bluuebunny/crossref_metadata_2025_split huggingface dataset:
Longevity and Genetic Improvement Issues in Replacing Dairy Cows
Authors: Bauer Leonard , Mumey Glen , Lohr Wayne 
Published: November 2008

The objective of this research is to identify optimal economic replacement strategies for dairy cows within the framework of genetic improvement and to compare these strategies with those followed by Alberta dairy farmers. Production records from four commercial dairy herds are used to model the optimum replacement policy within a wealth‐maximizing objective, allowing comparison of predicted results with observed practice in the industry. Unplanned replacement, due to biologial failure of cows, is included in the model as a finite Markov process. The economically optimal replacement time is found to occur at the end of the sixth lactation, with only minor penalties for suboptimality. Planned replacement after the sixth lactation requires culling approximately one quarter of the herd annually, and results in an average herd age of 5.77 years. Since the band of economically reasonable replacement policies extends from the third to the tenth lactation, the average herd age ranges from 4.48 years and 7.02 years. The observed average age of Alberta milking herds of 4. 78 years lies in the lower part of this predicted range. While one can conclude that the model leads to an optimum that is consistent with the observed behavior of Alberta dairy farmers, one must temper this conclusion with the caution that additional research, especially regarding the technical lactation curve, is indicatedL'objet de la présente recherche était de dégager des stratégies de remplacement economiquement opti‐males pour les vaches laitières, compte tenu des exigences de l'amelioration génétique, et de comparer ces stratégies avec celles qu'utilisent les producteurs laitiers de I 'Alberta. On a utilisé les relevés de production de quatre exploitations laitières commercials pour modéliser les stratégies de remplacement optimales dans un objectif de maximisation des revenus. Le modèle permet également de comparer les résultats prédits avec ceux observés sur le terrain. Les remplacements non prévus, à cause de défauts biologiques des vaches, étaient inclus dans le modèle comme processus de Markov fini. L'époque de remplacement économiquement optimale s'est révélée être le fin de la sixième lactation, avec seulement de légères pertes de rentabilité pour les situations suboptimales. Le remplacement planifié après la sixième lactation exigeait la mise à la réforme d'environ un quart du troupeau chaque année et donnait pour le troupeau un age moyen de 5,77 ans. Comme l'écart des possibilités de remplacement économiquement plausibles va de la troisième à la dixieme lactation, l'âge moyen des troupeaux se situe entre 4,48 et 7,02 ans. L'âge moyen réel des troupeaux laitiers de l'Alberta (4,78 ans) se situe dans le bas de eel écart de prédiction. Tout en reconnaissant que le modèle conduit à un optimum cohérent avec le comportentent réel des producteurs laitiers de l'Alberta, il reste qu'on a besoin de plus de recherche dans ce domaine, en particulier en ce qui concerne la courbe de lactation technique
A Maximum Likelihood Cointegration Analysis of Canadian Lumber Exports
Authors: Sarker Rakhal 
Published: November 2008

Johansen 's cointegration analysis is used to investigate causal relationships between Canadian lumber exports, U.S. lumber price, U.S. housing starts and the Canada‐U.S. exchange rate. The results suggest that there is only one stable equilibrium relationship among these variables in the long run. Forecast error variance decomposition and impulse responses from a vector error‐correction model are used to examine the short‐run dynamic relationships among the variables. The results suggest significant dynamic relationship among the variables. The results also indicate that the pass‐through of exchange rate is incomplete in the long run and that the effects of exchange rate on lumber exports vary between the short run and long runL'analyse de cointégration de Johansen est utilisée pour examiner les rapports de cause à effet entre les exportations de bois d'oeuvre canadien, le prix du bois d'oeuvre aux Etats‐Unis, les mises en chantier de constructions à usage d'habitation el le taux de change Canada‐Etats‐ Unis. Les résultats semblent montrer qu'il n 'v a à long terme qu'un seul rapport d'équilibre stable entre ces variables. On recourt à la decomposition de la variance de l'erreur de prédiction et aux réponses sur impulsion déhvées à partir d'un modèle de correction d'erreur vectorielpour examiner les rapports dynamiques à court terme entre les variables. Les résultats laissent apparaître un rapport dynamique significatif entre les variables. Ils montrent aussi que la transmission des effets du taux de change canado‐américain est incomplète à long terme et que les effets de cette variable sur les exportations canadiennes de bois d'oeuvre ne sont pas les mêmes à court qu'à long terme
Relative Technical Efficiency: Data Envelopment Analysis and Quebec's Dairy Farms
Authors: Cloutier L. Martin , Rowley Robin 
Published: November 2008

Data envelopment analysis (DEA) is used to explore the distribution of productive efficiency across some Quebec dairy farms in 1988 and 1989. Sensitivity checks are made with respect to sample size and herd size. Overall, efficiency scores from the DEA approach are reasonably informative, but some troublesome issues need to be resolvedL'analyse par enveloppement des données (AED) est utilisée afin d'explorer la distribution de l'effica‐cité relative à travers un échantillon de fermes laitières du Québec en 1988 et 1989. Les résultats sont comparés par rapport à la grandeur de l'échantillon et à la grosseur des troupeaux. Globalement. les résultats de l'AED sont interessants et informatifs, mais ils révélent quelques problèmes qui devront être étudiéis de plus près
Price Behavior of Canadian Farmland
Authors: Veeman M. M. , Dong X. Y. , Veeman T. S. 
Published: November 2008

A simple dynamic model is used to explain farmland price behavior in Canada and to explore the possible impact on land values of the elimination of direct government payments to agriculture. Based on the classic income capitalization approach, farmland prices are explained in terms of expected farmland earnings, incorporating a distributed lag structure on earnings. The model is applied to annual data from 1961 to 1987 for Canada, Ontario and each of the three prairie provinces; it performs well in explaining land price behavior over this period and in predicting price behavior to 1990. The model is then used to simulate the impact on farmland prices of a once‐and‐for‐all removal of net subsidies paid directly to farmers, all other things being equal. The results indicate a short‐run reduction of 5% in Canadian land values and a long‐run fall of 19%. However, the reaction varies by region, being about 12.2% in the long run in Ontario and 29.9% in Saskatchewan. Evidently, direct government payments to agriculture have had an appreciable impact in maintaining Canadian farmland values.Un modèle dynamique simple est utilisé pour expliquer le comportement des prix des terres agricoles au Canada ainsi que pour examiner les incidences éventuelles que pourrait avoir sur les prix l'élimination des aides directes de l'Etat à l'agriculture. A partir d'une démarche de capitalisation des revenus, les prix des terres agricoles sont expliqués en termes de gains escomptés, les gains étant incorporés dans une structure à retard échelonné. Le modéle est appliqué aux données annuelles recueillies de 1961 à 1987 pour l'ensemble du Canada, ainsi que pour l'Ontario et pour les trois provinces des Prairies. Le modèle a permis d'expliquer assez bien le comportement des prix des terres agricoles en fonction du temps et de prédire leur évolution jusqu'en 1990. Le modèle a ensuite été utilisé pour simuler les incidences que pourrait avoir sur les prix un retrait radical des aides directes de l'Etat, toutes choses étant égales d'ailleurs. Les résultats font voir dans la période courte une réduction de 5% et à long terme une baisse de 19% des prix des terres. Toutefois, la tendance varie d'une région à l'autre, passant de 12,2% environ en Ontario à 29,9% pour la Saskatchewan. Tout indique done que les aides directes de l'Etat à l'agriculture ont été un élément important dans le maintien des valeurs des terres agricoles au Canada
Back to Market: Polish Family Farming in the 1990s
Authors: Kowalski Zbigniew 
Published: November 2008

The economic reform in Poland has changed dramatically both the income and social position of farmers. The competitive structure of the farming sector versus the monopolized‐monopsonized economy, liberal agricultural import, and virtual lack o financial assistance from the state are the main features of the new situation. Specipc for the market reorientation of Polish agriculture has been the dramatic pace of the change. The paper highlights the background of the market reform in Polish agriculture, discusses accessible strategies and formulates some expectations for the future.La réforme économique en Pologne a modifié radicalement, à la fois, le revenu et la position sociale des agriculteurs. Le passage d'une économie de monopole‐monopsone à une structure concurrentielle du secteur agricole, la libération des importations agricoles et l'absence virtuelle de route aide jinancière de l'État sont les traits principaux de la nouvelle situation. Ce qui est particulier à la réorientation du marché agricole en Pologne c'est le rythme effréné auquel les transformations se sont produites. L'auteur examine les stratégies accessibles et formule quelques attentes pour l'avenir.
Treatment of hepatitis C virus with peg‐interferon and ribavirin combination therapy significantly affects lipid metabolism
Authors: Tada Shinichiro , Saito Hidetsugu , Ebinuma Hirotoshi , Ojiro Keisuke , Yamagishi Yoshiyuki , Kumagai Naoki , Inagaki Yasutaka , Masuda Tetsuya , Nishida Jiro , Takahashi Masahiko , Nagata Hiroshi , Hibi Toshifumi 
Published: November 2008

Aim:  We investigated lipid metabolism in patients with chronic hepatitis C virus (HCV), serotype 1, undergoing combination therapy with PEG‐IFN α‐2b (PEG‐IFN) and ribavirin (RBV).Methods:  A total of 185 patients with chronic HCV (HCV serotype 1; HCV RNA levels ≥ 100 KIU/mL) who received a combination of PEG‐IFN and RBV were enrolled.Results:  Sustained virological response (SVR) was obtained in 82 cases (44.3%). The median age, red blood cell and platelet counts differed significantly between the SVR and non‐SVR groups before treatment. However there was no significant difference between total cholesterol (TC), LDL‐cholesterol (LDL‐C) and triglyceride (TG) levels before treatment. TC and LDL‐C levels decreased during the treatment in both groups. In the SVR group, TC and LDL‐C levels increased quickly after the end of the treatment and were higher than those before treatment. On the other hand, TC and LDL‐C levels returned to pretreatment levels in the non‐SVR group and were significantly lower than in the SVR group. TG levels were elevated in both groups after the beginning of treatment. After the end of treatment, this elevation persisted in the SVR group, while TG levels returned to pre‐treatment levels in the non‐SVR group. There was a significant difference in TG levels at 24 weeks after the end of the treatment between the 2 groups. In the non‐SVR group some patients achieved normalization of ALT (alanine aminotransferase) but persistence of normal ALT levels did not contribute to the increase of TC and TG.Conclusion:  TC, LDL‐C and TG levels increase only in patients with HCV, serotype 1, undergoing combination therapy when a SVR is achieved.
Combination therapy of radiofrequency ablation and transarterial chemoembolization in recurrent hepatocellular carcinoma after hepatectomy compared with single treatment
Authors: Yang Wei , Chen Min Hua , Wang Mao Qiang , Cui Ming , Gao Wen , Wu Wei , Wu Jin Yu , Dai Ying , Yan Kun 
Published: November 2008

Aim:  To assess the efficacy and safety of radiofrequency ablation (RFA) combined with transarterial chemoembolization (TACE) in recurrent hepatocellular carcinoma (HCC) after hepatectomy and to compare its outcome with a single modality.Method:  We retrospectively studied 103 patients with recurrent HCCs after hepatectomy who were excluded from repeat hepatectomy. Of them, 81 patients were male and 22 were female (mean age 55.8 ± 10.7 years; range, 30–80 years). According to treatment modality, these patients were divided into three groups: RFA was used as the sole first‐line anticancer treatment in 37 patients (RFA group); TACE was used as the sole first‐line anticancer treatment in 35 patients (TACE group). RFA followed by TACE was performed in 31 patients (combination group). There was no significant difference in clinical material between the three groups. Indices including treatment success rate, intrahepatic recurrence rate and survival were obtained for analysis and comparison.Results:  The treatment success rate of the combination group was significantly higher than that of the TACE group (93.5 vs. 68.6%, P = 0.011). The intrahepatic recurrence rate of the combination group was significantly lower than that of the TACE group (20.7 vs 57.1%, P = 0.002) and the RFA group (20.7 vs 43.2%, P = 0.036). The overall 1‐, 3‐ and 5‐year survival rates were 73.9, 51.1 and 28.0% respectively in the RFA group; 65.8, 38.9 and 19.5% respectively in the TACE group; and 88.5, 64.6 and 44.3% respectively in the combination group. There was a significant difference in survival between the combination group and the TACE group (P = 0.028).Conclusion:  RFA combined with TACE was more effective in treating recurrent HCC after hepatectomy compared to single RFA or TACE treatment. This combination therapy can thus be a valuable choice of treatment for recurrent HCC.
Microsatellite instability in hepatocellular carcinoma in non‐cirrhotic liver in patients older than 60 years
Authors: Togni Roberto , Bagla Nipin , Muiesan Paolo , Miquel Rosa , O'Grady John , Heaton Nigel , Knisely Alex S , Portmann Bernard , Quaglia Alberto 
Published: November 2008

Aim:  Hepatocellular carcinoma (HCC) in otherwise normal liver is rare, its pathogenesis remains obscure and the literature on the subject is scarce. We investigated microsatellite instability (MSI) in eight elderly patients (median age 70.7, range 63–76 years) without a clinical history of liver disease and who underwent liver resection for HCC in otherwise normal background liver between 2001 and 2005 at King's College Hospital, London.Methods:  Immunohistochemistry for mutL homolog 1 (MLH1), mutS homolog 2 (MSH2), mutS homolog 6 (MSH6) and post‐meiotic segregation increased 2 (PMS2) was carried out on formalin‐fixed and paraffin‐embedded sections of tumor and background liver. MSI analysis was performed using a panel of monomorphic microsatellites markers: BAT‐25, BAT‐26, NR21, NR24 and NR27 and pentaplex PCR.Results:  All HCC were solitary large tumors. Two also had satellite nodules. The background liver was usually unremarkable. There was nuclear expression of MLH1, MSH2, MSH6 and PMS2 in all tumors excluding a DNA mismatch repair defect. The same pattern of staining was noted in the hepatocytes of the background liver of all cases. No differences between microsatellite lengths in the background liver and in the tumor, as assessed in PCR products, were found for any of the five microsatellite markers in any patients. These findings provided no evidence for MSI.Conclusion:  Our study showed that MSI is not implicated in the pathogenesis of a subset of HCC affecting elderly patients without chronic liver disease. Further studies are needed to clarify the pathogenesis of HCC in this particular setting.
Impact of determination of hepatitis B virus subgenotype and pre‐core/core‐promoter mutation for the prediction of acute exacerbation of asymptomatic carriers
Authors: Ikegami Tadashi , Matsuki Yasuhiko , Tanaka Yasuhito , Mizokami Masashi , Honda Akira , Hirayama Takeshi , Saito Yoshifumi , Matsuzaki Yasushi 
Published: November 2008

Aim:  A large cohort study in Japan revealed that the specific viral profile may influence the fulminant outcome in acute hepatitis B virus (HBV) infections, while the genetic influence on outcome has not been clarified in patients with acute exacerbation of chronic liver disease caused by HBV. We experienced a case of fatal liver failure that developed as the result of chronic HBV infection. To determine possible genetic factor involving acute exacerbation, genetic analysis of serum from the patient and his siblings was performed.Methods:  HBV subgenotype as well as pre‐core/core‐promoter mutations of samples mentioned above were determined.Results:  Patient had HBV‐Bj with pre‐core (1896/1899) and core‐promoter (1762/1764) mutations, the genomic profile frequently seen in fulminant hepatitis caused by acute HBV infection.Conclusion:  This result suggests that determination of the HBV subgenotype and pre‐core/core promoter mutations could provide a rationale for development of a treatment strategy in asymptomatic HBV carriers.
Influence of Common and Specific HLA-DRB1/DQB1 Haplotypes on Genetic Susceptibilities of Three Distinct Arab Populations to Type 1 Diabetes
Authors: Stayoussef Mouna , Benmansour Jihen , Al-Jenaidi Fayza A. , Nemr Rita , Ali Muhallab E. , Mahjoub Touhami , Almawi Wassim Y. 
Published: November 2008

ABSTRACT

The contribution of HLA DRB-DQB to type 1 diabetes (T1D) in Bahrainis, Lebanese, and Tunisians was investigated.
DRB1*030101-DQB1*0201
was a locus that conferred susceptibility in three populations, while
DRB1*040101-DQB1*0302
was a locus that conferred susceptibility only in Tunisians and Bahrainis. The
DRB1*100101-DQB1*050101
(Bahrainis) and
DRB1*150101-DQB1*060101
(Lebanese) loci were largely protective. The contribution of HLA to T1D must be evaluated with regard to ethnic background.
Pediatric Antibody Response to Community-Acquired
Staphylococcus aureus
Infection Is Directed to Panton-Valentine Leukocidin
Authors: Brown Eric L. , Bowden M. Gabriela , Bryson Rebecca S. , Hulten Kristina G. , Bordt Andrea S. , Forbes Andrea , Kaplan Sheldon L. 
Published: November 2008

ABSTRACT

We examined the antibody responses of pediatric patients infected with community-associated
Staphylococcus aureus
isolates. The data show that patients infected with Panton-Valentine leukocidin (PVL)-positive strains developed a dominant immunoglobulin G anti-PVL antibody response that correlates with markers of inflammation.
Confirmation of Rubella within 4 Days of Rash Onset: Comparison of Rubella Virus RNA Detection in Oral Fluid with Immunoglobulin M Detection in Serum or Oral Fluid
Authors: Abernathy Emily , Cabezas Cesar , Sun Hong , Zheng Qi , Chen Min-hsin , Castillo-Solorzano Carlos , Ortiz Ana Cecilia , Osores Fernando , Oliveira Lucia , Whittembury Alvaro , Andrus Jon K. , Helfand Rita F. , Icenogle Joseph 
Published: November 2008

ABSTRACT
Rubella virus infection is typically diagnosed by the identification of rubella virus-specific immunoglobulin M (IgM) antibodies in serum, but approximately 50% of serum samples from rubella cases collected on the day of rash onset are negative for rubella virus-specific IgM. The ability to detect IgM in sera and oral fluids was compared with the ability to detect rubella virus RNA in oral fluids by reverse transcription-PCR (RT-PCR) by using paired samples taken within the first 4 days after rash onset from suspected rubella cases during an outbreak in Perú. Sera were tested for IgM by both indirect and capture enzyme immunoassays (EIAs), and oral fluids were tested for IgM by a capture EIA. Tests for IgM in serum were more sensitive for the confirmation of rubella than the test for IgM in oral fluid during the 4 days after rash onset. RT-PCR confirmed more suspected cases than serum IgM tests on days 1 and 2 after rash onset. The methods confirmed approximately the same number of cases on days 3 and 4 after rash onset. However, a few cases were detected by serum IgM tests but not by RT-PCR even on the day of rash onset. Nine RT-PCR-positive oral fluid specimens were shown to contain rubella virus sequences of genotype 1C. In summary, RT-PCR testing of oral fluid confirmed more rubella cases than IgM testing of either serum or oral fluid samples collected in the first 2 days after rash onset; the maximum number of confirmations of rubella cases was obtained by combining RT-PCR and serology testing.
Cryptosporidium
Genotype and Subtype Distribution in Raw Wastewater in Shanghai, China: Evidence for Possible Unique
Cryptosporidium hominis
Transmission
Authors: Feng Yaoyu , Li Na , Duan Liping , Xiao Lihua 
Published: November 2008

ABSTRACT

To identify the genotype and subtype distributions of
Cryptosporidium
oocysts in domestic wastewater in Shanghai, China, and to facilitate the characterization of the endemic transmission of cryptosporidiosis, raw domestic wastewater samples were collected from four wastewater treatment plants in Shanghai, China, from December 2006 to April 2007. Genotypes of
Cryptosporidium
species were detected based on PCR-restriction fragment length polymorphism and sequence analyses of the small-subunit rRNA gene. Samples that contained
Cryptosporidium hominis
were further subtyped by DNA sequencing of the 60-kDa glycoprotein gene. Among a total of 90 samples analyzed, 63 were PCR positive, 10 of which had mixed genotypes. Fifty-nine (93.7%) of the PCR-positive samples had
C. hominis
, and 7 (11.1%) had
C. meleagridis
. The other seven
Cryptosporidium
species/genotypes identified included
C. baileyi
,
C. parvum
,
C. suis
,
C. muris
, rat genotype, avian genotype III, and a novel genotype. Forty-seven of the 59
C. hominis
-positive samples were successfully subtyped, with 29 having subtype family Ib and the remaining belonging to subtype families Ia, Id, Ie, and If. The three Ib subtypes identified, IbA19G2, IbA20G2, and IbA21G2, were very different from the two common Ib subtypes (IbA9G3 and IbA10G2) found in other areas of the world. Likewise, the Ie subtype IeA12G3T3 was also different from the common IeA11G3T3 subtype. Thus, the presence of multiple subtype families and unique Ib, Ie, and If subtypes indicates that there might be endemic transmission of cryptosporidiosis in the study area and that
C. hominis
populations there might be very different from those in other areas.
Pre-P Is a Secreted Glycoprotein Encoded as an N-Terminal Extension of the Duck Hepatitis B Virus Polymerase Gene
Authors: Cao Feng , Scougall Catherine A. , Jilbert Allison R. , Tavis John E. 
Published: November 2008

ABSTRACT
The duck hepatitis B virus (DHBV) pregenomic RNA is a bicistronic mRNA encoding the core and polymerase proteins. Thirteen AUGs (C2 to C14) and 10 stop codons (S1 to S10) are located between the C1 AUG for the core protein and the P1 AUG that initiates polymerase translation. We previously found that the translation of the DHBV polymerase is initiated by ribosomal shunting. Here, we assessed the biosynthetic events after shunting. Translation of the polymerase open reading frame was found to initiate at the C13, C14, and P1 AUGs. Initiation at the C13 AUG occurred through ribosomal shunting because translation from this codon was cap dependent but was insensitive to blocking ribosomal scanning internally in the message. C13 and C14 are in frame with P1, and translation from these upstream start codons led to the production of larger isoforms of P. We named these isoforms “pre-P” by analogy to the pre-C and pre-S regions of the core and surface antigen open reading frames. Pre-P was produced in DHBV16 and AusDHBV-infected duck liver and was predicted to exist in 80% of avian hepadnavirus strains. Pre-P was not encapsidated into DHBV core particles, and the viable strain DHBV3 cannot make pre-P, so it is not essential for viral replication. Surprisingly, we found that pre-P is an N-linked glycoprotein that is secreted into the medium of cultured cells. These data indicate that DHBV produces an additional protein that has not been previously reported. Identifying the role of pre-P may improve our understanding of the biology of DHBV infection.