CHRISTMAS TREE CONSUMPTION BEHAVIOR: NATURAL VS. ARTIFICIAL

Artificial Christmas trees have gained an increasing market share, causing concern to natural Christmas tree producers. Primary data was used to test a hypothesized sequential probit model of buyer characteristics. The model predicted the probability of using or displaying a Christmas tree, then if a use decision was made, the probability of displaying a natural tree. The people who are likely to display trees are Christian, practice other secular Christmas rituals, have children, and spend Christmas at home. Those who use natural trees are younger, white, have a higher income, and live in a single-family dwelling.Demand and Price Analysis,

Impact and implications of price policy and land degradation on agricultural growth in developing countries

In many developing countries, a high proportion of the population resides and works in rural areas. Agriculture is the dominant sector in rural areas and has the greatest concentration of poverty: landless workers, small tenant farmers, and small farm owners. Thus, any development strategy that is directed towards increasing employment and alleviating a country's hunger must concentrate on sustainable agricultural growth. Historically, economic development in most countries has been based on exploitation of natural resources, particularly land resources. Soil erosion and land degradation have been serious worldwide. Due to reasons such as high population pressure on land and limited fossil energy supplies, land degradation is generally more serious in the developing world. Empirical studies show that soil erosion and degradation of agricultural land not only decrease the land productivity but they can also result in major downstream or off-site damage which may be several times that of on-site damage. In promoting industrialization, governments of many developing countries adopt a package of price and other policies that reduce agricultural production incentives and encourage a flow of resources out of agriculture. Increasing evidence shows that these policies cause a substantial efficiency or social welfare loss, and a great loss in foreign exchange earnings. In addition, a World Bank study on the effect of price distortions on economic growth rates concluded that neither rich resource endowments, nor a high stage of economic development, nor privatization are able to make up the adverse effects caused by high price distortions. This analysis is primarily concerned with identifying the factors that determine the agricultural production growth rate and in testing the effects these factors have on agricultural growth in developing countries. Specifically, this study involves statistical estimation of an aggregate agricultural growth function based on cross-country data for 28 developingcountries. Special attention is devoted to land degradation and agricultural pricing policy, and to the policy implications resulting from the effects these variables have on agricultural and food production growth. The overall results of this study show that price distortions in the economy and land degradation had statistically significant negative impacts while the change in arable and permanent land was positively related to the growth of agricultural production and food production in 28 developing countries from 1971 to 1980. These results emphasize the importance of 'getting prices right' and implementation of sustainable land and water management practices if future growth in food and agricultural output is to be realized and sustained in developing countries

Establishment and application of a remote automatic control platform for CBM production

Remote data monitoring has been applied in the production of CBM wells. It is necessary to realize remote regulating and automatic control on production systems of CBM wells as soon as possible, so that production cost can be reduced effectively and fine production of CBM wells can be improved. In this paper, remote production control technologies were designed based on production behaviors of CBM wells. And then, in light of the features of automatic monitoring instruments, automatic production of CBM wells was divided into four stages (i.e. before casing pressure occurring, casing pressure building, initial gas production and gas production). Finally, an automatic control program was developed and embedded into on-site control terminals after study was carried out on automatic control logics and methods of each production stage of CBM wells. It is for the first time that gas and water production of CBM wells are automatically regulated precisely and automatic CBM production modes are adopted with the linkage control of gas and water production. Based on this production network and remote control platform system, terminal operation is controlled and feedback according to the production orders which are set and delivered remotely. In this way, CBM well production is automatically controlled over long distance. Practical operation results in the Hancheng area, Shaanxi, shows that establishment and application of this automatic control platform contribute to the improvement of fine production of CBM wells and their continuous and stable production

CHRISTMAS TREE CONSUMPTION BEHAVIOR: NATURAL VS. ARTIFICIAL

Artificial Christmas trees have gained an increasing market share, causing concern to natural Christmas tree producers. Primary data was used to test a hypothesized sequential probit model of buyer characteristics. The model predicted the probability of using or displaying a Christmas tree, then if a use decision was made, the probability of displaying a natural tree. The people who are likely to display trees are Christian, practice other secular Christmas rituals, have children, and spend Christmas at home. Those who use natural trees are younger, white, have a higher income, and live in a single-family dwelling

MLST subtypes and population genetic structure of Cryptosporidium andersoni from dairy cattle and beef cattle in northeastern China's Heilongjiang Province.

Cattle are the main reservoir host of C. andersoni, which shows a predominance in yearlings and adults of cattle. To understand the subtypes of C. andersoni and the population genetic structure in Heilongjiang Province, fecal specimens were collected from 420 dairy cattle and 405 beef cattle at the age of 12-14 months in eight cattle farms in five areas within this province and were screened for the presence of Cryptosporidium oocysts by microscopy after Sheather's sugar flotation technique. The average prevalence of Cryptosporidium spp. was 19.15% (158/825) and all the Cryptosporidium isolates were identified as C. andersoni by the SSU rRNA gene nested PCR-RFLP using SspI, VspI and MboII restriction enzymes. A total of 50 C. andersoni isolates were randomly selected and sequenced to confirm the RFLP results before they were subtyped by multilocus sequence typing (MLST) at the four microsatellite/minisatellite loci (MS1, MS2, MS3 and MS16). Four, one, two and one haplotypes were obtained at the four loci, respectively. The MLST subtype A4,A4,A4,A1 showed an absolute predominance and a wide distribution among the six MLST subtypes obtained in the investigated areas. Linkage disequilibrium analysis showed the presence of a clonal population genetic structure of C. andersoni in cattle, suggesting the absence of recombination among lineages. The finding of a clonal population genetic structure indicated that the prevalence of C. andersoni in cattle in Heilongjiang Province is not attributed to the introduction of cattle. Thus, prevention and control strategies should be focused on making stricter measures to avoid the occurrence of cross-transmission and re-infection between cattle individuals. These molecular data will also be helpful to explore the source attribution of infection/contamination of C. andersoni and to elucidate its transmission dynamics in Heilongjiang Province, even in China

Molecular characterization and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis in humans and domestic animals in Heilongjiang Province, China

Abstract Background Cryptosporidiosis and giardiasis are significant parasitic diseases shared between humans and domestic animals. Due to the close contact between humans and domestic animals in rural areas, it is important to consider the potential transmission of zoonotic parasites from infected domestic animals to humans. This investigation aimed to determine the prevalence and molecular characteristics of Cryptosporidium spp. and Giardia duodenalis in domestic animals and villagers. Methods A total of 116 fecal samples from villagers and 686 fecal samples from domestic animals in Heilongjiang Province, China, were analyzed for two parasites using nested polymerase chain reaction (PCR) targeting various genetic loci and DNA sequence analysis of the PCR products. Results By sequence analysis of the SSU rRNA gene, the prevalence of Cryptosporidium in humans was 0.9% (1/116), with one species of C. parvum (n = 1) detected; among domestic animals, the prevalence was 2.6% (18/686), with five species identified: C. suis (n = 7) and C. scrofarum (n = 7) in pigs, C. meleagridis (n = 1) in chickens, C. andersoni (n = 1) in cattle, and C. canis (n = 2) in foxes. C. parvum and C. canis were further subtyped as IIdA19G1 and XXa4 on the basis of gp60 gene. Regarding G. duodenalis, based on the SSU rRNA, bg, gdh, and tpi genes, the prevalence in domestic animals was 5.1% (31/608), with three assemblages identified: A (n = 1) in pigs, D (n = 1) in foxes, and E (n = 27) in geese, cattle, pigs, ducks, and sheep, along with mixed infection of A + E (n = 1) in one pig and B + E (n = 1) in one sheep. No G. duodenalis was detected in humans (0/116). Conclusions The present results show that no overlap of subtypes between animals and villagers was found in Cryptosporidium spp. and G. duodenalis, indicating a minor role of domestic animals in infecting humans in this population. However, the presence of zoonotic protozoa in domestic animals highlights the need for special attention to high-risk individuals during close contact with domestic animals. Graphical Abstrac

Distribution and genetic diversity of Blastocystis subtypes in various mammal and bird species in northeastern China

Abstract Background Blastocystis is one of the most common intestinal parasites in humans and animals worldwide. At least 17 subtypes have been identified in mammals and birds. In China, although some studies have reported the occurrence of Blastocystis in humans and animals, our understanding of the role of animals in the transmission of human blastocystosis is only superficial due to a paucity of available molecular data. The aim of the present study was to understand infection rates of Blastocystis and the distribution and genetic diversity of subtypes in various mammal and bird species in northeastern China, as well as to assess the zoonotic potential of Blastocystis isolates. Methods A total of 1265 fresh fecal specimens (1080 from ten mammal species and 185 from eight bird species) were collected in Heilongjiang, Liaoning and Jilin provinces of China. Each specimen was examined for the presence of Blastocystis by PCR amplification and sequence analysis of the partial SSU rRNA gene. Results Fifty-four specimens (4.3%) were positive for Blastocystis. Birds (7.0%) had a higher infection rate of Blastocystis than mammals (3.8%). Blastocystis was found in seven mammal species, reindeer (6.7%), sika deer (14.6%), racoon dogs (7.5%), Arctic foxes (1.9%), dogs (2.9%), rats (3.7%) and rabbits (3.3%), as well as three bird species, pigeons (2.1%), chickens (13.0%) and red crowned cranes (14.0%). Eight subtypes were identified including ST1 (n = 5), ST3 (n = 3), ST4 (n = 13), ST6 (n = 8), ST7 (n = 6), ST10 (n = 13), ST13 (n = 4) and ST14 (n = 2). 64.8% (35/54) of Blastocystis isolates belonged to potentially zoonotic subtypes. Conclusions To our knowledge, this is the first report of Blastocystis in reindeer (ST10 and ST13), rabbits (ST4), racoon dogs (ST3) and Arctic foxes (ST1, ST4 and ST7). The findings of potentially zoonotic subtypes suggest that the animals infected with Blastocystis might pose a threat to human health. These data will improve our understanding of the host range and genetic diversity of Blastocystis, and also help develop efficient control strategies to intervene with and prevent the occurrence of human blastocystosis in the investigated areas

Molecular characterizations of Cryptosporidium spp. and Enterocytozoon bieneusi in brown rats (Rattus norvegicus) from Heilongjiang Province, China

Abstract Background Cryptosporidium spp. and Enterocytozoon bieneusi are prevalent zoonotic pathogens responsible for the high burden of diarrheal diseases worldwide. Rodents are globally overpopulated and are known as reservoirs or carriers of a variety of zoonotic pathogens including Cryptosporidium spp. and E. bieneusi. However, few data are available on genetic characterizations of both pathogens in rodents in China. The aim of the present work was to determine the prevalence and genetic characterizations of Cryptosporidium spp. and E. bieneusi in brown rats (Rattus norvegicus) from Heilongjiang, China. Methods A total of 242 wild brown rats were captured in Heilongjiang Province of China. A fresh fecal specimen was collected directly from the intestinal and rectal content of each brown rat. All the fecal specimens were examined for the presence of Cryptosporidium spp. and E. bieneusi by PCR and sequencing of the partial small subunit (SSU) rRNA gene and the internal transcribed spacer (ITS) region of the rRNA gene of the two pathogens, respectively. Results The infection rate was 9.1% (22/242) for Cryptosporidium spp. and 7.9% (19/242) for E. bieneusi. Sequence analysis confirmed the presence of C. ubiquitum (1/22, 4.5%) and three genotypes of Cryptosporidium, including Cryptosporidium rat genotype I (14/22, 63.6%), Cryptosporidium rat genotype IV (6/22, 27.3%) and Cryptosporidium suis-like genotype (1/22, 4.5%). Meanwhile, two E. bieneusi genotypes were identified, including D (17/19, 89.5%) and Peru6 (2/19, 10.5%). Conclusions To the best of our knowledge, Enterocytozoon bieneusi genotype Peru6 was identified in rodents for the first time globally and Cryptosporidium rat genotype I and Cryptosporidium rat genotype IV were found in rats in China for the first time. The finding of zoonotic C. ubiquitum and C. suis-like genotype, as well as E. bieneusi genotypes, suggests that brown rats pose a threat to human health. It is necessary to control brown rat population in the investigated areas and improve local people’s awareness of the transmission risk of the two pathogens from brown rats to humans

Genetic analysis of the Gdh and Bg genes of animal-derived Giardia duodenalis isolates in Northeastern China and evaluation of zoonotic transmission potential.

BACKGROUND: Giardia duodenalis is a common intestinal parasite that infects humans and many other mammals, mainly distributing in some areas with poor sanitation. The proportion of the human giardiasis burden attributable to G. duodenalis of animal origin differs in different geographical areas. In Mainland China, genetic data of the gdh and bg genes of G. duodenalis from animals are only limited in dogs and cats. The aim of the study was to provide information on the genetic characterizations of animal-derived G. duodenalis isolates (from rabbits, sheep and cattle) at both loci in Heilongjiang Province, Northeastern China, and to assess the potential for zoonotic transmission. METHODOLOGY/PRINCIPAL FINDINGS: 61 G. duodenalis isolates from animal feces (dairy and beef cattle, sheep and rabbits) in Heilongjiang Province were characterized at the gdh and bg loci in the present study. The gdh and bg gene sequences of sheep-derived G. duodenalis assemblage AI, and the gdh sequences of rabbit-derived G. duodenalis assemblage B had 100% similarity with those from humans, respectively. Novel subtypes of G. duodenalis were identified, with one and seven subtypes for assemblages A and E at the gdh locus, and two and three subtypes for assemblages B and E at the bg locus, respectively. Three pairs of the same bg sequences of assemblage E were observed in sheep and cattle. CONCLUSIONS/SIGNIFICANCE: This is the first description of genetic characterizations of the gdh and bg genes of G. duodenalis from rabbits, sheep and cattle in Mainland China. Homology analysis of assemblages AI and B implied the possibility of zoonotic transmission. The novel subtypes of assemblages of G. duodenalis may represent the endemic genetic characteristics of G. duodenalis in Heilongjiang Province, China