The importance of water to our lives cannot be overemphasized as it is the source of all living things. Water scarcity is a concern in many Middle Eastern nations due to war and politics. Many people lose their essenc...The importance of water to our lives cannot be overemphasized as it is the source of all living things. Water scarcity is a concern in many Middle Eastern nations due to war and politics. Many people lose their essence due to actions made by their rulers, such as the Marsh Arabs. Water and biodiversity should be considered, and governments should be held accountable for attaining a more balanced lifestyle and reducing immigrant levels. Many academics have also explored the hydro-immigration of marshland residents. They suffer more hazards due to a lack of money, poor education, and social instability than their colleagues who remain in their own country. Furthermore, they have insufficient health care and have difficulty integrating into the new community. This implies that not all nations that receive such migrants can implement programs to assist the immigrants. This research reveals how wars, hydro-politics, and immigration issues have drastically affected architecture and social structures in the Arab Marshes region, leading to ecological destruction, mass migrations, and cultural loss. Therefore, this work focuses on the need to critically investigate all factors covered within the context of this research.展开更多
Organizations regardless of size can take advantage of the market dynamics brought about by globalization.Supply chain management is crucial for large organizations,especially with regard to the costs,complexity,and r...Organizations regardless of size can take advantage of the market dynamics brought about by globalization.Supply chain management is crucial for large organizations,especially with regard to the costs,complexity,and risks of its large,often global,supply chains.From technology to risk management,learning what it takes to navigate transportation and logistics business management in today’s volatile world is critical.Human migration has accelerated in light of globalization and rapid advances in transportation(particularly aviation)technology.This study investigated the connection between logistics and supply chain management in the age of globalization;reviewed the migration,settlement,and naturalization of Taiwan region of China immigrants along the West Coast of the United States;and theoretically analyzed the forces that have led to the construction of the Taiwan region of China immigrant community.Taiwan region of China immigrants and their settlement are affected by global forces,and factors such as their cross-cultural trade,the characteristics of diasporic communities,and their national identity can provide scholarly and pedagogical insights.展开更多
Immigration relocation of the poor in rural areas is an effective targeted measure to help people out of poverty in the new normal. The structural constraints lie in the heavy pressure of land resources and environmen...Immigration relocation of the poor in rural areas is an effective targeted measure to help people out of poverty in the new normal. The structural constraints lie in the heavy pressure of land resources and environmental carrying capacity, high cost of immigration settlement and delayed counterpart funds, insufficient industrial support and difficulty in living-making. To realize the goal of targeted poverty alleviation, it demands determination and capability from the policy designer, as well the social basis. The effect imposed by the structural constraints to implementation of such policy should be paid adequate attention by public sectors. It is supposed to change the guiding direction of the policy timely and to relieve financial burden of immigration settlement and resource environmental bearing capacity through mechanism of joint efforts from internal and more external support.展开更多
Two sequencing batch reactors（SBRs） were operated for 100 days under aerobic conditions,with one being fed with unsterilized municipal wastewater（USBR）, and the other fed with sterilized municipal wastewater（SSBR...Two sequencing batch reactors（SBRs） were operated for 100 days under aerobic conditions,with one being fed with unsterilized municipal wastewater（USBR）, and the other fed with sterilized municipal wastewater（SSBR）. Respirometric assays and fluorescence in situ hybridization（FISH） results show that active nitrifiers were present in the unsterilized influent municipal wastewater. The maximum ammonia utilization rate（AUR） and nitrite utilization rate（NUR） of the unsterilized influent were 0.32 ± 0.12 mg NH4＋-N/（L·hr） and0.71 ± 0.18 mg NO2--N/（L·hr）. Based on the maximum utilization rates, the estimated seeding intensity for the ammonia oxidizing bacteria（AOB） and nitrite oxidizing bacteria（NOB） of the USBR was 0.08 g AOB/（g AOB·day） and 0.20 g NOB/（g NOB·day） respectively. The fraction of nitrifiers/total bacteria in the influent was 5.35% ± 2.1%, the dominant AOB was Nitrosomonas spp., Nitrosococcus mobilis hybridizated with Nsm156, and the dominant NOB was Nitrospira hybridizated with Ntspa662. The influent nitrifiers potentially seeded the activated sludge of the bioreactor and hence demonstrated a mitigation of the acclimatization times and instability during start-up and early operation. The AUR and NUR in the USBR was 15% and 13% higher than the SSBR respectively during the stable stage, FISH results showed that nitrifiers population especially the Nitrospira in the USBR was higher than that in the SSBR. These results indicate that the natural continuous immigration of nitrifiers from municipal influent streams may have some repercussions on the modeling and design of bioreactors.展开更多
Let(Z_(n))be a branching process with immigration in a random environmentξ,whereξis an independent and identically distributed sequence of random variables.We show asymptotic properties for all the moments of Z_(n) ...Let(Z_(n))be a branching process with immigration in a random environmentξ,whereξis an independent and identically distributed sequence of random variables.We show asymptotic properties for all the moments of Z_(n) and describe the decay rates of the n-step transition probabilities.As applications,a large deviation principle for the sequence log Z_(n) is established,and related large deviations are also studied.展开更多
We are interested in the convergence rates of the submartingale Wn=Z_(n)/Π_(n)to its limit W,where(Π_(n))is the usually used norming sequence and(Z_(n))is a supercritical branching process with immigration(Y_(n))in ...We are interested in the convergence rates of the submartingale Wn=Z_(n)/Π_(n)to its limit W,where(Π_(n))is the usually used norming sequence and(Z_(n))is a supercritical branching process with immigration(Y_(n))in a stationary and ergodic environmentξ.Under suitable conditions,we establish the following central limit theorems and results about the rates of convergence in probability or in law:(i)W-W_(n) with suitable normalization converges to the normal law N(0,1),and similar results also hold for W_(n+k)-W_(n) for each fixed k∈N^(*);(ii)for a branching process with immigration in a finite state random environment,if W_(1) has a finite exponential moment,then so does W,and the decay rate of P(|W-W_(n)|>ε)is supergeometric;(iii)there are normalizing constants an(ξ)(that we calculate explicitly)such that a_(n)(ξ)(W-W_(n))converges in law to a mixture of the Gaussian law.展开更多
T cells play a critical role in immunity to protect against pathogens and malignant cells.T cell immunodeficiency is detrimental,especially when T cell perturbation occurs during severe infection,irradiation,chemother...T cells play a critical role in immunity to protect against pathogens and malignant cells.T cell immunodeficiency is detrimental,especially when T cell perturbation occurs during severe infection,irradiation,chemotherapy,and age-related thymic atrophy.Therefore,strategies that enhance T cell reconstitution provide considerable benefit and warrant intensive investigation.Here,we report the construction of a T cell ablation model in Tg(coro1a:Den NTR)zebrafish via metronidazole administration.The nascent T cells are mainly derived from the hematopoietic cells migrated from the kidney,the functional homolog of bone marrow and the complete recovery time is 6.5 days post-treatment.The cxcr4b gene is upregulated in the responsive hematopoietic cells.Functional interference of CXCR4 via both genetic and chemical manipulations does not greatly affect T lymphopoiesis,but delays T cell regeneration by disrupting hematopoietic migration.In contrast,cxcr4b accelerates the replenishment of hematopoietic cells in the thymus.Consistently,Cxcl12b,a ligand of Cxcr4,is increased in the thymic epithelial cells of the injured animals.Decreased or increased expression of Cxcl12b results in compromised or accelerated T cell recovery,respectively,similar to those observed with Cxcr4b.Taken together,our study reveals a role of CXCR4-CXCL12 signaling in promoting T cell recovery and provides a promising target for the treatment of immunodeficiency due to T cell injury.展开更多
In 1994, the total Chinese population in the United States were 2,017,799 which were 0.8 percent of the total US population. The Chinese population were highly concentrated by regions and among the total population. B...In 1994, the total Chinese population in the United States were 2,017,799 which were 0.8 percent of the total US population. The Chinese population were highly concentrated by regions and among the total population. By states, 42 percent of total Chinese population were found in California, 17 percent in New York. More than 80 percent total Chinese population were concentrated in 9 states. By metropolitan areas, 14.73 percent of total Chinese population were found in Los Angeles and New York respectively. Compared with the total US population, 60 percent Chinese population were found in less than 20 percent total US population and 80 percent in 50 percent. By studying the Chinese population distribution and the reason behind it, we hope to find some interesting relationships among the characteristics of this distribution and the historical, cultural, social and economic factors influencing it.展开更多
In this article the supercritical bisexual Galton-Watson branching processes with the immigration of mating units is considered. A necessary condition for the almost sure convergence, and a sufficient condition for th...In this article the supercritical bisexual Galton-Watson branching processes with the immigration of mating units is considered. A necessary condition for the almost sure convergence, and a sufficient condition for the L^1 convergence are given for the process with the suitably normed condition.展开更多
The increasing amounts of artificial marine substrates, in many parts of the world have been proposed as a potential driver of Aurelia spp. blooms, on account of providing extra habitats for the settlement and the pro...The increasing amounts of artificial marine substrates, in many parts of the world have been proposed as a potential driver of Aurelia spp. blooms, on account of providing extra habitats for the settlement and the proliferation of the benthic stage(polyps). Previous experiments have mainly focused on the substrate choices of Aurelia spp. planulae. However, substrate preferences for the proliferation and immigration of polyps have not been reported. We monitored the propagation and immigration of Aurelia aurita(s. l.) polyps on two natural and nine artificial substrates at constant temperature(20±0.5°C) and salinity(30±0.5) in beakers and a glass aquarium in the laboratory, respectively. The results showed that, among artificial substrates, the highest number for polyp proliferation and immigration was found on nets, rigid polyvinyl chloride plates(RPVC), and wood. The lowest density of polyps was present on iron plates. Among natural substrates, the asexual reproduction rate of polyps on Patinopecten yessoensis(Jay, 1857) shells was significantly higher than Azumapecten farreri(Jones & Preston, 1904). On the account of the distinction in the roughness, chemical properties and biofilms of these material surfaces, bare artificial or natural substrates discriminatively affect the proliferation and the immigration of Aurelia spp. polyps at laboratory. These observations suggest that, even in the natural environment, different materials and texture may influence the composition and the abundance of the fouling communities and the assemblages of polyps and, indirectly, have effects on the amounts of released medusae.展开更多
Microbial immigrants arriving with influent wastewater may influence activated sludge(AS)ecosystems.However,the extent to which immigration impacts AS communities is still debated.To explore the intensity of immigrati...Microbial immigrants arriving with influent wastewater may influence activated sludge(AS)ecosystems.However,the extent to which immigration impacts AS communities is still debated.To explore the intensity of immigration impact,we used sequencing technology to track the raw wastewater and AS communities from a membrane bioreactor plant over a 12-month period.We first distinguished core populations from peripheral ones in both raw wastewater and AS based on their occurrence frequency and abundance.The results showed that core OTUs(≥80%occurrence frequency)made up a large fraction(>90%)of total sequences,while peripheral OTUs composed the majority of all detected OTUs but merely occupied a few sequences.A significant difference in core communities between the influent and AS was found,as well as between the compositions of core and peripheral populations.Additionally,the persistent functional bacteria of AS,although not numerically dominant,accounted for 96.24%of the total sequences related to nutrient turnover,suggesting the presence of a small number of longstanding and core functional bacteria in the AS ecosystem.Importantly,64%of the 5188 OTUs in AS,which accounted for 91.51%of the sequences,exhibited positive growth rates,which suggested that their apparent abundances were due to growth within the plant,not from immigration.Taken together,these results demonstrated that the impact of influent populations on core AS communities was limited.Overall,this work provides quantitative insights into the impact of immigration,which is expected to advance our understanding of the AS community assembly.展开更多
In order to find out the effect of human (sexual) behavior change and immigration in spreading the HIV/AIDS, a deterministic model of HIV/AIDS with infective immigration is formulated. First, basic properties of the m...In order to find out the effect of human (sexual) behavior change and immigration in spreading the HIV/AIDS, a deterministic model of HIV/AIDS with infective immigration is formulated. First, basic properties of the model, including non-negativity and boundedness of the solutions, existence of the endemic equilibrium and the basic reproduction number, R0 are analyzed. The geometrical approach is used to obtain the global asymptotic stability of endemic equilibrium. Then the basic model is extended to include several control efforts aimed at reducing infection and changing behavior. Pontryagin’s maximum principle is used to derive the optimality system and solve the system numerically. Our numerical findings are illustrated through simulations using MATLAB, which shows reliability of our model from the practical point of view.展开更多
This paper seeks to present how people＇s attitudes change according to the religion of immigrants and how this affects the immigrants＇ citizenship process in the USA. In general, immigration is a controversial issue...This paper seeks to present how people＇s attitudes change according to the religion of immigrants and how this affects the immigrants＇ citizenship process in the USA. In general, immigration is a controversial issue, for that reason people may conceal their real thoughts and have a tendency to give the socially accepted answers. For that reason, in this paper the list experiment method is used to get the real opinions of people. Results indicate that, people in fact conceal their real thoughts in response to direct survey questions. In addition, the results show that Americans are generally concerned about immigration. However, when it is compared to Muslim and Christian immigrants, people are more likely to support granting citizenship to a Christian immigrant compared to a Muslim immigrant. The other most important finding is that being against Muslim immigrants is considered more acceptable. In other words, people may feel pressure to say that they do not support Muslim immigration, for that reason when it is asked directly, some people （more than 10%） automatically say that they are against Muslim immigrants compared to the findings in the list experiment.展开更多
In a commercialized and fragment media market where crisis and humanitarian interventions are big news that sells, how do politicians and the public respond to them？ Bearing in mind that immigration is a phenomenon w...In a commercialized and fragment media market where crisis and humanitarian interventions are big news that sells, how do politicians and the public respond to them？ Bearing in mind that immigration is a phenomenon with a growing presence in society and increasingly politicized, this paper explores an important and persistent question regarding the role of news media in affecting policy decisions, particularly during times of crisis （Paletz, 1998）, transference of the issue and the media frames occurs. Having taken into account the agenda building paradigm and the concept of flame （Entman, 1993; Snow ＆ Benford, 1988）, the topic of immigration is analyzed in the Spanish main newspapers （El Pais ＆ El Mundo） and in the political interventions （Parliamentary Debates）. In order to implement this extraction and framing analysis, the associative method is adopted. The assaults of Ceuta and Melilla （2005） and the Canarias crisis （2006） are taken as the cases of study. The findings of this research highlight that moments of humanitarian crisis and key newsworthy events related to African immigrants increase the media＇s power to introduce the issue of immigration and to have influence on the frames used in the political and public agenda.展开更多
My principal objective in this paper is to examine what position liberal egalitarians should take regarding the issue of immigration. Given that liberal egalitarians grant central importance to individual autonomy and...My principal objective in this paper is to examine what position liberal egalitarians should take regarding the issue of immigration. Given that liberal egalitarians grant central importance to individual autonomy and the moral equality of all persons, their rejection of restrictive immigration policies appears to follow from these central normative commitments. Liberal egalitarians such as Joseph Carens and Phillip Cole have argued that those who are committed to individual autonomy and moral equality should advocate for an open borders position in immigration. I argue that it is a serious mistake for liberal egalitarians to advocate open national borders and that borders should instead be strategically regulated to reduce global economic inequalities through immigration policies systematically integrated into development programs for the poorest and most vulnerable countries. Open borders would create an open market for immigration slots to choice countries of destination, which out of practical necessity would have to delimit the number of new immigrants. It is well known in migration studies that those who are more educated, young, and have more resources are more likely to migrate than the very young, the elderly, the infirm, and the poorest individuals. Those left behind in developing countries suffer serious negative consequences from the emigration of the most highly educated, capable, and talented individuals in their society. I then argue that liberal egalitarians should grant particular moral consideration to the world＇s poorest and most vulnerable and that immigration policies strategically designed to prioritize their needs are actually more consistent with the dual commitments of individual autonomy and moral equality than an open borders position. I propose three principles of global justice that are consistent with liberal egalitarianism that should guide transnational moral obligations. I end the paper by arguing that two of these principles can be used to justify restricted immigration policies that would enable developed countries to partially discharge some of their moral obligations to developing countries while enhancing the autonomy of the world＇s most vulnerable people.展开更多
Laos was once unique in Southeast Asia for its remarkably small overseas Chinese communities. Most of them fled this country when the communist forces seized power in 1975. Since Laos opened its economy in 1986, the C...Laos was once unique in Southeast Asia for its remarkably small overseas Chinese communities. Most of them fled this country when the communist forces seized power in 1975. Since Laos opened its economy in 1986, the Chinese in Laos have been able to develop in many areas. Especially, the visit of Premier LI Peng to Vientiane in 1990 marked a turning point in China-Laos relations. Unlike Cambodia, the reawakening of a Chinese community in Laos did not come from the Huaqiao, this arose from a new cycle of immigrants, who started pouring into northern Laos in the late 1990s at an unprecedented scale. Compared with other Southeast Asian nations, the Chinese in Laos are less in number and weaker in economic power. In this study, we focus on （1） Analysis the ways of the new Chinese immigrants in Laos; （2） Assess the role of new Chinese immigrants in the process of China increasing their influence in Laos and how Laos response to this issue; and （3） The trend of new Chinese immigrants in Laos in the near future. Firstly, the rapid of Chinese investment to Laos in the last two decades is the most important factor driving the Chinese migrants into this country. The first new Chinese immigrants arrived in the mid-1990s as workers or technicians on road construction projects and as part of the industrial cooperation between Yunnan and the northern provinces of Laos. Since the 2000s, China has been pouring aid and investment into Laos. Chinese companies are involved in almost all areas of this country＇s economy, from hydropower to mining, agriculture, service, and hospitality. The increasing of Chinese exports, investment, aids and Chinese contracted project constructions in Laos led to mass Chinese immigrants going to Laos to work in all the economic sectors which the Chinese are involved in this country. Most of them chose to stay on and started their own businesses. Secondly, the wave of new Chinese immigrants in Laos helps Chinese government to relieve the pressure of solving jobs for their citizens. The semi-skilled and unskilled labor can go to Laos to work for the Chinese companies. Moreover, the outflow of petty traders has been prompted by the oversupply of certain goods in China as well as intense domestic competition. The investors also can find the better developing business opportunities. Although, the increasing of new Chinese immigrants make the local society change so much. Some Laotians feel cautious about the presence of so many Chinese people in Laos. Thirdly, with the increasing of Chinese＇s influence in Laos, especially in the economic, the position of the Chinese community in Laos will grow stronger in both quantity and economic and political status. Assessing the trend of increasing of new Chinese immigrations in Laos and the growth of the Chinese community are seen by the Laos government creating favorable conditions for China＇s investment, commercial activity, tourism activities, and cultural exchanges.展开更多
Since 1970s, illegal immigrants have become a hot topic in the US with the increase of number of illegal immigrants, Congress passed Immigration Reform and Control Act of 1986 （IRCA）. IRCA is the first legislation t...Since 1970s, illegal immigrants have become a hot topic in the US with the increase of number of illegal immigrants, Congress passed Immigration Reform and Control Act of 1986 （IRCA）. IRCA is the first legislation towards illegal immigration, which is very important in immigration history. Does this legislation work？ What＇s the role of Congress in controlling illegal immigration and what＇s the lesson from IRCA？ In a short term, IRCA worked. It deterred illegal immigrants and the number of illegal immigrants was on the decline, but in the long run, it failed. From the perspective of decision-making, the role of Congress was not powerful because of the influence of interest groups. Therefore, Congress should be more powerful in the future.展开更多
Immigration issue is one of the major problems in China today.The implementation of disasterinduced immigration policy is a significant contributor to effectively promote targeted measures of helping people in contigu...Immigration issue is one of the major problems in China today.The implementation of disasterinduced immigration policy is a significant contributor to effectively promote targeted measures of helping people in contiguous poor areas with particular difficulties to be out of poverty.Empirical investigation has been conducted to get a systematic grasp of the implementation deviation of massive disaster-induced immigration phenomenon in southern Shaanxi area.According to the survey,phenomenon of "immigrate the rich,while abandoning the poor,more houses with fewer immigrants,four moves and four drops,poor spot choosing and relaxed project management" demands improvement of execution ability.The implementation of such public policy has a large space to improve.Enough attention should be paid to the negative impact of such deviation,and only in this way can we live up to the desired objectives.展开更多
The new immigration policies introduced by Trump administration have saturated the world's screens,which have gained a mixed reception from the higher education circles amid considerable controversy,exacerbating t...The new immigration policies introduced by Trump administration have saturated the world's screens,which have gained a mixed reception from the higher education circles amid considerable controversy,exacerbating the plight of the brain drains,hurting the enthusiasm of those who have a strong desire to live in the USA,particularly the college leavers,and triggering a decline in the quality of education for foreign students,which could be a game-changer in the competition pattern of higher education and loom large.On this occasion,in matters of China,some more robust methodologies are to jump at the chance,attract qualified personnel and present some more aggressive human resources strategies.展开更多
文摘The importance of water to our lives cannot be overemphasized as it is the source of all living things. Water scarcity is a concern in many Middle Eastern nations due to war and politics. Many people lose their essence due to actions made by their rulers, such as the Marsh Arabs. Water and biodiversity should be considered, and governments should be held accountable for attaining a more balanced lifestyle and reducing immigrant levels. Many academics have also explored the hydro-immigration of marshland residents. They suffer more hazards due to a lack of money, poor education, and social instability than their colleagues who remain in their own country. Furthermore, they have insufficient health care and have difficulty integrating into the new community. This implies that not all nations that receive such migrants can implement programs to assist the immigrants. This research reveals how wars, hydro-politics, and immigration issues have drastically affected architecture and social structures in the Arab Marshes region, leading to ecological destruction, mass migrations, and cultural loss. Therefore, this work focuses on the need to critically investigate all factors covered within the context of this research.
文摘Organizations regardless of size can take advantage of the market dynamics brought about by globalization.Supply chain management is crucial for large organizations,especially with regard to the costs,complexity,and risks of its large,often global,supply chains.From technology to risk management,learning what it takes to navigate transportation and logistics business management in today’s volatile world is critical.Human migration has accelerated in light of globalization and rapid advances in transportation(particularly aviation)technology.This study investigated the connection between logistics and supply chain management in the age of globalization;reviewed the migration,settlement,and naturalization of Taiwan region of China immigrants along the West Coast of the United States;and theoretically analyzed the forces that have led to the construction of the Taiwan region of China immigrant community.Taiwan region of China immigrants and their settlement are affected by global forces,and factors such as their cross-cultural trade,the characteristics of diasporic communities,and their national identity can provide scholarly and pedagogical insights.
基金supported by Shaanxi Agricultural Collaborative Innovation and Promotion Alliance Foundation (Grant No. LM20150015)Shaanxi Key Theoretical & Realistic Projects of Social Science Research Foundation (Grant No. 2015Z023)
文摘Immigration relocation of the poor in rural areas is an effective targeted measure to help people out of poverty in the new normal. The structural constraints lie in the heavy pressure of land resources and environmental carrying capacity, high cost of immigration settlement and delayed counterpart funds, insufficient industrial support and difficulty in living-making. To realize the goal of targeted poverty alleviation, it demands determination and capability from the policy designer, as well the social basis. The effect imposed by the structural constraints to implementation of such policy should be paid adequate attention by public sectors. It is supposed to change the guiding direction of the policy timely and to relieve financial burden of immigration settlement and resource environmental bearing capacity through mechanism of joint efforts from internal and more external support.
基金supported by the National Natural Science Foundation for Young Scholars of China(No.51208414)the Education Department of Shaanxi Province Special Scientific Research(No.12JK0650)
文摘Two sequencing batch reactors（SBRs） were operated for 100 days under aerobic conditions,with one being fed with unsterilized municipal wastewater（USBR）, and the other fed with sterilized municipal wastewater（SSBR）. Respirometric assays and fluorescence in situ hybridization（FISH） results show that active nitrifiers were present in the unsterilized influent municipal wastewater. The maximum ammonia utilization rate（AUR） and nitrite utilization rate（NUR） of the unsterilized influent were 0.32 ± 0.12 mg NH4＋-N/（L·hr） and0.71 ± 0.18 mg NO2--N/（L·hr）. Based on the maximum utilization rates, the estimated seeding intensity for the ammonia oxidizing bacteria（AOB） and nitrite oxidizing bacteria（NOB） of the USBR was 0.08 g AOB/（g AOB·day） and 0.20 g NOB/（g NOB·day） respectively. The fraction of nitrifiers/total bacteria in the influent was 5.35% ± 2.1%, the dominant AOB was Nitrosomonas spp., Nitrosococcus mobilis hybridizated with Nsm156, and the dominant NOB was Nitrospira hybridizated with Ntspa662. The influent nitrifiers potentially seeded the activated sludge of the bioreactor and hence demonstrated a mitigation of the acclimatization times and instability during start-up and early operation. The AUR and NUR in the USBR was 15% and 13% higher than the SSBR respectively during the stable stage, FISH results showed that nitrifiers population especially the Nitrospira in the USBR was higher than that in the SSBR. These results indicate that the natural continuous immigration of nitrifiers from municipal influent streams may have some repercussions on the modeling and design of bioreactors.
基金partially supported by the National Nature Science Foundation of China(11601286,11501146)。
文摘Let(Z_(n))be a branching process with immigration in a random environmentξ,whereξis an independent and identically distributed sequence of random variables.We show asymptotic properties for all the moments of Z_(n) and describe the decay rates of the n-step transition probabilities.As applications,a large deviation principle for the sequence log Z_(n) is established,and related large deviations are also studied.
基金supported by the National Natural Science Foundation of China(11571052,11731012)the Hunan Provincial Natural Science Foundation of China(2018JJ2417)the Open Fund of Hunan Provincial Key Laboratory of Mathematical Modeling and Analysis in Engineering(2018MMAEZD02)。
文摘We are interested in the convergence rates of the submartingale Wn=Z_(n)/Π_(n)to its limit W,where(Π_(n))is the usually used norming sequence and(Z_(n))is a supercritical branching process with immigration(Y_(n))in a stationary and ergodic environmentξ.Under suitable conditions,we establish the following central limit theorems and results about the rates of convergence in probability or in law:(i)W-W_(n) with suitable normalization converges to the normal law N(0,1),and similar results also hold for W_(n+k)-W_(n) for each fixed k∈N^(*);(ii)for a branching process with immigration in a finite state random environment,if W_(1) has a finite exponential moment,then so does W,and the decay rate of P(|W-W_(n)|>ε)is supergeometric;(iii)there are normalizing constants an(ξ)(that we calculate explicitly)such that a_(n)(ξ)(W-W_(n))converges in law to a mixture of the Gaussian law.
基金supported by National Key Research and Development Project(2019YFA802703)National Natural Science Foundation of China Grants(331822033,31771623,32000568)+1 种基金Fundamental Research Funds for the Central Universities Grant(XDJK2020C041)Natural Science Foundation of Chongqing(CSTC2020JCYJMSXMX0104)。
文摘T cells play a critical role in immunity to protect against pathogens and malignant cells.T cell immunodeficiency is detrimental,especially when T cell perturbation occurs during severe infection,irradiation,chemotherapy,and age-related thymic atrophy.Therefore,strategies that enhance T cell reconstitution provide considerable benefit and warrant intensive investigation.Here,we report the construction of a T cell ablation model in Tg(coro1a:Den NTR)zebrafish via metronidazole administration.The nascent T cells are mainly derived from the hematopoietic cells migrated from the kidney,the functional homolog of bone marrow and the complete recovery time is 6.5 days post-treatment.The cxcr4b gene is upregulated in the responsive hematopoietic cells.Functional interference of CXCR4 via both genetic and chemical manipulations does not greatly affect T lymphopoiesis,but delays T cell regeneration by disrupting hematopoietic migration.In contrast,cxcr4b accelerates the replenishment of hematopoietic cells in the thymus.Consistently,Cxcl12b,a ligand of Cxcr4,is increased in the thymic epithelial cells of the injured animals.Decreased or increased expression of Cxcl12b results in compromised or accelerated T cell recovery,respectively,similar to those observed with Cxcr4b.Taken together,our study reveals a role of CXCR4-CXCL12 signaling in promoting T cell recovery and provides a promising target for the treatment of immunodeficiency due to T cell injury.
文摘In 1994, the total Chinese population in the United States were 2,017,799 which were 0.8 percent of the total US population. The Chinese population were highly concentrated by regions and among the total population. By states, 42 percent of total Chinese population were found in California, 17 percent in New York. More than 80 percent total Chinese population were concentrated in 9 states. By metropolitan areas, 14.73 percent of total Chinese population were found in Los Angeles and New York respectively. Compared with the total US population, 60 percent Chinese population were found in less than 20 percent total US population and 80 percent in 50 percent. By studying the Chinese population distribution and the reason behind it, we hope to find some interesting relationships among the characteristics of this distribution and the historical, cultural, social and economic factors influencing it.
文摘In this article the supercritical bisexual Galton-Watson branching processes with the immigration of mating units is considered. A necessary condition for the almost sure convergence, and a sufficient condition for the L^1 convergence are given for the process with the suitably normed condition.
基金Supported by the State Key Program of National Natural Science of China(No.41230963)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA11020305)+1 种基金the Shandong Joint Fund for Marine Ecology and Environmental Sciences(No.U1406403)the National Natural Science Foundation of China(No.41506144)
文摘The increasing amounts of artificial marine substrates, in many parts of the world have been proposed as a potential driver of Aurelia spp. blooms, on account of providing extra habitats for the settlement and the proliferation of the benthic stage(polyps). Previous experiments have mainly focused on the substrate choices of Aurelia spp. planulae. However, substrate preferences for the proliferation and immigration of polyps have not been reported. We monitored the propagation and immigration of Aurelia aurita(s. l.) polyps on two natural and nine artificial substrates at constant temperature(20±0.5°C) and salinity(30±0.5) in beakers and a glass aquarium in the laboratory, respectively. The results showed that, among artificial substrates, the highest number for polyp proliferation and immigration was found on nets, rigid polyvinyl chloride plates(RPVC), and wood. The lowest density of polyps was present on iron plates. Among natural substrates, the asexual reproduction rate of polyps on Patinopecten yessoensis(Jay, 1857) shells was significantly higher than Azumapecten farreri(Jones & Preston, 1904). On the account of the distinction in the roughness, chemical properties and biofilms of these material surfaces, bare artificial or natural substrates discriminatively affect the proliferation and the immigration of Aurelia spp. polyps at laboratory. These observations suggest that, even in the natural environment, different materials and texture may influence the composition and the abundance of the fouling communities and the assemblages of polyps and, indirectly, have effects on the amounts of released medusae.
基金supported by the National Natural Science Foundation of China(Nos.51622813,51608546,and 51478487)the Natural Science Foundation of Guangdong Province(No.2014A030306002)China Postdoctoral Science Foundation(No.2019M662839)。
文摘Microbial immigrants arriving with influent wastewater may influence activated sludge(AS)ecosystems.However,the extent to which immigration impacts AS communities is still debated.To explore the intensity of immigration impact,we used sequencing technology to track the raw wastewater and AS communities from a membrane bioreactor plant over a 12-month period.We first distinguished core populations from peripheral ones in both raw wastewater and AS based on their occurrence frequency and abundance.The results showed that core OTUs(≥80%occurrence frequency)made up a large fraction(>90%)of total sequences,while peripheral OTUs composed the majority of all detected OTUs but merely occupied a few sequences.A significant difference in core communities between the influent and AS was found,as well as between the compositions of core and peripheral populations.Additionally,the persistent functional bacteria of AS,although not numerically dominant,accounted for 96.24%of the total sequences related to nutrient turnover,suggesting the presence of a small number of longstanding and core functional bacteria in the AS ecosystem.Importantly,64%of the 5188 OTUs in AS,which accounted for 91.51%of the sequences,exhibited positive growth rates,which suggested that their apparent abundances were due to growth within the plant,not from immigration.Taken together,these results demonstrated that the impact of influent populations on core AS communities was limited.Overall,this work provides quantitative insights into the impact of immigration,which is expected to advance our understanding of the AS community assembly.
文摘In order to find out the effect of human (sexual) behavior change and immigration in spreading the HIV/AIDS, a deterministic model of HIV/AIDS with infective immigration is formulated. First, basic properties of the model, including non-negativity and boundedness of the solutions, existence of the endemic equilibrium and the basic reproduction number, R0 are analyzed. The geometrical approach is used to obtain the global asymptotic stability of endemic equilibrium. Then the basic model is extended to include several control efforts aimed at reducing infection and changing behavior. Pontryagin’s maximum principle is used to derive the optimality system and solve the system numerically. Our numerical findings are illustrated through simulations using MATLAB, which shows reliability of our model from the practical point of view.
文摘This paper seeks to present how people＇s attitudes change according to the religion of immigrants and how this affects the immigrants＇ citizenship process in the USA. In general, immigration is a controversial issue, for that reason people may conceal their real thoughts and have a tendency to give the socially accepted answers. For that reason, in this paper the list experiment method is used to get the real opinions of people. Results indicate that, people in fact conceal their real thoughts in response to direct survey questions. In addition, the results show that Americans are generally concerned about immigration. However, when it is compared to Muslim and Christian immigrants, people are more likely to support granting citizenship to a Christian immigrant compared to a Muslim immigrant. The other most important finding is that being against Muslim immigrants is considered more acceptable. In other words, people may feel pressure to say that they do not support Muslim immigration, for that reason when it is asked directly, some people （more than 10%） automatically say that they are against Muslim immigrants compared to the findings in the list experiment.
文摘In a commercialized and fragment media market where crisis and humanitarian interventions are big news that sells, how do politicians and the public respond to them？ Bearing in mind that immigration is a phenomenon with a growing presence in society and increasingly politicized, this paper explores an important and persistent question regarding the role of news media in affecting policy decisions, particularly during times of crisis （Paletz, 1998）, transference of the issue and the media frames occurs. Having taken into account the agenda building paradigm and the concept of flame （Entman, 1993; Snow ＆ Benford, 1988）, the topic of immigration is analyzed in the Spanish main newspapers （El Pais ＆ El Mundo） and in the political interventions （Parliamentary Debates）. In order to implement this extraction and framing analysis, the associative method is adopted. The assaults of Ceuta and Melilla （2005） and the Canarias crisis （2006） are taken as the cases of study. The findings of this research highlight that moments of humanitarian crisis and key newsworthy events related to African immigrants increase the media＇s power to introduce the issue of immigration and to have influence on the frames used in the political and public agenda.
文摘My principal objective in this paper is to examine what position liberal egalitarians should take regarding the issue of immigration. Given that liberal egalitarians grant central importance to individual autonomy and the moral equality of all persons, their rejection of restrictive immigration policies appears to follow from these central normative commitments. Liberal egalitarians such as Joseph Carens and Phillip Cole have argued that those who are committed to individual autonomy and moral equality should advocate for an open borders position in immigration. I argue that it is a serious mistake for liberal egalitarians to advocate open national borders and that borders should instead be strategically regulated to reduce global economic inequalities through immigration policies systematically integrated into development programs for the poorest and most vulnerable countries. Open borders would create an open market for immigration slots to choice countries of destination, which out of practical necessity would have to delimit the number of new immigrants. It is well known in migration studies that those who are more educated, young, and have more resources are more likely to migrate than the very young, the elderly, the infirm, and the poorest individuals. Those left behind in developing countries suffer serious negative consequences from the emigration of the most highly educated, capable, and talented individuals in their society. I then argue that liberal egalitarians should grant particular moral consideration to the world＇s poorest and most vulnerable and that immigration policies strategically designed to prioritize their needs are actually more consistent with the dual commitments of individual autonomy and moral equality than an open borders position. I propose three principles of global justice that are consistent with liberal egalitarianism that should guide transnational moral obligations. I end the paper by arguing that two of these principles can be used to justify restricted immigration policies that would enable developed countries to partially discharge some of their moral obligations to developing countries while enhancing the autonomy of the world＇s most vulnerable people.
文摘Laos was once unique in Southeast Asia for its remarkably small overseas Chinese communities. Most of them fled this country when the communist forces seized power in 1975. Since Laos opened its economy in 1986, the Chinese in Laos have been able to develop in many areas. Especially, the visit of Premier LI Peng to Vientiane in 1990 marked a turning point in China-Laos relations. Unlike Cambodia, the reawakening of a Chinese community in Laos did not come from the Huaqiao, this arose from a new cycle of immigrants, who started pouring into northern Laos in the late 1990s at an unprecedented scale. Compared with other Southeast Asian nations, the Chinese in Laos are less in number and weaker in economic power. In this study, we focus on （1） Analysis the ways of the new Chinese immigrants in Laos; （2） Assess the role of new Chinese immigrants in the process of China increasing their influence in Laos and how Laos response to this issue; and （3） The trend of new Chinese immigrants in Laos in the near future. Firstly, the rapid of Chinese investment to Laos in the last two decades is the most important factor driving the Chinese migrants into this country. The first new Chinese immigrants arrived in the mid-1990s as workers or technicians on road construction projects and as part of the industrial cooperation between Yunnan and the northern provinces of Laos. Since the 2000s, China has been pouring aid and investment into Laos. Chinese companies are involved in almost all areas of this country＇s economy, from hydropower to mining, agriculture, service, and hospitality. The increasing of Chinese exports, investment, aids and Chinese contracted project constructions in Laos led to mass Chinese immigrants going to Laos to work in all the economic sectors which the Chinese are involved in this country. Most of them chose to stay on and started their own businesses. Secondly, the wave of new Chinese immigrants in Laos helps Chinese government to relieve the pressure of solving jobs for their citizens. The semi-skilled and unskilled labor can go to Laos to work for the Chinese companies. Moreover, the outflow of petty traders has been prompted by the oversupply of certain goods in China as well as intense domestic competition. The investors also can find the better developing business opportunities. Although, the increasing of new Chinese immigrants make the local society change so much. Some Laotians feel cautious about the presence of so many Chinese people in Laos. Thirdly, with the increasing of Chinese＇s influence in Laos, especially in the economic, the position of the Chinese community in Laos will grow stronger in both quantity and economic and political status. Assessing the trend of increasing of new Chinese immigrations in Laos and the growth of the Chinese community are seen by the Laos government creating favorable conditions for China＇s investment, commercial activity, tourism activities, and cultural exchanges.
文摘Since 1970s, illegal immigrants have become a hot topic in the US with the increase of number of illegal immigrants, Congress passed Immigration Reform and Control Act of 1986 （IRCA）. IRCA is the first legislation towards illegal immigration, which is very important in immigration history. Does this legislation work？ What＇s the role of Congress in controlling illegal immigration and what＇s the lesson from IRCA？ In a short term, IRCA worked. It deterred illegal immigrants and the number of illegal immigrants was on the decline, but in the long run, it failed. From the perspective of decision-making, the role of Congress was not powerful because of the influence of interest groups. Therefore, Congress should be more powerful in the future.
基金supported by the National Social Science Fond of China(Grant No.13XSH031)Shaanxi Key Theoretical & Realistic Projects of Social Science Research Foundation(Grant No.2015Z023)+1 种基金Shaanxi Agricultural Collaborative Innovation and Promotion Alliance Foundation(Grant No.LM2015015)the Fundamental Research Funds for the Central Universities(Grant No.2013RWYB09)
文摘Immigration issue is one of the major problems in China today.The implementation of disasterinduced immigration policy is a significant contributor to effectively promote targeted measures of helping people in contiguous poor areas with particular difficulties to be out of poverty.Empirical investigation has been conducted to get a systematic grasp of the implementation deviation of massive disaster-induced immigration phenomenon in southern Shaanxi area.According to the survey,phenomenon of "immigrate the rich,while abandoning the poor,more houses with fewer immigrants,four moves and four drops,poor spot choosing and relaxed project management" demands improvement of execution ability.The implementation of such public policy has a large space to improve.Enough attention should be paid to the negative impact of such deviation,and only in this way can we live up to the desired objectives.
文摘The new immigration policies introduced by Trump administration have saturated the world's screens,which have gained a mixed reception from the higher education circles amid considerable controversy,exacerbating the plight of the brain drains,hurting the enthusiasm of those who have a strong desire to live in the USA,particularly the college leavers,and triggering a decline in the quality of education for foreign students,which could be a game-changer in the competition pattern of higher education and loom large.On this occasion,in matters of China,some more robust methodologies are to jump at the chance,attract qualified personnel and present some more aggressive human resources strategies.
