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        검색결과 829

        361.
        2012.06 구독 인증기관·개인회원 무료
        True hermaphrodites are animals of equivocal sex in which both male and female gonads develop simultaneously. The frequency of true hermaphroditism is higher in pigs than in other domestic animals. Two Korean pigs were diagnosed with true hermaphroditism showing ovotestes, epididymes, penes, and uteri. Histomorphologically, the testicular tissues consisted of Sertoli cells that were devoid of spermatogenic germ cells and showed proliferation of interstitial cells. However, the uteri were of normal architecture and had well-developed uterine endometrial glands. The samples were 38, XX female karyotype without the sex-determining region Y (SRY) gene. The findings of this study could contribute to the understanding of true hermaphroditism in the Korean pig industry. * This work was supported by a grant (Code# PJ008148) from BioGreen21 Program, Rural Development Administration, Republic of Korea.
        362.
        2012.06 구독 인증기관·개인회원 무료
        The aim of this study was to examine the effect of acteoside (the cyclin-dependent kinase inhibitor) on the SCNT efficiency with adult fibroblasts in dog. Canine adult fibroblasts were obtained from muscle and cell cycle of fibroblasts was synchronized by culturing to confluency, serum starvation and treating with 30 μM acteoside for 48 h. Cell cycle stages, cell cytotoxicity (apoptosis) and, prduction of reactive oxygen species (ROS) were analyzed using flow cytometry. The canine cells, prepared by confluent-cell culture or treating with 30 μM acteoside for 48 h, were injected into enucleated in vivo matured oocytes, the couplets were electrical fused and activated by calcium ionomycin. SCNT embryos using acteoside-treated fibroblasts were surgically transferred into oviducts of estrus cycle synchronized recipient dogs. In cell cycle synchronization (G0/G1), there was no significant difference between serum starvations (83.9%) and acteoside treated groups (81.3%) that were higher than confluent group (78.5%). In production of apoptosis, confluent and acteoside treated groups (4.3 and 4.5%, respectively) were generated less than serum starvation group (21.8%). In case of ROS, serum starvation group was induced a significantly higher than other groups. After synchronization of the donor cell cycle, either confluent or acteoside treated, cells were placed with enucleated in vivo-matured dog oocytes, fused by electric stimulation, activated, and transferred into naturally estrus-synchronized surrogates. Fusion and cleavage rate of acteoside treated group were 64.1 and 41.5%, which were higher than those of confluent group (53.9 and 20.6%, respectively). The reconstructed embryo development rates to 4-cell and 8-cell in acteoside treated group were 29.5 and 14.8%, respectively, while confluent group showed 11.1 and 3.2%, respectively. Total 54 SCNT embryos using acteoside-treated fibroblasts were transferred into oviducts of 2 recipient dogs and one recipient finally delivered one puppy, whereas din`t detected pregnancy on transfer of cloned embryos reconstructed with confluent cells in 6 surrogate dogs. In conclusion, the results of the current study demonstrated that canine fibroblasts could be successfully arrested at the G0/G1 stage with reduced the formation of ROS and apoptosis after acteoside treatment. This results may contribute to improve the effi-ciency of canine SCNT. * This research was supported by iPET (Grants 110056-3), Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea.
        363.
        2012.06 구독 인증기관·개인회원 무료
        Acteoside acts as an anti-oxidative activity and anti-apoptosis in the cells. But, it has been not studied on maturation and development of porcine oocytes. The aims of the present study were to examine the effects of acteoside on the morphological progress of meiosis, developmental competence, and ROS in porcine oocytes. Oocytes were matured in tissue culture medium-199, supplemented with acteoside at various concentrations: 0 (control), 10, 30 and 50 μM. The oocytes maturation rates of groups supplemented with acteoside were no significantly different (81.13, 85.96, 82.95 and 83.68%, respectively). Level of ROS was significantly decreased in acteoside treated group. Furthermore, the parthenogenetic blastocyst rate was significantly improved in 10 μM acteoside treated group compared with control group (44.83 vs. 27.75%). And we investigated effect of acteoside on the oocytes condition represented by cytoplasmic maturation by homogeneous distribution and formation of cytoplasmic organelles and regulation of apoptosis-related genes. In the results. during IVM, 10 μM acteoside treated oocytes showed that the mitochondria and lipid droplet were smaller and homogeneous distribution in cytoplasm compare with control oocytes. And reverse transcription polymerase chain reaction (RTPCR) of parthenogenetic blstocysts revealed that acteoside increased the anti-apoptotic genes (Mcl-1, Bcl-2 and Bcl-xL), whereas reduced the expression of pro-apoptotic genes (Bax and Bak). In conclusion, based on the results, the effect of acteoside on IVM was not attractive. However, in acteoside treated group, cytoplasmic maturation seemed to be improved with morphologically uniform distribution of cytoplasmic organelles. Furthermore, embryonic development in acteoside treated group was significantly highly increased than that of non-treated group. Our results represents that addition of acteoside to the IVM medium has a beneficial effect in physiology of porcine oocytes, providing a improved method for porcine oocytes in vitro. * This work was supported by a grant (Code# PJ008148) from BioGreen21 Program, Rural Development Administration, Republic of Korea.
        364.
        2012.06 구독 인증기관·개인회원 무료
        The objective of the current study was to describe in vitro embryo production in Hanwoo, analyzing oocytes yield and embryo production. The effects of oocytes production and the number of OPU procedures per animal on embryo production were also evaluated. OPU was done every 3~4 days during experimental period and collected oocytes were fertilized in vitro in both OPU and needle puncture groups. First, we compared the recovery rate of oocytes based on OPU session (Experiment 1). The average of collected oocytes was calculated from every 10 session. The average number of total oocytes recovered per animalonsessionwas 5.16 (mean). Second, we compared the recovery rate base on collection period of OPU (Experiment 2). The following results show the difference of the number of recovered oocytes in every month during the procedure between the months of session. Every animal shows the constant number of recovered oocytes for the first 5 months. However, the recovery rate of oocytes was decreased from month 6 to 8. Third, we compared the developmental rate to blastocyst in two groups (Experiment 3). Oocytes by needle puncture were fertilized with frozen-thawing semen; the cleavage rate 24~48 h after in vitro fertilization (IVF) was 75.8% and blastocyst development rate was 18.8% in needle puncture group. Even though there is lower cleavage rate after IVF in OPU group (61.1%), blastocyst development rate was higher compared with needle puncture group (28.4%). In conclusion, Blastocyst developmental rate could be increased by OPU than classical method of needle puncture. Improvement of bio- technique in collecting oocytes could be applied to understand the reproductive physiology in cattle, expecially Hanwoo. Therefore, further investigation should be done to clarify the efficiency and advantage of OPU involved in reproduction in animals and human being.
        365.
        2012.06 구독 인증기관·개인회원 무료
        SERPINB3 (also known Squamous cell carcinoma antigen 1, SCCA1) is involved in apoptosis, immune response, cell migration and invasiveness of cells. It has been investigated in various types of squamous cell carcinoma. Therefore we investigated the functional role of SERPINB3 gene in human epithelial ovarian cancer (EOC) using laying hens, the most relevant animal model. In 136 laying hens, EOC was found in 10 (7.4%). We compared the expression and localization of SERPINB3 using RT-PCR, quantitative RT-PCR, in situ hybridization and immunohistochemistry, and SERPINB3 activation was detected in chicken and human ovarian cancer cell lines using immunofluorescence microscopy. Thereafter, we examined the prognostic value of SERPINB3 expression in patients with EOC by multivariate linear logistic regression and Cox’ proportional hazard analyses. In present study, SERPINB3 mRNA was induced in cancerous ovaries (p< 0.01), and it was only expressed in the glandular epithelium(GE) of cancerous ovaries of laying hens. SERPINB3 protein was localized predominantly to the nucleus of glandular epithelium in cancerous ovaries of laying hens, and it was abundant in the nucleus of both chicken and human ovarian cancer cell lines. In 109 human patients with EOC, 15 (13.8%), 66 (60.6%) and 28 (25.7%) of those patients showed weak, moderate and strong expression of SERPINB3 protein, respectively. Strong expression of SERPINB3 protein was a prognostic factor for platinum resistance (adjusted OR, 5.94; 95% Confidence Limits, 1.21-29.15). Therefore SERPINB3 may play an important role in ovarian carcinogenesis and be a novel biomarker for predicting platinum resistance and a poor prognosis for survival in patients with EOC. This research was funded by the World Class University (WCU) program (R31-10056), Basic Science Research Program (2010- 0013078) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology and by the Next-Generation BioGreen 21 Program (No.PJ008142), Rural Development Administration, Republic of Korea.
        366.
        2012.05 구독 인증기관·개인회원 무료
        In the transcriptome surveys of Laodelphax striatellus, several cDNA sequences showed a high level of similarities to the insect picorna-like virus genomes. Interestingly, there was no sequence similarity between picorna-like virus sequences from the RSV-viruliferous and those from the non-viruliferous L. striatellus. Picorna-like virus from the non-viruliferous L. striatellus was a geographical isolate of Himetobi P virus (HiPV). The genome of the HiPV was 9,272 nt in length excluding the poly(A) tail and contained two open reading frames (ORFs), which were separated by a 176 nt intergenic region that functions as an internal ribosome entry site (IRES). The 5' ORF encodes the non-structural proteins and the 3' ORF encodes the capsid proteins. The partial genomic RNA of the picorna-like virus from the RSV-viruliferous L. striatellus, LsPV-2, was 8,769 nt in length excluding the poly(A) tail and contained a single, large open reading frame (nt 1–8,535) encoding a 2,845 aa polyprotein. In terms of sequence similarity, identity, and genome organization, LsPV-2 resembled insect picornalike viruses belonging to the family Iflaviridae. A phylogenetic analysis based on RNA-dependent RNA polymerase (RdRp) sequence showed that LsPV-2 was most closely related to the deformed wing virus (DWV). The HiPV and LsPV-2 were incompatible each other in L. striatellus, suggesting that these two picorna-like viruses may have important functions in transmission of the RSV.
        367.
        2012.05 구독 인증기관·개인회원 무료
        Plasmids from Bacillus thuringiensis have been implicated in pathogenicity as they carry the genes responsible for different types of diseases in mammals and insects. B. thuringiensis serovar mogi of a novel serogroup (H3a3b3d), which showed mosquitocidal activity against Anopheles sinensis and Culex pipiens pallens, was isolated from fallen leaves in Mungyeong city, Republic of Korea. In contrast to the complicated plasmid profiles of B. thuringiensis H3 serotype strains, the B. thuringiensis serovar mogi contained only megaplasmid (> 30 MDa) on which the toxin genes were occasionally located. Sequence analysis using 454-pyrosequencing revealed that the megaplasmid harbored at least seven putative cry genes, showing about 84%, 75%, 73%, 58%, 84%, 39% and 75% similarities in amino acid sequences with Cry27Aa, Cry19Ba, Cry20-like, Cry56Aa, Cry39ORF2, Cry8Ba and Cry40ORF2, respectively. These cry genes were cloned to the Escherichia coli-B. thuringiensis shuttle vector, pHT1K, and then introduced into an acrystalliferous B. thuringiensis Cry-B strain for further molecular characterization. This novel 3a3b3d type strain, B. thuringiensis serovar mogi, could be used as a good resource for studying unknown mosquitocidal cry genes.
        368.
        2012.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to examine the degree of knowledge of care workers working at long term care hospitals and nursing homes on pressure ulcer. A total of 81 care workers including 34 at long term care hospitals and 47 at nursing homes were surveyed. 24 questions were used to evaluate their degree of knowledge on pressure ulcer. Their knowledge on pressure ulcer scored 12.84 out of the total score of 24 points(SD=3.40), which was equal to 53.50 (SD=24.23) out of 100 points. Their knowledge on the prevention of pressure ulcer was highest among the subareas of evaluation. Their knowledge on pressure ulcer statistically significantly differed according to education on pressure ulcer(P<.05). A pressure ulcer is a skin disorder that may be prevented and cured. At this point when long term care facilities are rapidly increasing, care workers highlevel knowledge on and good management of pressure ulcer is very important. Practically educating them on pressure ulcer including the provision of recent, updated relevant knowledge will be necessary.
        4,000원
        369.
        2011.12 구독 인증기관 무료, 개인회원 유료
        The experimental manipulation of protooncogenes and their gene products is a valuable research tool for the study of human neoplasia. In this study, the recently identified human cervical cancer protooncogene (HccR-2) was expressed in transgenic mice under the control of the tetracycline regulatory system. The phenotype observed was similar in many respects to human chronic neutrophilic leukemia (CNL). Thus, the HccR-2 transgenic mouse model is important not only for investigating the biological properties of the HccR-2 protooncogene in vivo, but also for analyzing the mechanisms involved in the progression of CNL.
        4,000원
        370.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 환경스트레스 저항성이 증진된 페튜니아를 개발하기 위하여 NDPK2유전자 도입 형질전환 계통 NDPK2-7-1와 SOD2 유전자 도입 형질전환 계통 SOD2- 2-1-1-35간의 교잡에 의해 획득된 후대들의 비생물적 스트레스 저항성을 조사하기 위해 수행되었다. 비 생물적 스트레스 유발원인 메틸바이올로젠(methyl viologen, MV) 100 μM과 200 μM 처리에서 교잡후대들은 그들의 교배 모본 SOD2 유전자나 NDPK2 유전자가 단독으로 도 입된 형질전환 계통이나 비형질전환체 보다 메틸바이 올로젠에 의한 피해를 적게 받았다. 이는 SOD2 유전 자나 NDPK2 유전자가 단독으로 도입된 형질전환 계 통간 교잡에 의해 획득된 후대들이 그들의 교배모본 (SOD2 유전자나 NDPK2 유전자가 단독으로 도입된 형질전환 계통)이나 비형질전환체 보다 산화적 스트레 스에 대한 저항성이 증진되었음을 증명해 준다고 할 수 있다. 이들 교잡후대들은 초장 등 11종류의 양적형질의 특성이 비형질전환체에 비해 약간 길거나 짧긴 하였지 만 비형질전환체와 거의 유사하였으며, 꽃 색갈이나 모양 또한 그들의 교배모본 (SOD2 유전자나 NDPK2 유전 자가 단독으로 도입된 형질전환 계통)이나 비형질전환 체와 차이가 없었다.
        4,000원
        373.
        2011.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to examine the effects of gait training using functional electrical stimulation on the improvement of hemiplegic patients' functions for balance and gait velocity. The subjects of the experiment were determined to be 10 each hemiplegic patients who had been diagnosed with stroke or brain damage six months or longer earlier assigned to an experimental group and a control group respectively. The subjects were evaluated before the experiment using Tetrax and 10M gait tests, received gait training five times a week for four weeks using functional electrical stimulation and were evaluated after the experiment in the same method as used in the evaluation before the experiment. In order to examine differences between the experimental group that received gait training using functional electrical stimulation and the control group that was treated by functional electrical stimulation and received gait training thereafter, differences between before and after the experiment were analyzed using paired sample t-tests and differences in changes after the experiment between the experimental group and the control group were analyzed using independent sample t-tests in order to compare the two groups with each other. Experimental results showed significant differences in weight bearing, balance and gait velocity between before and after the experiment in the experimental group(p<.05). In the control group, whereas weight bearing and gait velocity did not show any significant difference between before and after the experiment(p>.05), balance showed significant differences(p<.05). Weight bearing, balance and gait velocity change rates showed significant differences between the experimental group and the control group(p<.05). In conclusion, it was indicated that gait training using functional electrical stimulation is effective for enhancing stroke patients' weight bearing rates, balance abilities and gait velocity.
        4,000원
        374.
        2011.10 구독 인증기관·개인회원 무료
        Testes‐derived unipotent male germ‐line stem (GS) cells can acquire multipotency under appropriate culture conditions to become mGS cells which can contribute to all three germ‐layers. This study was designed to investigate the epigenetic characteristics of mGS cells derived from adult mouse testes (maGS cells). The GS cells were isolated from 4 6 week DBA mouse and were cultured in Dulbecco’s modified Eagle Medium supplemented with 15% (v/v) fetal bovine serum, 1,000 U/ml LIF, 4 ng/ml GDNF at 37℃ in an humidified atmosphere of 5% CO2 in air to derive the maGS cells. The multipotency of maGS cells were verified by morphological and gene expression analyses, teratoma formation upon transplantation into nude mouse and in vitro differentiation ability. Bisulfite genomic sequencing revealed that GS cells had androgenetic DNA methylation pattern at the Igf2‐H19, Gnas‐Nespas , and Dlk1‐Dio3 imprinted gene clusters which changed to hemi‐zygotic embryonic stem (ES)‐cell like pattern in the maGS cells. Western blot analysis, using modification‐ and residue‐specific antibodies, revealed that both maGS and ES cells had similar level of histone di‐methylation at 4th and 27th lysine residue of histone 3 (H3K4me2 and H3K27me2) which represent “bivalent domain” for regulating self‐renewal and differentiation of mouse ES cells. Both maGS and ES cells also shared similar hisone modification for H3K9me2, H3K79me2, H3K9ac and H3K18ac. However, maGS cells had higher level of H3K- 36me2 and H3S10p. These data suggest that maGS and ES cells share several epigenetic characteristics but they also have their own unique epigenetic marks that may be useful as a molecular marker for their identification.
        375.
        2011.10 구독 인증기관·개인회원 무료
        The objective of this study was to evaluate in vitro production of bovine embryos in Hanwoo. Oocytes were collected by ovum pick up (OPU) from ovaries of genetically high-value Hanwoo or by needle puncture from ovaries of slaughtered cattle. OPU was done every 3 4 days duing experimental period and collected oocytes were fertilized in vitro in both OPU and needle puncture groups. First, We compared the in vitro maturation rate in two groups (Experiment 1). 545 oocytes were recoverd from 4 females by 32 trials of OPU and then 433 oocytes were shown MⅡ stage after in vitro maturation (79.4%). In case of needle puncture group, 1905 oocytes were collected and then 1420 oocytes were matured to MⅡ stage during in vitro culture(74.5%). Second, we compared the developmental rate to blastocyst in two groups (Experiment 2). 1420 oocyte by needle puncture were fertilized with frozen-thawing semen; the cleavage rate 24 48 h after in vitro fertilization (IVF) was 88.6% and blastocyst development rate was 20.5% in needle puncture group. Even though there is lower cleavage rate after IVF in OPU group (84.8%), blastocyst development rate was higher compared with needle puncture group (26.4%). In conclusion, Blastocyst developmental rate could be increased by OPU than classical method of needle puncture. Improvement of bio-technique in collecting oocytes could be applied to understand the reproductive physiology in cattle, expecially Hanwoo. Therefore, further investigation should be done to clarify the efficiency and advantage of OPU involved in reproduction in animals and human being. This research was suppoted by Imsil-gun agricultural technology service center.
        376.
        2011.10 구독 인증기관·개인회원 무료
        Rice stripe virus (RSV), the type member of the genus Tenuivirus, causes rice stripe disease and the viral transmission is mediated through the sucking by small brown planthopper, Laodelphax striatellus. Considerations have been mainly focused on the protection of rice from RSV and/or the planthopper, rather than the interaction between RSV and the insect. To clarify the interaction, in this work, mRNA was extracted from RSV-viruliferous planthopper with non-viruliferous control, and expressed sequence tag (EST) databases were generated based on 454 GS-FLX pyrosequencing technology for comparative analysis. RSV-viruliferous planthopper had ca. 2500 isotigs, which included genes on biological process (19%), cellular component (13%), molecular function (22%) and no hits (46%) from gene ontology (GO) analysis; this structure was similar to the control. However, in the viruliferous planthopper, 109 isotigs were up-regulated and 660 isotigs were down-regulated, compared to the non-viruliferous control. These RSV-dependently regulated genes may have important function in the behavior of planthopper or the transmission of RSV.
        377.
        2011.10 구독 인증기관·개인회원 무료
        The green peach aphid, Myzus persicae Sulzer, is one of the most important pests affecting protected and open-grown crops, because they cause direct damage by feeding on crops and indirect damage as virus vectors. It has recently become a serious problem because of the continuous use of insecticide resulting in resistance among green peach aphid population. Thus, the development of entomopathogenic fungi as aphid biocontrol agents has received increasing interest as part of integrated control strategies. In this study, we report the screening result of pathogenic fungi for the control of green peach aphid. Initial screenings were performed using 347 isolates of putative pathogenic fungi from Korea soils. As results, 20 isolates of entomopathogenic fungi were isolated from cadavers of green peach aphid supporting fungal conidiation. These isolates were identified as three strains of Lecanicillium attenuatum, nine strains of Beauveria bassiana, one strain of Metarhizium anisopliae, one strain of Metarhizium flavoviride, five strains of Paecilomyces lilacinus, one strain of Aspergillus sp. by microscopic examination, genetic sequencing of the ITS region and Universally Primed PCR (UP-PCR). Based on the screening results, twenty isolates were tested for their pathogenicity against adult green peach aphid. All fungal isolates were pathogenic to green peach aphid but mortality varied with isolates. These entomopathogenic fungi may be useful to develop eco-friendly insecticide to control green peach aphid.
        378.
        2011.10 구독 인증기관·개인회원 무료
        Plasmids from Bacillus thuringiensis have been implicated in pathogenicity as they carry the genes responsible for different types of diseases that in mammals and insects. A novel serogroup (H3a3b3d), B. thuringiensis strain K4 which showed mosquitocidal activity against Anopheles sinensis and Culex pipiens pallens, was isolated from fallen leaves in Mungyeong city, Republic of Korea. In contrast to the complicated plasmid profiles of B. thuringiensis H3 serotype strains, the strain K4 (designated as serovar mogi) had only one large plasmid (>200kb) on which the toxin genes were occasionally located. A 454 pyrosequencing was used for the complete sequencing of the large plasmid. The sequence analysis showed that k4 plasmid had at least seven putative cry genes, ending up to showing 84%, 75%, 73%, 58%, 84%, 39% and 75% homology with Cry27Aa, Cry19Ba, Cry20-like, Cry56Aa, Cry39ORF2, Cry8Ba and Cry40ORF2 toxins in amino acids, respectively. This novel 3a3b3d type strain, B. thuringiensis serovar mogi, can be used as a good resource for studying unknown mosquitocidal cry genes. The E. coli-B. thuringiensis shuttle vector, pHT1K was used to clone these cry genes for characterization. In each clone, the level of transcription and production of crystal proteins will be investigated in near the future.
        379.
        2011.10 구독 인증기관·개인회원 무료
        Among 154 putative ORFs of Autographa californica multiple nucleopolyhedrovirus (AcMNPV), ac78 and ac79 are highly conserved genes in baculovirus, but their functions in the virus life cycle have been unknown so far. To determine their roles in AcMNPV replication, knockout mutants, ac78KO and ac79KO, were constructed using the plasmid capture system (PCS). Real-Time PCR analysis showed that both of ac78 and ac79 transcripts were first detected at 6 hours post-infection, and accumulated to maximum at 24 hours post-infection, suggesting that both of ac78 and ac79 are belong to late gene. When the genomic DNA of ac78KO was transfected into Sf9 cells, viral replication was restricted to a single cell infection. These results demonstrated that the ac78 play an important role in BV production, and therefore is essential for AcMNPV to mount a successful infection. Whereas Sf9 cells infected with the ac79KO showed normal viral symptoms such as rounding and swelling, OBs were not observed from majority of infected cells. These results suggested that the ac79 might play an important role in OB production.
        380.
        2011.10 구독 인증기관·개인회원 무료
        The entomopathogenic fungi were an important natural pathogenic of insects that has been developed as potential biological control agents for many important agricultural, forest and medical pests. Several these fungi produce a wide range of secondary metabolites with high therapeutic value as antibiotics, cytotoxic substances, insecticides, compounds that promote or inhibit growth, attractor and repellent. Therefore, this study was performed to select the antibacterial activity of liquid culture filtrates of 347 entomopathogenic fungi form Korea soils against two pathogenic bacteria including Ralstonia solanacearum and Escherichia coli using novel method which represents a quick and easily applicable tool obtaining large number of samples. As results, eight-five strains (24%) and seventy-six strains (22%) of these fungal metabolites produced anti-R. solanacearum and anti-E. coli compounds, respectively. The preferential antibacterial activity against R. solanacearum and E. coli gives evidence that these entomopathogenic fungal metabolites might be useful as an agent for bacteria control and the technique was simple to operate and allowed a large number of samples to be handled concurrently.