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Cu thin films and Cu2O microstructures were partially converted to the Metal‐Organic Frameworks (MOFs) Cu3(BTC)2 or Cu(TCPP) using an electrochemical process with a higher control and at milder conditions compared to the traditional solvothermal MOF synthesis. Initially, either a Cu thin film was sputtered, or different kinds of Cu or Cu2O microstructures were electrochemically deposited onto a conductive ITO glass substrate. Then, these Cu thin films or Cu‐based microstructures were subsequently coated with a thin layer of either Cu3(BTC)2 or Cu(TCPP) by controlled anodic dissolution of the Cu‐based substrate at room temperature and in the presence of the desired organic linker molecules: 1,3,5‐benzenetricarboxylic acid (BTC) or photoactive 4,4′,4′′,4′′′‐(Porphine‐5,10,15,20‐tetrayl) tetrakis(benzoic acid) (TCPP) in the electrolyte. An increase in size of the Cu micro cubes with exposed planes [100] of 38,7 % for the Cu2O@Cu3(BTC)2 and a 68,9 % increase for the Cu2O@Cu(TCPP) was roughly estimated. Finally, XRD, Raman spectroscopy and UV–vis absorption spectroscopy were used to characterize the initial Cu films or Cu‐based microstructures, and the obtained core‐shell Cu2O@Cu(BTC) and Cu2O@Cu(TCPP) microstructures. [ABSTRACT FROM AUTHOR]

Controlling the crystallization of Metal–Organic Frameworks (MOFs) at the nanoscale is currently challenging, and this hinders their utilization for multiple applications including photo(electro)chemistry and sensors. In this work, we show a synthetic protocol that enables the preparation of highly homogeneous Cu2O@MOF nanowires standing on a conductive support with extensive control over the crystallization of the MOF nanoparticles at the surface of the Cu2O nanowires. Cu2O nanowires were first prepared via templated electrodeposition, and then partially converted into the well-known Cu-MOF HKUST-1 by pulsed electrochemical oxidation. We show that the use of PVP as a capping agent during the electrochemical oxidation of Cu2O into HKUST-1 provides control over the growth of the MOF nanocrystals on the surface of the Cu2O nanowires, and that the size of the MOF crystals obtained can be tuned by changing the concentration of PVP dissolved in the electrolyte. In addition, we propose the use of benzoic acid as an alternative to achieve control over the size of the obtained MOF nanocrystals when the use of a capping agent should be avoided. [ABSTRACT FROM AUTHOR]

Two species of halfbeaks, ballyhoo, Hemiramphus brasiliensis, and balao, H. balao, form the basis of a relatively small but valuable bait fishery in southeastern Florida. Halfbeak landings increased rapidly in the late 1960's but are now relatively stable (about 450,000 kg or 1 million lb annually), and their ex-vessel price is about $600,000. Fishing methods, which had changed in the late 1960's when landings increased, have changed little since the 1970's. Data from a fishery-dependent survey (1988-91) show that catch rates were highest from October to February, when catches were dominated by large ballyhoo (>200 mm or 8 inches fork length (FL)); rates were lowest from May to September, when catches contained both species in more equal numbers and the size range was greater (about 150-250 mm FL) that it was for winter landings. There was little bycatch, and only flyingfishes (Exocoetidae) and needlefishes (Belonidae) occurred consistently. Comparisons of the 1988-91 data with similar data reported from 1974 indicated that halfbeak populations have remained relatively stable., Introduction In Florida, ballyhoo, Hemiramphus brasiliensis, and balao, H. balao, form the basis of an important bait fishery (Berkeley et al., 1975; Berkeley and Houde, 1978). They are harvested with [...]

Scaled herrings, Harengula jaguana (Clupeidae), inhabit nearshore (40-m isobath, rarely 500-m) warm temperate and tropical waters of the western Atlantic Ocean from coastal New Jersey to off southern Brazil, including [...]

Since 1995, landings of Atlantic Thread Herring ( Opisthonema oglinum) on the Florida Panhandle averaged 124 mt each spring (April-June) but declined to nearly zero in 1996-97 and 2006. To elucidate causes of recurring periods of low landings, we used generalized additive mixed models ( GAMMs) to examine the relationship between Atlantic Thread Herring catch in a trawl survey on the west-central coast of Florida and four environmental variables. Chlorophyll- a was significant in the models, indicating a direct relationship between local abundance of baitfish and their planktonic food. Temperature and depth were also significant whereas salinity was not. During 2003 and 2012, synoptic satellite-derived temperature and chlorophyll- a maps were used with the GAMMs to predict monthly spatial availability on the Florida Panhandle fishing grounds (long. 85-88o W and depth 12-25 m). The predicted monthly availability was significantly correlated with commercial catch rates (Pearson's r = 0.26, P = 0.004, d.f. = 118). We used multiple linear regression ( MLR) with lags to describe the effect of river discharge and wind (as a transport mechanism) on surface chlorophyll- a over the Panhandle fishing grounds. Discharge from local rivers was significant in all MLRs, and the Mississippi was only significant as an interaction with wind. We conclude that Atlantic Thread Herring are distributed over the Panhandle fishing grounds based on food availability that is driven by river discharge and eastward transport of Mississippi River plumes. This analysis improves our understating of baitfish dynamics, an important ecosystem component in the Gulf of Mexico. [ABSTRACT FROM AUTHOR]

The article provides information on the Ecopath-Ecosim model designed to explore the ecosystem management options in the Gulf of Mexico. The model shows good simulated agreement with time-series patterns estimated from stock assessment and relative abundance index data for many of the species and offers an explanation for apparent nonstationarity in natural mortality rates of menhaden over the historical period of 1950-2004. Furthermore, the model also predicts a policy about the impacts of fishery management, wherein the implication of policy is possible because of the explicit, multistanza representation of juvenile life histories and trophic interactions.

In December 2000 the US National Oceanic and Atmospheric Administration''s Fish Lidar (Light Detection And Ranging) system was operated from an airplane off the west coast of Florida. Schools of fish were located and their volume-backscattering coefficients, β(π), measured at the lidar wavelength of 532 nm. Concurrently, a 208 kHz echosounder was deployed from a small boat to measure the acoustic volume-backscattering coefficients, sv, of the same schools. Seven schools were characterized with both the lidar and the echosounder. The correlation between these seven pairs of β(π) and sv measurements was 0.994. A linear regression of β(π) versus sv had a negative y-intercept, which supports aerial observations of some degree of avoidance reaction of fish to the passing survey boat. The slope was slightly greater than unity, in agreement with previous calculations that the acoustic backscatter of similar fish is slightly greater than the lidar backscatter. The results of this study indicate that lidar is a suitable tool for surveying rapidly the distributions and abundances of epipelagic fish stocks in the shallow waters off the west coast of Florida. Aerial lidar surveys do not have the biases of fish-avoidance reaction potentially affecting acoustic and trawl surveys. [Copyright &y& Elsevier]

Phytoplankton blooms are increasingly conspicuous along the world’s coastlines, and the toxic effects of these blooms have become a major concern. Nutrient enrichment often causes phytoplankton blooms, which decrease water transparency, but little is known about the effects of such light regime changes on whole communities of the continental shelf. A series of simulations designed to evaluate the potential effects of shading by phytoplankton blooms on community organization were conducted using a balanced trophic model of the West Florida Shelf ecosystem and the Ecopath with Ecosim modeling approach. Many functional groups in the system were predicted to decline as benthic primary production was inhibited through shading by phytoplankton, especially when associated biogenic habitat was lost. Groups that obtain most of their energy from planktonic pathways increased when shading impact and associated structural habitat degradation were complemented by enhanced phytoplankton production. Groups predicted to decline as the result of shading by plankton blooms include seabirds, manatees, and a variety of demersal and benthic fishes and invertebrates. Some counterintuitive predictions of declines (mackerel, seabirds, and surface pelagics) resulted because these groups are somewhat dependent on benthic primary production. The overall effect of the simulated bloom-associated shading of benthic primary producers resembled a trophic cascade where the number of full cycles of biomass gains and losses was approximately equal to the number of trophic levels in the system (4.7). [Copyright &y& Elsevier]

Cu thin films and Cu 2 O microstructures were partially converted to the Metal-Organic Frameworks (MOFs) Cu 3 (BTC) 2 or Cu(TCPP) using an electrochemical process with a higher control and at milder conditions compared to the traditional solvothermal MOF synthesis. Initially, either a Cu thin film was sputtered, or different kinds of Cu or Cu 2 O microstructures were electrochemically deposited onto a conductive ITO glass substrate. Then, these Cu thin films or Cu-based microstructures were subsequently coated with a thin layer of either Cu 3 (BTC) 2 or Cu(TCPP) by controlled anodic dissolution of the Cu-based substrate at room temperature and in the presence of the desired organic linker molecules: 1,3,5-benzenetricarboxylic acid (BTC) or photoactive 4,4',4'',4'''-(Porphine-5,10,15,20-tetrayl) tetrakis(benzoic acid) (TCPP) in the electrolyte. An increase in size of the Cu micro cubes with exposed planes [100] of 38,7 % for the Cu 2 O@Cu 3 (BTC) 2 and a 68,9 % increase for the Cu 2 O@Cu(TCPP) was roughly estimated. Finally, XRD, Raman spectroscopy and UV-vis absorption spectroscopy were used to characterize the initial Cu films or Cu-based microstructures, and the obtained core-shell Cu 2 O@Cu(BTC) and Cu 2 O@Cu(TCPP) microstructures., (© 2023 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)