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A strong understanding of technical knowledge is necessary for all engineers, but understanding the context in which engineering work takes place is just as important. Engineering work impacts people, communities, and environments, and there is increasing recognition of the importance of preparing engineers to account for these sociocultural dimensions. The engineering curriculum needs to include both technical and sociocultural topics to prepare students as holistically competent engineers. A call for broader engineering skills is evident in ABET student outcomes, a few of which directly denote the importance of students’ ability to identify the ethical, cultural, and social impact engineers have on society. However, engineering education continues to underemphasize or omit entirely non-technical aspects of engineering practice. Technical knowledge persists as the central focus in engineering classes. Omitting sociocultural material in engineering classes can result in the development of future engineers whose designs further perpetuate social and systemic inequities, such as environmental pollution that affects vulnerable populations or inefficient designs that risk human lives. Additionally, emphasizing sociotechnical content in undergraduate engineering courses can help attract and retain a more diverse population of students who value socially relevant engineering work. A deep grounding in both technical and social skills and knowledge is particularly important in Industrial Engineering (IE), a field that focuses on analyzing data to improve systems and processes and which tends to focus more on human and business dimensions than many other engineering fields. Even so, there is little evidence to indicate that sociocultural skills and knowledge are taught in IE courses. Because the curricular focus of a field communicates to students what is and is not valued in the field, students who enter IE with a strong desire to advance social good may learn that such a goal is inconsistent with the field’s values and ultimately feel alienated or disinterested if social dimensions are not incorporated into their coursework. More insight is needed into the kinds of messages IE coursework sends about the nature of work in the field and the opportunities these courses provide for students to develop the sociotechnical knowledge and skills that are increasingly crucial in Industrial Engineering. In an effort to characterize how, if at all, core courses in IE facilitate students’ development of sociotechnical engineering skills, this research paper examines the general content of core IE courses at a predominantly white institution. This paper draws on data generated for a larger research study that leverages Holland et al.’s Figured Worlds framework to explore the messaging undergraduate engineering students receive in their classes around valued knowledge in their field. In this study, we draw on observation data leveraging recordings of seven required undergraduate courses in IE. We analyzed three randomly selected sessions from each course, with a total of 21 unique sessions observed. Our findings describe the practices that are and are not emphasized within and across required IE courses and the ways these practices are discussed. Our characterization of emphasized engineering practices provides an important foundation for understanding what is communicated to students about the nature of engineering work in their field, messaging which has substantial implications for the population of students who enter and persist in the field beyond their undergraduate studies. 

Known as a bio-limiting metal, high abundances of iron in sea water can amplify biological productivity. The growth of diatoms and other photosynthetic organisms increases, providing more food for grazing organisms like foraminifera. The net result is more organic matter in surface waters and ultimately in surface sediments. Existing satellite data show increases in ocean chlorophyll in areas affected by volcanic eruptions. We infer from this that iron derived from volcanic ash does increase biological productivity. However, the relative increase in productivity is unknown. We examined 3 sediment cores from the Equatorial Western Pacific to analyze the relationship between volcanic ash and biological productivity: RC14-44, RC14-66, and RC14-67. All contain black or dark-colored foraminifera within ash layers and white-shelled foraminifera outside ash layers. We attribute the dark material outside and inside the foraminifera to organic carbon and metals. In our cores, some foraminifera are covered in iron sulfide (FeS), which could be pyrite, and contain large amounts of carbon as well as high abundances of aluminum and silicon. We examined barium concentrations to gain further knowledge of biological productivity at specific core depths as barium is a marker for primary productivity. We found that barium levels within ash layers increased at least ten-fold. Within ash layers, we also noticed that the ashes with higher amounts of fine silt and clay sized material have the greatest increase in barium content, perhaps related to explosion size. This pattern of increases in Ba, metals and organic carbon within ash layers compared to surrounding sediments shows that volcanic ash deposition increases marine productivity. For future research, measuring markers for biological productivity like biogenic silica content and loss on ignition (LOI) within and outside ash layers would further clarify the relationship between volcanic ash deposition and biological productivity. 

Volcanic eruptions deposit Fe-bearing volcanic ash in the ocean, thereby increasing biological productivity. The increased organic matter in areas of high biological productivity uses up oxygen as this organic matter decays and sinks through the water column. Past living beings, like foraminifera, ate organic matter that was carbon-rich and sometimes had metals absorbed into their carbon, creating coatings inside and outside their shells. These coatings can tell us about how biological productivity was affected before, during, and after the volcanic eruption. The studied cores are from the northwest Pacific Ocean and are close to geologically young volcanoes that are not well understood. The two cores that we focused on were VM28-309 and VM36-15 both taken by the Vema research ship. We studied the relationship between ash deposition and biological productivity by looking at all the ash layers in both cores. We found that in most of the ash layers, there were black or dark-colored foraminifera with coatings inside and outside the shells that were often carbon-rich and sometimes metal-rich. We attribute this coating to the increase of organic matter in surface waters when there was deposition of large amounts of volcanic ash. We also found high concentrations of Barium metal in VM28-309. Barium (Ba) is a biological marker because most or all Ba originates from the organic matter contained in sediments. We found that ash layers containing the finest materials (<38 micrometers in size) had the highest Ba content. For accurate results, we must sample above and below ash layers and select more sediment cores in the area. Also, Barium corrections must be done using data on biogenic silica contents. Loss on ignition (LOI) data will give us an estimate of the total organic carbon in each sample- allowing a second direct assessment of the increase in biological productivity produced by the deposition of volcanic ash. 

Some satellite data show an increase in ocean chlorophyll in areas affected by volcanic eruptions. These increases in ocean color are thought to reflect an increase in photosynthetic activity by phytoplankton. These increases in primary production have been attributed to iron (Fe) from volcanic ash, particularly in high-latitude regions where primary productivity is limited by low Fe (the iron fertilization hypothesis). However, photosynthesis also appears to increase in the tropical ocean, for example in the Sunda and Ryukyu arcs and the Bismarck Sea, areas usually not thought to be iron limited. To examine the effects of volcanic ejecta on productivity in other areas, we examine relationships between ash deposition and biological productivity in three cores, RC14-44 (Sunda arc), VM28-309 (Ryukyu arc) and VM33-116 (Bismarck Sea). These cores contain volcanic ash layers with black or dark-colored foraminifera, different from the bright white foraminifera found outside of the ash layers. This dark coloration results primarily from organic carbon. In RC14-44, some foraminifera are coated with FeS and also contain high amounts of internal carbon. In VM28-309 and VM33-116, some foraminifera are filled with organic carbon rich materials, or have coatings rich in carbon. Occasionally, there are local enrichments in Fe within the foraminifera, indicative of extensive redox cycling. We attribute this carbon to increased biological productivity in these intervals. Barium (Ba) concentrations, a proxy for primary productivity because most or all Ba originates from organic matter contained in the sediment, is also enriched by up to 30-fold in the sediments containing ash. The ash layers with the highest amounts of fine material exhibit the largest enrichments in Ba, suggesting ash texture may influence the resulting changes in marine productivity. Overall, we find clear evidence that ash depositions increase both primary production and carbon export to sediments. Loss on ignition (LOI) and biogenic silica contents between and within ash layers, are potentially useful to further examine both the coupling between production and carbon burial, and the influence of ash deposition on phytoplankton community structure. 

We study the formation of oil droplets from an initially trapped large oil ganglion under surfactant flooding, using a microfluidic device consisting of a two-dimensional array of regularly spaced square posts. We observe that above a critical capillary number for oil mobilization, breakage of the ganglion results in the formation of either trapped patches spanning multiple pores or numerous mobile droplets that exit the device at a velocity comparable to the average flooding fluid velocity. These mobile droplets, however, are only observed when above a secondary capillary number threshold. The formation of these droplets is found to involve the simultaneous occurrence of three different passive droplet generation mechanisms where a droplet is formed as it is pulled by perpendicular fluid flow, as it is pulled by co-axial fluid flow, and or as it splits due to collision with a post. Our results show that oil breakthroughs only occur when the oil is in the form of mobile drop- lets, suggesting that droplet formation can be an important condition for the mobility of residual oil in porous media. Additionally, this post-array microfluidic device can be used for the production of monodisperse droplets whose size can be controlled by the spacing of the posts. 

Numerical analysis of the proposed nonparametric spectral density estimator. 

Site U1586 is the deepest (4692 meters below sea level [mbsl]) and farthest site from shore (170 km) drilled during Expedition 397 (Figures F1, F2, F3). It is located near the toe of the Promontório dos Príncipes de Avis at Common Midpoint (CMP) 1330 on Cruise JC89 Seismic Line 2 near the intersection of Cruise JC089 Line 3 (Figures F4, F5, F6). The continental slope environment is prone to failure and mass transport deposits (MTDs), and large disturbances are recognizable features on seismic profiles. For example, Site U1586 is between two MTDs or disturbed intervals at about 6.3 and 6.5 s two-way traveltime (TWT) on Cruise JC089 Seismic Line 2 near CMPs 1170–1250 and around CMP 1350 (Figure F5). Site U1586 is located where there is good continuity of reflectors to avoid these MTDs, but disturbances may still occur on a shorter length scale than the resolution of the seismic profiles. The target drilling depth of 350 meters below seafloor (mbsf) corresponds to the top of a package of chaotic high-amplitude reflections at 6.6 s TWT that was initially estimated to be late Miocene (~7 Ma) but was later determined biostratigraphically to be middle Miocene (~14 Ma) on the basis of shipboard micropaleontological analyses. The primary scientific objective of Site U1586 was to recover a deep distal record from a water depth of ~4690 mbsl. The sediment thickness thins toward the toe of the Promontório dos Príncipes de Avis owing to lower sedimentation rates with increased distance from shore. Interpretation of the seismic profiles suggests the sequence spans the late Miocene to Quaternary with an average sedimentation rate of 5 cm/ky. Recovery of late Miocene sediment at this site will complement sequences to be drilled during International Ocean Discovery Program (IODP) Expedition 401 to study the exchange between the Mediterranean and Atlantic for the period before, during, and after the Messinian Salinity Crisis (5.96–5.33 Ma) (Flecker et al., 2023). The sediments will also provide a history of surface and deepwater conditions through the Pliocene, including the mid-Pliocene warm period, when atmospheric CO2 was similar to today (400 ppm). Sediments recovered at Site U1586 will also be useful for studying how surface and deep oceanographic conditions responded to the intensification of Northern Hemisphere glaciation in the late Pliocene (~2.9 Ma). Site U1586 is under the influence of Lower Deep Water (LDW), which consists of Antarctic Bottom Water whose properties have been modified significantly from its origin in the high-latitude South Atlantic (Figure F7). This site's great depth may result in carbonate microfossil dissolution, although a 7.45 m piston core (JC089-5-3P) and 4.68 m kasten core (JC089-5-3K) recovered at the same location show continuous preservation of foraminifers during the last glacial stage and Holocene. Results from shipboard analyses during Expedition 397 further show that carbonate preservation and abundance of calcareous microfossils extends back to the Miocene (see Biostratigraphy). Sedimentation rates in the piston core average 11 cm/ky. The Ca/Ti and Zr/Sr measured using core scanning X-ray fluorescence (XRF) show distinct millennial events (Channell et al., 2018), with particularly notable peaks in Zr/Sr marking each of the Heinrich stadials of the last glacial period (Figure F8). Study of Site U1586 cores will permit the reconstruction of changes in ventilation and carbon storage in the deepest Atlantic on glacial–interglacial and millennial timescales with potential implications for atmospheric CO2 changes. Preservation of terrestrial biomarkers and pollen will permit reconstruction of vegetation changes in Europe. Lastly, it should be possible to correlate physical properties at Site U1586 into the Mediterranean cyclostratigraphy, thereby permitting regional climate change to be placed into a global context. 

Site U1587 is the second farthest from shore drilled during Expedition 397 and located at a water depth of 3479 meters below sea level (mbsl) (Figures F1, F2, F3). It is the second deepest site along the bathymetric transect and is bathed today by a mixture of ~75% North Atlantic Deep Water (NADW) and 25% Lower Deep Water (LDW) sourced from the Southern Ocean (Figure F4) (Jenkins et al., 2015). The mixing ratio of these water masses and their vertical position in the water column has changed in the past, which has implications for ventilation and carbon storage in the deep Atlantic Ocean. The location of Site U1587 was motivated by the clear expression of millennial climate variability in proxy records of oxygen isotopes and sea-surface temperature in nearby Piston Core MD95-2042 (Shackleton et al., 2000, 2004; Bard et al., 2000; Pailler and Bard, 2002; Davtian and Bard, 2023). Isotopic, organic biomarker, and pollen results from this core demonstrated the potential of correlating Iberian margin sediments with ice cores from Greenland and Antarctica and with European terrestrial sequences (e.g., Sánchez-Goñi et al., 2000; Margari et al., 2010, 2014, 2020). The sediment record from Site U1587 provides the opportunity to develop sediment proxy records for the Greenland and Antarctic ice cores to the base of the Quaternary and beyond. The piston core (JC089-04-2P) recovered near Site U1587 is 10.7 m long and has a sedimentation rate of 17 cm/ky (Figure F5). Ca/Ti and Zr/Sr show strong evidence of millennial variability during the last glacial cycle. The objective for Site U1587 is to study such variability for older glacial cycles throughout the Quaternary. Site U1587 is located at the intersection of Seismic Lines JC089-6 and JC089-7 (Figure F6). Although mass transport deposits or disturbed intervals are developed nearby, the continuity of reflections is good at Site U1587 (Figures F7, F8). The Upper Miocene to Quaternary sequence at Site U1587 is expanded relative to Site U1586 and is more than 500 m thick. Sedimentation rates are estimated to average ~10 cm/ky at Site U1587, or about twice that of Site U1586. We had permission from the Environmental Protection and Safety Panel (EPSP) to drill to 500 meters below seafloor (mbsf), but we requested and were granted permission to drill an additional 50 m to extend the record well into the late Miocene. Site U1587 provides an expanded sequence of late Miocene to Quaternary sediments with which to address the following objectives: Document how millennial climate variability evolved during the glacial cycles of the Quaternary and Pliocene as boundary conditions changed with the progressive intensification of Northern Hemisphere glaciation (NHG). Reconstruct the history of changing local dominance of northern-sourced versus southern-sourced deep water, as well as ventilation and carbon storage in the deep Atlantic Ocean. Determine interhemispheric phase relationships (leads/lags) by comparing the timing of proxy variables that monitor surface (Greenland) and deepwater (Antarctic) components of the climate system. Investigate climate during past interglacial periods, including the warm Pliocene period prior to the intensification of NHG. Link terrestrial, marine, and ice core records by analyzing pollen and terrestrial biomarkers that are delivered to the deep-sea environment of the Iberian margin. Recover a complete record of the time leading up to, during, and following the Messinian Salinity Crisis, which complements objectives of International Ocean Discovery Program (IODP) Expedition 401 (Flecker et al., 2023) and will permit evaluation of the causes and consequences of this remarkable event in Earth's history. Develop an orbitally-tuned age model for Site U1587 by correlating physical properties to eccentricity-modulated precession and tying them into the record of Mediterranean cyclostratigraphy.