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Background: Patellar tendinopathy is a common cause of limitations in daily life activities in young and/or active people. The patellar tendon consists of a complex of collagen fibers; therefore, collagen could be used as a scaffold in the treatment of patellar tendinopathy. Purpose: To evaluate the healing capacity of injected atelocollagen as a treatment scaffold for patellar tendon defect and, hence, its potential for the treatment of patellar tendinopathy. Study Design: Controlled laboratory study. Methods: After receiving a full-thickness patellar tendon defect, 24 New Zealand White rabbits were divided into a control group (without treatment) and an experimental group that received an atelocollagen injection into the defect. Six rabbits from each group were subsequently used for either histologic scoring or biomechanical testing. The Mann-Whitney U test was used to compare histologic evaluation scores and load to failure between the 2 groups. Statistical significance was set at P < .05. Results: The experimental group showed excellent repair of the damaged patellar tendon and good remodeling of the defective area. In contrast, the control group showed defective healing with loose, irregular matrix fibers and adipose tissue formation. A statistically significant difference was found between the 2 groups in both histologic scores and biomechanical tests at postoperative week 12. Conclusion: Injection of atelocollagen significantly improved the regeneration of damaged patellar tendons. Clinical Relevance: Atelocollagen gel injections could be used to treat patellar tendinopathy in outpatient clinic settings.

IntroductionThis study was conducted to investigate changes and new trends over the past 6 years by analyzing the current status of precocious puberty (PP) treatment and treatment costs in Korea between 2016 and 2021.Materials and methodsAnnual and monthly number of patients diagnosed with PP from 2016 to 2021 were reviewed using the data from Healthcare Bigdata Hub. Annual medical insurance expenses for the treatment of PP were also reviewed. The data were compared by the gender of the patients.ResultsThe number of patients diagnosed with PP rose from 86,352 in 2016 to 166,645 in 2021, while medical expenses rose from KRW 64,111,689,000 in 2016 to KRW 134,642,100,000 in 2021. The percentage of male PP patients increased from 9.21% in 2016 to 19.55% in 2021.ConclusionIncreasing numbers of Korean patients diagnosed with PP. Consistent with the situation in other countries, the rapid increase in the number of cases since April 2020 appears to be a result of the COVID-19 pandemic. In Korea, this is considered a nationwide phenomenon. Also on the rise is the incidence of PP in males, which appears to be due to an increased awareness of the phenomenon. Further investigations are required to determine the possible causes in increasing prevalence of PP.

Envelope tracking (ET) is a key technology improving efficiency of RF power amplifiers (PAs) and battery lifetime in mobile handsets. It has been commercialized since 4G LTE era, and is also being employed in 5G NR handsets. A supply modulator (SM) is a circuit generating power supplies of RF PAs for ET and average power tracking (APT) operations. Currently, the maximum channel BW and supported ET BW of 5G NR handset is 100MHz [1]–[4]. In a short time, over 100MHz BW will be necessary to support intra-band contiguous carrier aggregation cases of n77C/n78C/n79C in 3GPP standard [5]. The required instantaneous maximum output power of SM is about 10W which is calculated by the following parameters: 26dBm output power by power class 2 (PC2), 2dB loss of RF front-end module (FEM) due to complex operating band combinations (EN-DC for non-standalone mode, NE-DC, 2CA/3CA), 6dB higher instantaneous power due to peak-to-average power ratio (PAPR) at 1 resource block (RB), 1dB margin, and poor PA efficiency of around 33% (worst example) due to high carrier frequency of 5GHz at n79 band. The poor PA efficiency can be relaxed by high voltage PA design beyond 5V. In [1], a supply modulator with boosted output larger than battery voltage $(V_{BAT})$ is proposed, and the designed PA with 30% higher voltage shows 10% higher efficiency and broader BW owing to low impedance transformation ratio from $50 \Omega$ and small parasitic output capacitance of power cell. The challenge is how to design a supply modulator for 5G NR that can achieve both wide ET BW and high output voltage/power capability, while satisfying high efficiency, low receiver-band noise, short transition time, and multi-mode/standard operation.

Background This study aimed at determining the effect of the herbal mixture estrogen inhibition formula (EIF) and its possible mechanisms by precocious puberty animal models and network pharmacology-based analysis. Methods Precocious puberty animal models were established by a single injection of 300 μg danazol, then female rats were administered EIF, vaginal openings were monitored, uterus and pituitary indices were determined. The levels of ALP, E2, LH, and FSH were measured using ELISA kits. Real-time PCR was performed to evaluate the mRNA expression of GnRH, UNC5C, and netrin-1 in hypothalamic tissues. We applied network pharmacological analysis to predict potential targets and pathways of EIF. Results EIF delayed danazol-induced early vaginal opening. In the onset model, EIF reduced the increased levels of serum ALP, E2, LH, and FSH; as well as mRNA expressions of GnRH, Netrin-1, and UNC5C. Moreover, long-term administration of EIF not only diminished all impaired factors but also had no effect on the normal development of the animals. The gene set enrichment analysis showed that the targets of EIF are mainly associated with the GnRH signaling and ovarian steroidogenesis pathways. Conclusion EIF could be used in preclinical research for the treatment of precocious puberty by the inhibition of HPGA pre-maturation.

Patients who commit self-wrist cutting injuries (SWCIs) are a heterogeneous group composed of patients with non-suicidal self-injury (NSSI) and suicide attempt (SA). The purpose of this study was to compare the demographic features and wound characteristics of patients with NSSI and SA. A retrospective review of 300 patients who visited the emergency department (ED) for treatment of SWCIs between January 2011 and December 2015 was performed. Data collected from the electronic medical records included age, sex, the reason for SWCIs, presence of suicidal ideation, concomitant intoxication with alcohol or drugs, past psychiatric history, whether or not the patient received psychiatric counseling at the ED, the principal psychiatric diagnosis, the number and severity of external wounds, and subsequent follow-up at the psychiatric or hand surgery outpatient department (OPD). The patients were divided into the NSSI and SA groups according to the presence of suicidal ideation and other variables were compared between the two groups. There were 138 NSSI patients and 162 SA patients. The NSSI group was younger (33.9 years vs 40.9 years, P

In recent years, buck-boost converters have been widely utilized for battery-powered mobile systems such as RF power amplifiers, battery chargers, and LED drivers. However, in a wide battery voltage range, they face challenges including dynamic voltage scaling (DVS), wide load current range, and dynamic line/load transients while ensuring reliability for an industrial usage. To resolve these issues, the conventional buck-boost (CBB) converter should overcome the characteristic of discontinuity in the output transfer current (OTC) which causes degradation of loop dynamics and transient response. Several past works with continuous OTC have been proposed to resolve these problems, but their voltage conversion ratios are limited [1], [2]. Moreover, in [3], [4], a high-voltage (HV) process, which necessitates large active area and incurs high fabrication cost, is required to withstand voltage stresses over 10V (2×V IN ) applied across power switches. To overcome the above challenges, this paper proposes a voltage-tolerant three-level buck-boost (TLBB) converter. The TLBB has continuous OTC and uses only normal 5V CMOS devices for its switches. In addition, a voltage-tolerant dual channel-interleaved three-level buck-boost (DTLBB) converter is suggested for applications [5] requiring a wide range of load current and high conversion ratio while supporting fast DVS transition.

Background. Precocious puberty is a common endocrine disease in children. Inappropriate activation of hypothalamic–pituitary–gonadal axis leads to the development of secondary sexual characteristics at an earlier age than normal children and causes short stature in adulthood. Objectives. The aim of this study is to evaluate the preventive effects of a herbal formulation containing a mixture of Coicis Semen and Artemisia capillaris (hEIF extract) on precocious puberty. Methods. The preventive effect of hEIF extract on precocious puberty in rats was evaluated by measuring blood component after 3 weeks of treatment via oral administration. Network pharmacological analyses were performed to predict the bioactive components of hEIF extract. Results. In vivo studies showed that hEIF extract significantly reduced follicle stimulating hormone (FSH) levels. After treatment with 200 mg/kg of hEIF extract, the FSH level was 5.33±1.10 ng/mL, whereas the FSH level in the vehicle group was 46.73±0.80 ng/mL. Moreover, the use of hEIF extract did not stimulate body growth and bone accretion in rats. The network pharmacological analysis led to the identification of multiple targets of hEIF extract related to lipolysis and the female sex hormone-related pathways. Conclusion. hEIF extract can be used as an FSH inhibitor for the treatment of precocious puberty.

Background/aims This study analyzed the risk factors for technique survival in dialysis patients and compared technique survival rates between hemodialysis (HD) and peritoneal dialysis (PD) in a prospective cohort of Korean patients. Methods A total of 1,042 patients undergoing dialysis from September 2008 to June 2011 were analyzed. The dialysis modality was defined as that used 90 days after commencing dialysis. Technique survival was compared between the two dialysis modalities, and the predictive risk factors were evaluated. Results The dialysis modality was an independent risk factor predictive of technique survival. PD had a higher risk for technique failure than HD (hazard ratio [HR], 10.8; 95% confidence interval [CI], 1.9 to 62.0; p = 0.008) during a median follow-up of 11.0 months. In the PD group, a high body mass index (BMI) was an independent risk factor for technique failure (HR, 1.3; 95% CI, 1.0 to 1.8; p = 0.036). Peritonitis was the most common cause of PD technique failure. The difference in technique survival between PD and HD was more prominent in diabetic patients with a good nutritional status and in non-diabetic patients with a poor nutritional status. Conclusions In a prospective cohort of Korean patients with end-stage renal disease, PD was associated with a higher risk of technique failure than HD. Diabetic patients with a good nutritional status and non-diabetic patients with a poor nutritional status, as well as patients with a higher BMI, had an inferior technique survival rate with PD compared to HD.

Pinewood nematode (PWN: Bursaphelenchus xylophilus ) is known to kill pine tree species that are indigenous to countrieswhere the pest was inadvertently imported, but some cultures from the extraction of dead pines do not damage trees. Experiments wer econducted to examine the effect of pre-inoculation of these low-pathogenic pinewood nematode on resistance of pine trees agains t the pest species. The pre-inoculated pine saplings showed induced resistance which lasted for a year, and repeated inoculation of these low-pathogenic nematodes enhanced tree resistance. All nematode samples extracted from dying or dead pines that had been killed notmore than three months before the extraction were pathogenic, and most of those extracted from pines that had been killed 2-3 years before were low-pathogenic. When inoculated in pine saplings, number of low-pathogenic nematodes settled, as studied two days af ter inoculation, was not different from that of pathogenic ones. However, as studied after 30 days of inoculation, rate of reproduction in low-pathogenic nematodes was far lower than that of pathogenic nematodes. The rate of reproduction of several nematode isolates growing on fungal mat media of Botrytis cinerea varied, but three of four low-pathogenic isolates showed same level of reproduction rate sas pathogenic ones.Key words: Pinewood nematode, Bursaphelenchus xylophilus, Low-pathogenic, Pre-inoculation, Induced resistance초 록: 소나무재선충은 현재까지 도입된 국가의 토착수종인 소나무류를 모두 치사시키는 것으로 알려져 있으나 , 고사목으로부터 추출․배양된 계통 중에는 소나무에 피해를 주지 않는 계통이 존재한다. 이러한 저병원성 계통 선충의 사전접종이 고병원성 소나무재선충에 대한 소나무의 저항성에 미치는 영향을 조사하기 위하여 연구가 수행되었다. 치수에 저병원성 소나무재선충을 선접종한 결과, 선접종에 의하여 소나무재선충에 대한 저항력이 유도되었다. 그 유도저항성은 1년 후까지 유지되었으며, 저병원성 선충의 반복 감염은 보다 저항성 유도 효과가 큰 것으로 나타났다 . 소나무재선충에 의하여 고사한 후 경과기간이 3개월 이하인 피해목 및 피해진행목에서 분리된 선충은 모두 고병원성이었으며, 고사 후 2-3년이 경과한 벌채목에서 분리된 선충 5계통 중 4계통은 저병원성이었다. 저병원성 선충이 소나무 치수에 인공접종 되었을 때 초기 정착률은 고병원성 선충과 차이가 없었으나, 접종 30일 후에 수목내의 부위별 개체수를 조사한바 저병원성 선충의 증식률은 고병원성보다 현저히 낮았다 . 저병원성 선충의 잿빛곰팡이병 균사배지에서의 선충증식 속도는 계통에 따라 차이가 있었으며, 증식속도가 빠른 계통은 대체로 고병원성 선충의 증식속도와 차이가 없었다.검색어: 소나무재선충, 저병원성, 선접종, 유도저항성*Corresponding author: pscpine@hanmail.netReceived February 25 2014; Revised March 10 2014Accepted March 31 2014

Objectives: The objective of this study is to review the diagnostic methods of neurologic symptoms by non-organic causes. Methods: We experienced a case of a motor and sensory disturbance patient without abnormal findings in the diagnostic tests. Using this process, we became aware that it is important to remember some of the methods when treating patients who are suspicious of neurologic symptoms by non-organic causes. Results: First, we should perform a variety of diagnostic tests to exclude the organic causes. Second, we should persistently observe a consistency of the patient`s symptoms and attitude. Finally, we should perform a neurological examination in order to acquire the objective physical findings. Conclusions: Because there are limitations in the methods above, we have to be aware of making a mistake regarding the disability by organic causes as that by non-organic causes.

Unilateral sagittal split fracture (USSF) of the C1 lateral mass (LM) has been recently recognized as a rare variant of C1 atlas fracture. To date, there has been no study to investigate whether radiologic criteria can be applied to determine the presence or absence of transverse atlantal ligament (TAL) injury in USSF of the C1 LM. Twenty six consecutive cases of USSF of the C1 LM were included in this study. According to Dickman classification, 16 cases were TAL injury, and 10 cases were TAL intact. Radiologic parameters were measured and compared between the 2 groups. Total LM displacement (LMD) of the 2 sides (5.9 ± 2.0 mm vs 1.2 ± 2.0 mm), unilateral LMD of the fracture side (4.3 ± 1.2 mm vs 1.0 ± 1.1 mm), atlanto-dental interval (ADI) (2.0 ± 0.9 mm vs 1.5 ± 0.4 mm), and fracture gap (6.9 ± 2.7 mm vs 2.1 ± 1.1 mm) were statistically higher in the TAL injury group than the TAL intact group. However, basion-dental interval, clivus canal angle, and atlanto-occipital joint axis angle were not different between the 2 groups. Total LMD and unilateral LMD positively correlated with ADI and fracture gap. The incidence of fracture gap larger than 7 mm was statistically higher in the TAL injury group than the TAL intact group (81% vs 30%). In conclusion, total LMD > 5.9 mm or unilateral LMD > 4.3 mm suggests the presence of TAL injury in USSF of the C1 LM. The possibility of diagnostic error for TAL injury can be further reduced in USSF of the C1 LM by considering the fracture gap larger than 7 mm.

A set of experiments were conducted to determine the zero temperature and total effective temperature for the summer diapause and post-diapause development of Matsucoccus thunbergianae Miller et Park (Hemiptera: Margarodidae) which infests the Japanese black pine, Pinus thunbergii. The diapausing first instar nymphs were kept in cool storage during three separate times, each starting from May 4th, June 19th, and August 15th of 2002. Cool storage temperatures were 2.5, 5.0, 7.5, 10.0, 12.5 and . The nymphs were chilled for 10, 20, 30 or 40 days in the first two sets of experiments. In the third experiment, nymphs were chilled for 3, 6, 9 or 12 days. Molting into the second instar nymphs was examined every 10 days, starting at 20 days after taken out from the cool storage. Optimum temperature range of the diapause development was between 7.5 and , where diapause development was completed in 40, 20, and 6 days by the insects chilled from May 4th, June 19th and August 15th, respectively. Comparing the three sets of experiments with different chilling periods, zero temperature for diapause development was calculated as . Effective temperature for diapause development was 964 degree days, and it was estimated that nymphs completed their diapause development by September 8th in nature. Under natural temperature conditions >50% eclosion into the second instar occurred on November 9th. Zero temperature for post-diapause development was , and total effective temperature for post-diapause development until the molt into the second instar was 391 degree days.

The doctor blade is equipped in a toner cartridge and is a device to maintain the uniform thickness of a toner by controlling the pressure on the developing roller. The contact pressure between the developing roller and the doctor blade is one of the significant factors for image quality and durability of toner cartridge. The purpose of this study is to develop approximation model in order to minimize the time and cost which are needed much required in making optimal design of the doctor blade. Central composite design was used for the design of experiment and response surface design was used for approximation. The data for contact pressure were acquired through finite element analysis and data of image density and toner weight were acquired through experiment. The approximation model developed in this study has presented very high fitness.

This paper proposes an oppositely coupled varactor pair and reports the measured results for applying to a test digitally controlled oscillator (DCO). The pair exploits the differences between the accumulation region capacitance and inversion region capacitance of pMOS varactors. The novel varactor pairs provide much smaller switchable capacitances than those of other approaches, and hence, the test DCO for verifying the property of the pair achieves the high-frequency resolution. The pairs and test DCO are implemented in a 0.18-μm CMOS process. The switchable discrete capacitance of 32 aF is obtained by using the novel varactor pairs, and the test DCO has a frequency resolution of about 110 kHz at 5.8 GHz. Furthermore, ΔC of 4-aF and 14-kHz frequency resolution can be obtained through the dithering processes. The test DCO achieves a low phase noise of -117.6 dBc/Hz at 1-MHz offset from 5.8 GHz.

I show the ratio of the short-term moving average to the long-term moving average (moving average ratio, MAR) has significant predictive power for future returns. The MAR combined with nearness to the 52-week high explains most of the intermediate-term momentum profits. This suggests that an anchoring bias, in which investors use moving averages or the 52-week high as reference points for estimating fundamental values, is the primary source of momentum effects. Momentum caused by the anchoring bias do not disappear in the long-run even when there are return reversals, confirming that intermediate-term momentum and long-term reversals are separate phenomena.

South Korean industrial conglomerates (chaebols) are discussed in the context of value-based management (VBM). Recent economics and finance literature on the diversion of corporate resources from the firm to the controlling shareholders (tunneling), for which chaebols are notoriously known, is discussed. Chaebols have engaged in empire building and expropriation of minority shareholders, distorting the process of efficient resource allocation in South Korea, and became the root cause of the 1997 financial crisis. We argue that the 1997 crisis should be viewed as a consequence of chaebols’ systematic deviation from the guiding principles of VBM. We use tunneling within chaebols as an example of the need to directly address prohibition of the expropriation of minority shareholders as a primary postulate of VBM. We argue that VBM should require that the value generated by the firm not be expropriated from minorities, or any stakeholders, by dominant shareholders. We also examine moral and ethical considerations and present explanations as to why the unethical practice of tunneling has been tolerated by the South Korean public. We show that public opinion on tunneling is changing and that the treatment of minority shareholders by chaebols’ controlling families is becoming increasingly unacceptable to South Koreans.

A linear induction motor (LIM) with a cage-type secondary has contact resistances between side-bars and secondary conductors due to its own manufacturing process of welding. The finite-element analysis considering the equivalent circuit of the secondary winding is carried out to present the effect of the contact resistance in the LIM. As a result, thrust, normal force, the primary phase current, and the secondary conductor currents of the motor are analyzed for the various contact resistances.

Most single-phase brushless DC (BLDC) motors have unequal air gaps to eliminate the dead point where the developed torque value is zero. These unequal air gaps deteriorate the motor characteristics in cogging torque. Thus in this paper a new topology of the unequal air gaps is proposed to solve this problem. As a result, it is proved by the finite element analysis and experimental results that the proposed air gap topology is very effective in reducing the cogging torque.

In this paper, we discuss the analysis for the dynamic characteristics of a single-sided linear induction motor (SLIM) having the joints in the secondary conductor and the back-iron. The time-stepping finite element method and the moving mesh techniques are used for the simulation. The gradients of the electric scalar potential in the jointed secondary conductors and back-irons are defined for the eddy current analysis. The simulation results show that the junction between the secondary conductors creates a discontinuity of the eddy current and causes fluctuations of the thrust and the normal force.

This paper presents the finite element analysis for the dynamic characteristics of an inverter-fed permanent magnet linear synchronous motor (PMLSM) having the conductive sheet secondary. The time-stepping finite element method and the moving mesh technique are used for the simulation. The eddy currents in the secondary aluminum sheet and solid back-iron are taken into account in the electromagnetic field analysis.

The real brushless DC motor has different permanent magnet pole magnetization levels due to the influence of the magnetizer geometry. Therefore, this paper discusses the influence of change in the magnetic parameter on brushless DC motor performances. As a result, the unbalanced magnetic force acting on the rotor, cogging torque and torque ripple are examined for spindle motor with unsymmetric magnetization distribution.

This paper describes the effect of eddy currents generated in the rotor steel shell of an exterior-rotor type permanent magnet brushless DC motor of which the rotor is revolving at a high speed. A two dimensional time-stepped finite element method is used to analyze the electromagnetic field and compute motor performance. The conductivity of the rotor steel shell is modified to consider the transverse edge effect. As a result, the effect of eddy currents is shown by comparing the analysis results between when the proposed method is used and when the method it is not.

This paper discusses the phenomena of the axially nonuniform distribution of magnetic flux densities and losses in a three-phase squirrel cage induction motor of which the rotor bars are skewed. A 2-D complex finite element method, taking account of the effects of the skewed rotor bars, is utilized for the analysis of characteristics such as copper and iron losses and the loss distributions are examined. The summing up values of nonuniform losses resulted from the finite element analysis are compared with measurements.

Sex pheromone-associated behavior of two tortricid moths in New Zealand, Planotortrix notophaea and P. octo , was studied in a laboratory. Most males of both species changed their antennal posture responding to the change from light to dark phase. Three antennal postures in both sexes were designated by dorsal view: antennae in resting position, those extended less than 80° from body axis, and those extended more than 80° from the body axis. In P. notophaea , antennal posture of males appeared as an external indicator representing the physiological readiness for pheromone perception; males with antennae extended more than 80° from the body axis responded better than those in resting position. Bioassays with medicine droppers indicated that threshold concentrations for male response to crude female pheromone extract were 3 × 10 −3 female equivalents (FE) and 3 × 10 −7 FE in P. notophaea and P. octo , respectively. In P. octo , threshold concentrations for male response to known pheromone compounds, (Z)-8-tetradecenyl acetate and tetradecyl acetate, were 10 fg and 100 fg, respectively. Female calling appeared continuous rather than being pulsed. In P. notophaea , stronger male responses were elicited toward females with antennae extended more than 80° from the body axis than those in resting position.

This paper presents a method to analyze radial force densities acting on each stator tooth of an induction motor with skewed slots. A two-dimensional finite element method is used for electromagnetic field analysis of an induction motor, and skew effects are considered by coupling several disks cut by planes perpendicular to the shaft. Radial force densities as a source of vibration are calculated along the surface elements of each stator tooth and its time harmonics are examined by discrete Fourier decomposition.

The optimization of the design variables of a single-sided linear induction motor (SLIM) using the finite-element method (FEM) and the sequential unconstrained minimization technique (SUMT) is presented. Thrust is taken as an objective function in order to maximize thrust under a constant current drive, and seven independent design variables and nine constraints are chosen. As a result, pole pitch/airgap and pole pitch/aluminum depth for the best design are determined. Thrust is increased by 30% under a constant current of 12 A, so that the input current can be reduced to 10.5 A for necessary starting thrust because thrust is proportional to I/sup 2/. >

The predictive power of past returns for January reversal is compared with that of the nearness of current prices to the 52-week high. When compared jointly, past returns lose their forecasting power for January returns and the nearness of current prices to the 52-week high assumes the dominant role in explaining the January reversal. This suggests that tax-loss selling is not the primary factor explaining the January effect. A behavioral explanation consistent with the window-dressing argument is proposed in that the 52-week high acts as an “anchor,” a highly visible reference price to fund holders, increasing fund managers’ incentives to window-dress by temporarily adding (removing) stocks that are perceived by fund holders as good (bad) investments, based on the nearness of these stocks’ current prices to the 52-week high.

Attracting ferromagnetic forces between magnet and reaction rail provide the supporting force in Electromagnetic Suspension. Miniature maglev using permanent magnets and electromagnets is based on the idea to generate the nominal magnetic force by permanent magnets and superimpose the variable magnetic field required for stabilization by currents flowing through control windings in electromagnets. Permanent magnets with a high energy density have lower power losses with regard to supporting force and magnet weight. So the advantage of the maglev using electromagnets and permanent magnets is partially reduced by the power required to feed the remaining onboard supply system so that the overall onboard power is diminished as compared to that of the electromagnet. In this paper we proposed the how to design and control the miniature maglev and confirmed the feasibility of the levitation system using electromagnets and permanent magnets through the manufacturing the miniature maglev.