A 286 mm2 256 Mb DRAM with ×32 both-ends DQ

This paper describes a 256 Mb DRAM chip architecture which provides up to ×32 wide organization. In order to minimize the die size, three new techniques: an exchangeable hierarchical data line structure, an irregular sense amp layout, and a split address bus with local redrive scheme in the both-ends DQ were introduced. A chip has been developed based on the architecture with 0.25 μm CMOS technology. The chip measures 13.25 mm×21.55 mm, which is the smallest 256 Mb DRAM ever reported. A row address strobe (RAS) access time of 26 ns was obtained under 2.8 V power supply and 85°C. In addition, a 100 MHz×32 page mode operation, namely 400 M byte/s data rate, in the standard extended data output (EDO) cycle has been successfully demonstrated     

An induced interaction model for arbitrarily polarized Fermi systems

A model for calculating the interactions in arbitrarily spin-polarized Fermi systems is presented. Starting from the four-point vertex functions, the induced part of the interactions is deduced by explicitly treating the one-particle, one-hole irreducible diagrams and using some general crossing symmetry relations. Extrapolation away from the Fermi surface is carried out by replacing the particle-hole phase space by Lindhard functions in the crossed channel; consequently, calculation of the necessary - phase space function is presented. The longitudinal spin-density and density responses for polarized systems are obtained by diagrammatic means. A possible way of treating the direct part of the interactions using Born approximation is also discussed. Finally, the limits of the model for zero and full polarization are given.     

Safety analysis of intermittent hemodialysis in patients with continuous flow left ventricular assist devices

Dialysis centers adopt a cautious approach when it comes to performing intermittent hemodialysis (HD) on patients with continuous flow (CF) left ventricular assist devices (LVADs) because of the potential for volume flux‐related complications and absence of pulsatile blood pressure for monitoring. Many patients have to remain hospitalized because of the inability of the dialysis centers to accept them for outpatient dialysis. In this study, the effect of HD was observed in such patients. Between June 2009 and October 2012, 139 patients received LVADs, of which 10 patients (7%) required intermittent HD postoperatively. The mean age of the patients was 53 ± 14 years and 90% were men. A total of 281 dialysis sessions were administered amounting to 1025 hours of dialysis. The mean systolic blood pressure monitored with Doppler device was 97 ± 18 mmHg. Dialysis durations averaged 218 ± 18 minutes. Mean blood flow rate was 334 ± 38 cc/min, and 2.6 ± 1.1 L was ultrafiltrated during each session. Only 15 (5.3%) sessions were interrupted or terminated in six patients. The reasons for termination were symptomatic hypotension—6 (2.1%), asymptomatic hypotension—3 (1%), ventricular tachycardia—1 (0.36%), dialysis machine malfunction—2 (0.7%), low phosphorus—2 (0.7%), and abdominal cramps—1 (0.36%). Volume expansion was necessary on three occasions. Low‐flow device alarms were registered during two (0.71%) sessions. The results showed no serious adverse effects or deaths.     

Ökologische Untersuchungen am Echten Hausschwamm und weiteren Hausfäulepilzen

Zusammenfassung Untersucht wurden die Letaltemperaturen von acht Hausfäulepilzen. Alle Pilze vertrugen in getrockneten Holzproben deutlich höhere Temperaturen als auf Agar: Donkioporia expansa und die Gloeophyllum-Arten überlebten vier Stunden 95°C, Antrodia vaillantii und Oligoporus placenta 80°C, Leucogyrophana mollusca und Coniophora puteana 70°C und Serpula lacrymans 65°C. Diese Befunde werden im Hinblick auf Heißluftbehandlungen diskutiert. Laborversuche und Beobachtungen aus über 40 Hausschwammbefällen in Gebäuden im Hamburger Raum zeigten nur geringen Wassertransport durch das Mycel. Bei S. lacrymans lag die maximale Befeuchtungsgeschwindigkeit bei drei Millimetern pro Woche. Die minimale Holzfeuchtigkeit für den Abbau von Kiefernholz betrug für S. lacrymans 26,2% u, das Optimum in der Initialphase 35–55% u und bei stärkstem Holzabbau 45–90% u; das Maximum lag über 220% u. Insgesamt wurden 37 verschiedene Hausfäulepilze nachgewiesen, sechs davon erstmals. S. lacrymans war der häufigste Pilz. In Gebäuden scheint sich eine Verschiebung im Artenspektrum zu Pilzen mit höheren Feuchtigkeitsansprüchen abzuzeichnen, die auch das Vorkommen von Schleimpilzen einschließt. Ein Zusammenhang mit dem verstärkten Wärmeschutz in Altbauten wird vermutet.

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Ecological investigations on Serpula lacrymans and other house rot fungi

The effect of increased temperatures was investigated for eight indoor wood decay fungi. All fungi survived in dried wood sticks at significantly higher temperatures than mycelium on malt agar. Donkioporia expansa and the Gloeophyllum species survived four hours at 95°C. Antrodia vaillantii and Oligoporus placenta survived at 80°C whereas Leucogyrophana mollusca and Coniophora puteana not above 70° and the true dry rot Serpula lacrymans not above 65°C. The results are discussed with regard to the treatment of buildings with hot air. Laboratory tests and observations from over 40 attacks in buildings of the area of Hamburg were evaluated. For S. lacrymans, only a slight transport of water through the mycelium could be detected. The maximum humidification speed of this fungus was three millimetres per week. The minimal measured wood moisture of pinewood for wood decay was 26.2% u. The optimal moisture for wood decay by S. lacrymans was 35–55% u in the initial phase and 45–90% u later. The maximum wood moisture with wood mass loss greater than 2% was more than 220% u. Thirty-seven different fungi were found in buildings. Six fungi have been shown for the first time in buildings. The true dry rot fungus was the most frequent fungus with a frequency of about 46%. In buildings, the spectrum of the species seems to change. Fungal species demanding relatively higher moisture are again found more frequently these days. The occurrence of slime fungi also seems to rise. The possible connection with the higher thermoprotection in old buildings after reconstructions is discussed.

     

A 125-mm/sup 2/ 1-Gb NAND flash memory with 10-MByte/s program speed

A single 3-V only, 1-Gb NAND flash memory has been successfully developed. The chip has been fabricated using 0.13-/spl mu/m CMOS STI technology. The effective cell size including the select transistors is 0.077 /spl mu/m/sup 2/. To decrease the chip size, a new architecture is introduced. The in-series connected memory cells are increased from 16 to 32. Furthermore, as many as 16 k memory cells are connected to the same wordline. As a result, the chip size is decreased by 15%. A very small die size of 125 mm/sup 2/ and an excellent cell area efficiency of 70% are achieved. As for the performance, a very fast programming and serial read are realized. The highest program throughput ever of 10.6-MByte/s is realized: 1) by quadrupling the page size and 2) by newly introducing a write cache. In addition, the garbage collection is accelerated to 9.4-MByte/s. In addition, the write cache accelerates the serial read operation and a very fast 20-MByte/s read throughput is realized.