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The Drosophila adult midgut is a model epithelial tissue composed of a few major cell types with distinct regional identities. One of the limitations to its analysis is the lack of tools to manipulate gene expression based on these regional identities. To overcome this obstacle, we applied the intersectional split-GAL4 system to the adult midgut and report 653 driver combinations that label cells by region and cell type. We first identified 424 split-GAL4 drivers with midgut expression from ∼7300 drivers screened, and then evaluated the expression patterns of each of these 424 when paired with three reference drivers that report activity specifically in progenitor cells, enteroendocrine cells, or enterocytes. We also evaluated a subset of the drivers expressed in progenitor cells for expression in enteroblasts using another reference driver. We show that driver combinations can define novel cell populations by identifying a driver that marks a distinct subset of enteroendocrine cells expressing genes usually associated with progenitor cells. The regional cell type patterns associated with the entire set of driver combinations are documented in a freely available website, providing information for the design of thousands of additional driver combinations to experimentally manipulate small subsets of intestinal cells. In addition, we show that intestinal enhancers identified with the split-GAL4 system can confer equivalent expression patterns on other transgenic reporters. Altogether, the resource reported here will enable more precisely targeted gene expression for studying intestinal processes, epithelial cell functions, and diseases affecting self-renewing tissues.

The most abundant natural biopolymer on earth, cellulose fiber, may offer a highly efficient, low-cost, and chemical-free option for wastewater treatment. Cellulose is widely distributed in plants and several marine animals. It is a carbohydrate polymer consisting of β-1,4-linked anhydro-D-glucose units with three hydroxyl groups per anhydroglucose unit (AGU). Cellulose-based materials have been used in food, industrial, pharmaceutical, paper, textile production, and in wastewater treatment applications due to their low cost, renewability, biodegradability, and non-toxicity. For water treatment in the oil and gas industry, cellulose-based materials can be used as adsorbents, flocculants, and oil/water separation membranes. In this review, the uses of cellulose-based materials for wastewater treatment in the oil & gas industry are summarized, and recent research progress in the following aspects are highlighted: crude oil spill cleaning, flocculation of solid suspended matter in drilling or oil recovery in the upstream oil industry, adsorption of heavy metal or chemicals, and separation of oil/water by cellulosic membrane in the downstream water treatment. Keywords: Cellulose, Wastewater treatment, Petroleum industry

WEAVE is the new wide-field spectroscopy facility for the prime focus of the William Herschel Telescope in La Palma, Spain. Its fibre positioner is essential for the accurate placement of the spectrograph's 960 fibre multiplex. We provide an overview of the recent maintenance, flexure modifications, and calibration measurements conducted at the observatory prior to the final top-end assembly. This work ensures that we have a complete understanding of the positioner's behaviour as it changes orientation during observations. All fibre systems have been inspected and repaired, and the tumbler structure contains new clamps to stiffen both the internal beam and the retractor support disk onto which the field plates attach. We present the updated metrology procedures and results that will be verified on-sky., Comment: 16 pages, 16 figures

The Hobby-Eberly Telescope (HET) Dark Energy Experiment (HETDEX) is undertaking a blind wide-field low-resolution spectroscopic survey of 540 square degrees of sky to identify and derive redshifts for a million Lyman-alpha emitting galaxies (LAEs) in the redshift range 1.9 < z < 3.5. The ultimate goal is to measure the expansion rate of the Universe at this epoch, to sharply constrain cosmological parameters and thus the nature of dark energy. A major multi-year wide field upgrade (WFU) of the HET was completed in 2016 that substantially increased the field of view to 22 arcminutes diameter and the pupil to 10 meters, by replacing the optical corrector, tracker, and prime focus instrument package and by developing a new telescope control system. The new, wide-field HET now feeds the Visible Integral-field Replicable Unit Spectrograph (VIRUS), a new low-resolution integral field spectrograph (LRS2), and the Habitable Zone Planet Finder (HPF), a precision near-infrared radial velocity spectrograph. VIRUS consists of 156 identical spectrographs fed by almost 35,000 fibers in 78 integral field units arrayed at the focus of the upgraded HET. VIRUS operates in a bandpass of 3500-5500 Angstroms with resolving power R~800. VIRUS is the first example of large scale replication applied to instrumentation in optical astronomy to achieve spectroscopic surveys of very large areas of sky. This paper presents technical details of the HET WFU and VIRUS, as flowed-down from the HETDEX science requirements, along with experience from commissioning this major telescope upgrade and the innovative instrumentation suite for HETDEX., 65 pages, 25 figures, published in the Astronomical Journal; replaced with final published version

WEAVE is a new wide-field multi-object spectroscopy (MOS) facility proposed for the prime focus of the 4.2m William Herschel Telescope. The facility comprises a new 2-degree field-of-view Prime Focus Corrector (PFC) with a 1000-multiplex fibre positioner, a small number of individually deployable integral field units, and a large single integral field unit (IFU). The IFUs and the MOS fibres can be used to feed a dual-beam spectrograph that will provide full coverage of the majority of the visible spectrum in a single exposure at a spectral resolution of ~5000 or modest wavelength coverage in both arms at a resolution ~20000. In order to compensate the field rotation, the Prime Focus Rotator (PFR) is assembled in between the WEAVE Fiber Positioner (system that positions the fibers in the focal plane) and with the Central Can (contains the Prime Focus corrector optics) on the William Herschel Telescope (WHT). The Prime Focus Rotator must provide a rotation degree of freedom for the Fibre Positioner with a high bending stiffness (causing a deflection smaller than 0.008° between interface flanges) adding the minimum mass possible to the system (less than 700kg). This is easily identified as the main design driver to be considered. The Prime Focus Rotator positions the Fibre Positioner to an accuracy of 5 arcsec when tracking and guides all the fibres and other power and control lines through a cable wrap, for which the available space is limited. IDOM proposal to comply with these coupled requirements consists of an optimized structural system with a slightly preloaded cross roller bearing providing the highest possible stiffness to weight ratio. The rotation is driven by means of a direct drive motor powered by a servo drive. For the Cable Wrap, a compact design based on a concept previously developed by IDOM for the Folded Cassegrain Sets the GTC was proposed.

The Drosophila adult midgut is a model epithelial tissue composed of a few major cell types with distinct regional identities. One of the limitations to its analysis is the lack of tools to manipulate gene expression based on these regional identities. To overcome this obstacle, we applied the intersectional split-GAL4 system to the adult midgut and report 653 driver combinations that label cells by region and cell type. We first identified 424 split-GAL4 drivers with midgut expression from over 7,300 drivers screened, and then evaluated the expression patterns of each of these 424 when paired with three reference drivers that report activity specifically in progenitor cells, enteroendocrine cells, or enterocytes. We also evaluated a subset of the drivers expressed in progenitor cells for expression in enteroblasts using another reference driver. We show that driver combinations can define novel cell populations by identifying a driver that marks a distinct subset of enteroendocrine cells expressing genes usually associated with progenitor cells. The regional cell type patterns associated with the entire set of driver combinations are documented in a freely available website, providing information for the design of thousands of additional driver combinations to experimentally manipulate small subsets of intestinal cells. In addition, we show that intestinal enhancers identified with the split-GAL4 system can confer equivalent expression patterns on other transgenic reporters. Altogether, the resource reported here will enable more precisely targeted gene expression for studying intestinal processes, epithelial cell functions, and diseases affecting self-renewing tissues.

The powerful combination of the cutting-edge multi-object spectrograph MOSAIC with the world largest telescope, the ELT, will allow us to probe deeper into the Universe than was possible. MOSAIC is an extremely efficient instrument in providing spectra for the numerous faint sources in the Universe, including the very first galaxies and sources of cosmic reionization. MOSAIC has a high multiplex in the NIR and in the VIS, in addition to multi-Integral Field Units (Multi-IFUs) in NIR. As such it is perfectly suited to carry out an inventory of dark matter (from rotation curves) and baryons in the cool-warm gas phases in galactic haloes at z=3-4. MOSAIC will enable detailed maps of the intergalactic medium at z=3, the evolutionary history of dwarf galaxies during a Hubble time, the chemistry directly measured from stars up to several Mpc. Finally, it will measure all faint features seen in cluster gravitational lenses or in streams surrounding nearby galactic halos, providing MOSAIC to be a powerful instrument with an extremely large space of discoveries. The preliminary design of MOSAIC is expected to begin next year, and its level of readiness is already high, given the instrumental studies made by the team., Comment: 8 pages, 4 Figures, Pre-edited version, to appear in the ESO Messenger No.182 - Quarter 1 2021 - Version identical to the Edited one

We report a tough, semicrystalline, ternary thiol–ene polymer system containing linear dithiols, cross-linking trithiols, and spiroacetal alkene units in the main chain backbone that is synthesized by “click” ultraviolet photopolymerization in a one-step, solvent-free process. We varied the cross-link density to tune crystallinity and microstructure; in turn, thermomechanical properties such as yield strength, glass transition temperature, failure strain, and stress–strain behavior could be modified and controlled. Thiol–enes containing 7.5 and 10 thiol mol % cross-linker resulted in networks that balanced crystallinity, elasticity, and cross-linking to maximize toughness. These materials demonstrate how the presence of spiro units throughout a polymer’s backbone creates semicrystalline networks of substantial toughness from traditionally weak chemistries such as thiol–enes. This system can be synthesized in a neat, one-step photopolymerization process; as such, it illustrates the power of spirochemistry ...

Thermoplastic polycarbonate urethanes (PCUs), have promise in many biomedical applications due to their low stiffness, favorable biocompatibility, and high strength. The long-term performance of PCU implants in load-bearing applications remains to be seen, and will depend in part on the material fatigue properties. Optimizing implants for success in fatigue-prone applications depends on a strong understanding of the relationship between material structure and fatigue performance, a surprisingly understudied area. In this study, we sought to develop relationships between PCU structure and mechanical properties, including fatigue, for three soft PCUs with systematically varied ratios of hard and soft segments. In addition, we compared injection molded controls to 3D printed (fused deposition modeling, FDM) varieties to examine the effects of such processing. Results indicate that increased hard segment content leads to increased stiffness, increased shear failure stress, and improvements in tensile fatigue from a stress-based standpoint despite relatively uniform tensile strength for the tested grades. Effects of hard segment content on tensile failure strain, and strain-based fatigue performance, were more complex and largely influenced by microphase organization and interaction. FDM samples matched or exceeded injection molded controls in terms of tensile failure stress and strain, compressive properties, shear strength, and tensile fatigue. The success of FDM samples is attributed in part to favorable printing parameters and the toughness of PCU which results in lower flaw sensitivity.

Network on Chip (NoC) is growing technology whereby multiprocessor state interconnect patterns are formed. NoC technology is adapted to support a variety of multiprocessor requirements. The existing designs do not support the growth requirements of user applications. Because of the complex routing connections, several problems exist about traffic congestion and Power consumption contributing to a network's low efficiency. Traffic Congestion, Power consumption, and latency are a significant concern in Network on Chip architectures because of various dynamic routing connections. The existing models do not consider all the above-mentioned factors and struggle to achieve higher performance. The previous methods do not trigger the circuits according to the traffic condition and maximum power consumption. For this, the proposed High-Speed Virtual Logic Network on Chip router architecture is utilized for controlling the traffic congestion and deadlock issues, reduce the latency by selecting the minimal interval paths. In this research work, an architecture containing a Virtual router is introduced which yields low power consumption resulting in improving the performance of a network by performing the routing in a diagonal direction along with the other directions. Also, the method selects an optimal path according to various conditions that neglect the unnecessary triggering of chips which reduces the power consumption. The proposed model considers the dynamic congestion and route available to perform routing with the least power consumption. By comparing both the architectures, VC Router outperformed 15% of low power consumption for the 8-bit system, 10% of low power consumption for the 16-bit system, and 22% of low power consumption for the 32-bit system.

The NS-Pten knockout (KO) mouse exhibits hyperactivity of the mammalian target of rapamycin (mTOR) and is a model of autism spectrum disorder (ASD). ASD presents with marked deficits in communication which can be elucidated by investigating their counterpart in mice, ultrasonic vocalizations (USVs). While USVs have been found to be altered in NS-Pten KO pups, no study has assessed whether this communication deficit persists into adulthood. In the present study, we investigate female urine-induced USVs, scent marking behavior, and open field activity in NS-Pten KO and wildtype (WT) adult male mice. Results showed that there was no difference in the quantity of vocalizations produced between groups, however, there were extensive alterations in the spectral properties of USVs. KO mice emitted vocalizations of a lower peak frequency, shorter duration, and higher peak amplitude compared to WT mice. KO animals also emitted a significantly different distribution of call-types relative to controls, displaying increased complex and short calls, but fewer upward, chevron, frequency steps, and composite calls. No significant differences between groups were observed for scent marking behavior and there was no difference between groups in the amount of time spent near the female urine. Overall, this study demonstrated that mTOR hyperactivity contributes to communication deficits in adult mice.