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The COVID-19 pandemic substantially impacted many aspects of regular life including financial markets. The increased media attention and slowdown associated with the pandemic provide the opportunity to explore how both institutional and retail traders react to an attention-grabbing event. We examine how the market responded to a unique presidential press conference including CEOs of eight publicly-listed U.S. companies addressing the U.S.’s response to the pandemic. Using the press conference on March 13, 2020, we examine the effect on the trading volatility and returns for each of the eight companies represented. We find positive abnormal returns for the companies participating in the press conference. Using the Robintrack data aggregated from the Robinhood retail trading platform and intraday TAQ data, we see that both retail and institutional trading volume increased on the press conference day. However, the increase in retail trading approximately doubled the increase in institutional trading. For the two companies with the lowest Robinhood user ownership prior to the press conference, ownership more than doubled within an hour of the press conference. Panel VAR analysis including control firms shows the press conference resulted in significant intraday returns, volume, and buy-order imbalances in participating firms’ stock.

The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, and even lasers as weapons (e.g., Airborne Laser). Lasers in the support of telecommunications is also not new. The use of laser light in fiber optics has shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform the U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers, rather than traditional radio frequency sources for satellite uplink and downlink signal carriers, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, and large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploit (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt.

Purpose The purpose of this paper is to examine the impact hosting the Super Bowl has on audit completion and financial reporting timeliness for companies headquartered in Super Bowl hosting cities. Design/methodology/approach Using 16 years of financial reporting data, this study uses the Super Bowl and related activities, combined with required filings during “busy season,” as a natural experiment to examine how audit firms navigate short-term, exogenously imposed but anticipated, audit team capacity constraints. Findings Companies headquartered in a city hosting the Super Bowl, during busy season, have longer audit report lags (by approximately three days, in comparison to non-hosting busy season audits) and less timely securities and exchange commission (SEC) (10-K) filings. The authors find no evidence that Super Bowl hosting affects audit fees or earnings announcement timeliness. Practical implications When confronted with anticipated capacity shocks, audit firms take longer to complete the audit, absorbing the financial costs of the delay and maintaining audit quality, resulting in less timely financial reporting. Originality/value This study demonstrates the costs of Super Bowl-related inefficiencies and contributes to our understanding of how auditors navigate capacity shocks. This study provides evidence that auditors can effectively manage business risk and continue to facilitate providing timely and accurate information to financial statement users in the face of a capacity shock.

The root nodule symbiosis of plants with nitrogen-fixing bacteria impacts global nitrogen cycles and food production but is restricted to a subset of genera within a single clade of flowering plants. To explore the genetic basis for this scattered occurrence, we sequenced the genomes of ten plant species covering the diversity of nodule morphotypes, bacterial symbionts and infection strategies. In a genome-wide comparative analysis of a total of 37 plant species, we discovered signatures of multiple independent loss-of-function events in the indispensable symbiotic regulator NODULE INCEPTION (NIN) in ten out of 13 genomes of non-nodulating species within this clade. The discovery that multiple independent losses shaped the present day distribution of nitrogen-fixing root nodule symbiosis in plants reveals a phylogenetically wider distribution in evolutionary history and a so far underestimated selection pressure against this symbiosis.

Purpose The purpose of this paper is to examine the impact firm proximity to financial centers has on announcement returns and time to deal completion for mergers and acquisitions. Design/methodology/approach Using a data set of merger and acquisition activity from 1986 to 2014, target and acquiring firms are classified as rural or urban based on their geographic proximity to major financial centers. The impact of this proximity on short-term acquisition announcement returns and on the amount of time required to complete the transaction are tested. Findings Markets react more favorably to the acquisition of firms headquartered in a rural area, likely due to increased information advantage on the part of the acquiring firm. Furthermore, the acquisition of a rural firm requires greater time to completion. Practical implications Acquiring firms may be able to use information asymmetry to their advantage when acquiring firms located in a more rural setting with higher levels of information asymmetry. However, this requires the acquiring firm to generate an informational advantage and will also require a greater time commitment on average to complete the deal. Originality/value While prior literature has demonstrated that the distance between target and acquirer can affect acquisition returns and time to deal completion, this study adds to the literature by demonstrating that the geographic location of the target firm relative to major financial hubs can have a unique effect on mergers and acquisitions as well.

Genomic traces of symbiosis loss A symbiosis between certain bacteria and their plant hosts delivers fixed nitrogen to the plants. Griesmann et al. sequenced several plant genomes to analyze why nitrogen-fixing symbiosis is irregularly scattered through the evolutionary tree (see the Perspective by Nagy). Various genomes carried traces of lost pathways that could have supported nitrogen-fixing symbiosis. It seems that this symbiosis, which relies on multiple pathways and complex interorganismal signaling, is susceptible to selection and prone to being lost over evolutionary time. Science , this issue p. eaat1743 ; see also p. 125

Burkholderia sensu lato is a large and complex group, containing pathogenic, phytopathogenic, symbiotic and non-symbiotic strains from a very wide range of environmental (soil, water, plants, fungi) and clinical (animal, human) habitats. Its taxonomy has been evaluated several times through the analysis of 16S rRNA sequences, concantenated 4–7 housekeeping gene sequences, and lately by genome sequences. Currently, the division of this group into Burkholderia, Caballeronia, Paraburkholderia, and Robbsia is strongly supported by genome analysis. These new genera broadly correspond to the various habitats/lifestyles of Burkholderia s.l., e.g., all the plant beneficial and environmental (PBE) strains are included in Paraburkholderia (which also includes all the N2-fixing legume symbionts) and Caballeronia, while most of the human and animal pathogens are retained in Burkholderia sensu stricto. However, none of these genera can accommodate two important groups of species. One of these includes the closely related Paraburkholderia rhizoxinica and Paraburkholderia endofungorum, which are both symbionts of the fungal phytopathogen Rhizopus microsporus. The second group comprises the Mimosa-nodulating bacterium Paraburkholderia symbiotica, the phytopathogen Paraburkholderia caryophylli, and the soil bacteria Burkholderia dabaoshanensis and Paraburkholderia soli. In order to clarify their positions within Burkholderia sensu lato, a phylogenomic approach based on a maximum likelihood analysis of conserved genes from more than 100 Burkholderia sensu lato species was carried out. Additionally, the average nucleotide identity (ANI) and amino acid identity (AAI) were calculated. The data strongly supported the existence of two distinct and unique clades, which in fact sustain the description of two novel genera Mycetohabitans gen. nov. and Trinickia gen. nov. The newly proposed combinations are Mycetohabitans endofungorum comb. nov., Mycetohabitansrhizoxinica comb. nov., Trinickia caryophylli comb. nov., Trinickiadabaoshanensis comb. nov., Trinickia soli comb. nov., and Trinickiasymbiotica comb. nov. Given that the division between the genera that comprise Burkholderia s.l. in terms of their lifestyles is often complex, differential characteristics of the genomes of these new combinations were investigated. In addition, two important lifestyle-determining traits—diazotrophy and/or symbiotic nodulation, and pathogenesis—were analyzed in depth i.e., the phylogenetic positions of nitrogen fixation and nodulation genes in Trinickia via-à-vis other Burkholderiaceae were determined, and the possibility of pathogenesis in Mycetohabitans and Trinickia was tested by performing infection experiments on plants and the nematode Caenorhabditis elegans. It is concluded that (1) T. symbiotica nif and nod genes fit within the wider Mimosa-nodulating Burkholderiaceae but appear in separate clades and that T. caryophyllinif genes are basal to the free-living Burkholderia s.l. strains, while with regard to pathogenesis (2) none of the Mycetohabitans and Trinickia strains tested are likely to be pathogenic, except for the known phytopathogen T. caryophylli.

he first overview of US NC3 since the 1980s, Nuclear Command, Control, and Communications explores the current NC3 system and its vital role in ensuring effective deterrence, contemporary challenges posed by cyber threats, new weapons technologies, and the need to modernize the United States' Cold War-era system of systems.

Microorganisms interact frequently with each other and with higher organisms. This contact and communication takes place at the molecular level. Microbial interactions with eukaryotes can be pathogenic or mutualistic. One of the best-studied symbioses is the complex interaction between nitrogen-fixing soil bacteria, termed rhizobia, and legumes. This symbiosis culminates in the elaboration of a new organ, the root nodule. Many of the molecular signals exchanged between the host plant and the invading rhizobia have been deduced, but there is still much that remains to be discovered. The molecular determinant of host range at the genus level of the plant host has been determined to be lipochitooligomers called Nod factors. The molecular determinants of host range at the species and cultivar level are less well-defined. Part of my work has been to identify and characterize accessory plasmids that disrupt the normal progression of symbiosis between legumes of the genus Medicago and their rhizobial symbiont, Sinorhizobium meliloti . A cre–loxP-based system capable of making large, defined deletions was developed for the analysis of these plasmids. This system is also being employed to cure the laboratory strain, S. meliloti Rm1021 of its two megaplasmids—a loss of nearly half of its genome. I have also done work to determine whether locally-collected sinorhizobia are native, invasive, or native with symbiosis genes acquired horizontally from invasive sinorhizobia. Finally, I have studied Sinorhizobium meliloti as a host by identifying an outer membrane porin that several bacteriophages use to adsorb to the S. meliloti cell surface.