Analysis of vinylidene chloride and 1-chlorobutane in foods packaged with polyvinylidene chloride casing films by headspace gas chromatography/mass spectrometry (GC/MS)

A headspace gas chromatography/mass spectrometry method was developed for the simultaneous determination of vinylidene chloride and 1-chlorobutane in foods packaged with polyvinylidene chloride casing films. The solid foodstuff was homogenized with an equal mass of distilled water. The homogenate was incubated for 1 h at 90°C in a sealed headspace vial, and the headspace gas was then analysed by gas chromatography/mass spectrometry in selected ion-monitoring mode using a bonded porous polymer-coated capillary column. The recovery rates of vinylidene chloride and 1-chlorobutane in foodstuffs were 94.5-103.9 and 85.8-120.3%, respectively. Among 13 samples tested, vinylidene chloride was detected at 0.001-0.020 µg g^-1 in 11 foodstuffs, and 1-chlorobutane was detected at 0.004-0.040 µg g^-1 in all 13 foodstuffs. Furthermore, vinylidene chloride was detected at 0.04 µg g^-1 in one casing film, and 1-chlorobutane was detected in all casing films. The results indicate that these compounds migrated from the casing films into the foodstuffs.     

A differential photoconductive AND gate with Be-dopedlow-temperature-grown InGaAs-InAlAs MQW MSM-PD's

A novel photoconductive AND gate that overcomes the problems of: 1) the long tail of photoconductive switches and 2) signal leakage via switch capacitance (signal feedthrough) is proposed. We use Be-doped low-temperature (LT)-grown InGaAs-InAlAs MQW metal-semiconductor-metal photodetectors (MSM-PD's) to get a shorter turn-off time and propose a differential AND gate to cancel the signal feedthrough. A comparison between LT-grown MSM-PD's and those fabricated by ion implantation shows that the LT-grown ones are ultrafast with a full width at half maximum of 5.3 ps and are suitable for low-bias operation. It is experimentally confirmed that the differential AND gate completely cancels the signal feedthrough in the picosecond region. The differential AND gate: with the LT MSM-PD's achieves return-to-zero (RZ) 20 Gb/s AND operation     

Clinicopathologic features of submucosal carcinoma of the stomach

A retrospective study of 155 patients with submucosal gastric carcinoma compared the clinicopathologic features with mucosal and muscularis proprial gastric carcinoma. Fifty-seven percent of the patients presented with gastrointestinal symptoms, whereas 36.1% had been detected by mass screening. The incidence of curative resection, lymph node metastasis, and complications were 96.1, 20.6, and 14.8%, respectively. Two patients died of sepsis and pulmonary infarction 30 days post-operatively. Five patients died of recurrent gastric cancer 1-5 years postresection. The overall 5-year survival rate was 90.2%. Recurrence patterns, histologic type, lymph node metastasis, lymphatic and venous infiltration, and growth pattern were similar to those of muscularis proprial carcinoma rather than mucosal carcinoma. Therefore, curative gastrectomy with extended lymphadenectomy (D2) may be feasible for submucosal carcinoma of the stomach.     

Bottom-gate poly-Si thin film transistors using XeCl excimer laserannealing and ion doping techniques

High mobility bottom-gate poly-Si thin film transistors (TFTs) have been successfully fabricated on a hard glass substrate using XeCl excimer laser annealing and ion doping techniques. The authors used an a-Si:H film which is deposited by a plasma-enhanced chemical vapor deposition (PECVD) as a precursor film, and then they crystallized the a-Si film by XeCl excimer laser annealing. The maximum field effect mobility and grain size obtained were 200 cm²/V-s (n-channel), and 250 nm, respectively. The poly-Si TFTs showed excellent transfer characteristics, and an ON/OFF current ratio of over 10⁶ was obtained. Successful control of the threshold voltage within 4 V using an ion doping technique is also demonstrated     

Presenilin 1 mutations linked to familial Alzheimer's disease increase the intracellular levels of amyloid beta-protein 1-42 and its N-terminally truncated variant(s) which are generated at distinct sites

Mutations in the presenilin genes PS1 and PS2 cause the most common form of early-onset familial Alzheimer's disease. The influence of PS1 mutations on the generation of endogenous intracellular amyloid beta-protein (A beta) species was assessed using a highly sensitive immunoblotting technique with inducible mouse neuroblastoma (Neuro 2a) cell lines expressing the human wild-type (wt) or mutated PS1 (M146L or delta exon 10). The induction of mutated PS1 increased the intracellular levels of two distinct A beta species ending at residue 42 that were likely to be A beta1-42 and its N-terminally truncated variant(s) A beta x-42. The induction of mutated PS1 resulted in a higher level of intracellular A beta1-42 than of intracellular A beta x-42, whereas extracellular levels of A beta1-42 and A beta x-42 were increased proportionally. In addition, the intracellular generation of these A beta42 species in wt and mutated PS1-induced cells was completely blocked by brefeldin A, whereas it exhibited differential sensitivities to monensin: the increased accumulation of intracellular A beta x-42 versus inhibition of intracellular A beta1-42 generation. These data strongly suggest that A beta x-42 is generated in a proximal Golgi, whereas A beta1-42 is generated in a distal Golgi and/or a post-Golgi compartment. Thus, it appears that PS1 mutations enhance the degree of 42-specific gamma-secretase cleavage that occurs in the normal beta-amyloid precursor protein processing pathway (a) in the endoplasmic reticulum or the early Golgi apparatus prior to beta-secretase cleavage or (b) in the distinct sites where A beta x-42 and A beta1-42 are generated.     

Phylogenetic relationships among short wavelength-sensitive opsins of American chameleon (Anolis carolinensis) and other vertebrates

The vertebrate opsins have been classified into four major phylogenetic groups. One of them, a short wavelength-sensitive (SWS) opsin group, is further divided into two subgroups, SWS-I and SWS-II, having the wavelengths of maximal absorption of about 420 and 450 nm, respectively. Here we report the DNA sequences of the SWS-I and SWS-II genes from the lizard Anolis carolinensis. The shorter wavelengths of absorption by the two SWS subgroup opsins seem to be achieved by different sets of amino acid replacements in the transmembrane regions.     

Deimination of 70-kD nuclear protein during epidermal apoptotic events in vitro

Peptidylarginine deiminase (PAD) is the enzyme responsible for converting protein-bound arginine residues to citrulline. It has recently been shown that a number of epidermal proteins, including filaggrin, trichohyalin, and keratins, are deiminated by the action of PAD, suggesting a possible role for protein deimination during the final stages of epidermal differentiation. We report here a novel PAD substrate found during the course of identifying deiminated proteins in cultured rat epidermal keratinocytes. We found that a 70-kD protein localized to the periphery of the nucleus was preferentially deiminated after ionomycin treatment in the presence of 2 mM calcium and was associated with apoptotic events in these cells. Furthermore, we discovered that the deimination of nuclear protein could be induced by transfection of a PAD cDNA into rat epidermal keratinocytes. These data suggest that PAD may act on the 70-kD nuclear protein to induce disassembly of the nuclear lamina and promote apoptosis during terminal epidermal differentiation.     

Analysis of the drill hole orientation in anterior cruciate ligament reconstruction

In the reconstructive procedure of the anterior cruciate ligament (ACL), the relationship was investigated between the orientation of the drill holes from the isometric points and the deformity in the ligament graft. We first investigated, by numerical analysis, the optimal orientation of the drill holes for minimal deformation. Secondly, we experimentally by using eight fresh cadaveric knees, measured the relationship between the orientation of the drill holes and the bending angle in the grafts. The optimal orientation of the drill hole in the femur was found to be tilted 20 degrees laterally in the coronal plane and 23 degrees anteriorly in the sagittal plane. In the tibia, the drill hole should be directed 24 degrees medially and 50 degrees anteriorly from the isometric point. The numerically analysed bending angle corresponded well to the results from the experimental study. The deformation in the graft on the femoral side was larger than that on the tibial side. Therefore, the orientation of the femoral drill hole was concluded to be more important than the orientation of the tibial drill hole.     

Transcutaneous Blood Flow Measurement by Electromagnetic Induction

A new induction flowmeter which can measure the blood flow from the skin surface is discussed theoretically and experimentally. A pair of electrodes placed on the skin detect the EMF induced by the interaction of the blood flow and a magnetic field applied from outside the skin. The relation between the EMF and the flow rate, which is obtained theoretically, is also confirmed experimentally within the error of 10 percent.