University of California, Santa Cruz
  • Santa Cruz, California, United States
Recent publications
Introduction This case report presents a unique acute dystonic reaction (ADR) induced by metoclopramide in a 6-year-old male patient with pertussis-associated vomiting. The rarity of such a reaction in pediatric patients underscores the significance of this case in contributing to the scientific literature. This report highlights the need for heightened awareness of the potential adverse effects of medications commonly used in pediatrics and emphasizes the importance of tailored interventions for this population. Main symptoms and important clinical findings Following the administration of metoclopramide for vomiting associated with pertussis cough, the patient exhibited distressing symptoms, including torticollis, facial grimacing, and tongue protrusion. These involuntary movements were promptly recognized, leading to the suspicion of an ADR. The clinical findings underscore the importance of vigilant monitoring for extrapyramidal symptoms following medication administration, especially in children. The main diagnoses, therapeutic interventions, and outcomes The primary diagnosis of ADR induced by metoclopramide was confirmed, prompting the cessation of the medication and the initiation of anticholinergic therapy with benztropine. This intervention rapidly resolved the patient’s symptoms, highlighting the importance of tailored and swift therapeutic strategies. The outcome demonstrated the efficacy of timely intervention in managing ADR in pediatric patients. Conclusion The main takeaway lesson from this case lies in the critical need for healthcare practitioners to remain vigilant for potential adverse reactions in pediatric patients, even when prescribing commonly used medications. The successful management of this case underscores the importance of prompt recognition, appropriate interventions, and continuous monitoring. Ultimately, this case contributes to the scientific literature by highlighting the unique manifestation of ADR in a pediatric patient, reinforcing the significance of individualized patient care and medication safety.
Introduction This case report highlights a distinctive presentation of cardiovascular sequelae arising from hyperthyroidism, shedding light on a rarely observed condition within the medical literature. The unique aspects of this case contribute valuable insights to our understanding of the intricate relationship between thyroid dysfunction and cardiac complications. Clinical presentation The patient exhibited a constellation of symptoms, including palpitations, weight loss, and anxiety, indicative of hyperthyroidism. Notably, a thorough clinical examination revealed critical cardiovascular findings, such as elevated heart rate, arrhythmias, and signs of heart failure, underscoring the significant cardiac implications associated with this disorder. Diagnosis and interventions Following a comprehensive diagnostic process, the patient was diagnosed with thyrotoxic cardiomyopathy, a rare manifestation of hyperthyroidism characterized by cardiac muscle dysfunction. Therapeutic interventions encompassed a multidisciplinary approach involving antithyroid medications, beta-blockers, and supportive heart failure management. The intricate connection between thyroid function and cardiac performance necessitated tailored treatment strategies. Outcomes A notable improvement in the patient’s clinical status was observed throughout treatment. Reduction in heart rate, resolution of arrhythmias, and amelioration of heart failure symptoms collectively underscored the efficacy of the chosen interventions. This case report emphasizes the importance of prompt and accurate diagnosis and a comprehensive treatment regimen in achieving positive clinical outcomes in patients with thyrotoxic cardiomyopathy. Conclusion This case is a poignant reminder of the interplay between endocrine and cardiovascular systems. The unique presentation of thyrotoxic cardiomyopathy in the context of hyperthyroidism expands our knowledge of potential cardiovascular sequelae. Clinicians are urged to consider such intricate connections and remain vigilant for atypical cardiac manifestations in patients with thyroid dysfunction. Timely intervention and tailored management strategies are paramount in mitigating the impact of these rare yet clinically significant conditions.
Connective tissue disorders, including Marfan syndrome (MS) and Ehlers-Danlos syndrome (EDS), are characterized by genetic mutations affecting connective tissue structural integrity. These disorders significantly elevate the risk of aortic dissection, a life-threatening condition. This comprehensive review delves into the intricate interplay between connective tissue disorders and aortic dissection, shedding light on the clinical features, pathophysiology, genetic underpinnings, diagnostic approaches, clinical management, associated comorbidities, and prognosis, mainly focusing on MS and EDS, while also exploring rare connective tissue disorders and forms of cutis laxa contributing to aortic pathology. Abbreviations: ECM = extracellular matrix, EDS = Ehlers-Danlos syndrome, FBN1 = Fibrillin-1, MS = Marfan syndrome, PT = prothrombin time, TGFβ = transforming growth factor-beta.
Background: The South African national cause of death validation (NCODV 2017/18) project collected a national sample of verbal autopsies (VA) with cause of death (COD) assignment by physician-coded VA (PCVA) and computer-coded VA (CCVA). Objective: The performance of three CCVA algorithms (InterVA-5, InSilicoVA and Tariff 2.0) in assigning a COD was compared with PCVA (reference standard). Methods: Seven performance metrics assessed individual and population level agreement of COD assignment by age, sex and place of death subgroups. Positive predictive value (PPV), sensitivity, overall agreement, kappa, and chance corrected concordance (CCC) assessed individual level agreement. Cause-specific mortality fraction (CSMF) accuracy and Spearman's rank correlation assessed population level agreement. Results: A total of 5386 VA records were analysed. PCVA and CCVAs all identified HIV/AIDS as the leading COD. CCVA PPV and sensitivity, based on confidence intervals, were comparable except for HIV/AIDS, TB, maternal, diabetes mellitus, other cancers, and some injuries. CCVAs performed well for identifying perinatal deaths, road traffic accidents, suicide and homicide but poorly for pneumonia, other infectious diseases and renal failure. Overall agreement between CCVAs and PCVA for the top single cause (48.2-51.6) indicated comparable weak agreement between methods. Overall agreement, for the top three causes showed moderate agreement for InterVA (70.9) and InSilicoVA (73.8). Agreement based on kappa (-0.05-0.49)and CCC (0.06-0.43) was weak to none for all algorithms and groups. CCVAs had moderate to strong agreement for CSMF accuracy, with InterVA-5 highest for neonates (0.90), Tariff 2.0 highest for adults (0.89) and males (0.84), and InSilicoVA highest for females (0.88), elders (0.83) and out-of-facility deaths (0.85). Rank correlation indicated moderate agreement for adults (0.75-0.79). Conclusions: Whilst CCVAs identified HIV/AIDS as the leading COD, consistent with PCVA, there is scope for improving the algorithms for use in South Africa.
In this paper, we investigate the impact of both static and dynamic effects of motion on Underwater visible light communication (UVLC) channels. While previous studies have focused on static channel modeling, we argue that dynamic channel modeling is crucial for accurate UVLC analysis. To model static and dynamic UVLC channels, we use the Monte Carlo ray tracing (MCRT) method in Zemax Optics Studio; a reliable and practical setup simulator that produces results similar to experimental data. We evaluate the effect of channel coding on system performance by comparing nine different combinations and using Goodness-of-Fit (GoF) tests to determine the best-fit distribution. Our results reveal that the static case outperforms the dynamic case in terms of raw performance without any coding. However, we also show that the bit error rate (BER) is severely impacted in various realistic scenarios for a dynamic environment. To improve the BER and achieve adequate received signal quality, we recommend using convolutional codes. This paper emphasizes the importance of dynamic channel modeling in UVLC and provides practical solutions to enhance the UVLC performance in dynamic environments. The findings of our study provide valuable insights into the performance of UVLC systems and emphasize the need for researchers and designers to account for the dynamic realistic behavior in the underwater channel to achieve optimal performance in UVLC systems for underwater communication applications.
The assembly line biosynthesis of the powerful anticancer‐antiviral didemnin cyclic peptides is proposed to follow a prodrug release mechanism in Tristella bacteria. This strategy commences with the formation of N‐terminal prodrug scaffolds and culminates in their cleavage during the cellular export of the mature products. In this study, a comprehensive exploration of the genetic and biochemical aspects of the enzymes responsible for both the assembly and cleavage of the acylated peptide prodrug scaffolds is provided. This process involves the assembly of N‐acyl‐polyglutamine moieties orchestrated by the nonribosomal peptide synthetase DidA and the cleavage of these components at the post‐assembly stage by DidK, a transmembrane CAAX hydrolase homolog. The findings not only shed light on the complex prodrug mechanism that underlies the synthesis and secretion of didemnin compounds but also offer novel insights into the expanded role of CAAX hydrolases in microbes. Furthermore, this knowledge can be leveraged for the strategic design of genome mining approaches aimed at discovering new bioactive natural products that employ similar prodrug biochemical strategies.
Dispersal drives extinction-recolonization dynamics of metapopulations and is necessary for endangered species to recolonize former ranges. Yet few studies quantify dispersal and even fewer examine consistency of dispersal over many years. The northern elephant seal ( Mirounga angustirostris ) provides an example of the importance of dispersal. It quickly recolonized its full range after near extirpation by 19 th century hunting, and though dispersal was observed it was not quantified. Here we enumerate lifetime dispersal events among females marked as pups at two colonies during 1994-2010, then correct for detection biases to estimate bidirectional dispersal rates. An average of 16% of females born at the Piedras Blancas colony dispersed northward 200 km to breed at Año Nuevo, while 8.0% of those born at Año Nuevo dispersed southward to Piedras Blancas. The northward rate fluctuated considerably but was higher than southward in 15 of 17 cohorts. The population at Piedras Blancas expanded 15-fold during the study, while Año Nuevo’s declined slightly, but the expectation that seals would emigrate away from high density colonies was not supported. During the 1990s, dispersal was higher away from the small colony toward the large. Moreover, cohorts born later at Piedras Blancas, when the colony had grown, dispersed no more than early cohorts. Consistently high natal dispersal in northern elephant seals means the population must be considered a single large unit in terms of response to environmental change. High dispersal was fortuitous to the past recovery of the species, and continued dispersal means elephant seals will likely expand their range further.
Introducing a special commentary section focused on geoeconomics, this paper reviews why such commentary is especially timely given current world events and the break‐down in neoliberal globalisation. It thereby points to the geo‐historical importance of the call for critical geoeconomics made by Mallin and Sidaway (2023a), and also introduces the backgrounds of the five commentators on their article's key contributions.
Prior to the COVID‐19 pandemic, food insecurity and depression were growing public health concerns among graduate students. Yet, little is known about how COVID‐19‐related stressors exacerbated these health outcomes among graduate students. To address this research gap, this study examined two types of COVID‐19‐related stressors, anticipated concerns about remote learning and challenges interfering with academic and research responsibilities, in relation to food insecurity and depressive symptoms among public university graduate students. Between August and October 2020, 631 graduate students who utilised basic needs services from seven University of California campuses completed an online survey assessing the effects of COVID‐19 on their academic experiences, mental health, and basic needs security. Regression analyses examined associations of COVID‐19‐related concerns and COVID‐19‐related challenges with food insecurity as well as COVID‐19‐related concerns and COVID‐19‐related challenges in relation to depressive symptoms. All four models were adjusted for age, sex, race and ethnicity, campus affiliation, and living with a partner. Models examining food security status as the dependent variable were adjusted for depressive symptoms and vice versa. Graduate students concerned about delayed graduation, post‐graduate employment, isolation from faculty and not having access to healthcare reported higher counts of depressive symptoms. Challenges associated with higher counts of depressive symptoms included caring for family more than usual, spending more time on errands and not paying for utilities in full. Students concerned about accessing healthcare had higher odds of experiencing food insecurity. Challenges associated with food insecurity included spending more time on errands, being unable to afford housing and sending money to family members during the pandemic. Our findings illuminate the pandemic's deleterious consequences on graduate students' mental health and food security, underscoring the need for strong academic and basic needs programs and policies.
The habitability of Europa is a property within a system, which is driven by a multitude of physical and chemical processes and is defined by many interdependent parameters, so that its full characterization requires collaborative investigation. To explore Europa as an example, integrated system to yield a complete picture of its habitability, the Europa Clipper mission has three primary science objectives: (1) characterize the ice shell and ocean including their heterogeneity, properties, and the nature of surface–ice–ocean exchange; (2) characterize Europa’s composition including any non-ice materials on the surface and in the atmosphere, and any carbon-containing compounds; and (3) characterize Europa’s geology including surface features and localities of high science interest. The mission will also address several cross-cutting science topics including the search for any current or recent activity in the form of thermal anomalies and plumes, performing geodetic and radiation measurements, and assessing high-resolution, co-located observations at select sites to provide reconnaissance for a potential future landed mission. Synthesizing the mission’s science measurements, as well as incorporating remote observations by Earth-based observatories, the James Webb Space Telescope, and other space-based resources, to constrain Europa’s habitability, is a complex task and is guided by the mission’s Habitability Assessment Board (HAB).
Noncoding DNA is central to our understanding of human gene regulation and complex diseases1,2, and measuring the evolutionary sequence constraint can establish the functional relevance of putative regulatory elements in the human genome3–9. Identifying the genomic elements that have become constrained specifically in primates has been hampered by the faster evolution of noncoding DNA compared to protein-coding DNA¹⁰, the relatively short timescales separating primate species¹¹, and the previously limited availability of whole-genome sequences¹². Here we construct a whole-genome alignment of 239 species, representing nearly half of all extant species in the primate order. Using this resource, we identified human regulatory elements that are under selective constraint across primates and other mammals at a 5% false discovery rate. We detected 111,318 DNase I hypersensitivity sites and 267,410 transcription factor binding sites that are constrained specifically in primates but not across other placental mammals and validate their cis-regulatory effects on gene expression. These regulatory elements are enriched for human genetic variants that affect gene expression and complex traits and diseases. Our results highlight the important role of recent evolution in regulatory sequence elements differentiating primates, including humans, from other placental mammals.
Here we report on a rare and opportunistic acoustic turn-taking with an adult female humpback whale, known as Twain, in Southeast Alaska. Post hoc acoustic and statistical analyses of a 20-min acoustic exchange between the broadcast of a recorded contact call, known as a ‘whup/throp’, with call responses by Twain revealed an intentional human-whale acoustic (and behavioral) interaction. Our results show that Twain participated both physically and acoustically in three phases of interaction (Phase 1: Engagement, Phase 2: Agitation, Phase 3: Disengagement), independently determined by blind observers reporting on surface behavior and respiratory activity of the interacting whale. A close examination of both changes to the latency between Twain’s calls and the temporal matching to the latency of the exemplar across phases indicated that Twain was actively engaged in the exchange during Phase 1 (Engagement), less so during Phase 2 (Agitation), and disengaged during Phase 3 (Disengagement). These results, while preliminary, point to several key considerations for effective playback design, namely the importance of salient, dynamic and adaptive playbacks, that should be utilized in experimentation with whales and other interactive nonhuman species.
This study examines how parents' and children's explanatory talk and exploratory behaviors support children's causal reasoning at a museum in San Jose, CA in 2017. One‐hundred‐nine parent–child dyads (3–6 years; 56 girls, 53 boys; 32 White, 9 Latino/Hispanic, 17 Asian‐American, 17 South Asian, 1 Pacific Islander, 26 mixed ethnicity, 7 unreported) played at an air flow exhibit with a nonobvious causal mechanism. Children's causal reasoning was probed afterward. The timing of parents' explanatory talk and exploratory behaviors was related to children's systematic exploration during play. Children's exploratory behavior, and parents' goal setting during play, were related to children's subsequent causal reasoning. These findings support the hypothesis that children's exploration is related to both internal learning processes and external social scaffolding.
Origami structures have been widely explored in robotics due to their many potential advantages. Origami robots can be very compact, as well as cheap and efficient to produce. In particular, they can be constructed in a flat format using modern manufacturing techniques. Rotational motion is essential for robotics, and a variety of origami rotational joints have been proposed in the literature. However, few of these are even approximately flat-foldable. One potential enabler of flat origami rotational joints is the inclusion of lightweight pneumatic pouches which actuate the origami’s folds; however, pouch actuators only enable a relatively small amount of rotational displacement. The previously proposed four-vertex origami is a flat-foldable structure that provides an angular multiplier for a pouch actuator, but suffers from a degenerate state. This paper presents a novel rigid origami, the self-lock origami, which eliminates this degeneracy by slightly relaxing the assumption of flat-foldability. It includes the earwig wing-inspired origami pattern with inextensible and flexible components. This joint is analyzed in terms of a trade-off between the angular multiplier and the mechanical advantage. Furthermore, the self-lock origami is a modular joint that can be connected to similar or different joints to produce complex movements for various applications; three different manipulator designs are introduced as a proof of concept.
Offshore aquaculture is a growing industry, but a lack of social acceptance is limiting development, including within the USA. We used the Gulf Coast of Florida, where there has been industry and government interest in development, as a case study to explore offshore aquaculture potential and methods for integrating stakeholder concerns into offshore aquaculture development. We assessed (1) social acceptance of offshore aquaculture in the Florida Gulf Coast using public comments; (2) site suitability for offshore development using social, biological, and technical data; and (3) potential impacts of offshore aquaculture on communities using socioeconomic vulnerability indices. We found that many stakeholders distrust policymakers and industry and have concerns about potential environmental impacts. We created species-specific suitability maps for red drum (Sciaenops ocellatus) and almaco jack (Seriola rivoliana), demonstrating that large areas of the Gulf are suitable for offshore aquaculture development. We show that many coastal and fishing-reliant communities have existing vulnerabilities that aquaculture development could affect, but the public comments did not reflect these. To gain social acceptance, industry and government agencies will need to better incorporate public feedback into planning processes in a meaningful way. Consulting local communities and adapting projects in response to their concerns can help to secure social license for offshore aquaculture.
Along the strike of subduction zones, tectonic tremor episodicity is segmented on a geologic scale. Here, we study how this segmentation reflects large‐scale variations of the structure and conditions of the fault interface where tremor is generated. We try to understand which properties of the hydraulic system of the fault allow elementary tremor sources to synchronize, leading to the emergence of long‐period, large‐scale episodic activity. We model tremor sources as being associated with rapid openings of low‐permeability valves in the fault zone, which channels the upward flow of metamorphic fluids. Valve openings cause pressure transients that allow interaction between sources. In such a system, tremor activity is thus controlled by unsteady fluid circulation. Using numerical simulations of fluid flow, we explore the impact of valve spatial distribution and fluid flux on the emergence of large‐scale patterns of tremor activity. We show that when valves are densely distributed and submitted to near‐critical input flux, they synchronize and generate more episodic activity. Based on our model, the most periodic and spatially coherent tremor bursts should thus be emitted from segments densely populated with valves, and therefore of lower permeability than less synchronized segments. The collective activity of their valve population is responsible for fluid‐pressure cycling at the subduction scale. In the tremor zone of Shikoku, Japan, the most temporally clustered segment coincides with a downgoing seamount chain, suggesting that the segmentation of the fault zone permeability, and hence of tremor activity, could be inherited from the topography of the subducting oceanic plate.
We evaluate the impact of anthropogenic carbon (Cant) accumulation on multiple ocean acidification (OA) metrics throughout the water column and across the major ocean basins using the GLODAPv2.2016b mapped product. OA is largely considered a surface‐intensified process caused by the air‐to‐sea transfer of Cant; however, we find that the partial pressure of carbon dioxide gas (pCO2), Revelle sensitivity Factor (RF), and hydrogen ion concentration ([H⁺]) exhibit their largest responses to Cant well below the surface (>100 m). This is because subsurface seawater is usually less well‐buffered than surface seawater due to the accumulation of natural carbon from organic matter remineralization. pH and aragonite saturation state (ΩAr) do not exhibit spatially coherent amplified subsurface responses to Cant accumulation in the GLODAPv2.2016b mapped product, though nonlinear characteristics of the carbonate system work to amplify subsurface changes in each OA metric evaluated except ΩAr. Regional variability in the vertical gradients of natural and anthropogenic carbon create regional hot spots of subsurface intensified OA metric changes, with implications for vertical shifts in biologically relevant chemical thresholds. Cant accumulation has resulted in subsurface pCO2, RF, and [H⁺] changes that significantly exceed their respective surface change magnitudes, sometimes by >100%, throughout large expanses of the ocean. Such interior ocean pCO2 changes are outpacing the atmospheric pCO2 change that drives OA itself. Re‐emergence of these waters at the sea surface could lead to elevated CO2 evasion rates and reduced ocean carbon storage efficiency in high‐latitude regions where waters do not have time to fully equilibrate with the atmosphere before subduction.
Ecosystems around the world are continuously undergoing recovery from anthropogenic disturbances like climate change, overexploitation, and habitat destruction. Coral reefs are a prime example of a threatened ecosystem and coral recruitment is a critical component of reef recovery from disturbances. Reef fishes structure this recruitment by directly consuming macroalgae and coral recruits or by indirectly altering the substrate to facilitate coral settlement (e.g., grazing scars). However, how these direct and indirect mechanisms vary through time remains largely unknown. Here, we quantified coral recruitment on settlement tiles with divots that mimic grazing scars and caging treatments to exclude or allow fish feeding over 3 years at Palmyra Atoll in the Pacific Ocean. We found that the positive and negative effects of fishes on coral recruitment varies through time. After 3 years, both grazing scars and fish grazing no longer predicted coral recruitment, suggesting that the role of fishes decreases over time. Our results emphasize that reef fish populations are important in promoting initial coral recovery after disturbances. However, over time, factors like the environment may become more important. Future work should continue to explore how the strength and direction of top-down control by consumers varies through time across multiple ecosystems.
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7,180 members
Sasha Tozzi
  • Department of Ocean Sciences
Marc Perry
  • Genomics Institute
Diane Gifford-Gonzalez
  • Department of Anthropology
John Pearse
  • Department of Ecology & Evolutionary Biology
1156 High St, 95064, Santa Cruz, California, United States
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University of California