543 research outputs found

    Ultra-low Power Circuits for Internet of Things (IOT)

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    Miniaturized sensor nodes offer an unprecedented opportunity for the semiconductor industry which led to a rapid development of the application space: the Internet of Things (IoT). IoT is a global infrastructure that interconnects physical and virtual things which have the potential to dramatically improve people's daily lives. One of key aspect that makes IoT special is that the internet is expanding into places that has been ever reachable as device form factor continue to decreases. Extremely small sensors can be placed on plants, animals, humans, and geologic features, and connected to the Internet. Several challenges, however, exist that could possibly slow the development of IoT. In this thesis, several circuit techniques as well as system level optimizations to meet the challenging power/energy requirement for the IoT design space are described. First, a fully-integrated temperature sensor for battery-operated, ultra-low power microsystems is presented. Sensor operation is based on temperature independent/dependent current sources that are used with oscillators and counters to generate a digital temperature code. Second, an ultra-low power oscillator designed for wake-up timers in compact wireless sensors is presented. The proposed topology separates the continuous comparator from the oscillation path and activates it only for short period when it is required. As a result, both low power tracking and generation of precise wake-up signal is made possible. Third, an 8-bit sub-ranging SAR ADC for biomedical applications is discussed that takes an advantage of signal characteristics. ADC uses a moving window and stores the previous MSBs voltage value on a series capacitor to achieve energy saving compared to a conventional approach while maintaining its accuracy. Finally, an ultra-low power acoustic sensing and object recognition microsystem that uses frequency domain feature extraction and classification is presented. By introducing ultra-low 8-bit SAR-ADC with 50fF input capacitance, power consumption of the frontend amplifier has been reduced to single digit nW-level. Also, serialized discrete Fourier transform (DFT) feature extraction is proposed in a digital back-end, replacing a high-power/area-consuming conventional FFT.PHDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/137157/1/seojeong_1.pd

    Does robot-assisted laparoscopic radical prostatectomy enable to obtain adequate oncological and functional outcomes during the learning curve? From the Korean experience

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    To estimate the short-term results of robot-assisted laparoscopic radical prostatectomy (RALRP) during the learning curve, in terms of surgical, oncological and functional outcomes, we conducted a prospective survey on RALRP. From July 2007, a single surgeon performed 63 robotic prostatectomies using the same operative technique. Perioperative data, including pathological and early functional results of the patient, were collected prospectively and analyzed. Along with the accumulation of the cases, the total operative time, setup time, console time and blood loss were significantly decreased. No major complication was present in any patient. Transfusion was needed in six patients; all of them were within the initial 15 cases. The positive surgical margin rate was 9.8% (5/51) in pT2 disease. The most frequent location of positive margin in this stage was the lateral aspect (60%), but in pT3 disease multiple margins were the most frequent (41.7%). Overall, 53 (84.1%) patients had totally continent status and the median time to continence was 6.56 weeks. Among 17 patients who maintained preoperative sexual activity ( Sexual Health Inventory for Men \u3e = 17), stage below pT2, followed up for \u3e 6 months with minimally one side of neurovascular bundle preservation procedure, 12 (70.6%) were capable of intercourse postoperatively, and the mean time for sexual intercourse after operation was 5.7 months. In this series, robotic prostatectomy was a feasible and reproducible technique, with a short learning curve and low perioperative complication rate. Even during the initial phase of the learning curve, satisfactory results were obtained with regard to functional and oncological outcome

    Retroperitoneal laparoscopic ureterolithotomy for upper ureter stones

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    We evaluated the role of retroperitoneal laparoscopic ureterolithotomy (RPLU) for upper ureter stones. Between February 1998 and July 2004, 12 patients (10 men and 2 women) underwent RPLU for upper ureter stones (mean size 18.1 mm, range 10-25). RPLU was carried out in 5 patients as a salvage treatment after failed shock wave lithotripsy (SWL) (3) and both of failed SWL and ureteroscopy (URS) (2), and in 7 patients as primary treatment for large impacted stones. Total 6 of 12 cases were converted to open surgery. The reason of open conversion was failure of locating ureter due to severe adhesion in 5 cases and vascular injury in 1 case. In 6 successful cases, mean operation time, mean estimated blood loss, and mean postoperative hospital stay were respectively 109 min (90-120 min), 50 mL (10-100 mL), 4.6 days (2-7 days). There was no serious postoperative complication except for one patient who showed delayed urinary leakage but was cured with conservative management. Our experience suggested that RPLU was not easy to perform simply because it was indicated mainly in ureter stones with severe adhesion or after failed SWL and/or URS. Nevertheless, it can be considered as a primary procedure before open ureterolithotomy

    Breeding of Sweet Shinhong pepper by Marker-assisted backcrossing (MABC)

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    Capsinoids is unique compound of pepper, which have similar biological effect to apsaicinoids like anticancer and anti-obesity. However, because the characteristic of capsinoids is non-pungency contrary to capsaicinoids, it has been studied to investigate genetic factor related to biosynthesis of capsinoids and to breed pepper variety producing capsinoids. Two pathway are known to be involved in capsaicinoids synthesis, phenylpropanoid and valine pathway. Capsinoids biosynthesis pathway is common to capsaicinoids, but putative-aminotransferase (pAMT) gene mutation in phenylpropanoid pathway cause capsinoids production instead of capsaicinoids. SNU11-001 which have pAMT gene mutation produce high level of capsinoids and Shinhong is Korean chili pepper. In previous research, pAMT mutation in SNU11-001 have been introgressed to Shinhong to breed novel Shinhong pepper containing high contents of capsinoids by Marker-Assisted Backcrossing (MABC) method. Recessive homozygous pAMT allele was selected by genotyping with KASP marker for foreground selection and 8 to 10 plants which recovered by Shinhong genome highly were selected by Fluidigm high-throughput genotyping analysis. Shinhong C × SNU11-001 (SSHC) BC2F1-40 was selected by MABC with 198 SNP markers and recovery rate was 96.3%. In this study, MABC of SNU11-001 × Shinhong C (SSHC) BC3F1 and SNU11-001 × Shinhong B (SSHB) BC2F1 was proceeded. 202 and 102 markers were used for background selection, respectively. 10 SSHC BC3F1 progenies showed the highest recovery rate, 99.5%. The range of recovery rate in SSHB BC2F1 was 89.6 to 96.7%. SSHC BC2F2 was from self-crossing of SSHC BC2F1-40 and several pamt/pamt plants were selected. We will develop SSHB BC2F2 line which have pAMT mutation allele and high recovery rate of Shinhong B. This SSHB BC2F2 progeny will have cytoplasmic male sterility by being crossed with Shinhong A. Finally we will be able to breed sweet Shinhong F1 hybrid containing high level of capsinoids.OAIID:RECH_ACHV_DSTSH_NO:A201625343RECH_ACHV_FG:RR00200003ADJUST_YN:EMP_ID:A076900CITE_RATE:FILENAME:20161027_원예학회 포스터_장시영(ARC2-1).pdfDEPT_NM:식물생산과학부EMAIL:[email protected]_YN:FILEURL:https://srnd.snu.ac.kr/eXrepEIR/fws/file/e1d431a8-f997-43db-85e2-5ccb8e76020e/linkCONFIRM:

    Evaluation of the efficacy of ivermectin against Theileria orientalis infection in grazing cattle

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    Background Raising cattle on pastures is known to be beneficial for animal welfare and cost reduction. However, grazing is associated with the risk of contracting tick-borne diseases, such as theileriosis. Here, the efficacy of ivermectin against these diseases and associated clinical symptoms were evaluated. Results A total of 68 cattle from a grazing cattle farm were selected and divided into two groups: the control group (17 cattle) with no preventive treatment and the ivermectin-treated group (51 cattle) in which cattle were treated with pour-on ivermectin prior to grazing. The infection rates of Theileria orientalis and the red blood cell (RBC) profile (e.g., RBC count, hematocrit value, and hemoglobin concentration) were compared in the spring (before grazing) and summer (during grazing) between the two groups. Based on PCR amplification of the major piroplasm surface protein (MPSP) gene, 12 cattle were positive for T. orientalis infection. Phylogenetic analysis revealed that the isolates identified in this study consisted of three MPSP types (1, 2, and 7). The T. orientalis infection rate in the control group during grazing was 3-fold higher than that in the ivermectin-treated group. Moreover, differences in RBC parameters during grazing were greater in the control group than in the ivermectin-treated group. In particular, the hematocrit value was significantly reduced in the control group. Conclusions The results of this study demonstrated that ivermectin had protective effects against T. orientalis infection and RBC hemolysis in grazing cattle.This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF2017R1A2B2005685). This research was partially supported by Technology Development Program (Project No. 1116043–1) for Bio-industry, Ministry for Agriculture, Food and Rural Affairs, Republic of Korea. The funders had no role in the study design, data collection and analysis, interpretation of results, writing of the report, decision to submit the paper for publication

    Efficacy of prolonged entecavir monotherapy in treatment-naïve chronic hepatitis B patients exhibiting a partial virologic response to entecavir

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    Background/AimsThe optimal management of patients exhibiting a partial virologic response (PVR) to entecavir (ETV) has not been determined. The aim of this study was to determine the long-term efficacy of prolonged ETV monotherapy in treatment-naïve chronic hepatitis B (CHB) patients exhibiting a PVR to ETV therapy.MethodsThis study included 364 treatment-naïve CHB patients treated with ETV for ≥48 weeks and who received continuous ETV monotherapy for ≥96 weeks. PVR was defined as a decrease in serum hepatitis B virus (HBV) DNA of more than 2 log10 IU/mL from baseline but with detectable HBV DNA by real-time PCR assay at week 48.ResultsFifty-two of the 364 patients (14.3%) showed a PVR. Among them, 41 patients received continuous ETV monotherapy for ≥96 weeks (median duration 144 weeks, range 96-312 weeks), and 40 of these patients (95%) achieved a virologic response (VR, HBV DNA <20 IU/mL) during prolonged ETV monotherapy (median duration 78 weeks, range 60-288 weeks). The cumulative probabilities of a VR at weeks 96, 144, and 192 from treatment initiation were 78.0%, 92.7%, and 95.1%, respectively. The VR rate was 97.2% (35/36) in HBeAg-positive patients and 100% (5/5) in HBeAg-negative patients. In multivariate analysis, HBeAg positivity (odds ratio [OR], 9.231; 95% confidence interval [CI], 1.03-82.91; P=0.047) and a high baseline HBV DNA level (OR, 0.170; 95% CI, 0.08-0.37; P=0.000) were independently associated with a delayed virologic response. No patient developed genotypic resistance to ETV during follow-up.ConclusionsLong-term ETV monotherapy is effective for achieving a VR in treatment-naïve CHB patients exhibiting a PVR to ETV. HBeAg positivity and high baseline HBV DNA level were independently associated with a delayed virologic response
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