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Abstract Amidst the global COVID-19 pandemic, telework (remote work) has become a widespread practice adopted by companies worldwide. However, Japan has notably maintained a low rate of telework implementation, suggesting cultural factors hindering its adoption. This study aimed to elucidate the antecedents and consequences of teleworking in Japan. Leveraging the natural experiment created by the COVID-19 pandemic, we addressed two key questions: (1) What socio-psychological factors in Japanese workplaces were important for implementing telework in the first place? and (2) How did the implementation of telework subsequently influence socio-psychological factors in these workplaces? Employees from various Japanese companies completed three waves of an online survey before and during the pandemic. Results showed that telework was more likely to be implemented in organizations characterized by a meritocracy. Results also showed that the implementation of telework demonstrated no measurable negative effects but instead increased levels of independence, organizational commitment, and perceived hierarchy mutability.

Platinum metallization of polyethylene terephthalate (PET) textile is realized by a supercritical carbon dioxide catalyzation process using palladium (II) hexafluoroacetylacetonate as the source of Pd catalyst, and ε-caprolactam as an additive. A commercially available Pt electroless plating solution is used to deposit Pt on the catalyzed PET textile. Surface morphology of the Pt metallized PET textile changes from granular particle to plate-like morphology when the Pt deposition time increases from 1 to 40 min. The Pt layer thickness reaches 270 nm, 580 nm, and 780 nm after 20 min, 60 min and 240 min, respectively, of the Pt deposition time. The Pt metallized PET textile prepared with 240 min of the Pt deposition time shows the lowest electrical resistance at 0.4 Ω, and the electrical resistance merely increases to 0.7 Ω and 1.0 Ω after one and two times, respectively, of a tape adhesion test.

The Intex laterite deposit in Mindoro, Philippines is derived from the weathering of the ultramafic rocks under a tropical climate. This study investigates the several types of serpentines and the effect of the degree of chemical weathering of ultramafic rocks and laterites on the enrichment of Ni in the deposit. The five types of serpentines are differentiated based on their textural features and Raman spectral data. Type I, type II, type III, and type IV serpentines contain a low amount of NiO (average 0.15 wt%), and their formation is linked to the previous exhumation of the ultramafic body. Conversely, type V serpentines show the highest NiO contents (average 1.42 wt%) and have the composition of serpentine-like garnierites, indicating a supergene origin. In the limonite horizon, goethite is the main ore mineral and shows high NiO contents of up to 1.68 wt%, whereas the Mn-oxyhydroxides (i.e., asbolane and lithiophorite–asbolane intermediate) display substantial amounts of CoO (up to 11.3 wt%) and NiO (up to 15.6 wt%). The Ultramafic Index of Alteration (UMIA) and Index of Lateritization (IOL) are used to characterize the different stages of weathering of rocks and laterites. The calculated index values correspond to a less advanced stage of weathering of the Intex laterites compared with the Berong laterites. The Berong deposit is a Ni-Co laterite deposit in the Philippines, which is formed from the weathering of the serpentinized peridotite. The less extreme degree of weathering of the Intex laterites indicates less advanced leaching, and thereby the re-distribution of Ni, Si, and Mg from the limonite towards the saprolite horizon may have resulted in the poor precipitation of talc-like (kerolite-pimelite) and sepiolite-like (sepiolite-falcondoite) phases in the studied saprolite horizon. Nickel in the Intex deposit has undergone supergene enrichment similar to other humid tropical laterite deposits.

Characterization of manganese ores from Barru and Bone regencies of South Sulawesi has been conducted with the aim at clarification of their mineralogical and chemical composition for their potential uses as the raw materials for metallurgical industry. Mineralogical properties of the ores analyzed by means of optical microscopy and X-ray diffractometry (XRD) show that samples from Barru consist mainly of rhodochrosite (MnCO3) with less cryptomelane, groutite, bixbyite, and todorokite. Goethite, calcite and small amount of quartz present as impurities. Manganese ore samples from Bone are predominantly composed of pyrolusite (MnO2) with subordinate ramsdellite and hollandite. Barite, quartz, hematite and clay are present as gangue minerals. Chemical compositions determined by using XRF method revealed that Barru samples contain higher in MnO (average is 40.07 wt%) than the Bone samples (average is 34.36 wt%). Similarly, Fe2O3 and CaO are also higher in Barru than those of the Bone samples. In contrast, concentrations of SiO2 and total alkali (K2O + Na2O) are lower in the Barru samples. The average P2O5 content of samples in both areas is low (

The Khaldzan Burgedei peralkaline complex is one of the potential rare metal (Zr–Nb–REE) deposits in Mongolia. The complex consists mainly of quartz syenite and granite, and zircon is the most common accessory mineral in the rocks. Based on texture and mineral paragenesis, zircon is classified into three types. Type-I zircons in the quartz syenite and granite are generally isolated and euhedral to subhedral, 25–100 μm in size, enclosed by albite, K-feldspar, and quartz. Type-II zircons occur as subhedral to euhedral 20–150 μm grains, with quartz, and fluorite in the metasomatized zone in the quartz syenite as well as an upper part of the granite near the contact with the quartz syenite. These zircons contain porous core parts (Type-I) or remnants of corroded xenotime-(Y) and synchysite-(Ce). Type-III zircons are observed in the hydrothermally altered zone in quartz syenite and pegmatite. These zircons are anhedral, fine-grained, 10–30 μm in size, and occur in amphibole pseudomorphs which were replaced by quartz, fluorite, chlorite, and hematite. Laser Raman spectra show that Type-I and Type-II zircons contain high amounts of water. Among these, three types of zircons, Type-II zircons are most enriched in REE, Nb, and Th. The texture and composition of the three types of zircons indicate that Type-I, Type-II, and Type-III zircons are magmatic, metasomatic and late hydrothermal in origin, respectively, and they experienced remobilization and recrystallization during the transition from a magmatic to a hydrothermal system.

Mycotoxins are commonly present in cereal grains and are not completely destroyed during their cooking and processing. When mycotoxins contaminate staple foods, the risk for exposure becomes serious. In East Asia, including Japan, rice is consumed as a staple food, and with the increasingly Westernized lifestyle, the consumption of wheat has increased. The mycotoxins commonly associated with rice and wheat are total aflatoxin (AFL) and ochratoxin A (OTA), respectively. This study examined the retention of AFL and OTA during the cooking of rice and pasta. AFL was retained at 83%–89% the initial level after the cooking of steamed rice. In pasta noodles, more than 60% of the OTA was retained. These results show that AFL and OTA are relatively stable during the cooking process, suggesting that a major reduction in the exposure to these mycotoxins cannot be expected to occur by cooking rice and pasta. The estimated exposure assessment at the high consumer level (95th percentile) and the mycotoxin contamination level determined by taking into account these reductions in the present study should be useful for the establishment of practical regulations for mycotoxins in staple foods.

We have studied the color-center production in sapphire and yttria-stabilized zirconia (YSZ) single crystals by cathodo-luminescence (CL) spectroscopy for electron energies ranging between 400 and 1250 keV in a high-voltage electron microscope. Emission spectra were collected for in-beam conditions near room temperature and at 200 K. Comparison was made with CL spectra recorded for 3-keV-20-keV electrons in a scanning electron microscope. For high-energy electrons, CL spectra for sapphire revealed broad emission bands centered at photon energies about 3.0 eV and 3.8 eV that were, respectively, assigned to oxygen vacancies (F0 and F+ centers) induced by elastic collisions, on the basis of photoluminescence (PL) data. No such bands were recorded for 3-keV and 5-keV electrons. Two similar bands were also recorded for YSZ (with 9.5 and 18 mol. % yttria) at about 2.8 eV and 4.1 eV that can be, respectively, attributed to the native oxygen vacancies (F2+ centers) and F+ centers. The 4.1-eV band was not seen for 20-keV electrons: it was only produced for high electron energies by elastic collision processes. Instead, the small side band was also found at 2.85 eV for 20-keV electrons. PL excitation contour plots of virgin and irradiated YSZ were also recorded to support our discussion on point-defect identification. CL band intensities show a maximum versus electron energy, whereas point-defect concentrations should increase due to the increase of oxygen atom displacement cross section. The effect of electron energy on the different steps of the CL process is discussed to account for such a behavior. [ABSTRACT FROM AUTHOR]

In March 2011, Eastern Japan suffered serious damage of Tsunami caused by a massive earthquake. In 2012, Ministry of Land, Infrastructure and Transport published "Guideline of setting assumed areas of inundation by Tsunami" to establish the conditions of topography data used for simulation of Tsunami. In this guideline, the elevation data prepared by Geographical Survey Institute of Japan and 2m/5m/10m mesh data of NSDI are adopted for land area, while 500m mesh data of Hydrographic and Oceanographic Department of Japan Coast Guard and sea charts are adopted for water area. These data, however, do not have continuity between land area and water area. Therefore, in order to study the possibility of providing information for coastal disaster prevention, we have developed an efficient method to acquire continuous topography over land and water including tidal zone. Land area data are collected by Mobile Mapping System (MMS) and water area depth data are collected by interferometry echo sounder (C3D), and both data are simultaneously acquired on a same boat. Elaborate point cloud data of 1m or smaller are expected to be used for realistic simulation of Tsunami waves going upstream around shoreline. Tests were made in Tokyo Bay (in 2014) and Osaka Bay (in 2015). The purpose the test in Osaka Bay is to make coastal map for disaster prevention as a countermeasure for predicted Nankai massive earthquake. In addition to Tsunami simulation, the continuous data covering land and marine areas are expected to be used effectively for maintenance and repair of aged port and river facilities, maintenance and investigation of dykes, and ecosystem preservation. [ABSTRACT FROM AUTHOR]

Kyushu Island, Japan, is located at the junction of the Southwest Japan arc and the Ryukyu arc. There are two major late Cenozoic epithermal gold-silver provinces in Kyushu, which are termed the Northern and Southern provinces. The provinces are characterized by: 1) Pliocene volcanism dominated by calc-alkaline andesite, followed by Quaternary volcanism including extrusion of both calc-alkaline and tholeiitic magmas; 2) formation of extensional grabens; 3) Pliocene to Pleistocene mineralization, which was dominated by abundant low sulfidation (LS) epithermal deposits with a few high sulfidation (HS) examples. The two epithermal gold-silver provinces have evolved differently since about 5 Ma; the Northern province has exhibited diminished hydrothermal activity from the Pliocene to Pleistocene, whereas the Southern province has witnessed increased hydrothermal activity mainly in easterly and northerly directions. Changes of tectonic setting from the Pliocene to Pleistocene account for the variable trends in epithermal gold deposit formation. Westward oblique subduction of the Philippine Sea plate beneath the Southwest Japan arc caused development of the Hohi graben and arc-related volcanism at about 6 Ma. This was associated with widespread LS mineralization in and surrounding the Hohi graben, as is represented by the Bajo and Taio deposits. The subduction of the relatively buoyant Kyushu-Palau ridge during the early Pliocene strengthened the coupling between the slab and overriding Ryukyu arc, leading to polygenetic andesite volcanism with associated HS (Kasuga, Iwato, and Akeshi) and LS (Kushikino) mineral deposits forming in the Southern province. A change of the subduction direction of the Philippine Sea plate, from west to north-northwest in the early Pliocene, increased the orthogonal convergence rate between the Southwest Japan arc and the Philippine Sea plate, resulting in a decrease of volcanic and hydrothermal activity in the Hohi graben of the Northern province. The more northerly subduction of the Philippine Sea plate shifted the locus of the Kyushu-Palau ridge subduction northward, resulting in underplating of the older (85–60 Ma), negatively buoyant Amami basin oceanic slab in the Southern province, rather than continued subduction of the young (27–15 Ma), buoyant Shikoku basin slab. This replacement caused steepening of the slab angle and slab-rollback in the Southern province, which was associated with regional extension, an eastward shift of the Ryukyu volcanic front, and development of the Kagoshima and Shimabara grabens, as well as the Okinawa trough. Rhyolite and basalt volcanism, in addition to andesite volcanism, have occurred since 2 Ma in the area of the Ryukyu back arc; coincident LS mineralization at Hishikari and Ohkuchi was affiliated with the rhyolite volcanism. Another change of the subduction direction of the Philippine Sea plate to the northwest occurred at 2–1 Ma. The forearc sliver of the Southwest Japan arc shifted westward, in association with right-lateral strike-slip faulting along the Median tectonic line, due to the increase of the westward convergence rate. This shift resulted in shortening and cessation of graben development in the Hohi area, restricting the subsequent volcanism and related hydrothermal activity to the central part of the graben. [ABSTRACT FROM AUTHOR]

The Nueva Esperanza and Restauradora are two of the twenty-three veins described at Capillitas mine, an epithermal precious- and base-metal vein deposit located in northern Argentina. Capillitas is genetically linked to other mineralizations of the Farallón Negro Volcanic Complex, which hosts several deposits. These include two world-class (La Alumbrera and Agua Rica) and some smaller (e.g., Bajo El Durazno) porphyry deposits, and a few epithermal deposits (Farallón Negro, Alto de la Blenda, Cerro Atajo and Capillitas). The main hypogene minerals found at these two veins include pyrite, sphalerite, galena, chalcopyrite, tennantite-(Zn) and tennantite-(Fe). Accessory minerals comprise hübnerite, gold, silver, stannite, stannoidite and mawsonite, and also diverse indium- and tellurium-bearing minerals. Quartz is the main gangue mineral. Indium participates in the structure of sphalerite, tennantite-(Zn), ishiharaite and an indium-bearing mineral, still under study, the former being the most abundant of these phases. The chemical composition of sphalerite shows very low concentrations of Fe and a wide range in indium contents from below the detection limit (0.03 wt. %) to values close to 22 wt. %. Atomic proportions of In and Cu correlate positively at a ratio In : Cu = 1 : 1 atoms per formula unit. Cadmium reaches up to 0.68 wt. %. Other analyzed elements (Ge, As, Se, Ag, Sn, Te, Au, Pb and Bi) are systematically below their respective detection limits. Indium-bearing tennantite-(Zn) (up to 0.24 wt. % In) is rare and restricted to the area where ishiharaite appears. Ishiharaite and the unclassified indium-bearing mineral are extremely scarce and host up to 10 and 30 wt. % In, respectively. The zoning in sphalerite and the variable indium content of the different bands could be ascribed to significant fluctuation in the composition of the fluids (possibly pulses). They are evidenced by the presence of a high f Te2 mineral, like calaverite, and a low f Te2 phase, such as silver, within the same stage, with local periodic increments on In and Cu that could also be associated with recurring reactivation of fractures. [ABSTRACT FROM AUTHOR]