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Candida albicans is an opportunistic human pathogen that exists as yeast, hyphal or pseudohyphal forms depending on pH, nutrients, and temperature. The morphological transition from yeast to hyphae, which is required for the complete virulence of C. albicans, is controlled by many transcription factors that activate or repress hypha-specific genes. The C. albicans transcriptional factor Cas5, a key regulator of genes involved in cell wall integrity, affects the susceptibility of C. albicans to fluconazole, an inhibitor of ergosterol synthesis. In this study, we found that deletion of CAS5 in C. albicans decreased the expression levels of a set of ergosterol biosynthesis genes, such as ERG2, ERG3, ERG5, ERG6, ERG11, and ERG24, resulting in the accumulation of lanosterol and zymosterol, which are intermediate metabolites in the ergosterol biosynthesis pathway. Interestingly, it was observed that the cas5Δ/Δ mutant could not maintain the yeast form under non-hypha-inducing conditions, while the CAS5-overexpressing cells could not form hyphae under hypha-inducing conditions. Consistent with these observations, the cas5Δ/Δ mutant highly expressed hypha-specific genes, ALS3, ECE1, and HWP1, under non-hypha-inducing conditions. In addition, CAS5 transcription was significantly downregulated immediately after hyphal initiation in the wild-type strain. Furthermore, the cas5Δ/Δ mutant reduced the transcription of NRG1, which encodes a major repressor of hyphal morphogenesis, while Cas5 overexpression increased the transcription of NRG1 under hypha-inducing conditions. Collectively, this study suggests the potential role of Cas5 as a repressor of hypha-specific genes during yeast-form growth of C. albicans.

This study validates behavior development screening for toddlers (BeDevel), which utilizes a combination of short caregiver interviews (BeDevel-I) and semistructured play observations (BeDevel-P). The data of 431 toddlers (male 66.2%; mean age (SD) = 29.11 (8.59) months; ASD, n = 201; developmental delay, n = 46; typically developing, n = 184), aged 18 ~ 42 months, were included in the validation of BeDevel. The best clinical estimate diagnosis, screening rate, validity, sensitivity, and reliability of BeDevel were determined based on data cross-sectionally collected using BeDevel and existing diagnostic/screening instruments: autism diagnostic observation schedule (ADOS), autism diagnostic interview (ADI-R), Vineland adaptive behavior scales-II (VABS-II), social response scales (SRS), sequenced language scale for infants (SELSI), Korean childhood autism rating scale (K-CARS), and Korean social communication questionnaire (K-SCQ). The k values of BeDevel-I and BeDevel-P were 0.055 ~ 0.732 and 0.291 ~ 0.752, respectively. Items related to social referencing in BeDevel-P had a particularly high diagnostic validity (k = 0.483 ~ 0.684). Reliabilities of BeDevel-I and BeDevel-P were sufficient (Cronbach's alpha = 0.86 ~ 0.88 and 0.92 ~ 0.95, respectively). BeDevel-I and BeDevel-P showed high sensitivity (BeDevel-I: 85.00 ~ 89.29%; BeDevel-P: 85.00 ~ 91.75%), specificity (BeDevel-I: 77.55 ~ 89.55%; BeDevel-P: 85.09 ~ 97.01%), PPV (BeDevel-I: 70.83 ~ 88.54%; BeDevel-P: 81.52 ~ 94.68%), and NPV (BeDevel-I: 76.00 ~ 95.24%; BeDevel-P: 84.62 ~ 95.45%). The agreement between the composite BeDevel score and ADOS, ADI-R, K-CARS, and K-SCQ was >67.6% (range = 67.6 ~ 90.8%). Combining a short caregiver interview and direct play observation is a valid and reliable screening process. More studies on social referencing as an important early marker are needed. BeDevel can be utilized as a secondary screening instrument before diagnostic confirmation in clinical and community settings. LAY SUMMARY: BeDevel, which consists of a short caregiver interview and direct play observation, is a valid and reliable screening instrument for autism spectrum disorder (ASD). We suggest that BeDevel can be utilized as a secondary instrument before administering diagnostic assessments in clinical and community settings. More studies examining social referencing as a potential behavioral marker of ASD are needed.

Objective This study aimed to examine the validity of the Korean version of the Autism Diagnostic Interview-Revised (K-ADI-R) and determine its efficacy in identifying individuals with autism spectrum disorder (ASD).Methods Data were pooled from several past and ongoing studies as well as clinical records acquired at Seoul National University Bundang Hospital from 2008 to 2017. The K-ADI-R were administered and scored by trained research reliable examiners. Measurements to investigate the validity of the K-ADI-R was through sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and Cohen’s kappa.Results A total of 1,271 (age 88.9±62.42 months, male=927) participants were included. The K-ADI-R yielded strong psychometric properties with high sensitivity (86.06–99.27%), specificity (84.75–99.55%), PPV (92.33–99.72%), and NPV (79.43–98.64%). There were significant differences in item scores across the K-ADI-R diagnostic algorithm regardless of age and sex (p

Objectives The detection of autism spectrum disorder (ASD) is based on behavioral observations. To build a more objective datadriven method for screening and diagnosing ASD, many studies have attempted to incorporate artificial intelligence (AI) technologies. Therefore, the purpose of this literature review is to summarize the studies that used AI in the assessment process and examine whether other behavioral data could potentially be used to distinguish ASD characteristics. Methods Based on our search and exclusion criteria, we reviewed 13 studies. Results To improve the accuracy of outcomes, AI algorithms have been used to identify items in assessment instruments that are most predictive of ASD. Creating a smaller subset and therefore reducing the lengthy evaluation process, studies have tested the efficiency of identifying individuals with ASD from those without. Other studies have examined the feasibility of using other behavioral observational features as potential supportive data. Conclusion While previous studies have shown high accuracy, sensitivity, and specificity in classifying ASD and non-ASD individuals, there remain many challenges regarding feasibility in the real-world that need to be resolved before AI methods can be fully integrated into the healthcare system as clinical decision support systems.

Objective The purpose of this study was to examine the visuospatial processing abilities of children with autism spectrum disorder (ASD) using the Rey Osterrieth Complex Figure (ROCF).Methods One-hundred thirty-four children with ASD [mean age (MA)=113.56 months], 150 siblings of children with ASD (MA= 111.67 months), and 55 typically developing (TD) children (MA=109.02 months) were included in this study. During their one-time visit, participants completed the ROCF, various autism diagnostic assessments, and the Korean-Leiter International Performance ScaleRevised. Repeated-measures Analysis of Covariance (ANCOVA) and post-hoc Tukey-Kramer comparisons were computed to compare the ROCF scores. Partial correlations and multiple regressions were computed to examine the association between ROCF scores and the severity of autistic symptoms, as measured by the Autism Diagnostic Interview-Revised (ADI-R) among children with ASD.Results There were significant main effects of the analysis group in Structural and Incidental Accuracy, Error, and Style. More siblings than TD children drew in a part-oriented way, but the performance of the sibling group was comparable or superior to that of the TD group in all parameters. Social Interaction scores of children with ASD were significantly associated with Organization scores in Copy condition. Whether or not a child drew in the Part-Oriented style significantly predicted his/her repetitive and restricted behavior scores.Conclusion The findings add to the evidence for altered visuospatial processing patterns of ASD as a potential inherent and genetic trait and suggest that this particular cognitive style should not be considered as a deficit. Educational and theoretical implications are discussed.

Objective This study examined how state and trait anxiety of adolescents with autism spectrum disorders (ASD) are associated with their demographic characteristics, repetitive and restricted behaviors (RRBs), and internalizing and externalizing problem behaviors.Methods A total of 96 participants with ASD (mean age=14.30 years; 91 males) completed a battery of tests including the State/Trait Anxiety Inventory (STAI), the Autism Diagnostic Interview-Revised, the Social Responsiveness Scale (SRS), and a cognitive test measuring intelligence quotient (IQ). Participants’ parents completed the Child Behavior Checklist (CBCL). Pearson’s correlations among age, IQ, two subscales of the STAI (i.e., STAIS and STAIT, measuring self-reported state and trait anxiety, respectively), and the Anxiety subscale of CBCL (i.e., CBCL-Anxiety, measuring parent-reported trait anxiety) were computed. Subsequently, Pearson’s correlations were computed among the three anxiety measures, RRBs, and problem behaviors, while controlling for participants’ age and IQ.Results The STAIS and CBCL-Anxiety were both significantly correlated with higher age, sensory sensitivity, depressive symptoms, somatic complaints, and aggressive behaviors. All three anxiety variables were significantly and positively correlated with total SRS RRB scores. Additionally, the STAIS and STAIT were significantly associated with more severe Compulsion/Adherence behaviors, and the CBCL-Anxiety was also significantly associated with more severe Rule-breaking Behaviors.Conclusion Self-reported state anxiety showed association patterns similar to those of parent-reported trait anxiety. Future studies investigating the precise operationalization of different anxiety instruments are needed to accurately measure the anxiety of adolescents with ASD.

Background Previous works attempting to document sex differences in younger children with autism spectrum disorder (ASD) have yielded inconsistent results. Therefore, this study aimed to investigate potential sex differences in the manifestation of ASD-related features in toddlers and preschoolers with ASD, typical development (TD), and other developmental disorders (OD). Method Analyses were conducted using a sample of 557 young children, aged 18−42 months, composed of 261 participants with ASD (n = 207 males; n = 54 females), 223 TD (n = 133 males; n = 90 females), and 73 with OD (n = 45 males; n = 28 females). A battery of tests, including the gold standard ASD diagnostic assessments and caregiver questionnaires, were used to measure symptomatology. We implemented ANCOVA while covarying for adaptive skills to detect sex differences in ASD trait presentation. Results The ASD group demonstrated significant differences in the parent-report social interaction domain with more deficits in females than males, while the TD and OD groups found that males exhibited more restricted or repetitive behaviors (RRB) than females. When the participants were limited to children over 24 months to ensure good diagnostic validity, the same patterns in traits by sex were observed, except in the OD group, suggesting that the younger children might have driven the significant findings. Conclusion Sex differences in the social interaction domain were reported by parents of children with ASD, while children in the non-ASD groups exhibited differences in RRBs. Therefore, healthcare professionals should become aware of the different presentational profiles in young children to prevent over or under detection of ASD.

In this work, the nutation control of rigid spacecraft with only two momentum wheels is addressed by applying the feedback linearization technique. In this strategy, the primary performance index is to regulate the nutational angle by the momentum control of wheels. The spacecraft attitude equations of motion are transformed to a general linearized form by feedback linearization technique, including a guaranteed control law promising the internal dynamics stability to accomplish the nutation angle small. It is proven that the configuration of inertia properties plays a key role in analyzing spacecraft energy level. The behavior of the momentum wheels is also studied analytically and numerically. Finally, the effectiveness of the proposed nonlinear control law for the momentum transfer is verified by conducting numerical simulations.

AnewtechniqueforAttitude&HeadingReferenceSystem(AHRS)byusingsequentialmeasurementnoisecovariance(SMNC)isaddressedinavibrationenvironmentsinthispaper. Inparticular, alow-costinertialmeasurementunitingeneraldivergesintheaccelerationphaseorvibratingenvironmentsduetoinherentpropertiesofgravityandacceleration.Inthispaper,byconsideringcurrentandpriormeasurementstoestimateactualattitudesandheadingsinalocalframe,theproposedtechniqueovercomestheseproblemsefficiently.Finally,theperformanceofthesuggestedapproachisverifiedbynumericalsimulations. 초 록 본 논문은 관성 항법 시스템(InertialNavigationSystem)을 활용한 자세 및 방향 결정시스템(Attitude&HeadingReferenceSystem)의 성능을 향상시키기 위한 새로운 기법인,순차적 측정 오차 공분산(SequentialMeasurementNoiseCovariance)기법을 제시하였다.관성 센서는 시간이 지남에 따라 발생하는 적분오차와 진동이나 가속구간과 같은 외란이 가해 졌을 때 성능이 저하된다는 단점이 있다.특히,저가의 관성 센서의 경우 이러한 현상이 더욱 두드러지게 나타난다.이를 극복하기 위한 알고리즘들은 많이 존재한다.하지만 가장 일반적으로 사용되는 확장 칼만 필터의 경우 가속도계를 사용할 때 측정값(Measurement)이 일정 범위를 넘어가면 센서값을 배제하는 방법을 사용한다.본 논문에서 제안하는 기법은 범위를 설정하지 않고 과거의 데이터를 순차적으로 활용하여 측정값의 가중치를 변화하는 기법이다.최종적으로 제안된 기법을 수치 시뮬레이션을 통해 검증하였다.KeyWords:ExtendedKalmanFilter(확장칼만필터),AdaptiveFilter(적응 필터),INS(관성 항법 시스템),AttitudeEstimation(자세 추정),AHRS(Attitude&HeadingReferenceSystem)

NDR (nuclear Dbf2-related) kinases are essential components for polarized morphogenesis, cytokinesis, cell proliferation, and apoptosis. The NDR kinase Cbk1 is required for the hyphal growth of Candida albicans ; however, the molecular functions of Cbk1 in hyphal morphogenesis are largely unknown. Here, we report that Cbk1 downregulates the transcriptional repressor Nrg1 through the mRNA-binding protein Ssd1, which has nine Cbk1 phosphorylation consensus motifs. We found that deletion of SSD1 partially suppressed the defective hyphal growth of the C. albicans cbk1 Δ/Δ mutant and that Ssd1 physically interacts with Cbk1. Cbk1 was required for Ssd1 localization to polarized growth sites. The phosphomimetic SSD1 allele ( ssd1-9E ) allowed the cbk1 Δ/Δ mutant to form short hyphae, and the phosphodeficient SSD1 allele ( ssd1-9A ) resulted in shorter hyphae than did the wild-type SSD1 allele, indicating that Ssd1 phosphorylation by Cbk1 is important for hyphal morphogenesis. Furthermore, we show that the transcriptional repressor Nrg1 does not disappear during hyphal initiation in the cbk1 Δ/Δ mutant but is completely absent in the cbk1 Δ/Δ ssd1 Δ/Δ double mutant. Deletion of SSD1 also increased Als3 expression and internalization of the cbk1 Δ/Δ mutant in the human embryonic kidney cell line HEK293T. Collectively, our results suggest that one of the functions of Cbk1 in the hyphal morphogenesis of C. albicans is to downregulate Nrg1 through Ssd1.

We investigated the effects of process parameters on the microstructure and compressive properties of reactive-sintered porous TiAl-based intermetallics. Different extrusion ratios were selected in order to change the as-extruded microstructure and thus obtain various types of porous structures (unidirectional and spherical pores) after reactive sintering. In addition, different environmental conditions, such as vacuum and air, were used during the reactive sintering stage. It was revealed that the compressive strength is influenced by the unidirectionalty of the pores. High unidirectionalty led to higher yield strength at room temparature and at 1073 K. The compressive properties of the porous TiAl intermetallics were also influenced by the environment where reactive sintering is carried out.

This paper has proposed a 2,500 MHz ∼ 2,570 MHz 0.13-㎛ CMOS RF front-end transmitter for LTE-Advanced systems. The proposed RF front-end transmitter is composed of a quadrature up-conversion mixer and a driver amplifier. The measurement results show the maximum output power level is +6 dBm and the suppression ratio for the image sideband and LO leakage are better than –40 dBc respectively. The fabricated chip consumes 36 mA from a 1.2 V supply voltage.

Heavy metal contamination from abandoned mine areas is a major threat for the environment. The study objec- tive was to categorize the most polluted mine areas among 44 mine sites at the four cities of Chungcheongbuk-do province in South Korea. Both water and soil samples were collected from the mine area. The pH of the water and soil ranged from 3.6 to 8.5 and from 4.1 to 9.1 respectively. A significant amount of arsenic (As), cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), zinc (Zn) and mercury (Hg) occurred in soil samples collected from the mine areas (0.2 to 42.4, 0.7 to 8.6, 10.7 to 430.2, 5.8 to 49.8, 2.1 to 122.8, 37.4 to 359.4 and 0.2 to 11.4 mg kg -1 respectively). The surrounding available waters also carried high contents of Cd, Cu, Pb and Zn, generally exceeding the fresh water acute and chronic criteria. Each mine site was ranked according to the Integrated Pollution Index (IPI). The normalized pollution index (PI n ) for water and soil, and the Survey Index (SI) were used to determine IPI. The highest polluted mine site exhibited an IPI value of 0.6394. IPI was introduced to prioritize the research sites for further precise investigation.

An isolate from holothurians was identified as an eicosapentaenoic acid (EPA)-producing bacterium KMG427, which is characterized by EPA synthesis efficiency, by thin layer and gas chromatographic analyses. The EPA production was maximized to more than 10% of the total fatty acids by incubation at 4o degrees C after cell proliferation at 20 degrees C. The isolated bacterium was categorized as Gramnegative, rod-shaped, aerobic, and motile with a single polar flagellum. According to phylogenetic analysis based on morphological and physiological specificities as an EPA-producing bacterium, the isolate KMG427 was found to belong to the genus Shewanella. The 16S rDNA of KMG427 was revealed to have 100% of sequence identity to that of S. hanedai CIP 103207T. Therefore, the isolate might be classified and identified as Shewanella sp. KMG427.

Background Endophytic fungi are known plant symbionts. They produce a variety of beneficial metabolites for plant growth and survival, as well as defend their hosts from attack of certain pathogens. Coastal dunes are nutrient deficient and offer harsh, saline environment for the existing flora and fauna. Endophytic fungi may play an important role in plant survival by enhancing nutrient uptake and producing growth-promoting metabolites such as gibberellins and auxins. We screened roots of Ixeris repenes (L.) A. Gray, a common dune plant, for the isolation of gibberellin secreting endophytic fungi. Results We isolated 15 endophytic fungi from the roots of Ixeris repenes and screened them for growth promoting secondary metabolites. The fungal isolate IR-3-3 gave maximum plant growth when applied to waito-c rice and Atriplex gemelinii seedlings. Analysis of the culture filtrate of IR-3-3 showed the presence of physiologically active gibberellins, GA1, GA3, GA4 and GA7 (1.95 ng/ml, 3.83 ng/ml, 6.03 ng/ml and 2.35 ng/ml, respectively) along with other physiologically inactive GA5, GA9, GA12, GA15, GA19, GA20 and, GA24. The plant growth promotion and gibberellin producing capacity of IR-3-3 was much higher than the wild type Gibberella fujikuroi, which was taken as control during present study. GA5, a precursor of bioactive GA3 was reported for the first time in fungi. The fungal isolate IR-3-3 was identified as a new strain of Penicillium citrinum (named as P. citrinum KACC43900) through phylogenetic analysis of 18S rDNA sequence. Conclusion Isolation of new strain of Penicillium citrinum from the sand dune flora is interesting as information on the presence of Pencillium species in coastal sand dunes is limited. The plant growth promoting ability of this fungal strain may help in conservation and revegetation of the rapidly eroding sand dune flora. Penicillium citrinum is already known for producing mycotoxin citrinin and cellulose digesting enzymes like cellulase and endoglucanase, as well as xylulase. Gibberellins producing ability of this fungus and the discovery about the presence of GA5 will open new aspects of research and investigations.

An efficient corner matching algorithm is developed to minimize the amount of calculation. To reduce the amount of calculation, all available information from a corner detector is used to generate the model. This information has uncertainties due to discretization noise and geometric distortion, and this is represented by fuzzy rule base which can represent and handle the uncertainties. From fuzzy inference procedure, a matched segment list is extracted, and resulted segment list is used to calculate the transformation between object of model and scene. An auto-tuning scheme of the fuzzy rule base is developed to find out the uncertainties of features from recognized results automatically. To show the effectiveness of the developed algorithm, experiments are conducted for synthetic images and images of real electronic components.