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Background: Recently, a combination prescription with the main ingredients sitagliptin and dapagliflozin as dipeptidyl peptidase-4 andsodium?glucose cotransporter-2 inhibitors, respectively, for the treatment of type 2 diabetes has widely been issued in hospitals. However, the development of double-layered tablets requires simultaneous quantitative dissolution tests that are significantly efficient and cost-effective.Objective: Individual analysis of the two active pharmaceutical ingredients (APIs) incurs more than twice the time and cost. Consequently, this study aimed to develop a dissolution analysis method that simultaneously quantifies the APIs dapagliflozin and sitagliptin in multi- layered tablets. This simultaneous quantitative dissolution analysis can dramatically reduce analysis time and cost.Methods: For reversed-phase high-performance liquid chromatography (RP-HPLC) analysis using ultraviolet detection, a Zorbax C18 column (4.6 × 150 mm, 5 µm) was used, and the flow rate was 1.5 mL/min, injection amount 20 µL, and maximum absorption wavelength set to 205 nm. Additionally, the analysis time was set to 1.5 times the retention time of dapagliflozin.Results: The retention times of dapagliflozin and sitagliptin were 11.57 and 2.56 min, respectively. Further, their relative standard deviations were 0.11% and 0.05%, respectively. Quantitative analysis using RP-HPLC confirmed no peak interference between the APIs and excipients. Both APIs exhibited linearity at a 20?120% concentration.Conclusion: The dissolution method developed in this study can quantify both APIs simultaneously, thereby reducing analysis time and cost by more than 50% and increasing efficiency in the pharmaceutical industry.

There are growing populations of Korean children who studied abroad in the English as a second language (ESL) context and had to return to Korea for various reasons before reaching college age. These returnees are concerned about how to maintain (or improve) their English proficiency in the EFL (English as a foreign language) context. The purpose of this qualitative case study was to investigate two Korean-English bilinguals who recently returned to Korea after learning English in the US for more than four years. The research questions were as follows: 1) How do Korean returnees perceive the change of learning status as Korean-English bilinguals in the US and Korea, and 2) What motivated Korean returnees to sustain their English proficiency while acquiring academic literacy in Korean? By using the case study method, an extensive and in-depth description of two Korean returnees’ English language learning experiences was provided. Data were collected through semi-structured interviews and observation. The analysis showed that the switch from ESL to EFL learning environments, which includes the change of language, culture, and social contexts, influenced how Korean returnees maintain/improve their English proficiency, specifically with their language learning strategies (LLS).

In the chicken, Dominant white is one of the major loci affecting feather color. Germline chimeric chickens are identified by testcross analysis using this genetic marker. The testcross, however, is a time‐consuming and laborious procedure, resulting in the need for a faster and simpler molecular method. A recent study showed that Dominant white was exclusively associated with a 9‐bp insertion in the PMEL17 gene. We searched for breed‐specific sequence polymorphisms in the PMEL17 gene among White Leghorn (WL) (white feather), Korean Ogol Chicken (KOC) (black feather), and Barred Plymouth Rock (grayish‐white, each feather regularly crossed with parallel blue‐black bars). In addition to the 9‐bp insertion, WLs and KOCs have unique bases in single nucleotide polymorphisms (SNPs) at the 1,777th and 3,118th bases in the PMEL17 gene. To detect these sequence polymorphisms, allele‐specific polymerase chain reaction (AS‐PCR) was performed, which successfully distinguished the different breeds. We confirmed the ability of the AS primers to detect germline chimerism. This simple method can be widely used for the screening of germline chimeric chickens. J. Exp. Zool. 307A:241–248, (2007). © 2007 Wiley‐Liss, Inc.

Much research has been done on the cues differentiating the three Korean stops in word initial position. This paper focused on a more neglected area: the acoustic cues differentiating the medial tense and lax unaspirated stops. Four adult Korean native speakers, two males and two females, pronounced 16 minimal pairs containing these stops. The average duration of vowels before lax stops is 93 ms longer than before their tense counterparts (143 ms for lax versus 50 ms for tense). In addition, the average duration of the stop closure of tense stops is 178 ms longer than that of lax stops (74 ms for lax versus 252 ms for tense). These durational differences are so large that they may be phonologically determined, not phonetically. Moreover, vowel duration may vary with the speaker’s sex. Female speakers have much shorter vowel duration before the lax stops. The quality of voicing, tense or lax, is also a cue to these two stop types, as it is in initial position, but the relative duration of the stops and of the preceding vowel appear to be much more important cues. The consequences of these results for the phonological description of Korean as well as the synthesis and automatic recognition of Korean will be discussed.

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