CHEMICAL COMPLEXITY IN THE SHOCKED OUTFLOW L1157-B REVEALED BY CARMA

We present results from a targeted chemical search toward the prototypical shocked outflow L1157. L1157-B0, -B1, and -B2 are shocked regions within the outflow from the Class 0 low-mass protostar L1157-mm. We have mapped a variety of molecular tracers in the region with typical spatial resolutions of $sim$ 3$^{primeprime}$ using CARMA, and find differences in the chemical makeups between shocked regions within the same precursor outflow material. We present observations of chem{CH_3OH}, chem{HCO^+}, HCN, and the first maps of HNCO in the source. We will examine the utility of HNCO as a sensitive tracer of the shocks in this source, and finally, we will discuss what insights we can gain into the chemical evolution, and evolutionary time scales, that have given rise to the differentiation we see between the shocks

Butterflies and Moths of Peru

The Order Lepidoptera is one of the most widely recognized orders in the world, it includes butterflies and moths and composes 10% of all described species on the planet. Butterflies and moths have an important role as pollinators, food sources and biological indicators of ecosystem health. Peru is a megadiverse country with the most butterfly species in the world, making it an excellent place to study Lepidoptera species richness and moth diversity. Diversity is indicative of ecosystem health, as these species play a vital role in the ecosystem as pollinators and a food source for other species. Traditionally, species richness of a geographic location would be collected from literature or museum inventory, however, citizen science apps like iNaturalist make species identification simpler and easily accessible. Images of moths, butterflies, and caterpillars in the Madre de Dios region were uploaded to iNaturalist and a list of species was compiled

Proposal of \u3cem\u3eVibrionimonas magnilacihabitans\u3c/em\u3e gen. nov., sp. nov., a Curved Gram Negative Bacterium Isolated From Lake Michigan Water

A mesophilic bacterium appearing as curved rod-shaped cells was isolated from Lake Michigan water. It exhibited highest similarities with Sediminibacterium ginsengisoli DCY13T (94.4 %); Sediminibacterium salmoneum NJ-44T (93.6 %) and Hydrotalea flava CCUG 51397 T (93.1 %) while similarities with other recognized species were sym-homospermidine was the primary polyamine. The major cellular fatty acids were iso-C15 : 1G, iso-C15 : 0, iso-C16 : 0 3-OH and iso-C17 : 0 3-OH, with moderate amounts of iso-C16 : 0. The presence of glycolipids differentiated the novel strains from related genera. The DNA mol% G+C content of the type strain MU-2T was 45.2. Results for other phenotypic and molecular analyses indicated that strain MU-2T is a representative of a novel genus and species for which the name Vibrionimonas magnilacihabitans is proposed. The type strain is MU-2T ( = NRRL B-59231 = DSM 22423)

Nascar Restrictor Plate Exhaust Manifold Design Strategies

This paper presents the results of a study on exhaust manifold design for a NASCAR Restrictor plate internal combustion engine. A computer simulation model was developed using Ricardo WAVE software. WAVE is a computer-aided engineering code developed by Ricardo to analyze the dynamics of pressure waves, mass flows and energy losses in ducts, plenums and the intake and exhaust manifolds of various systems and machines. [1] The model was validated against experimental data from a current NASCAR Winston Cup restrictor plate motor. The parameters studied have been exhaust manifold diameters and lengths. A response surface analysis of the simulation output followed. The analysis of results shows the design parameters of the existing exhaust manifold are not optimized. The findings from these studies are used to derive exhaust system design guidelines which define optimum exhaust system geometry to maximize average Brake Horsepower over a given powerband for a restrictor plate NASCAR engine

Technical feasibility and clinical success of direct "free hand" EUS-guided gastroenterostomy in patients with gastric outlet obstruction

Background and study aims  Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) with lumen-apposing metal stents (LAMS) appears to be a promising intervention in management of gastroduodenal out obstruction (GOO), particularly for patients for whom surgery is high risk or in a palliative setting. This study aimed to evaluate the technical feasibility, procedure-associated adverse events (AEs), and clinical outcome of direct "free hand" EUS-GE. Patients and methods  This retrospective two-center study included patients who underwent direct "free hand" EUS-GE (April 2017 to March 2021) investigating technical success (correctly placed LAMS), clinical outcome (successful oral nutrition), and management of procedure-associated AEs. "Free hand" was defined as the use of the electrocautery enhanced stent delivery system alone without additional guidewire-assistance for EUS-GE creation. Results  Forty-five patients (58 % women/42 % men; mean age 65 years) with malignant (n = 39), benign (n = 4) or unclear (n = 2) GOO underwent direct "free hand" EUS-GE. The technical success rate was 98 % (44/45). Of the patients, 95% (42/44) had less vomiting and increased ability to tolerate oral food intake after the intervention. In one patient, a second EUS-GE was necessary to achieve sufficient clinical improvement. Procedure-associated AEs were observed in 24 % (11/45) of cases including stent misplacement (n = 7), leakage (n = 1), development of a gastrojejunocolic fistula (n = 1), and bleeding (n = 2), which could be all managed endoscopically. Conclusions  Direct EUS-GE has a favorable risk-benefit profile for patients with GOO, showing high technical success rates, manageable AEs, and rapid symptom relief

CSO and CARMA Observations of L1157. I. A Deep Search for Hydroxylamine (NH2_2OH)

A deep search for the potential glycine precursor hydroxylamine (NH$_2$OH) using the Caltech Submillimeter Observatory (CSO) at $\lambda = 1.3$ mm and the Combined Array for Research in Millimeter-wave Astronomy (CARMA) at $\lambda = 3$ mm is presented toward the molecular outflow L1157, targeting the B1 and B2 shocked regions. We report non-detections of NH$_2$OH in both sources. We a perform non-LTE analysis of CH$_3$OH observed in our CSO spectra to derive kinetic temperatures and densities in the shocked regions. Using these parameters, we derive upper limit column densities of NH$_2$OH of $\leq1.4 \times 10^{13}$~cm$^{-2}$ and $\leq1.5 \times 10^{13}$~cm$^{-2}$ toward the B1 and B2 shocks, respectively, and upper limit relative abundances of $N_{NH_2OH}/N_{H_2} \leq1.4 \times 10^{-8}$ and $\leq1.5 \times 10^{-8}$, respectively.Comment: Accepted in the Astrophysical Journa

CSO and CARMA Observations of L1157. II. Chemical Complexity in the Shocked Outflow

L1157, a molecular dark cloud with an embedded Class 0 protostar possessing a bipolar outflow, is an excellent source for studying shock chemistry, including grain-surface chemistry prior to shocks, and post-shock, gas-phase processing. The L1157-B1 and B2 positions experienced shocks at an estimated ~2000 and 4000 years ago, respectively. Prior to these shock events, temperatures were too low for most complex organic molecules to undergo thermal desorption. Thus, the shocks should have liberated these molecules from the ice grain-surfaces en masse, evidenced by prior observations of SiO and multiple grain mantle species commonly associated with shocks. Grain species, such as OCS, CH3OH, and HNCO, all peak at different positions relative to species that are preferably formed in higher velocity shocks or repeatedly-shocked material, such as SiO and HCN. Here, we present high spatial resolution (~3") maps of CH3OH, HNCO, HCN, and HCO+ in the southern portion of the outflow containing B1 and B2, as observed with CARMA. The HNCO maps are the first interferometric observations of this species in L1157. The maps show distinct differences in the chemistry within the various shocked regions in L1157B. This is further supported through constraints of the molecular abundances using the non-LTE code RADEX (Van der Tak et al. 2007). We find the east/west chemical differentiation in C2 may be explained by the contrast of the shock's interaction with either cold, pristine material or warm, previously-shocked gas, as seen in enhanced HCN abundances. In addition, the enhancement of the HNCO abundance toward the the older shock, B2, suggests the importance of high-temperature O-chemistry in shocked regions.Comment: Accepted for publication in the Astrophysical Journa