Report of the Study Group on “ Fisheries and Ecosystem Response to Recent Regime Shifts”

EXECUTIVE SUMMARY 1. DECADAL-SCALE CLIMATE EVENTS 1.1 Introduction 1.2 Basin-scale Patterns 1.3 Long Time Series in the North Pacific 1.4 Decadal Climate Variability in Ecological Regions of the North Pacific 1.5 Mechanisms 1.6 References 2. COHERENT REGIONAL RESPONSES 2.1 Introduction 2.2 Central North Pacific (CNP) 2.3 California Current System (CCS) 2.4 Gulf of Alaska (GOA) 2.5 Bering Sea and Aleutian Islands 2.6 Western North Pacific (WNP) 2.7 Coherence in Regional Responses to the 1998 Regime Shift 2.8 Climate Indicators for Detecting Regime Shifts 2.9 References 3. IMPLICATIONS FOR THE MANAGEMENT OF MARINE RESOURCES 3.1 Introduction 3.2 Response Time of Biota to Regime Shifts 3.3 Response Time of Management to Regime Shifts 3.4 Provision of Stock Assessment Advice 3.5 Decision Rules 3.6 References 4. SUGGESTED LITERATURE 4.1 Climate Regimes 4.2 Impacts on Lower Trophic Levels 4.3 Impacts on Fish and Higher Trophic Levels 4.4 Impacts on Ecosystems and Possible Mechanisms 4.5 Regimes and Fisheries Management APPENDIX 1: RECENT ECOSYSTEM CHANGES IN THE CENTRAL NORTH PACIFIC A1.1 Introduction A1.2 Physical Oceanography A1.3 Lower Trophic Levels A1.4 Invertebrates A1.5 Fishes A1.6 References APPENDIX 2: RECENT ECOSYSTEM CHANGES IN THE CALIFORNIA CURRENT SYSTEM A2.1 Introduction A2.2 Physical Oceanography A2.3 Lower Trophic Levels A2.4 Invertebrates A2.5 Fishes A2.6 References APPENDIX 3: RECENT ECOSYSTEM CHANGES IN THE GULF OF ALASKA A3.1 Introduction A3.2 Physical Oceanography A3.3 Lower Trophic Levels A3.4 Invertebrates A3.5 Fishes A3.6 Higher Trophic Levels A3.7 Coherence in Gulf of Alaska Fish A3.8 Combined Standardized Indices of Recruitment and Survival Rate A3.9 References APPENDIX 4: RECENT ECOSYSTEM CHANGES IN THE BERING SEA AND ALEUTIAN ISLANDS A4.1 Introduction A4.2 Bering Sea Environmental Variables and Physical Oceanography A4.3 Bering Sea Lower Trophic Levels A4.4 Bering Sea Invertebrates A4.5 Bering Sea Fishes A4.6 Bering Sea Higher Trophic Levels A4.7 Coherence in Bering Sea Fish Responses A4.8 Combined Standardized Indices of Bering Fish Recruitment and Survival Rate A4.9 Aleutian Islands A4.10 References APPENDIX 5: RECENT ECOSYSTEM CHANGES IN THE WESTERN NORTH PACIFIC A5.1 Introduction A5.2 Sea of Okhotsk A5.3 Tsushima Current Region and Kuroshio/Oyashio Current Region A5.4 Bohai Sea, Yellow Sea, and East China Sea A5.5 References (168 page document)

The influence of disparate levels of submersed aquatic vegetation on largemouth bass population characteristics in a Georgia reservoir

Population characteristics of largemouth bass (Micropterous salmoides L.) including growth, body condition (relative weight), size structure, survival, and fecundity were examined in relation to abundance of submersed aquatic vegetation (SAV) coverage (primarily hydrilla Hydrilla verticillata L.f. Royle) in three major embayments of Lake Seminole, Georgia. Relative weight, fecundity, and growth of large-mouth bass in the Spring Creek embayment (76% areal SAV coverage) was considerably less than measured in the Chattahoochee and Flint river arms that contained lower SAV coverages (26% and 32%). It took fish 1.8 years longer to reach 406 mm in Spring Creek compared to the Chattahoochee-Flint arms. Consequently, fish were smaller in Spring Creek than in the Chattahoochee-Flint arms. In addition, due to slower growth rates and lower fecundity-to-body weight relation, we predicted a 47% reduction in total potential ova production in Spring Creek compared to the other two reservoir embayments. The annual survival rate of 3 to 10 year old largemouth bass was higher in Spring Creek (84%) than in the Chattahoochee-Flint arms (72%) and suggested either lower harvest and/or lower accessibility of particularly larger fish to angling in dense vegetation. Contrary to our expectaions, the fit between number-at-age and age in a catch-curve regression was weaker for fish collected in Spring Creek and suggested greater recruitment variability has occurred over time in this highly vegetated embayment. In Lake Seminole, spatial differences in largemouth bass population characterstics were associated with disparate levels of SAV. Our data suggest that a reduction in hydrilla, but maintenance of an intermediate level of SAV in Spring Creek, should improve largermouth bass population in this arm of the reservoir.

Interpreting spotted dolphin age distributions

Previous work has determined the age distribution from a sample of spotted dolphins (Stenella attenuata) killed in the eastern Pacific tuna purse-seine fishery. In this paper we examine the usefulness of this age distribution for estimating natural mortality rates. The observed age distribution has a deficiency of individuals from 5-15 years and cannot represent a stable age distribution. Sampling bias and errors in age interpretation are examined as possible causes of the "dip" in the observed age structure. Natural mortality rates are estimated for the 15+ age classes based on the assumption that these are sampled representatively. The resulting annual survival rate rates. (PDF contains 30 pages.)

Population dynamics of the anchoveta, Cetengraulis mysticetus, in the Gulf of Panama, as determined by tagging experiments

ENGLISH: The anchoveta is the major constituent of the important bait and reduction fisheries of the Gulf of Panama. It is a short-lived species, the great majority of the catch consisting of fish in their first year of life. Fish for reduction are caught chiefly in the Isla Verde area, between Punta Chame and the entrance of the Panama Canal. In 1960 and 1961 anchovetas were tagged with metal internal tags and released in the major areas of occurrence of this species. The tags were recovered from the meal in the reduction plants with magnets. From the 53,380 fish tagged in 1960, 745 tags were returned during the 1960 season, 246 during the 1961 season, and 8 during the 1962 season. From the 113,202 tagged in 1961, 373 tags were returned during the 1961 season and 48 during the 1962 season. Complete catch statistics are available, and length-frequency and length-weight data were used to convert these from pounds to numbers of fish of each year class. The annual survival rate for the fish of the 1959 year class in the Isla Verde area was estimated to be 0.086 by the Chapman-Robson method, 0.102 by the year-class method, and 0.088 by the Jackson positive method. The first method is considered to give the best estimate. Six estimates of the population of fish of the 1959 year class in the Isla Verde area were obtained from the sample tag ratios of six experiments conducted in that area in 1960. The estimates differed due to the temporal decrease in the population, but the downward trend corresponded fairly well to what was expected from the total annual mortality rate. It was estimated that the population of 1959-year class fish was about 818 million on March 8, 1960, and about 70 million on March 8, 1961. As the population of anchovetas decreases during the season the effort increases sufficiently that the catch remains roughly constant. This is described as the "constant absolute catch" type fishery. Of the original population of fish in the Isla Verde area at the beginning of the 1960 season, about 11 per cent were caught and 81 per cent died of natural causes. Evaluation of growth and mortality data demonstrated that beginning the fishery for the youngest age group later than March 8 (the date it began in 1960) would reduce the yield per recruit, while increasing the fishing effort would greatly increase it. Further, it is believed unlikely that increases in the catch in the Isla Verde area alone would noticeably decrease the number of recruits to that area. Therefore there is no foreseeable need for regulation of the fishery. SPANISH: El principal constituyente de la importante pesquería para carnada y para reducción en el Golfo de Panamá es la anchoveta. Es una especie de vida corta cuya pesca, en su mayor parte, está constituida por peces que se encuentran en su primer año de vida. Para la industria de reducción los peces son capturados principalmente en el área de Isla Verde, entre Punta Chame y la entrada del Canal de Panamá. En 1960 y 1961 las anchovetas fueron marcadas con marcas metálicas internas y liberadas en las áreas más importantes en que se encuentra esta especie. Las marcas fueron recobradas de la harina en las plantas de reducción por medio de magnetos. De los 53,380 peces marcados en 1960, fueron devueltas 745 marcas durante la temporada pesquera de 1960, 246 durante la de 1961, y 8 durante la de 1962. De los 113,202 marcados en 1961, 373 marcas fueron devueltas durante la temporada pesquera de 1961 y 48 durante la de 1962. Se dispone de estadísticas completas de captura, y los datos de frecuencia-longitud y de longitud-peso fueron usados para convertir éstos de libras a números de peces de cada clase anual. La tasa anual de supervivencia correspondiente a la clase anual de 1959 en el área de Isla Verde estimó en 0.086 por medio del método Chapman-Robson; en 0.102 por método de la clase anual; y en 0.088 por el método positivo de Jackson. Se considera que el primer método dé la mejor estimación. Seis estimaciones de la población de peces de la clase anual 1959 en el área de Isla Verde fueron obtenidas según la proporción de marcas halladas en las muestras correspondientes a seis experimentos efectuados en aquella área en 1960. Las estimaciones variaron debido a la disminución temporal de la población, pero esta tendencia descendente correspondió bastante bien a lo que se esperaba según la tasa total de mortalidad anual. Se estimó que la población de peces de la clase anual de 1959 era de unos 818 millones el 8 de marzo de 1960, y aproximadamente de unos 70 millones el 8 de marzo de 1961. Conforme a que la población de anchovetas disminuye durante la temporada pesquera, el esfuerzo aumenta lo suficientemente como para que la pesca se mantenga más o menos constante. Este es el tipo de pesquería descrito como de "captura absoluta constante". De la población original de peces en el área de Isla Verde al comienzo de la temporada pesquera de 1960, cerca del 11 por ciento fue capturada y el 81 por ciento murió por causas naturales. La evaluación de los datos del crecimiento mortalidad demostraron que al comenzar la pesquería a explotar grupo de edad más joven en una fecha posterior al 8 de marzo (la fecha en que comenzó en 1960) se reduciría el rendimiento por recluta, mientras que al aumentar el esfuerzo de pesca lo aumentaría considerablemente. Más aún, se cree improbable que el aumento en la pesca en el área de Isla Verde de por sí disminuyera perceptiblemente el número de reclutas en esa área. En consecuencia no se prevé la necesidad de una reglamentación de la pesquería. (PDF contains 172 pages.)

Deutsche und internationale Dorschfischerei in der Ostsee im Jahr 1998

In 1998 the longtime series of the standardized bottom trawl surveys conducted in the western Baltic (ICES Sub-division (SD) 22 and 24 since 1978) during spring and autumn and also in the eastern Baltic (ICES Sub-division since 1993) during spring were continued. The results of the surveys as well as those of a sampling programme carried out on board of commercial cutters (mainly financed by an EU study project) and on the market, the investigation of the survival rate of the discards, and the landing statistics are the basis of the analysis of the German and international cod fishery in 1998. The German cod fishery was concentrated on the ICES SD 22 and 24 (total landings 9722 t). The total landings from the fishing grounds east off Bornholm, the traditional German fishing ground, amounted only to about 1270 t. The German cod quota was utilized at 64 %. The fishery in the ICES SD 22 and 24 was characterized by a discard rate of undersized cod of 13 %. That corresponds to about 7.3 million specimens of 0-group, one- and two-years-old youngfish, respectively. The total international cod landings of the Baltic amounted to 101 500 t. In comparison with 1997 (total landings 129 600 t) the landing decreased by 23 %. The percentage utilization of the cod TAC (1998: 140 000 t) amounted to 74 % in 1998.

Investment prospects in the production of the common carp (Cyprinus carpio) fingerlings in freshwater ponds

Since the introduction of Common carp Cyprinus carpio in Oyo State (Nigeria) from Israel in 1964, various local breeding methods have been employed in carp rearing to improve the survival rate at all stages of development during breeding. The physico-chemical parameters of the ponds which were simultaneously investigated for carp rearing in this study includes temperature (t), dissolved oxygen (DO) and hydrogen-ion concentration (pH). However, high rates of water displacement in the breeding ponds were unfavourable to the development of zooplankton which play important role in the food web of C. carpio. The survival rates of 15.88-69.50% and 19.60-33.83% obtained for the egg-hatchling and hatchling-fingerling stages respectively were encouraging. A breeding performance of this magnitude was found to be viable, breaking even in the fourth year. However, an increase in size of this trial project would be more profitable and increase fingerling supply as well as provide employment opportunities. This study thereby provides some baseline information on some local techniques and progress in the propagation of C. carpio and scope for further improvement

Suitability of calorie fortified diets for improving the production of Clarias gariepinus broodstock and fry

The findings are presented of an experiment conducted to determine the adequate level of calorie in diets that is necessary to bring Clarias gariepinus female broodstock to grand stage. The effect of different calorie level on the quality and quantity of egg produced by C. gariepinus broodstock and the survival rate of the fry fed the same diets and those fed harvested zooplankton were also investigated

Preliminary studies on the effects of light duration on the growth and performance of Clarias gariepinus fingerlings

The effects of light duration on the growth and performance of Clarias gariepinus fingerlings were investigated using artificial methods to simulate continuous day length and absolute darkness. The normal day length (12-H Light and 12-H Darkness) served as the control. Among some of the factors affected by the varying photoperiods there were body coloration, feeding efficiency, survival rate and Specific Growth Rate (SGR). There was notably no significant difference between the SGR of the 0-photoperiod culture and the control (P>0.05) but there was significant difference between the 0-photoperiod and the 24-H photoperiod experiment (P<0.05). The haematological profile analysed showed various degrees of changes in the blood parameters of fish cultured under different photoperiods. These changes however, did not show significant differences when subjected to statistical analysis

Growth response of Clarias gariepinus fry to organic and inorganic fertilizers

The growth response of Clarias gariepinus was investigated in various types of fertilizers. Fertilizer type was found to influence plankton abundance which in turn determine the growth and well being of C. gariepinus. The best weight increase recorded was in cow dung /NPK (1.37~c1.01g) followed by poultry (0.49~c0.31g), NPK/poultry (0.05~c0.25g) and NPK(0.03~c0.57g) The survival rate in these treatments were cow dung/NPK (100%), poultry (100%), NPK/cow/poultry (33%) and NPK (8%)

Growth performance of exotic Oreochromis niloticus, exotic Oreochromis niloticus fed with pelleted feeds in flow-through system

Local, exotic and hybrid tilapia fingerlings were fed 45% crude protein diet containing 18% fish meal in a flow through system in triplicate and their growth and food utilization observed for 14 weeks. At the end of the study, the hybrid (Exotic Oreochromis niloticus male x Exotic Oreochromis aureus female) fingerlings had higher growth rate and food conversion ratio (FCR) than the other treatments. This was followed by Exotic Oreochromis niloticus fingerlings. The exotic Oreochromis niloticus fingerlings came next while the local Oreochromis niloticus fingerlings were the least in growth performance. The survival rate of the local O. niloticus was however higher than the other treatments

Growth performance of Heteroclarias fed maggot meal at varying inclusion levels

70-day growth trial was conducted with Heteroclarias: Heterobranchus bidorsalis X Clarias gariepinus (mean weight 0.64~c0.006g) fed diets based on various inclusion levels of Maggot Meal. The fishmeal in the control diet was replaced with maggot meals at 25%, 50%, 75% and 100% levels to supply 40% crude protein in the final diets. The trails were conducted in glass tanks (60cmx30cmx30cm). Evaluation of growth parameters and nutrient utilization of the fish was based on weight gains, protein intake, protein efficiency ratio, net protein utilization, feed conversion efficiency and carcass analysis. Best growth and feed conversion efficiency were obtained with the 75% dietary inclusion of maggot meal. There was no significant differences (P>0.055) between the group of fish on 50% and 75% dietary inclusion maggot meal in growth performance and protein efficiency ratio but, there was a significant (P<0.05) difference in the NPU (Net Protein Utilization) and protein gain between the control diet and those fed on maggot meals. There was no marked variation in the survival rate of fish on all diets

Determination of optimum stocking density of Macrobrachium rosenbergii larvae using multiple feed in a commercial hatchery at Cox’s Bazar, Bangladesh

Experimental stocking density of Macrobrachium rosenbergii in larval rearing was conducted in A.G. Aqua Hatchery, Chakaria, Bangladesh to study the effect of different stocking densities on growth, survival rate and diseases stress under hatchery condition. The research work was conducted using six cemented rectangular tanks having 3m3 capacity (1.5mX2mX1m) each. Stocking density were maintained in three experimental setup as 200, 150 and 100ind/L of the T1, T2 and T3 respectively with one replicate each. The larvae were fed with Artemia nauplii, Custard, Maxima and brine shrimp flakes. Water quality was maintained by exchanging 20-30% (12ppt saline water) daily. During the study period, temperature, pH, DO, salinity, nitrite-nitrogen, ammonia and alkalinity were maintained from 28.5-31.5ºC, 7.5-7.8, 5.8-5.9mg/L, 12-13ppt, 0.14-0.2 mg/L, 0.22-0.3mg/L, and 140-160mg/L respectively. The growth rates of larvae at 11th stage were recorded in terms of body length 0.115, 0.136, and 0.169 mm/day whereas body weight were observed 0.000115, 0.000180, and 0.000240g/day. The survival rate of larvae were found 21.8%, 30.4% and 51.3% in treatments T1, T2 and T3 respectively. PL was obtained as 43, 45, and 51PL/L and days required of 41, 38 and 34 days in stocking density of 200, 150, and 100ind/L respectively. It was found that the minimum of 34 days was required to attain the PL (12th stage) using the stocking density of 100 individuals/L. Cannibalism, Zoothamnium, Exuvia Entrapment Disease (EED), and Bacterial Necrosis (BN) were found to be the threat to the commercial hatchery operation that might responsible for potential larval damages which can be reduced by lowering the stocking densities in larval rearing tank that also increased the survival and growth rate.

Estudo aleatório e controlado do uso clínico de um primer autocondicionante na colagem de bráquetes ortodônticos

O uso de primers autocondicionantes tem sido proposto como uma alternativa para a redução de passos clínicos. O objetivo deste estudo clínico aleatório e controlado foi avaliar a performance de um sistema autocondicionante (Transbond Plus Self-Etching Primer, 3M Unitek - SEP) comparado a um sistema multipasso convencional (Transbond XT, 3M Unitek - TBXT) de colagem ortodôntica, durante um período de 12 meses. Vinte e oito pacientes participaram deste estudo, sendo estes alocados aos grupos SEP ou TBXT de forma aleatória, através de randomização em bloco. Um total de 548 bráquetes metálicos (Micro-Arch, prescrição Alexander, GAC International, Bohemia, NY) foram colados com uso da pasta adesiva Transbond XT (3M Unitek), sendo todos os produtos manuseados de acordo com as recomendações dos fabricantes. Foram totalizados 276 bráquetes no grupo controle e 272 no segundo. Curvas de sobrevivência Kaplan-Meier e o teste log-rank (p<0,05) foram utilizados para comparar o percentual de falhas adesivas para as duas técnicas. Ao final do período foram verificadas trinta e duas falhas adesivas (bráquetes descolados), sendo 19 (6,98%) falhas quando utilizado o primer autocondicionante (SEP) e 13 (4,71%) quando usado o primer convencional (TBXT). Não houve diferença significante entre a sobrevivência dos bráquetes entre os dois grupos avaliados (log-rank test, p=0,311). Quando a influência de gênero do paciente, arco dentário e tipo dentário (anterior ou posterior) foram analisados, somente o tipo dentário foi achado significante. Bráquetes de dentes posteriores apresentaram uma maior probabilidade de falha adesiva que os colados em dentes anteriores (p=0,013) Os autores concluem que o primer autocondicionante pode ser utilizado para colagem direta de bráquetes ortodônticos sem que sua sobrevivência clínica seja afetada.

Sobrevida em pacientes mulheres com câncer de pulmão em clínica especializada no Rio de Janeiro, 2000-2009

O câncer de pulmão é atualmente a neoplasia mais frequentemente diagnosticada, considerando ambos os sexos, e a principal causa de óbito por câncer em todo o mundo. A incidência e a mortalidade do câncer de pulmão vêm sendo influenciadas ao longo do tempo pela história do tabagismo e seus aspectos sócio-demográficos. Este estudo tem como objetivo analisar a sobrevida e fatores prognósticos em mulheres com câncer de pulmão assistidas em uma clínica especializada no Rio de Janeiro no período de 2000 a 2009. Foram analisadas 193 mulheres com diagnóstico de câncer de pulmão confirmado por exame histopatológico. Os dados foram obtidos diretamente do sistema informatizado de registros médicos do referido serviço. A idade do diagnóstico foi categorizada em quatro faixas etárias: até 49 anos, 50 a 59 anos, 60 a 69 anos e maior de 70anos. O tabagismo foi categorizado como não fumante, ex-fumante, fumante e fumante passiva. O estado nutricional foi avaliado pelo Índice de Massa Corpórea (IMC). A classificação histológica seguiu a divisão entre tumores de células não-pequenas (CPCNP) e tumores de pequenas células (CPCP). O estadiamento clínico se baseou na classificação do American Joint Committee on Cancer (AJCC) e Veterans Administration Lung Cancer Study Group (VALCSG) para os tumores de células não-pequenas e tumores de células pequenas, respectivamente. A modalidade de tratamento foi categorizada pela intenção da abordagem terapêutica em quatro grupos: controle, neoadjuvância, adjuvância e paliativa. Foram calculadas funções de sobrevida pelo método de Kaplan-Meier. Para os fatores prognósticos de risco, foram calculados os hazards ratios brutos e ajustados com intervalos de confiança de 95%, através do modelo de riscos proporcionais de Cox. A idade média das pacientes foi de 63 anos. Destas, 47,7% eram fumantes, 26,9% não fumantes, 19,7% ex-fumantes e 3,6% fumantes passivas. Em relação ao estado nutricional, 2,6% das pacientes apresentavam IMC baixo peso, 52,8% normal, 29,5% sobrepeso e 15% obesidade. A maioria dos casos, 169 (87,6%) pacientes, foi classificado como câncer de pulmão de células não-pequenas (CPCNP). Apenas 24 casos (12,4%) foram de câncer de pequenas células (CPCP). Durante o período estudado ocorreram 132 óbitos; 114 por CPCNP e 18 por CPCP. O tempo mediano de sobrevida para toda a coorte foi de 23,2 meses (IC95%: 16,9-33,5). Quando os dados foram estratificados por classificação tumoral, a sobrevida mediana nas pacientes com diagnóstico de CPCNP foi de 18,2 meses (IC95%: 15,6-25,5) e para aquelas com CPCP foi de 10,3 meses (IC95%: 8,4-19,3). A sobrevida encontrada em 24 meses foi de 49% (IC95%: 42,25-56,9), sendo 22,95 (IC95%: 0,6-49,3) para os tumores de pequenas células e 50,29% (IC95%: 43,1-58,7) para os tumores de células não- pequenas. Para o total das pacientes, as curvas de sobrevida estratificadas pelas variáveis selecionadas mostraram diferenças em relação à idade do diagnóstico (p=0,0023) nas faixas etárias intermediárias de 50-59 anos e 60-69 anos, se comparadas com os limites extremos (as mais idosas e as mais jovens). Não houve diferenças para o status de tabagismo (p=0,1484) nem para o IMC (p=0,6230). Na análise multivariada para todos os tumores, nenhum fator prognóstico influenciou no risco de morte. A idade nas categorias intermediárias (50-59 anos e 60-69 anos) e o IMC na categoria sobrepeso mostraram uma tendência à proteção, porém, não houve significância estatística. Para o grupo de mulheres com CPCNP, o modelo de riscos proporcionais apontou diferença em relação ao estadiamento clínico, especificamente o estádio IV (HR=3,36, IC95%: 1,66-6,8; p=0,001). As pacientes com idade entre 50-59 anos e sobrepeso mostraram uma tendência à diminuição do risco, embora sem significância estatística. Esses resultados mostram a necessidade de conhecer melhor o perfil das mulheres que desenvolvem câncer de pulmão e de realizar pesquisas que investiguem de forma mais aprofundada as condições que influenciam a evolução clínica dos casos e assim contribuir para o aprimoramento da abordagem terapêutica.

Efecto de la temperatura en el subproteoma de membrana externa de Escherichia coli

[es]En sus habitas naturales, los microorganismos están en un estado constante de adaptación a cambios tanto bióticos como abióticos. Ante situaciones de estré s, como por ejemplo cambios en nutriente s, temperatura o de osmolar idad , la s estrategias de supervivencia o adapta ción se puede n manifestar como cambios fenotípicos y genotípicos . En este estudio se analizaron algunos mecanismos de cambio asociados a la supervivencia y la composición proteica de membrana en Escherichia coli (bact eria mesófila), al ser expuesta a condiciones de ayuno y a temperaturas subó ptimas (4 y 20ºC). Al realizar un análisis comparativ o del subproteoma de membrana entre estas dos temperaturas, se observó que ante la ausencia de nutrientes, E. coli respondía de forma diferen te en la expresió n de proteí nas as ociadas a estructura (lipoproteínas), conservación de la energía y transporte, con un aumento en el nú mero de proteí nas expresadas a 20 o C. Se observó, además, una importante diferencia en la supervivencia a estas dos temperaturas, donde el número de células en el estado viable no cultivable (VNC) representaron un porcentaje importante a 20ºC