In the last two decades, great efforts have been made in the treatment of metastatic colorectal cancer(m CRC) due to the approval of new target agents for cytotoxic drugs. Unfortunately, a large percentage of patients...In the last two decades, great efforts have been made in the treatment of metastatic colorectal cancer(m CRC) due to the approval of new target agents for cytotoxic drugs. Unfortunately, a large percentage of patients present with metastasis at the time of diagnosis or relapse after a few months. The complex molecular heterogeneity of this disease is not completely understood; to date, there is a lack of predictive biomarkers that can be used to select subsets of patients who may respond to target drugs. Only the RAS-mutation status is used to predict resistance to anti-epidermal growth factor receptor agents in patients with m CRC. In this review, we describe approved targeted therapies for the management of metastatic m CRC and discuss new candidate targets on the horizon.展开更多
Objective： We conducted a prospective phase II trial of single-agent salvage chemotherapy with docetaxel in patients with advanced non-small cell lung cancer （NSCLC） after failure of chemotherapy and gefitinib to a...Objective： We conducted a prospective phase II trial of single-agent salvage chemotherapy with docetaxel in patients with advanced non-small cell lung cancer （NSCLC） after failure of chemotherapy and gefitinib to assess the efficacy and toxicity of docetaxel in this setting. Methods： Patients with histologically confirmed NSCLC who were failure of chemotherapy and gefitinib were given docetaxel 75 mg/m^2 intravenously for 30 rain every 3 weeks until the toxicity was unacceptable or disease progressed. The response evaluation criteria in solid tumors （RECIST） guidelines were used for the evaluation of an- titumor activity. Toxicity was graded according to the National Cancer Institute Common Toxicity Criteria version 2.0. Results： In total, 31 patients were enrolled in this phase II trial between February 2004 and December 2006, and 84 cycles （average 2.7 cycles） were given. We observed 4 partial responses （PRs） and 10 stable disease （SD） states in 31 eligible patients. The objective response rate was 12.9%, and the disease control rate was 45.2%. The median survival time （MST） was 10 months （95% CI, 5.05-15.08 months）. The 1-year survival rate was 40.6%. The most common toxicities were neutropenia, anemia, and peripheral neuropathy that occurred as follows： 45% of the patients experienced grade 3 or 4 neutropenia, 29% experienced grade 3 anemia, and 25.8% had grade 3 peripheral neuropathy. No patient terminated docetaxel chemotherapy due to toxicity. Conclusion： Docetaxel is beneficial as salvage chemotherapy in patients with advanced NSCLC after failure of cytotoxic agents and gefitinib.展开更多
An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm dec...An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm decreases if the global environment is represented by regular grids with all of them at the highest resolution. The framed quadtree data structure is able to more efficiently represent the environment. When planning the path, the dynamic object is expressed instead as several static objects which are used by the path planner to update the path. By taking account of the characteristics of the framed quadtree, objects can be projected on the frame nodes to increase the precision of the path. Analysis and simulations showed the proposed planner could increase efficiency while improving the ability of the AUV to follow an object.展开更多
Objective： To report the occurrence, management and outcome ot late-onset traumauc aemscence ana dislocation of laser assisted in situ keratomileusis （LASIK） flaps. Treatment and Results： One patient occurred late...Objective： To report the occurrence, management and outcome ot late-onset traumauc aemscence ana dislocation of laser assisted in situ keratomileusis （LASIK） flaps. Treatment and Results： One patient occurred late-onset LASIK corneal flap dislocation after ocular trauma 7days after surgery. The flap was lifted, stretched, and repositioned after irrigation and scraping of the stromal bed and the underside of the flap. A bandage contact lens was placed, and topical antibiotic and corticosteroids were given postoperatively. The dislocated corneal flap was successfully repositioned in the case. The dislocated flap was repositioned 7 days after the trauma, and the patient recovered his uncorrected visual acuity （UCVA） of 10/20, 20/20 day 1 and day 20 after the procedure, of 20/20 20 days later and had a well-positioned flap with a clear interface. Diffuse lamellar keratitis developed in the patients that resolved with the use of topical corticosteroids. Conclusion： Laser in situ keratomileusis corneal flaps are vulnerable to traumatic dehiscence and dislocation, which should be pay more attention to it for us.展开更多
Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targe...Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targeting ability. Methods: The synthetic polypeptides CR16 for binding FGF receptors was conjugated to PEI and the characters of the polypeptides in-cluding DNA condensing and particle size were determined. Enhanced efficiency and the targeting specificity of the synthesized vector were investigated in vitro and in vivo. Results: The polypeptides were successfully coupled to PEI. The new vectors PEI-CR16 could efficiently condense pDNA into particles with around 200 nm diameter. The PEI-CR16/pDNA polyplexes showed significantly greater transgene activity than PEI/pDNA in FGF receptors positive tumor cells in vitro and in vivo gene transfer, while no difference was observed in FGF receptors negative tumor cells. The enhanced transfection efficiency of PEI-CR16 could be blocked by excess free polypeptides. Conclusion: The synthesized vector could improve the efficiency of gene transfer and targeting specificity in FGF receptors positive cells. The vector had good prospect for use in cancer gene therapy.展开更多
This paper analyses the system of artistic and ideological conditioning that architects were subject to during the Portuguese fascism, the so-called ＂New State＂, the longest western European dictatorship of the prev...This paper analyses the system of artistic and ideological conditioning that architects were subject to during the Portuguese fascism, the so-called ＂New State＂, the longest western European dictatorship of the previous century, that lasted from 1933 to 1974, under the uninterrupted leadership of Ant6nio de Oliveira Salazar until 1968. After a concise exposition of the importance of a major public work campaign to the regime affirmation as well as the aesthetic discourse promoted in its architecture, the standard course of a building project evaluation will be described. Crossing varied legislation and taking into consideration the results of a thorough examination to more than one hundred processes of architectural plans approval, the interaction of the various decision-making bodies will illustrate the existence of an efficient apparatus which progressively depurate designs. Prevention and repression of artistic deviation will be demonstrated. Furthermore, the development and importance of self-censorship will be highlighted. Secondly, a characterization of the atmosphere of ideological surveillance and dissident＇s oppression will be provided. Architects＇ participation in opposition＇s initiatives and strategies will be portrayed. As a conclusion, New State practice of a negotiation and inclusion （both artistic and ideological） tactic in the architectural field will be underlined.展开更多
This research shows the current status and the future prospects of green financing in Korea. Green financing is currently on the initial stage in Korea, just like the green growth policy. Thus, banks are contextually ...This research shows the current status and the future prospects of green financing in Korea. Green financing is currently on the initial stage in Korea, just like the green growth policy. Thus, banks are contextually not willing to invest or loan in the green technology or industry for profitability, because the high uncertainty （risk） exists and because Korean people have little concern on green financing, though they have recognized the necessity of green growth. Therefore, the reinforcement of government＇s role is suggested in this research. The public financial agencies are now very important in popularizing the green financing in Korea, and the most effective policy will be the credit guarantee for green technologies or companies provided by public agencies, as shown in the financing policy for the small and middle enterprises. Regarding public efforts, banks should try to perform green financing for both their own profitability and social benefit together with the step-by-step approach, according to the growth stage of green industry and green financing.展开更多
Land use change is one of the major factors that affect soil organic carbon （SOC） variation and global carbon balance. However, the effects of land use change on SOC are always variable. In this study, using a serie...Land use change is one of the major factors that affect soil organic carbon （SOC） variation and global carbon balance. However, the effects of land use change on SOC are always variable. In this study, using a series of paired-field experiments, we estimated the effects of revegetation types and environmental conditions on SOC stock and vertical distribution after replacement of cropland with poplar （Populus tomentosa） and korshinsk peashrub （Caragana korshinskt＇i） in three climate regions （Chifeng City, Fengning City and Datong City of the ＇Beijing-Tianjin Sandstorm Source Control＇ （BTSSC） program area. The results show that SOC sequestration rate ranges from 0.15 Mg/（ha-yr） to 3.76 Mg/（ha-yr） in the soil layer of 0-100 cm in early stage after cropland afforestation in the BTSSC program area. The SOC accumulation rates are the highest in Fengning for both the two vegetation types. Compared to C. korshinskii, P tomentosa has greater effects on SOC accumulation in the three climate regions, but significantly greater effect only appears in Datong. The SOC density increases by 20%-111% and 15%-59% for P. tomentosa and 9%-63% and 0-73% for C. korshinskii in the 0-20 cm and 20-100 cm soil layers, respectively. Our results indicate that cropland afforestation not only affects SOC stock in the topsoil, but also has some effects on subsoil carbon. However, the effect of cropland afforestation on SOC accumulation varied with climate regions and revegetation types. Considering the large area of revegetation and relatively high SOC accumulation rate, SOC sequestration in the BTSSC program should contribute significantly to decrease the CO2 concentration in the atmosphere.展开更多
We systematically reviewed the clinical trials which recruited antioxidants in the therapy of pancreatitis and evaluated whether antioxidants improve the outcome of patients with pancreatitis. Electronic bibliographic...We systematically reviewed the clinical trials which recruited antioxidants in the therapy of pancreatitis and evaluated whether antioxidants improve the outcome of patients with pancreatitis. Electronic bibliographic databases were searched for any studies which investigated the use of antioxidants in the management of acute pancreatitis （AP） or chronic pancreatitis （CP） and in the prevention of post-endoscopic retrograde cholangio-pancreatography （post-ERCP） pancreatitis （PEP） up to February 2009. Twenty-two randomized, placebo-controlled, clinical trials met our criteria and were included in the review. Except for a cocktail of antioxidants which showed improvement in outcomes in three different clinical trials, the results of the administration of other antioxidants in both AP and CP clinical trials were incongruent and heterogeneous.Furthermore, antioxidant therapy including allopurinol and N-acetylcysteine failed to prevent the onset of PEP in almost all trials. In conclusion, the present data do not support a benefit of antioxidant therapy alone or in combination with conventional therapy in the management of AP, CP or PER Further double blind, randomized, placebo-controlled clinical trials with large sample size need to be conducted.展开更多
With the emergence of the Cultural School in the 1990s, researchers began to deem that translation is inevitably associated with political tendencies and aspirations of social groups, and the relationship between sour...With the emergence of the Cultural School in the 1990s, researchers began to deem that translation is inevitably associated with political tendencies and aspirations of social groups, and the relationship between source language and target language has never gone beyond politics and are always entangled with power. From political perspective, this thesis will take the popularity of Yu Hua’s works in US into account to analyze and explore how cultural soft power, has impacts on translation activities, especially translation direction and source text selection.展开更多
Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of whi...Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of which had started or that had been assessed and approved. Based on a comparative analysis of the limits of ecological restoration in different ecologically vulnerable areas from the perspective of space, as well as an examination of ecological sensitivity factors in the ecosystems surrounding airport construction projects, suggestions concerning key ecological control techniques to be employed in airport construction projects in different ecologically vulnerable areas are put forward. The results showed that the airport construction projects recently approved by the Ministry of Water Resources and the Environmental Protection Agency are mainly distributed in the ecologically vulnerable areas of the Red Soil Hilly Area in southern China, the Karst Rocky Desertification Area in southwest China, the Agro-pastoral Ecotone in the southwestern mountain region, and the Desert-Oasis Connecting Belt in northwest China. The airport construction projects in the southwest mountain area, the hilly areas of southern China, and in the Qinghai-Tibetan Plateau are mainly based on the ecological technologies of slope protection, interception and drainage management, and vegetation restoration, respectively. In the arid and semi-arid areas, the ecological control technology employed in airport construction is mainly the rational utilization of water resources and reduction or mitigation of the effects of sandstorms. This study aims to serve as basis for soil and water conservation plans in airport construction projects and accelerate ecosystem restoration within the vicinity of airport construction sites.展开更多
In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex ...In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are het-erozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hym-enopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control.展开更多
Natural products have been extensively used to treat diseases throughout human history. These are mainly because natural products normally target biological macromolecules selectively. Target identification could help...Natural products have been extensively used to treat diseases throughout human history. These are mainly because natural products normally target biological macromolecules selectively. Target identification could help us to develop new therapeutic agents and discover new biological pathways underlying human diseases. Herein, we highlight some recent examples of using natural products and their derivatives as chemical probes to identify the molecular targets and elucidate mode of action.展开更多
文摘In the last two decades, great efforts have been made in the treatment of metastatic colorectal cancer(m CRC) due to the approval of new target agents for cytotoxic drugs. Unfortunately, a large percentage of patients present with metastasis at the time of diagnosis or relapse after a few months. The complex molecular heterogeneity of this disease is not completely understood; to date, there is a lack of predictive biomarkers that can be used to select subsets of patients who may respond to target drugs. Only the RAS-mutation status is used to predict resistance to anti-epidermal growth factor receptor agents in patients with m CRC. In this review, we describe approved targeted therapies for the management of metastatic m CRC and discuss new candidate targets on the horizon.
基金the Chinese State Key Program for Basic Research (No. 2002BA711A08)the Foundation of Guangzhou Science and Technology Bureau (No. 2001-Z-044-01)the Guangdong Provincial Department of Health, China (No. 2004-199- 25)
文摘Objective： We conducted a prospective phase II trial of single-agent salvage chemotherapy with docetaxel in patients with advanced non-small cell lung cancer （NSCLC） after failure of chemotherapy and gefitinib to assess the efficacy and toxicity of docetaxel in this setting. Methods： Patients with histologically confirmed NSCLC who were failure of chemotherapy and gefitinib were given docetaxel 75 mg/m^2 intravenously for 30 rain every 3 weeks until the toxicity was unacceptable or disease progressed. The response evaluation criteria in solid tumors （RECIST） guidelines were used for the evaluation of an- titumor activity. Toxicity was graded according to the National Cancer Institute Common Toxicity Criteria version 2.0. Results： In total, 31 patients were enrolled in this phase II trial between February 2004 and December 2006, and 84 cycles （average 2.7 cycles） were given. We observed 4 partial responses （PRs） and 10 stable disease （SD） states in 31 eligible patients. The objective response rate was 12.9%, and the disease control rate was 45.2%. The median survival time （MST） was 10 months （95% CI, 5.05-15.08 months）. The 1-year survival rate was 40.6%. The most common toxicities were neutropenia, anemia, and peripheral neuropathy that occurred as follows： 45% of the patients experienced grade 3 or 4 neutropenia, 29% experienced grade 3 anemia, and 25.8% had grade 3 peripheral neuropathy. No patient terminated docetaxel chemotherapy due to toxicity. Conclusion： Docetaxel is beneficial as salvage chemotherapy in patients with advanced NSCLC after failure of cytotoxic agents and gefitinib.
基金Supported by the National Natural Science Foundation of China under Grant No. 60875071
文摘An autonomous underwater vehicle (AUV) must use an algorithm to plan its path to distant, mobile offshore objects. Because of the uneven distribution of obstacles in the real world, the efficiency of the algorithm decreases if the global environment is represented by regular grids with all of them at the highest resolution. The framed quadtree data structure is able to more efficiently represent the environment. When planning the path, the dynamic object is expressed instead as several static objects which are used by the path planner to update the path. By taking account of the characteristics of the framed quadtree, objects can be projected on the frame nodes to increase the precision of the path. Analysis and simulations showed the proposed planner could increase efficiency while improving the ability of the AUV to follow an object.
文摘Objective： To report the occurrence, management and outcome ot late-onset traumauc aemscence ana dislocation of laser assisted in situ keratomileusis （LASIK） flaps. Treatment and Results： One patient occurred late-onset LASIK corneal flap dislocation after ocular trauma 7days after surgery. The flap was lifted, stretched, and repositioned after irrigation and scraping of the stromal bed and the underside of the flap. A bandage contact lens was placed, and topical antibiotic and corticosteroids were given postoperatively. The dislocated corneal flap was successfully repositioned in the case. The dislocated flap was repositioned 7 days after the trauma, and the patient recovered his uncorrected visual acuity （UCVA） of 10/20, 20/20 day 1 and day 20 after the procedure, of 20/20 20 days later and had a well-positioned flap with a clear interface. Diffuse lamellar keratitis developed in the patients that resolved with the use of topical corticosteroids. Conclusion： Laser in situ keratomileusis corneal flaps are vulnerable to traumatic dehiscence and dislocation, which should be pay more attention to it for us.
基金Project (Nos. 2001AA217071 and 2003AA216041) supported by the Hi-Tech Research and Development Program (863) of China
文摘Objective: To construct a novel kind of nonviral gene delivery vector based on polyethylenimine (PEI) conjugated with polypeptides derived from ligand FGF with high transfection efficiency and according to tumor targeting ability. Methods: The synthetic polypeptides CR16 for binding FGF receptors was conjugated to PEI and the characters of the polypeptides in-cluding DNA condensing and particle size were determined. Enhanced efficiency and the targeting specificity of the synthesized vector were investigated in vitro and in vivo. Results: The polypeptides were successfully coupled to PEI. The new vectors PEI-CR16 could efficiently condense pDNA into particles with around 200 nm diameter. The PEI-CR16/pDNA polyplexes showed significantly greater transgene activity than PEI/pDNA in FGF receptors positive tumor cells in vitro and in vivo gene transfer, while no difference was observed in FGF receptors negative tumor cells. The enhanced transfection efficiency of PEI-CR16 could be blocked by excess free polypeptides. Conclusion: The synthesized vector could improve the efficiency of gene transfer and targeting specificity in FGF receptors positive cells. The vector had good prospect for use in cancer gene therapy.
文摘This paper analyses the system of artistic and ideological conditioning that architects were subject to during the Portuguese fascism, the so-called ＂New State＂, the longest western European dictatorship of the previous century, that lasted from 1933 to 1974, under the uninterrupted leadership of Ant6nio de Oliveira Salazar until 1968. After a concise exposition of the importance of a major public work campaign to the regime affirmation as well as the aesthetic discourse promoted in its architecture, the standard course of a building project evaluation will be described. Crossing varied legislation and taking into consideration the results of a thorough examination to more than one hundred processes of architectural plans approval, the interaction of the various decision-making bodies will illustrate the existence of an efficient apparatus which progressively depurate designs. Prevention and repression of artistic deviation will be demonstrated. Furthermore, the development and importance of self-censorship will be highlighted. Secondly, a characterization of the atmosphere of ideological surveillance and dissident＇s oppression will be provided. Architects＇ participation in opposition＇s initiatives and strategies will be portrayed. As a conclusion, New State practice of a negotiation and inclusion （both artistic and ideological） tactic in the architectural field will be underlined.
文摘This research shows the current status and the future prospects of green financing in Korea. Green financing is currently on the initial stage in Korea, just like the green growth policy. Thus, banks are contextually not willing to invest or loan in the green technology or industry for profitability, because the high uncertainty （risk） exists and because Korean people have little concern on green financing, though they have recognized the necessity of green growth. Therefore, the reinforcement of government＇s role is suggested in this research. The public financial agencies are now very important in popularizing the green financing in Korea, and the most effective policy will be the credit guarantee for green technologies or companies provided by public agencies, as shown in the financing policy for the small and middle enterprises. Regarding public efforts, banks should try to perform green financing for both their own profitability and social benefit together with the step-by-step approach, according to the growth stage of green industry and green financing.
基金Under the auspices of Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA05060600)Knowledge Innovation Programs of Chinese Academy of Sciences(No.KSCX2-EW-J-5)National Key Technology Research and Development Program of China(No.2011BAD31B02)
文摘Land use change is one of the major factors that affect soil organic carbon （SOC） variation and global carbon balance. However, the effects of land use change on SOC are always variable. In this study, using a series of paired-field experiments, we estimated the effects of revegetation types and environmental conditions on SOC stock and vertical distribution after replacement of cropland with poplar （Populus tomentosa） and korshinsk peashrub （Caragana korshinskt＇i） in three climate regions （Chifeng City, Fengning City and Datong City of the ＇Beijing-Tianjin Sandstorm Source Control＇ （BTSSC） program area. The results show that SOC sequestration rate ranges from 0.15 Mg/（ha-yr） to 3.76 Mg/（ha-yr） in the soil layer of 0-100 cm in early stage after cropland afforestation in the BTSSC program area. The SOC accumulation rates are the highest in Fengning for both the two vegetation types. Compared to C. korshinskii, P tomentosa has greater effects on SOC accumulation in the three climate regions, but significantly greater effect only appears in Datong. The SOC density increases by 20%-111% and 15%-59% for P. tomentosa and 9%-63% and 0-73% for C. korshinskii in the 0-20 cm and 20-100 cm soil layers, respectively. Our results indicate that cropland afforestation not only affects SOC stock in the topsoil, but also has some effects on subsoil carbon. However, the effect of cropland afforestation on SOC accumulation varied with climate regions and revegetation types. Considering the large area of revegetation and relatively high SOC accumulation rate, SOC sequestration in the BTSSC program should contribute significantly to decrease the CO2 concentration in the atmosphere.
文摘We systematically reviewed the clinical trials which recruited antioxidants in the therapy of pancreatitis and evaluated whether antioxidants improve the outcome of patients with pancreatitis. Electronic bibliographic databases were searched for any studies which investigated the use of antioxidants in the management of acute pancreatitis （AP） or chronic pancreatitis （CP） and in the prevention of post-endoscopic retrograde cholangio-pancreatography （post-ERCP） pancreatitis （PEP） up to February 2009. Twenty-two randomized, placebo-controlled, clinical trials met our criteria and were included in the review. Except for a cocktail of antioxidants which showed improvement in outcomes in three different clinical trials, the results of the administration of other antioxidants in both AP and CP clinical trials were incongruent and heterogeneous.Furthermore, antioxidant therapy including allopurinol and N-acetylcysteine failed to prevent the onset of PEP in almost all trials. In conclusion, the present data do not support a benefit of antioxidant therapy alone or in combination with conventional therapy in the management of AP, CP or PER Further double blind, randomized, placebo-controlled clinical trials with large sample size need to be conducted.
文摘With the emergence of the Cultural School in the 1990s, researchers began to deem that translation is inevitably associated with political tendencies and aspirations of social groups, and the relationship between source language and target language has never gone beyond politics and are always entangled with power. From political perspective, this thesis will take the popularity of Yu Hua’s works in US into account to analyze and explore how cultural soft power, has impacts on translation activities, especially translation direction and source text selection.
基金The National Key Research and Development Program of China(2016YFC0503704)
文摘Numerous airports have been constructed based on the Twelfth Five-Year Plan for Civil Aviation Development of China. We collected relevant data on the number and distribution of civil airports, the construction of which had started or that had been assessed and approved. Based on a comparative analysis of the limits of ecological restoration in different ecologically vulnerable areas from the perspective of space, as well as an examination of ecological sensitivity factors in the ecosystems surrounding airport construction projects, suggestions concerning key ecological control techniques to be employed in airport construction projects in different ecologically vulnerable areas are put forward. The results showed that the airport construction projects recently approved by the Ministry of Water Resources and the Environmental Protection Agency are mainly distributed in the ecologically vulnerable areas of the Red Soil Hilly Area in southern China, the Karst Rocky Desertification Area in southwest China, the Agro-pastoral Ecotone in the southwestern mountain region, and the Desert-Oasis Connecting Belt in northwest China. The airport construction projects in the southwest mountain area, the hilly areas of southern China, and in the Qinghai-Tibetan Plateau are mainly based on the ecological technologies of slope protection, interception and drainage management, and vegetation restoration, respectively. In the arid and semi-arid areas, the ecological control technology employed in airport construction is mainly the rational utilization of water resources and reduction or mitigation of the effects of sandstorms. This study aims to serve as basis for soil and water conservation plans in airport construction projects and accelerate ecosystem restoration within the vicinity of airport construction sites.
文摘In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are het-erozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hym-enopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control.
基金supported by the National Basic Research Program of China (2015CB856200)the National Natural Science Foundation of China (21472010, 21561142002)
文摘Natural products have been extensively used to treat diseases throughout human history. These are mainly because natural products normally target biological macromolecules selectively. Target identification could help us to develop new therapeutic agents and discover new biological pathways underlying human diseases. Herein, we highlight some recent examples of using natural products and their derivatives as chemical probes to identify the molecular targets and elucidate mode of action.
