In vitro assessment of the cytotoxicity of anti-allergic eye drops using 5 cultured corneal and conjunctival cell lines

The aim of this study was to evaluate the cytotoxicity of anti-allergic eye drops for human corneal endothelial cells (HCEC) and commercially available ocular surface cells. A primary HCEC culture was derived from human eye bank specimens. SIRC (rabbit corneal epithelium), BCE C/D-1b (bovine corneal epithelial cells), RC-1 (rabbit corneal epithelium), and Chang (human conjunctival cells) were obtained commercially. The WST-1 assay was used to measure HCEC viability, and the viability of other cells was measured using the MTT assay. Cells were treated with 7 commercially available anti-allergic eye drops for 48 h and cell viability was measured and calculated as a percentage of control. The degree of toxicity for each eye-drop solution was based on the cell viability score (CVS). HCECs treated with a 1000-fold dilution of the eye-drop solution had a viability score of 67% for Rizaben and ≥80% for the other solutions with Zepelin being the least toxic. Cell viability in response to eye-drop solutions preserved with benzalkonium chloride (BAK) was dependent on the concentration of the drug solution and exposure time. Treatment of ocular surface cells with a 20-fold dilution of the eye-drop solution resulted in the following order of cell viability as determined by their CVS: Zepelin > Ketas = Zaditen ≥ Tramelas PF = Patanol ≥ Rizaben ≥ Livostin. This order was similar to that observed for HCECs, and cell viability was found to be concentration-dependent. Based on the penetration of the drug into eye tissues, HCECs are only likely to be pharmaceutically damaging in rare cases. Epithelial cell viability depends primarily on the concentration of BAK rather than on the action of the active component in the eye-drop solution. CVS values were useful for comparison of toxicity.     

Performance improvement and decolourization in the high-solid thermophilic anaerobic digestion of thermally pretreated sewage sludge

This laboratory-scale study attempted performance improvement and decolourization in the high-solid thermophilic anaerobic digestion of thermally pretreated sewage sludge, as it tends to be disturbed by ammonia inhibition and colour generation. Sewage sludge was adjusted to 7%–8% total solids (TS), and pretreated at 150°C for 1 h. The digesters were operated at 55°C and 20 days hydraulic retention time. An addition of powdered activated carbon (approximately 2% of the feed TS) significantly contributed to the removal of propionate and reduced the colour in digested sludge by about 27%. Microbial analysis detected less abundance of bacterial Synergistia and archaeal Methanosarcina and implied more hydrogenotrophic methanogenesis with the activated carbon addition. Conditioning with ferric chloride for dewatering digested sludge mitigated the colour of dewatered liquor by about 67%. Therefore, these methods were demonstrated to be effective and partly overcome the above-mentioned problems.     

Improvement of high temperature stability of Pd coating on Ta by HfN intermediate layer

Hafnium nitride (HfN) was chosen as a material for non-porous intermediate layer to improve the high temperature stability of Pd–Ta composite membranes for hydrogen separation. A layer of dense HfN (70 nm) was prepared between Ta substrate and thin Pd film (300 nm), and the high temperature stability of Pd coating was examined by hydrogen absorption experiments at 573 K after the heat treatments at 873 and 973 K. The HfN layer showed obvious hydrogen permeability, though the permeation rate in HfN appeared to be smaller than that in Pd and Ta. In addition, the degradation in coating effects of Pd at elevated temperatures was substantially retarded by HfN layer. Such improved stability was ascribed to retardation of open porosity development in Pd films and interdiffusion between Pd and Ta. It was concluded that HfN is a potential candidate material for intermediate layer to improve high temperature stability of Pd-group 5 metal composite hydrogen separation membranes.     

A CMOS 510 K-transistor single-chip token-ring LAN controller (TRC)compatible with IEEE802.5 MAC protocol

The token-ring controller (TRC) consists of five functional blocks. they are a dedicated 16-b microprocessor which includes 11 K-word×20-b protocol firmware ROM, finite-state machines for real-time handling of frames, an 896-word×16-b dual-port RAM for frame buffer FIFOs and working memory (FIFO/RAM), a host processor bus interface, and a three-channel DMA controller which can follow list structure frame buffers. The TRC interprets and executes 16 types of commands and handles 23 types of media access control (MAC) frames. It can continuously receive more than 90% of incoming packets with 64-byte information length at 40 Mbit/s network speed. It is fabricated with double-metal-layer 1.2-μm CMOS technology and integrates 510 K MOSFETs in a 14.49-mm×14.62-mm chip area. The maximum power consumption is 0.945 W at 8-MHz operating frequency and 5-V±5% power supply low-power systems but also for high-performance applications     

Trichohyalin expression in skin tumors: retrieval of trichohyalin antigenicity in tissues by microwave irradiation

PURPOSE: To establish the influence of age, sex and the presence of coronary heart disease on heart rate variability. METHODS: The heart rate variability was studied in the time and frequency domain in 77 normal (group I) and 30 coronary heart disease patients (group II). The ECG was recorded during 300 seconds with the patients breathing at their spontaneous rate and at a rate between 10 and 15/ minutes (0.16 to 0.25 Hz). RESULTS: Both time and frequency domain variables were lower in group II than in group I. Energy content in spectral bands decreased with increasing age. No change was observed in relation to the patient's gender. During controlled breathing we found that in both groups the energy concentrated in the range of 0.17 to 0.25 Hz but it only increased in group I. CONCLUSION: Heart rate variability is an important tool for studying the influence of the autonomic system on heart rate modulation. These influences decrease with age and with the presence of coronary heart disease. The controlled breathing maneuver enabled us to precisely separate normal from coronary heart disease patients.     

An investigation of factors controlling part growth and surface finish of form tools in the automatic screw machine test

In order to investigate factors controlling part growth and surface finish in the automatic screw machine test, a set of eight separate experiments was carried out. It was observed that flank wear is the major factor in controlling rough-form part growth, but does not account for all of it. Other possible factors were reviewed. The elastic deflection of the workpiece estimated from the increase of the taper of rough-formed part with machine time appears to account for most of the difference between the observed part growth and the estimated values from flank wear. BUE overhang and thermal expansion of the workpiece could also contribute to rough-form part growth. The contribution of BUE overhang could be either positive or negative depending on how overhang size changes with machine time. Thermal expansion of the workpiece would give rise to negative part growth. Interestingly, during the initial 30 min of machining, negative part growth for rough-form tool and rapid positive part growth for finish-form tool were observed. Thermal expansion for the rough-form tool and the change in the size of BUE overhang for both tools are believed to be at least partially responsible for these effects. A procedure to start measuring part growth after approximately 30 minutes of machining is thus recommended. For finish-formed surface finish in this investigation, uneven BUE is believed to be the dominant factor in determining surface roughness.     

Enumeration of viable Escherichia coli by real-time PCR with propidium monoazide

A photo-inducible DNA-binding dye, propidium monoazide (PMA), was used to distinguish viable and dead Escherichia coli cells. Microscopic observations using a combination of the dyes 4',6-diamidino-2-phenylindole and PMA indicated that PMA stained only dead cells, with membrane damage, red. Mixtures of viable and heat-treated E. coli cells were subjected to real-time polymerase chain reaction (PCR) with PMA treatment. Viable cell counts were linearly related to real-time PCR threshold cycle values for PMA-treated cells in the mixtures of viable and heat-treated cells, as long as the ratio of dead cells to viable cells was no greater than 10. In the wastewater treatment plants, total, viable and culturable E. coli were enumerated by real-time PCR, real-time PCR coupled with PMA treatment and the most probable number method using EC-MUG medium, respectively. The concentrations of viable E. coli in the wastewater treatment plants were much higher than those of culturable cells. In addition, viable cells were even more chlorine resistant than culturable ones.     

Organizing the Web's Information Explosion to Discover Unknown Unknowns

This paper introduces the TORISHIKI-KAI project, which aims to construct a million-word-scale semantic network from the Web using state of the art knowledge acquisition methods. The resulting network can be browsed as a Web search directory, and we show that the directory is useful for finding “unknown unknowns” — in the infamous words of D.H. Rumsfeld: things “we don't know we don't know.” Because typically we have no way to look for information we don't even know is missing, a crucial characteristic of unknown unknowns is that they are very difficult to discover through keyword-based Web search. Some examples of the unknown unknowns we have found include unexpected troubles associated with commercial products, surprising new combinations of ingredients in new recipes, unexpected tools or methods for commiting suicide, and so on. We expect such information to be useful for risk management, innovation support, and the detection of harmful information on the Web.