In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochond...In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochondrial DNA gene Cytochrome b.Both analyses resolved R.altaica as nesting deeply within R.arvalis.Most samples of the nominal R.altaica from the Altai region and specimens from Central Siberia shared a haplotype with R.arvalis based on the network analysis.The matrilineal relationships suggested that R.altaica should be considered as a junior synonym of R.arvalis.Furthermore,our study suggested that the species group division of Chinese brown frogs should be re-evaluated within a phylogenetic context.展开更多
Aim To study the effects of tetrodotoxin (TTX) combined with acetylsalicylic acid (ASA) on nociceptive stimulus in mice. Methods To assess the antinociceptive effects of TTX, ASA or TTX plus ASA, the acetic acid-i...Aim To study the effects of tetrodotoxin (TTX) combined with acetylsalicylic acid (ASA) on nociceptive stimulus in mice. Methods To assess the antinociceptive effects of TTX, ASA or TTX plus ASA, the acetic acid-induced abdominal constriction test and formalin pain test were used. Results TTX (0.5 - 4.0 μg· kg^-1 ) or ASA (25 - 200 mg· kg^-1 ) im produced a significant inhibition of acetic acid-induced abdominal constriction. The median inhibitory doses (ID508) were 2.1 μg· kg^-1 for TTX( and 64 mg· kg^-1 for ASA. TTX and ASA also showed a dose-dependent inhibition of the second phase response in the formalin pain model, the ID508, being 2.3μg·kg^-1 and 74.2 mg· kg^-1, respectively. The ihteraction between TTX and ASA was synergistic, as evidenced by the fact that (1) when ASA alone compared with the combination of TTX (0.79 μg · kg^-1 or 0.39μg· kg^-1 ) and ASA, the ID508, of ASA reduced from 64.0 mg· kg^-1 to 5.8 mg· kg^-1 or 12.6 mg· kg^-1, and from 74.2 mg· kg^-1 to 7.4 mg· kg^-1 or 13.0 mg· kg^-1 on tile two models of nociceptive tests, respectively; and that (2) synergism in the analgesic effects was shown by isobiolographic analysis. Conclusion TTX, ASA and the combination of the two drags produce analgesic effects in acetic acid-induced abdominal constriction test and formalin-induced pain test. The interactions between TTX and ASA may be useful in developing novel analgesic agents.展开更多
In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chic...In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. Viral suspensions were subjected to inactivation with BEI and formalin for pre-set time in- tervals. BEI was employed at concentrations of 0.001 and 0.002 mol/L while formalin was used at 0.1% and 0.2%. Sampling was done at 6, 12, 24, 36 and 48 h of incubation and samples were tested for their inactivation status in 9-day-old embryonated eggs and 3-week-old broiler chickens. IBDV was completely inactivated by 0.001 and 0.002 mol/L BEI after 36 h of incubation at 37℃, whereas formalin at 0. 1% and 0.2% concentrations inactivated IBDV in 24 h.展开更多
The article presents research findings related to recreational use of forests located in protected mountainous areas with forestage of over 80%. The study was designed to identify recreational potential of the Carpath...The article presents research findings related to recreational use of forests located in protected mountainous areas with forestage of over 80%. The study was designed to identify recreational potential of the Carpathian national parks (Bieszczady National Park, Bahia G6ra National Park, Goree National Park and Magura National Park; southern Poland) and to compare these findings with the actual number of visitors. The information received on the recreational potential of parks is important from the point of view of protection of natural resources and the financial situation of the parks. The calculated ratio may be an effective tool of management for park administration, that allows to reconcile statutory social and protective functions of national parks. The study determined the recreational potential of the forests with the use of recreational valorisation method designed for areas with varied terrain, and the evaluated factors included the stands of trees with their habitat and land relief. The permissible number of national park visitors, expressed as man- hour/ha/year ranges from 19.31 in Bieszczady National Park (BG: 19~ 35' E, 49~ 35' N) to 32.06 in in Bieszczady National Park (B: 22~ 40' E, 49~ lo' N). In 3 out of 4 investigated parks, Magura National Park (M: 21025' E, 49~ 30' N), Gorce National Park (G: 20~ lo' E, 49~ 35' N), B) recreation carrying capacity was not exceeded, whether or not the strictly protected area is taken into account. Only in BG was the recreation carrying capacity exceeded by nearly 24%, or by 85% if the strictly protected area isexcluded from tourism-related exploitation. The presented procedure for monitoring access to mountain forests in national parks, from the viewpoint of natural resources conservation, can be applied in other mountainous areas covered with forests and exposed to tourist and recreational traffic, and in forests facing particular risk of recreational damage, e.g. in urban and suburban forests growing in areas with varied orography.展开更多
Alverine dtrate is a commonly used smooth muscle relaxant agent.A MEDLINE search on January 2004 revealed only 1 report implicating the hepatotoxicity of this agent.A 34- year-old woman was investigated because of the...Alverine dtrate is a commonly used smooth muscle relaxant agent.A MEDLINE search on January 2004 revealed only 1 report implicating the hepatotoxicity of this agent.A 34- year-old woman was investigated because of the finding of elevated liver function tests on biochemical screening.Other etiologies of hepatitis were appropriately ruled out and elevated enzymes were ascribed to alverine citrate treatment. Although alverine citrate hepatotoxicity was related to an immune mechanism in the first case,several features such as absence of predictable dose-dependent toxicity of alverine citrate in a previous study and absence of hypersensitivity manifestations in our patient are suggestive of a metabolic type of idiosyncratic toxicity.展开更多
Livelihood of the people in Nepal hills depends much upon forest resources in addition to farming as forest plays a critical role in the well being of the farming households where access to alternative sources, such a...Livelihood of the people in Nepal hills depends much upon forest resources in addition to farming as forest plays a critical role in the well being of the farming households where access to alternative sources, such as energy for cooking, nutrition for animals, materials for fertilizer and constructing materials for shelter, are limited. Thus, the well being of the people in the hills is directly affected by the management of these forest resources. This issue was addressed in this paper by examining the forest resource management practices and its effect on well being of rural people in two different stages in a village lying in the steep hill of Mahabharat Range in the southern hills of Kathmandu valley, Lalitpur District. The main ethnic/caste groups in the village are Brahmin/Chhetri (high Hindu caste), Magar/Tamang (Tibeto Burmans) and Kami (occupational caste: cobbler). Currently there are four community forest users groups, with mixed ethnic membership, organized to manage the forest resources. The endowments, weak institutional settings, before 1990 helped the Bhramins, Magars and Tamangs to get access into the private forest endowment, which made them easy to get access to the forest resources, mainly fuel wood, fodder and timber in 1990 and enhanced their well beings. But the socially backward Kami could not get benefit from the institutions that existed during that time and had less chance to enhance their well beings. After the set up of different endowments during late 1990s, i.e., hand over of forest management to usersgroupsin line with the concept of community forest, environment to use the forest resources became better for all the groups, along with the management of the forest. This enhanced the well beings of all the groups in the study village. However, the ability of Kami to use the forest resources to enhance their well beings was still lacking behind. The reason was partially due to the difference in endowments carried over from the endowments before 1990, and partly due to their occupational work and location of their settlements.展开更多
AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients ...AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients with stage I-IV CRC diagnosed by preoperative biopsy. KRAS mutational status was determined by pyrosequencing analysis of DNA obtained from formalin-fixed paraffin-embedded (FFPE) tumor tissues. The KRAS G12D mutation was then analyzed by ddPCR in FFPE tumors and stool-derived DNA from patients with this point mutation. Wild-type (WT) tumors, as determined by pyrosequencing, were included as controls; analysis of FFPE tissue and stool-derived DNA by ddPCR was performed for these patients as well.RESULTSAmong the total 70 patients included, KRAS mutations were detected by pyrosequencing in 32 (45.71%), whereas 38 (54.29%) had WT tumors. The frequency of KRAS mutations was higher in left-sided tumors (11 located in the right colon, 15 in the left, and 6 in the rectum). The predominant point mutation was KRAS G12D (14.29%, n = 10), which was more frequent in early-stage tumors (I-IIA, n = 7). In agreement with pyrosequencing results, the KRAS G12D mutation was detected by ddPCR in FFPE tumor-derived DNA, and only a residual number of mutated copies was found in WT controls. The KRAS G12D mutation was also detected in stool-derived DNA in 80% of all fecal samples from CRC patients with this point mutation.CONCLUSIONddPCR is a reliable and sensitive method to analyze KRAS G12D mutation in stool-derived DNA from CRC patients, especially at early stages. This non-invasive approach is potentially applicable to other relevant biomarkers for CRC management.展开更多
This study was conducted to examine the responses of earthworms to soil organic matter and litter at different decomposition stages and their contributions in litter decomposition processes in southern subtropical are...This study was conducted to examine the responses of earthworms to soil organic matter and litter at different decomposition stages and their contributions in litter decomposition processes in southern subtropical areas of China. Two plantations were selected as the study sites: Site I was dominated by the exotic endogeic earthworm species Ocnerodrilus occidentalis; Site II was dominated by epigeic species Amynthas corticis. After the fallen litter and earthworms were removed or expelled, four treatments were set up as: reserving the top soil (0–5 cm, equal to H layer) (H), removing the top soil and adding fresh litter (Le), removing the top soil and adding semi-decomposed litter (Li), and a control with no top soil nor any litter (CK). Five randomized blocks that were enclosed with nylon nets on the top were set up in each site, and then the four treatments were arranged randomly in each block. After 2–3 months, earthworms were collected using the formalin method. The results showed that Ocnerodrilus occidentalis preferred Treatment H though it was found in Treatments Le and Li as well; Amynthas corticis preferred Treatment Li though sometimes it also appeared in Treatment H; and Amynthas sp., another epigeic species, was mainly present under Treatment Le and only appeared in Treatment H occasionally. These findings confirmed that earthworm species belonging to different ecological groups had different responses to organic matter at different decomposition stages. The impacts of earthworm communities dominated by O. occidentalis mainly appeared at the later periods of litter decomposition.展开更多
A linear forest is a forest whose components are paths. The linear arboricity la (G) of a graph G is the minimum number of linear forests which partition the edge set E(G) of G. The Cartesian product G□H of two g...A linear forest is a forest whose components are paths. The linear arboricity la (G) of a graph G is the minimum number of linear forests which partition the edge set E(G) of G. The Cartesian product G□H of two graphs G and H is defined as the graph with vertex set V(G□H) = {(u, v)| u ∈V(G), v∈V(H) } and edge set E(G□H) = { ( u, x) ( v, Y)|u=v and xy∈E(H), or uv∈E(G) and x=y}. Let Pm and Cm,, respectively, denote the path and cycle on m vertices and K, denote the complete graph on n vertices. It is proved that (Km□Pm)=[n+1/2]for m≥2,la(Km□Cm)=[n+2/2],and la(Km□Km)=[n+m-1/2]. The methods to decompose these graphs into linear forests are given in the proofs. Furthermore, the linear arboricity conjecture is true for these classes of graphs.展开更多
Acute toxicities of potassium permanganate, formalin, and Lugol’s iodine solution to a commonly occurred marine ciliate Pleuronema coronatum (Ciliophora, Scuticociliatida) were measured. Linear regression analysis of...Acute toxicities of potassium permanganate, formalin, and Lugol’s iodine solution to a commonly occurred marine ciliate Pleuronema coronatum (Ciliophora, Scuticociliatida) were measured. Linear regression analysis of the results highlighted the close relationships between doses of the medicines and mortalities of the organisms, thus providing a capability to predict toxicity effects from the dose. Toxic effects of the medicines on the ciliates were described in the present paper, and the median lethal concentrations (LC 50 values) were given. Results of measurements indicated that 2 h-LC 50 and 12 h-LC 50 values of formalin on P. coronatum were 59.00×10 -6 and 43.57×10 -6, while those of Lugol’s solutions were 90.13 and 67.84×10 -6 respectively. The tolerance of P. coronatum to formalin is apparently lower than that to Lugol’s iodine solution and potassium permanganate is a suitable medicine to kill ciliates in short time.展开更多
Fixatives are traditionally used in marine ecosystem research. The bias introduced by fixatives on.the dimensions of plankton cells may lead to an overestimation or underestimation of the carbon biomass. To determine ...Fixatives are traditionally used in marine ecosystem research. The bias introduced by fixatives on.the dimensions of plankton cells may lead to an overestimation or underestimation of the carbon biomass. To determine the impact of traditional fixatives on dinoflagellates during short- and long-term fixation, we analyzed the degree of change in three bloom-forming dinoflagellates (Prorocentrum rnicans, Scrippsiella trochoidea and Nocfiluca scintillans) brought about by Lugol's iodine solution (hereafter Lugol's) and formalin. The fixation effects were species-specific. P. micans cell volume showed no significant change following long-term preservation, and S. trochoidea swelled by approximately 8.06% in Lugol's and by 20.97% in formalin as a percentage of the live cell volume, respectively. N. scintillans shrank significantly in both fixatives. The volume change due to formalin in N. scintillans was not concentration-dependent, whereas the volume shrinkage ofN. scintillans cells fixed with Lugol's at a concentration of 2% was nearly six-fold that in cells fixed with Lugol's at a concentration of 0.6%-0.8%. To better estimate the volume of N. scintillans fixed in formalin at a concentration of 5%, we suggest that the conversion relationship was as follows: volume of live cell=volume of intact fixed cell/0.61. Apart from size change, damage induced by fixatives on N. scintillans was obvious. Lugol's is not a suitable fixative for N. scintillans due to high frequency of broken cells. Accurate carbon biomass estimate ofN. scintillans should be performed on live samples. These findings help to improve the estimate of phytoplankton cell volume and carbon biomass in marine ecosystem.展开更多
The exchange bias (EB) of the ferromagnetic (FM)/antiferromagnetic (AFM) bilayers in a compensated case is studied by use of the many-body Green's function method of quantum statistical theory. The so-called co...The exchange bias (EB) of the ferromagnetic (FM)/antiferromagnetic (AFM) bilayers in a compensated case is studied by use of the many-body Green's function method of quantum statistical theory. The so-called compensated case is that there is no net magnetization on the AFM side of the interface. Our conclusion is that the EB in this case is primarily from the asymmetry of the interracial exchange coupling strengths between the FM and the two sublattices of the AFM. The effects of the layer thickness, temperature and the interracial coupling strength oi2 the exchange bias HE are investigated. The dependence of HE on the FM layer thickness and temperature is qualitatively in agreement with experimental results. HE is nearly inversely proportional to FM thickness. When temperature varies, both HE and He decrease with temperature increasing. The anisotropy of the FM layer only slightly influence He, but does not influence HE.展开更多
The paper provides an overview of geometric solutions of marking all types of serpentine by the method of internal circular curve in designing forest roads directly in the field. The main objective of presenting this ...The paper provides an overview of geometric solutions of marking all types of serpentine by the method of internal circular curve in designing forest roads directly in the field. The main objective of presenting this original method for marking all serpentine types in one place is to show similarities and differences in marking different types of serpentine, and identify opportunities for further research of this type. The method is based on the establishment of the minimum number of elements necessary to mark the serpentine on the forest roads and other budget elements and their design in the field. By using this method, construction errors or the number of attempts of serpentine marking are reduced, which increases the effects of design compared to the ones reached by the previous method of marking the serpentine on forest roads.展开更多
基金The National Natural Science Foundation of China(30700065)the Program for Fostering Young Talents of Kunming Institute of Zoology,the Chinese Academy of Sciences(0706571141)~~
文摘In order to evaluate the phylogenetic position and validity of Rana altaica,we investigated the phylogeny of brown frogs in Eurasia by Bayesian Inference and Maximum Parsimony analyses of a fragment from the mitochondrial DNA gene Cytochrome b.Both analyses resolved R.altaica as nesting deeply within R.arvalis.Most samples of the nominal R.altaica from the Altai region and specimens from Central Siberia shared a haplotype with R.arvalis based on the network analysis.The matrilineal relationships suggested that R.altaica should be considered as a junior synonym of R.arvalis.Furthermore,our study suggested that the species group division of Chinese brown frogs should be re-evaluated within a phylogenetic context.
文摘Aim To study the effects of tetrodotoxin (TTX) combined with acetylsalicylic acid (ASA) on nociceptive stimulus in mice. Methods To assess the antinociceptive effects of TTX, ASA or TTX plus ASA, the acetic acid-induced abdominal constriction test and formalin pain test were used. Results TTX (0.5 - 4.0 μg· kg^-1 ) or ASA (25 - 200 mg· kg^-1 ) im produced a significant inhibition of acetic acid-induced abdominal constriction. The median inhibitory doses (ID508) were 2.1 μg· kg^-1 for TTX( and 64 mg· kg^-1 for ASA. TTX and ASA also showed a dose-dependent inhibition of the second phase response in the formalin pain model, the ID508, being 2.3μg·kg^-1 and 74.2 mg· kg^-1, respectively. The ihteraction between TTX and ASA was synergistic, as evidenced by the fact that (1) when ASA alone compared with the combination of TTX (0.79 μg · kg^-1 or 0.39μg· kg^-1 ) and ASA, the ID508, of ASA reduced from 64.0 mg· kg^-1 to 5.8 mg· kg^-1 or 12.6 mg· kg^-1, and from 74.2 mg· kg^-1 to 7.4 mg· kg^-1 or 13.0 mg· kg^-1 on tile two models of nociceptive tests, respectively; and that (2) synergism in the analgesic effects was shown by isobiolographic analysis. Conclusion TTX, ASA and the combination of the two drags produce analgesic effects in acetic acid-induced abdominal constriction test and formalin-induced pain test. The interactions between TTX and ASA may be useful in developing novel analgesic agents.
基金Project (No. PSF/Res/P-AU/Bio (246)) supported by Pakistan Sci-ence Foundation (PSF)
文摘In this experiment conducted to study the inactivation dynamics of infectious bursal disease virus (IBDV) by binary ethylenimine (BEI) in comparison with formalin, IBDV was isolated from the bursa of infected chickens and its confirmation was done by agar gel precipitation test. Viral suspensions were subjected to inactivation with BEI and formalin for pre-set time in- tervals. BEI was employed at concentrations of 0.001 and 0.002 mol/L while formalin was used at 0.1% and 0.2%. Sampling was done at 6, 12, 24, 36 and 48 h of incubation and samples were tested for their inactivation status in 9-day-old embryonated eggs and 3-week-old broiler chickens. IBDV was completely inactivated by 0.001 and 0.002 mol/L BEI after 36 h of incubation at 37℃, whereas formalin at 0. 1% and 0.2% concentrations inactivated IBDV in 24 h.
文摘The article presents research findings related to recreational use of forests located in protected mountainous areas with forestage of over 80%. The study was designed to identify recreational potential of the Carpathian national parks (Bieszczady National Park, Bahia G6ra National Park, Goree National Park and Magura National Park; southern Poland) and to compare these findings with the actual number of visitors. The information received on the recreational potential of parks is important from the point of view of protection of natural resources and the financial situation of the parks. The calculated ratio may be an effective tool of management for park administration, that allows to reconcile statutory social and protective functions of national parks. The study determined the recreational potential of the forests with the use of recreational valorisation method designed for areas with varied terrain, and the evaluated factors included the stands of trees with their habitat and land relief. The permissible number of national park visitors, expressed as man- hour/ha/year ranges from 19.31 in Bieszczady National Park (BG: 19~ 35' E, 49~ 35' N) to 32.06 in in Bieszczady National Park (B: 22~ 40' E, 49~ lo' N). In 3 out of 4 investigated parks, Magura National Park (M: 21025' E, 49~ 30' N), Gorce National Park (G: 20~ lo' E, 49~ 35' N), B) recreation carrying capacity was not exceeded, whether or not the strictly protected area is taken into account. Only in BG was the recreation carrying capacity exceeded by nearly 24%, or by 85% if the strictly protected area isexcluded from tourism-related exploitation. The presented procedure for monitoring access to mountain forests in national parks, from the viewpoint of natural resources conservation, can be applied in other mountainous areas covered with forests and exposed to tourist and recreational traffic, and in forests facing particular risk of recreational damage, e.g. in urban and suburban forests growing in areas with varied orography.
文摘Alverine dtrate is a commonly used smooth muscle relaxant agent.A MEDLINE search on January 2004 revealed only 1 report implicating the hepatotoxicity of this agent.A 34- year-old woman was investigated because of the finding of elevated liver function tests on biochemical screening.Other etiologies of hepatitis were appropriately ruled out and elevated enzymes were ascribed to alverine citrate treatment. Although alverine citrate hepatotoxicity was related to an immune mechanism in the first case,several features such as absence of predictable dose-dependent toxicity of alverine citrate in a previous study and absence of hypersensitivity manifestations in our patient are suggestive of a metabolic type of idiosyncratic toxicity.
文摘Livelihood of the people in Nepal hills depends much upon forest resources in addition to farming as forest plays a critical role in the well being of the farming households where access to alternative sources, such as energy for cooking, nutrition for animals, materials for fertilizer and constructing materials for shelter, are limited. Thus, the well being of the people in the hills is directly affected by the management of these forest resources. This issue was addressed in this paper by examining the forest resource management practices and its effect on well being of rural people in two different stages in a village lying in the steep hill of Mahabharat Range in the southern hills of Kathmandu valley, Lalitpur District. The main ethnic/caste groups in the village are Brahmin/Chhetri (high Hindu caste), Magar/Tamang (Tibeto Burmans) and Kami (occupational caste: cobbler). Currently there are four community forest users groups, with mixed ethnic membership, organized to manage the forest resources. The endowments, weak institutional settings, before 1990 helped the Bhramins, Magars and Tamangs to get access into the private forest endowment, which made them easy to get access to the forest resources, mainly fuel wood, fodder and timber in 1990 and enhanced their well beings. But the socially backward Kami could not get benefit from the institutions that existed during that time and had less chance to enhance their well beings. After the set up of different endowments during late 1990s, i.e., hand over of forest management to usersgroupsin line with the concept of community forest, environment to use the forest resources became better for all the groups, along with the management of the forest. This enhanced the well beings of all the groups in the study village. However, the ability of Kami to use the forest resources to enhance their well beings was still lacking behind. The reason was partially due to the difference in endowments carried over from the endowments before 1990, and partly due to their occupational work and location of their settlements.
基金Supported by“Fondo de Investigaciones Sanitarias(FIS)-FEDER”,Ministry of Health,Spain,No.PI13/01924 to García-Olmo DRETIC Program of ISCIII-FEDER,No.RD12/0019/0035 to Olmedillas-López S
文摘AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients with stage I-IV CRC diagnosed by preoperative biopsy. KRAS mutational status was determined by pyrosequencing analysis of DNA obtained from formalin-fixed paraffin-embedded (FFPE) tumor tissues. The KRAS G12D mutation was then analyzed by ddPCR in FFPE tumors and stool-derived DNA from patients with this point mutation. Wild-type (WT) tumors, as determined by pyrosequencing, were included as controls; analysis of FFPE tissue and stool-derived DNA by ddPCR was performed for these patients as well.RESULTSAmong the total 70 patients included, KRAS mutations were detected by pyrosequencing in 32 (45.71%), whereas 38 (54.29%) had WT tumors. The frequency of KRAS mutations was higher in left-sided tumors (11 located in the right colon, 15 in the left, and 6 in the rectum). The predominant point mutation was KRAS G12D (14.29%, n = 10), which was more frequent in early-stage tumors (I-IIA, n = 7). In agreement with pyrosequencing results, the KRAS G12D mutation was detected by ddPCR in FFPE tumor-derived DNA, and only a residual number of mutated copies was found in WT controls. The KRAS G12D mutation was also detected in stool-derived DNA in 80% of all fecal samples from CRC patients with this point mutation.CONCLUSIONddPCR is a reliable and sensitive method to analyze KRAS G12D mutation in stool-derived DNA from CRC patients, especially at early stages. This non-invasive approach is potentially applicable to other relevant biomarkers for CRC management.
基金Project supported by the National Natural Science Foundation of China (No.39970140)the Department of Science andTechnology of Guangdong Province, Chinathe Open Foundation of Heshan Hilly Land Interdisciplinary Experimental Station of the Chinese Academy of Sciences (CAS), and the 100 Talents Program of CAS.
文摘This study was conducted to examine the responses of earthworms to soil organic matter and litter at different decomposition stages and their contributions in litter decomposition processes in southern subtropical areas of China. Two plantations were selected as the study sites: Site I was dominated by the exotic endogeic earthworm species Ocnerodrilus occidentalis; Site II was dominated by epigeic species Amynthas corticis. After the fallen litter and earthworms were removed or expelled, four treatments were set up as: reserving the top soil (0–5 cm, equal to H layer) (H), removing the top soil and adding fresh litter (Le), removing the top soil and adding semi-decomposed litter (Li), and a control with no top soil nor any litter (CK). Five randomized blocks that were enclosed with nylon nets on the top were set up in each site, and then the four treatments were arranged randomly in each block. After 2–3 months, earthworms were collected using the formalin method. The results showed that Ocnerodrilus occidentalis preferred Treatment H though it was found in Treatments Le and Li as well; Amynthas corticis preferred Treatment Li though sometimes it also appeared in Treatment H; and Amynthas sp., another epigeic species, was mainly present under Treatment Le and only appeared in Treatment H occasionally. These findings confirmed that earthworm species belonging to different ecological groups had different responses to organic matter at different decomposition stages. The impacts of earthworm communities dominated by O. occidentalis mainly appeared at the later periods of litter decomposition.
基金The National Natural Science Foundation of China(No.10971025)
文摘A linear forest is a forest whose components are paths. The linear arboricity la (G) of a graph G is the minimum number of linear forests which partition the edge set E(G) of G. The Cartesian product G□H of two graphs G and H is defined as the graph with vertex set V(G□H) = {(u, v)| u ∈V(G), v∈V(H) } and edge set E(G□H) = { ( u, x) ( v, Y)|u=v and xy∈E(H), or uv∈E(G) and x=y}. Let Pm and Cm,, respectively, denote the path and cycle on m vertices and K, denote the complete graph on n vertices. It is proved that (Km□Pm)=[n+1/2]for m≥2,la(Km□Cm)=[n+2/2],and la(Km□Km)=[n+m-1/2]. The methods to decompose these graphs into linear forests are given in the proofs. Furthermore, the linear arboricity conjecture is true for these classes of graphs.
基金This work is supported by the Natural Science Foundation of China(No.40206021).
文摘Acute toxicities of potassium permanganate, formalin, and Lugol’s iodine solution to a commonly occurred marine ciliate Pleuronema coronatum (Ciliophora, Scuticociliatida) were measured. Linear regression analysis of the results highlighted the close relationships between doses of the medicines and mortalities of the organisms, thus providing a capability to predict toxicity effects from the dose. Toxic effects of the medicines on the ciliates were described in the present paper, and the median lethal concentrations (LC 50 values) were given. Results of measurements indicated that 2 h-LC 50 and 12 h-LC 50 values of formalin on P. coronatum were 59.00×10 -6 and 43.57×10 -6, while those of Lugol’s solutions were 90.13 and 67.84×10 -6 respectively. The tolerance of P. coronatum to formalin is apparently lower than that to Lugol’s iodine solution and potassium permanganate is a suitable medicine to kill ciliates in short time.
基金Supported by the National Basic Research Program of China(973Program)(No.2014CB441504)the"Strategic Priority Research ProgramWestern Pacific Ocean System"of the Chinese Academy of Sciences(No.XDA11030204)+1 种基金the Key Program of the National Natural Science Foundation of China(No.41230963)the NSFC-Shandong Province Joint Fund Project(No.U1406403)
文摘Fixatives are traditionally used in marine ecosystem research. The bias introduced by fixatives on.the dimensions of plankton cells may lead to an overestimation or underestimation of the carbon biomass. To determine the impact of traditional fixatives on dinoflagellates during short- and long-term fixation, we analyzed the degree of change in three bloom-forming dinoflagellates (Prorocentrum rnicans, Scrippsiella trochoidea and Nocfiluca scintillans) brought about by Lugol's iodine solution (hereafter Lugol's) and formalin. The fixation effects were species-specific. P. micans cell volume showed no significant change following long-term preservation, and S. trochoidea swelled by approximately 8.06% in Lugol's and by 20.97% in formalin as a percentage of the live cell volume, respectively. N. scintillans shrank significantly in both fixatives. The volume change due to formalin in N. scintillans was not concentration-dependent, whereas the volume shrinkage ofN. scintillans cells fixed with Lugol's at a concentration of 2% was nearly six-fold that in cells fixed with Lugol's at a concentration of 0.6%-0.8%. To better estimate the volume of N. scintillans fixed in formalin at a concentration of 5%, we suggest that the conversion relationship was as follows: volume of live cell=volume of intact fixed cell/0.61. Apart from size change, damage induced by fixatives on N. scintillans was obvious. Lugol's is not a suitable fixative for N. scintillans due to high frequency of broken cells. Accurate carbon biomass estimate ofN. scintillans should be performed on live samples. These findings help to improve the estimate of phytoplankton cell volume and carbon biomass in marine ecosystem.
基金supported by National Natural Science Foundation of China under Grant Nos.10574121,10874160,and 10025420the‘111’Project of the Ministry of Education and the Chinese Academy of Sciences
文摘The exchange bias (EB) of the ferromagnetic (FM)/antiferromagnetic (AFM) bilayers in a compensated case is studied by use of the many-body Green's function method of quantum statistical theory. The so-called compensated case is that there is no net magnetization on the AFM side of the interface. Our conclusion is that the EB in this case is primarily from the asymmetry of the interracial exchange coupling strengths between the FM and the two sublattices of the AFM. The effects of the layer thickness, temperature and the interracial coupling strength oi2 the exchange bias HE are investigated. The dependence of HE on the FM layer thickness and temperature is qualitatively in agreement with experimental results. HE is nearly inversely proportional to FM thickness. When temperature varies, both HE and He decrease with temperature increasing. The anisotropy of the FM layer only slightly influence He, but does not influence HE.
文摘The paper provides an overview of geometric solutions of marking all types of serpentine by the method of internal circular curve in designing forest roads directly in the field. The main objective of presenting this original method for marking all serpentine types in one place is to show similarities and differences in marking different types of serpentine, and identify opportunities for further research of this type. The method is based on the establishment of the minimum number of elements necessary to mark the serpentine on the forest roads and other budget elements and their design in the field. By using this method, construction errors or the number of attempts of serpentine marking are reduced, which increases the effects of design compared to the ones reached by the previous method of marking the serpentine on forest roads.