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This article addresses aspects of earth-oven baking, as reported in ethnohistoric and ethnographic accounts from western North America and via a series of actualistic experiments. Ethnographic and ethnohistoric accounts attest to far more variability in oven morphologies, baking times, and food types than has been identified archaeologically. Toward mitigation of this data-discrepancy, we present methods and results of building and using nine earth ovens representative of those known ethnographically and expected to be represented in archaeological records. Our experiments demonstrate that earth-oven baking in a morphological variety of facilities is readily replicated by drawing from the ethnographic and ethnohistoric literature. Successful strategies are quickly learned through trial and error. With that comes an adequate understanding of how heat energy flows in various facilities along with recognition of critical roles of temperature, moisture availability, and cooking time, thereby providing...

Archaeologically oriented starch-granule and other plant-food microfossil research contribute to human subsistence studies primarily through analysis of residue adhering to plant processing tools. Little is known about whether or how plant-food microfossils may be present in remains of ancient earth ovens and other cooking facilities. Earth ovens with rock heating elements are found worldwide, especially in savannah and fuel-poor regions; they date to about 30,000 and 9,000 years old in the Old and New Worlds, respectively. Earth-oven baking is a cooking technology that effectively increases the availability of food in a given area by affording nutritional access to difficult-to-cook or toxic plant foods that would otherwise be indigestible. It effectively increases a landscape’s capacity to support population growth. Conventional-oven and lab-oven baking experiments assess the potential of ancient earth ovens to yield identifiable microfossils of underground storage organs (USOs) baked therein. During 15 min to 12 h of baking at 135–150 °C, identifiable and degraded USO microfossils accumulated as part of baking residue on cloth coverings, leafy packing materials, the inside of the containers, and on suspended microscope slides. Results of these taphonomic experiments indicate that an abundance of microfossils, including starch granules, phytoliths, raphides, and plant tissue, are emitted from USOs during the baking process. As hypothesized, these microfossils should be mobilized and dispersed in earth ovens per se during baking, primarily via liquid and vapor forms of water. Illuviation and other transformation processes are expected to redeposit baked, yet still identifiable, plant-food microfossils on heating-element rocks.

This study reports on evaluation of the optimum design of a blood outlet port structure for providing uniform flow by visualizing the blood flow in an extracapillary membrane oxygenator. We tested a cylindrical type extracapillary membrane oxygenator, HPO-20. The HPO-20 has a tangential blood outlet port and is thus referred to as "Tangential HPO-20." We engineered "Vertical HPO-20" with a vertical blood outlet port by modifying the Tangential HPO-20. To visualize the blood-side flow, a total of 120 insulated copper-wire electrodes were placed in the "Tangential" and the Vertical HPO-20s. The test solution flow was visualized by the dimensionless fluid arrival time reaching each electrode. The test solution flow in the Tangential HPO-20 was not uniform, particularly at the outside blood channel. The flow was more uniform in the Vertical HPO-20. The blood flow in an extracapillary membrane oxygenator with a vertical blood outlet port is well distributed so that it produces more uniform blood flow than that with a tangential outlet port because of the small stagnation and reduced channeling.

This study aimed to elucidate the microbial communities responsible for the decomposition of poly-(ϵ-caprolactone) (PCL), poly-(butylene succinate) (PBS), poly-(butylene succinate and adipate) (PBSA) and poly-lactide (PLA) in two soils using a culture-independent, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method with subsequent sequencing of the main DGGE bands. The PCL, PBS and PBSA films were considerably degraded within 50 days at 25°C under upland dark conditions in one soil, while the PLA film was not degraded at all after 120 days in the soil. In the other soil, with less soil organic matter content, only the PBSA films showed any discernible degradation in the 50-day incubation. Many fungal hyphae and hollows along fungal hyphae were observed on the surface of those PCL, PBS and PBSA films. The PCR-DGGE patterns of fungal DNA that were extracted from the degrading plastic films were similar between the soils, with a few different bands, irrespective of th...

Capability of the recycling of high strength and high fracture toughness yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) sintered body utilizing “low-temperature annealing degradation” phenomenon was investigated. Hydrothermal treatment was employed to induce the phase transformation from tetragonal to monoclinic zirconia and to disintegrate the Y-TZP sintered body. 3 mol% Y2O3–ZrO2 specimens sintered at 1,550 °C and more were disintegrated without leaving the original appearances when the treatment temperature was between 200 °C and 400 °C. The size of the disintegrated fragments of Y-TZP sintered body was much affected by hydrothermal treatment conditions. Only with hydrothermal treatment and simple ball milling, the sintered body was pulverized into the primary particle level. This technique is expected to apply to a sustainable recycling system for the zirconia ceramics, which restrains an energy consumption compared to crushing zirconia using mechanical procedures.

The recycling process for 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) sintered at 1450°–1550°C was examined by applying low-temperature degradation of zirconia ceramics under hydrothermal conditions. Hydrothermal treatment at a temperature from 200° to 240°C can lead to the spontaneous disintegration of 3Y-TZP sintered bodies into powdery particles. The hydrothermally obtained zirconia powder was found to consist of primary particles and aggregated particles. Detailed X-ray diffraction measurement revealed the formation of a cubic zirconia phase in the 3Y-TZP sintered bodies, which seemed to inhibit the disintegration of aggregated particles toward the primary particle level. The reclaimed 3Y-TZP powder was sintered again through a conventional powder processing route. The mechanical properties and microstructure of recycled 3Y-TZP sintered specimens were examined by comparison with those of the original 3Y-TZP sintered bodies. Dense recycled 3Y-TZP sintered at a higher temperature exhibited higher fracture toughness to some degree than the original 3Y-TZP.

Lead recovery from lead zirconate (PbZrO(3)) ceramics was investigated using a wet ball-mill treatment in H(2)SO(4) aqueous solution. Subsequently crystalline alpha-zirconium phosphate (alpha-Zr(HPO(4))(2).H(2)O) was synthesized using a hydrothermal technique in order for the resource recovery of zirconium in the wastewater after the wet ball-mill treatment. A wet ball-mill treatment in 4.5M H(2)SO(4) aqueous solution for 24h was capable of converting more than 99.9% of the Pb initially included in the PbZrO(3) to solid state PbSO(4) with a purity of 98%. On the other hand, the Zr in the PbZrO(3) was dissolved into the acidic solution during the treatment. The Pb and Zr metal elements coexisting in PbZrO(3) were successfully separated by the wet ball-mill technique. Then, resource recovery of zirconium in the wastewater was examined. Crystalline alpha-Zr(HPO(4))(2).H(2)O was synthesized by hydrothermal treatments in 3.1-12.5M H(3)PO(4) aqueous solutions at temperatures of 120-240 degrees C for a duration of 70h. The hydrothermally prepared powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and then they were also evaluated in terms of cation exchange capacity (CEC) measurement and thermogravimetric (TG) analysis.

Reductions of carboxylic acid derivatives by silanes in the presence of rhodium complexes were studied. Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by [RhCl(cod)]2/4PPh3 ...

The object of this study was to develop a highly porous scaffold to be used in regeneration of blood vessels, nerves, and other hollow tissues with small openings. Using the phase-inversion method and a mixture of water and methanol as a coagulating agent, we prepared highly porous flat membranes from poly(L: -lactic acid) (PLLA) with numerous pores both on the surface and in the interior of the membranes. Chinese hamster ovary (CHO) cells were cultured on the membranes to evaluate initial cell adhesion, cell proliferation, and cell morphology. Adhesion of CHO cells to PLLA was poor: the cells adhered at approximately half the rate observed with a tissue culture polystyrene dish (TCPS). In contrast, adhesion of cells to PLLA treated with a low-temperature oxygen plasma was good; the adhesion rate was the same as that on TCPS. The rate of cell proliferation on the treated membranes was no different from that on the nontreated membranes, but cell morphologies were quite different. The cells on the nontreated membranes were small and round and proliferated separately from one another. In contrast, the cells on the plasma-treated membranes proliferated in close contact with other cells, spreading out extensively in sheet-like formations. Since the plasma treatment not only accelerated cell adhesion but also enabled cells to proliferate in the form of sheets resembling biological tissue, we believe that oxygen-plasma treatment is extremely effective for modifying surfaces of materials used for tissue regeneration.

Thrombosis and bleeding are major complications in cases of prolonged extracorporeal lung assist (ECLA) with an artificial-membrane lung. Antithrombogenic treatment of the artificial-membrane oxygenator and circuits is indispensable for safe ECLA. The efficacy of a new heparin-coated membrane lung with minimal systemic heparinization was evaluated for 7 days and compared with a nonheparin-coated membrane lung in goats. The animals were randomly assigned to either the heparin-coated membrane group (HM group, n = 5) or nonheparin-coated membrane group (NHM group, n = 5). Activated coagulation time (ACT) during ECLA was controlled to below 150 s in the HM group, and to near 200 s in the NHM group. All goats in the HM group were sustained on ECLA for 7 days, but two goats in the NHM group died on the 4th and 6th days, respectively. The mean systemic administration rate of heparin during ECLA was 22.4 +/- 4.4 U/kg/h in the HM group and 39.0 +/- 10.0 U/kg/h in the NHM group. There was a significant difference between the two groups (P < 0.05). The oxygen transfer rate, the Pco(2) difference, the perfusion resistance, and platelet counts showed no significant changes. There was no plasma leakage from the artificial lung. Although several clots were observed in the stagnant areas of the artificial lung, they did not lead to deterioration of the function of the artificial lung. The excellent antithrombogenicity, gas exchange ability, and durability of this new artificial lung with circuits might contribute to successful prolonged ECLA with minimal systemic heparinization.

The recovery of lead from PLZT ((Pb 0.9 La 0.1 ) (Zr 0.52 Ti 0.48 )O 3 ) ceramics was investigated by the wet ball-mill method using 1.4-11.3 M H 2 SO 4 aqueous solutions. The wet ball-mill treatment was performed in a pot mill apparatus at room temperature for 0-72 h with a rotational speed fixed at 300 rpm. It was found by X-ray diffraction (XRD) analysis that the treatment time required for completely converting from crystalline PLZT to PbSO 4 nano-particles could be shortened with increasing H 2 SO 4 concentration. According to inductively-coupled-plasma atomic-emission (ICP-AES) analysis of the components dissolved into the solution, the amount of dissolved zirconium and titanium ions increased with increasing treatment time. The dissolution of both components was closely related to the disintegration behavior of crystal structure of PLZT ceramics. The amount of dissolved lead ion was about 0.1% of the lead included in the non-treated PLZT under the whole experimental conditions, while that of lanthanum ion was below 60%. The amount of lanthanum ion dissolved into the solution was dependent on the concentration of H 2 SO 4 aqueous solution used for treatments. These results indicated that the wet ball-mill method gave a yield of PbSO 4 as high as 99%, and the purity of the collected PbSO4 from PLZT ceramics was about 91-95%.

The possibility of preferential recovery of lead from lead zirconate titanate (PZT) ceramics by wet ball milling with aqueous H 2 SO 4 solution was investigated. The wet ball milling was performed using a pot mill apparatus in air for 0-96 h at room temperature with the rotational speed fixed at 300 rpm. Untreated PZT was dipped in aqueous H 2 SO 4 solution for comparison with the wet-ball-milled specimen. The diffraction lines of the PZT crystallites disappeared completely from the XRD results, and only the diffraction lines of PbSO 4 were confirmed by the wet ball milling for more than 48 h. For all the dipped specimens, the diffraction lines of PZT were identified even when the specimens were treated in 4.5 mol/dm 3 H 2 SO 4 solution for 96 h. According to ICP analysis of the dissolved components into the H 2 SO 4 filtrate, the amounts of zirconium and titanium dissolved in the solution were found to increase with increasing treatment time, and the leaching behavior of both ions conformed closely to the collapsing behavior of the PZT crystal structure. As for lead ion in the solution, the dissolution amount was below 0.1% compared with the initial lead content in PZT ceramics under all the ball milling conditions. These results indicated that more than 99.9 mass% of lead in PZT can be recovered as PbSO 4 by wet ball milling for more than 48 h. The purity of the recovered PbSO 4 calculated from the ICP results was approximately 98 mass%.

Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by a Rh complex at room temperature. For example, ethyl decanoate and ethyl phenylacetate were converted to decanol and 2-phenylethanol by [ RhCl(cod) ] 2 4PPh 3 for 72 hours in 98 and 92% yields, respectively. Wilkinson's catalyst is also usable, and the reduction of ethyl decanoate finished in 6 hours at room temperature. The bromo-substitutent on ethyl 7-bromoheptanoate remained intact through this reduction.

A new purification method for rat liver glucokinase was developed. Glucokinase was purified to homogeneity in a yield of 70% in 5 days. The procedure consists of DEAE-cellulose ion-exchange chromatography, QAE-Toyopearl ion-exchange chromatography, glucosamine-Sepharose affinity chromatography, and HiLoad Superdex 200 gel filtration. Purified glucokinase had a specific activity of 200 units/mg protein and was highly stable in the presence of 100 mM glucose, 300 mM KCl, and 20% glycerol. We found that some of the methionine residues of glucokinase were oxidized to methionine sulfoxide residues during dialysis in the presence of glucose. It would appear that this oxidation is caused by formation of hydroxyl radicals in the presence of glucose and contaminating transition metal(s).

By an immunohistochemical technique, we examined changes in the subcellular distribution of rat liver glucokinase in response to external stimuli. Glucokinase immunoreactivity was found predominantly in the nucleus of hepatocytes. In situ perfusion of the liver with 20 mM glucose for 10 min caused a marked decrease in nuclear immunoreactivity and an increase in cytoplasmic immunoreactivity. Insulin (10 nmol/l) potentiated this glucose effect. However, no change took place when 5 mM glucose was perfused. These results indicate that glucokinase is translocated from the nucleus to the cytoplasm in response to a high concentration of glucose.

Carboxylic esters were reduced to alcohols by diphenylsilane catalyzed by a Rh complex at room temperature. For example, ethyl decanoate and ethyl phenylacetate were converted to decanol and 2-phenylethanol by [ RhCl(cod) ] 2 4PPh 3 for 72 hours in 98 and 92% yields, respectively. Wilkinson's catalyst is also usable, and the reduction of ethyl decanoate finished in 6 hours at room temperature. The bromo-substitutent on ethyl 7-bromoheptanoate remained intact through this reduction.

A novel cobalt recovering process from a cobalt-based cathode electrode in a lithium secondary cell was developed using a hydrothermal treatment combined with a pyrometallurgical technique. A cobalt-based cathode electrode was prepared by casting the mixture of LiCoO2, poly(vinylidene fluoride) and conductive carbon black onto an Al foil, and this model electrode was used as a test sample. A hydrothermal treatment of the cathode sample was carried out using pure water as a solvent in the temperature range of 423–473 K for the duration of 0–40 h. The hydrothermal treatment at 473 K for more than 15 h led the cathode sample to the disintegration into powdery particles. By the hydrothermal treatment under the optimum condition at 473 K for 20 h, more than 99.9 mass% of Co and 98 mass% of Al in the cathode sample was reclaimed as a form of spinel type Co(CoxAl2-x)O4 (0

Subcellular and zonal distribution of glucokinase in rat liver during postnatal development was examined immunohistochemically. Before day 11 after birth, only some hepatocytes were immunostained, and a positive immunostaining was found in the cytoplasm but not in the nucleus. No zonal distribution of glucokinase was observed in livers of such pups. From day 15, at which time a dietary change from milk to laboratory chow begins to take place, glucokinase immunoreactivity increased; this increase was associated with increases in glucokinase activity and in glucokinase protein, and also the immunostaining was observed mainly in the nuclei. At day 21, the glucokinase immunoreactivity was found almost exclusively in the perivenous zone. At day 30, an intense immunostaining was seen both in the perivenous zone and in the periportal zone, being slightly predominant in the former. The present results indicate that dramatic changes in the distribution of glucokinase in developing rat liver may be related to dietary change.

The distribution of glucokinase in rat liver under both normal feeding and fasting-refeeding conditions was investigated immunohistochemically. Under normal feeding conditions, glucokinase immunoreactivity was observed in both nuclei and cytoplasm of parenchymal cells. The nuclei were stained intensely and evenly, whereas the cytoplasm showed weak immunoreactivity of different degrees of staining intensity depending on the location of the cells. The cytoplasm of perivenous hepatocytes was stained more intensely, though not so much more, than that of periportal hepatocytes. The cytoplasm of hepatocytes surrounding the terminal hepatic venule (THV), of hepatocytes surrounding the portal triad, and of some other hepatocytes showed a stronger immunoreactivity than that of residual hepatocytes. The nuclear immunoreactivity in hepatocytes surrounding the portal triad and in some other hepatocytes was weak or absent, and positive immunoreactivity was detected at the plasma membrane of some of these cells. After 72 h of fasting, glucokinase immunoreactivity was markedly decreased in all hepatocytes. After the start of refeeding, the cytoplasmic immunoreactivity began to increase first in the parenchymal cells surrounding the THV and extended to those in the intermediate zone followed by those in the periportal zone. In contrast, the increase in nuclear immunoreactivity started in hepatocytes situated in the intermediate zone adjacent to the perivenous zone and then extended to those in the perivenous zone followed by those in the periportal zone. Hepatocytes surrounding either THV or portal triad showed a distinctive change in immunoreactivity during the refeeding period. After 10 h of refeeding, strong immunoreactivity was observed in both the cytoplasm and the nuclei of all hepatocytes, and appreciable glucokinase immunoreactivity was detected at the plasma membrane of some hepatocytes. These findings are discussed from the standpoint of a functional role of glucokinase in hepatic glucose metabolism.

The reaction of dimethyl sulfoxide–trifluoroacetic anhydride complex with anilines, phenols, and thiophenols was studied, and the following results were obtained. (1) The yields of a methylthiomethylated product were improved with anilines. The reaction proceeded without significant amount of tar, the unreacted anilines being easily recovered. (2) Selective ortho-methylthiomethylation took place with phenols in good yields at lower temperature, para-methylthiomethylation occurring at higher temperature. (3) Methylthiomethylation took place with thiophenols on a sulfur atom of thiophenol at room temperature in a simple process.

Fungal infections of the paranasal sinuses were considered to be rare in occurrence. However, in recent years reports of such infection seem to have increased. In this report we presented two cases of aspergillosis of the maxillary sinus.Case 1: A 46-year-old woman was referred to our university clinic with the chief complaint of pain in the right maxilla. Sinus x-rays showed opacification of the right maxillary sinus with calcification which resembled a foreign body. Clinical diagnosis of the right maxillary sinusitis was made and the Caldwell-Luc operation was performed revealing a sinus existed with brown caseous materials. Postoperative histopathological examination of this material revealed the presence of aspergillus.Case 2: The patient was a 42-year-old woman. After the extraction of a maxillary molar tooth, nasal discharge continued. She was referred to our university clinic by her dentist. Sinus x-rays showed opacification of the left maxillary sinus with calcification. Clinical diagnosis of the left odontogenic maxillary sinusitis was made. Similarly to case 1, the patient underwent the Caldwell-Luc operation which revealed brown caseous materials, and postoperative microscopic examination revealed septate fungal organisms consistent with aspergillus.

The reaction of dimethyl sulfoxide–trifluoroacetic anhydride complex with anilines, phenols, and thiophenols was studied, and the following results were obtained. (1) The yields of a methylthiomethylated product were improved with anilines. The reaction proceeded without significant amount of tar, the unreacted anilines being easily recovered. (2) Selective ortho-methylthiomethylation took place with phenols in good yields at lower temperature, para-methylthiomethylation occurring at higher temperature. (3) Methylthiomethylation took place with thiophenols on a sulfur atom of thiophenol at room temperature in a simple process.