Intraspecific trait variability is a key feature underlying high Arctic plant community resistance to climate warming

In the high Arctic, plant community species composition generally responds slowly to climate warming, whereas less is known about the community functional trait responses and consequences for ecosystem functioning. The slow species turnover and large distribution ranges of many Arctic plant species suggest a significant role of intraspecific trait variability in functional responses to climate change. Here we compare taxonomic and functional community compositional responses to a long-term (17-year) warming experiment in Svalbard, Norway, replicated across three major high Arctic habitats shaped by topography and contrasting snow regimes. We observed taxonomic compositional changes in all plant communities over time. Still, responses to experimental warming were minor and most pronounced in the drier habitats with relatively early snowmelt timing and long growing seasons (Cassiope and Dryas heaths). The habitats were clearly separated in functional trait space, defined by 12 size- and leaf economics-related traits, primarily due to interspecific trait variation. Functional traits also responded to experimental warming, most prominently in the Dryas heath and mostly due to intraspecific trait variation. Leaf area and mass increased and leaf δ15N decreased in response to the warming treatment. Intraspecific trait variability ranged between 30% and 71% of the total trait variation, reflecting the functional resilience of those communities, dominated by long-lived plants, due to either phenotypic plasticity or genotypic variation, which most likely underlies the observed resistance of high Arctic vegetation to climate warming. We further explored the consequences of trait variability for ecosystem functioning by measuring peak season CO2 fluxes. Together, environmental, taxonomic, and functional trait variables explained a large proportion of the variation in net ecosystem exchange (NEE), which increased when intraspecific trait variation was accounted for. In contrast, even though ecosystem respiration and gross ecosystem production both increased in response to warming across habitats, they were mainly driven by the direct kinetic impacts of temperature on plant physiology and biochemical processes. Our study shows that long-term experimental warming has a modest but significant effect on plant community functional trait composition and suggests that intraspecific trait variability is a key feature underlying high Arctic ecosystem resistance to climate warming.publishedVersio

A Case Report of Unilateral Horner's Syndrome and 6th Nerve Palsy in Giant Cell Arteritis

To present a case of concurrent unilateral Horner's syndrome and a 6th nerve palsy as the diagnostic presentation of giant cell arteritis

Arachnoid cyst resulting in sixth nerve palsy in a child

A 2 year old presented with incomitant esotropia and abduction deficit consistent with sixth nerve palsy. Neuroimaging revealed an arachnoid cyst on the left. Neurosurgical shunting followed by strabismus surgery relieved the abduction deficit and esotropia. An arachnoid cyst may be a rare cause of acquired sixth nerve palsy and strabismus in children

Visits to the Pediatric Emergency Department for Eye Conditions Before and During the COVID-19 Pandemic

Introduction: The use of the emergency department (ED) has been increasing, and many visits occur for non-urgent conditions. A similar trend was found among adult visits to the ED for ocular conditions. In this study we analyzed the impact of sociodemographic factors, presentation timing, and the COVID-19 pandemic on pediatric ED (PED) encounters for ophthalmologic conditions. It is important to identify the multifold factors associated with overutilization of the ED for non-urgent conditions. Caring for these patients in an outpatient clinical setting is safe and effective and could decrease ED crowding; it would also prevent delays in the care of other patients with more urgent medical problems and lower healthcare costs. Methods: We retrospectively reviewed electronic health records of PED ocular-related encounters at two children’s hospitals before (January 2014-May 2018) and during the COVID-19 pandemic (March 2020-February 2021). Encounters were categorized based on the International Classification of Diseases codes into “emergent,” “urgent,” and non-urgent” groups. We analyzed associations between sociodemographic factors and degrees of visit urgency. We also compared visit frequencies, degrees of urgency, and diagnoses between pre-pandemic and pandemic data.  Results: Pre-pandemic ocular-related PED encounters averaged 1,738 per year. There were highly significant sociodemographic associations with degrees of urgency in PED utilization. During the 12-month pandemic timeframe, encounter frequency contracted to 183. Emergent visits decreased from 21% to 11%, while the proportions of urgent and non-urgent encounters were mostly unchanged. The most common pre-pandemic urgent diagnosis was corneal abrasion (50%), while visual disturbance was most common during the pandemic (92%). During both time periods, eye trauma was the most frequent emergent encounter and conjunctivitis was the most common non-urgent encounter.  Conclusion: Sociodemographic factors may be associated with different types of PED utilization for ocular conditions. Unnecessary visits constitute major inefficiency from a healthcare-systems standpoint. The marked decrease in PED utilization and differing proportions of ocular conditions encountered during the pandemic may reflect a decrease in incidence of many of those conditions by social distancing; these changes may also reflect altered parental decisions about seeking care

Consensus Statement for the Management and Treatment of Sturge-Weber Syndrome: Neurology, Neuroimaging, and Ophthalmology Recommendations.

BackgroundSturge-Weber syndrome (SWS) is a sporadic, neurocutaneous syndrome involving the skin, brain, and eyes. Because of the variability of the clinical manifestations and the lack of prospective studies, consensus recommendations for management and treatment of SWS have not been published.ObjectiveThis article consolidates the current literature with expert opinion to make recommendations to guide the neuroimaging evaluation and the management of the neurological and ophthalmologic features of SWS.MethodsThirteen national peer-recognized experts in neurology, radiology, and ophthalmology with experience treating patients with SWS were assembled. Key topics and questions were formulated for each group and included (1) risk stratification, (2) indications for referral, and (3) optimum treatment strategies. An extensive PubMed search was performed of English language articles published in 2008 to 2018, as well as recent studies identified by the expert panel. The panel made clinical practice recommendations.ConclusionsChildren with a high-risk facial port-wine birthmark (PWB) should be referred to a pediatric neurologist and a pediatric ophthalmologist for baseline evaluation and periodic follow-up. In newborns and infants with a high-risk PWB and no history of seizures or neurological symptoms, routine screening for brain involvement is not recommended, but brain imaging can be performed in select cases. Routine follow-up neuroimaging is not recommended in children with SWS and stable neurocognitive symptoms. The treatment of ophthalmologic complications, such as glaucoma, differs based on the age and clinical presentation of the patient. These recommendations will help facilitate coordinated care for patients with SWS and may improve patient outcomes