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Functional brain imaging studies have suggested that the superior temporal gyrus (STG) and the middle temporal gyrus (MTG) are involved in phonological and lexical-semantic processing, respectively. However, the precise role of the posterior temporal lobe is not fully understood. To clarify the functional relevance of the left posterior STG and MTG during language processing, we used neuronavigation-guided repetitive transcranial magnetic stimulation (rTMS). The reaction times and error rates for 12 healthy volunteers performing auditory repetition and lexical-semantic decision tasks were compared before and during rTMS stimulation. We applied 1 Hz rTMS over the left posterior STG or MTG or sham stimulation for 10 min in a random order. Stimulation of the left posterior MTG significantly slowed the response time for the lexical-semantic decision task from 478.9±56.5 to 583.1±80.0 ms. However, stimulation over the left posterior STG or MTG did not affect the response time or the error rate for the auditory repetition task. Our results suggest that the left posterior MTG might be involved in lexical decision making. Neuronavigation-guided rTMS virtual lesion studies could help determine the functional roles of specific brain areas in language processing, and our findings provide new evidence supporting the use of neuromodulation through rTMS for patients with aphasia.

Benthic macroinvertebrates are considered as a representative taxon that indicates the ecological status of freshwater ecosystems. Numerous indices derived from community data have been proposed to estimate either biological water quality or ecosystem health. In this study, metrics based on benthic macro- invertebrates at the family level were screened using ecological informatics to provide a multi-metric measurement that would be suitable for presenting ecological integrity across different levels of environmental impact. Benthic macroinvertebrates were collected at a total of 720 sample sites from river basins and streams in Korea in 2009. Based on four categories of community status (i.e., diversity, richness, tolerance, and composition), 37 metrics were selected as initial candidates according to the literature. The candidate metrics were evaluated according to parameters including discriminatory power, redundancy, and responsiveness to stressors. Self-organizing map was utilized to assist the screening procedure by providing ordination, clustering, and visualization of metric and environmental data. Six metrics were finally selected as a multi- metric and were compared with conventional indicators for presenting the ecological integrity of streams.

Escherichia coli is the most frequently identified microbiological agent in childhood urinary tract infections (UTIs). However, the pathogenic role of this organism in young children remains to be clearly elucidated. So far, no studies have been conducted in which multiplex polymerase chain reaction (PCR) has been applied to determine the association between childhood UTIs and E. coli and urovirulent genes.Altogether, 330 suprapubic urine specimens from febrile young children were cultured. In 33 of the cases, E. coli was identified; among these cases, 18 had a UTI (10(4)-10(5) cfu/ml), four had a suspected UTI (10(2)-10(3) cfu/ml) and 11 did not have UTIs (10(2) cfu/ml). Using multiplex PCR, three uropathogenic E. coli (UPEC) genes and two enteroaggregative E. coli (EAEC) genes were detected.In the UTI-UPEC cases, the kps gene was detected in 18 of 22 cases (82%) and the usp gene in 16 of 22 cases (73%). Among the 18 cases of children with UTIs characterized by 10(4)-10(5) E. coli cfu/ml, urinary tract abnormalities were identified via dimercaptosuccinic acid scans in seven of 18 cases (39%) and via voiding cystourethrograms in four of the 18 cases (22%).The UPEC kps and usp genes were clearly associated with childhood UTIs, and may also be associated with kidney or urinary tract dysfunctions in young children. Escherichia coli colony count numbers in excess of 10(4)-10(5) cfu/ml in the suprapubic urine were considered to be strong evidence of UTI in infants.

Intensive speech therapy improves language function in patients with chronic aphasia, although treatment in the acute phase is more effective than in the chronic phase. Unfortunately, most patients with stroke go untreated due to socioeconomic problems. This study was performed to develop and test a speech therapy-based telerehabilitation program (iAphasia), suitable for use on a mobile device platform, which would expand access to therapy to patients who frequently go untreated.We enrolled 8 patients with chronic poststroke aphasia to receive therapy via our iPad(®) (Apple, Cupertino, CA)-based telespeech therapy program, iAphasia. Participants received 4 weeks of telespeech therapy using iAphasia, which generates six domains with six levels of difficulty. We compared pre- and posttreatment scores on the Korean version of the Western Aphasia Battery (K-WAB) to evaluate effectiveness. Additionally, a 1-month follow-up assessment was performed.We investigated user satisfaction using a questionnaire to assess the feasibility of iAphasia. After the 4-week treatment, language function as measured by the K-WAB improved significantly. The improvement was persistent at the 1-month follow-up visit. The degree of improvement was strongly associated with usage time, regardless of participants' age and severity of aphasia. Overall, satisfaction with iAphasia was rated high.The results from this study suggest it to be an effective and feasible treatment method for chronic aphasia, although follow-up studies with more subjects and a control group are needed for a more thorough assessment.

Early identification of patients with stroke-induced aphasia is essential because it is a significant disability affecting daily life and is linked to poor functional outcome after stroke. However, most patients with stroke are unable to undergo aphasia evaluation and detection and therefore remain undiagnosed. The purpose of this study is to develop a valid, reliable mobile aphasia screening test (MAST) for patients in remote locations.To accomplish this, we enrolled patients with (n=30) and without (n=30) stroke-induced aphasia. A MAST, which adopted the Korean version of the shortened version of the Frenchay Aphasia Screening Test (K-FAST), was designed as an iPad(®) (Apple, Cupertino, CA) application. To validate the MAST, we compared its performance with that of the Korean version of the Western Aphasia Battery (K-WAB) and conventional shortened FAST paper version (K-FAST). We analyzed interrater and internal reliability, using Cronbach's alpha coefficient, and assessed the diagnostic sensitivity, specificity, and power.There was significant correlation between K-FAST and MAST (intraclass correlation coefficient [ICC]=0.995, p0.001). MAST also had a high correlation with K-WAB (ICC=0.752, p0.001). Interrater reliability was very high (ICC=0.999, p0.001). The test had high sensitivity (90.0%) and specificity (73.3%) with an accuracy of 0.930 (95% confidence interval=0.853-1.000). The MAST is a valid and reliable tool for detecting aphasia in patients with stroke.This telescreening test may overcome the limitations of test administration and may be a convenient and cost-effective alternative to the existing aphasia screening tests for patients with stroke.

The aim of this study was to compare the serum cytokine profiles of Plasmodium vivax malaria patients who presented with and without hepatic dysfunction. This is a retrospective analysis of 74 consecutive cases of P. vivax malaria seen at 3 military hospitals near the Demilitarized Zone in South Korea from 1999 to 2000. All patients studied were adult active duty servicemen. On admission, the mean (+/- SEM) age of the patients who presented with (n = 36) and without hepatic dysfunction (n = 38) was 21.6 +/- 0.24 and 22.5 +/- 0.44 years, respectively (P = 0.72). On admission, there was no significant difference between the 2 patient populations in terms of mean temperature, haemoglobin level, haematocrit, total white blood cell count, platelet count, parasite index, and serum concentration of transforming growth factor-beta. Plasmodium vivax malaria patients who presented with hepatic dysfunction had significantly higher mean serum concentrations of soluble Fas ligand, interleukin (IL)-l, IL-4, IL-6, IL-10, tumor necrosis factor-alpha, and interferon-gamma than those without hepatic dysfunction, suggesting the involvement of these cytokines in the development of hepatic dysfunction. The mean serum concentration of IL-12 was significantly lower in patients with hepatic dysfunction. The mean body temperature was not significantly different between the 2 patient populations.

Serum cytokine profiles in patients with Plasmodium vivax malaria who presented with and without hyperpyrexia were compared by a retrospective review of the medical records of the consecutive patients seen at the military hospitals near the demilitarized zone in the Republic of Korea from April 2000 through October 2001. Of 162 male patients studied, 120 (86.4%) presented with hyperpyrexia (i.e., an axillary temperatureor = 40 degrees C). The mean +/- SEM ages of the patients with and without hyperpyrexia were 21.5 +/- 0.14 and 21.9 +/- 0.39 years, respectively (P = 0.33). The mean +/- SEM concentrations of serum interleukin (IL)-6 (379.7 +/- 44.1 pg/mL versus 105.4 +/- 26.8 pg/mL; P = 0.002), IL-10 (583.4 +/- 58.2 pg/mL versus 142.4 +/- 39.7 pg/mL; P = 0.0001), and interferon-gamma (312.6 +/- 33.9 pg/mL versus 112.9 +/- 27.1 pg/mL; P = 0.0001) were significantly higher in patients with hyperpyrexia compared with those without hyperpyrexia. The mean +/- SEM concentrations of serum tumor necrosis factor-alpha were 155.5 +/- 54.5 pg/mL and 109.9 +/- 29.3 pg/mL (P = 0.27) in patients who presented with and without hyperpyrexia, respectively. Further studies are needed to examine whether serum concentrations of these cytokines also parallel their concentrations at the tissue sites of their production and action.

Objective To delineate the changes in corticospinal excitability when individuals are asked to exercise their hand using observation, motor imagery, voluntary exercise, and exercise with a mirror. Method The participants consisted of 30 healthy subjects and 30 stroke patients. In healthy subjects, the amplitudes and latencies of motor evoked potential (MEP) were obtained using seven conditions: (A) rest; (B) imagery; (C) observation and imagery of the hand activity of other individuals; (D) observation and imagery of own ipsilateral hand activity; (E) observation and imagery of the hand activity of another individual with a mirror; (F) observation and imagery of own symmetric ipsilateral hand activity (thumb abduction) with a mirror; and (G) observation and imagery of own asymmetric ipsilateral hand activity (little fi nger abduction) with a mirror. In stroke patients, MEPs were obtained in the A, C, D, E, F conditions. Results In both groups, increment of the percentage MEP amplitude (at rest) and latency decrement of MEPs were significantly higher during the observation of the activity of the hand of another individual with a mirror and during symmetric ipsilateral hand activity on their own hand with a mirror than they were without a mirror. In healthy subjects, the increment of percentage MEP amplitude and latency decrement were signifi cantly higher during the observation of the symmetric ipsilateral hand activity with a mirror compared to the observation of the activity of the asymmetric ipsilateral hand with a mirror of their own hand. Conclusion In both groups, corticospinal excitability was facilitated by viewing the mirror image of the activity of the ipsilateral hand. Th ese fi ndings provide neurophysiological evidence supporting the application of various mirror imagery programs during stroke rehabilitation.

We report on the fabrication and characterization of Al0.1Ga0.9N/GaN heterojunction field effect transistors, both an enhancement mode and a depletion mode with a low pinchoff voltage, suitable for digital integrated circuit applications. For an enhancement mode device with a 1 μm gate length and 5 μm drain‐to‐source separation, the dc transconductance is around 23 mS/mm. Connecting the enhancement mode device as a switching transistor and a depletion mode device as a load, we demonstrate an AlGaN/GaN inverter.

Objective: To investigate the influence of associated medical diseases and complications on functional improvement after in-patient through stroke rehabilitation. Method: We performed a retrospective analysis on medical records of 183 stroke patients who had admitted to the department of rehabilitation medicine. Functional Independence Measure (FIM), Modified Barthel Index (MBI) at admission and discharge were used to assess the functional status. We investigated medical diseases, such as hypertension, diabetes, myocardial infarct, atrial fibrillation osteoarthritis, rheumatoid arthritis, previous history of stroke and complications such as dementia, post-stroke depression, central post-stroke pain, complex regional pain syndrome, neglect and aphasia. Results: Post-stroke patients with myocardial infarct, atrial fibrillation, osteoarthritis, dementia, aphasia and neglect significantly showed lower gain of FIM and MBI, lower FIM and MBI efficacy during inpatient rehabilitation compared to without those (p 0.05). Total numbers of associated medical diseases and complications negatively affect on FIM and MBI efficacy (p