• 제목/요약/키워드: Normal oval

검색결과 62건 처리시간 0.023초

On the Breeding of “CSR18${\times}$CSR19”- A Robust Bivoltine Hybrid of Silkworm, Bombyx mori L. for the Tropics

  • Kumar, N.Suresh;Basavaraja, H.K.;Kumar, C.M.Kishor;Reddy, N.Mal;Datta, R.K.
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제5권2호
    • /
    • pp.153-162
    • /
    • 2002
  • Earlier breeding experiments undertaken at Central Sericultural Research and Training Institute, Mysore, India since a decade had resulted in the development of many productive and qualitatively superior bivoltine hybrids. However, the hot climatic conditions of tropics prevailing particularly in summer are not conducive to rear these high yielding bivoltine hybrids. This has necessitated breeding of compatible bivoltine hybrids for year-round rearing. Accordingly, the Japanese hybrid, B2Ol ${\times}$ BCS12 which was found to be tolerant to high temperature was used as breeding resource material. Following hybridization and selection rearing of silkworms was taken up in SERICATRON (Environmental chamber with precise and automatic control facilities for uniform maintenance of temperature and humidity) at high temperature of $36{\times}1^{\circ}C$ and 85${\times}$5% RH in fifth instar and the control batches at $25{\times}1^{\circ}C$ and 65{\times}$5% RH. Directional selection was resorted to the batches reared at 36$\pm$1$^{\circ}C$ till F$_{5}$ keeping pupation rate as important selection criteria. From $F_{2}% onwards the experiment was modified in such a way as to conduct normal rearing every alternate generation to regain the lost vitality due to continuous exposure to high temperature and high humidity stress. At $F_{2}$ , Oval and dumb-bell cocoons were separated out and designated as CSR18 and CSR19, respectively. By utilizing these lines at $F_{12}$, the hybrid CSR18$\times$CSR19 was prepared and studied for the thermotolerance by subjecting to stress condition at high temperature of 36$\pm$1$^{\circ}C$ and 85$\pm$5% RH in fifth instar and the control batches at $25{\times}1^{\circ}C$ and 65${\times}$5% RH. The better performance of CSR18${\times}$CSR19 (survival > 88%) at $36{\times}1^{\circ}C$ clearly indicates the general superiority of CSR18${\times}$CSR19 with regard to high temperature tolerance over the productive hybrids and CSR18$\times$CSR19 can perform well in varied agro-climatic conditions of the tropics with optimum qualitative and quantitative characteristics.s.

간세포암종의 세침흡인 세포학적 소견 - 247예에 대한 연구 - (Fine Needle Aspiration Cytology of Hepatocellular Carcinoma - A Study on 247 Cases -)

  • 이광길;이종태;최수임;박찬일
    • 대한세포병리학회지
    • /
    • 제1권1호
    • /
    • pp.1-17
    • /
    • 1990
  • Hepatocellular carcinoma (HCC) is malignant tumor frequently occurring in Koreans. There have been few reports regarding the cytologic findings of fine needle aspiration (FNA) of HCC. Most have suggested a diagnostic problem in the cytology distinguishing HCC from some benign hepatic lesions-for example, a regeneration nodule in cirrhosis and liver cell adenoma. In spite of its high frequency in Korea, no cytologic study has been reported, concerning the FNA of HCC. In an attempt to achieve cytologic criteria for the diagnosis of HCC, the authors studied retrospectively cytopathologic findings of 247 cases of HCC. These cases were confirmed either by histoiogic examination including lobectomy, biopsy, or ceil block material, or, when tissue diagnosis was unavailable, by a high serum alpha-fetoprotein level (over 400 I. U.). All aspiration smears were stained by the Papanicolaou method. In each case, the smears were analyzed for cell patterns and various cytomorphology of the tumor cells. The smear background was assessed for the presence of tumor cell necrosis and inflammatory components and compared to that of metastatic carcinomas. The cell patterns were classified as trabecular, acinar, dispersed, and irregular. The cytologic parameters analyzed included the degree of nuclear atypia and the presence of mitoses, intranuclear cytoplasmic inclusions, nucleolar prominency, endothelial lining, multinucleated giant cells, eosinophiic globules, bile, and Mallory body. Most of the FNA of HCC showed markedly cellular smears. The tumor cells were most frequently arranged in a trabecular pattern (80.3%). The irregular (12.6%), the acinar (5.5%), and the dispersed patterns (1.7%) followed in decreasing frequency. Individual hepatoma cells were larger than normal liver cells. However, they had morphologic features characteristic of the hepatic cells the cells were round or polygonal, their cytoplasm was abundant and granular with eosinophilic or amphophilic stainability, and their nuclei were round to oval, located centrally, and tended to have prominent nucleoli. Anaplasia and pleomorphism of tumor cells were generally mild to moderate. These findings existed even in very well differentiated cases. Mitotic figures were present in about 85% of the cases. Prominent nucleoli were observed only in about half the cases. The frequency of other cytologic features was as follows intranuclear cytoplasmic inclusion in 86.8% : endothelial lining in 56.1% : bile in 19.8% : and giant cells in 60.1%. Clear cells were often present in 11.7%, Most aspiration smears of HCC displayed clean background without necrosis or inflammatory material in contrast to the dirty, necrotic background of metastatic cancers and cholangiocarcinomas. Based on the above mentioned features, it is suqqested that the cytologic critieria most important for the diagnosis of HCC include a markedly cellular smear, trabecular pattern, hepatocytoid appearance of tumor cells, endothelial lining, the presence of bile, giant cells, intranuclear cytoplasmic inclusions, and prominent nucleoli, Among these, trabecular pattern, endothelial lining, giant cells and clean smear background are points to be considered in differentiating HCC from metastatic and cholangiocellular carcinoma.

  • PDF

Axenfeld-Rieger 증후군과 연관된 치과적 이상 (Dental anomalies associated with Axenfeld-Rieger syndrome)

  • 김기림;이두영;김승혜;이상휘;최병재;이제호
    • 대한장애인치과학회지
    • /
    • 제6권2호
    • /
    • pp.94-98
    • /
    • 2010
  • 저자는 Axenfeld-Rieger 증후군을 가지는 5세 8개월 연환에 대한 구강 및 두개 안면에 대한 임상적, 방사선학적 관찰을 통해 다음과 같은 지견을 얻었다. 1. 본 증례의 환아는 Axenfeld-Rieger 증후군의 전형적인 안과적, 구강적, 전신적 특징인 녹내장, 동공이상, 제탈장, 지연된 골령, 다수 치아 및 치배 결손, 상악 저성장 등을 보였다. 2. 이에 대한 주기적인 관찰과 적절한 시기의 치료개입이 중요하다. 3. 치과의사에 의한 조기진단이 녹내장 등에 의한 시력상실을 방지하기 위해 중요하다.

  • PDF

여대생의 발 유형과 선호 구두 형태와의 관계 (Relationship of Types of Foot Shape and Favorite Shoes Shape of Female University Students)

  • 이진희;김경희
    • 한국생활과학회지
    • /
    • 제12권1호
    • /
    • pp.75-84
    • /
    • 2003
  • The objective of this paper was to analyse the foot type of female university students by the direct and indirect measure of foot and the measures of foot outline. The results were as follow: 1. The length and the width of foot were small and ankle slender and the modification of the big toe slight. 2. The analysis on the 16 measure items revealed five factors; the first factor was related to the width and girth of foot, the second one to the length of foot, the third one to the transformation of the little toe, the fourth one to the height of foot, the fifth one to transformation of the big toe. 3. The grouping on the shape of foot revealed three types. The inline angle of foot was the smallest in average in the type 1, while it appeared to be middle in the other types. The wider foot shapes were grouped as type 2 because their inline and outline angles of foot were the biggest in average. In the type 3, the big toe was curved a lot, since it was the largest in average. 4. From the naked eye measuring method, classification from which toe was popped-out told that Egyptian foot was 30.9%, Greek foot 27.9%. On the other hand, the instrumental method showed that Egyptian foot was 57.3%, Squared foot 35.3% and Greek foot 7.4%. 5. The result from the analysis about the traits of foot shape by the degree of the arch formation of bottom foot, showed that 33.8% had the normal foot, 66.2% slightly flat foot or middle one. There was no one with rigid flat foot. 6. The shoes size they declared were that 240cm was 33.3%, 235cm 18.1% and 245cm 18.1%. The shape of their shoe heel were flat heel(34.8%), cuban heel(25.5%), and narrow straight heel(19.9%); and that of the shoe toe were round toe(25.4%), oval toe(20.4%) and squared toe(20.4%). 7. The discomforting parts when they wear shoes were the little toe(35.4%), the rear of foot(13.9%), and the width of foot(13.9%), which was related to their dislike of shoe with the pointed toe.

  • PDF

이소성 낭성 흉선종 1예 (A Case of Ectopic Cystic Thymoma)

  • 이재형;김일옥;이희경;민경환;김상헌;김태형;손장원;윤호주;신동호;박찬금;강정호;박성수
    • Tuberculosis and Respiratory Diseases
    • /
    • 제62권4호
    • /
    • pp.331-335
    • /
    • 2007
  • 전종격동 하부에 심장과 연접한 이소성 흉선종은 폐암뿐 아니라 흉선종, 생식세포암, 림프종, 전이성 종양 등의 여러 질환과 감별이 필요하다. 병리조직상으로는 이소성 흉선종에 대한 주의가 없는 경우, 미분화상피암, 암성병변의 림프절 전이, 또는 림프구가 우세하게 관찰되는 경우 림프종 등으로 오진될 수도 있으므로 감별진단에 있어 주의가 필요하다. 또한 낭성 흉선종은 이러한 감별진단을 더욱 어렵게 한다. 저자들은 하부 종격동에 심장 우측과 연접하여 발생한 이소성 낭성 흉선종 환자 1예를 경험하였기에 보고하는 바이다.

고슴도치 십이지장 점막의 장내분비세포의 미세구조 (Fine Structures of the Enteroendocrine Cells in the Duodenal Mucosa of the Hedgehog, Erinaceus koreanus)

  • 최월봉;원무호;서지은
    • Applied Microscopy
    • /
    • 제17권1호
    • /
    • pp.83-97
    • /
    • 1987
  • In order to discriminate the enteroendocrine cell types in the mucosal epithelium of the normal duodenum of the Korean hedgehog (Erinaceus koreanus). The tissues were fixed in the mixture of 1% paraformaldehyde and 1% glutaraldehyde in phosphate buffer (pH 7.2), and postfixed in 2% osmium tetroxide (phosphate buffer, pH 7.2). They were embedded in Araldite, and the ultrathin sections were made by LKB-V ultratome following the inspection of semithin sections stained with toluidine blue-borax solutions. Ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100B electron microscope. At least six types of enteroendocrine cells distributed in the mucosal epithelium of the duodenum were identified according to their morphological characteristics mainly based on the size, shape, number and electron density of the secretory granules. Type I cells had moderately developed organelles. The secretory granules were pleomorphic ($370X510nm$), and the granule cores with high electron density were enveloped in limiting membrane and characterized by a narrow halo. Type II cells contained an indented nucleus and well-developed organelles. The secretory granules were round (350 nm) and classified in two kinds by electron density, moderate and high. Both granules were surrounded by limiting membrane and those with high electron density showed often a wide halo. Type III cells had an indented nucleus. The secretory granules with various electron density were round (220 nm) in shape. The granules with high electron density were enveloped in limiting membrane and characterized by a narrow halo, but those with low or moderate electron density had not been observed the limiting membrane. Type IV cells contained an indented nucleus and moderately developed organelles. The secretory granules were round (180 nm) in shape, and the granule cores with high electron density were enveloped in limiting membrane and showed often a wide halo. Type V cells had a large amount of rough endoplasmic reticulum. Secretory granules with low or moderate electron density were round (230 nm) in shape, and surrounded by limiting membrane and showed a narrow halo. Type VI cells contained an oval nucleus and well-developed organelles, especially Golgi complex. The secretory granules with high electron density were round (210 nm) in shape. The granules were enveloped in limiting membrane and showed often a wide halo.

  • PDF

점액암의 영상소견 (Imaging Features of Mucinous Breast Carcinoma)

  • 한혜정;김성헌;차은숙;김현숙;강봉주;최재정;이지혜;이아원
    • Investigative Magnetic Resonance Imaging
    • /
    • 제14권1호
    • /
    • pp.21-30
    • /
    • 2010
  • 목적: 점액암의 영상소견에 대해서 알아 보고, 조직학적 분화도에 따른 영상 소견의 차이를 알아보고자 하였다. 대상과 방법: 수술을 통해 점액암으로 확진된 29명의 환자를 대상으로 유방촬영술과 초음파 검사, 그리고 자기 공명 영상 소견을 BI-RADS에 따라서 후향적으로 분석하였다. 또한 점액암의 조직학적 분화도를 고분화, 중증도분화, 미분화 등급으로 나눠서 이에 따른 영상소견의 차이를 통계학적으로 분석하였다. 결과: 총 20예의 유방 촬영에서 17예 (85%)가 종괴로 보였고 3예는 정상소견이었다. 총 27예의 초음파 검사에서 점액암은 난원형 (59.2%)의 미세소엽성 변연 (55.5%)을 가지거나 불균일한 등에코 (74%)의 종괴로 보였다. 총 21예의 자기공명영상에서 점액암은 소엽상의 변연(76.2%), 매끄러운 변연(86%)의 종괴로 불균일한 조영증강(61.9%)을 보이는 경우가 흔하였다. 역동성 조영 증가 그래프에서 지연시 유실형 양상 (52.3%)을 보였다. 고분화 점액암이 갑자기 끝나는 종괴의 경계를 보이는 것 외에는 점액암의 분화도에 따른 영상소견의 차이는 없었다. 결론: 점액암의 분화도에 따른 차이는 중등도 분화 점액암과 비교하여 고분화 점액암이 갑자기 끝나는 종괴의 경계를 보이는 것이었다. 대부분의 점액암은 자기공명영상에서 불균일한 조영증강과 지연시 유실형 양상을 보였다.

Apoptotic Activity of Curcumin and EF-24 in HTB-41 Human Salivary Gland Epidermoid Carcinoma Cells

  • Kim, Ji-Won;Lee, Seul Ah;Go, Dae-San;Park, Byung-Sun;Kim, Su-Gwan;Yu, Sun-Kyoung;Oh, Ji-Su;Kim, Chun Sung;Kim, Jeongsun;Park, Jong-Tae;Kim, Do Kyung
    • International Journal of Oral Biology
    • /
    • 제40권2호
    • /
    • pp.63-69
    • /
    • 2015
  • Curcumin (diferuloylmethane), a constituent of turmeric powder derived from the rhizome of Curcuma longa, has been shown to inhibit the growth of various types of cancer cells by regulating cell proliferation and apoptosis. However, a need exists to design more effective analogs because of curcumin's poor intestinal absorption. EF-24 (diphenyl difluoroketone), the monoketone analog of curcumin, has shown good efficacy in anticancer screens. However, the effects of curcumin and EF-24 on salivary gland epidermoid carcinoma cells are not clearly established. The main goal of this study was to investigate the effects of curcumin and EF-24 on cell growth and induction of apoptosis in human salivary gland epidermoid carcinoma cells. Our studies showed that curcumin and EF-24 inhibited the growth of HTB-41 cells in a dose- and time-dependent manner, and the potency of EF-24 was > 34-fold that of curcumin. Treatment with curcumin or EF-24 resulted in nuclear condensation and fragmentation in HTB-41 cells, whereas the control HTB-41 cell nuclei retained their normal regular and oval shape. Curcumin and EF-24 promoted proteolytic cleavages of procaspase-3/-7/-9, resulting in an increase in the amount of cleaved caspase-3/-7/-9 in the HTB-41 cells. Caspase-3 and -7 activities were detected in viable HTB-41 cells treated with curcumin or EF-24. These results suggest that the curcumin and EF-24 inhibit cell proliferation and induce apoptosis in HTB-41 human salivary gland epidermoid carcinoma cells, and that they may have potential properties as an anti-cancer drug therapy.

LL/2 Cells접종에 의한 C57 BL/6 Mouse 폐에서의 전이과정 (Formation of Metastases in C57 BL/6 Mouse Lung)

  • 김지현;이지영;김우갑;황우익
    • Applied Microscopy
    • /
    • 제29권2호
    • /
    • pp.137-147
    • /
    • 1999
  • 본 연구에서는 C57 BL/6 mouse의 폐가 기원인 LL/2 cell line을 이용하여 C57 BL/6 mouse의 폐에 인위적으로 전이를 유도하여 그 과정을 광학 및 전자현미경을 이용하여 관찰하였고, 형성된 암세포가 기존 폐포세포에 apoptosis를 유도하는지 여부를 in situ Apoptosis kit를 이용하여 살펴 보았다. in vitro에서 배양된 LL/2 cell과 이 LL/2 cell을 C57 BL/6 mouse 꼬리 정맥에 주사한 후 약 21일된 mouse 폐에서 관찰되는 암세포의 미세구조를 비교하면 방추형의 세포모양에서 난형 또는 구형의 모양으로 변한 것 외에 커다란 변화가 없었다. mouse 폐에서 암세포는 림프소절과 폐상피의 모세혈관주위에서 처음 나타났으며 왕성하게 세포분열하여 커다란 암세포 덩어리를 형성하였다. 암세포 덩어리 주변의 정상 폐조직은 광학현미경 관찰에서 폐포구조가 다소 납작해졌다. 그러나 투과전자현미경 관찰에서 세포 자체의 손상을 볼 수 없었으며 오히려 암세포 덩어리 안에서 기존 정상 폐포세포들이 관찰 되었다. 또한 커다란 암세포 덩어리 안에서 일부의 암세포들이 apoptosis되고 있었다. 주사 후 22일에서 호중성 백혈구가 폐포와 암세포주변에서 31일은 암세포덩어리안에서 혈소판과 함께 다량 관찰되었다. 이상의 결과에서 LL/w cell은 C57 BL/6 mouse의 폐에 효과적으로 전이를 일으키며 왕성한 세포분열에 의해 커다란 암세포 덩어리를 형성한다. 이 암세포 덩어리가 커지면서 기존 폐포에 물리적인 압박을 주었으나 폐상피세포에서 apoptosis를 유도하지 않았다. 그러나 아주 커다랗게 형성된 암세포 덩어리에서 일부 암세포들이 띠를 이루면서 apoptosis되고 있었는데, 이는 암세포 덩어리가 커지는 만큼 형성되어야 할 혈관형성에 장애가 생긴 결과로 생각된다.분되었다. 6. 미세동맥의 외막은 섬유모세포의 아주 가느다란 돌기들로 형성되어 있었으며 군데군데 교원섬유들이 관찰되었다.acil을 투여하였을 경우, 초기 (4일)에는 발세포와 혈관사이막의 경우 mitomycin C 투여군에서와 비슷한 미세구조적 변화를 보였으나, 7일군에서는 거의 정상군의 소견과 비슷한 모습을 보였다. 이와 같은 결과는 콩팥토리를 비롯한 콩팥조직에 미치는 세포독성은 mitomycin C가 5-fluorouracil에 비하여 훨씬 더 강하기 때문이라고 생각된다.應)된 틸라피아의 제 2차(次) 아가미엽(葉)의 미세구조(微細構造)는 적응기간(適應期間) 동안 표면이 울퉁불퉁한 특징을 나타내었고, 투과전자현미경(透過電子顯微鏡)에 의해서는 해수(海水)에 노출된 염분세포내(鹽分細胞內)에 길게 변형된 미토콘드리아가 관찰되었으며, 잘 발달된 cristae가 확인되었고, 담수(淡水)에 서식하던 개체의 염분세포(鹽分細胞)보다 그 수가 증가하였다. 이와같이 미토콘드리아가 풍부한 염분세포의 존재를 통해서 해수(海水)에 적응하는 동안 일어나는 저삼투압조절(低渗透壓調節) 작용(作用)에 중요한 역할을 하는 것이라 사료된다. 해수(海水)에 적응(適應)된 대부분의 틸라피아는 신장(腎臟)의 보우만 주머니를 가득 채운 신사구체(腎絲球體)를 가지고 있으며, 신사구체(腎絲球體)의 수축은 담수(淡水)에 적응된 개체보다 10%o, 20%o, 30%o에 적응된 개체에서 훨씬 더 많이 발생되었고, 울혈현상(鬱血現象)은 10%o보다 20%o, 30%o에 적응(適應)된 개체의 신장조직(腎臟組織)에서 더많이 발생되었다. 틸라피아의 신사구체(腎絲球體)는 담수(淡水)에서 10%o의 해수(海水)로 이주된지 14일(日) 이후에 신장(腎臟)에서 수축된 것으로 나타났다. 30%o의 해수(海水)에 적응(適應)된 틸라피아의 평균 신사구체(腎絲球體)의 면적은 담수(淡水)에

  • PDF

Origin of limestone conglomerates in the Choson Supergroup(Cambro-Ordovician), mid-east Korea

  • Kwon Y.K.;Chough S.K.;Choi D.K.;Lee D.J.
    • 한국석유지질학회:학술대회논문집
    • /
    • 한국석유지질학회 2001년도 제8차 학술발표회 발표논문집
    • /
    • pp.63-65
    • /
    • 2001
  • The Chosen Supergroup (Cambro-Ordovician), mid-east Korea consists mainly of shallow marine carbonates and contains a variety of limestone conglomerates. These conglomerates largely comprise oligomictic, rounded lime-mudstone clasts of various size and shape (equant, oval, discoidal, tabular, and irregular) and dolomitic shale matrices. Most clasts are characterized by jigsaw-fit (mosaic), disorganized, or edgewise fabric and autoclastic lithology. Each conglomerate layer is commonly interbedded with limestone-dolomitic shale couplets and occasionally underlain by fractured limestone layer, capped by calcareous shale. According to composition, characteristic sedimentary structures, and fabric, limestone conglomerates in the Hwajol, Tumugol, Makkol, and Mungok formations of Chosen Supergroup can be classified into 4 types: (1) disorganized polymictic conglomerate (Cd), (2) horizontally stratified polymictic conglomerate (Cs), (3) mosaic conglomerate (Cm), and (4) disorganized/edgewise oligomictic conglomerate (Cd/e). These conglomerates are either depositional (Cd and Cs) or diagenetic (Cm and Cd/e) in origin. Depositional conglomerates are interpreted as storm deposits, tidal channel fills, or transgressive lag deposits. On the other hand, diagenetic conglomerates are not deposited by normal sedimentary processes, but formed by post-depositional diagenetic processes. Diagenetic conglomerates in the Chosen Supergroup are characterized by autoclastic and oligomictic lithology of lime-mudstone clasts, jigsaw-fit (mosaic) fabric, edgewise fabric, and a gradual transition from the underlying bed (Table 1). Autoclastic and oligomictic lithologies may be indicative of subsurface brecciation (fragmentation). Consolidation of lime-mudstone clasts pre-requisite for brecciation may result from dissolution and reprecipitation of CaCO3 by degradation of organic matter during burial. Jigsaw-fit fabric has been considered as evidence for in situ fragmentation. The edgewise fabric is most likely formed by expulsion of pore fluid during compaction. The lower boundary of intraformational conglomerates of depositional origin is commonly sharp and erosional. In contrast, diagenetic conglomerate layers mostly show a gradual transition from the underlying unit, which is indicative of progressive fragmentation upward (Fig. 1). The underlying fractured limestone layer also shows evidence for in situ fragmentation such as jigsaw-fit fabric and the same lithology as the overlying conglomerate layer (Fig, 1). Evidence from the conglomerate beds in the Chosen Supergroup suggests that diagenetic conglomerates are formed by in situ subsurface fragmentation of limestone layers and rounding of the fragments. In situ subsurface fragmentation may be primarily due to compaction, dewatering (upward-moving pore fluids), and dissolution, accompanying volume reduction. This process commonly occurs under the conditions of (1) alternating layers of carbonate-rich and carbonate-poor sediments and (B) early differential cementation of carbonate-rich layers. Differential cementation commonly takes place between alternating beds of carbonate-rich and clay-rich layers, because high carbonate content promotes cementation, whereas clay inhibits cementation. After deposition of alternating beds and differential cementation, with progressive burial, upward-moving pore fluid may raise pore-pressure in the upper part of limestone layers, due to commonly overlying impermeable shale layers (or beds). The high pore-pressure may reinforce propagation of fragmentation and cause upward-expulsion of pore fluid which probably produces edgewise fabric of tabular clasts. The fluidized flow then extends laterally, causing reorientation and further rounding of clasts. This process is analogous to that of autobrecciation, which can be analogously termed autoconglomeration. This is a fragmentation and rounding process whereby earlier semiconsolidated portions of limestone are incorporated into still fluid portions. The rounding may be due mainly to immiscibility and surface tension of lime-mud. The progressive rounding of the fragmented clasts probably results from grain attrition by fluidized flow. A synthetic study of limestone conglomerate beds in the Chosen Supergroup suggests that very small percent of the conglomerate layers are of depositional origin, whereas the rest, more than $80\%$, are of diagenetic origin. The common occurrence of diagenetic conglomerates warrants further study on limestone conglomerates elsewhere in the world.

  • PDF