This study examined the subacute oral toxicity of Dendropanax morbiferus H.Lév leaves hot-water extracts (DMWE) using male and female Spargue-Dawley rats. Rats were orally administered the DMWE at dose levels of 0, 250, 500, 1,000, and 2,000 mg/kg body weight (BW) for four weeks. For experimental period, clinical signs and the number of deaths were examined, and feed intake and BW of all experimental animals were measured once a week for four weeks. At the end of the experiment, blood samples were collected from all rats, and all animals were euthanized and autopsies were performed to collect major organs. No dead animals were found during the experimental period. In addition, no differences were found between control and DMWE-treated groups in feed intakes, BW changes, organ weights, clinical signs, hematological parameters, and serum biochemical parameters. The results of this study provided evidence that oral administration of DMWE at the dose of 2,000 mg/kg BW is safe in rats and may not exert severe toxic effects.
목적 : 해마다 고령인구는 급격히 증가하고 있어 연령 증가에 따른 백내장 환자도 증가하고 있다. 대부분의 백 내장 수술은 원거리 중심으로 근거리에 대한 부분은 많은 정보가 없다. 다초점 인공수정체를 사용한 수술의 경우 시력 흐림등의 부작용이 존재하고 있어 백내장 수술 후 근거리 가입도에 대한 효과적인 처방이 필요한 실정이다.
방법 : 백내장 수술 전 ․후의 성인 21명 총 42안을 대상으로 굴절이상도, 교정시력, 가입도, 입체시력 등을 측 정하였다. 백내장 수술 후 굴절력이 안정되는 3달 후 검사를 진행하였다. 성별 및 굴절도에 따라 가입도 변화를 분석하였다.
결과 : 백내장 수술 후의 교정시력, 입체시력 및 가입도 모두 유의미하게 상승하였다. 남성이 여성보다 가입도 변화가 적은 것을 확인하였고 원시안에서 근시안보다 가입도 변화가 크게 나타나는 것을 확인하였다.
결론 : 백내장 수술 후에는 위조절에 의해 이론적인 가입도보다 낮은 가입도가 측정된다. 위조절이 나타나는 다양한 인자들을 고려하여 가입도 처방을 한다면 보다 나은 시생활을 영위할 수 있을 것으로 판단된다.
In this study, the acute toxicity of Dendropanax morbiferus H.Lév leaf hot-water extracts (DMWE) was examined in male and female ICR mice. Mice were orally administered the DMWE at dose levels of 0, 250, 500, 1,000 and 2,000 mg/kg body weight (BW) for single-dose toxicity test. There were no significant differences in change of BW between control and all DMWE treated-groups. In hematological and blood biochemical analysis, none of the parameters were affected by the DMWE. Similarly, there were no significant effects on markers for liver and kidney functions in all DMWE treated-groups. Since there were no adverse effects of the DMWE in single oral toxicity tests, even at the highest doses, it was concluded that the lethal dose 50 (LD50) of DMWE is estimated at > 2,000 mg/kg BW.
본 연구는 코팅 방법을 활용한 단결정 양극 소재 연구로서 Ni-rich계 다결정 양극 소재로 부터 단결정 양극 소재를 합 성하여 사이클 구동 시 양극 소재의 안정성을 향상시키고자 한다. 양극 소재에 LixCoO2와 LixSnO3 를 각각 코팅하여 이차입자 내부 혹은 외부에 코팅층이 형성된 양극 소재를 합성한 후 이를 소결하여 단결정 형성에 대한 영향을 비교 하였다. 입자 외부에 LixSnO3가 코팅되어 열처리 된 Ni0.8Co0.1Mn0.1O2(NCM811)의 경우 코팅 처리 없이 열처리된 양극 소재 보다 개선된 수명특성을 보였으나, 단결정화가 이뤄지지 않았다. 입자 내부에 LixCoO2 코팅층이 형성된 NCM811 을 열처리 한 결과 이차입자 내부에 형성된 Co 코팅층이 결정화되어 50회 사이클 후 기준 단결정 양극 소재의 방전용 량인 117.34 mAh·g-1 대비 129.11 mAh·g-1의 높은 방전용량을 나타내었고, 형상제어를 통해 이성적인 단결정화가 이뤄 졌다. 본 연구는 다결정체인 Ni-rich 양극소재의 단결정화에 대한 유요한 통찰력을 제공할 것으로 예상한다.
대부분의 모바일 AR 컨텐츠들은 모바일 디바이스의 기술적 한계로 인해 평면 탐지 후, 그 위에서만 구현되는 제한된 구조를 가지고 있다. 이러한 문제는 제한된 공간이 표현의 범위를 제한하기 때문에 모바일 AR의 확산 에 크게 저해가 될 수 있다. 한편 Unity의 AR Foundation이 제공하는 ‘Meshing’은 실제 오브젝트의 크기와 위 치에 알맞게 메시를 생성해주는데, 이를 활용한다면 모바일 AR 컨텐츠들은 평면에서 벗어나 더 넓은 현실 공 간에 구현될 수 있다. 하지만 ‘Meshing’은 모바일 기기의 센서가 닿지 못하는 부분에는 메시를 생성하지 않기 때문에 별도의 작업 없이 그대로 사용한다면 게임 오브젝트가 빠져나갈 수 있는 구멍이 생길 수 있다. 이 구 멍은 컨텐츠 구현에 있어서 치명적이기에 Hole-Filling 알고리즘을 사용하여 구멍을 메우고자 하는 연구가 있 었다. 하지만 기존 연구에서 사용하는 Hole-Finding 알고리즘은 특정 상황에서 외곽선과 구멍을 제대로 구별해 내지 못하는 문제가 있다. 이 문제는 일부 구멍은 메우지 못하고 외관선끼리 이어버려 컨텐츠에 치명적인 문 제를 야기한다. 본 논문에서는 Meshing이 제공하는 노말 벡터와 경계선들로 계산한 노말 벡터 간의 차이를 이 용해 구멍과 외곽선을 구분하는 방법을 제안한다. 이 방법을 적용한 결과, 이전 연구의 방법보다 좀 더 빠르 면서 구멍과 외곽선을 제대로 구별하는 모습을 확인하였다.
Tuberculosis is a potentially deadly infectious disease caused by the Mycobacterium tuberculosis (M. tuberculosis). Tuberculosis is diagnosed by proving the M. tuberculosis in sputum samples based on the results of acid-resistant staining, culture, and nucleic acid amplification tests. However, there is a report that the detection rate of M. tuberculosis is low in acid-resistant staining using tissue specimens. It has been suspected that the cause is a potential loss of acid resistance by the organic solvents used for tissue specimen preparation. Therefore, this study was pursued to find out if Gram staining and fluorescent staining in addition to acid-resistant staining would be helpful in diagnosing tuberculosis. We used four tissue (lung, small intestine, large intestine, and lymph node) samples with chronic granulomatous inflammation observed in HE staining and positive results in real-time PCR. These detection rates and staining properties were investigated through microscopic examination using the Ziehl-Neelsen, Gram, and Auramin rhodamine staining. In this studies, M. tuberculosis were observed by Ziehl-Neelsen, Gram, and Auramin rhodamine staining in all four samples. In the evaluation of clinical microbiology proficiency testing (CMPT), the Ziehl-Neelsen and Gram staining were the same result, but the Auramin rhodamine staining was relatively low. These data indicated that Gram staining is useful for detecting M. tuberculosis in formalin-fixed tissue specimens. Therefore, if the Ziehl-Neelsen and Gram staining are combined as the M. tuberculosis staining method in tissue specimens, a better direction may be provided for tuberculosis diagnosis.
Fermentation by Rhizopus spp. has been used as a traditional medicine for treating various inflammatory diseases. Allergic asthma is a chronic respiratory disease that is caused by an exaggerated immune response. This study was conducted to ascertain the anti-inflammatory effects of Rhizopus spp. fermentation extract (RU) on a mouse model of ovalbumin (OVA)-induced asthma. The animals were intraperitoneally injected OVA on day 1 and 7, followed by OVA intranasal inhalation on days 14 to 18. The animals were treated daily with RU (100 and 200 mg/kg) by oral gavage from day 18 to day 23. RU significantly decreased eosinophilia and the production of inflammatory cytokines and OVA specific immunoglobulin E in animals with asthma, along with reducing airway inflammation and mucus secretion in lung tissue. Histological changes in the lungs and levels of inflammatory mediators of allergic airway inflammation were evaluated. The regulatory effects of RU on type 2 helper T (Th2) cell activation were investigated. RU administration attenuated asthmatic changes such as inflammatory cell infiltration and mucus production, decreased the levels of Th2-related cytokines, and reduced Th2 cell activation. Administration of RU effectively reduced allergic responses in asthmatic mice, which is associated with regulating Th2 cell activation and differentiation. These results indicate that RU can attenuate the respiratory symptoms of asthma.
Malaysia’s decision to join and rectify the agreement showed that the country is serious about business, trade liberalisation and its support for a fair and transparent trade regime. Moreover, Malaysia is expected to earn approximately USD 200 million in exports, while RCEP will provide immense opportunities for trade and investments, enhanced connectivity, and deepening regional economic integration. This study aims to analyse the extent to which Malaysia’s participation in the RCEP can benefit the country’s growth and development. For this goal, a SWOT analysis will be carried out to assess the strength, weaknesses, opportunities and threats of joining RCEP, from Malaysia’s perspective. Findings suggest that Malaysia is indeed one of the main beneficiaries of the RCEP agreement in comparison to other ASEAN nations. However, much needs to be done by Malaysia to reap the benefits of the world’s largest trading bloc, while maintaining its national interests amidst a more liberal and open market setting.
Ammonia is considered a promising hydrogen carrier due to its high hydrogen density and liquefaction temperature. Considering that the energy efficiency generally decreases as chemical conversion is repeated, it is more efficient to directly use ammonia as a fuel for fuel cells. However, catalysts in direct ammonia fuel cells have the critical issues of sluggish ammonia oxidation reaction (AOR) rate and poisoning of reaction intermediates. In particular, the use of precious metal as cathodic catalysts has been limited due to ammonia crossover and poisoning. In this study, we introduce Fe-based single-atom catalysts with selective activity for the oxygen reduction reaction (ORR) even in the presence of ammonia. As the Fe content increased, the single-atom structure of the catalysts changed into Fe nanoparticles or carbides. Among our Fe–N–C catalysts, FeNC-50 with a Fe loading amount of 0.34 wt% showed the highest ORR performance regardless of the ammonia concentration. In particular, the difference in activity between the catalysts increased as the concentration increased. The FeNC-50 catalyst showed remarkable stability after 1000 cycles. Therefore, we believe that single-atom dispersion is an important factor in the development of stable non-precious catalysts with high activity and inactivity for the ORR and AOR, respectively.
Transition-metal phosphides (TMPs), a promising anode material for lithium-ion batteries (LIBs), are limited in application because of its serious volume effect in the cycle. In this work, a simple electrospinning strategy was proposed to restrict the grain size of CoP nanocrystals by nano-confined effect of carbon nanofibers with ligands. The addition of ligands not only could realize the uniform dispersion of CoP nanocrystals, but also strengthen the bond between the metals and carbon nanofibers. As a result, the CoP/CNF composite exhibits excellent lithium storage performance, and its reversible specific capacity could reach 1016.4 mAh g− 1 after 200 cycles at a current density of 200 mA g− 1. The research is anticipated to provide a new idea for the preparation of anode materials for lithium ion batteries.
This work describes the synthesis and characterization of a heterogeneous catalyst consisting of piperazine-functionalized reduced graphene oxide decorated with Fe3O4 nanoparticles ( Fe3O4@rGO-NH), and the study of its catalytic activity as a magnetic heterogeneous catalyst for the Pechmann synthesis of coumarins. Catalyst Fe3O4@ rGO-NH was fully characterized by various techniques, including IR, XRD, TEM, VSM, TGA, and elemental analysis. Then, the catalyst was used as an efficient and easy-separable heterogeneous catalyst for the solvent-free synthesis of some coumarins by Pechmann reaction. The reaction was optimized in terms of reaction time and temperature, catalyst dosage, and the presence/absence of the solvent. Finally, the reusability of the catalyst was studied.
This study examines how the concept of gender fluidity—viewing gender identity as a fluid and wide spectrum—is represented in modern knit fashion collections. The period spring/summer 2017–fall/winter 2021, when gender-related fashion keywords started attracting attention, was limited to the last five years, and the results of a case analysis focused on a total of 357 knit fashion photos are as follows. First, the androgynous compromise through the mixing of heterogeneous elements appears as a mix-and-match style due to the patchwork of heterogeneous materials and forms that borrow or share masculinity and femininity. Second, it was confirmed that the dismantling exaggeration caused by the destruction of the size and form of clothes was an avant-garde image that exaggerated the size or length of clothes or destroyed ideas and forms. Third, the exposed sensuality caused by the deformation of the fluid knitting technique was shown in the form of proudly expressing sexuality by exposing the body either using the cut-out technique or through the loose texture of the knit. Knit fashion can highlight decorative effects using handcrafted techniques and express a detailed or coarse sense of organization depending on the density. In addition, since it is possible to create a complex image by juxtaposing and mixing various knit structures, it was confirmed that it is a suitable material for expressing gender fluidity flowing between men and women in fashion.
A promising approach to enhance catalytic performance of supported heterogeneous nano-metal catalysts is to uniformly disperse active nanoparticles on the support. In this work, N-doped carbon-modified graphene (G@NC) nanosheet is designed and prepared to anchor Pd–Fe bimetallic nanoparticles (Pd–Fe/G@NC). The N-doped carbon modification on graphene surface could construct a sandwich-like structure (G@NC), which not only prevented the re-stacking of graphene nanosheets but also provided confined space for stable anchoring of bimetallic Pd–Fe nanoparticles. Benefitted from the unique structural property and synergetic effect of metal Pd and Fe species, the as-obtained Pd–Fe/G@NC composite displays excellent catalytic activity toward 4-nitrophenol reduction reaction with a turnover frequency of 613.2 min− 1, which is far superior to that of the mono-metal counterparts (Fe/G@NC and Pd/G@NC). More importantly, Pd–Fe/G@NC catalyst also exhibits favorable catalytic performance in the reduction of other nitroaromatic compounds (nitrobenzene, 4-nitrotoluene, 4-chloronitrobenzene, and so on). In addition, Pd–Fe/G@NC can catalyze the oxidation of furfuraldehyde to furoic acid with a high yield of 88.64%. This work provides a new guide for rationally designing and developing advanced supported heterogeneous bimetallic catalyst.
Background: Posterior capsule tightness (PCT), commonly seen in overhead athletes, is a soft tissue adaptation that is also noted in non-throwers. PCT is associated with scapular and humeral kinematic alterations, significant restriction of shoulder internal rotation (IR) range of motion (ROM), and significant scapular anterior tilting. Sleeper and cross-body stretches (CBS) are suggested for PCT and IR deficits, and have been modified since introduction. A novel modified sleeper stretch (NMSS) was designed in this study to prevent the risk of anterior translation of the humeral head. Though the effects of posterior shoulder stretching exercise have been widely studies, to the best of our knowledge, no previous studies have investigated the effectiveness of posterior shoulder exercises in decreasing scapular anterior tilting.
Objects: To compare the immediate effects of two posterior shoulder stretching exercises (NMSS and CBS) on scapular anterior tilting and shoulder IR ROM.
Methods: Thirty-two subjects with anteriorly tilted scapula and IR deficits [mean age: 24.3 ± 2.5 years; 15 males and 17 females] participated in this study. Subjects were randomly assigned to either the NMSS or CBS groups. Scapular anterior tilting (at rest and at shoulder 60° active IR) and shoulder IR ROM were measured before and immediately after intervention.
Results: Scapular anterior tilting significantly decreased, while the shoulder IR ROM significantly increased in both groups. However, there was no significant group-by-time interaction effect or significant difference between the groups.
Conclusion: Both stretching exercises were effective in restoring shoulder IR ROM and decreasing scapular anterior tilting.
Background: Scapular dyskinesis may cause not only rotator cuff (RC) tear but also weakness of the upper extremity, studies on scapular dyskinesis that may occur after RC repair is still lacking.
Objects: To determine whether scapular dsykinesis was present in patients after arthroscopic RC repair and to investigate the influence of passive scapular stabilization on upper extremity strength.
Methods: A total of 30 patients after RC repair participated in this study. To compare the scapula of the arthroscopic RC repair shoulder and the contralateral shoulder, the winged scapula (WS) was measured using a scapulometer and scapular dyskinesis was also classified by type. Fixed instruments for muscle strength measurements were used to measure upper extremity muscle strength differences depending on passive scapular stabilization position or natural scapular position. A chi-square test, an independent t-test and a 2-way mixed measures analysis of variance (ANOVA) was used as statistical analysis. In analyses, p < 0.05 was deemed to be statistically significant.
Results: Postoperative shoulder had a significant association with scapular dyskinesis and the WS compared to the contralateral shoulder (F = 0.052, p < 0.01). Postoperative shoulder, muscle strength in the shoulder abduction (p < 0.01), elbow flexion (p < 0.01) and forearm supination (p < 0.05) were significantly greater in the scapular stabilization position than in the scapular natural position.
Conclusion: Patients underwent arthroscopic RC repair had a significant association with scapular dyskinesis and muscle strength was improved by a passive scapular stabilization position, therefore scapular stabilization is important in rehabilitation program.
Background: Several factors contribute to shoulder pain, including abnormal neck posture, repeated use of the upper limbs, work involving raising the upper limbs above the head, and the effects of vibration. However, previous study has reported that constant vibration exposure could impact improvement of the stability on joints related with muscle recruitment and activation. For this difference reason, we need to verify for the complex study of relationship with repetitive upper limb movements, poor head posture, and constant vibration exposure.
Objects: Our study was made to investigate the influence of vibration exposure on the shoulder muscle activity during forward-head and over-head tasks with isometric shoulder flexion.
Methods: In a total of 22 healthy subjects, surface electromyography (EMG) data were collected from shoulder muscles (upper/lower trapezius, serratus anterior, and lumbar erector spinae) on tasks (neutral-head task [NHT], forward-head task [FHT], and over-head task [OHT]) with and without vibration exposure.
Results: In all tasks, the EMG data of the upper trapezius and serratus anterior significantly increased with vibration exposure (p < 0.05). Furthermore, the EMG data of the lumbar erector spinae significantly increased with vibration exposure in the NHT and FHT (p < 0.05).
Conclusion: We suggest that continuous vibration exposure during the use of hand-held tools in the tasks could be associated with harmful effects in the workplace. Lastly, we clinically need to examine the guidelines regarding the optimal posture and vibration exposure.
광택집나방과의 국내 미기록 2종인 큰광택집나방(Argyresthia subrimosa Meyrick)과 황갈광택집나방(Argyresthia umbrina Liu, Wang et Li)을 보고한다. 큰광택집나방은 서로 멀리 떨어진 울릉도와 제주도 두 곳에서 발견되었다. 두 지역에서의 큰광택집나방 개체군을 외형 및 생식기 특징으로 비교하였다. 황갈광택집나방이 모식산지인 중국 이외 지역에서 발견된 것은 처음이다. 두 종의 외형 및 생식기 특징을 사진과 함께 기술하 였다.
Background: Delivery workers repeatedly get in and out of trucks and walk or run to deliver packages during work. Iliotibial band syndrome (ITBS) is a well-known non-traumatic overuse injury of the lateral side of the knee caused by frequent knee flexion and extension. Hip muscle strength is among the factors that prevent lower extremity injuries. Although many studies have examined the relationship between ITBS and hip muscle strengths, there was no study comparing hip muscle strength and ratio between delivery workers with and without ITBS.
Objects: This study aimed to compare hip muscle strength and hip internal/external rotator and adductor/abductor strength ratios between delivery workers with and without ITBS.
Methods: Fourteen delivery workers with ITBS matched inclusion criteria in the present study among 20 participants. Because total sample size was required 28 subjects by G*power program (ver. 3.1.9.4; University of Trier), 14 delivery workers without ITBS were recruited. Hip muscle strengths were measured in a side-lying position using a Smart KEMA pulling sensor (KOREATECH Co. Ltd.). An independent t-test was used to compare hip muscle strengths and hip internal/external rotator and hip adductor/abductor strength ratios between delivery workers with and without ITBS.
Results: The adductor/abductor strength ratio was significantly greater in delivery workers without ITBS than in those with ITBS (p < 0.05). The strengths of the hip abductor, hip adductor, hip internal rotator, hip external rotator, and the ratio of internal/external rotator strengths were not significantly different between the delivery workers with and without ITBS (p > 0.05).
Conclusion: This study’s findings showed that delivery workers with ITBS had significantly lesser adductor/abductor strength ratio, while the strengths of the hip abductor and adductor muscles did not differ significantly. These results suggest that adductor/abductor strength ratio should be considered when evaluating and treating ITBS in delivery workers.
In additive manufacturing, the flowability of feedstock particles determines the quality of the parts that are affected by different parameters, including the chemistry and morphology of the powders and particle size distribution. In this study, the microstructures and flowabilities of gas-atomized heat-resistant alloys for additive manufacturing applications are investigated. A KHR45A alloy powder with a composition of Fe-30Cr-40Mn-1.8Nb (wt.%) is fabricated using gas atomization process. The microstructure and effect of powder chemistry and morphology on the flow behavior are investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and revolution powder analysis. The results reveal the formation of spherical particles composed of single-phase FCC dendritic structures after gas atomization. SEM observations show variations in the microstructures of the powder particles with different size distributions. Elemental distribution maps, line scans, and high-resolution XPS results indicate the presence of a Si-rich oxide accompanied by Fe, Cr, and Nb metal oxides in the outer layer of the powders. The flowability behavior is found to be induced by the particle size distribution, which can be attributed to the interparticle interactions and friction of particles with different sizes.