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The current pandemic of novel coronavirus disease (COVID-19) has highlighted the importance of disinfectants. As a raw material for next-generation disinfectants, scallop shell-derived calcium oxide (CaO) has been revealed to exhibit significant virucidal and microbicidal activities and is compatible with living tissues and the environment. This minireview summarizes recent progress in the development of disinfectants from scallop shell-CaO, focusing especially on studies of clinical and daily use applications. We describe the preparation, basic characteristics, and virucidal and microbicidal activities of scallop shell-CaO disinfectants. Furthermore, their applications in the disinfection of contaminated masks and the treatment of infected wounds are briefly introduced.

Bioshell calcium oxide (BiSCaO) is derived from scallop shells and after heat treatment exhibits broad microbicidal activity. BiSCaO Water is a disinfectant prepared by collecting the aqueous layer after adding BiSCaO powder to water, is colorless and transparent, and has a pH of 12.8. We compared the utility of commercially available BiSCaO Water, ethanol, sodium hypochlorite, hypochlorous acid and hydrogen peroxide solutions as sterilization agents to enable the reuse of surgical and N95 face masks. The microbicidal efficacy of each disinfectant was evaluated using pieces of surgical and N95 face masks contaminated with normal bacterial flora. The results suggest that BiSCaO Water has excellent disinfection activity toward contaminated polypropylene masks and has minimal adverse effect on the structure of non-woven masks.

Background Scallop shell powder is called bioshell calcium oxide (BiSCaO), which is known to possess deodorizing properties and broad antimicrobial activity against various pathogenic microbes, including viruses, bacteria, spores, and fungi. Objective This study aims to investigate the applications of BiSCaO suspension cleansing in clinical situations, for instance for the prevention and treatment of infections in chronic wounds in healing-impaired patients, without delaying wound healing. Methods The bactericidal activities of 1000 ppm BiSCaO suspension; 500 ppm hypochlorous acid; 1000 ppm povidone iodine; and saline were compared to evaluate in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. Results Cleansing of the infected wounds with BiSCaO suspension daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts, in comparison to hypochlorous acid, povidone iodine, and saline. Furthermore, histological examinations showed significantly advanced granulation tissue and capillary formation in the wounds cleansed with BiSCaO suspension than in those cleansed with the other solutions. Conclusions This study suggested that the possibility of using BiSCaO suspension as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects on wound repair.

Bioshell calcium oxide (BiSCaO) exhibits deodorizing properties and broad microbicidal activity. In this study, we examined possible utility of BiSCaO Water for that purpose. BiSCaO Water was prepared by adding 10 wt% BiSCaO to clean water and gently collecting the supernatant in a bottle. The same volume of clean water was gently poured onto the BiSCaO precipitate and the supernatant was gently collected in a bottle, this process was repeated fifty times. The produced BiSCaO Water contained nanoparticles (about 400&ndash, 800 nm) composed of smaller nanoparticles (100&ndash, 200 nm), and was colorless and transparent, with a pH &gt, 12.7. In vitro assays demonstrated that BiSCaO Water eliminated more than 99.9% of influenza A (H1N1) and Feline calicivirus, Escherichia coli such as NBRC 3972 and O-157:H7, Pseudomonas aeruginosa, Salmonella, and Staphylococcus aureus within 15 min. We compared BiSCaO Water with the other microbicidal reagents such as ethanol, BiSCaO, BiSCa(OH)2 suspensions, povidone iodine, NaClO, BiSCaO dispersion and colloidal dispersion with respect to deodorization activity and microbicidal efficacy. The results showed that BiSCaO Water was a potent reagent with excellent deodorization and disinfection activities against pathogenic bacteria and viruses (including both enveloped and nonenveloped viruses).

Application of a high-velocity steam-air micromist jet spray (HVS-AMJS) with disinfectants for cleansing the skin is proposed. Low-pressure steam is mixed with compressed air in a nozzle and then sprayed onto a surface of skin or material located approximately 22 cm from the nozzle. The temperature on the sprayed surface was controlled between 40oC and 45 oC. The improved HVS-AMJS installed scattering prevention cover with tap water effectively removed normal bacterial flora (total viable count and coliform bacteria) from contaminated skin pieces and pig skin wounds. Furthermore, the cleansing efficacy increased by advanced-treating with bio-shell calcium oxide (BiSCaO), hypochlorous acid (HClO), sodium hypochlorite (NaClO), povidone iodine, or chlorhexidine gluconate. Especially, the improved HVS-AMJS combined with BiSCaO had higher bactericidal activity than when combined with other disinfectants. This study suggests that application of the HVS-AMJS with disinfectants, especially BiSCaO, may be useful for skin cleansing to prevent infection.

Bioshell calcium oxide (BiSCaO) is a scallop-shell powder heated at a high temperature. BiSCaO is composed mainly of calcium oxide and exhibits broad microbicidal properties. The aim of this study is to evaluate the disinfection and decontamination abilities of BiSCaO colloidal dispersions with that of commercially available bioshell calcium hydroxide (BiSCa(OH)2) following the formation of flocculants/precipitates under strongly alkaline conditions (pH 11.5&ndash, 12.2). Various concentrations of BiSCaO and BiSCa(OH)2 colloidal dispersions were prepared by mixing with Na-polyPO4 (PP) and Na-triPO4 (TP) as flocculating agents. The microbicidal activities, and the degree of flocculation/precipitation of trypan blue, albumin, chondroitin sulfate, heparin, non-anticoagulant heparin carrying polystyrene (NAC-HCPS), and low-molecular-weight heparin/protamine nanoparticles (LMWH/P NPs) were dependent on the pH, the average particle diameter, and the concentration of BiSCaO or BiSCa(OH)2 and of the phosphate compound. BiSCaO (average particle diameter: 6 &mu, m) colloidal dispersions (0.2 wt.%) containing 0.15 wt.% PP or TP exhibited substantially stronger microbicidal activity and flocculation/precipitation under strongly alkaline conditions. These results suggest that BiSCaO colloidal dispersions together with phosphate compounds have practical applicability for disinfection.

Silver is easily available and is known to have microbicidal effect; moreover, it does not impose any adverse effects on the human body. The microbicidal effect is mainly due to silver ions, which have a wide antibacterial spectrum. Furthermore, the development of multidrug-resistant bacteria, as in the case of antibiotics, is less likely. Silver ions bind to halide ions, such as chloride, and precipitate; therefore, when used directly, their microbicidal activity is shortened. To overcome this issue, silver nanoparticles (Ag NPs) have been recently synthesized and frequently used as microbicidal agents that release silver ions from particle surface. Depending on the specific surface area of the nanoparticles, silver ions are released with high efficiency. In addition to their bactericidal activity, small Ag NPs (

The bactericidal activity of heated bio-shell calcium oxide (BiSCaO) powder suspension (pH 12.4) , hypochlorous acid (HClO; pH 6), sodium hypochlorite (NaClO; pH 8) , povidone-iodine (Isodine solution®) , and chlorhexidine gluconate (Hibiscrub®) under organic matter contaminated environments were compared for tests conducted on wood scraps and pig skin pieces that were incubated with normal bacterial flora (total viable counts and coliform bacteria) . The test results showed that BiSCaO suspension had higher bactericidal activity than HClO and NaClO. Furthermore, more than 10-fold higher concentrations of antiseptics such as povidone-iodine and chlorhexidine gluconate were required to achieve bactericidal activity comparable to that of BiSCaO suspension. Our results demonstrate the possibility of using BiSCaO suspension under organic matter contaminated environments as a disinfectant for environmental and food hygiene applications.

Recently, there has been an increase in the number of food poisoning cases associated with histamine in food, mainly in relation to histamine in fish. Here, we investigated methods to decrease histamine levels in Japanese pilchard, Japanese horse mackerel, and chub Mackerel, stored at 10 &deg, C using various concentrations of heated scallop bioshell calcium oxide (BiSCaO) suspension, dispersion (BiSCaO + Na2HPO4), colloidal dispersion (BiSCaO + NapolyPO4), scallop shell powder (SSP) Ca(OH)2 in pure water (PW) or saline, and BiSCaO water. BiSCaO in a high alkaline pH solution chemically decomposes histamine poorly, but the partial flocculation/precipitation of histamine was observed with 1 and 0.2 wt.% BiSCaO dispersion and BiSCaO colloidal dispersion, respectively. Cleaning fish samples with BiSCaO suspension, dispersion, colloidal dispersion, or BiSCaO water remarkably reduced histamine levels and normal bacterial flora (coliform bacteria (CF) and total viable bacterial cells (TC)) after storage for four days at 10 &deg, C, while much higher histamine levels were observed after cleaning with saline. These results suggest that cleaning fish with BiSCaO dispersion, colloidal dispersion, or BiSCaO water can significantly reduce histamine levels through their bactericidal activity against histamine-producing bacteria.

Weakly acidic hypochlorous acid (HClO; 200 ppm, pH 6.5) is effective against a broad range of microorganisms. We have previously reported a study of developing antimicrobial biomaterials made up of chitin-nanofiber sheet (CNFS) -immobilized silver nanoparticles (CNFS/Ag NPs) and showed that either cleansing with HClO or covering with CNFS/Ag NPs daily for more than 7 days resulted in delayed wound healing. This study aimed to evaluate disinfection and wound healing by a combination of cleansing with HClO and covering with CNFS/Ag NPs daily for 3 days. Applying HClO + CNFS/Ag NPs daily for 3 days and then cleansing with just pure water and covering with CNFS alone daily for 9 days were performed for Pseudomonas aeruginosa-infected wounds in db/db diabetic mice. We found a significant enhancement of wound healing and a reduction of bacteria counts compared to the controls. Histological examination showed significantly advanced granulation tissue and capillary formations in the wounds on Day 12. These results suggest that limited disinfection to 3 days with HClO + CNFS/Ag NPs may be sufficient to avoid negative effects on wound repair.

Heparinoid is the generic term that is used for heparin, heparan sulfate (HS), and heparin-like molecules of animal or plant origin and synthetic derivatives of sulfated polysaccharides. Various biological activities of heparin/HS are attributed to their specific interaction and regulation with various heparin-binding cytokines, antithrombin (AT), and extracellular matrix (ECM) biomolecules. Specific domains with distinct saccharide sequences in heparin/HS mediate these interactions are mediated and require different highly sulfated saccharide sequences with different combinations of sulfated groups. Multivalent and cluster effects of the specific sulfated sequences in heparinoids are also important factors that control their interactions and biological activities. This review provides an overview of heparinoid-based biomaterials that offer novel means of engineering of various heparin-binding cytokine-delivery systems for biomedical applications and it focuses on our original studies on non-anticoagulant heparin-carrying polystyrene (NAC-HCPS) and polyelectrolyte complex-nano/microparticles (N/MPs), in addition to heparin-coating devices.

The current study investigated whether ABO blood mistyping of human biological samples is induced by soil bacteria. A total of 380 bacterial strains were isolated from 50 discrete soil samples using human blood agar, and glycosidase activity evaluated for all strains using 4-nitropheny glycosides (4-nitrophenyl n-acetyl-α-D-galactosaminide, 4-nitrophenyl-α-D-galactopyranoside, 4-nitrophenyl-α-L-fucopyranoside) as substrates. Thirteen strains possessed α-galactosidase activity, and 16S rRNA sequence analysis revealed a close relatedness to the genus Bacillus. An indirect competitive enzyme-linked immunosorbent assay confirmed seven strains exhibited type B antigen degradation activity. These results demonstrated that 1.8% of the bacteria isolated from soil, were Bacillus sp., possessed galactosidase activity, and had the potential to cause ABO blood mistyping.

The positive tone resist consisted of methyl-α-chloroacrylate (ACM) and α-methylstyrene (MS) has higher sensitivity and higher dry etching resistance than poly (methylmethacrylate) (PMMA) due to the presence of a chlorine atom and a phenyl group. Copolymers consisted of ACM and p-chloro-α-methylstyrene (PCMS), where the additional chlorine atom is introduced in phenyl group compared with ACM-MS resist are synthesized and their exposure characteristics are investigated. ACM-PCMS resist with the ACM:PCMS composition ratio of 49:51 indicates the high solubility for amyl acetate developer. As the ACM composition ratio increases, the solubility of ACM-PCMS resist is suppressed. In both ACM-PCMS and ACM-MS resists, the sensitivity decreases while the contrast increases with increasing ACM ratio. When the composition ratio of ACM:PCMS is 69:31, 100/100 nm line and space pattern having a good shape is obtained at 120 μC/cm2 which is comparable to the required exposure dose for conventional ACM-MS resist with ACM:MS=50:50. Dry etching resistance of ACM:PCMS resists for Ar gas is also presented.

We developed an indirect competitive enzyme-linked immunosorbent assay (ELISA) for the detection of ABO blood group antigens in human samples; in particular for blood stains. ABO blood group antigens conjugated to polyacrylamide were used for immobilized antigen. ABO blood group antigens were extracted from blood stains using a novel method involving pre-incubation with proteinase K (PK), followed by heat treatment. The extracts (analytes) were combined with either anti-A or -B monoclonal antibodies (mAbs), and added directly to the antigen-coated wells. The anti-A and -B mAbs were captured by either ABO blood group antigens present in the analyte or by the immobilized blood group antigens. Peroxidase-conjugated anti-mouse IgM antibody was used to detect anti-A and -B mAbs complexed with immobilized blood group antigens, and a colorimetric reaction using o-phenylenediamine/H2O2 used for its measurement. The ELISA developed in this study was able to detect blood group antigens in blood, saliva and blood stains. The detection limit for unknown blood, saliva and blood stain were determined as 1:200, 1:32 and 1:16. Overall the ABO blood grouping ELISA can be used with relative ease for the high throughput screening of biological samples for the detection of ABO blood group antigens.

In this study, we examine exposure characteristics of a positive tone electron beam resist consisting of methyl α- chloroacrylate and α-methylstyrene by changing the development process conditions. 25/25 nm and 30/30 nm line-andspace (L/S) patterns (design value) are developed in amyl and heptyl acetates. The resist patterns developed at 0oC for 120 s show the better shapes having the vertical sidewalls than those developed at 22 °C for 60 s. The dose margins of pattern formation for 0°C development become wider, although the sensitivities are lower. The effect of post exposure baking (PEB) on exposure characteristics is also investigated. Adding PEB process performed at 120°C for 2 min, the dose margin also becomes wider although the sensitivity is lower. 20/20 nm L/S patterns are fabricated by using PEB and/or 0°C development. Though the required exposure dose is larger, the resist pattern is improved by PEB and/or 0°C development. The formation of 35 nm pitch pattern is also presented.

Scallop-shell powder (SSP) heated at high temperature exhibits high pH and broad antimicrobial activity. Bioshell calcium oxide (BiSCaO) is an SSP composed mainly of calcium oxide. It is poorly water-soluble under alkaline conditions and the generated precipitate can plug spray nozzles. The aim of this study was to establish that BiSCaO dispersion caused no significant CaO loss and plugging of spray nozzles, and to evaluate its deodorization and microbicidal abilities and its ability to reduce the concentrations of NO2&minus, and NO3&minus, BiSCaO dispersions were prepared by mixing various concentrations of BiSCaO suspension, while phosphate compounds such as Na3PO4, Na2HPO4 or NaH2PO4 and the pH, average diameter, zeta potential, and form of the compounds with cryo-SEM were evaluated. We evaluated deodorization using tainted pork meat and microbicidal efficacy using contaminated suspension with normal bacterial flora. The concentration of NO2&minus, after mixing BiSCaO dispersion and pure water containing a high proportion of NO2&minus, were measured. BiSCaO dispersion formed with Na2HPO4, whose ratio to BiSCaO was 60%, showed a high pH (&gt, 12), a small particle diameter (&gt, 181 nm) and was stable for seven days. The BiSCaO dispersion showed higher deodorization and microbicidal activities than SSP-Ca(OH)2, which was mainly composed of Ca(OH)2. BiSCaO, but not SSP-Ca(OH)2, could reduce the concentration of NO2&minus, by more than 90% within 15 min. We developed a stable BiSCaO dispersion, and it had high deodorization and microbicidal efficacy. These activities of BiSCaO might result from the high pH caused by CaO hydration and a reduction activity causing active radical species.

We report the magnetic properties of Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O, a high-entropy oxide with a rocksalt structure, and the influence of substitutions on these properties. From the magnetic susceptibility and neutron diffraction measurements, we found that this compound exhibits long-range magnetic order below 120 K despite the substantial structural disorder. Other rocksalt-type high-entropy oxides with various chemical substitutions were found to host either an antiferromagnetic order or spin-glass state depending on the amount of magnetic ions. The presence of magnetic order for such a disordered material potentially provides a route to explore exotic magnetic properties and functions.

The sensitivity and the resolution are affected by not only the nature of the resist such as a chemical structure and a molecular weight but also the developing process such as a developer molecular size. Exposure characteristics of positive-tone polymer resists having various molecular weights (Mw’s) ranging from 60 k to 500 k are investigated using different ester solvents as a developer. The line-and-space (L/S) patterns are exposed by the electron beam writing system with an acceleration voltage of 50 kV and the samples are developed by amyl acetate, hexyl acetate and heptyl acetate. The pattern shape becomes better and the surface of the resist also becomes smoother with increasing developer molecular size, though the exposure dose required for the formation of the L/S pattern increases. The dose margin of pattern formation is also wider in all the resists having the different molecular weights. The dissolution in the unexposed portions of the 60k-Mw resist for heptyl acetate is reduced significantly compared with those for amyl acetate and hexyl acetate. The improvement of the pattern shape and the increasing of dose margin are remarkable in the low molecular weight resist. The 3σ of line width roughness tends to be smaller in the higher molecular weight resist and with the larger molecular size developer. Exposure experiment of the 35 nm pitch pattern using the 500k-Mw resist developed at the room temperature is presented.

Higher resolution is eagerly requested to the electron beam resist for the next generation photomask production as well as higher sensitivity. The performance of a polymer resist is mainly characterized by its chemical structure and molecular weight. Positive tone polymer resists with various molecular weights ranging from 60 k to 500 k are synthesized and the molecular weight dependence on exposure characteristics is examined by fabricating line-and-space patterns. The molecular weight dependence of sensitivity for amyl acetate developer is small in the molecular weight range in this study. In a low molecular weight resist, the cross-section profile of the resist pattern becomes rounder and then the disconnections are observed in the 20-nm line-and-space pattern. Although the pattern width change by changing the exposure dose for each resist is quite similar, the exposure dose margin of pattern formation becomes wider with the higher molecular weight. The line width roughness is smaller in a high molecular weight resist than in a low molecular weight resist. The shift amount of the pattern width from the design value for various line-and-space patterns and the dry etching resistance to CF 4 plasma are also presented.

The Nernst effect in metals is highly sensitive to two kinds of phase transition: superconductivity and density-wave order. The large positive Nernst signal observed in hole-doped high-Tc superconductors above their transition temperature Tc has so far been attributed to fluctuating superconductivity. Cyr-Choiniere et al. report that in some of these materials the large Nernst signal is in fact caused by stripe order, a form of spin/charge modulation that causes a reconstruction of the Fermi surface. In LSCO doped with Nd or Eu, the onset of stripe order causes the Nernst signal to go from small and negative to large and positive. The Nernst effect in metals is sensitive to superconductivity and density-wave order. The large positive Nernst signal observed in hole-doped high-transition-temperature superconductors has been attributed to fluctuating superconductivity but Olivier Cyr-Choiniere and colleagues report that the Nernst signal can be caused by stripe order. In LSCO doped with Nd or Eu, the onset of stripe order causes the Nernst signal to go from small and negative to large and positive. The Nernst effect in metals is highly sensitive to two kinds of phase transition: superconductivity and density-wave order1. The large, positive Nernst signal observed in hole-doped high-Tc superconductors2 above their transition temperature (Tc) has so far been attributed to fluctuating superconductivity3. Here we report that in some of these materials the large Nernst signal is in fact the result of stripe order, a form of spin/charge modulation4 that causes a reconstruction of the Fermi surface5. In La2-xSr x CuO4 (LSCO) doped with Nd or Eu, the onset of stripe order causes the Nernst signal to change from being small and negative to being large and positive, as revealed either by lowering the hole concentration across the quantum critical point in Nd-doped LSCO (refs 6–8) or by lowering the temperature across the ordering temperature in Eu-doped LSCO (refs 9, 10). In the second case, two separate peaks are resolved, respectively associated with the onset of stripe order at high temperature and superconductivity near Tc.

We performed DNA typing for D1S80, HLADQA1, TH01 and PM using the butts of 100 cigarettes that were smoked by ten different individuals (ten cigarettes per individual). The results obtained from DNA typing for D1S80 agreed with the results obtained using bloodstains in 76 cigarette butt samples. Sixteen samples produced false results, showing the loss of the longer allelic hetero-band. When examined using agarose gel electrophoresis, high-molecular weight DNA was not observed in these samples. The same results were also observed for buccal swab samples and saliva stains obtained from the same individuals. In the remaining eight cigarette butt samples, PCR products were not detected. The results obtained from DNA typing for TH01, HLADQA1 and PM agreed with the results obtained using bloodstains in 90 samples. In the remaining ten samples of a specific kind of cigarette (Marlboro), the PCR products were not detected. The extracts from the ends of the Marlboro cigarettes were stained yellow. When the DNA extracted from Marlboro cigarette butts was treated with Microcon-100 (amicon) or SizeSep 400 Span Columns (Amersham Pharmacia Biotech), PCR products could be detected. When PCR amplification was performed after adding extracts from the ends of unsmoked Marlboro cigarettes to DNA extracted from bloodstains, PCR products could not be detected. The present data indicate that the degradation of high-molecular weight DNA and the inhibition of PCR by dyes of the cigarette end should be kept in mind when performing DNA typing using cigarette ends.

We investigated the quality and quantity of DNA in sera obtained from 16 cadavers who were left at room temperature or placed in a refrigerator for cadavers within 3 days of their death. The causes of death were as follows: asphyxia, 4; hemorrhage, 4; fire, 3; cold, 1; subdural bleeding, 1; sepsis, 1; cerebral contusion, 1; and pulmonary thromboembolism, 1. When examined using agarose gel electrophoresis, the samples from the victims who died from sepsis and pulmonary thromboembolism exhibited smear patterns, while the other samples exhibited ladder patterns. The size of each band was an integer multiple of approximately 180 bp, considered to be characteristic of apoptosis. The DNA concentration in the cadavers' sera ranged from 3.0 to 258.9 ng/ml. DNA types (D1S80, HLADQA1, TH01, and PM) were determined for all the samples except for the sample from the victim who died from sepsis. The detected types were the same as those obtained from paired bloodstain samples, except for in the asphyxia victim. D1S80 typing of the serum sample from the asphyxia victim showed the loss of the longer allelic hetero-band. These results suggest that the quantity of DNA in serum from cadavers is sufficient for DNA typing, but that the degradation of DNA may proceed quickly, depending on the temperature of the area in which the cadaver is left as well as the pathological conditions that the victim had experienced.

We report the discovery of a family of ternary platinum phosphides $A{\mathrm{Pt}}_{3}\mathrm{P}$ ($A=\mathrm{Ca}$, Sr, and La), which crystallize in an antiperovskite-based structure closely related to that of the heavy fermion superconductor ${\mathrm{CePt}}_{3}\mathrm{Si}$. All three phosphides showed superconductivity at low temperatures and the highest critical temperature ${T}_{c}=8.4\text{ }\text{ }\mathrm{K}$ was observed for ${\mathrm{SrPt}}_{3}\mathrm{P}$. The analysis of specific heat $C(T)$ for ${\mathrm{SrPt}}_{3}\mathrm{P}$ shows clear evidence for very strong coupling $s$-wave superconductivity with a large ratio between superconducting gap ${\ensuremath{\Delta}}_{0}$ and ${T}_{c}$, $2{\ensuremath{\Delta}}_{0}/{k}_{B}{T}_{c}\ensuremath{\sim}5$, and the presence of low-energy phonons. The presence of multiple Fermi surface pockets was inferred from the nonlinear magnetic field dependence of Hall resistivity, which we argue might play a role in realizing the strong coupling of charge carriers with the low-lying phonons.

We report the discovery of magnetic memory effect in cation-deficient iron sulfide Fe1−xS. This nonstoichiometric sulfide shows a transition from a ferrimagnet to an antiferromagnet induced by an order-disorder transition of cation defects. The magnetic properties of Fe0.92S, at the critical composition for the order-disorder transition, were reliably controlled by the use of appropriate heat treatments; the slow-cooled sample showed ferrimagnetism with a spontaneous magnetization, while the quenched samples displayed superparamagnetic behavior without hysteresis. We propose that this material can be used as part of a nonvolatile phase-change memory device.