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Studies of insect temporal trends must account for the complex sampling histories inherent to many long-term monitoring efforts
Get PDFCrossley et al. (2020)1 examine patterns of change in insect abundance and diversity across US Long-Term Ecological Research (LTER) sites, concluding “a lack of overall increase or decline”. This is notable if true, given mixed conclusions in the literature regarding the nature and ubiquity of insect declines across regions and insect taxonomic groups2–6. The data analyzed, downloaded from and collected by US LTER sites, represent unique time series of arthropod abundances. These long-term datasets often provide critical insights, capturing both steady changes and responses to sudden unpredictable events. However, a number of the included datasets are not suitable for estimating long-term observational trends because they come from experiments or have methodological inconsistencies. Additionally, long-term ecological datasets are rarely uniform in sampling effort across their full duration as a result of the changing goals and abilities of a research site to collect data7. We suggest that Crossley et al.’s results rely upon a key, but flawed, assumption, that sampling was collected “in a consistent way over time within each dataset”. We document problems with data use prior to statistical analyses from eight LTER sites due to datasets not being suitable for long-term trend estimation and not accounting for sampling variation, using the Konza Prairie (KNZ) grasshopper dataset (CGR022) as an example
Modular Organization of Engulfment Receptors and Proximal Signaling Networks: Avenues to Reprogram Phagocytosis
Get PDFTransmembrane protein engulfment receptors expressed on the surface of phagocytes engage ligands on apoptotic cells and debris to initiate a sequence of events culminating in material internalization and immunologically beneficial outcomes. Engulfment receptors are modular, comprised of functionally independent extracellular ligation domains and cytosolic signaling motifs. Cognate kinases, adaptors, and phosphatases regulate engulfment by controlling the degree of receptor activation in phagocyte plasma membranes, thus acting as receptor-proximal signaling modules. Here, we review recent efforts to reprogram phagocytes using modular synthetic receptors composed of antibody-based extracellular domains fused to engulfment receptor signaling domains. To aid the development of new phagocyte reprogramming methods, we then define the kinases, adaptors, and phosphatases that regulate a conserved family of engulfment receptors. Finally, we discuss current challenges and opportunities for the field
Magnetic field tuning of mechanical properties of ultrasoft PDMS-based magnetorheological elastomers for biological applications
Get PDFWe report tuning of the moduli and surface roughness of magnetorheological elastomers (MREs) by varying applied magnetic field. Ultrasoft MREs are fabricated using a physiologically relevant commercial polymer, SylgardTM 527, and carbonyl iron powder (CIP). We found that the shear storage modulus, Young\u27s modulus, and root-mean-square surface roughness are increased by ∼41×, ∼11×, and ∼11×, respectively, when subjected to a magnetic field strength of 95.5 kA m−1. Single fit parameter equations are presented that capture the tunability of the moduli and surface roughness as a function of CIP volume fraction and magnetic field strength. These magnetic field-induced changes in the mechanical moduli and surface roughness of MREs are key parameters for biological applications
Tracing the patterns: fields, villages, and burial places in Lebanon
Get PDFArchaeological research in Lebanon often focuses on settlement from the Bronze Age to Romanperiods, while surrounding landscapes, earlier and later periods are under-represented. Largedatasets collecting information from all periods and site types, such as the EndangeredArchaeology in the Middle East and North Africa (EAMENA) database, address this imbalance.EAMENA predominantly uses satellite imagery to identify archaeological sites and the threatsposed to them, leading to the recognition of many previously unpublished sites, includingabandoned buildings and agricultural terraces. Here we explore how such data can be used totrace patterns of settlement and landscape use. Transects running from coast to uplands innorthern and southern Lebanon are compared: the results show profound differences betweennorth and south, and between coastal and inland zones. The importance of large, holisticdatasets for previously understudied site types and periods in piecing together past patterns ofland use, subsistence economies, burial traditions and change over time are demonstrated
Menschlichkeit in der Zauberwelt: Walter Beck und seine DEFA-Märchenfilme aus dem Atelier
No full textText and Images of Authority: The Inscribed Seals from the Persepolis Fortification Archive
Get PDFThe Persepolis Fortification archive, a large archive of administrative tablets dating to the early years of Darius I (509-493 BCE), preserves impressions of over 4,000 distinct and legible seals. 174 of these approximately 4,000 seals carry both figural imagery and text in their designs. This dissertation presents the inscribed seals corpus from the Fortification archive for the first time, thus laying the groundwork for future studies on inscribed seals from Persepolis.
Inscribed seals offer myriad avenues of investigation. In the present study, we focus on three main features of inscribed seals: 1) the languages and formulae of the inscriptions; 2) the thematic types and compositional formulae of the figural imagery; 3) the methods of presenting the inscriptions and placing them in designs. Clear patterns emerge when we trace these features according to the language(s) of the seal inscriptions. Moreover, we discuss the ways in which the figural imagery of the inscribed seals varies from that of the overall glyptic corpus from the Fortification archive.
Owing to their archival context, the inscribed seals from the Fortification archive present a special opportunity to link some seals with the officials and/or offices who used them. By considering the inscribed seals in tandem with the documents to which they are applied, we illuminate some of the ways in which inscribed seals can be linked with their user(s). In doing so, we explore the socio-historical aspects of inscribed seals, noting particular glyptic patterns according to particular types of offices/administrators.
This study also highlights the ways in which other glyptic practices in the 1st millennium BCE may have influenced Persepolitan inscribed seals. Special attention is given to the Neo-Assyrian, Late Neo-Elamite, and Late Babylonian glyptic traditions. By examining these connections, we reveal also the distinctively Achaemenid features of inscribed seals from the Fortification archive
Floating Roots: Agnes Varda\u27s Uncle Yanco
Get PDFThis article traces one source of Agnès Varda\u27s artistic inspiration to Jean “Yanco” Varda, the subject of her 1967 short film Uncle Yanco (US/France). Jean Varda was a peripatetic artist who lived on a houseboat and was part of a bohemian circle that included Henry Miller, Anaïs Nin, Alan Watts, and other luminaries of the San Francisco counterculture. Both Vardas were gleaners and artists. The author argues that both saw the imagination as a place where matter and spirit were reconciled. The article builds on previous work about Varda\u27s The Gleaners and I (Les glaneurs et la glaneuse, France, 2000), exploring Varda\u27s materialist feminism and her use of earthly and tactile materials. The author focuses not only on matter but also on the imagination and the intangible images, colors, and forms that are prominent in her oeuvre, arguing that Yanco served as a muse to his niece
Sex differences in stress-induced sleep deficits
Get PDFSleep disruptions are hallmarks in the pathophysiology of several stress-related disorders, including Major Depressive Disorder (MDD) and Post-Traumatic Stress Disorder (PTSD), both known to disproportionately affect female populations. Although previous studies have attempted to investigate disordered sleep in women, few studies have explored and compared how repeated stress affects sleep in both sexes in either human or animal models. We have previously shown that male rats exhibit behavioral and neuroendocrine habituation to 5 days of repeated restraint, whereas females do not; additional days of stress exposure are required to observe habituation in females. This study examined sex differences in sleep measures prior to, during, and after repeated restraint stress in adult male and female rats. Our data reveal that repeated stress increased time spent awake and decreased slow-wave sleep (SWS) and REM sleep (REMS) in females, and these effects persisted over 2 days of recovery. In contrast, the effects of stress on males were transient. These insomnia-like symptoms were accompanied by a greater number of exaggerated motor responses to waking from REMS in females, a phenotype similar to trauma-related nightmares. In sum, these data demonstrate that repeated stress produces disruptions in sleep that persist days after the stress is terminated in female rats. These disruptions in sleep produced by 5 days of repeated restraint may be due to their lack of habituation