Population dynamics of Turbo militaris (Gastropoda: Turbinidae) on rocky shores in a subtropical marine park: implications for management

Understanding the relative impacts of harvesting across an area such as a marine park is vital if the goals of fisheries management are to be met. Given their accessibility, densities of targeted intertidal turbinids should be relatively simple to quantify; however, natural spatial and temporal variability in these populations has hampered this effort. This study aimed to quantify short-term population dynamics of Turbo militaris in relation to current zoning regulations and accessibility. While our results reflected the variability found by other studies, we also detected significantly lower densities at a headland where harvesting is known to occur, and found a trend towards denser aggregations at more remote locations. Importantly, we found that densities at some locations were so low that current fisheries bag limits may be ineffective for protecting populations at local scales. Comparisons between study sites suggest a combination of no-take zoning and inaccessibility may provide the most effective protection for this species. However, a greater understanding of the wider impacts of harvesting, and processes affecting recovery, are essential to ensure sustainable management of this fishery.     

Reducing human impacts on central Californian intertidal gastropods: are marine protected areas effective?

The central California coast is visited by millions of people every year, many of whom collect intertidal gastropods for food, bait or recreation in near-shore marine environments. The harvesting of these animals has caused a decline in body size because humans preferentially take the largest individuals. Marine protected areas (MPAs) may serve to protect gastropods from this impact. The average body size and frequency of four gastropod species from eight study locations along the central California coast were determined. Five study locations were in MPAs and three study locations were in non-MPA zones. Gastropods in four California museums were measured and compared to specimens collected in the field. Three of the four species studied were larger and/or more frequent in MPAs than outside MPAs, including both harvested species and one unharvested species. For three of the four species, the average size of individuals from MPA sites was significantly smaller than museum specimens, but this may be due, in part, to our sampling procedure. These findings indicate that MPAs can be effective at reducing human impacts for some species, but that further study is needed to make MPAs as effective as possible for more species.     

Control of antibody high and low molecular weight species by depth filtration-based cell culture harvesting

Depth filtration-based harvesting is widely used in mAb manufacturing to remove cell and process-related impurities. However, it has not been studied on control of product-related impurities, which are very critical for product quality. In this article, we studied the interactions of depth filter with high and low molecular weight species (HMWs and LMWs) for their direct removal from cell culture. The process parameters (filter, loading, temperature, and flux) were evaluated for adsorption of HMWs and LMWs by depth filters. The adsorption is significantly dependent on filter media and loading capacity and is mainly on the basis of hydrophobic interaction during harvesting. The HMW and LMW species were characterized as HMW1, HMW2, LMW1, and LMW2. The increasing binding from LMW2 to LMW1, HMW1, and HMW2 is correlated with their increasing hydrophobicity score. Adsorption using enriched HMW sample demonstrated similar total protein binding capacity (36–40 g/m²) between depth filters D0HC and X0HC. However, X0HC has stronger HMW binding than D0HC (71% vs 43% of bound protein), indicating more hydrophobic interaction in X0HC. HMW2 DBC on X0HC reached 12 g/m², similar to protein binding on hydrophobic interaction membrane adsorbers. Further study showed LMW can induce HMW formation. This study provides a critical understanding of HMW and LMW interaction with depth filters. The strategy of HMW and LMW control by depth filtration-based harvesting was implemented successfully in mAb manufacturing.     

Plant Growth Regulators in Citriculture: World Current Uses

Plant growth regulators (PGRs), both naturally occurring and synthetic, are used extensively in citriculture not only to help growers solve production problems, but also to increase the market value of the crop and to improve grower returns. Yield increases are obtained via an improvement in fruit set, particularly for shybearing cultivars, and/or fruit size, especially for the “small-fruit” group of mandarins. Increased fruit number per tree is achieved indirectly through an increase in flower number as a result of better flower initiation or by a direct effect on fruit set. Improved fruit size is brought about directly by stimulating the growth of fruit tissues or indirectly by reducing fruit number by partial inhibition of flower initiation or by subsequent fruit removal. PGRs are also used to hasten maturity, to delay harvest, and to maintain fruit quality postharvest, resulting in greater profits to the grower. This article provides an overview of current uses of PGRs in citriculture. The reported information is based on an international survey and a review of recent technical and scientific literature published on the subject. Procedures and techniques used to enhance the efficacy of PGRs, including surfactants and compatibility considerations, are presented and discussed. The detailed information presented in the text is summarized in tables designed to provide a convenient reference for researchers and growers alike. Included in the tables are the names of the individuals who were the source of the information. A comprehensive list of these individuals and their addresses follows the tables. Whereas the results of the survey indicate extensive uses of PGRs in citriculture, the authors admit that the survey is incomplete and extend their apologies to researchers in countries not represented in the review and for inadvertent omissions.