California Maritime Academy

Anthropogenic activities are altering total nutrient loads to many estuaries and freshwaters, resulting in high loads not only of total nitrogen (N), but in some cases, of chemically reduced forms, notably . Long thought to be the preferred form of N for phytoplankton uptake, may actually suppress overall growth when concentrations are sufficiently high. has been well known to be inhibitory or repressive for uptake and assimilation, but the concentrations of that promote vs. repress uptake, assimilation, and growth in different phytoplankton groups and under different growth conditions are not well understood. Here, we review N metabolism first in a “generic” eukaryotic cell, and the contrasting metabolic pathways and regulation of and when these substrates are provided individually under equivalent growth conditions. Then the metabolic interactions of these substrates are described when both are provided together, emphasizing the cellular challenge of balancing nutrient acquisition with photosynthetic energy balance in dynamic environments. Conditions under which dissipatory pathways such as dissimilatory / reduction to and photorespiration that may lead to growth suppression are highlighted. While more is known about diatoms, taxon-specific differences in and metabolism that may contribute to changes in phytoplankton community composition when the composition of the N pool changes are presented. These relationships have important implications for harmful algal blooms, development of nutrient criteria for management, and modeling of nutrient uptake by phytoplankton, particularly in conditions where eutrophication is increasing and the redox state of N loads is changing.

Abstract This article seeks to improve our grasp of the societal foundations of US foreign policy by examining how race and gender - two fundamental dimensions of social stratification of US society - affect support for military force in the pursuit of external objectives. It is generally appreciated that, in the United States, women are less inclined to support armed intervention than are men, and feminist theory provides some foundation for explaining the gap. It is less widely recognized that a similar gap separates the attitudes of African-Americans and white Americans, but there is little in the social science literature to suggest why this should be so. The authors examine a number of possible explanations for the parallel, focusing both on attributes that are specific to women and blacks, and on one common to both groups (a high level of political alienation) but not shared by white men. They conclude that, while alienation partially accounts for the parallel attitudes toward force, properties specific to the two demographic groups nevertheless carry part of the burden for explaining their shared relative aversion to military intervention.

This review article primarily focuses on the research on inclusion of carbon-based additives into the electrodes to increase the efficiency of lead-acid (LA) batteries . The carbon additives have shown a great promise to reduce the sulfation on the electrodes under high-rate partial state of charge (HRPSoC) and increase the cycle life of LA batteries. It is found that a significant amount of literature is focused on the inclusion of additives on the negative active material (NAM) electrode when compared to the positive active material (PAM) electrode. The weight percent (wt.%) and particle size of carbon additives was found to influence the cycle life of the batteries. The performance of LA batteries has also been compared to the lithium-ion (Li-ion) batteries that have gained prominence in recent years due to their higher cycle life under deep discharge applications. The comparison suggested that even though Li-ion batteries have emerged as a contender in a wide range of applications, LA batteries will continue to have a significant market share for the next several decades due to their merits in the existing off-grid applications, low initial cost, and higher recyclability . The literature study also informed that there is a dearth in theoretical studies that can provide better understanding of the effect of carbon additives on the LA batteries.

This paper examines the subject of cost allocation in a multiple product inventory system, allowing for consolidation of shipments. If we order multiple items using an economic order quantity (EOQ) policy, and consolidate shipments, part of the ordering cost is shared, and part is specific to each item; we want to find the consolidation choice with optimal total cost and divide the cost fairly among the individual items. Such a fair division is central to a costing system in which no group of items subsidizes the others; there are no free riders! We use a cooperative inventory game to determine when this can be done. This game is usually not concave, so we want to know what consolidation combinations determine when this cost can be fairly divided, using the core of the game. We prove that consolidation of all the items is cheaper exactly if there are fair cost allocations (core of the game is not empty), which happens when the portion of the ordering cost common to all items is not too small. We further show how sensitive the nonempty core result is to adjustments in the cost parameters and show how to determine a threshold value for the shared ordering cost, which assures the existence of a fair cost allocation.

BACKGROUND: Previously we demonstrated the safety and patency of a magnetic compression anastomosis (magnamosis). We present the further development of this technique, with specific focus on optimizing device design for minimally invasive magnamosis. STUDY DESIGN: The magnamosis device was designed to incorporate 3 features: 2 convex-concave radially symmetric halves that magnetically self-align, a central channel for immediate patency, and specially engineered radial topography of the mating surfaces to promote gradual remodeling. Each symmetrical half consists of a ring-shaped neodymium-iron-boron magnet encased in polycarbonate casing. Twenty-one young adult pigs underwent either magnetic gastrojejunostomy (n = 13) or jejunojejunostomy (n = 8). Animals were euthanized at 1, 2, 4, and 6 weeks after operation. Anastomoses were studied with contrast radiography, burst pressure, and histology. RESULTS: Gastrojejunostomy: In all animals with successful placement of magnets, anastomoses were patent by contrast fluoroscopy, well healed by histologic examination, and showed excellent burst strength. Jejunojejunostomy: All animals had uneventful clinical courses, indicating that the magnamosis with immediate patency functioned properly without device dislodgement. At sacrifice, all magnamoses were patent, well healed by histology, and had burst strengths that equaled or exceeded that of traditional stapled anastomoses. CONCLUSIONS: Minimally invasive placement of a custom magnetic device in the stomach and jejunum allows intraluminal self-alignment and subsequent compression anastomosis over 3 to 10 days. The magnamosis is immediately patent and develops strength equal to or greater than that of hand-sewn or stapled anastomoses. Magnamosis is effective in the pig model, and may be a safe, effective, and minimally invasive alternative to current anastomotic strategies in humans.

We demonstrate a method for determining the full three-dimensional molecular-frame photoelectron angular distribution in polyatomic molecules using methane as a prototype. Simultaneous double Auger decay and subsequent dissociation allow measurement of the initial momentum vectors of the ionic fragments and the photoelectron in coincidence, allowing full orientation by observing a three-ion decay pathway, (H+, H+, CH2(+)). We find the striking result that at low photoelectron energies the molecule is effectively imaged by the focusing of photoelectrons along bond directions.

This is a qualitative study about the information competencies that employers seek in university graduates and the skills which graduates demonstrate when they enter the workplace. Included are findings from interviews with 23 US employers and focus groups with a total of 33 recent graduates from four US colleges and universities. Employers said they recruited graduates for their online searching skills but once graduates joined the workplace they rarely used the traditional, low-tech research competencies that their employers also needed. Graduates said that they used skills from university for evaluating and managing published content; yet most graduates still needed to develop adaptive strategies to save time and work more efficiently. A preliminary model compares information problems in the university with those of the workplace. Opportunities are identified for preparing students to succeed beyond the academy in the workplaces of today and tomorrow.

Estuaries worldwide are undergoing changes to patterns of aquatic productivity because of human activities that alter flow, impact sediment delivery and thus the light field, and contribute nutrients and contaminants like pesticides and metals. These changes can influence phytoplankton communities, which in turn can alter estuarine food webs. We used multiple approaches-including high-resolution water quality mapping, synoptic sampling, productivity and nitrogen uptake rates, Lagrangian parcel tracking, enclosure experiments and bottle incubations-over a short time period to take a “spatial snapshot” of conditions in the northern region of the San Francisco Estuary (California, USA) to examine how environmental drivers like light availability, nutrients, water residence time, and contaminants affect phytoplankton abundance and community attributes like size distribution, taxonomic structure, and nutrient uptake rates. Zones characterized by longer residence time (15–60 days) had higher chlorophyll-a concentrations (9 ± 4 µg L−1) and were comprised primarily of small phytoplankton cells (<5 µm, 74 ± 8%), lower ammonium concentrations (1 ± 0.8 µM), higher nitrate uptake rates, and higher rates of potential carbon productivity. Conversely, zones characterized by shorter residence time (1–14 days) had higher ammonium concentration (13 ± 5 µM) and lower chlorophyll-a concentration (5 ± 1 µg L−1) with diatoms making up a larger percent contribution. Longer residence time, however, did not result in the accumulation of large (>5 µm) cells considered important to pelagic food webs. Rather, longer residence time zones had a phytoplankton community comprised primarily of small cells, particularly picocyanobacteria that made up 38 ± 17% of the chlorophyll-a – nearly double the concentration seen in shorter residence time zones (22 ± 7% picocyanobacterial of chlorophyll-a). Our results suggest that water residence time in estuaries may have an effect as large or larger than that experimentally demonstrated for light, contaminants, or nutrients.

The effect of equivalent additions of nitrogen (N, 30-40 μM-N) in different forms (ammonium, NH4+, and nitrate, NO3-) under conditions of different light exposure on phytoplankton community composition was studied in a series of four, 5-day enclosure experiments on water collected from the nutrient-rich San Francisco Bay Delta over two years. Overall, proportionately more chlorophyll a and fucoxanthin (generally indicative of diatoms) was produced per unit N taken up in enclosures enriched with NO3- and incubated at reduced (~15% of ambient) light intensity than in treatments with NO3- with high (~60% of ambient) light exposure or with NH4+ under either light condition. In contrast, proportionately more chlorophyll b (generally indicative of chlorophytes) and zeaxanthin (generally indicative of cyanobacteria) was produced in enclosures enriched with NH4+ and incubated under high light intensity than in treatments with low light or with added NO3- at either light level. Rates of maximal velocities (Vmax) of uptake of N substrates, measured using 15N tracer techniques, in all enclosures enriched with NO3- were higher than those enriched with NH4+. Directionality of trends in enclosures were similar to phytoplankton community shifts observed in transects of the Sacramento River to Suisun Bay, a region in which large changes in total N quantity and form occur. These data substantiate the growing body of experimental evidence that dichotomous microbial communities develop when enriched with the same absolute concentration of oxidized vs. reduced N forms, even when sufficient N nutrient was available to the community prior to the N inoculations.

Sea level rise has destructive material impacts on coastal communities and low-lying nations. While it is largely perceived and experienced via these impacts, the level of the sea is less often thought about as a political surface. The boundary where land and sea intersect is determined by the ocean’s height, manifesting materially as a realm of coastal features and produced politically as baselines. Defined through international treaties, baselines are the low-water line upon which national boundaries are traced. Yet, this line between adjoining mediums of land and sea is much more physically blurred and dynamic than represented politically and legally. The difficulties of delimiting a coastline, a phenomenon referred to as the Coastline Paradox, means the measurement of a coastline is dependent on the ruler used, an entanglement of instrument and measurement. As rising sea levels encroach on physical coastlines, they are also impacting legal baselines, shifting national terrestrial and maritime borders inland posing existential dilemmas to island and low-lying nations. This paper examines how the concept of sea level was constructed scientifically and is enrolled in the legal demarcation of territorial borders, with the goal of examining how sea level rise politically marks a climatically changing world.

Molecular engineering at the organic/inorganic interface enables robust bottom-up design of solution processable p- and n-type hybrid nanostructures for thermoelectrics.

Maritime piracy has been a challenge for mariners as long as ships have gone to sea. In ancient times, Julius Caesar was captured and held for ransom by pirates. More recently, but still in the historical past, pirates have challenged merchant shipping from the Spanish Main to the Barbary Coast, and in Asia the famous 'pirate queen' Cheng I Sao commanded a fleet of hundreds of vessels.

There is a growing global trend towards achieving net-zero emissions of greenhouse gases from port operations as consumers and governments become increasingly aware of the impacts of global climate change and ongoing environmental justice issues. However, the existing literature on the topic of zero-emissions ports is broad-based and focuses mainly on technology feasibility. Specifically, it provides insufficient guidance on how ports can best transition to zero emissions. To address this research gap, this review article examines the ongoing zero-emissions planning documents and demonstration projects at the Ports of Los Angeles and Long Beach and presents the key lessons learned from those efforts to accelerate the adoption of zero-emissions cargo handling equipment in California. Increasingly, the Ports of Los Angeles and Long Beach are emerging as leaders with a sustainable circular strategy by implementing zero-emissions cargo handling equipment projects at a higher rate than any other ports in California, making these two ports an ideal case study to evaluate their endeavors to transition their operations to zero emissions. The findings of this review study suggest that transitioning to zero-emissions cargo handling equipment across all California ports by 2035 is best achievable with: 1) a stronger collaboration between all key stakeholders, 2) the development of statewide regulations, 3) accelerated technology commercialization through increased demonstration projects and infrastructure standardization, 4) improved funding processes, 5) enhanced workforce training, and 6) increased resiliency planning. Although this evaluation and recommendations are largely California-specific, this article can be useful to policy-and decision-makers around the world for transitioning to sustainable, net-zero emissions ports.

This paper develops a comparative framework for the design of an actuated inertial appendage for planar reorientation. We define the Inertial Reorientation template, the simplest model of this behavior, and leverage its linear dynamics to reveal the design constraints linking a task with the body designs capable of completing it. As practicable inertial appendage designs lead to physical bodies that are generally more complex, we advance a notion of “anchoring” whereby a judicious choice of physical design in concert with an appropriate control policy yields a system whose closed loop dynamics are sufficiently captured by the template as to permit all further design to take place in its far simpler parameter space. This approach is effective and accurate over the diverse design spaces afforded by existing platforms, enabling performance comparison through the shared task space. We analyze examples from the literature and find advantages to each body type, but conclude that tails provide the highest potential performance for reasonable designs. Thus motivated, we build a physical example by retrofitting a tail to a RHex robot and present empirical evidence of its efficacy.\nFor more information: Kod*lab

This paper develops a comparative framework for the design of actuated inertial appendages for planar aerial reorientation. We define the inertial reorientation template, the simplest model of this behavior, and leverage its linear dynamics to reveal the design constraints linking a task with the body designs capable of completing it. As practicable inertial appendage designs lead to morphology that is generally more complex, we advance a notion of “anchoring,” whereby a judicious choice of physical design in concert with an appropriate control policy yields a system whose closed-loop dynamics are sufficiently captured by the template to permit all further designs to take place in its far simpler parameter space. This approach is effective and accurate over the diverse design spaces afforded by existing platforms, enabling a performance comparison through the shared task space. We analyze examples from the literature and find advantages to each body type, but conclude that tails provide the highest potential performance for reasonable designs. Thus motivated, we build a physical example by retrofitting a tail to a RHex robot and present empirical evidence of its efficacy.

We examine cooperative games in supply-chain management termed Inventory Games. Supply-chain management has non-cooperative and cooperative interactions between the participating players. We provide a concise survey of cooperative inventory games in the form of extensions on two basic problems. For deterministic games, Economic Order Quantity-like policies with joint replenishment are of primary interest. For stochastic games we examine Newsvendor-like centralization games and their extensions. We conclude with a short summary of a dynamic Newsvendor realization game and directions for further research.

Rare spring blooms, > 20 μg l− 1 chlorophyll a, were observed in the San Francisco Bay Delta during the drought year of 2014 in both the upper Sacramento River and in Suisun Bay. The upper Sacramento River bloom was dominated by chlorophytes, but biomass and photosynthetic efficiency (based on variable fluorescence, Fv/Fm) precipitously declined downstream when cells were exposed to sewage effluent and NH4+ levels > 70 μM-N. Further downriver, substantial rates of nitrification occurred, based on increasing levels of NO3− and NO2− in proportion to decreasing NH4+ concentrations, reducing NH4+ levels to < 10 μM-N. The other major tributary, the San Joaquin River, had extremely high nutrient levels (NO3− > 400 μM-N, PO43 − > 13 μM-P, but NH4+ ~ 2 μM-N), very low chlorophyll a levels (~ 3 μg L− 1) and low Fv/Fm values, but elevated bacterial production, suggesting presence of an algal inhibitor, possibly an herbicide. Both rivers converge above Suisun Bay, where elevated NO3− (> 50 μM-N), sufficient PO43 − (> 3 μM-P), and reduced NH4+ levels (as low as 6 μM-N), and reduced flow created conditions conducive to a spatially large and physiologically healthy (elevated Fv/Fm) diatom bloom dominated by the species Entomoneis sp. We conceptualize this bloom as a “window of opportunity” response by these diatoms to multiple factors promoted by the drought, including longer residence time for cell growth and biomass accumulation, and longer time for in-river nitrification to occur, reducing sewage-derived NH4+ to a level where diatoms could access NO3− for uptake and growth. We suggest that management practices that favor higher rates of flow may narrow the “window of opportunity” for phytoplankton growth, potentially leading to low productivity and food limitation for fish. Under high flow, a condition of “washout” may develop where both chlorophyll and unassimilated nutrients are transported out of the bay, and the phytoplankton that do develop are less favorable in terms of community composition for supporting the upper food web.

Harmful blooms of the cyanobacterium Microcystis sp. have become increasingly pervasive in the San Francisco Estuary Delta (USA) since the early 2000s and their rise has coincided with substantial decreases in several important fish species. Direct and indirect effects Microcystis blooms may have on the Delta food web were investigated. The Microcystis population was tracked for 2 years at six sites throughout the Delta using quantitative PCR. High-throughput amplicon sequencing and colony PCR sequencing revealed the presence of 10 different strains of Microcystis, including 6 different microcystin-producing strains. Shotgun metagenomic analysis identified a variety of Microcystis secondary metabolite pathways, including those for the biosynthesis of: aeruginosin, cyanopeptolin, microginin, microviridin and piricyclamide. A sizable reduction was observed in microbial community diversity during a large Microcystis bloom (H' = 0.61) relative to periods preceding (H' = 2.32) or following (H' = 3.71) the bloom. Physicochemical conditions of the water column were stable throughout the bloom period. The elevated abundance of a cyanomyophage with high similarity to previously sequenced isolates known to infect Microcystis sp. was implicated in the bloom's collapse. Network analysis was employed to elucidate synergistic and antagonistic relationships between Microcystis and other bacteria and indicated that only very few taxa were positively correlated with Microcystis.

ABSTRACT In this study, we present the first characterization of pure PEDOT:PSS aerogels fabricated via a facile and reproducible freeze–drying technique using no additional crosslinking agents, and it is demonstrated that these materials provide a promising path to new classes of polymeric thermoelectric materials. The morphology, chemical composition, and thermoelectric properties of these robust and mechanically stable aerogels were investigated upon treatment with ethylene glycol. By direct comparison to fully dense PEDOT:PSS thick films, it is shown that the electronic portion of thermoelectric transport in PEDOT:PSS was remarkably unaffected by morphological porosity, presenting exciting opportunities for novel soft materials that simultaneously integrate thermoelectric behavior while also capitalizing on the high surface area scaffolding accessible in such aerogel architectures. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44070.

An emerging class of materials that are hybrid in nature is propelling a technological revolution in energy, touching many fundamental aspects of energy-generation, storage, and conservation. Hybrid materials combine classical inorganic and organic components to yield materials that manifest new functionalities unattainable in traditional composites or other related multicomponent materials, which have additive function only. This Research News article highlights the exciting materials design innovations that hybrid materials enable, with an eye toward energy-relevant applications involving charge, heat, and mass transport.