A 3.3-V single power supply 16-Mb nonvolatile virtual DRAM using aNAND flash memory technology

A 3.3-V 16-Mb nonvolatile memory having operation virtually identical to DRAM with package pin compatibility has been developed. Read and write operations are fully DRAM compatible except for a longer RAS precharge time after write. Fast random access time of 63 ns with the NAND flash memory cell is achieved by using a hierarchical row decoder scheme and a unique folded bit-line architecture which also allows bit-by-bit program verify and inhibit operation. Fast page mode with a column address access time of 21 ns is achieved by sensing and latching 4 k cells simultaneously. To allow byte alterability, nonvolatile restore operation with self-contained erase is developed. Self-contained erase is word-line based, and increased cell disturb due to the word-line based erase is relaxed by adding a boosted bit-line scheme to a conventional self-boosting technique. The device is fabricated in a 0.5-μm triple-well, p-substrate CMOS process using two-metal and three-poly interconnect layers. A resulting die size is 86.6 mm², and the effective cell size including the overhead of string select transistors is 2.0 μm²     

Dichotomous behavior of polymer melts in isothermal melt spinning

Isothermal melt spinning experiments have been conducted using two polyethylene melts of low density (LDPE) and high density (HDPE) to produce steady state spinline profiles. The data revealed the threadline extensional viscosity exhibiting a contrasting picture : extension thickening behavior for LDPE and extension thinning one for HDPE. A White-Metzner model having a strain rate-dependent relaxation time was then found to be able to simulate this dichotomy in melt spinning fairly well: the fluids whose relaxation times have smaller strain rate-dependence can fit LDPE data with extension thickening extensional viscosity whereas the fluids whose relaxation times have larger strain rate-dependence can fit HDPE data with extension thinning extensional viscosity. This dichotomous nature of viscoelastic fluids is also believed to be able to explain other similar contrasting phenomena exhibited by polymer melts, such as vortex/no vortex in entry flows, cohesive/ductile fracture modes in extension, and more/less stable draw resonance than Newtonian fluids.     

Integrated modelling under uncertainty in watershed-level assessment and management.

Uncertainty in water quality model predictions is inevitably high due to natural stochasticity, model uncertainty, and parameter uncertainty. An integrated modelling system (modified-BASINS) under uncertainty is described and demonstrated for use in receiving-water quality prediction and watershed management. A Monte Carlo simulation was used to investigate the effect of various uncertainty types on output prediction. Without pollution control measures in the watershed, the concentrations of total nitrogen (T-N) and total phosphorus (T-P) in the Hwaong Reservoir, considering three uncertainty types, would be less than about 4.4 and 0.23 mg L(-1), respectively, in 2012, with 90% confidence. The effects of two watershed management practices, wastewater treatment plants (WWTP) and constructed wetlands (WETLAND), were evaluated. The combined scenario (WWTP + WETLAND) was the most effective at improving reservoir water quality, bringing concentrations of T-N and T-P in the Hwaong Reservoir to less than 3.4 and 0.14 mg L(-1), 24 and 41% improvements, respectively, with 90% confidence. Overall, the Monte Carlo simulation in the integrated modelling system was practical for estimating uncertainty and reliable in water quality prediction. The approach described here may allow decisions to be made based on the probability and level of risk, and its application is recommended.     

Central GABAA and GABAB receptor modulation of basal and stress-induced plasma interleukin-6 levels in mice

The development of control strategies for loiasis is of crucial importance in endemic areas and depends heavily on the accurate identification of occult-infected individuals. A polymerase chain reaction (PCR) and nested polymerase chain reaction (nested PCR) were developed and based on sequences of the repeat 3 region (15r3) of the gene encoding a Loa loa 15-kD protein. The assays was performed on 20 blood samples from occult-infected subjects and 30 from field-collected amicrofilaremic individuals. The size of the initial PCR product was 396 basepairs (bp). When this initial amplification using primers 15r3(1) and 15r3(2) was carried out for 30 cycles, the PCR products from three of the 20 occult-infected and five of the 30 amicrofilaremic individuals were visualized after electrophoresis by staining the gel with ethidium bromide. Subsequent Southern blotting and hybridization with the specific probe revealed hybridization in 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples but only after two days of exposure of the blot to the x-ray film. When the nested PCR was carried out (product size = 366 bp, primers 15r3(3) and 15r3(4)), 19 of 20 occult-infected and 23 of 30 amicrofilaremic samples that were positive by Southern hybridization of the initial PCR products were strongly positive by staining with ethidium bromide. Qualitative Southern blotting of the nested PCR products using the same probe previously described confirmed the ethidium bromide staining results after a very short exposure time of 4 hr. These results demonstrate that the nested PCR amplification product is specific and that its sensitivity in detecting occult loiasis is 95%. This approach has significant promise for the screening of large human populations for active loiasis without the requirement for blotting and hybridization of the PCR products.     

Perioperative specific management of blood volume loss in craniosynostosis surgery

Accurate assessment and replacement of blood loss and fluid-electrolyte deficit during craniosynostosis repair is difficult owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was used in 4 ml kg(-1) h(-1) except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients (10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment of the primary craniosynostosis.     

Antisense inhibition of striatal GABAA receptor proteins decreases GABA-stimulated chloride uptake and increases cocaine sensitivity in rats

The functional status of striatal GABAA receptors appears to be inversely related to the magnitude of cocaine-induced behaviors. Exposure of striatum to antisense oligodeoxynucleotides (ASODNs) targeted to the mRNAs for the alpha 2 and the beta 3 subunits of the GABAA receptor should decrease expression of receptor proteins and therefore might be expected to increase cocaine sensitivity. ASODNs, scrambled ODNs or saline were injected into right lateral ventricle of rats and behavioral responses to cocaine were tested 18-20 h after treatment. Animals injected separately with alpha 2 or beta 3 ASODNs exhibited increased behavioral sensitivity to cocaine compared to rats injected with saline or scrambled ODNs including performing more 360 degrees turns to the left than to the right. There was significantly less GABA-stimulated Cl uptake in right striatum compared to left striatum of ASODN-treated rats with no significant difference between sides in control animals. Specific binding to benzodiazepine and convulsant sites on the GABAA receptor was not selectively altered by ASODN treatment. Combined alpha 2 beta 3 ASODN treatment did not affect either cocaine sensitivity or GABAA receptor function. There was no difference between the density of Nissl stained cells in the left and right edges of striatum in control or ASODN-treated rats indicating the absence of significant neurotoxic effects of the ASODN treatment. Injection of fluorescein-conjugated ASODNs indicated that ASODN is present in striatum at times during which behavioral and neurochemical indices of GABA receptor function are decreased. Thus, the functional status of GABAA receptors in striatum may be involved in determining cocaine sensitivity.     

Ratio of free-to-total prostate specific antigen in serum cannot distinguish patients with prostate cancer from those with chronic inflammation of the prostate

PURPOSE: We demonstrate the effect of chronic inflammation of the prostate on the ratio of free-to-total prostate specific antigen (PSA) in serum calculated as a percentage of free PSA and, therefore, that percentage of free PSA is an unspecific means to distinguish among prostate cancer, chronic prostatitis and benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Total, free and percentage of free PSA was measured in 66 men with prostate cancer, 119 with BPH and 17 with asymptomatic chronic prostatitis. In all patients the diagnosis was histopathologically confirmed by microscopic examination of prostatic specimens after sextant biopsy, transurethral prostatic resection or prostatectomy. RESULTS: The median values of total, free and percentage of free PSA were 4.11 microg./l., 0.75 microg./l. and 20.4% in patients with BPH, 10.0 microg./l., 0.84 microg./l. and 8.5% in those with prostate cancer, and 7.60 microg./l., 1.23 microg./l. and 10.6% in those with chronic prostatitis. Patients with prostate cancer and chronic prostatitis had a significantly lower percentage of free PSA than those with BPH. Receiver operating characteristics curve analysis showed that percentage of free PSA as a discriminator between prostate cancer and BPH was not suitable for differentiating between prostate cancer and chronic prostatitis. CONCLUSIONS: Chronic prostatitis is not characterized by elevated total PSA concentrations alone but also by a decreased percentage of free PSA, a tendency similar to that in prostate cancer. This unspecific change in percentage of free PSA must be considered to interpret the percentage of free PSA correctly.     

Ohmic contact and transport properties of II–VI Green/Blue laser diodes

The employment of the Zn(Se,Te) pseudo-graded contacting scheme to p-type ZnSe-based alloys contributes directly to the recent demonstration of room temperature continuous-wave operation of II– VI green-blue laser diodes. Contact ohmicity is maintained down to cryogenic temperatures which enabled the investigation of electrical transport properties associated with the p-type nitrogen-doped ZnSe, Zn(S,Se), and (Zn,Mg)(S,Se). The observation of both persistent photoconductivity and a metastable population of holes which are in thermodynamic equilibrium with hydrogenic acceptors having reduced activation energy suggests the presence of a DX-like behavior for holes in p-type (Zn,Mg)(S,Se).