• 제목/요약/키워드: crossed effect

검색결과 106건 처리시간 0.023초

The Effect of Pain on Muscle Performance of Knee Extension and Flexion in Elite Athletes

  • Tak Yong Yoon;Yongwoo Lee;Doochul Shin
    • Physical Therapy Rehabilitation Science
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    • 제13권2호
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    • pp.223-230
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    • 2024
  • Objective: In this study, we compared the key indices of isokinetic tests for knee joint extension and flexion according to the presence or absence of pain in elite athletes with past knee and thigh injuries. Design: Crossed-sectional study Methods: This study was conducted on 33 elite athletes. The elite athletes who participated in this study were divided into a group with pain and a group without pain due to past knee and thigh injuries. The subjects in each group performed an isokinetic muscle strength test for knee joint extension and flexion. After the isokinetic muscle strength test, the main indices of the isokinetic test were compared between the pain group and the non-pain group. Results: In the comparison of the pain group and the non-pain group for 60°/s knee flexion and extension in elite athletes, there was a significant difference only in the torque max average/kg for knee extension. However, there was no statistically significant difference in all other variables. The comparison of the pain group and the non-pain group for 240°/s also showed a significant difference in the torque max average/kg for knee extension, and there was no statistically significant difference in all other variables. Conclusions: In subjects who have experienced previous knee or thigh injuries and have mild pain during strong isokinetic strength tests, torque average/kg is affected, but other strength variables are not affected. Therefore, it would be good to consider this aspect and use it as a basis for testing and training elite athletes.

주조연결된 니켈-크롬-베릴리움 주조체의 굽힘강도에 관한 비교연구 (FLEXURE STRENGTH OF CAST-JOINED CONNECTOR WITH Ni-Cr-Be ALLOY)

  • 정창모;전영찬;임장섭
    • 대한치과보철학회지
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    • 제36권6호
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    • pp.858-866
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    • 1998
  • Soldering is the usual method used to correct an unstable fixed partial denture framework at patient's try-in; However, presoldering base metal alloys is technique-sensitve and results are unstable because it is difficult to maintain uniform heat distribution and to prevent oxidation of an alloy. A cast-joining technique has been developed by Weiss and Munyon for repair, correction and addition to base metal framework. This joining technique eliminates the problem with presoldering of non-precious frameworks. The object of this study was to 1) compare the relative flexure strength and the joining effectiveness of Ni-Cr-Be cast in two pieces and 'pre-soldered' versus in two pieces and 'cast-joined'. 2) determine the effect of increasing the number of retentive grooves on the face of the cast and 3) determine the effect of the relative matched position of groove patterns on flexure strength. The joining effectiveness can be expressed by the ratio of the mean flexure stress of soldered or cast-joined specimens to that of one-piece cast. Resin rods 3mm in diameter were used as pattern of specimens for one-piece casted, presoldered, and cast-joined groups. Cast-joined specimens had two different patterns of retentive grooves on the joined faces. Type A had cross-shaped grooves 1mm in depth. 0.6mm in width. Type B was the same except for the addition of one more retentive groove. In the experiment connecting cast-joined specimens, half of specimens with type A pattern had their patterns on the faces of paired casts matched with each other as mirror image. With the rest pairs, it was proceeded that one of paired casts turned 45 degrees so that the patterns crossed. Half of specimens with type B pattern also had the patterns matched as mirror image; However, here, one of paired casts turned 90 degrees with the other pairs. Retentive groove in this study lacked the intentional undercuts, in contrast with the suggestion of Weiss and Munyon. The specimens were subjected to four-point flexural loading in an Instron testing machine. The midspan flexural stress was calculated at the point of initial plastic strain as determined from a strip-chart recorder or at the point of failure if this occured at a lower stress level. Within the scope of this study, the following results were obtained. 1. The presoldered group showed flexural strength at least 2 times higher than the cast-joined groups. Its joining effectiveness was 82%. 2. In cast-joined groups, the flexural strength of joints with type B patterns exhibited 1.5 times that of joints with type A patterns. Joining effectivenesses were 38% for type B patterns, 25-26% for type A patterns. 3. The relative matched position of groove patterns did not have any significant effect on flexural strength of the cast-joined specimens with either type A patterns or type B patterns(p>.05).

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The Effect of High Environmental Temperature and Nutrient Density on Pig Performance, Conformation and Carcass Characteristics under Restricted Feeding System

  • Hsia, L.C.;Lu, G.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권2호
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    • pp.250-258
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    • 2004
  • An experiment was conducted to examine the effect of a high environmental temperature on the performance, conformation, and carcass characteristics of pigs and the influence of diet. Thirty-six three-way crossed castrated male pigs with average initial body weight of 50.4 kg were used in the experiment. The pig were allocated to the following treatments: two environmental temperatures (20 and $30^{\circ}C$)${\times}$three dietary energy levels (2,980, 3,300 and 3,600 kcal/kg)${\times}$three protein levels (12.8, 15.2 and 17.2%). Daily weight gain was lighter (p<0.01) and feed: gain ratio lower (p<0.05) in pigs at $30^{\circ}C$ than for pigs at $20^{\circ}C$ The pigs at $30^{\circ}C$ were significantly taller with deeper bodies (p<0.05) and significantly longer (p<0.05) both vertically horizontally in the planum nasal when kept at $30^{\circ}C$. The width of body and the circumference of the neck were greater (p<0.05) at $20^{\circ}C$. The lean meat of the loin, middle section, ham, and hind section were significantly greater (p<0.05) in pigs kept at $30^{\circ}C$ and the belly was significantly heavier. The total unsaturated free fatty acids were significantly higher (p<0.05) in the body fat of pigs kept at $20^{\circ}C$ than in that of pigs at $30^{\circ}C$. The results indicated that when pigs are given very restricted same amounts of feed, they may need less energy to maintain their body temperature under moderately high environmental temperature ($30^{\circ}C$); consequently, their performance is better than that of pigs under optimum environmental temperature. The results showed very clearly that weight gain of pigs increased with increasing of dietary protein and energy content. The increasing of dietary protein content seemed more significant when content increasing to 17.2% compared with the 12.8 and 15.2% protein content treatments. The increasing of dietary energy content was more significant when content increasing to 3,600 compared with the other low energy content treatments.

Ideology, Politics, and Social Science Scholarship on the Responsibility of Intellectuals

  • Koerner, E.F.K.
    • 인문언어
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    • 제2권2호
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    • pp.51-84
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    • 2002
  • The 1990s have seen the publication of many books devoted to Language and Ideology (cf. Joseph & Taylor 1990. for one of the early ones) even though the term 'ideology' itself has remained ill-defined (Woolard 1998). The focus of attention has usually been placed on the particular use of language and often for some kind of 'political' ends, not on linguistic or other scholarship which might have been driven by some sort of ideology, i.e., a bundle of assumptions which themselves were taken as given. At least since Edward Said's 1978 book Orientalism, it has been clear to everyone that scholars construct their conceptualization of things in line with their understanding of the cultural, social, and political world in which they live, and that this often unreflected 'pre-understanding' effects their view of cultures that are different from theirs and more often than not geographically and temporally distant from theirs. This recognition has had a sobering effect no doubt, and Said's book has long since become 'mainstream.' Much more disturbing to the scholarly profession has been the publication of Martin Bernal's Black Athena in 1987, since it went much further, going beyond accusations of colonialism and cultural bias, in suggesting that the Western representation of Classical Greece over the past two hundred years was false and that what had been accepted until now about occidental antiquity must now be seen derived from African-Asiatic cultures of the Near East, notably that of the Ancient Egyptians, and that no other than Socrates should be seen as black man. While we may understand the intellectual climate in the United States that led academics to present 'myth as history' (Lefkowitz 1996), it is obvious that lines of regular scholarly principles of investigation have been crossed (cf Lefkowitz & Rogers 1996). The present paper investigates what may be seen as the ideological underpinnings of such work. After reviewing some recent scholarship in the area of linguistic historiography that have shown that academic work has never been 'value-neutral' (as may have been assumed or has been claimed by some practitioners), it is argued that in effect one must be aware of what Clemens Knobloch has recently termed Resonanzbedarf, i.e., the desire, whether conscious or not, of scholars-and probably scientists, too-to have their work recognized by the educated public and that, in so doing, their discourses tend to pick up on contemporary popular notions. These efforts may be harmless if everyone was to recognize these allusions and adoption of certain lexical. items(buzz words) as props or what Germans call Versatzstiicke, but history tells us that this has not always been the case. Still, as Hutton (1999) has shown, not all scholarship during the Third Reich for example can simply be dismissed as worthless because it was conducted in under a prevailing political ideology. Indeed, in seemingly innocent times, linguists can be shown to frame their argument in a way that makes them appear so utterly superior to their predecessors (cf. Lawson 2001). Upon closer inspection, those discourses turn out to be much like those of scholars in nationalistic environments that have tended to select their 'facts' to prove a particular hypothesis (cf., e.g., Koerner 2001). The article argues for scholars to take a more active role in exploding myths, scientifically unfounded claims, and ideologically driven distortions, especially those that are socially and politically harmful.

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Vitamins A and E in Carcass Fat from Japanese Black and F1 Cross Cattle

  • Irie, Masakazu;Inno, Y.;Ishizuka, Y.;Nishioka, T.;Morita, T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권9호
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    • pp.1266-1270
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    • 2006
  • This study was carried out to determine the contents of vitamins A and E in carcass fat from Japanese Black and F1 cross cattle, because the method of controlling the amount of vitamin A in feed has been used in the production of expensive beef with high marbling in Japan. We determined the contents of tocopherol and retinol in subcutaneous and perirenal fats for 40 carcasses of Japanese Black and F1 (Holstein${\times}$Japanese Black crossed) cattle that had been sent to market from 10 prefectures. In bovine fat, free ${\alpha}$-tocopherol was present in the greatest amount, the level of ${\gamma}$-tocopherol was about 10% and there was only a trace of ${\delta}$-tocopherol. The means${\pm}$standard deviation of ${\alpha}$-tocopherol content in subcutaneous and perirenal fats were $0.68{\pm}0.33mg/100g$ and $0.54{\pm}0.23mg/100g$, respectively. The means${\pm}$standard deviation of retinol content in subcutaneous and perirenal fats were $2.9{\pm}4.5{\mu}g/100g$ and $2.9{\pm}5.1{\mu}g/100g$, respectively. Both vitamins differed widely between animals and were present at a relatively low level compared to other reports (${\alpha}$-tocopherol 2.4-5.4 mg/100 g fat tissue and $30-220{\mu}g/100g$ muscle tissue). The correlation coefficients between subcutaneous and perirenal fats for retinol and ${\alpha}$-tocopherol content were 0.97 (p<0.01) and 0.82 (p<0.01), respectively, which showed high correlation. However, the correlation coefficients between retinol and ${\alpha}$-tocopherol contents for subcutaneous and perirenal fats were 0.11 and 0.08, respectively, which showed low correlation. Breed effect was observed in both vitamins. These results indicated that vitamins A and E in fat from Japanese Black and F1 cross cattle under the vitamin A controlling method are present at relatively low levels and feeds need to be supplemented with vitamin E.

인삼이 흰쥐의 조건회피반응 습득에 미치는 영향 (Effect of Ginseng on the acquisition of conditioned avoidance response in rats)

  • 홍사악;박찬웅;장현갑
    • 대한약리학회지
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    • 제12권1호
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    • pp.63-67
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    • 1976
  • 본 연구는 인삼 extract가 동물의 조건회피반응에 양호한 영향을 미친다는 petkov 및 홍사악등(洪思岳等)의 이전 연구 결과를 재확인하기 위해 인삼 extract 대신 화학적으로 더욱 정 선된 saponin으로 바꾸고 또 인삼 투여량도 다양하게 했을 때 그 결과가 어떻게 되는가를 알아 보고자 하였다. 60마리의 흰쥐 숫컷을 피험동물로 삼아 매일 실험 25분전에 인삼을 복강으로 투여하고 왕복회피형 shuttle box에서 하루 30시행씩 조건반응을 6일간 계속하였다. 총 180시행중 전기충격을 받지않고 성공적으로 회피한 조건반응수(CR)를 성적의 지표로 삼아 투여량에 따른 각 무리간의 CR수를 식염수 통제군의 CR수와 비교하였다. 모든 인삼 saponin을 투여한 집단들은 식염수 통제집단에 비해 조건회피반응 수가 많은 경향을 보여주나 통계적으로 유의미한 차이는 아니었다. 조건회피반응 중 동물들이 나타낸 배변수는 두 대량 인삼군 (50mg 및 100mg/kg)에서 통제군에 비해 유의미하게 적었다. 이 결과는 인삼이 학습에 어떠한 영향을 미치는지에 대해 확실한 증거를 제시치 못하는 것이나 대량의 인삼이 배변수를 줄이는 것으로 보아 대량의 인삼은 중추신경 안정작용이 있을 것으로 추측되게 한다.

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부스 바의 체결 및 중첩 구간에 따른 접촉 저항에 관한 연구 (A Study on the Contact Resistance according to the Tightening and Overlapping area of Bus Bar)

  • 김현우;손영득
    • 한국산학기술학회논문지
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    • 제19권7호
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    • pp.56-62
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    • 2018
  • 부스 바는 초고층 빌딩의 전력공급과 플랜트 산업의 전원 공급부 및 장비 제조 산업 분야의 배전반에 널리 사용되는 전기적인 접속 구조이다. 부스 바의 설계 시 고려해야 할 사항으로 사용 환경에 따른 재질, 전원 용량에 따른 단면적, 표면둘레의 길이, 체결 방법 등이 있다. 설계 시 충분한 전원 용량의 사이즈로 제작된 부스 바의 경우에도 실제 체결이 잘못 될 경우 열화에 의한 화재로 이어질 수 있다. 이러한 이유로 전기적 접촉부의 온도 상승에 대한 다양한 연구가 지속되어 왔다. 그러나 접촉부의 온도 상승은 결과에 기인한 현상이지 직접적인 원인은 아니다. 본 논문은 부스 바의 체결력과 중첩 구간에 따른 접촉 저항의 영향성에 대한 연구로 시편을 제작하여 저항의 변화를 측정하여 영향력을 분석하였다. 총 8개의 부스 바시편을 제작하여 측정하였고 각각의 시편을 교차하여 체결시 가해지는 체결력과 중첩 구간의 간격을 가변하여 저항을 측정하였다. 실험 결과를 통해 이러한 요인이 실제 접촉 저항의 변화에 어느 정도 기여하는지를 분석하여 안전한 전원 연결 장치의 모델을 제시하고자 한다.

Phosphorus-32에 의한 집파리의 표식효과 (I) (Studies on Phosphorus-32 Labeling of the House Fly ( I ))

  • 유준;정규회;권신한;김호원
    • 한국응용곤충학회지
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    • 제13권2호
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    • pp.93-97
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    • 1974
  • 방사성 동위원소를 이용한 해충의 생리 및 생태학적 연구를 위한 제반 기초자료를 얻기 위해서 집파리를 공시재료로 하며 유충기에 P-33를 희석농도별로 표식시킨 후에 충태별, 일영별, 부위별 및 $F_l$ 세대의 표식방사능에 대한 동태를 시험하있으며 사용계측기별 희석농도를 결정 하여본 결과는 다음과 같다. 1. 처리유충은 일령의 경과에 따라 표식방사능이 증가되었으나 노숙유충기인 6영기 이후 부터는 감소되었다. 2. 성충으로 우화된 후의 용피에는 약 $13.2\%$의 방사능이 잔류되었다. 3. 우화성충은 일령의 경과에 따라 표식방사능이 감소되었으며 성전체내에서 P-32의 생물학적 반감기는 0.14 일 이었다. 4. 성충체의 부위별 표식방사능 분포율은 복부에 가장 많은 방사능이 분포되어있으며 다음이 흉부, 두부, 지부, 시부 순으로 분포되어 있었다. 5. 표식성충 자웅간에 산난된 난과 부화유충의 100개당 표식방사능은 G.M. Counter를 사용할 경우 0.2 microcurie 이상에서 검출이 가능하였다. 6. 표식성충 숫놈과 정상 암놈과의 교미에서 산난된 난과 부화유충은 미량의 방사능을 바타냈으며. G.M. Counter의 경우 2.0 microcurie, Proportional Counter는 0.2 microcurie 이상에서만 검출 가능하였다. 7. P-32의 처리농도가 높아지면 성충의 사충율이 증가하는 경향이 있으므로 이상의 결과로 보아 처리농도 0.5 microcurie는 집파리를 표식시키는 가장 합리적인 처리농도라 할 수 있다.

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Effect of implant- and occlusal load location on stress distribution in Locator attachments of mandibular overdenture. A finite element study

  • Alvarez-Arenal, Angel;Gonzalez-Gonzalez, Ignacio;deLlanos-Lanchares, Hector;Martin-Fernandez, Elena;Brizuela-Velasco, Aritza;Ellacuria-Echebarria, Joseba
    • The Journal of Advanced Prosthodontics
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    • 제9권5호
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    • pp.371-380
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    • 2017
  • PURPOSE. The aim of this study is to evaluate and compare the stress distribution in Locator attachments in mandibular two-implant overdentures according to implant locations and different loading conditions. MATERIALS AND METHODS. Four three-dimensional finite element models were created, simulating two osseointegrated implants in the mandible to support two Locator attachments and an overdenture. The models simulated an overdenture with implants located in the position of the level of lateral incisors, canines, second premolars, and crossed implant. A 150 N vertical unilateral and bilateral load was applied at different locations and 40 N was also applied when combined with anterior load at the midline. Data for von Mises stresses in the abutment (matrix) of the attachment and the plastic insert (patrix) of the attachment were produced numerically, color-coded, and compared between the models for attachments and loading conditions. RESULTS. Regardless of the load, the greatest stress values were recorded in the overdenture attachments with implants at lateral incisor locations. In all models and load conditions, the attachment abutment (matrix) withstood a much greater stress than the insert plastic (patrix). Regardless of the model, when a unilateral load was applied, the load side Locator attachments recorded a much higher stress compared to the contralateral side. However, with load bilateral posterior alone or combined at midline load, the stress distribution was more symmetrical. The stress is distributed primarily in the occlusal and lateral surface of the insert plastic patrix and threadless area of the abutment (matrix). CONCLUSION. The overdenture model with lateral incisor level implants is the worst design in terms of biomechanical environment for the attachment components. The bilateral load in general favors a more uniform stress distribution in both attachments compared to a much greater stress registered with unilateral load in the load side attachments. Regardless of the implant positions and the occlusal load application site, the stress transferred to the insert plastic is much lower than that registered in the abutment.

Effect of Partial Replacement of Green Grass by Urea Treated Rice Straw in Winter on Milk Production of Crossbred Lactating Cows

  • Sanh, M.V.;Wiktorsson, H.;Ly, L.V.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권4호
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    • pp.543-548
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    • 2002
  • Fresh elephant grass was replaced by urea treated rice straw (UTRS) to evaluate the effects on milk production of crossed lactating cows. A total of 16 crossbred F1 cows (Holstein Friesian ${\times}$ Vietnamese Local Yellow), with a body weight of about 400 kg and lactation number from three to five, were used in the experiment. The experimental cows were blocked according to the milk yield of the previous eight weeks and divided into 4 homogenous groups. The experiment was conducted with a Latin Square design with 4 treatments and 4 periods. Each period was 4 weeks, with 2 weeks of feed adaptation and 2 weeks for data collection. The ratio of concentrate to roughage in the ration was 50:50. All cows were given constant amounts of elephant grass dry matter (DM), with ratios of 100% grass without UTRS (control treatment 100G), and 75% grass (75G), 50% grass (50G) and 25% grass (25G) with ad libitum UTRS. Daily total DM intake on 100G, 75G, 50G and 25G was 12.04, 12.31, 12.32 and 11.85 kg, and the daily ME intake was 121.6, 121.5, 119.4 and 114.3 MJ, respectively. The daily CP intake was similar for all treatments (1.85-1.91 kg). There was a difference (p<0.05) in daily milk yield between the 25G and the 100G and 75G (11.7 vs. 12.6 and 12.5 kg, respectively). Milk protein concentration was similar for all treatments, while a tendency to increased milk fat concentration following the increase of UTRS ratio was observed. The cows gained 4-5 kg body weight per month and showed first oestrus 3-4 months after calving. The overall feed conversion for milk production was not affected by ratio of UTRS in the ration. It is concluded that replacement of green grass by UTRS with a ratio of 50:50 for crossbred lactating cows is as good as feeding 100% green grass in terms of milk yield, body weight gain and feed conversion. UTRS can preferably replace green grass in daily rations for crossbred dairy cows in winter to cope with the shortage of green grass, with the ratio 1:1.