In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

Q: A new porcine coronavirus SADS-CoV was recently identified from suckling piglets 20 with severe diarrhea in southern China and its genome sequence is most identical (~95% 21 identity) to that of bat -coronavirus HKU2. It again indicates bats are the natural 22 reservoir of many coronaviruses that have great potential for cross-species transmission 23 to animals and humans by recombination and/or mutation. Here we report the cryo-EM 24 structures of HKU2 and SADS-CoV spike glycoprotein trimers at 2.38 A and 2.83 A 25 resolution, respectively. HKU2 and SADS-CoV spikes exhibit very high structural 26 similarity, with subtle differences mainly distributed in the NTD and CTD of the S1 27 subunit responsible for cell attachment and receptor binding. We systematically 28 analyzed and compared the NTD, CTD, SD1 and SD2 domains of the S1 subunit and 29 the S2 subunit of HKU2 spike with those of -, -, -, and -coronavirus spikes. The 30 results show that the NTD and CTD of HKU2/SADS-CoV are probably the most 31 ancestral in the evolution of spike. Although the S2 subunit mediating membrane fusion 32 is highly conserved, the connecting region after fusion peptide in HKU2/SADS-CoV 33 S2 subunit also adopts a conformation distinct from other coronaviruses. These results 34 structurally demonstrate a close evolutionary relationship between HKU2 /SADS-CoV 35 and -coronavirus spikes and provide new insights into the evolution and cross-species 36 transmission of coronaviruses. : bioRxiv preprint 39 Coronaviruses, categorized into the order Nidovirales family Coronaviridae and 40 subfamily Coronavirinae, are a large group of viral pathogens with a wide host range 1 . 41 Their infections in humans, other mammals and birds can cause respiratory, hepatic, 42 enteric and neurological diseases with varying severity 2 . The severe acute respiratory 43 syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus 44 (MERS-CoV) have posed severe threats to human health in the 21 st century 1,3 . In the 45 meantime, coronaviruses infecting domestic animals also bring substantial economic 46 losses 4 . For example, the swine acute diarrhea syndrome coronavirus (SADS-CoV) 47 (also known as SeACoV and PEAV) isolated in 2017 caused outbreaks of severe watery 48 diarrhea of suckling piglets with a mortality up to 90% in several commercial pig farms 49 in Guangdong Province of China 5-10 . SADS-CoV is an -coronavirus and other 50 representative members in the -genus are porcine epidemic diarrhea virus 51 (PEDV), porcine transmissible gastroenteritis coronavirus (TGEV), porcine respiratory 52 coronavirus (PRCV), human NL63 and 229E coronaviruses (HCoV-NL63 and HCoV-53 229E) 1 . Representative members in other three genera include mouse hepatitis 54 coronavirus (MHV), bovine coronavirus (BCoV), SARS-CoV, MERS-CoV, HCoV-55 OC43 and HCoV-HKU1 in the -genus, avian infectious bronchitis virus (IBV) in the 56 -genus and porcine deltacoronavirus (PdCoV) in the -genus 1 . 57 Cross-species transmission promoted by genetic recombination and/or mutations 58 underlies the host range expansion of coronaviruses 3,11-13 . Bats are the natural reservoir 59 of more than 30 different -and -coronaviruses that have great potential for 60 interspecies transmission by recombination and/or mutation 12,14-16 . Data on genetic 61 evolution, receptor binding and pathogenesis have demonstrated that human SARS-62 CoV and MERS-CoV most likely originate from bats 1 . Palm civets and dromedary 63 camels are the intermediate hosts of SARS-CoV and MERS-CoV from bats to humans 1 , 64 respectively. The newly identified porcine SADS-CoV isolates are also found to share 65 ~95% sequence identity with Rhinolophus bat coronavirus HKU2, and this further 66 stressed the severe results of coronavirus spillover from bats to domestic animals 5-10 .

A: Cryo-EM structures of HKU2 and SADS-CoV spike 1 glycoproteins and insights into coronavirus evolution 2 3 4
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Q: One word can be used to best describe the theme of each day that has transpired since the onset of the COVID-19 pandemic: uncertainty. Urologic surgical residents around the nation are faced with the unknown when they walk through the doors of the hospital each day. While experience has taught us navigational strategies to handle these circumstances, the COVID-19 pandemic has undoubtedly brought new meaning to this concept. Priorities have quickly transitioned from closely following our previously developed academic curriculum and enhancing our surgical skills, to limiting physician-patient encounters and ensuring the safety and health of our team. Normalcy within our professional and personal lives is completely lost. Yet, as health care providers, we must and will forge on. We review the techniques and guidelines that our institution has implemented in order to allow us to do just that. We believe that our leadership, both at an enterprise and program level, has taken the necessary and early measures to prepare our residency cohort for the uncertain future and challenges posed by COVID-19. This plan emphasizes social and professional distancing, allows residents and faculty to stay current on academic topics, and provides reasonable opportunities for personal wellness, all while emphasizing safety and rationalization. Most importantly, however, we have continued to provide our patients with exceptional urologic care at 2 adult hospitals and 1 children's hospital in the Greater Akron, Ohio area. While we understand each residency program has a unique curriculum with a different number of residents that cover a range of different hospitals, we hope to provide insight into our personal experience. We believe that this method of organization allows a residency program to continue to grow professionally, socially, academically, and personally during the uncertainty that is COVID-19. This framework could serve as an immediate action plan for future pandemics and natural disasters, especially for residency programs that cover multiple hospitals and health care settings.

A: Editorial Cleveland Clinic Akron General Urology Residency Program's COVID-19 Experience
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Q: The observations that Lymphopenia is common in severe acute respiratory syndrome (SARS) patients and that peripheral blood mononuclear cell (PBMC) could be infected by SARS-CoV indicate that PBMC could be useful in identifying the gene expression profile in convalescent patients and tracing the host response to SARS-CoV infection. In this study, the altered genes expressions in the PBMC of convalescent SARS patients were investigated with suppression subtractive hybridization (SSH). We found that genes encoded by mitochondrial DNA (mtDNA) were obviously upregulated, while mitochondria were now found to be closely connected with antiviral immunity. The identification of a viral gene, M, in SSH cDNA library shows the long-term existence of SARS-CoV in vivo. In addition, some oxidative stress sensitive genes, heat shock proteins, transcription factors, and cytokines showed remarkable elevation. Thin-section electron microscope shows increased lysosome-like granule and mitochondria in PBMC of patients. These results provide important intracellular clue for tracing host response to SARS-CoV infection and suggest a role of mitochondria in that process.

A:
Upregulation of Mitochondrial Gene Expression in PBMC from Convalescent SARS Patients
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