• Korean Journal of Breeding Science
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• v.51 no.3
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• pp.190-200
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• 2019

It is reported that the absence of lipoxygenase-3 (LOX-3) may contribute to a reduction in stale flavor after the storage of rice. To improve the quality of stored rice of the Korean japonica rice cultivar, we conducted a breeding program to develop near-isogenic rice without LOX-3 in the genetic background of Saenuri, a mega variety of Korea. In the first step of the breeding program, we used a donor parent of LOX-3 null, Daw Dam, and a recurrent japonica parent, Sindongjin, to develop HR27873-AC12 by backcross (BC₁), color test for introgression of lox-3, and anther culture for rapid fixation. In the second step, we used the donor parent, HR27873-AC12, and the recurrent parent, Saenuri, to develop HR28896-31-3-1-1 by backcross (BC₁), marker-assisted selection (MAS) for lox-3, and phenotypic selection (PS) for agronomic traits. Finally, in the third step, we developed HR30960-186-2-1-2-1 (Jeonju624), derived from a cross between Saenuri and HR28896-31-3-1-1, by MAS for lox-3 and PS with high selection pressure for agronomic characteristics. Jeonju624 was confirmed with the introgression of lox-3 by molecular marker. Jeonju624 was a mid-late maturing rice with similar agronomic characteristics to Saenuri, lodging tolerance with short culm, erect plant architecture, and resistance to bacterial blight and rice stripe virus. The yield components of Jeonju624 were mostly similar to Saenuri, except for the 1,000-grain weight of brown rice. The appearance of the grain of Jeonju624 was better than that of Saenuri, and the characteristics of cooked rice were similar to those of Saenuri. In the genetic background analysis using 406 KASP (Kompetitive Allele-Specific PCR) markers, Jeonju624 was confirmed to be the near-isogenic line (NIL) of Saenuri with a 95.8% recovery rate. Jeonju624 is the NIL of Saenuri without LOX-3, and overcomes the linkage drag of Daw Dam with similar agronomic characteristics and genetic background to Saenuri. Jeonju624 can be utilized as a practical cultivar to improve the quality of stored rice, breeding material for the introgression of lox-3, and genetic material to elucidate the effect of introgressed genes.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.346-358
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• 2023

Due to the acceleration of climate change or global warming, it is important to predict rice productivity in the future and investigate physiological changes in rice plants. The research aimed to explore how rice adapts to climate change by examining the response of nitrogen absorption and nitrogen use efficiency in rice under elevated levels of carbon dioxide and temperature, utilizing the SPAR system for analysis. The temperature increased by +4.7 ℃ in comparison to the period from 2001 to 2010, while the carbon dioxide concentration was held steady at 800 ppm, aligning with South Korea's late 21st-century RCP8.5 scenario. Nitrogen was applied as fertilizer at rates of 0, 9, and 18 kg 10a^-1, respectively. Under conditions of climate change, there was an 81% increase in the number of panicles compared to the present situation. However, grain weight decreased by 38% as a result of reduction in the grain filling rate. BNUE, indicative of the nitrogen use efficiency in plant biomass, exhibited a high value under climate change conditions. However, both NUEg and ANUE, associated with grain production, experienced a notable and significant decrease. In comparison to the current conditions, nitrogen uptake in leaves and stems increased by 100% and 151%, respectively. However, there was a 25% decrease in nitrogen uptake in the panicle. Likewise, the nitrogen content and NDFF (Nitrogen Derived from Fertilizer) in the sink organs, namely leaves and roots, were elevated in comparison to current levels. Therefore, it is imperative to ensure resources by mitigating the decrease in ripening rates under climate change conditions. Moreover, there seems to be a requirement for follow-up research to enhance the flow of photosynthetic products under climate change conditions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.387-397
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• 2023

Plant height is a growth parameter that provides visible insights into the plant's growth status and has a high correlation with yield, so it is widely used in crop breeding and cultivation research. Investigation of the growth characteristics of crops such as plant height has generally been conducted directly by humans using a ruler, but with the recent development of sensing and image analysis technology, research is being attempted to digitally convert growth measurement technology to efficiently investigate crop growth. In this study, the canopy height of rice grown at various nitrogen fertilization levels was measured using a laser scanner capable of precise measurement over a wide range, and a comparative analysis was performed with the actual plant height. As a result of comparing the point cloud data collected with a laser scanner and the actual plant height, it was confirmed that the estimated plant height measured based on the average height of the top 1% points showed the highest correlation with the actual plant height (R² = 0.93, RMSE = 2.73). Based on this, a linear regression equation was derived and used to convert the canopy height measured with a laser scanner to the actual plant height. The rice growth curve drawn by combining the actual and estimated plant height collected by various nitrogen fertilization conditions and growth period shows that the laser scanner-based canopy height measurement technology can be effectively utilized for assessing the plant height and growth of rice. In the future, 3D images derived from laser scanners are expected to be applicable to crop biomass estimation, plant shape analysis, etc., and can be used as a technology for digital conversion of conventional crop growth assessment methods.

• Korean Journal of Radiology
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• v.24 no.2
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• pp.145-154
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• 2023

Objective: We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes. Materials and Methods: In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months. Results: Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004). Conclusion: Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

• Journal of the Korean Wood Science and Technology
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• v.6 no.2
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• pp.3-19
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• 1978

Five species, Abies koreana Wilson (A. koreana), Castanopsis cuspidata var. Sieboldii Nakai (C. Cuspidata). Machilus thunbergii Sieb. et Zucc. (M. thunbergii), Styrax japonica (S. japonica), and Quercus acuta Thunberg(Q. acuta) growing in the southern part of Korea were selected for the investigation of wood properties. In order to evaluate the wood properties of these five species, anatomical, physical, mechanical, chemical and pulping characteristics were investigated. And this study also covered wood technological problems related to the drying, gluing, debarking, flooring, and wood workability so that these species might serve to the best advantage. The results obtained were summarized as follows: 1. The trunk of A. koreana with many knots was straight. However, the trunks of S. japonica and C. cuspidata were crooked. 2. A. koreana showed the longest and the widest ill the fiber morphology; 2.97mm in length, 39.3${\mu}$ in width. In general, fiber width of all the species investigated were greater than those of other Korean hardwoods. 3. The specific gravity of Q. acuta was 0.74${\pm}$0.03, and that of A.koreana was 0.34${\pm}$0.02. The range of specific gravity of the other species was 0.47-0.52. 4. The adsorption of water was propotioned inversely with the specific gravity, but the adsorption of humidity was proportioned with the specific gravity. In spite of their medium density, S. japonica showed the greatest adsorption, and M. thunbergii the least. The water adsorption of cross section was twice greater than that of lateral direction, and there was a slight difference in between the radial and the tangential direction. 5. Shrinkage for tested five species was ranged from 5.36 to 10.24% in tangential direction, and 2.83~6.13% in radial direction. Q. acuta recorded the greatest shrinkage rate, and A. koreana the least. The greater was the specific gravity, the larger was the shrinkage rate. 6. The mechanical properties of Q. acuta were similar to those of Quercus mongolica which grow in Kangwon-Do. Strength properties of C. cuspidata, M. thunbergii, A. koreana were equivalent to those of other Korean commercial woods with similar specific gravity, except S. japonica which showed slightly higher strength than that of other species with similar density. 7. Higher glue joint strength for urea and phenol adhesieves was recorded in the species of M. thunbergii and C. cuspidata, however, high-density species(Q. acuta) and even low-density species(A. koreana) did not show good joint strength. 8. The attractive figure of M. thunbergii in texture seemed to he appreciated for decoration. And the grain and texture of other species were proper for furniture and building materials. 9. All of the species except Q. acuta were considered good for wood workability. 10. The denser the specific gravity was, the longer the drying time took. However, severe drying defects were formed in M. thunbergii whose density was medium. 11. All the species were considered suitable for the flooring wood expect A. koreana whose density was light. 12. Pentosan component in all the species was great, and the amount of extractives in Q. acuta was worth noticing. 13. Yield in kraft pulp was above the level of economic pulp yield, i.e. 45% in all species. 14. Debarking was easy in the species of A. koreana and M. thunbergii, and debarking after being boiled in water was the most efficient in all species.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.49-69
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• 1988

In order to develop a cropping system that can produce garlic in the period of short supply from March to April, effects of low temperature treatment of seed bulbs and planting dates, starting date of low temperature treatment, days of low temperature treatment on plant growth, maturity and yield were studied in Southern strain, 'Namhae' and in Northern strain, 'Euiseong' of garlic (Allium sativum). The results obtained were as follows. In Sorthern strain, sprouting was significantly enhanced by low temperature treatment only in Sep. 14, and Sep. 29 plantings. Days to sprout were least in 30 days of low temperature treatment of Sep. 14 planting and in 45 days treatment of Sep. 29 planting. When considering on the beginning date of low temperature treatment, a marked difference was observed between treatments started before July 31 and after Aug. 15. Sprouting was most enhanced in 45 days low temperature treatment of Aug. 15 and Aug. 30 plantings. In Northern strain, sprouting was en hanced by low temperature treatment in planting from Sep. 29 to Nov. 13 and low temperature treatment for 60 days was most effective. Effect of low temperature treatment on early plant growth was observed in Sep. 14 and Sep. 29 plantings, but the effect on plant growth at intermediate stage or thereafter was observed in up to Oct. 29 plantings. Optimun days for low temperature treatment on growth enhancement was 45 and 60 days in Southern strain and 60 days in Northern strain in each planting dates. In Southern strain, the longer the low temperature treatment and the later the planting date the less the number of leaves developed. In Northern strain, normal leaves were not developed in plantings from Sep. 14 to Nov. 13. In Southern strain, clove differentiation and bulbing were earlist in 45 and 60 days treatment of Sep. 14, Sep. 29, and Oct. 14 planting initiated on July 31 and Aug. 15. In Northern strain, clove differentiation and bulbing were earlist in 60 days treatment of Oct. 14 planting initiated on Aug. 15 and Aug. 30. In treatment initiated later than above, longer the low temperature treatment the earlier the clove differentiation and bulbing in both Southern and Northern strains. The earlier the initiation date and the longer of low temperature treatment, the earlier bolting in southern strain. In Northern strain, bolting was most enhanced in 45 and 60 days of low temperature treatment initiated on Aug. 15 and Aug. 30. The longer the low temperature treatment in plantings thereafter, the earlier the bolting. The earlier the planting date garlic bulbs. Harvest date was earliest in 45 and 60 days low temperature treatment started from July 31 to Aug. 30 in Southern strain, and it was in 60 and 90 days low temperature treatment initiated from July 31 to Aug. 30 in Northern strain. Bulb weight was heaviest in 45 days low temperature treatment of Oct. 14 planting and next was in 45 days treatment of Sep. 29 planting in Southern strain. In Northern strain, bulb weight was heaviest in 60 days treatment of Oct. 14 planting and next was in 45 days treatment of Oct. 14 planting. When considered in the aspect of the beginning date of low temperature treatment, bulb weight was heaviest in 45 days treatment started on Aug. 30 in Southern strain and in 60 days treatment started on Aug. 15 in Northern strain. A high negative correlation between days to harvest and plant height on January 12, and a high positive correlation between days to harvest and days clove differentiation were observed. This indicates that enhanced plant growth and clove differentiation induced by low temperature treatment advanced the harvest date. A high negative correlation between bulb weight and days to clove differentiation, days to harvest suggests that the enhanced clove differentiation result and in heavier bulb weight. From the above results, it suggested that early crop of garlic can be harvested by planting at the period of Sep. 29 to Oct. 14 after 45 days of low temperature treatment of seed bulbs of Southern strain. Then harvest date can be shortened by 30 days compared to control and garlic can be harvested in early April.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.9-47
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• 1975

These experiments were caried out to study the effects of caponization and various hormone treatments upon meat production and improvement of meat quality of growing chicken. Sixtyseven days old 160 New Hampshire cockerels were treated and growth rate, carcass yield, change of weight of individual organs, meat composition and change of amino acid were measured and analysed. Otherwise change of testis and thyroid gland by hormone treatment were investigated histologically. The results obtained were as follows. 1. The effectst of caponization and hormone treatment upon meat production were; 1) Body weight of cockerels in D. E. S. group without caponization was increased. upon 96.86% than initial period and A. C. T. H. group was 104.22% but other groups and all carponization groups were lighter than those of control group. 2) Weekly body gain of D. E. S. group without caponization was best showing the significance (102.69 g) and the group with caponization were lower than those groups without caponization. 3) Carcass yield was best in Testo. group without caponization (831.2 g) and the group with caponization were lower than the group without caponization. 4) Carcass rate was highest in A. C. T. H. group with caponization and (67.22%) lowest in Testo. group without caponization (63.37%), but any significance was not recognized. 2. The effects of caponizatitn and hormone treatments upon the coposition of meat and amino acids were; 1) Any significance was not recognized between treated and untreated group about change of moisture, crude protein, crude ash and glycogen contents in meat. 2) Fat co tent in muscle in the all treated groups were higher than that of control group. 3) Extracts of group without caponization were higher than those of groups with caponization. 4) Lysin contents were highest in D. E. S. group with caponization (11. 12/ 16.0 g N) and generelly Testo. group was lower compared with D. E. S. group. 5) Histidine and Arginine contents were higher in the groups with caponization than without caponization. 6) Aspartic acid content were higher in D. E. S. group and A. C. T. H. group without depend on caponization. 7) Treonine content was higher in Testo. group without caponization and in the group with caponization and without hormone treatment compared with those of control group without caponization. 8) Serine content was decreased in the group with caponization and increased by D. E. S. and A. C. T. H treatment groups and glutamic acid was also decreased in Testo. group with out caponization. 9) Cystine content was decreased by Testo. treatment and was not appeared in Testo. group without caponization. 10) Valine content was lower in control group with caponization but significance was not recognized between other groups and control group without caponization. 11) Glycine, Alanine, Methionine. Isoleucine, Leucine, Thyrosine and Phenylalanine contents were not so difference between hormone treated groups and control group without caponization. 3. The effects of caponization and hormone treatment upon the change of organs were: 1) The weight of all organs were heaviest in D. E. S. group without caponization (18.5g) and lightest in A. C. T. H. group without caponization (155. 3g) but no significance was recognized between hormone treatment groups. 2) Heart weight was heaviest in D. E. S. group without caponization (7.46 g) and lightest in Testo. group without caponization (5.95 g). 3) Liver weight was heaviest in D. E. S. group without caponization(32.89g) and lightest in hormone untreated group with caponization(29.66g). Significance was not recognized. 4) Spleen weight was heaivest in Testo. group with caponization (3.22 g) and lightest in D. E. S. group without caponization(2.00g) in contrast with the other groups. High significance was recognized among the groups (P<0.01). 5) Cloacal thymus weight was lightest in D. E. S. group with or without caponization compared with control group without caponization. High significance was recognized among the groups. 6) Muscle fat content was not appeared in A. C. T. H. group with caponization, but it was highly increased in D. E. S. group with or without caponization. 7) Testis weight was lightest in D. E. S. group (0.38g) compared with control group (2.66g). Significance was recognized among the groups. 8) Large intestine, small intestine and cecum weight and length were heavier and longer in D. E. S. group without caponization and control group without caponization was lighter than those of hormone treated groups. 4. The effects of caponization and hormone treatment upon histological change of testis and thyroid gland: 1) The histological change of testis was significantly appeared in D. E. S. group that seminifirous tubles was slowly atrophied, the funtion of spernatogenesis was ceased, spermatocyte was changed as degeneration by pyknosis and karyorrhexis and interstitial cell was also atrophied, but in Testo. and A. C. T. H. group were similar as control group. 2) The histological change of thyroid gland in Testo. and A. C. T. H. groups without caponization were similar to that of control group without caponization, but in D. E. S. group without caponization, was changed squamously. Thyroid gland of the groups with caponization, epithelium of was atrophied and changed squamously as degeneration by pyknosis and karyorrhexis and the function of thyroid gland was slowly ceased in colloid and in hormone treated group with caponization.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.356-369
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• 1985

In Korea, inevitable researches for the blast control exactly started from 1927 by the organization of Office of Rural Development with the local extensive outbreak of panicle blast at Jeonlla Buk-Do Province in 1926. At present, the rice blast is still one of the most destructive and widespread diseases in spite of considerable contributions by rice scientists, particularly plant pathologists during last 55 years in Korea. Rice blast control and management are very difficult because of the marked variability in pathogenicity of the blast fungus. From the results obtained through the disease surveys during last 70 years, different 3 prevalence type of blast such as bimodal leaf-blast type, bimodal panicle-blast type and bimodal continual blast type were recognized. In generally speaking, pattern of blast outbreak is said to be characterized by severe outbreak of panicle blast after slight outbreak of leaf blast with discontinuity between leaf and panicle blast. So we have to pay much attention for successful management of panicle blast giving direct influence to rice yield. Main factors induce blast epidemic were pointed out to be breakdown of the disease resistance, nutritional unbalance such as excess application of nitrogen, delay of transplantation and longspell of rain fall by extensive surveys and researches on blast during last 70 years in Korea. The fact some of Japonica varieties such as Kokuryomiyako, Tamanishiki, Ginbozu and Pungok belong to varietal group A had been cultivated with extensive acrage over 30 years in this country should be mentioned by Korean rice scientists. Differences in field resistance between varieties in the same group are detectable and apparently small but sometimes epidemiologically significant differential effects may be found out in case of blast. Much more attention should be payed to accumulate the knowledges on field resistance for successful management of blast. Excess application of nitrogen is more effective to outbreak of panicle blast than that of leaf blast of IR varieties. In comparatively low level application of nitrogen infection rate of panicle blast of IR varieties is considerably high. Low temperature effects on outbreak of blast is very great. It results in remarkable increase of the inoculum potential on the leaf lesions and infection of panicle blast in leaf sheathes of IR varieties during the booting stage. In economic point of view, it is concluded that 5 times sprays of effective fungicides including 3 times before and 2 times after heading is good enough to control blast. We have experienced no one of control measures for blast is superior to all others. The integrated control measures was established as guideline of blast control around 1950 in Korea. This guideline must be helpful for rice growers as long as rice growing continue.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.31-40
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• 1982

For the effective control of weeds in mechanically transplanted paddy field weeding effects of naproanide ${\alpha}$-(${\beta}$-naphthoxy) propion anilide], pyrazolate [4-2, 4-dichlorobenzoyl)-1, 3-dimethyl pyrazol-5-yl-p-tolune sulphanate], chlormethoxynil (2, 4-dichloro-phenyl-4-nitro-3-methoxy phenyl ether), SL-49 [1-3dimethyl-4(2, 4dichlorobenzoyl)-5-phenacyloxy pyrazole], ACN (3-chloro-2-amino-l, 4-naphthoquinone) either alone or in combination with butachlor (2-chlor-2, 6-diethyl-N-buthoxymethyl acetanilide) were compared. Pyrazolate and SL-49 were most effective for the control of Sagittaria pygmaea MIQ. and Potomogeton distinctus A. BENN. including most annual weeds. Weeding effect of butachlor alone was very high for annuals, good for Cyperus serotinus ROTTB. and poor for S. pygmaea and P. distinctus. But the weeding effect of the combination of butachlor and pyrazolate was stronger than that of butachlor alone and therefore this mixture was effective for S. pygmaea, P. distinctus and C. serotinus including all the annual weeds. The combination of butachlor and SL-49 showed the same tendency as the combination of butachlor and pyrazolate. Naproanilide was not effective for the control of Echinochlor crusgalli P. BEAUV and less effective for Monochoria vaginalis PRESL, but excellent for S. pygmaea. By mixing butachlor with naproanilide weeding, spectrum for annuals and S. pygmaea was much increased by that for P. distinctus and C. serotinus was not satisfactory. ACN was not satisfactory for the control of all the tested weeds but the weeding effect was increased in general by mixing with butachlor. Chlormethoxynil was excellent for the control of annual weeds but it has no effect on C. serotinus, S. pygmaea and P. distinctus showing some initial controling effect but these weeds regrew afterwards. The weeding activity of ACN increased in combination with butachlor and the residual activity was stronger than that of ACN alone. A light crop injury was found at the initial period after treatments in all treated plots. The yield from all treated plots except those from plots treated with ACN, butachlor and naproanilide were not significantly different from the band weeded plot.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.75-99
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• 1983

The herbicidal properties of perfluidone [1,1,1-trifluoro-N-2-methyl-4-(phenylsulponyl) phenyl methanesulfonamide] were investigated in pots and paddy fields. At the rate of 2.0kg prod./10a, perfluidone did not cause any injury to the 4 leaf stage (LS) rice seedlings. Although the crop injury increased with increasing the application rate, the injury caused by 16kg prod. perfluidone/10a gave rise to only 30% yield reduction. The crop injury was greatest when perfluidone was applied 2 days before transplanting and decreased as the application time delayed. Perfluidone showed greater crop injury to the 3 LS seedlings, at more than 7cm water depth, and at high temperature than to the 4 LS seedlings, at 3-5cm water depth, and at low temperature. Indica and indica ${\times}$ japonica rice varieties were generally more sensitive to perfluidone than japonica rice variety. Perfluidone effectively controlled most of annual weeds and such perennial weeds as Sagittaria pygmaea MIQ., Potamogeton distinctus A. BENN, Cyperus serotinus ROTTB, Scirpus maritimus L., Eleocharis kuroguwai OHWL, and Scirpus hotarui OHWL, whereas Sagittaria trifolia L. and Polygonum hydropiper SPACH. were tolerent to perfluidone. The weeding effect decreased with increasing the leaching amount of water and the overflowing of irrigated water within 24 hours after the herbicide application. When the application time was done later than 8 days after transplanting, the perennial weeds were shown at deeper soil layers, and the standing water was deeper than 7cm, the effect tended to decrease. However, there was no difference in the weeding effect between soil types. Downward movement of perfluidone in flooded soil ranged from 2 to 8cm deep. The movement increased with increasing the leaching amount of water and the application rate and at a sandy loam soil which possessed less adsorptive capacity. Residual effect of perfluidone was found at 35 to 80 days after application, which varied such factors as Soil types. Increase in the leaching amount of water resulted in decrease in the period of the residual effect. The period was shorter at non-sterilized soil than at sterilized soil. The 0.75kg ai perfluidone + 1.5kg ai SL-49 (1,3-dimethyl-6-(2,4-dichlor-benzoyl)-5-phenacyloxy-pyrazole)/ha and 1.5kg ai perfluidone + 1.05kg ai bifenox (2,4-dichlorophenyl-3-methoxy carbonyl-4-nitro phenyl ether)/ha showed less crop injury than 1.5kg ai/ha perfluidone alone. However, the weeding effect of the former was similar to that of the later.