Pyrrolizidine Alkaloids Mediate Host-Plant Recognition by Ovipositing Females of an Old World Danaid Butterfly, Idea leuconoe

A giant danaid butterfly, Idea leuconoe, specializes on apocynaceous plants such as Parsonsia laevigata, which has been reported to contain pyrrolizidine alkaloids. Females of I. leuconoe deposited eggs in response to methanolic extract of P. laevigata, and subsequent bioassay-guided fractionation of the extract revealed that phytochemicals crucial for host recognition by ovipositing females are Parsonsia-specific macrocyclic pyrrolizidine alkaloids including parsonsianine, parsonsianidine, and 17-methylparsonsianidine. Parsonine, another P. laevigata pyrrolizidine component with a keto-dihydropyrrolizine moiety that is closely related in structure to male pheromones of the butterfly, and several nonhost pyrrolizidine alkaloids were entirely inactive. We interpret these data as strong evidence for an ancestral association through herbivory between danaid butterflies and pyrrolizidine alkaloids.     

Differences in knowledge production between disciplines based on analysis of paper styles and citation patterns

To identify the differences in the knowledge production between disciplines, we analyzed the relation between the average paper length and impact factor of 100 journals from 5 disciplines. We found negative correlation between the average length and the impact factor in the natural sciences, but not in the social sciences. We also analyzed the structures of paper and the citation patterns. These analyses are expanded to the comparison between Mode 1 and Mode 2. All results showed the natural sciences articles could emphasize the differences from previous studies and be diffused effectively by the short standardized style of paper. This research is partly funded by International Program in Special Coordinating Funds for Promoting S&T from Science and Technology Agency of Japan.     

SPRAY DRYING CHARACTERISTICS BY A CENTRIFUGAL PRESSURE NOZZLE WITH LARGE ORIFICE DIAMETER

A study was made of a centrifugal pressure nozzle with large orifice diameter (8-10 nun) for producing dry milk in capacity of 2-3 tons per hour to develop some performance data on spray distribution, drop size distribution, and capacity with changing spray drying conditions such as nozzle pressure, orifice diameter and spray angle.

Experimental results were shown as follows.

(1) A centrifugal pressure nozzle of large capacity such as 5,000- 5,500 l/hr at 150 kg/cm2 spray pressure and 110°s ray angle was designed by using the nozzle parameter Si/dedi√di/di.

(2) Atomization characteristics were greatly affected by the ratio of orifice diameter (de) to the length (L) of the nozzle core. The smaller the ratio, around 0.125, the better are the atomizing effects.

(3) The large orifice can be used at least 3,000 hr in the spray drying operation for milk without any wear in the orifice although it is only made of stainless steel.

As a result, a spray dryer of large capacity for dry milk has been operated by a mono nozzle with a large orifice without any trouble for a long time     

Hybridized synergy effect among TiO2, Pt and graphite silica on photocatalytic hydrogen production from water–methanol solution

The photocatalytic production of hydrogen gas from aqueous methanol solution was performed using powdered mixtures of graphite silica (GS) and platinized TiO₂ (Pt/TiO₂) or those of GS, Pt and TiO₂. The addition of GS to Pt/TiO₂ resulted in the decrease of the amount of H₂ gas, whereas the addition of GS to mixtures of TiO₂ and Pt led to the incremental production of H₂ gas. This effect is attributed to the aggregation of GS, TiO₂ and Pt in suspension. The new additional electron transfer process of TiO₂ → Pt → GS caused the increment of the amount of hydrogen gas.     

Effect of impact energy on the impact-wear properties of low carbon high manganese alloy steels in corrosive conditions

The impact-wear properties of low carbon high manganese alloy steel were tested under three different impact energies (0.7 J, 1.2 J and 1.7 J) using a modified MLD-10 wear tester. SEM inspection of the wear surface and subsurface optical metallographic analysis reveal the impact wear mechanism. Under corrosive conditions we observe a shift from single micro-cutting to impact-flaking, after the appearance of vertical section micro-cracks, while at higher impact energies fatigue corrosion and abrasion are observed.     

An analysis of a clear-view angelfish bubble-domain shift register

A clear-view display and printing device is proposed utilizing a new bubble-domain shift register which has triangular patterns etched into the surface of a magnetic crystal. The geometrical and materials requirements for the clear-view shift register are analyzed. The etched-out triangular pattern is shown to provide the unidirectionality of bubble motion under an oscillating bias field just as the triangular Permalloy overlay does. An etched depth of one-tenth of the plate thickness and an etched gradient of about unity are shown to be sufficient for the expected shift-register operation.     

Understanding consumer heterogeneity: A business intelligence application of neural networks

This paper describes a business intelligence application of neural networks in analyzing consumer heterogeneity in the context of eating-out behavior in Taiwan. We apply a neural network rule extraction algorithm which automatically groups the consumers into identifiable segments according to their socio-demographic information. Within each of these segments, the consumers are distinguished between those who eat-out frequently from those who do not based on their psychological traits and eat-out considerations. The data set for this study has been collected through a survey of 800 Taiwanese consumers. Demographic information such as gender, age and income were recorded. In addition, information about their psychological traits and eating-out considerations that might influence the frequency of eating-out were obtained. The results of our data analysis show that the neural network rule extraction algorithm is able to find distinct consumer segments and predict the consumers within each segment with good accuracy.     

Review of pulmonary toxicity of indium compounds to animals and humans

Due to the increased production of ITO, the potential health hazards arising from occupational exposure to this material have attracted much attention. This review consists of three parts: 1) toxic effects of indium compounds on animals, 2) toxic effects of indium compounds on humans, and 3) recommendations for preventing exposure to indium compounds in the workplace.Available data have indicated that insoluble form of indium compounds, such as ITO, indium arsenide (InAs) and indium phosphide (InP), can be toxic to animals. Furthermore, InP has demonstrated clear evidence of carcinogenic potential in long-term inhalation studies using experimental animals. As for the dangers to humans, some data are available concerning adverse health effects to workers who have been exposed to indium-containing particles. The Japan Society for Occupational Health recommended the value of 3 μg/L of indium in serum as the occupational exposure limit based on biological monitoring to preventing adverse health effects in workers resulting from occupational exposure to indium compounds. Accordingly, it is essential that much greater attention is focused on human exposure to indium compounds, and precautions against possible exposure to indium compounds are most important with regard to health management among indium-handling workers.     

Molecular cloning, cDNA sequence analysis, and chromosomal localization of mouse Pkd2

The gene responsible for the second form of autosomal dominant polycystic kidney disease, PKD2, has recently been identified. We now describe the cloning, genomic localization, cDNA sequence, and expression analysis of its murine homologue, Pkd2. The cloned cDNA sequence is 5134 bp long and is predicted to encode a 966-amino-acid integral membrane protein with six membrane-spanning domains and intracellular NH2 and COOH termini. Pkd2 is highly conserved with 91% identity and 98% similarity to polycystin-2 at the amino acid level. Pkd2 mRNA is widely expressed in mouse tissues. Pkd2 maps to mouse Chromosome 5 and is excluded as a candidate gene for previously mapped mouse mutations resulting in a polycystic kidney phenotype.