Channels Ran Through It—The Lawrence Formation at Lone Star Lake, Douglas County, Kansas

The upper part of the Ireland Sandstone Member of the Lawrence Formation exposed in the spillway of Lone Star Lake, southwest of Lawrence, Kansas, consists of abundant pinstripe-bedded shales and siltstones; thin, lenticular sandstone and siltstone beds; and meter-scale, channel-form sandstone and mudstone lenses. Soft-sediment-deformation structures, including load casts, ball-and-pillow, and pseudonodules are abundant. The lenticular and pinstripe bedding with bipolar paleocurrents suggests tide-influenced deposition. The crosscutting, channel-form deposits are interpreted as tidal channels in an environment with low energy but rapid sedimentation. The depositional environment was a tide-dominated, muddy upper estuary cut by tidal channels. Gravitational instabilities resulting from rapid deposition of sand over saturated mud produced inverse-density gradients that resulted in soft-sediment deformation

Spitzer, Near-Infrared, and Submillimeter Imaging of the Relatively Sparse Young Cluster, Lynds 988e

We present {\it Spitzer} images of the relatively sparse, low luminosity young cluster L988e, as well as complementary near-infrared (NIR) and submillimeter images of the region. The cluster is asymmetric, with the western region of the cluster embedded within the molecular cloud, and the slightly less dense eastern region to the east of, and on the edge of, the molecular cloud. With these data, as well as with extant H$\alpha$ data of stars primarily found in the eastern region of the cluster, and a molecular $^{13}$CO gas emission map of the entire region, we investigate the distribution of forming young stars with respect to the cloud material, concentrating particularly on the differences and similarities between the exposed and embedded regions of the cluster. We also compare star formation in this region to that in denser, more luminous and more massive clusters already investigated in our comprehensive multi-wavelength study of young clusters within 1 kpc of the Sun.Comment: 21 pages, 6 tables, 13 figures. Full resolution figures at: http://astro.pas.rochester.edu/~tom/Preprints/L988e.pd

Entrepreneurship and Urban Success: Toward a Policy Consensus

Like all politics, all entrepreneurship is local. Individuals launch firms and, if successful, expand their enterprises to other locations. But new firms must start somewhere, even if their businesses are conducted largely or exclusively on the Internet. Likewise, policymakers at local and state levels increasingly recognize that entrepreneurship is the key to building and sustaining their economies\u27 growth. Although this is a seemingly obvious proposition, it represents something of a departure from past thinking about how local, state, or regional economies grow. Historically, state and local policymakers have put their energies into trying to attract existing firms from somewhere else, either to relocate to a particular area or to build new facilities there. Such smokestack chasing - or, in this cleaner era, simply firm chasing - often has degenerated into what is essentially a zero-sum game for the national economy. When one city or state offers tax breaks or other financial inducements to encourage firms to locate new plants or headquarters, and succeeds, some other city or state loses out in the process. Local, state, and regional economic development centered on entrepreneurship, however, is a fundamentally different phenomenon. The formation and growth of new firms, especially those built around new products or ways of doing things, wherever this occurs, is clearly a positive sum game, not just for the locality, but for the nation as a whole. This essay provides a guide to policymakers and citizens to what is known about the effects of various local and state policies aimed at fostering entrepreneurially driven growth. There is also much we do not know; thus, the essay identifies subjects that require further research

Multidisciplinary Baseline Assessment of Homosexual Men with and without Human Immunodeficiency Virus Infection. I. Overview of Study Design

Although much is known about the virus believed by most experts to be the cause of the acquired immunodeficiency syndrome and about its pathogenic actions, major areas of ignorance remain. Among these are the reasons for the varying time between infection with human immunodeficiency virus and development of acquired imunodeficiency syndrome, the relationship between neurologic and medical aspects of the disease, the time course of neuropsychological findings, and the prevalence of psychiatric morbidity. We assessed 124 homosexual men who were positive for human immunodeficiency virus and 84 who were negative for the virus. In this article we describe the study design, method of recruitment, and medical and demographic characteristics of the cohort, which will be followed up for 5 years

Cancer incidence in HIV-infected versus uninfected veterans: Comparison of cancer registry and ICD-9 code diagnoses

Background: Given the growing interest in the cancer burden in persons living with HIV/AIDS, we examined the validity of data sources for cancer diagnoses (cancer registry versus International Classification of Diseases, Ninth Revision [ICD-9 codes]) and compared the association between HIV status and cancer risk using each data source in the Veterans Aging Cohort Study (VACS), a prospective cohort of HIV-infected and uninfected veterans from 1996 to 2008. Methods: We reviewed charts to confirm potential incident cancers at four VACS sites. In the entire cohort, we calculated cancer-type-specific age-, sex-, race/ethnicity-, and calendar-period-standardized incidence rates and incidence rate ratios (IRR) (HIV-infected versus uninfected). We calculated standardized incidence ratios (SIR) to compare VACS and Surveillance, Epidemiology, and End Results rates. Results: Compared to chart review, both Veterans Affairs Central Cancer Registry (VACCR) and ICD-9 diagnoses had approximately 90% sensitivity; however, VACCR had higher positive predictive value (96% versus 63%). There were 6,010 VACCR and 13,386 ICD-9 incident cancers among 116,072 veterans. Although ICD-9 rates tended to be double VACCR rates, most IRRs were in the same direction and of similar magnitude, regardless of data source. Using source, all cancers combined, most viral-infection-related cancers, lung cancer, melanoma, and leukemia had significantly elevated IRRs. Using ICD-9, eight additional IRRs were significantly elevated, most likely due to false positive diagnoses. Most ICD-9 SIRs were significantly elevated and all were higher than the corresponding VACCR SIR. Conclusions: ICD-9 may be used with caution for estimating IRRs, but should be avoided when estimating incidence or SIRs. Elevated cancer risk based on VACCR diagnoses among HIV-infected veterans was consistent with other studies

Observations of Energetic-particle Population Enhancements along Intermittent Structures near the Sun from the Parker Solar Probe

Observations at 1 au have confirmed that enhancements in measured energetic-particle (EP) fluxes are statistically associated with "rough" magnetic fields, i.e., fields with atypically large spatial derivatives or increments, as measured by the Partial Variance of Increments (PVI) method. One way to interpret this observation is as an association of the EPs with trapping or channeling within magnetic flux tubes, possibly near their boundaries. However, it remains unclear whether this association is a transport or local effect; i.e., the particles might have been energized at a distant location, perhaps by shocks or reconnection, or they might experience local energization or re-acceleration. The Parker Solar Probe (PSP), even in its first two orbits, offers a unique opportunity to study this statistical correlation closer to the corona. As a first step, we analyze the separate correlation properties of the EPs measured by the Integrated Science Investigation of the Sun (IS⊙IS) instruments during the first solar encounter. The distribution of time intervals between a specific type of event, i.e., the waiting time, can indicate the nature of the underlying process. We find that the IS⊙IS observations show a power-law distribution of waiting times, indicating a correlated (non-Poisson) distribution. Analysis of low-energy (~15 – 200 keV/nuc) IS⊙IS data suggests that the results are consistent with the 1 au studies, although we find hints of some unexpected behavior. A more complete understanding of these statistical distributions will provide valuable insights into the origin and propagation of solar EPs, a picture that should become clear with future PSP orbits

Arctic tundra shrubification: a review of mechanisms and impacts on ecosystem carbon balance

Vegetation composition shifts, and in particular, shrub expansion across the Arctic tundra are some of the most important and widely observed responses of high-latitude ecosystems to rapid climate warming. These changes in vegetation potentially alter ecosystem carbon balances by affecting a complex set of soil-plant-atmosphere interactions. In this review, we synthesize the literature on (a) observed shrub expansion, (b) key climatic and environmental controls and mechanisms that affect shrub expansion, (c) impacts of shrub expansion on ecosystem carbon balance, and (d) research gaps and future directions to improve process representations in land models. A broad range of evidence, including in-situ observations, warming experiments, and remotely sensed vegetation indices have shown increases in growth and abundance of woody plants, particularly tall deciduous shrubs, and advancing shrublines across the circumpolar Arctic. This recent shrub expansion is affected by several interacting factors including climate warming, accelerated nutrient cycling, changing disturbance regimes, and local variation in topography and hydrology. Under warmer conditions, tall deciduous shrubs can be more competitive than other plant functional types in tundra ecosystems because of their taller maximum canopy heights and often dense canopy structure. Competitive abilities of tall deciduous shrubs vs herbaceous plants are also controlled by variation in traits that affect carbon and nutrient investments and retention strategies in leaves, stems, and roots. Overall, shrub expansion may affect tundra carbon balances by enhancing ecosystem carbon uptake and altering ecosystem respiration, and through complex feedback mechanisms that affect snowpack dynamics, permafrost degradation, surface energy balance, and litter inputs. Observed and projected tall deciduous shrub expansion and the subsequent effects on surface energy and carbon balances may alter feedbacks to the climate system. Land models, including those integrated in Earth System Models, need to account for differences in plant traits that control competitive interactions to accurately predict decadal- to centennial-scale tundra vegetation and carbon dynamics

Small-scale Magnetic Flux Ropes in the First two Parker Solar Probe Encounters

Small-scale magnetic flux ropes (SFRs) are a type of structures in the solar wind that possess helical magnetic field lines. In a recent report (Chen & Hu 2020), we presented the radial variations of the properties of SFR from 0.29 to 8 au using in situ measurements from the Helios, ACE/Wind, Ulysses, and Voyager spacecraft. With the launch of the Parker Solar Probe (PSP), we extend our previous investigation further into the inner heliosphere. We apply a Grad-Shafranov-based algorithm to identify SFRs during the first two PSP encounters. We find that the number of SFRs detected near the Sun is much less than that at larger radial distances, where magnetohydrodynamic (MHD) turbulence may act as the local source to produce these structures. The prevalence of Alfvenic structures significantly suppresses the detection of SFRs at closer distances. We compare the SFR event list with other event identification methods, yielding a dozen well-matched events. The cross-section maps of two selected events confirm the cylindrical magnetic flux rope configuration. The power-law relation between the SFR magnetic field and heliocentric distances seems to hold down to 0.16 au.Comment: Accepted by ApJ on 2020 Sep 1