with no precursor addition. The pharmaceuticals' toxicity may have created a stress condition for the microbial community, contributing to more EPS production and a greater potential for granulation. It was also verified that pharmaceuticals' presence did not decrease organic matter, total alkalinity, and volatile fatty acids removals. The 16S rRNA gene analysis revealed taxa resistance to recalcitrant compounds when pharmaceuticals were added. Besides, the efficiency of a granular sludge bioreactor (EGSB) was evaluated for pharmaceuticals removal, and betamethasone, fenofibrate, and prednisone were effectively removed.
The continuous size downscaling of complementary metal–oxide–semiconductor (CMOS) transistors has led to the replacement of SiO
2
with a HfO
2
-based high dielectric constant (or high-
k
) oxide, and ...the polysilicon electrode with a metal gate. The approach to this technological evolution has spurred a plethora of fundamental research to address several pressing issues. This review focusses on the large body of first principles (or ab initio) computational work employing conventional density functional theory (DFT) and beyond-DFT calculations pertaining to HfO
2
-based dielectric stacks. Specifically, structural, thermodynamic, electronic, and point-defect properties of bulk HfO
2
, Si/HfO
2
interfaces, and metal/HfO
2
interfaces are covered in detail. Interfaces between HfO
2
and substrates with high mobility such as Ge and GaAs are also briefly reviewed. In sum, first principles studies have provided important insights and guidances to the CMOS research community and are expected to play an even more important role in the future with the further optimization and “scaling down” of transistors.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This work investigated the effect of the nature of dopant (Pr, Nb and Zr) on the performance of Pt supported on cerium-based oxides deposited on alumina for dry reforming of methane. in situ XRD and ...XANES analyses showed that the sample doped with Pr exhibited the highest redutibility of ceria (23%). Furthermore, the cyclohexane dehydrogenation reaction revealed that the addition of Pr improved the resistance to metal sintering during the dry reforming reaction. In the absence of doped-ceria oxide, a strong deactivation took place on Pt/Al2O3 catalyst during reaction, which was due to the absence of support reducibility and the highest Pt sintering. Among the doped-ceria samples, Pt/CePr/Al2O3 exhibited the highest activity and stability. These results were attributed to: (i) the oxygen mobility of the supports containing ceria, mainly for the sample doped with Pr, which favors the carbon removal mechanism; and (ii) the absence of Pt sintering during the reaction.
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•Pt/Al2O3 and Pt/CeM/Al2O3 (M = Pr, Nb and Zr) were tested for biogas reforming.•The addition of doped-ceria oxide to Pt/Al2O3 improved the stability of the catalyst.•Among the ceria-doped samples, Pt/CePr/Al2O3 was the most stable catalyst.•The oxygen mobility of the ceria based supports inhibited the carbon formation on Pt.•The absence of Pt sintering also contributed to the higher stability of Pt/CePr/Al2O3.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The positive Ti isotope versus SiO2‐content correlation in igneous rocks reflects the fractional crystallization of Ti‐bearing oxide minerals. However, Ti isotope variations of subduction‐related ...igneous rocks indicate that the Ti isotope compositions of their mantle sources are heterogeneous and additional mineral phases may promote Ti isotope fractionation. We have determined the Ti isotope composition of well‐characterized subduction‐related basalts, andesites and boninites. Samples from the Solomon Islands, the Troodos ophiolite in Cyprus, and Cape Vogel in Papua New Guinea show small but resolvable variations that may be related to differences in their mantle sources. Specifically, the δ49Ti of boninites (+0.109‰ to +0.168‰) is slightly higher than that of tholeiites (−0.027‰ to +0.111‰) from the same localities (Troodos in Cyprus and Cape Vogel in Papua New Guinea). Modeling suggests the partial melting of progressively depleted mantle sources where residual Cr‐spinel plays a greater role in controlling the Ti budget during partial melting. More pronounced variations in δ49Ti are clearly linked to the fractional crystallization of Ti‐oxides: Samples from Rabaul Volcanic Complex (New Britain, Papua New Guinea) show increasing δ49Ti (up to +0.373‰) with increasing Ti/V and decreasing Dy/Yb. Fractional crystallization models suggest that oxide minerals and amphibole are needed to sufficiently increase the δ49Ti of these magmas. Our study highlights that the combination of diagnostic trace element patterns and Ti isotope compositions in subduction‐related igneous rocks can be a powerful tool to constrain petrogenetic processes and to discriminate between different crystallizing mineral phases.
Plain Language Summary
Titanium isotope data obtained for basalts from various volcanic arc‐related settings show how the different minerals involved in their magmatic evolution influence their Titanium isotope composition. Coupled with trace element concentration data, magmatic processes are revealed that operate on either a large scale, such as along the arc in the 10 km range, or as very specific magma chamber processes.
Key Points
Mass‐dependent Titanium isotope variations in arc basalts originate from fractional crystallization as well as partial melting
Trace element and isotope modeling strongly suggest that amphibole fractionates Ti isotopes in addition to magnetite or ilmenite
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Since the fundamental discovery of the giant magnetoresistance many spintronic devices have been developed and implemented in our daily life (
e.g.
information storage and automotive industry). ...Lately, advances in the sensors technology (higher sensitivity, smaller size) have potentiated other applications, namely in the biological area, leading to the emergence of novel biomedical platforms. In particular the investigation of spintronics and its application to the development of magnetoresistive (MR) biomolecular and biomedical platforms are giving rise to a new class of biomedical diagnostic devices, suitable for bench top bioassays as well as point-of-care and point-of-use devices. Herein, integrated spintronic biochip platforms for diagnostic and cytometric applications, hybrid systems incorporating magnetoresistive sensors applied to neuroelectronic studies and biomedical imaging, namely magneto-encephalography and magneto-cardiography, are reviewed. Also lab-on-a-chip MR-based platforms to perform biological studies at the single molecule level are discussed. Overall the potential and main characteristics of such MR-based biomedical devices, comparing to the existing technologies while giving particular examples of targeted applications, are addressed.
An overview of state-of-the-art spintronics-based biomedical platforms at different stages of development is undertaken and examples of specific applications are discussed.
The effect of annual at-home bleaching on the color, translucency, and whiteness properties of computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic materials requires ...investigation. The aim of the present in vitro study was to evaluate the effect of simulated annual at-home bleaching (consisting of daily applications for 10 hours a day for 14 days), for up to 3 years, on susceptibility to staining (ΔE00), translucency (ΔTP00), and whiteness (ΔWID) variations and on topography of CAD-CAM monolithic materials. Disks from the Lava Ultimate (LU), Vita Enamic (VE), IPS Empress CAD (EMP), and IPS e.max CAD (EMAX) were allocated as follows: 1) nonbleached or 2) bleached with 10% carbamide peroxide. After reading the CIE L*a*b* coordinates at baseline (R0), specimens were bleached or not and subsequently immersed for a 1-year simulated period in coffee before the next reading (R1). This process was repeated two more times, resulting in R2 and R3. The ΔE00, ΔTP00, and ΔWID between R1, R2, and R3 in relation to R0 were calculated. The surface topography was analyzed by scanning electron microscopy. In general, bleaching increased the staining susceptibility of all materials when compared to the nonbleached groups and that of the LU, VE, and EMAX over the years. Bleaching decreased the translucency of the VE in all years and over the years. When compared to the nonbleached groups, bleaching decreased the whiteness of the LU and EMAX and increased the whiteness of the EMP, while the VE was not affected. In the LU, the whiteness decreased over the years in both treatments, whereas the other materials were not affected with time. All materials showed progressive topographic changes over the years. The simulated annual at-home bleaching with 10% carbamide peroxide adversely affected the topography and the optical and/or colorimetric properties of the evaluated materials.
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