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The Southern Ocean, a region highly vulnerable to climate change, plays a vital role in regulating global nutrient cycles and atmospheric CO2via the biological carbon pump. Diatoms, photosynthetically active plankton with dense opal skeletons, are key to this process as their exoskeletons are thought to enhance the transfer of particulate organic carbon to depth, positioning them as major vectors of carbon storage. Yet conflicting observations obscure the mechanistic link between diatoms, opal and particulate organic carbon fluxes, especially in the twilight zone where greatest flux losses occur. Here we present direct springtime flux measurements from different sectors of the subpolar Southern Ocean, demonstrating that across large areas of the subpolar twilight zone, carbon is efficiently transferred to depth, albeit not by diatoms. Rather, opal is retained near the surface ocean, indicating that processes such as diatom buoyancy regulation and grazer repackaging can negate ballast effects of diatoms’ skeletons. Our results highlight that the presence of diatoms in surface waters of the Southern Ocean’s largest biome does not guarantee their importance as vectors for efficient carbon transfer through the subpolar twilight zone. Climate change-driven shifts in phytoplankton community composition may affect biologically sequestered carbon pools less than currently predicted.

Forces acting on aggregates depend on their properties, such as size and structure. Breakage rate, stable size, and structure of fractal aggregates in multiphase flows are strongly related to the imposed hydrodynamic forces. While these forces are prevalently viscous for finite Reynolds number conditions, flow inertia cannot be ignored, thereby requiring one to fully resolve the Navier–Stokes equations. To highlight the effect of flow inertia on aggregate evolution, numerical investigation of aggregate evolution in simple shear flow at the finite Reynolds number is conducted. The evolution of aggregates exposed to shear flow is tracked over time. Particle coupling with the flow is resolved with an immersed boundary method, and flow dynamics are solved using a lattice Boltzmann method. Particle dynamics are tracked by a discrete element method, accounting for interactions between primary particles composing the aggregates. Over the range of aggregate-scale Reynolds numbers tested, the breakage rate appears to be governed by the combined effect of momentum diffusion and the ratio of particle interaction forces to the hydrodynamic forces. For higher shear stresses, even when no stable size exists, breakage is not instantaneous because of momentum diffusion kinetics. Simulations with particle interaction forces scaled with the viscous drag, to isolate the effect of finite Reynolds hydrodynamics on aggregate evolution, show that flow inertia at such moderate aggregate Reynolds numbers has no impact on the morphology of nonbreaking aggregates but significantly favors breakage probability. This is a first-of-its-kind study that establishes the role of flow inertia in aggregate evolution. The findings present a novel perspective into breakage kinetics for systems in low but finite Reynolds number conditions.

Cancer of the parotid gland (one of a pair of large salivary glands at the side of the face) is effectively treated by a combination of surgery and radiotherapy. However, when the tumor is advanced with large size and invasion of adjacent tissue, surgery may not be possible. It is suggested that radiotherapy might be used to reduce the size of advanced tumors, and thereby permit inoperable tumors to be removed surgically. The authors describe the treatments and outcomes of 30 patients with advanced cancer of the parotid gland, who were treated first with radiotherapy, and then radical surgery. The average patient age was 60.5 years, and tumor size ranged from 2 to 12 centimeters (median of 5 centimeters). During preoperative radiotherapy, three patients experienced deterioration of their condition and could not undergo surgery. Radical surgery was performed on the remaining 27 patients. Surgery was performed by both an oral and plastic surgeons, and involved removal of the parotid gland with sacrifice of the facial nerve and overlying skin. In some cases, excision of the external ear, and all or part of the jaw bone and cheek bone was necessary. Postoperative radiotherapy was administered to 12 patients. During the 3-month to 11-year follow-up period, 3 patients were lost to follow-up, 17 died, and 7 are alive. Fourteen patients have remained disease-free or died free of disease. Recurrence of cancer in the same area occurred in 6 patients within an average period of 10.5 months after surgery. The 5-year survival was 30 percent. (Consumer Summary produced by Reliance Medical Information, Inc.)

When analyzing recrystallization kinetics data, it is extremely important to use a model, which has appropriate assumptions for nucleation and growth, including spatial distribution of nuclei, nucleation rate, growth rate, and directionality. In the present work, we reveal how advanced microstructural path modeling (MPM) can successfully fit kinetics data for the complex recrystallization of two different industrial aluminum alloys. Simpler models have failed to fit the data over the entire recrystallization period. The new model allows for spatially clustered nucleation and for different growth rates in different sample directions, whereby the grains evolve with an aspect ratio different from 1. Based on the MPM analysis, the specific nucleation and growth parameters as well as the recrystallized grain sizes are deduced, and the recrystallization characteristics of the two alloys are compared. The work demonstrates the power of quantitative metallography and the wealth of recrystallization information that may be obtained from MPM modeling of such stereological data. Novel linear impingement microstructural path model fits recrystallization data for two commercial aluminum alloys.

Categorizing people with late-onset Alzheimer’s disease into biologically coherent subgroups is important for personalized medicine. We evaluated data from five studies (total n?=?4050, of whom 2431 had genome-wide single-nucleotide polymorphism (SNP) data). We assigned people to cognitively defined subgroups on the basis of relative performance in memory, executive functioning, visuospatial functioning, and language at the time of Alzheimer’s disease diagnosis. We compared genotype frequencies for each subgroup to those from cognitively normal elderly controls. We focused on APOEand on SNPs with p?1.30). There was substantial variation across studies in the proportions of people in each subgroup. In each study, higher proportions of people with isolated substantial relative memory impairment had =1 APOEe4 allele than any other subgroup (overall p?=?1.5?×?10-27). Across subgroups, there were 33 novel suggestive loci across the genome with p?

Ocean biological processes play an important role in the global carbon cycle via the production of organic matter and its subsequent export. Often, this flux is assumed to be in steady state; however, it is dependent on nutrients introduced to surface waters via multiple mechanisms, some of which are likely to exhibit both intra‐annual and interannual variability leading to comparable variability in ocean carbon uptake. Here we test this variability using surface (5 m) inorganic nutrient concentrations from voluntary observing ships and satellite‐derived estimates of chlorophyll and net primary production. At lower latitudes, the seasonality is small, and the monthly averages of nitrate:phosphate are lower than the canonical 16:1 Redfield ratio, implying nitrogen limitation, a situation confirmed via a series of nutrient limitation experiments conducted between Bermuda and Puerto Rico. The nutrient seasonal cycle is more pronounced at higher latitudes, with clear interannual variability. Over a large area of the midlatitude North Atlantic, the winters of 2009/2010 and 2010/2011 had nitrate values more than 1μmol L−1higher than the 2002–2017 average, suggesting that during this period, the system may have shifted to phosphorus limitation. This nitrate increase meant that, in the region between 31° and 39° N, new production calculated from nitrate uptake was 20.5g C m−2in 2010, more than four times higher than the median value of the whole observing period. Overall, we suggest that substantial variability in nutrient concentrations and biological carbon uptake occurs in the North Atlantic with interannual variability apparent over a number of different time scales. Surface nitrate and phosphate concentrations have been higher after 2011 in the North Atlantic Subtropical GyreThe winter seasons of 2010 and 2011 had anomalously high concentrations of surface nitrate across the North AtlanticThis caused an up to fourfold increase in new production in the Central North Atlantic

The article provides information on Seyfert galaxies. They are spiral galaxies featuring a small, very bright nuclei embedded in rapidly moving masses of gas that are apparently being ejected from the region. Quasars are considered examples of the phenomenon seen in Seyfert galaxies. It is implied that the nuclei of ordinary galaxies share significant characteristics with the nuclei of Seyfert galaxies and with quasars.

Subantarctic Mode Water (SAMW) forms north of the Subantarctic Front, in regions of deep winter mixed layers, and is important to the absorption and storage of anthropogenic CO2and heat. Two SAMW pools exist in the Pacific, a lighter Central mode (CPSAMW), and a denser Southeast mode (SEPSAMW). Both have experienced significant interannual variability in thickness and properties in recent years. We compute mixed layer temperature and salinity budgets for the two SAMW formation regions, to determine the relative contribution of processes driving variability in the properties of mixed layers that subduct to form SAMW. The dominant drivers of temperature and salinity variability are shown to be surface fluxes, horizontal advection, and entrainment of deeper water. Salt advection into each SAMW formation region is found to be strongly correlated with changes in sea ice area in the northern Ross Sea, with lags of up to 2 years. Further correlation is found between meridional salt advection in the southeast Pacific formation regions, and sea ice area in the northern Amundsen/Bellingshausen seas, suggesting that freshwater derived from sea ice melt reaches the SEPSAMW formation region within 6 months. In 2016, strong advective freshening of the SEPSAMW formation region, linked to increased winter sea ice in the Amundsen/Bellingshausen seas, led to anomalously fresh mixed layers. However, a regime change in Antarctic sea ice in 2016 resulted in a subsequent lack of the usual advective freshening in the SEPSAMW formation region, driving increased salinity of the mixed layer the following year. Well‐mixed mode waters that form in the north of the Southern Ocean are particularly important to the ocean absorption of heat and CO2from the atmosphere. Two types of mode water form in the Pacific sector of the Southern Ocean: a Central pool and a Southeast pool. Both have shown significant year‐to‐year variability in recent decades. Variability in the regions where these waters form is shown to be due to changes in air‐sea fluxes, horizontal advection, and the upward transport of deeper water. Transport of freshwater into the mode water formation regions is shown to be correlated with year‐to‐year changes in sea ice area in the Ross Sea and in the Amundsen/Bellingshausen seas. The results suggest that it takes around 6 months for sea ice melt from the Amundsen/Bellingshausen seas to reach the southeast mode water region, and up to 2 years for freshwater from the Ross Sea to reach both mode water formation sites. In 2015, Amundsen/Bellingshausen sea ice was particularly high, leading to more freshwater being transported to the southeast mode water site the following spring/summer. A huge decrease in winter sea ice in 2016 then caused the opposite, and salinity at the formation site was unusually high. Temperature and salinity variability at Pacific Subantarctic Mode Water (SAMW) formation sites is driven by surface fluxes, advection and entrainmentFreshwater anomalies advected from the Ross Sea take up to 2 years to reach the Pacific SAMW formation regionsAnomalies in Amundsen/Bellingshausen sea ice in 2016–2017 drove salinity anomalies at the nearby southeast Pacific SAMW formation site Temperature and salinity variability at Pacific Subantarctic Mode Water (SAMW) formation sites is driven by surface fluxes, advection and entrainment Freshwater anomalies advected from the Ross Sea take up to 2 years to reach the Pacific SAMW formation regions Anomalies in Amundsen/Bellingshausen sea ice in 2016–2017 drove salinity anomalies at the nearby southeast Pacific SAMW formation site

51-1565 HT330 MARC Taylor, Peter J. Extraordinary cities: millennia of moral syndromes, world-systems and city/state relations. E. Elgar, 2013. 424p bibl indexes ISBN 9781781954805, $150.00; ISBN 9781781954829 e-book, contact publisher [...]

49-0430 GFS0 2010-20078 CIP Geographies of mobilities: practices, spaces, subjects, ed. by Tim Cresswell and Peter Merriman. Ashgate, 2011. 276p bibl index ISBN 9780754673163, $99.95; ISBN 9781409417828 e-book, contact publisher [...]

A fraction of organic carbon produced in the oceans by phytoplankton sinks storing 5–15 gigatonnes of carbon annually in the ocean interior. The accepted paradigm is that rapid aggregation of phytoplankton cells occurs, forming large, fresh particles which sink quickly; this concept is incorporated into ecosystem models used to predict the future climate. Here we demonstrate a slower, less efficient export pathway in the Eastern Tropical North Pacific. Lipid biomarkers suggest that the large, fast‐sinking particles found beneath the mixed layer are compositionally distinct from those found in the mixed layer and thus not directly and efficiently formed from phytoplankton cells. We postulate that they are formed from the in situ aggregation of smaller, slow‐sinking particles over time in the mixed layer itself. This export pathway is likely widespread where smaller phytoplankton species dominate. Its lack of representation in biogeochemical models suggests that they may be currently overestimating the ability of the oceans to store carbon if large, fast‐sinking, labile particles dominate simulated particle export. The oceans are one of the largest sinks of atmospheric carbon dioxide on our planet. One method by which this occurs is through the production of organic material (phytoplankton—plant‐like cells) in the surface ocean, which capture atmospheric carbon dioxide during photosynthesis. Eventually, the phytoplankton die and sink out of the surface ocean, transporting huge amounts of carbon to the deep ocean where it is stored for centuries or even millennia. Our current understanding is that generally, most organic material sinks quickly as large, fast‐sinking (hundreds of meters per day) particles (clumps of dead phytoplankton cells). However, in our study in the Equatorial Pacific Ocean, we were able to show that a different and much slower process occurs where phytoplankton first aggregate to smaller, slower sinking detrital particles and eventually form very degraded larger particles that sink to the deep. This has consequences for estimating ocean carbon storage as smaller particles are respired much quicker than larger particles. Thus, where they are an important part of this carbon sink, such as in the Equatorial Pacific, the proportion phytoplankton‐captured atmospheric carbon dioxide being stored in the deep ocean is likely reduced. In the Eastern Tropical North Pacific large, fast‐sinking, organic particles were refractory and not formed directly from phytoplankton cellsParticle aggregation occurred over time through the initial formation of smaller, suspended, and slow‐sinking particlesThis alternative particle formation has not been previously described and likely persists where small phytoplankton species dominate

Global city challenges: debating a concept, improving the practice, ed. by Michele Acuto and Wendy Steele. Palgrave Macmillan, 2013. 278p bibl index ISBN 9781137286864, $105.00 52-0563 HT361 2013-42160 MARC The [...]

Background.Although financing represents a critical component of health system strengthening and also a defining concern of efforts to move towards universal health coverage, many countries lack the tools and capacity to plan effectively for service scale-up. As part of a multi-country collaborative study (the Emerald project), we set out to develop, test and apply a fully integrated health systems resource planning and health impact tool for mental, neurological and substance use (MNS) disorders.Methods.A new module of the existing UN strategic planning OneHealth Tool was developed, which identifies health system resources required to scale-up a range of specified interventions for MNS disorders and also projects expected health gains at the population level. We conducted local capacity-building in its use, as well as stakeholder consultations, then tested and calibrated all model parameters, and applied the tool to three priority mental and neurological disorders (psychosis, depression and epilepsy) in six low- and middle-income countries.Results.Resource needs for scaling-up mental health services to reach desired coverage goals are substantial compared with the current allocation of resources in the six represented countries but are not large in absolute terms. In four of the Emerald study countries (Ethiopia, India, Nepal and Uganda), the cost of delivering key interventions for psychosis, depression and epilepsy at existing treatment coverage is estimated at US$ 0.06–0.33 per capita of total population per year (in Nigeria and South Africa it is US$ 1.36–1.92). By comparison, the projected cost per capita at target levels of coverage approaches US$ 5 per capita in Nigeria and South Africa, and ranges from US$ 0.14–1.27 in the other four countries. Implementation of such a package of care at target levels of coverage is expected to yield between 291 and 947 healthy life years per one million populations, which represents a substantial health gain for the currently neglected and underserved sub-populations suffering from psychosis, depression and epilepsy.Conclusions.This newly developed and validated module of OneHealth tool can be used, especially within the context of integrated health planning at the national level, to generate contextualised estimates of the resource needs, costs and health impacts of scaled-up mental health service delivery.

Several letters to the editor are presented in response to articles in previous issues including an article on Little River duck-tolling dogs in the December 3, 1951 issue, an article on Charles Francis Potter in the December 3, 1951 issue and "Back to Chancery," in the December 3, 1951 issue.

50-5072 BR526 2012-24951 CIP Wilford, Justin G. Sacred subdivisions: the postsuburban transformation of American evangelicalism. New York University, 2012. 220p bibl index afp ISBN 9780814725351, $79.00; ISBN 9780814770931 pbk, $24.00 [...]

50-3331 GF50 MARC ATLAS: geography, architecture, and change in an interdependent world, ed. by Renata Tyszczuk et al. Black Dog Publishing, 2012. 175p index afp ISBN 9781907317392 pbk, $29.95 These [...]

49-7203 HT113 2011-13425 CIP Urban theory beyond the West: a world of cities, ed. by Tim Edensor and Mark Jayne. Routledge, 2012. 382p bibl index ISBN 9780415589758, $160.00; ISBN 9780415589765 [...]

49-3579 HT168 2010-32059 CIP Shepard, Benjamin. The beach beneath the streets: contesting New York City's public spaces, by Benjamin Shepard and Greg Smithsimon. SUNY Press, 2011. 246p bibl index afp [...]

Sinking organic matter in the North Atlantic Ocean transfers 1–3 Gt carbon yr−1from the surface ocean to the interior. The majority of this exported material is thought to be in form of large, rapidly sinking particles that aggregate during or after the spring phytoplankton bloom. However, recent work has suggested that intermittent water column stratification resulting in the termination of deep convection can isolate phytoplankton from the euphotic zone, leading to export of small particles. We present depth profiles of large (>0.1 mm equivalent spherical diameter, ESD) and small (<0.1 mm ESD) sinking particle concentrations and fluxes prior to the spring bloom at two contrasting sites in the North Atlantic (61.30°N, 11.00°W and 62.50°N, 02.30°W) derived from the Marine Snow Catcher and the Video Plankton Recorder. The downward flux of organic carbon via small particles ranged from 23 to 186 mg C m−2d−1, often constituting the bulk of the total particulate organic carbon flux. We propose that these rates were driven by two different mechanisms. In the Norwegian Basin, small sinking particles likely reached the upper mesopelagic by disaggregation of larger, faster sinking particles. In the Iceland Basin, a storm deepened the mixed layer to >300 m depth, leading to deep mixing of particles as deep as 600 m. Subsequent restratification could trap these particles at depth and lead to high particle fluxes at depth without the need for aggregation (“mixed‐layer pump”). Overall, we suggest that prebloom fluxes to the mesopelagic are significant, and the role of small sinking particles requires careful consideration. Vertical depth profiles of sinking particles were collected before the spring bloomPrebloom fluxes by small particles (<0.1 mm) were similar to bloom and postbloom export ratesSmall particles were likely exported by two mechanisms: aggregation/disaggregation and deep mixing

Spinal neuroarthropathy, which is progressive destructive spinal arthropathy occurring after neurologic damage and associated loss of neuroprotective pain and proprioceptive reflexes, is described, including clinical characteristics, pathophysiology, multimodality imaging findings, and the most common imaging mimics.

Rotation curves for four spiral galaxies with recently determined Cepheid-based distances are reconsidered in terms of modified Newtonian dynamics (MOND). For two of the objects, NGC 2403 and NGC 7331, the rotation curves predicted by MOND are compatible with the observed curves when these galaxies are taken to be at the Cepheid distance. For NGC 3198, the largest distance for which reasonable agreement is obtained is 10% smaller than the Cepheid-based distance; i.e., MOND clearly prefers a smaller distance. This conclusion is unaltered when new near-infrared photometry of NGC 3198 is taken as the tracer of the stellar mass distribution. For the large Sb spiral, NGC 2841, MOND requires a distance which is at least 20% larger than the Cepheid-based distance. However, the discrepancy of the Tully-Fisher and SNIa distances with the Cepheid determination casts some doubt upon the Cepheid method in this case.

Most of the previous studies on the required critical minimum velocity to move the solid bed inside the slurry pipelines are related to the design step where the dynamics of the process are not thoroughly considered. In this paper, a general framework for on-line estimation of the critical minimum velocity is proposed and applied to the underflow stream of an important Primary Separation Vessel (PSV) in an oil sand industry. Appropriate statistical and probabilistic models are used to improve the on-line measurements and estimations. The proposed method demonstrates a satisfactory performance in detection of different conditions of the PSV operations.

Nucleation of recrystallization at large second phase particles during annealing is essential in many industrially relevant aluminum alloys. To adequately quantify the spatial distribution of such particles and their impact on nucleation in bulk materials, 3D investigations are needed. This study presents a multimodal characterization method to investigate particle stimulated nucleation in a heavily deformed AA5182 alloy. To map the spatial distribution of large second phase particles, conventional laboratory absorption contrast X-ray tomography is used, while the recrystallization nuclei are revealed by Laue micro-diffraction using synchrotron X-rays. The registration of data obtained by the two different non-destructive high-resolution experimental techniques is described. Finally, some preliminary results are presented.

In this work we study oxygen interstitial defects (Oi) in a silicon-technology-based microreactor with an integrated attenuated total internal reflection (ATR) crystal as a function of an externally applied potential by means of attenuated total internal reflection infrared spectroscopy (ATR-IR). A reduction of the 1727 cm–1OiIR absorption band is observed with increasing potential. We evidence that this band is related to the presence of Oi, which enables detection of Oiby ATR-IR spectroscopy. The observed reduction with increasing potential is ascribed to an increase in temperature, due to resistive heating of the silicon.

Hořava-Lifshitz gravity is an attempt to construct a renormalizable theory of gravity by breaking the Lorentz invariance of the gravitational action at high energies. The underlying principle is that Lorentz invariance is an approximate symmetry and its violation by gravitational phenomena is somehow hidden to present limits of observational precision. Here I point out that a simple modification of the low-energy limit of Hořava-Lifshitz gravity in its nonprojectable form can effectively camouflage the presence of a preferred frame in regions where the Newtonian gravitational field gradient is higher than cH0; this modification results in the phenomenology of modified Newtonian dynamics (MOND) at lower accelerations. As a relativistic theory of MOND, this modified Hořava-Lifshitz theory presents several advantages over its predecessors. [ABSTRACT FROM AUTHOR]

I review various ideas on MOND cosmology and structure formation beginning with non-relativistic models in analogy with Newtonian cosmology. I discuss relativistic MOND cosmology in the context of Bekenstein's theory and propose an alternative biscalar effective theory of MOND in which the acceleration parameter, a0 is identified with the cosmic time derivative of a matter coupling scalar field and cosmic CDM appears as scalar field oscillations of the auxiliary “coupling strength” field.

We first review the nonrelativistic Lagrangian theory as a framework for the MOND equation. Obstructions to a relativistic version of it are discussed leading up to TeVeS, a relativistic tensor-vector-scalar field theory which displays both MOND and Newtonian limits. The whys for its particular structure are discussed and its achievements so far are summarized.

This study tested the feasibility of using computer‐based tools for the assessment of written materials produced by dental students. Written assignments produced by three consecutive incoming dental school classes (240 students) were assessed, and the performance among and between classes was analyzed. Computerized assessment of documents produced by students in the context of their regular coursework proved to be an efficient and effective mechanism for assessing performance. Student performance, assessed as a byproduct of this research, was disappointing. The performance of all classes fell below the eleventh grade level, with some students producing written material at a level of sophistication generally expected from middle school children. Existing technology shows promise as a vehicle for enhancing the assessment of dental students’ written communication skills. The ease of use and minimal training necessary to apply this technology can help mitigate the time‐intensive nature of writing assessment. If this assessment information is then used to enhance instruction—a process inherently available through software such as WebCT—the distance between assessment and instruction may be more readily bridged through an increase in the use of technology.

In this paper the fabrication and electrical characterization of a silicon microreactor for high-temperature catalytic gas phase reactions, like Rh-catalyzed catalytic partial oxidation of methane into synthesis gas, is presented. The microreactor, realized with micromachining technologies, contains silicon nitride tubes that are suspended in a flow channel. These tubes contain metal thin films that heat the gas mixture in the channel and sense its temperature. The metal patterns are defined by using the channel geometry as a shadow mask. Furthermore, a new method to obtain Pt thin films with good adhesive properties, also at elevated temperatures, without adhesion metal is implemented in the fabrication process. Based on different experiments, it is concluded that the electrical behaviour at high temperatures of Pt thin films without adhesion layer is better than that of PtTa films. Furthermore, it is found that the temperature coefficient of resistance TCR and the resistivity of the thin films are stable for up to tens of hours when the temperature-range during operation of the microreactor is below the so-called ‘burn-in’ temperature. Experiments showed that the presented suspended-tube microreactors with heaters and temperature sensors of Pt thin films can be operated safely and in a stable way at temperatures up to 700 °C for over 20 h. This type of microreactor solves the electrical breakdown problem that was previously reported by us in flat-membrane microreactors that were operated at temperatures above 600 °C.

The new predoctoral dental education program at the University of Nevada, Las Vegas, officially began on August 26, 2002. Key concepts identified as foundations for the UNLV clinical curriculum model include Student Active Integrated Learning (SAIL), the need to actively link oral health to systemic health, a sophisticated practice management model, a focus on culturally sensitive statewide outreach, establishing a strong biomedical research base, and development of future faculty. The predoctoral program will be comprised of five general practices. Students from each of the four academic years will be assigned to a practice group; each student will be expected to provide patient care within the scope of his or her current training.

Unlike other dithiolenes, ferrocenyl-substituted dithiolenes show two low-energy absorptions of comparable intensity in the 1200 and 750 nm regions. The longest wavelength peak is strongly influenced by electron-donating or -withdrawing groups, whereas the shorter wavelength peak is much less affected. Reducing the overlap between the ferrocene groups and the dithiolenes leads to shifts of both peaks to higher energy. Increased conjugation led to a remarkable shift of the first peak but influences the second one hardly at all. Although several of the results could be used to assign the longest wavelength peak to an Fe → π* transition, we present evidence that it originates from the π system (π → π*).