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Pressurized membrane module systems, including hollow fiber type of Microfiltration (MF) and Ultrafiltration (UF) membranes are being increasingly used in drinking water treatment due to their high removal efficiency of pathogen. However, when fibers are damaged in pressurized membrane system, the pathogen will be able to penetrate the membrane. Therefore, it is essential to guarantee the regulatory requirements for water quality by an effective on-line or off-line condition integrity monitoring methods. Recently, pressure decay test (PDT) which is one of membrane integrity tests has been reflected to drinking water treatment plants using pressurized membrane module. In this paper, three different method were used to perform PDT and three different sensitivity values were analyzed through experiments. Three types of direct integrity test methods were applied to pressure feed side, filtrate side and bidirectional pressure decay test. The results of these experiments show that the sensitivity was increasing when the volume of pressurized gas was decreasing. The sensitivity is inversely proportional to the gas volume. Furthermore, it is desirable to increase pressure difference between feed side and permeate side in order to achieve higher sensitivity in the PDT by membrane damage.

Conjectures are made on the origins of linking consonants in Mongolic intensive adjectives. It is argued that Dagur ?im ?igaan ‘snow-white’ and Khalkha bas bat ‘very firm,’ previously claimed to possess linking /m/ and /s/, are not really intensive adjectives but adjectives modified by intensifying adverbials ?im and bas, which happen to resemble the emphatic prefixes formed by CV-reduplication and addition of linking /m/ or /s/. Two evidences in support of this claim are adduced: 1) ?im and bas are the only examples in each language that carry such ‘exotic’ linker among Mongolic languages, which generally use only /b/, e.g. ?ab ?agaan ‘snow-white’; 2) a comparative study of Turkic and Mongolic intensifiers suggests that Dagur ?im is likely to be related to Turkmen cim in, e.g. Turkmen cim a:k ‘very white’, while bas may be a doublet of Khalkha ma? ‘extremely’. The three-way variation of linker in Kalmuck bim bitu ~ bis bitu ~ biŋ bitu ‘completely closed’, on the other hand, indicates that: 1) the dissimilative constraint preventing default /b/ as a linker in labial-initial bases in Mongolic is being relaxed in Kalmuck; 2) the choice of /m/ and /s/ as an alternative linker to the default /b/ is probably due to influence from neighboring Turkic languages that have linking /m/ and /s; 3) the use of linking /ŋ/ reflects an effort by the Kalmuck speakers to avoid another labial /m/ in compliance of the dissimilation constraint. It is concluded that Mongolic generally use only /b/ (or its variant /w/) for its linking consonant, and other apparent linkers are all alternatively explained. It is hypothesized on this conclusion that if Mongolic borrowed its intensive formation from Turkic, as is generally agreed, it was during the early Turco-Mongolic contact and the rule was transferred from non-Oghuz Old Turkic, which, like Mongolic, had default labial /p/ as the only linking consonant.

The incidence of detection of accessory hepatic vein (AHV) using MRI or CT has been reported. However, previous studies had a small sample size or only reported on the incidence of hepatic vein variants. To the best of our knowledge, there has been no previous report evaluating the factors predictive of the presence of an AHV. To evaluate the incidence and morphology of the accessory hepatic vein (AHV) using multidetector row computed tomography (MDCT) and to investigate the factors which may be helpful in predicting the presence of an AHV. We enrolled 360 patients who underwent abdominal MDCT. We investigated whether the AHV was present and evaluated the frequency of AHVs greater than 5 mm in diameter. We classified the morphology of the AHV entering the inferior vena cava (IVC). We also examined the factors that predicted the presence of an AHV by comparing the diameter of the middle hepatic vein (MHV) and the right hepatic vein (RHV). We identified an AHV in 164 of the 360 patients (45.6 %). Among the 164 AHVs, 56.7 % were larger than 5 mm in diameter. The most common morphologies of the inferior RHV were a single main trunk (58.5 %), followed by two main trunks with a V-shape (19.5 %) and two trunks entering the IVC separately (17.0 %). The possibility that an AHV will be present was significantly higher when the diameter of the RHV was smaller than that of the MHV. MDCT can provide important information regarding AHV incidence and morphology. The possibility of an AHV being present was significantly higher when the diameter of the RHV was smaller than that of the MHV. Se ha informado de la incidencia de la detección de la vena hepática accesoria (VHA) mediante RM o TC. Sin embargo, estudios previos tenían un tamaño muestral pequeño o solo informaban sobre la incidencia de variantes de las venas hepáticas. Hasta donde sabemos, no ha habido ningún informe previo que evalúe los factores predictivos de la presencia de una VHA. El objetivo del estudio fue evaluar la incidencia y morfología de la vena hepática accesoria (VHA) mediante tomografía computarizada multidetector (TCMD) e investigar los factores que pueden ser útiles para predecir la presencia de un VHA. Se evaluaron 360 pacientes que se sometieron a TCMD abdominal. Se investigó si la VHA estaba presente y se evaluó la frecuencia de VHA mayores de 5 mm de diámetro. Se clasificó la morfología del VHA que drenaba en la vena cava inferior (VCI). Además, se examinaron los factores que predijeron la presencia de una VHA mediante la comparación del diámetro de la vena hepática media (VHM) y la vena hepática derecha (VHD). Se identificó un VHA en 164 de los 360 pacientes (45,6%). Entre las 164 VHA, el 56,7% tenía más de 5 mm de diámetro. Las morfologías más frecuentes del VHD inferior fueron un tronco principal único (58,5%), seguido por dos troncos principales con forma de V (19,5%) y dos troncos que drenaban en la VCI por separado (17,0%). La posibilidad de que una VHA esté presente fue significativamente mayor cuando el diámetro de la VHD era menor que la de la VHM. La MDCT puede proporcionar información importante sobre la incidencia de la VHA y su morfología. La posibilidad de que un VHA estuviera presente era significativamente mayor cuando el diámetro del VHD era menor que la VHM.