On losing and recovering fisheries and marine science data

Large sums are spent annually collecting and, increasingly, electronically encoding field data, making them widely accessible. Earlier data were recorded on paper, and archived at a few institutions, which eventually discard them. Data recovery and distribution is a valuable contribution to science, as it counters the ‘shifting baseline’ syndrome and ensures long-term returns on funds society invested in data gathering. Data recovery need not be expensive. We present the data recovery from the Guinean Trawling Survey, conducted in the early 1960s off West Africa, which cost 0.2% of initial survey costs. Research and graduate training institutions, as well as funding agencies should make digital data globally available as part of their deliverables

Re-estimation of small-scale fishery catches for U.S. flag-associated island areas in the western Pacific: the last 50 years

Nearshore fisheries in the tropical Pacific play an important role, both culturally and as a reliable source of food security, but often remain under-reported in statistics, leading to undervaluation of their importance to communities. We re-estimated nonpelagic catches for Guam and the Commonwealth of the Northern Mariana Islands (CNMI), and summarize previous work for American Samoa for 1950−2002. For all islands combined, catches declined by 77%, contrasting with increasing trends indicated by reported data. For individual island entities, re-estima-tion suggested declines of 86%, 54%, and 79% for Guam, CNMI, and American Samoa, respectively. Except for Guam, reported data primarily represented commercial catches, and hence under-represented contributions by subsistence and recreational fisheries. Guam’s consistent use of creel surveys for data collection resulted in the most reliable reported catches for any of the islands considered. Our re-estimation makes the scale of under-reporting of total catches evident, and provides valuable baselines of likely historic patterns in fisheries catches

Blended IT Learning - more than know-how on the job

Lebenslange Weiterbildung, Konferenzen und Kursbesuche erhöhen den Marktwert eines Individuums. Leider passen die verfügbaren Ausbildungen selten genau auf die Situation eines bestimmten Unternehmens und lassen sich dadurch oft nicht in bare Münze umsetzen

Semidefinite Relaxations for Robust Multiview Triangulation

We propose an approach based on convex relaxations for certifiably optimal robust multiview triangulation. To this end, we extend existing relaxation approaches to non-robust multiview triangulation by incorporating a least squares cost function. We propose two formulations, one based on epipolar constraints and one based on fractional reprojection constraints. The first is lower dimensional and remains tight under moderate noise and outlier levels, while the second is higher dimensional and therefore slower but remains tight even under extreme noise and outlier levels. We demonstrate through extensive experiments that the proposed approaches allow us to compute provably optimal reconstructions even under significant noise and a large percentage of outliers

Reconstruction of Domestic Marine Fisheries Catches for Oman (1950-2015)

Domestic marine fisheries in Oman are increasingly viewed as the eventual economic alternative to the soon to be depleted oil reserves. This has galvanized the Omani government to invest in the management of its marine living resources. This study aims to provide a better estimation of Oman's domestic marine fisheries catches that can be used to improve fisheries management in the country. Using the catch reconstruction approach, total domestic marine fisheries catches by Oman are estimated for the time period 1950-2015, including reported and previously unreported large-scale and small-scale commercial catches, subsistence, and recreational catches, as well as major discards. Catches from the Omani exclave, Musandam, are estimated separately, given this governorate’s geographical separation from the rest of Oman. Reconstructed total catches increased from around 64,000 t∙year-1 in the 1950s to over 200,000 t·year-1 in the 2000s, which are overall 1.2 times the landings reported by the FAO on behalf of Oman. Fish stocks need to be sustainably managed to allow long-term economic viability. This cannot be done without the improvement of fisheries statistical systems around the world, including in Oman

Synthesis of an Ortho-Triazacyclophane: N,N\u27,N\u27\u27-Trimethyltribenzo-1,4,7-triazacyclononatriene

N,N\u27,N\u27\u27-Trimethyltribenzo-1,4,7-triazacyclononatriene has been synthesized via sequential palladium-catalyzed Buchwald-Hartwig N-arylation reactions affording the 9-membered triaza o-cyclophane in 35% overall yield. An X-ray crystal structure shows the new cyclophane to have a C(2)-symmetric saddle conformation, as compared to the crown conformation exhibited by the related carbocyclic cyclotriveratrylene (CTV)

Influence of pressure on the gasification kinetics of two high-temperature beech wood chars with CO2_{2}, H2_{2}O and its mixture

This paper presents experimental data and modeling approaches to describe the influence of CO$_{2}$ and H$_{2}$O partial pressure as well as absolute pressure on the gasification kinetics of two different beech wood chars. The chars were produced at 1400 °C (P1400) and 1600 °C (P1600) at high-heating rates and short residence times in a drop-tube reactor. The gasification experiments were conducted in a single-particle reactor with forced flow-through conditions reducing diffusional effects to a minimum. The interpretation of the experimentally determined reaction rates during gasification with CO$_{2}$, H$_{2}$O and its mixture is based on the char properties (graphitization, ash dispersion and morphology) presented in a previous publication. During gasification with CO$_{2}$, P1600 shows higher reactivity as compared to P1400 for all CO$_{2}$ partial pressures and temperatures applied. The higher reactivity of P1600 during CO$_{2}$ gasification may be explained by a CaO film on the char surface catalyzing the char-CO$_{2}$ gasification reaction. On the other hand, P1400 shows higher reactivity towards H$_{2}$O which may be evoked by the lower graphitization degree and higher specific surface area. Reaction kinetic modeling for single atmosphere gasification was successfully carried out using a power law approach. The Langmuir-Hinshelwood model, however, only gave good results where a possible saturation of the char surface at high pressure was observed. Increasing the CO$_{2}$ partial pressure during gasification in mixed CO$_{2}$/H$_{2}$O atmospheres leads to higher reactivity for both chars. The reaction rate r$_{mix}$ can be expressed by addition of the single atmosphere reaction rates in the low pressure area suggesting a separate active site mechanism. Catalytic activity of CaO increases the P1600 reactivity distinctively for lower H$_{2}$O and CO$_{2}$ partial pressures. For higher H$_{2}$O and CO$_{2}$ partial pressures, P1600 reactivity stagnates due to lower specific surface area and higher graphitization degree. Here, a common active sites mechanism can be assumed

Beckmann Rearrangement of Cyclotriveratrylene (CTV) Oxime: Tandem Beckmann-Electrophilic Aromatic Addition

The Beckmann rearrangement has been performed on the oxime of cyclotriveratrylene (CTV) with thionyl chloride affording the ring-expanded 10-membered ring amide exclusively in high yield. Modified conditions afford a helical pentacycle derived from an unusual tandem Beckmann rearrangement and electrophilic aromatic addition followed by demethylation and tautomerization