bluuebunny/crossref_metadata_2025 huggingface dataset:
High prevalence of hepatitis C virus infection among noninjecting drug users: association with sharing the inhalation implements of crack
Authors: Macías Juan , Palacios Rosa B. , Claro Evangelina , Vargas Julio , Vergara Salvador , Mira José A. , Merchante Nicolás , Corzo Juan E. , Pineda Juan A.
Published: August 2010

Background: Most of the prevalent cases of hepatitis C virus (HCV) infection are attributable to intravenous drug using. However, a substantial number of individuals, particularly noninjecting drug users (NIDU), report no identifiable source of HCV exposure. This may be interpreted as inaccurate reporting of past intravenous exposure or as the presence of an unidentified source of HCV infection. Because of this, we evaluated the prevalence of and factors associated with HCV infection among NIDU.

Methods: One hundred and eighty‐two individuals who were attended from 2003 to 2004 in a drug addiction facility because of noninjecting drug use were included.

Results: HCV infection was detected in 23 (12.6%) participants. Sharing the inhalation tube of crack cocaine [adjusted odds ratio (AOR) 3.6, 95% confidence interval (CI) 1.3–9.8, P=0.01], presence of tattoos (AOR 3.5, 95% CI 1.3–9.1, P=0.02) and age ≥34 years (AOR 3.9, 95% CI 1.3–11.6, P=0.01) 3.9 were independently associated with HCV infection.

Conclusion: The prevalence of HCV infection in NIDU is higher than in general population. HCV infection is more likely among older drug users, those with tattoos and crack cocaine users that share the inhalation implements.
Chemopreventive effect of selenium and Chinese medicinal herbs on N‐nitrosobis(2‐oxopropyl)amine‐induced hepatocellular carcinoma in Syrian hamsters
Authors: Lee Chang‐Yin , Hsu Yi‐Chao , Wang Jir‐You , Chen Chien‐Chih , Chiu Jen‐Hwey
Published: August 2010

Background/Aims: Oxidative DNA damage by reactive oxygen species is involved in the process of liver carcinogenesis. To test the hypothesis that a remedy containing Scutellaria baicalensis Georgi (Sb) and Bupleurum scorzonerifolfium Willd (Bs) (Sb/Bs remedy) modulates hepatic neoplastic growth, BOP (N‐nitrosobis(2‐oxopropyl)amine)‐induced liver cancers in hamsters were established.

Methods: Parameters such as survival rate, tumour area, tumour foci, 8‐hydroxydeoxyguanosine (8‐OHdG), caspase‐3, transforming growth factor (TGF‐β1) and tumour necrosis factor‐α (TNF‐α) were measured after Sb/Bs remedy treatment during BOP‐induced carcinogenesis.

Results: The results showed that the Sb/Bs remedy and its constituents Sb and Bs suppressed the tumour area in BOP‐induced liver tumours. Because selenium (Sel) is toxic at a high dose (10 mg/kg), with a low survival rate (0%), the combination of Sb/Bs remedy and low‐dose Sel (1 mg/kg) was found to decrease the tumour area and the number of tumour foci while increasing serum TNF‐α and TGF‐β1, but not IL‐6 levels. Besides, the Sb/Bs remedy, when combined with low‐dose Sel, not only decreased the expression of 8‐OHdG and increased caspase‐3 expression within the glutathione S‐transferase placental form‐positive tumour foci but also increased tumour apoptosis in BOP‐induced hamsters.

Conclusions: We conclude that low‐dose Sel has a chemoprevention effect on BOP‐induced liver tumours and such an effect was more enhanced when combined with Sb/Bs treatment.
Hepatocellular carcinoma incidence trends in Canada: analysis by birth cohort and period of diagnosis
Authors: Pocobelli Gaia , Cook Linda S. , Brant Rollin , Lee Samuel S.
Published: August 2010

Background and Aims: We examined birth cohort and calendar period trends in hepatocellular carcinoma (HCC) incidence in Canada (1976–2000). We also projected HCC incidence rates through 2015.

Patients and methods: Data were obtained from the Canadian Cancer Registry on all cases of HCC diagnosed among persons aged 20 years and older in Canada from 1976 to 2000 and was used to describe trends in HCC incidence rates.

Results: We found that age‐adjusted HCC incidence rates increased faster in males compared with females, 3.4% per year [95% confidence interval (CI): 3.0–3.8%] vs 2.2% per year (95% CI: 1.5–2.8%). An increasing birth cohort trend accelerated among males around the 1940 birth cohort and decelerated among females around the 1935 birth cohort. For calendar period trends, the increasing HCC risk was relatively constant over time among males whereas there was an acceleration in HCC risk around 1988 among females. Age‐adjusted HCC incidence rates were projected to increase 73% in males and 28% in females from 1996 to 2015.

Conclusions: Our results suggest that HCC incidence rates will continue to increase in Canada during the next decade as persons born in more recent birth cohorts, who face a relatively greater risk for HCC, age.
Usefulness of surveillance programmes for early diagnosis of hepatocellular carcinoma in clinical practice
Authors: Pascual Sonia , Irurzun Javier , Zapater Pedro , Such José , Sempere Laura , Carnicer Fernando , Palazón Jose María , De La Iglesia Pedro , Gil Santiago , De España Francisco , Perez‐Mateo Miguel
Published: August 2010

Background/Aims: Surveillance programmes (SPs) for hepatocellular carcinoma (HCC) in patients with cirrhosis intend to diagnose the tumour in its early stages when an effective therapy can be applied. The aims of this study have been to compare the survival of patients with HCC being diagnosed or not in SPs, and to establish a more accurate profile of the best target population.

Methods: From January 1996 to June 2005, 290 patients with HCC were included. The relationship between being diagnosed or not in an SP and survival has been analysed in a univariate analysis. Pretreatment variables found to be significant predictors of survival in univariate analysis were included in a multivariate analysis.

Results: The mean survival for patients diagnosed in SPs (27 months, 16.6–37.4) was significantly longer than in patients being diagnosed out of these programmes (6 months, 2.6–9.4) (P=0.001). Child–Pugh class A [β 1.4, 95% confidence interval (CI) 1.14–1.78; P=0.0002] and being diagnosed in SPs (β 0.4, 95% CI 0.3–0.6; P=0.0003) became the only independent predictive factors of longer survival.

Conclusions: SPs for HCC allow the detection of small tumours and the application of intention‐to‐cure therapies, which improves survival. However, these programmes do not improve prognosis in patients with advanced cirrhosis.
Hepatic venous pressure gradient as a predictor of fibrosis in chronic liver disease because of hepatitis B virus
Authors: Kumar Manoj , Kumar Ashish , Hissar Syed , Jain Pankaj , Rastogi Archana , Kumar Deepak , Sakhuja Puja , Sarin Shiv K.
Published: August 2010

Background: Liver biopsy has been considered to be a gold standard for assessing hepatic fibrosis. Sample variability, interobserver variability and step‐wise evaluation limit its use. Hepatic venous pressure gradient (HVPG) correlates with hepatic fibrosis in chronic liver disease (CLD) because of hepatitis C.

Aim: To evaluate the utility of HVPG for assessing hepatic fibrosis in patients with hepatitis B virus (HBV)‐related CLD.

Patients and Methods: Sixty‐one patients with HBV‐related CLD who underwent both liver biopsy and hepatic haemodynamic studies were studied.

Results: Forty‐nine (80.3%) patients had clinically significant portal hypertension (PHT) (HVPG≥10 mmHg), 39 (63.9%) severe PHT (i.e. HVPG≥12 mmHg), six (9.8%) HVPG≤5 mmHg and another six (9.8%) had preclinical PHT (i.e. HVPG>5 but <10 mmHg). A positive correlation between HVPG and fibrosis score was found (r=0.436, P<0.001). In patients with HVPG<10 or <12 mmHg there was a significant correlation with fibrosis score (r=0.603, P=0.029 and r=0.887, P<0.001 respectively). A positive correlation also existed in patients with HVPG≥10 mmHg and in patients with HVPG≥12 mmHg (r=0.512, P≤0.001 and r=0.543, P<0.001 respectively). Receiver operating characteristic curve of HVPG for the prediction of advanced fibrosis (stage≥3) had an area under curve of 0.906. HVPG value above 13.0 mmHg had a sensitivity of 79% and a specificity of 89% for predicting advanced fibrosis on histology.

Conclusions: HVPG correlates well with the degree of histological fibrosis in patients with HBV‐related CLD.
Natural history and prognostic factors of primary biliary cirrhosis in Taiwan: a follow‐up study up to 18 years
Authors: Su Chien‐Wei , Hung Hung‐Hsu , Huo Teh‐Ia , Huang Yi‐Hsiang , Li Chung‐Pin , Lin Han‐Chieh , Lee Pui‐Ching , Lee Shou‐Dong , Wu Jaw‐Ching
Published: August 2010

Purpose: The natural history of primary biliary cirrhosis (PBC) has been little studied in Asia. We conducted a Taiwanese cohort study on the natural history of PBC and analysed the prognostic factors.

Methods: This study enrolled 96 consecutive PBC patients between 1985 and 2006 to evaluate the baseline characteristics and outcomes.

Results: There were 74 females and 22 males. Eighty‐five were positive for antimitochondrial antibodies in sera, and 11 were negative. The clinical manifestations and prognosis were similar between these two groups. In a median follow‐up of 47.5±55.8 months, 27 patients died. Multivariate analysis indicated that the independent prognostic factors were serum albumin (P=0.021), creatinine (P=0.033) and ursodeoxycholic acid treatment (P=0.008). Besides, 42 patients developed adverse outcomes. Albumin (P<0.001), bilirubin (P=0.019) and prothrombin time (PT) (P=0.010) were significant factors. Moreover, a Mayo risk score <5, a Model for End‐Stage Liver Disease (MELD) score <6, a Child–Pugh stage A and early liver histology were associated with favourable outcomes.

Conclusion: Serum albumin, bilirubin and PT were independent prognostic factors of adverse outcomes for Taiwanese PBC patients. Besides, the Mayo risk score, the MELD score, the Child–Pugh stage and liver histology were also validated to predict survival.
Disruption of connective tissue growth factor by short hairpin RNA inhibits collagen synthesis and extracellular matrix secretion in hepatic stellate cells
Authors: Yuhua Zhu , Wanhua Ren , Chenggang Sun , Jun Shi , Yanjun Wang , Chunqing Zhang
Published: August 2010

Purpose: Connective tissue growth factor (CTGF) plays a key role in the pathogenesis of liver fibrosis. This study aimed at investigating that the disruption of CTGF expression by short hairpin RNA (shRNA) could modulate the production of fibrosis‐related components in hepatic stellate HSC‐T6 cells.

Methods: Three plasmids expressing individual shRNA were constructed and transfected into HSC‐T6 cells respectively. The levels of CTGF and transforming growth factor β1 (TGF‐β1) expression were determined by reverse transcriptase‐polymerase chain reaction and Western blot assays. Furthermore, the production of collagens and extracellular matrix (ECM) proteins, including type III procollagen (PC III), type IV collagen (collagen IV), laminin (LN) and hyaluronic acid (HA) in the CTGF‐disrupted cells, were analysed by radioimmunoassay.

Results: Following transfection with the pEGFP‐CTGFshRNA1, the expression of CTGF was disrupted in HSC‐T6 cells. While the knockdown of CTGF expression failed to modulate the expression of TGF‐β1, it did significantly reduce the production of PC III, collagen IV, LN and HA by HSC‐T6 cells.

Conclusion: Our data suggest that shRNA‐mediated disruption of CTGF expression can attenuate ECM synthesis. Potentially, our findings may aid in the design of a CTGF‐based new therapy for treatment of hepatic fibrosis.
Serum levels of soluble vascular cell adhesion molecule are related to hyperdynamic circulation in patients with liver cirrhosis
Authors: Lo Iacono Oreste , Rincón Diego , Hernando Ana , Ripoll Cristina , Catalina Maria Vega , Salcedo Magdalena , Clemente Gerardo , Gomez Judith , Nuñez Oscar , Matilla Ana , Bañares Rafael
Published: August 2010

Background: In patients with liver cirrhosis, serum levels of soluble vascular cell adhesion molecule‐1 (sVCAM‐1) have been associated with increasing fibrosis and are related to angiogenesis.

Aim: To assess the possible correlation between sVCAM‐1 and splanchnic and systemic haemodynamic and clinical staging of cirrhotic patients.

Methods: We assessed, using immunoassays, the serum levels of sVCAM‐1, in the peripheral and hepatic vein, in all consecutive patients with liver cirrhosis, who underwent a haemodynamic study as part of its routine clinical work‐up.

Results: We studied 86 patients [61 M/25 F; age 51.1 (8.3) years] with alcoholic (31) or viral (HBV:6, HCV:49) cirrhosis, 10 of them with hepatocellular carcinoma (Milan criteria). The mean follow‐up was 391(187) days; 29 patients died or underwent transplantion during follow‐up. A strong correlation in serum levels of sVCAM‐1 was observed between the peripheral and the hepatic vein (r=0.8; P=0.0001). There was no correlation between levels of sVCAM‐1 and hepatic venous pressure gradient. At univariate analysis, sVCAM‐1 was inversely related with mean arterial pressure (r=−0.292; P=0.007), systemic vascular resistance (SVR) (r=−0.37; P=0.005) and serum sodium levels (r=−0.326; P=0.002). In multivariate linear regression only SVR remained as an independent variable associated to sVCAM‐1. A correlation of sVCAM‐1 with Child–Pugh scores, model for end‐stage liver disease (MELD) and the clinical stage proposed in the Baveno IV consensus conference was also observed. Finally, patients who died or underwent transplantion during follow‐up had significantly greater values of sVCAM‐1 at baseline than those who did not [3505(1329) vs. 2488(1208) P=0.001].

Conclusion: This study supports a potential role of sVCAM‐1 as a marker of hyperdynamic circulation, closely related to the different stage of liver cirrhosis.
Evaluating the accuracy and increasing the reliable diagnosis rate of blood tests for liver fibrosis in chronic hepatitis C
Authors: Calès Paul , De Ledinghen Victor , Halfon Philippe , Bacq Yannick , Leroy Vincent , Boursier Jérôme , Foucher Juliette , Bourlière Marc , De Muret Anne , Sturm Nathalie , Hunault Gilles , Oberti Frédéric
Published: August 2010

Background: The reliable diagnosis rate of diagnostic tests is provided by their intervals with acceptable accuracy (e.g. ≥90%) where a liver biopsy can be avoided.

Aims: To evaluate the overall accuracy and improve the reliable diagnosis rates of blood tests for significant liver fibrosis.

Methods: Five blood tests were compared with Metavir fibrosis (F) staging in 1056 patients with chronic hepatitis C.

Results: Area under the receiver operating characteristics (F0‐1 vs. F2‐4) were: FibroMeter: 0.853, Fibrotest: 0.811, Fib‐4: 0.799, aspartate aminotransferase to platelet ratio index (APRI): 0.786 and Hepascore: 0.784 (P<10−3 between tests). The reliable diagnosis rates based on two traditional intervals defined by thresholds ≥90% of negative predictive values (NPV) and positive predictive values (PPV), diagnosing F0/1 and F2/3/4, respectively, were: FibroMeter: 43.5%, APRI: 19.6%, Fibrotest: 17.1%, Hepascore: 3.9%, Fib‐4: 1.7% (P<10−3). By dividing the indeterminate interval by the diagnostic cut‐off, two new intervals could be diagnosed reliably: F1/2 and F1/2/3. Accordingly, the reliable diagnosis rate was increased, e.g. FibroMeter: 75.5% (accuracy: 89.5%) with three intervals (F0/1, F1/2, F2/3/4). It was possible to further increase this rate by using the more exportable 90% sensitivity/specificity thresholds, e.g. FibroMeter: 90.2% (accuracy: 86.4%). By using the four intervals, the reliable diagnosis rate was 100% (accuracy: 89.5% with predictive value (PV) and 87.5% with sensitivity/specificity).

Conclusion: Reliable diagnosis is a diagnostic index devoted to clinical practice. Its rate can be increased by creating new intervals between diagnostic cut‐off and 90% PVs or sensitivity/specificity thresholds. This increased the overall accuracy from 78.1 to 89.5% and reduced the need for a liver biopsy from 56.5 to 0% with the most accurate test.
Adult liver transplant survey: policies towards eligibility criteria in Canada and the United States 2007
Authors: Kroeker Karen I. , Bain Vincent G. , Shaw‐Stiffel Thomas , Fong Tse‐Ling , Yoshida Eric M.
Published: August 2010

Goals:To assess the current practice patterns of liver transplant centres in Canada and the USA regarding transplant eligibility.

Background:Liver transplantation is an evolving field and today remains the only life‐sustaining treatment for end‐stage liver disease. Issues of allocation and transplant eligibility are important factors in the ethical practice of medicine.

Study:Questionnaires were mailed to liver transplant programme directors in Canada and the USA inquiring about current practices regarding recipient eligibility.

Results:This study demonstrates that there is consensus in the use of other eligibility criteria, including non‐compliance, social status, abstinence from alcohol and methadone and cocaine use. Interestingly, literature is lacking to support the use of these parameters as eligibility criteria with the exception of alcohol. There is a lack in consensus regarding marijuana use, human immunodeficiency virus status, ability to accept blood transfusions and prisoner status. The literature suggests that liver transplantation in select patients who refuse blood transfusions results in good outcomes.

Conclusions:Important decisions regarding transplant eligibility still have to be made empirically in the absence of scientific literature about various social issues. While consensus among transplant programmes is useful, it is important that we continue to use the evidence in the literature to revise these eligibility criteria, keeping in mind ethical principles applied to the access and allocation of a scarce resource.
Bacterial translocation increases phagocytic activity of polymorphonuclear leucocytes in portal hypertension: priming independent of liver cirrhosis
Authors: Neugebauer Hermann , Hartmann Pia , Krenn Sebastian , Glück Thomas , Schölmerich Jürgen , Straub Rainer , Wiest Reiner
Published: August 2010

Aim: Bacterial translocation (BT) to mesenteric lymph nodes (MLN) in cirrhosis has been linked to impaired host defence. Phagocytosis by polymorphonuclear leucocytes (PMNLs) is the primary event in the killing of bacteria but has not been investigated in relation to the presence of BT.

Methods: Mesenteric lymph nodes were harvested sterile and assessed for BT by culture techniques. Study groups included ascitic cirrhotic rats (LC), healthy controls (Con) as well as portal‐vein‐ligated (PVL) rats 2 days (acute PVL with and without norfloxacin) or 3 weeks after surgery (chronic PVL). PMNLs were isolated from systemic blood and the capacity to phagocytose opsonized Escherichia coli was evaluated by FACS analysis.

Results: No BT was observed in Con and chronic PVL animals but 11/20 LC (55%) and six out of six acute PVL (100%) presented with BT. In the presence of BT, PMNL from PVL as well as LC rats showed significantly increased phagocytic activity as compared with controls. In contrast, PMNL from animals without BT, whether PVL or LC, exhibited phagocytic activity similar to those from control rats. The number of PMNLs involved in the phagocytic process was significantly increased only in portal‐hypertensive rats with but not without BT as compared with controls. Norfloxacin did prevent BT in acute PVL animals, thereby correcting the increase in phagocytic capacity in PMNL.

Conclusions: Cirrhosis per se is not associated with alterations of the phagocytic capacity of PMNL. The occurrence of BT, however, increases the phagocytic capacity of PMNL, being observed likewise in prehepatic portal hypertension, indicating an in vivo‘priming’ of PMNL by BT independent of cirrhosis.
Disease progression and the risk factor analysis for chronic hepatitis C
Authors: Sinn Dong Hyun , Paik Seung Woon , Kang Pung , Kil Jae Sook , Park Sang Un , Lee So‐Young , Song Soon Mi , Gwak Geum‐Youn , Choi Moon Seok , Lee Joon Hyoek , Koh Kwang Cheol , Yoo Byung Chul
Published: August 2010

Background/Aims:The present study aimed to assess the incidence of advanced cirrhotic complications and to identify the risk factors associated with such complications in chronic hepatitis C.

Methods:The data of 1137 chronic hepatitis C patients were retrospectively reviewed. We analysed the incidence rate and risk factors for ‘disease progression’, as defined by the occurrence of an increase of at least 2 points in the Child–Pugh score, oesophageal/gastric variceal bleeding, spontaneous bacterial peritonitis, hepatic encephalopathy, death related to liver disease or development of hepatocellular carcinoma (HCC).

Results:Of the 1137 patients enrolled for analysis, 490 patients received antiviral treatment. The overall annual incidence rate of disease progression was 0.8 and 3.7% for patients with and without antihepatitis C virus (anti‐HCV) therapy respectively. The development of HCC was the most common cause of disease progression. In patients with anti‐HCV therapy, treatment response, platelet level and aspartate aminotranferase:platelet ratio index (APRI) were independent factors associated with disease progression. For those without anti‐HCV therapy, older age, male sex, diabetes, platelet level and APRI were independent factors for disease progression. APRI was strongest predictor for disease progression.

Conclusions:The present study demonstrated that the development of HCC was the most common cause of disease progression, and we also identified the risk factors associated with disease progression. Thus, patients at such risks need close monitoring for disease progression, and especially for detecting HCC. Moreover, the active application of antiviral therapy and efforts to improve the antiviral response are required.
Price undertakings, VERs, and foreign direct investment: the case of foreign rivalry
Authors: Ishikawa Jota , Miyagiwa Kaz
Published: August 2010

Abstract.  Antidumping (AD) petitions are often withdrawn in favour of voluntary export restraints (VERs) and price undertakings. This paper compares these policy options in the presence of protection‐jumping foreign direct investment (FDI), with special emphasis on rivalry between foreign firms. We show that a VER is less likely to induce FDI than a price undertaking or AD. As a result, by settling AD cases with VER agreements, the importing country can pursue a more protectionist policy without triggering FDI. In this sense the GATT ban on VERs following the proliferation of AD uses was a sensible decision.
Why is the rate of single‐parenthood lower in Canada than in the U.S.? A dynamic equilibrium analysis of welfare policies
Authors: Guner Nezih , Knowles John
Published: August 2010

Abstract A critical question in the design of welfare policies is whether to target aid according to household composition, as was done in the U.S. under the Aid to Families with Dependent Children (AFDC) program, or to rely exclusively on means‐testing, as in Canada. Restricting aid to single mothers, for instance, has the potential to distort behaviour along three demographic margins: marriage, fertility, and divorce. We contrast the Canadian and the U.S. policies within an equilibrium model of household formation and human capital investment on children. Policy differences we consider are eligibility, dependence of transfers on the number of children, and generosity of transfers. Our simulations indicate that the policy differences can account for the higher rate of single‐parenthood in the U.S. They also show that Canadian welfare policy is more effective for fostering human capital accumulation among children from poor families. Interestingly, a majority of agents in our benchmark economy prefers a welfare system that targets single mothers (as the U.S. system does), yet (unlike the U.S. system) does not make transfers dependent on the number of children.
Rational truth‐avoidance and self‐esteem
Authors: Andolfatto David , Mongrain Steeve , Myers Gordon
Published: August 2010

Abstract We assume that people have beliefs about their abilities that generate self‐esteem, and that self‐esteem is valued intrinsically. Individuals face two choices; one of which strictly dominates the other in a pecuniary sense, but necessarily involves gathering information concerning their ability. We lay out the circumstances under which an individual may find it rational to reject the dominant choice, an act that, in psychology is described as avoiding the situation. We then go on to show that the incentive to avoid the truth is increasing in income/wealth and decreasing in self‐esteem, the perceived accuracy of one's self‐assessment, and the role that luck plays in generating opportunities.
Trade costs, wage rates, technologies, and reverse imports
Authors: Ishikawa Jota , Komoriya Yoshimasa
Published: August 2010

Abstract This paper explores the effects of transport costs, tariffs, and foreign wage rates on the domestic economy in the presence of reverse imports, with special emphasis on inter‐firm cost asymmetry in an international oligopoly model. To serve the domestic market, a foreign firm produces in the foreign country, while two domestic firms produce either at home or abroad. Surprisingly, an increase in the foreign wage rate may increase the profits of a firm producing in the foreign country. Even if all firms produce in the foreign country, an increase in the foreign wage rate may improve domestic welfare.
Tariff effects on MNC decisions to engage in intra‐firm and arm's‐length trade
Authors: Feinberg Susan E. , Keane Michael P.
Published: August 2010

Abstract Using confidential firm‐level data from the Bureau of Economic Analysis (BEA) on activities of U.S. multinational corporations (MNCs) and their Canadian affiliates, we study the dramatic growth of intra‐firm and arm's‐length U.S.‐Canada trade over the 1984–95 period. We find that decisions to engage in intra‐firm and arm's‐length trade are essentially unrelated to tariff and transport cost reductions over this sample period. Thus, we find that the increase in trade occurred almost entirely on the intensive rather than the extensive margin. This is consistent with case study evidence in Keane and Feinberg (2006), where MNC executives consistently indicate that the modest tariff reductions of the 1984–95 period were not sufficient to justify fixed costs of overhauling international supply chains. Our results have important implications for recent influential models of international trade that rely on sensitivity of intra‐firm trade to tariffs at the extensive margin to explain how small tariff declines could have led to the explosion of intra‐firm trade since the 1980s. We also find that initial conditions (i.e., 1983 tariffs) are uncorrelated with whether firms engaged in intra‐firm or arm's‐length trade activity at the start of the sample period. This result is surprising as it implies that firms/industries with a greater propensity to engage in trade were not, in general, successful at lobbying for more favourable tariff treatment.
International trade, flexible manufacturing, and outsourcing
Authors: Eckel Carsten
Published: August 2010

Abstract This study analyzes the impact of opening up markets on the diffusion of flexible manufacturing in a general equilibrium framework. With flexible manufacturing, suppliers can service a range of downstream industries and do not have to be concerned about being held up. Instead, the vertical structure is determined by the trade‐off between economies of scale in flexible manufacturing and product specificity of in‐house production. The analysis derives a number of testable predictions with regard to firm size and productivity measures and shows that globalization can lead to a consolidation in upstream markets, lower real wages, and reduce welfare.
Entry cost, the Tobin tax, and noise trading in the foreign exchange market
Authors: Shi Kang , Xu Juanyi
Published: August 2010

Abstract Two types of policy have been proposed to eliminate noise trading in the foreign exchange market: increasing the entry cost or imposing a ‘Tobin tax’ type of transaction tax. In this paper, we endogenize entry decisions of both informed traders and noise traders and show that these policies may be ineffective in reducing exchange rate volatility. This is because these policies will discourage the entry of all traders, so they may not change the relative ratio of traders, or they may affect informed traders disproportionately more, which increases the relative ratio of noise traders and exchange rate volatility.
Understanding the wage patterns of Canadian less skilled workers: the role of implicit contracts
Authors: Green David A. , Townsend James
Published: August 2010

Abstract We examine the wage patterns of Canadian less skilled male workers over the last quarter‐century by organizing workers into job entry cohorts. We find entry wages for successive cohorts declined until 1997 and then began to recover. Wage profiles steepened for cohorts entering after 1997, but not for cohorts entering in the 1980s – a period when start wages were relatively high. We argue that these patterns are consistent with a model of implicit contracts with recontracting in which a worker's current wage is determined by the best labour market conditions experienced during the current job spell.
“This Great Emptiness We Are Feeling”: Toward a Decolonization of Schooling in Simunurwa, Colombia
Authors: Murillo Luz A.
Published: August 2010

This article examines the decolonization of schooling in an Arhuaco community in the Sierra Nevada de Santa Marta region of Colombia. Interweaving ethnographic description with accounts of key events that took place between 1915 and 2006, I trace the community's struggle to develop an Indigenous school capable of appropriating Western forms of knowledge while retaining Indigenous practices and beliefs. I describe how Indigenous educators incorporate local forms of knowledge into schooling, and how these are presented and understood relative to the structures and discourses of the colonized school. Using the concepts of “translocality” and “transculturation,” I frame this discussion of the struggle for educational autonomy within broader efforts to decolonize knowledge and epistemologies inherited from European traditions and the Colombian state. I argue that educators have transformed the school from a colonizing space to one in which Indigenous people contest and negotiate, via practices of cultural and linguistic revitalization, the state violence that threatens to surround them. [Arhuaco, Colombia, decolonization, Indigenous education, local knowledge, transculturation, translocality]
PLANNING AQUACULTURE DEVELOPMENT: THE FIRST TIME IS ALWAYS THE HARDEST
Authors: Corbin John S. , Gibson Richard T.
Published: August 2010

United States and world aquaculture production has been increasing rapidly in recent years. The State of Hawaii recognized the potential benefits from expanded aquaculture research and commercial activities and has devoted more than two years in preparing the nation' first comprehensive state‐wide aquaculture development plan. This paper shares the Hawaii planning experience and outlines the procedures, methodology and philosophies, with emphasis on issues which may be relevant to other aquaculture planning efforts. In particular, the following areas are addressed: 1) the initial scoping of the planning process, 2) staffing, 3) preliminary analysis of the data acquisition task, 4) the assessments, 5) formulation of the guidelines for development, and 6) implementation philosophies, strategies and tactics. Hawaii' approach imparts a pragmatic, conservative, step‐wise course for aquaculture development that recognizes the State' finite financial resources while working to achieve the best possible cost/benefit ratio. However, although appearing conservative, it casts State government in the novel role of a strong advocate of aquaculture progres.
VENTURE ANALYSES FOR A PROPOSED COMMERCIAL WASTE HEAT AQUACULTURE FACILITY
Authors: Guerra Carlos R. , Resh Robert E. , Godfriaux Bruce L. , Stephens Carol A.
Published: August 2010

Data on the development and operating costs for a proposed commercial waste heat aquaculture facility dedicated to culture two species on a diseasonal sequence are presented in this paper. The facility would be located at the Mercer Generating Station, a coal‐fired electric power plant, near Trenton, New Jersey.

The concept of reliability indices associated with each of the principal cost and income elements of the proposed aquaculture facility is also introduced. Plots of Return‐on‐Investment vs economic factors and reliability indices are used to depict the venture profitability and confidence of success expected with some of the aquaculture species being studied and the production plans under consideration.

Rainbow trout (Salmo gairdneri [Richardson]) is the principal income‐producing species at the present time and channel catfish (Ictalurus punctatus [Rafinesque]) is being tested as the warm weather species. High density culture experiments with freshwater shrimp (Macrobrachium rosenbergii [de Man]) have not met the criteria for profitability to date; however, because of the market potential for this species, additional studies are underway.

Return‐on‐investment analyses were run by varying the principal parameters determining the profitability of a commercial venture. These included the culture species, production density, plant size and useful life, processing facilities, sale price of products and type of financing for venture.

The project is jointly sponsored by the National Science Foundation (Division of Problem Focused Research Applications) and PSE&G Company. The venture analyses are based on experimental studies being conducted by Trenton State College and Rutgers University.
AUBURN UNIVERSITY' PHILOSOPHY AND STRATEGY FOR INTERNATIONAL AQUACULTURAL DEVELOPMENT AND TECHNOLOGY TRANSFER
Authors: Moss D. D. , Grover J. H. , Schmittou H. R. , Shell E. W. , Lichtkoppler F. L.
Published: August 2010

The International Center for Aquaculture at Auburn University has been involved in international aquaculture development in a formal way for approximately 12 years. It has been or is participating in aquaculture development programs in Thailand, Philippines, Indonesia, Nigeria, Brazil, El Salvador, Panama, Colombia, Honduras and Jamaica by providing the services of 18 professional staff who have contributed a total of 56 years of long‐term advisory services. In addition, the Center has provided advisory services on a short‐term basis; 50 individual staff members have made 240 country visits, representing 57 different countries in which the staff contributed 4,504 days of overseas work.

Auburn' philosophy in aquaculture development, frequently referred to as the “oil spot phenomenon,” is to create a center of excellence in aquaculture in which established fish cultural techniques are tested under local conditions, modified as needed, retested to prove the methodology and subsequently extended to production areas adjacent to the aquaculture center. As extension capabilities are developed and production methodology improved, the aquaculture technology gradually spreads to areas more distant from the center, much like a drop of oil spreads after falling upon a water surface. Auburn' strategy to achieve an aquaculture “oil spot” of sufficient magnitude that will permit its diffusion is discussed.
INDUCTION OF LARVAL ABALONE SETTLING AND METAMORPHOSIS BY γ‐AMINOBUTYRIC ACID AND ITS CONGENERS FROM CRUSTOSE RED ALGAE: II: APPLICATIONS TO CULTIVATION, SEED‐PRODUCTION AND BIOASSAYS; PRINCIPAL CAUSES OF MORTALITY AND INTERFERENCE
Authors: Morse Daniel E. , Hooker Neal , Jensen Lloyd , Duncan Helen
Published: August 2010

Costly and extensive early post‐larval mortality of Haliotis species in cultivation results, in part, from a delay in normal development. This suggests that naturally required morphogenetic inducing substances may be lacking from certain intensive cultivation systems currently in use in the emerging mariculture industry.

We have found recently that chemical substances in certain crustose red algae (including species of Lithothamnium, Lithophyllum and Hildenbrandia) provide exogenous physiological triggers which induce normal substrate‐specific “recruitment,” settling and the onset of metamorphosis of planktonic abalone veliger larvae. Of these, γ‐aminobutyric acid (“GABA”), a simple amino acid readily and inexpensively available in pure form, conveniently can be used to induce rapid and synchronous settling and metamorphosis of competent abalone veligers, on virtually any substrate or food source, with 100% efficiency under physiological conditions.

Simple procedures for the use of GABA‐induced settling are described for the economically efficient cultivation of abalone, the production of abalone seed, and for use in genetic breeding and engineering with these species. Procedures for use in a rapid, reliable, and highly sensitive GABA‐dependent bioassay also are described, for further analysis of physiological and water‐quality requirements of, and effects of various pollutants upon, the natural and artificial propagation of these species. Results obtained with this bioassay in quantitating the sensitivity of larval settling (and hence, reproductive success) to bacterial contamination and to trace levels of the common agricultural and industrial pollutants DDT and copper are reported. Significant predation on newly settled abalone by annelids cryptically associated with the natural red algal (recruiting) substrate also is documented.
SUBSISTENCE AQUACULTURE AND TECHNOLOGY TRANSFER AMONG DEVELOPED AND DEVELOPING COUNTRIES
Authors: Madamba Joseph C.
Published: August 2010

Subsistence‐level and small‐scale aquaculture systems dominate the aquaculture industry of most developing countires. Characterized by low material and management inputs, low level of technology, and low output, subsistence‐level aquaculture is a system of farming that gives an inadequate economic return to the operator.

It is argued that subsistence‐level and small‐scale aquaculturists must be given adequate government attention and institutional support: first, because these farming systems can be greatly improved; second, because they provide employment opportunities for the rural poor; and third, because aquaculture is a potential significant source of protein food for the poorer majority.

The status of aquaculture in several developing countries is reviewed. Small‐scale fishfarming characterized by traditional practices predominates in India, Bangladesh, Indonesia, Nepal, Thailand, Malaysia, and the Philippines. The pattern is similar in some African countries like Nigeria, Kenya, and the Sudan.

A socioeconomic profile of the small fishfarmer is drawn. Aside from his low level of application of production and management inputs and his low output, he is highly susceptible to the vagaries of the market. His capacity to acquire improved technology on his own is low. To augment his earnings, he works in non‐aquaculture occupations.

The paper calls for a policy as well as a research and development bias for the subsistence fishfarmer. An aquaculture industry development support model is presented and a pilot‐scale implementation scheme of this model is described.

Finally, a mechanism is described for the transfer of local and borrowed aquaculture technology within a given country and among countries.
EXPERIMENTAL LOBSTER RANCHING IN MASSACHUSETTS
Authors: Hruby Thomas
Published: August 2010

Artificial shelters were deployed in the shallow waters of Massachusetts Bay in an attempt to stabilize and increase lobster catches. Shelters constructed with concrete‐filled tires proved to be well suited for small‐scale ranching operations. Only two people were needed to make and deploy the shelters, and the capital costs were low. The animals quickly occupied shelters on sandy bottoms but not on rocky ones, and when fish wastes were provided as food in the former habitats, an increase was noted in trap captures. However, stable populations could not be maintained in the experimental areas for the lobsters were found to be continually moving. In October and November a general offshore trend was noted and tagged lobsters moved from a depth of 10 m to approximately 20 m.
REPORT ON THE INDUCED MATURATION AND OVULATION OF MILKFISH (Chanos chanos) REARED IN TANKS1
Authors: Liao I‐Chiu , Chen Tzyy‐Ing
Published: August 2010

The milkfish (Chanos chanos [Forskal]) is one of the most important cultivation fishes in Southeast Asia. Since 1970, Tungkang Marine Laboratory (TML) has embarked on a long‐term program in broodstock maintenance and artificial propagation with the goal of supplying adequate fry for milkfish farming. In the past three years, the histological study of gonadal development and the experiment on inducing maturation and ovulation of adult milkfish with hormonal injections were carried out. It was found that 5‐ or 6‐year‐old tank‐reared fish could reach full maturity after hormonal treatment. Sperm were always found in males with Gonadal Somatic Index (GSI) larger than 0.20, with or without treatment. All of the ovarian oocytes of three female spawners with GSI of 11.23, 8.12 and 10.70 reached mature stage after treatment, and average diameter of the eggs was 1.16, 0.94 and 1.19 mm, respectively. One female spawned naturally after one injection, and released hydrated eggs measuring 1.08 mm in diameter. However, the eggs were not fertilized.

Pituitary gland homogenates of both salmon and mullet, human chorionic gonadotropin (HCG), and Puberogen plus vitamin E used in the present experiment seemed more effective in stimulating gonadal development when ovarian oocytes were beyond the tertiary yolk stage, i.e., the oocyte sizes were larger than 0.70 mm in diameter.

Although most of the treated females failed to ovulate, they were still prospective spawners. The success of artificial propagation with tank‐reared spawners is anticipated in the near future.
RELATIONSHIPS BETWEEN GROWTH AND HYDROLOGICAL PARAMETERS FOR FED ATLANTIC CROAKER AND UNFED STRIPED MULLET
Authors: Chamberlain George W. , Strawn Kirk
Published: August 2010

Atlantic croaker (Micropogon undulatus) and striped mullet (Mugil cephalus) were cultured in cages in the intake area, at the head of the discharge canal, and at three locations in the cooling lake of a power plant near upper Galveston Bay, Texas, from 1 February 1976 to 20 August 1976 to assess the suitability of each location for mariculture. Interpretations were based on daily measurements of six hydrological parameters and survival and growth of fish. Primary sources of mortality included high effluent temperatures, abrupt changes in conductivity, and lymphocystis. Growth rates of fed Atlantic croaker were strongly related to water temperature. Regression procedures were used to develop a polynomial function to describe the parabolic relationship between growth rate of croaker and mean monthly water temperature. The curve described by this model indicated no growth at temperatures below about 13.5°C or above about 33.5°C and maximum growth near 27°C. This information might be valuable in selecting optimum locations for culture of Atlantic croaker or related fishes within thermally heterogeneous environments. Growth rates of unfed striped mullet were not related to water temperature but were linearly related to pH and dissolved oxygen, which were probably indicators of primary production. However, the growth of mullet was poor even at the most productive locations consequently, the use of unfed caged mullet to harvest phytoplankton does not seem feasible unless the primary productivity levels are considerably higher than those in our study area.
CULTURE OF FRESHWATER PRAWNS (Macrobrachium rosenbergii) USING GEOTHERMAL WASTE WATER
Authors: Johnson William C.
Published: August 2010

The farming of freshwater prawns (Macrobrachium rosenbergii) in geothermal heated water has been demonstrated to be possible in a nontropical climate. The husbandry of prawns is being done in two outdoor raceway ponds 9.1 m by 2.5 m and 29 m by 3.5 m that are 1.2 m deep. The ponds are not shielded from the ambient climate which during the winter months has recorded air temperatures as low as ‐20°C. A select brood stock is held in a small spawning building where larvae are hatched in artificial saltwater and reared to the postlarvae stage, making the facility self‐contained. This project is providing a model for potential investors to utilize the low‐temperature geothermal resources in the western United States for warm water aquaculture of a market‐size prawn.
Macrobrachium rosenbergii CULTURE IN POLYNESIA: pH CONTROL IN EXPERIMENTAL POND WATERS BY PHYTOPLANKTON LIMITATION WITH AN ALGICIDE
Authors:   AQUACOP
Published: August 2010

Macrobrachium rosenbergii ponds at the Centre Océanologique du Pacifique are subject to increases in pH exceeding 10.5 during growing experiments. The high levels of pH are responsible for mortality of prawns, especially when molting. The photosynthetic activity of dense phytoplankton blooms are primarily responsible for high pH. The algicide Clarosan (CIBA‐Geigy) was used to thin phytoplankton blooms. Experiments showed that treatments with 0.02 mg/liter result in a rapid fall in the pH. At this dose Clarosan is not deleterious to the prawns.
INTENSIVE LARVAL CULTURE OF Macrobrachium rosenbergii: A COST STUDY
Authors: AQUACOP
Published: August 2010

Pilot scale larval culture of Macrobrachium rosenbergii began in Tahiti at the end of 1976. Since then, four batches of postlarvae (2.3 millions) have been produced. Operating expenses cost was $13–35/thousands postlarvae.

Based on the results obtained from the pilot program, we can project the cost of a commercial scale hatchery producing 10 million postlarvae/year at $12/1,000. This includes construction and equipment costs. Due to the high cost of living in Tahiti, this figure would undoubtedly be lower in many other regions.
PENAEID REARED BROOD STOCK: CLOSING THE CYCLE OF P. monodon, P. stylirostris AND P. vannamei
Authors: AQUACOP
Published: August 2010

Three shrimp species, Penaeus monodon, P. stylirostris (Panama and Mexican strains) and P. vannamei have matured and spawned in captivity at the Centre Océanologique du Pacifique (COP) laboratory. The shrimp, originally stocked as juveniles or postlarvae, were reared to adult size in tanks and ponds and have completed the cycle: F3 generation for P. monodon, F2 for P. stylirostris (Panama strain) and P. vannamei and F1 for P. stylirostris (Mexican strain). Maturation occurs naturally under our rearing conditions or is induced by unilateral eyestalk ablation. Details are given on mating behavior, ovarian development, number of spawnings, egg viability and maintenance of captive brood stock. Partial results so far obtained for P. monodon and P. stylirostris clearly show a reared brood stock could sustain a commercial hatchery.
ORGAN INDICES AND BIOCHEMICAL LEVELS OF OVA FROM PENAEID SHRIMP MAINTAINED IN CAPTIVITY VERSUS THOSE CAPTURED IN THE WILD
Authors: Lawrence A. L. , Ward D. , Missler S. , Brown A. , McVey J. , Middleditch B. S.
Published: August 2010

This paper characterizes further penaeid shrimp reproduction by reporting: (1) the gonad, hepatopancreas, tail and eyestalk indices for unablated and unilateral ablated penaeid shrimp (P. setiferus) maintained in captivity versus shrimp captured in the wild; and (2) the biochemical content of spawned ova from three species of penaeid shrimp (P. setiferus, P. stylirostris and P. vannamei) obtained from wild populations and one species (P. setiferus) matured and spawned in captivity. The data indicated that (1) the dietary and environmental regimen used in this study is not optimum for reproduction of P. setiferus in captivity; (2) the hepatopancreas but not the tail muscle is directly involved in penaeid reproduction; (3) the population of P. setiferus sampled on June 2 and July 22, 1978, in the northwestern Gulf of Mexico was not at its reproductive peak; (4) the percent protein, lipid and carbohydrate content of unhatched eggs of P. setiferus, P. stylirostris and P. vannamei are very similar; and (5) biochemical analysis of the unhatched eggs and the determination of organ indices during reproduction are important parameters to obtain for understanding and evaluating penaeid reproduction in the wild and in captivity.