Predictions of fish yields and the status of the Kainji Lake fishery, 1998

Length frequency data was collected for the 6 main species from the Kainji Lake fishery for up to 16 months. Growth parameters were estimated and used for virtual - population and length based cohort analysis. The results from cohort analysis suggest that before the ban on beach seines the maximum economic yield from the fishery was overshot by 70%. Yield per recruit analysis showed that the fish are caught far below their optimum size. Fishing gears and the timing responsible for this early mortality have been identified. After the eradication of seines from the lake a 10% increase in total catch revenue can be expected from the fishery. This is equivalent to an increase in income of Naira 18,300 per annum for each fishing entrepreneur using other methods. A scenario for the regulation of cast net mesh size together with the ban of beach seines has been presented. A further increase of Naira 142 million (N25,500 per entrepreneur) can be anticipated if this is implemented by the Kainji Lake Fisheries Management and Conservation Unit. It is expected that the annual increase in fishing effort presently experienced will cause future yields to decline. The rate of the decline has been reduced by the eradication of the beach seine fishery and will further fall if the minimum mesh size for cast nets is implemented. A recommendation is made to the Kainji Lake Fisheries Management and Conservation Unit to first consolidate the beach seine ban and then to implement a ban of undersized cast nets. (PDF contains 70 pages)

Some aspects of population dynamics of juvenile hilsa shad (Tenualosa ilisha Ham.) from the Meghna river, Bangladesh

Population dynamics of the juvenile hilsa shad (Tenualosa ilisha) in the nursery ground of the Meghna River have been studied on the basis of the length cohort analysis of 8023 specimens. The growth parameters viz; asymptotic length (Lα), curvature character (K) and initial time (t0) were found to be 30.69 cm, 1.2 yrˉ¹ and 0.45 yrˉ¹ respectively. Curvature parameter indicates that jatka is a fast growth performer. The natural, fishing and total mortality were found to be 1.37 yrˉ¹, 1.41 yrˉ¹ and 2.78 yrˉ¹ respectively. Survival rate (S) was found to be 6.2%. A small difference was found between the age at first capture (Tc) and the recruitment age (Tr). Stocks of jatka seem to be overexploited and need to be conserved.

Mortality rates estimates for Metapenaeus monoceros (Fabricius) of Maputo Bay

The species Metapenaeus monoceros in Maputo Bay recruits to the fishery almost all over the year, but the main recruitment occurs over a short period of time, each year, during April-May. Growth curves were constructed by following the progression of modes over a period of time. The von Bertalanffy growth parameters were estimated as L∞=31.9 mm and K(monthly)=0.25, for males, and L∞=48.3 mm and K(monthly)=0.14, for females (Brinca and Sousa, 1984). Using data on growth and length composition of the catches, the following methods were applied to estimate mortality rates of M. monoceros: estimation of natural mortality by using approximative methods; use of c.p.u.e. data; catch curves; cohort analysis; average age and length methods.

The study of biological characteristic and population dynamic of Caspian vimba (Vimba vimba persa), in coastal waters of Caspian Sea (Mazandaran Province)

This study was conducted to determine reproduction characteristics, diet regime, age structure and population dynamics parameters of the vimba vimba persa (Pallas, 1811) in Mazandaran waters of the Caspian Sea, from October 2008 to September 2009. A total of 994 specimens were monthly collected by beach seine and cast net from six fish landings of Ramsar, Tonekabon, Chaloos, Mahmood Abad, Sari and Behshahr. Biometric characters were measured for each specimen at the laboratory. Scales were used for age determination. Sex determination and fecundity were determined. Population dynamic parameters as well as stock assessment including cohort analysis were estimated using FISAT software. The finding showed that the mean of fork length and body weight of the Caspian Vimba were 168.4±2.6 mm and 71.94±32.24 g respectively. Strong correlation was found between these two variables (a= 0.012; b = 3.047; r2 = 0.955). 92 specimens were studied from the fecundity point of view. This species was found to have more abundance in spring (esp. Apr-May). The samples composed of 397(42.6%) male, 537(57.4%) female; Overall sex ratio (M: F =1: 1.35) was significantly different from the expected 1:1 ratio (p ≤0.05). The advanced stages of maturity (4th & 5th) were found in April and May. The highest Gonadosomatic Index in female was in May and the lowest one was in July. This fish is therefore a spring spawner. The maximum absolute and relative fecundities were 34640 and 260.9, respectively; the minimum absolute and relative fecundities were 5400 and 94.5 respectively. The averages of absolute and relative fecundities were 17198±7710 and 171.85±48.8, respectively. Coefficient vacuity index was 59.2% which indicates that this fish is mesophagous. Among of living creature consumes by Caspian Vimba mollusks, 76 arthropods, worms, plants, detritus and fishes were found 32.9% , 26.7% , 13.4% , 17% , 4.4% and 1.6% respectively. The infinite fork lengths were 261 mm for females, 25mm for males and 261 mm for both sexes respectively. For population growth and mortality parameters; K ( 0.28 per year for both sexes, 0.3 per year for males, 0.33 per year for females); t0 ( -0.65 year for both sexes, -0.23 year in females, -0.51 year in males ); Φ' ( 2.28 ); Z ( 0.98 per year ); M ( 0.59 per year); F ( 0.39 per year) and Exploitation coefficient was 0.4. The analysis showed that total biomass and MSY were 1336 and 528.8 tonnes respectively.

Population dynamics and stock assessment of the common carp (Cyprinus carpio) in Iranian waters of the Caspian Sea

In order to come up with the responsible fishing pattern of common carp, there was a need to identify some of the biological characteristics and stock assessment of carp in Iranian waters of the Caspian Sea .The fork length ,weight ,age ,growth parameters of von bertalanffy and mortality rates of common carp were estimated from oct 2006 to sept 2007.Based on the exponential relationship between length and weight in the size range 6.3-65.6 cm ,b was calculated 2.895, 2.843 and 2.925 respectively for combined sexes ,males and females. The mean condition factor was 1.9 which is close to the ideal condition.The results from measuring 3170 specimens ,were showed the first fork length of maturity was 30 cm for males and 32 cm for females. The results indicated that females were predominate and sex ratio was 0.66:1 (M:F) and chi-squares analysis showeda significant difference between males and females.(p<0.05).Length infinity and growth coefficient were calculated by three different methods as below: Length frequency analysis : k=0.17 L∞ =68.04 Age-Length Key k=0.15 L∞ =74.25 Back calculation : k=0.14 L∞ =68.4 The mortality parameters and exploitation rate were estimated as below : Z=0.73 per year M=0.31 per year F=0.42 per year E=0.56 Refer to amount of common carp catch in 2007 -08 ,biomass was calculated 9640.2 tones by jone's cohort analysis and MSY 2374.5 tones.According to analysis ,the number of common carp in the distribution area (Iranian part of the Caspian Sea ) was estimated 24 millions in the 2006-07.

Indian squid, Uroteuthis duvauceli, is an important commercial marine fauna in the coastal waters of Oman Sea

About 3600 specimens were collected by bottom trawl at 15 sampling stations. 24 biometric characters were measured for each specimens at the laboratory.. Microscopic cross – sections of statolith were used for age determination. Sex determination and fecundity were determined. Population dynamics parameters as well as stock as stock assessment including cohort analysis were estimated using FISAT software. The findings showed that Dorsal Mantle Length (DML) and Body weight (BW) of the Indian squid were 133.9 ± 0.78 mm and 99.61 ± 0.95 g respectively. Strong correlation was found between these 2 variables (R2 = 0.90). The maximum age was 5 years. Relationship between DML and age was highly significantly of p ≤ 0.05. Overall sex ratio (M: F = 0.52) was significantly different from the expected 1:1 ratio (p ≤ 0.05). The ovary weight and nidamental glands weight were 7.72 ± 0.0006 g and 3.07 ± 0.0003g respectively. Absolute and relative fecundity of the Indian squid were found to be 122733 ± 30.87 and 2348 ± 0.4 respectively. GSI were 14.35 in April and 8.63 in July. This squid is therefore a spring spawner. The infinite dorsal mantle length were 258.62 mm for females, 194.72 mm for males and 252.02 for both sexes respectively. For population growth and mortality parameters; K (0.65 per year for both sexes, 0.85 per year for males, 0.65 per year for females); t0 (0.24year for both sexes, 0.22 year in females, 0.26 year in male); φ` (2.30 in both sexes, 2.47 for males, 2.37 for females); Z (1.17 per year for both sexes, 1.10 per year in females, 1.39 per year, in males); M (0.70 per year for both sexes, 0.90 for males, 0.67 for females); F(0.27 per year for both sexes, 0.27 per year in males, 0.195 per year in females). Exploitation coefficient were 0.51 per year for both sexes, 0.57 per year males and 0.51 per year females respectively. The results indicates that since the Indian squid is a short live aquatic organism, therefore, the exploitation coefficient could be raised to 0.7 per year. The analysis showed that total biomass and MSY were 10103.5 ton and 2576.4 ton respectively. These findings are the first study of its sort about the Indian squid in the coastal waters of Oman Sea as well as North-West of Indian Ocean.

社会发展与中国人人格变迁——控制测验理论与工具的变异后不同时期的中国人人格差异研究

In non-western society，researches on social development and personality change focused on economic development and social modernization. The present study is aimed at exploring the relationship between the social transformation and personality changes of Chinese people by using so-called indigenous personality measurement of CPAI (Chinese Personality Assessment Inventory). Meanwhile, the influence of CPAI measurement itself and measurement theory were also taken into consideration. In study 1, two sets of CPAI data collected in a 10 year interval were analyzed. At the same time, the CPAI-2 data was analyzed in terms of modernization level of various cities from which the data were collected. However, this study didn’t consider the importance of “equivalence” of the measurement, CPAI. In study 2, we detected DIF (Differential item functioning) across the different period groups to confirm if CPAI was equal to people in different period. In this process, both CTT and IRT method were used. The outcome reminded us that there were some DIF items. In study 3, to make sure that the personality measurement is fair to people in different period, we only saved those items whose DIF effect size lower than 0.01, and used IRT method to estimate test-taker’s personality. Then, cohort analysis was used to explore the pattern of personality change of Chinese people. In study 4, we factor-analyzed the DIF items to find the relation between social transformation and the latent personality variable which were composed of DIF items. From these 4 studies, we could got the following conclusions: (1) The CPAI 22 traits could be divided into two categories, with the changing of age, period and cohort, type I traits didn’t change, they were Logical vs Affective Orientation, Enterprise, Responsibility, Inferiority vs Self-Acceptance, Optimism vs Pessimism, Face, Family, Defensive, Graciousness vs Meanness; While with the changing of age, period and cohort, type II traits changed, they were Leadership, Self vs. Social Orientation, Veraciousness vs Slickness, Traditionalism vs Modernity, Harmony, Renqing, Meticulousness, Extraversion vs Introversion, Emotionality, Practical Mindedness, Internal vs External Locus of Control, Thrift vs Extravagance, Discipline. Meanwhile DIF items measured 5 psychologycial characteristics which changed greatly with the changing of age, period and cohort, they were Life attitude of Cynicism-realism, Psychological maladjustment, Coping style of Waiyuanneifang, Self-efficacy, the value of Individualism. (2) In sum, Chinese people in 1992 were more traditional than those in 2001, and with the 10-year of rapid development, according to the market economy’s needs, Chinese people became more individualism. (3) The DIF method of CTT and IRT were comparable. But, in generally, IRT method was more accurate and valid in detecting DIF as were as estimating personality. (4) The DIF outcomes showed that CPAI had good item validity. Meanwhile, it’s possible to develop a subscale by using CPAI items to assess some psychological characteristics. In this current study, according to their stability and variability, we could divided personality traits and psychological characteristics into 3 categories, and the outcome supported the hypothesis of “Six Factor Model”, these foundings were of some theoretic meanings. Meanwhile, as the relation between social development and personality change being explored, it certain help Chinese people cope with the rapid changing society. In this study, we also found that it’s possible to develop a subscale by using CPAI items to assess obverse personality traits and it had some practical use. Furthermore, the use of different measurement theory and cohort analysis embodied some innovation in methodology.

Fishery Exploitation and Stock Assessment of the Endangered Nassau Grouper, Epinephelus Striatus (Actinopterygii: Perciformes: Serranidae), in the Turks and Caicos Islands

The Nassau grouper, Epinephelus striatus (Bloch, 1792), is an endangered species that has been historically overexploited in numerous fisheries throughout its range in the Caribbean and tropical West Atlantic. Data relating fishery exploitation levels to stock abundance of the species are deficient, and protective regulations for the Nassau grouper are yet to be implemented in the Turks and Caicos Islands (TCI). The goal of this study was to conduct a stock assessment and evaluate the exploitation status of the Nassau grouper in the TCI. Materials and methods. Calibrated length cohort analysis was applied to published fisheries data on Nassau grouper landings in the TCI. The total lengths of Nassau groupers among the catches of spearfishers, lobster trappers, and deep sea fishers on the island of South Caicos during 2006 and 2008 were used with estimates of growth, natural mortality, and total annual landings to derive exploitation benchmarks. Results. The TCI stock experienced low to moderate fishing mortality (0.28, 0.18) and exploitation rates (0.49, 0.38) during the period of the study (2006, 2008). However, 21.2%-64.4% of all landings were reproductively immature. Spearfishing appeared to contribute most to fishing mortality relative to the use of lobster traps or hydraulic reels along bank drop-offs. Conclusion. In comparison with available fisheries data for the wider Caribbean, the results reveal the TCI as one of the remaining sites, in addition to the Bahamas, with a substantial Nassau grouper stock. In light of increasing development and tourism in the TCI, continued monitoring is essential to maintain sustainable harvesting practices.

Oesophageal cancer survival in Europe:A EUROCARE-4 study

Oesophageal cancer survival is poor with variation across Europe. No pan-European studies of survival differences by oesophageal cancer subtype exist. This study investigates rates and trends in oesophageal cancer survival across Europe. Data for primary malignant oesophageal cancer diagnosed in 1995-1999 and followed up to the end of 2003 was obtained from 66 cancer registries in 24 European countries. Relative survival was calculated using the Hakulinen approach. Staging data were available from 19 registries. Survival by region, gender, age, morphology and stage was investigated. Cohort analysis and the period approach were applied to investigate survival trends from 1988 to 2002 for 31 registries in 17 countries. In total 51,499 cases of oesophageal cancer diagnosed 1995-1999 were analysed. Overall, European 1- and 5-year survival rates were 33.4% (95% CI 32.9-33.9%) and 9.8% (95% CI 9.4-10.1%), respectively. Males, older patients and patients with late stage disease had poorer 1- and 5-year relative survival. Patients with squamous cell carcinoma had poorer 1-year relative survival. Regional variation in survival was observed with Central Europe above and Eastern Europe below the European pool. Survival for distant stage disease was similar across Europe while survival rates for localised disease were below the European pool in Eastern and Southern Europe. Improvement in European 1-year relative survival was reported (p=0.016). Oesophageal cancer survival was poor across Europe. Persistent regional variations in 1-year survival point to a need for a high resolution study of diagnostic and treatment practices of oesophageal cancer.

Statin Use and Risk of Delirium in the Critically Ill

Rationale: Delirium is common in intensive care unit (ICU) patients and is a predictor of worse outcomes and neuroinflammation is a possible mechanism. The antiinflammatory actions of statins may reduce delirium.

Objectives: To determine whether critically ill patients receiving statin therapy had a reduced risk of delirium than those not on statins.

Methods: A prospective cohort analysis of data from consecutive ICU patients admitted to a UK mixed medical and surgical critical care unit between August 2011 and February 2012; the Confusion Assessment Method for ICU was used to determine the days each patient was assessed as being free of delirium during ICU admission.

Measurements and Main Results: Delirium-free days, daily administration of statins, and serum C-reactive protein (CRP) were recorded. Four hundred and seventy consecutive critical care patients were followed, of whom 151 patients received statins. Using randomeffects multivariable logistic regression, statin administration the previous evening was associated with the patient being assessed as free of delirium (odds ratio, 2.28; confidence interval, 1.01-5.13; P , 0.05) and with lower CRP (b = 20.52; P , 0.01) the following day. When the association between statin and being assessed as free of delirium was controlled for CRP, the effect size became nonsignificant (odds ratio, 1.56; confidence interval, 0.64-3.79; P = 0.32).

Conclusions: Ongoing statin therapy is associated with a lower daily risk of delirium in critically ill patients. An ongoing clinical trial, informed by this study, is investigating if statins are a potential therapy for delirium in the critically ill.Copyright © 2014 by the American Thoracic Society.

Evaluation and Potential Cost-Effectiveness of Active Surveillance Pharmacovigilance for First-Line HAART in Namibia

Thesis (Ph.D.)--University of Washington, 2016-02

Cambios en el régimen de pensiones en Colombia y su efecto en el margen intensivo de la oferta laboral

En Colombia, como en muchos países de América Latina, en los años 80 y 90 se hicieron cambios importantes en los regímenes de pensiones. Este trabajo hace un análisis de uno de esos cambios en Colombia. El cambio consistió en aumentar el tiempo de cotización necesario para reclamar los beneficios pensionales y la inclusión del salario dentro de la fórmula del monto de pensiones. Para este propósito se estudia el impacto sobre la oferta laboral de un cambio exógeno en estas condiciones usando un diseño de regresión discontinua. Se encuentra un efecto positivo sobre las horas promedio trabajadas en la semana.

Factores pronósticos en la agudeza visual final de pacientes con oclusión venosa retiniana tratados con terapia antiangiogénica

Objetivo: determinar los diferentes factores clínicos y de imagen pronósticos para la agudeza visual final a los 3, 6 y 12 meses en los pacientes con oclusiones venosas retinianas tratados con terapia antiangiogénica. Material y métodos: estudio longitudinal de una cohorte de 60 pacientes con oclusión venosa retiniana tratados con terapia antiangiogénica intravitrea con ranibizumab y bevacizumab tomados retrospectivamente entre 2010 y 2012. Posteriormente se realizó un estudio analítico de cohorte retrospectiva, para establecer la asociación y predicción de los cambios de la agudeza visual. Resultados: se encontró una diferencia estadísticamente significativa entre la línea base, 3, 6 y 12 meses post tratamiento. (p < 0.001, prueba de Friedman). En el modelo explicativo de los cambios de la agudeza visual a los 3, 6 y 12 meses con la línea base, se encontró asociación significativa la presencia de IS/OS a los 3 meses con los cambios de la agudeza visual a los 6 meses (r2=.232, p< 0.001) y a los 12 meses (r2=.506, p< 0.001), en este último también se encontró asociado el género masculino (r2=.277 p< 0.001). Tomando los valores de la agudeza visual a los 3,6 y 12 meses y como covariable la agudeza visual inicial se encontró asociación significativa en los tres momentos, 3 meses (r2=0.697, p< 0.001), 6 meses (r2=745, p< 0.001) y 12 meses y (r2=786, p< 0.001), se encontró asociación significativa el presentar oclusión venosa de rama comparada con oclusión central con los cambios de la agudeza visual a los 6 meses (r2=.662, p=0.04) Conclusión: la presencia de IS/OS a los 3 meses y la agudeza visual inicial tienen una alta capacidad predictora de la agudeza visual a los 6 y 12 meses, el género masculino tiene relación con mejoría de la agudeza visual final y la oclusión de rama tiene relación con la mejoría de la agudeza visual a 6 meses.

Evaluación de la mecánica ventricular izquierda mediante speckle tracking en pacientes sanos en la Clínica Shaio

Introducción: La ecocardiografía es actualmente la técnica de imagen diagnóstica más utilizada para la evaluación de la anatomía y la función cardiovascular. En la actualidad se está utilizando la ecocardiografía por speckle tracking la cual permite una evaluación mas objetiva y confiable de la función ventricular, sin embargo se requieren valores de referencia que hagan que los valores obtenidos sean válidos y útiles para determinar en forma mas oportuna conductas previas al deterioro de su función. Objetivo general: Determinar los valores de referencia para mecánica ventricular izquierda mediante ecocardiografía bidimensional por speckle tracking con equipo Toshiba Artida con transductor multifrecuencia de 3 megahertzios en pacientes sin patología cardiaca conocida en la Fundación Clínica Shaio en el año 2014. Metodología: Análisis de una cohorte prospectiva de todos los pacientes que ingresaron a la Fundación Clínica Shaio para evaluación ecocardiográfica sin patología cardiaca conocida entre los meses Agosto y Diciembre del 2014. Resultados: Se presenta este estudio de la evaluación de la mecánica ventricular izquierda en adultos sanos, los resultados son similares a los obtenidos en estudios de referencia, sin embargo se consideran de gran importancia ya que de acuerdo a la guía actual de evaluación de la mecánica ventricular por strain rate es importante que cada equipo se encuentre estandarizado con el fin de tener resultados válidos de acuerdo a las diferentes patologías en las que se puede aplicar y a nuestra población.

Parametric pension reform and the intensive margin of labor supply, evidence from Colombia

We analyze the effect of a parametric reform of the fully-funded pension regime in Colombia on the intensive margin of the labor supply. We take advantage of a threshold defined by law in order to identify the causal effect using a regression discontinuity design. We find that a pension system that increases retirement age and the minimum weeks during which workers must contribute to claim pension benefits causes an increase of around 2 hours on the number of weekly worked hours; this corresponds to 4% of the average number of weekly worked hours or around 14% of a standard deviation of weekly worked hours. The effect is robust to different specifications, polynomial orders and sample sizes.