Publications by authors named "Irene Zhang"

Microorganisms in marine oxygen minimum zones (OMZs) drive globally impactful biogeochemical processes. One such process is multistep denitrification (NO→NO→NO→NO→N), which dominates OMZ bioavailable nitrogen (N) loss and nitrous oxide (NO) production. Denitrification-derived N loss is typically measured and modeled as a single step, but observations reveal that most denitrifiers in OMZs contain subsets ("modules") of the complete pathway.

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The development of perfusable and multiscale vascular networks remains one of the largest challenges in tissue engineering. As such, there is a need for the creation of customizable and facile methods to produce robustly vascularized constructs. In this study, secondarily crosslinkable (clickable) poly(ethylene glycol)-norbornene (PEGNB) microbeads were produced and evaluated for their ability to sequentially support suspension bioprinting and microvascular self-assembly towards the aim of engineering hierarchical vasculature.

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Anammox bacteria inhabiting oxygen-deficient zones (ODZs) are a major functional group mediating fixed nitrogen loss in the global ocean. However, many basic questions regarding the diversity, broad metabolisms, origin, and adaptive mechanisms of ODZ anammox bacteria remain unaddressed. Here we report two novel metagenome-assembled genomes of anammox bacteria affiliated with the genus, which represent most, if not all, of the anammox bacteria in the global ODZs.

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Introduction: Even with effective vaccines, patients with CKD have a higher risk of hospitalization and death subsequent to COVID-19 infection than those without CKD. Molnupiravir and nirmatrelvir-ritonavir have been approved for emergency use, but their effectiveness for the CKD population is still unknown. This study was conducted to determine the effectiveness of these drugs in reducing mortality and severe COVID-19 in the CKD population.

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Unlabelled: Archaea belonging to the DPANN (Diapherotrites, Parvarchaeota, Aenigmarchaeota, Nanoarchaeota, and Nanohaloarchaeota) superphylum have been found in an expanding number of environments and perform a variety of biogeochemical roles, including contributing to carbon, sulfur, and nitrogen cycling. Generally characterized by ultrasmall cell sizes and reduced genomes, DPANN archaea may form mutualistic, commensal, or parasitic interactions with various archaeal and bacterial hosts, influencing the ecology and functioning of microbial communities. While DPANN archaea reportedly comprise a sizeable fraction of the archaeal community within marine oxygen-deficient zone (ODZ) water columns, little is known about their metabolic capabilities in these ecosystems.

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Archaea belonging to the DPANN superphylum have been found within an expanding number of environments and perform a variety of biogeochemical roles, including contributing to carbon, sulfur, and nitrogen cycling. Generally characterized by ultrasmall cell sizes and reduced genomes, DPANN archaea may form mutualistic, commensal, or parasitic interactions with various archaeal and bacterial hosts, influencing the ecology and functioning of microbial communities. While DPANN archaea reportedly comprise 15-26% of the archaeal community within marine oxygen deficient zone (ODZ) water columns, little is known about their metabolic capabilities in these ecosystems.

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Parental depression is a risk factor for children's cognitive and psychological development. Literature has found reciprocal relations between parental depression and child psychopathology and effects of parental depression on children's cognition. The present study is the first to examine reciprocity among parental depression and child cognition, and pathways to child psychopathology.

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Background: Diffusing alpha-emitters Radiation Therapy ("DaRT") is a promising new modality for the treatment of solid tumors. Interstitial sources containing Ra are inserted into the tumor, producing alpha particles via the decay of Ra and its daughters. The alpha particles are able to produce a "kill region" of several mm due to the diffusion of the alpha-emitting atoms.

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Oxygen deficient zones (ODZs) account for about 30% of total oceanic fixed nitrogen loss via processes including denitrification, a microbially mediated pathway proceeding stepwise from NO to N. This process may be performed entirely by complete denitrifiers capable of all four enzymatic steps, but many organisms possess only partial denitrification pathways, either producing or consuming key intermediates such as the greenhouse gas NO. Metagenomics and marker gene surveys have revealed a diversity of denitrification genes within ODZs, but whether these genes co-occur within complete or partial denitrifiers and the identities of denitrifying taxa remain open questions.

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Particulate organic carbon settling through the marine water column is a key process that regulates the global climate by sequestering atmospheric carbon. The initial colonization of marine particles by heterotrophic bacteria represents the first step in recycling this carbon back to inorganic constituents-setting the magnitude of vertical carbon transport to the abyss. Here, we demonstrate experimentally using millifluidic devices that, although bacterial motility is essential for effective colonization of a particle leaking organic nutrients into the water column, chemotaxis specifically benefits at intermediate and higher settling velocities to navigate the particle boundary layer during the brief window of opportunity provided by a passing particle.

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Sinking marine particles drive the biological pump that naturally sequesters carbon from the atmosphere. Despite their small size, the compartmentalized nature of particles promotes intense localized metabolic activity by their bacterial colonizers. Yet the mechanisms promoting the onset of denitrification, a metabolism that arises once oxygen is limiting, remain to be established.

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Importance: A patient's belief in the likely success of a treatment may influence outcomes, but this has been understudied in surgical trials.

Objective: To examine the association between patients' baseline beliefs about the likelihood of treatment success with outcomes of antibiotics for appendicitis in the Comparison of Outcomes of Antibiotic Drugs and Appendectomy (CODA) trial.

Design, Setting, And Participants: This was a secondary analysis of the CODA randomized clinical trial.

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Background: Patients with injury may be at high risk of long-term opioid use due to the specific features of injury (e.g., injury severity), as well as patient, treatment, and provider characteristics that may influence their injury-related pain management.

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Background: Restrictive state and payer policies may be effective in reducing opioid prescribing by surgeons, but their impact has not been well studied. In 2017, Washington Medicaid implemented an opiod prescribing limit of 42 pills, prompting a large regional safety-net hospital to implement a decision support intervention in response. We aimed to evaluate the effects on surgeons' prescribing.

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Introduction: Dietary interventions are increasingly being proposed as alternatives to surgery for common gastrointestinal conditions. Integrating aspects of cognitive psychology (e.g.

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Background: Judicious opioid prescribing and patient counseling, including in the postoperative context, are important efforts to address the U.S. opioid crisis.

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Chronic type 2 (T2) inflammatory diseases of the respiratory tract are characterized by mucus overproduction and disordered mucociliary function, which are largely attributed to the effects of IL-13 on common epithelial cell types (mucus secretory and ciliated cells). The role of rare cells in airway T2 inflammation is less clear, though tuft cells have been shown to be critical in the initiation of T2 immunity in the intestine. Using bulk and single-cell RNA sequencing of airway epithelium and mouse modeling, we found that IL-13 expanded and programmed airway tuft cells toward eicosanoid metabolism and that tuft cell deficiency led to a reduction in airway prostaglandin E2 (PGE2) concentration.

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Controlled transport of biomolecules across lipid bilayer membranes is of profound significance in biological processes. In cells, cargo exchange is mediated by dedicated channels that respond to triggers, undergo a nanomechanical change to reversibly open, and thus regulate cargo flux. Replicating these processes with simple yet programmable chemical means is of fundamental scientific interest.

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Denitrifying microbes sequentially reduce nitrate (NO ) to nitrite (NO ), NO, NO, and N through enzymes encoded by , , , and . Some denitrifiers maintain the whole four-gene pathway, but others possess partial pathways. Partial denitrifiers may evolve through metabolic specialization whereas complete denitrifiers may adapt toward greater metabolic flexibility in nitrogen oxide (NO ) utilization.

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Health and emotions are inexorably connected. Yet there is still little emphasis on emotions in many clinical decision-making tools and interventions. Instead, existing solutions have tended to target cognition - how people comprehend and act on information about health and disease.

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