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Circadian rhythm disturbances, especially circadian phase delays are associated with impulsive behaviors and have been implicated in psychiatric disorders. Chronotype is a developmentally regulated proxy measure of circadian phase. Past studies have investigated the relationship between chronotype and trauma and found that trauma is associated with evening chronotypes, suggesting the course of chronotype development may be affected by adverse childhood experiences (ACEs). However, the relationships among chronotype, impulsivity and ACEs have largely been studied in a pairwise manner using small, cross-sectional cohorts. We hypothesized that in a cohort of high-risk youth, childhood trauma would be associated with later chronotype, and later chronotype would be associated with higher rates of impulsivity. We analyzed a cross-sectional sample (n = 966) from Year 2 of adolescents at high risk for psychiatric disorders from the ABCD study who were characterized for chronotype, stressful life events, and impulsivity. We used a hierarchical regression model to examine the relationship between chronotype, stressful life events, and impulsivity using the Munich Chronotype Questionnaire (MCTQ), the Life Events Scale, Urgency, Premeditation, Perseverance and Sensation Seeking (UPPS) Impulsive Behavior scale. We found associations between eveningness, stressful life events, and all dimensions of impulsivity. Increased eveningness was associated with a higher number of stressful life events and increased impulsivity. Understanding the role of stressful life events and impulsivity in those predisposed towards eveningness is useful because it may improve our understanding of the biological mechanisms that contribute to psychiatric disorders, and lead to better prevention and treatment efforts using interventions such as increased lifestyle regularity and daytime light exposure. • Impulsivity, later chronotype, stressful life events.→poor mental/physical health • Evening chronotype, stressful life events, and impulsivity are interrelated. • Investigation may help identify interventions to promote mental health & wellbeing. • Future work in prospective studies to clarify these factors will be essential. [ABSTRACT FROM AUTHOR]

[Display omitted] • Peat fires reduce tree species diversity. • Tree species richness and diversity recovers 30 yr after fires at site level. • At landscape scale species richness and diversity continues to increase at fire frequency > 80 yr. • Revegetation strategies recommended with 'the increaser group' trees. Tropical peat swamp forests contain diverse plant communities that support many endangered flora and fauna species. These forests are increasingly threatened by disturbances such as drainage, logging, and subsequent fire, yet little is known about tree species recovery from these threats. Tree species richness and diversity were measured in peat swamp forests of Central Borneo regenerating naturally after fires from 139 chronosequence plots. Our findings indicated that two to three decades after fire, similar levels of richness and diversity to relatively undisturbed reference forest are reached within sites. However, when averaged across landscapes our modelling shows that fires of average frequency of 50 years, or even 100 years, can substantially suppress tree species richness and diversity. Thus, even rare fires can reduce the species richness and diversity of tropical peat swamp forests. Two groups of tree species drove the difference in richness and diversity between disturbed and reference forests: 'decreasers', occupying recently burnt forest and declining with fire exclusion, and 'increasers', that were only present in less disturbed forests and absent or rare in recently burnt forests. The decreasers were more common than the increasers. We conclude that peat swamp forests can recover adequately from fires through natural regeneration, and it is possible that artificial planting may speed up this process. Where possible, excluding fire from tropical peat forests will help to maintain the diversity of these threatened ecosystems and promote their recovery. [ABSTRACT FROM AUTHOR]

• Bipolar disorder is characterized by pervasive disruptions in circadian rhythms. • Lithium has effects on cellular and behavioral rhythms. • The effects of lithium on circadian rhythms are context- and dose-dependent. • Lithium responsive bipolar disorder patients show distinct circadian rhythm characteristics: morning chronotype, less variable behavioral rhythms, and shorter period in cultured cells. Bipolar disorder (BD) is characterized by disrupted circadian rhythms affecting sleep, arousal, and mood. Lithium is among the most effective mood stabilizer treatments for BD, and in addition to improving mood symptoms, stabilizes sleep and activity rhythms in treatment responsive patients. Across a variety of experimental models, lithium has effects on circadian rhythms. However, uncertainty exists as to whether these actions directly pertain to lithium's therapeutic effects. Here, we consider evidence from mechanistic studies in animals and cells and clinical trials in BD patients that identify associations between circadian rhythms and the therapeutic effects of lithium. Most evidence indicates that lithium has effects on cellular circadian rhythms and increases morningness behaviors in BD patients, changes that may contribute to the therapeutic effects of lithium. However, much of this evidence is limited by cross-sectional analyses and/or imprecise proxy markers of clinical outcomes and circadian rhythms in BD patients, while mechanistic studies rely on inference from animals or small numbers of patients. Further study may clarify the essential mechanisms underlying lithium responsive BD, better characterize the longitudinal changes in circadian rhythms in BD patients, and inform the development of therapeutic interventions targeting circadian rhythms. [ABSTRACT FROM AUTHOR]

Biphasic squamoid alveolar renal cell carcinoma is a newly described rare morphologic variant of papillary renal cell carcinoma. Its characteristic histomorphology and immunophenotype have been well described in the literature. Namely, BSARCC is composed of a dual-cell population with nests of larger squamoid cells surrounded by a single layer of cuboidal cells in alveolar arrangements. Invariably, the squamoid component expresses cyclin D1. More recently, MET alterations have been identified within a subset of BSARCC, raising the possibility for targeted MET inhibitor therapy. To the best of our knowledge the cytomorphologic features of BSARCC have yet to be described. Herein we correlate the cytologic features (percutaneous image-guided fine needle aspiration) of BSARCC to its corresponding histomorphology and immunophenotype (core needle biopsy). • Biphasic squamoid alveolar renal cell carcinoma (BSARCC) is a newly described rare morphologic variant of papillary renal cell carcinoma. • BSARCC is composed of a dual-cell population with nests of larger squamoid cells surrounded by a single layer of cuboidal cells in alveolar arrangements. • To our knowledge, the cytologic features of BSARCC have not been described in the literature. We present a case where the two distinct tumor cells populations and cytophagocytosis were appreciable on smears. [ABSTRACT FROM AUTHOR]

• Recombinant virus-like particle vaccine was safely administered to rhesus macaques. • Vaccination generated high-titer neutralizing antibody responses. • Multivalent BK/JC polyomavirus vaccine was as effective as monovalent vaccines. • High neutralizing titers were sustained for 92 weeks without appreciable decline. In 2019, there were about 100,000 kidney transplants globally, with more than a quarter of them performed in the United States. Unfortunately, some engrafted organs are lost to polyomavirus-associated nephropathy (PyVAN) caused by BK and JC viruses (BKPyV and JCPyV). Both viruses cause brain disease and possibly bladder cancer in immunosuppressed individuals. Transplant patients are routinely monitored for BKPyV viremia, which is an accepted hallmark of nascent nephropathy. If viremia is detected, a reduction in immunosuppressive therapy is standard care, but the intervention comes with increased risk of immune rejection of the engrafted organ. Recent reports have suggested that transplant recipients with high levels of polyomavirus-neutralizing antibodies are protected against PyVAN. Virus-like particle (VLP) vaccines, similar to approved human papillomavirus vaccines, have an excellent safety record and are known to induce high levels of neutralizing antibodies and long-lasting protection from infection. In this study, we demonstrate that VLPs representing BKPyV genotypes I, II, and IV, as well as JCPyV genotype 2 produced in insect cells elicit robust antibody titers. In rhesus macaques, all monkeys developed neutralizing antibody titers above a previously proposed protective threshold of 10,000. A second inoculation, administered 19 weeks after priming, boosted titers to a plateau of ≥ 25,000 that was maintained for almost two years. No vaccine-related adverse events were observed in any macaques. A multivalent BK/JC VLP immunogen did not show inferiority compared to the single-genotype VLP immunogens. Considering these encouraging results, we believe a clinical trial administering the multivalent VLP vaccine in patients waiting to receive a kidney transplant is warranted to evaluate its ability to reduce or eliminate PyVAN. [ABSTRACT FROM AUTHOR]

Some patients with polycystic kidney disease present with renal neoplasia. In rare instances, tumors occur secondary to contiguous deletions of the PKD1 and TSC2 genes. Identification of PKD1/TSC2 contiguous gene deletion syndrome may improve prognostication and guide genetic counseling. To determine the incidence of renal neoplasia among patients undergoing nephrectomy for polycystic kidney disease (PKD), we queried our institutional nephrectomy registry (years 2000–2020). Approximately 4% (231 of 5757) of patients who underwent nephrectomy had PKD, and 26 of these 231 patients (11.3%) had renal neoplasia. Tumors from an additional two patients with PKD were also evaluated. Patients with PKD who had tuberous sclerosis complex (TSC)-associated renal neoplasia were screened for PKD1/TSC2 contiguous gene deletion syndrome (CGS) using single nucleotide polymorphism arrays. The median age of patients with PKD and renal neoplasia at nephrectomy was 54 yr. The median tumor size was 2.0 cm and the tumors were predominantly of low grade and stage. The tumors consisted of 23 renal cell carcinomas (RCCs), one epithelioid angiomyolipoma, and four angiomyolipomas. The median follow-up was 59.5 mo (n = 26) and only one patient with clear cell RCC developed metastases. Two patients with angiomyolipomas had PKD1/TSC2 CGS. Our results support screening of patients with PKD and TSC-associated renal neoplasia as well as TSC patients with cystic renal disease for CGS, as identification of patients with CGS can better define the manifestation and prognosis of CGS and guide counseling regarding patterns of inheritance. We identified patients with abnormal kidney cell growth (called renal neoplasia) among those undergoing removal of kidney tissue for polycystic kidney disease (PKD) and patients with a syndrome involving deletions in two genes, called PKD1/TSC2 contiguous gene deletion syndrome (CGS) at our institution. Of 231 PKD patients with removal of kidney tissue, 11.3% had renal neoplasia, and two patients with angiomyolipoma tumors had PKD1/TSC2 CGS. Detection of renal neoplasia associated with a condition called tuberous sclerosis complex in PKD may increase the identification of patients with PKD1/TSC2 CGS and guide patient counseling regarding outcomes and patterns of inheritance. [ABSTRACT FROM AUTHOR]

Joining techniques for multi-material structures are critical for increased use of lightweight materials in the automotive industry. This paper investigates the combined effect of spew geometry and load eccentricity angle on the mechanical performance of bonded single-lap joints (SLJ), employing carbon-fibre thermoplastic composite and aluminium adherends. Spew geometries – half-rounded and flat, and eccentricity angles – 0.48°, 0.62°, 0.78°, and 0.91°, considered here, are relevant to typical joints in thin-walled automotive structures. Of the geometries investigated, in the first the excess adhesive was allowed to take its "natural" half-rounded shape, while the second involved a simple additional step, suitable for high-volume production. Moreover, considering the use of dissimilar adherends and crash-durable epoxy adhesives, and limited accessibility to both adherend free ends in practical joints, the flat-spew geometry was formed at the free end of the composite adherend, resulting in SLJs with asymmetrical spew geometries. The SLJs were tested at dynamic crash loading rates (0.5 m/s and 3 m/s) as well as in-service quasi-static loading rates. The load eccentricity was found to significantly affect the half-rounded spew joint performance, particularly at the dynamic loading rates. The asymmetric spew shape significantly minimised the detrimental eccentricity effects, at all loading rates. The SLJs with flat-spew shows 92%−120% higher energy absorption under dynamic loading, relative to half-rounded spew joints. The joint deformation mechanisms and post-failure surfaces are examined. Further, finite element analysis was performed to understand the influence of the investigated spew geometries on the adhesive stress distribution. The proposed flat spew geometry achieved the lowest peel stresses and the highest shear to peel stress ratio, in addition to having low sensitivity to changes in geometry. [ABSTRACT FROM AUTHOR]

Understanding the nature and extent of global amphibian declines has been hampered because pre-decline data rarely exist, post-decline data can be incomplete and amphibian population fluctuations can be influenced by multiple factors. Importantly, data deficiencies have impeded assessments of the roles of the pathogen, chytrid fungus Batrachochytrium dendrobatidis , and co-occurring host or competitor species in amphibian population declines. We used dynamic occupancy models to examine the influence of chytrid upon two sympatric frog species and their interactions. Models combined sporadic historic data and more intensive post-decline data collected over a 55-year period (1958–2012) for the threatened Spotted Tree Frog Litoria spenceri and non-threatened Lesueur's Frog L. lesueurii. Our analysis indicated an approximate 50 % decline in L. spenceri site occupancy. This decline was most severe at sites when both chytrid and L. lesueurii were present. Further L. spenceri declines are predicted without intervention. In contrast, L. lesueurii tended to become more prevalent over time, and changes in L. lesueurii occurrence over time were not associated with chytrid or L. spenceri occurrence. Efforts to conserve L. spenceri when threatened by chytrid may be most effective at sites where L. lesueurii (a potential pathogen reservoir) is absent. Our work highlights the risk posed by sympatric pathogen reservoir species for susceptible species. This study not only demonstrates the value of long-term population monitoring, but how incorporation of sporadic, historic records may provide valuable insights into processes underlaying species decline and recovery. [ABSTRACT FROM AUTHOR]

Indirect surveillance methods, such as remote cameras and acoustic monitoring, are increasingly used in ecological surveys. The time to deploy these devices includes initial setup, possible maintenance, retrieval and then a potentially large investment in the processing of the collected data. Thus, costs will increase with both the number of sites at which devices are deployed and the time they remain in the field, creating a trade-off between these factors when aiming to maximise the number of sites with detections. Here we examine a scenario in which a target species occupies a proportion of the possible survey sites (ψ), establishing a new site has a fixed cost (c), each survey of a site entails a cost per unit of survey effort (t), there is imperfect detection of the species during each survey such that the probability of failing to detect the species with a unit of survey effort is q when the species is present, and there is a total budget that can be allocated to establishing and surveying sites (B). We show that the expected number of sites with detections is maximised by surveying each site with a particular amount of survey effort (v) that depends only on q and c. This analytical result can be used by researchers to optimise their survey effort prior to field work and provide opportunities for optimal allocation of their survey budget. We illustrate the method with an application to surveys of the threatened Leadbeater's Possum (Gymnobelidus leadbeateri). • Surveys can be optimised with a limited budget for max sites with detections. • Optimal survey effort depends on site establishment cost and detection probability. • Leadbeater's Possum survey methods are close to optimal. • Solution is not overly sensitive to survey effort or site establishment cost. [ABSTRACT FROM AUTHOR]

Hounsfield units (HU), typically measured at L1-L2, have been identified as a surrogate marker for lumbar Bone Mineral Density (BMD). However, concern remains that L1-L2 BMD may not fully capture BMD differences throughout the lumbosacral spine and inadvertently provide inaccurate assessment. To evaluate the impact of how conventional HU evaluation relates to local HU at commonly instrumented levels, and to evaluate the impact of age and postmenopausal state on HU in the lumbar spine. Cross sectional comparative study. Consecutive female patients presenting to a spine clinic between April 2017 and January 2019 who underwent lumbar CT were selected. Previous lumbar surgery, tumor, fracture or infection were excluded. HU were assessed on lumbar CT by placing an elliptical region of interest confined to the medullary space of the vertebral body, and avoiding cortical bone or sclerosis. HU measurements were performed for L1-S1 in 7 regions of each vertebral body: mid-sagittal; axial-superior, waist, inferior; axial at the waist–anterior, middle, posterior. Patients were divided based on whether they were pre- or postmenopausal. HU were compared between the pre- and postmenopausal cohorts using student t-test or Mann-Whitney u-test. The difference between routinely used L1-L2 average HU and local HU in each region was calculated and compared between groups. Association of age and menopausal state with HU was assessed using regression analyses. Forty-eight patients, 18 premenopausal and 30 postmenopausal were included. The postmenopausal group was significantly older (67 versus 41 years; p<0.0001). Postmenopausal women had lower HU in all regions at all levels (p<0.05), with the mean difference ranging from 45 to 90 HU. Depending on the region, the L1-L2 average was more than 10 units greater than L4 in 30–70% of premenopausal and 40–70% of postmenopausal women (p>0.05). L1-L2 average was also more than 10 units greater than L5 measurements in 17–78% of premenopausal and 40–70% of postmenopausal women (p>0.05, except sagittal region p=0.038). Age, but not BMI showed a significant negative correlation with HU, which was strong in premenopausal and moderate in postmenopausal women. Age and menopausal state account for 35-60% of the variability in HU, except in the posterior region, where they account for 25-45%. Age and postmenopausal state were negatively associated with HU in the lumbosacral spine, and the conventionally used L1-L2 average did not adequately capture local HU variations. Local BMD assessment using HU may provide a more accurate assessment of morphometric characteristics and trabecular milieu in the operative region. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Bone density in the lumbar spine is variable by level and can impact surgical strategy. In the cervical spine, low Hounsfield units (HU) have been associated with cage subsidence. The distribution of HU in the cervical spine has not been established. To define level-specific cervical HU reference values and the relationship between cervical bone density, age, BMI, comorbidities and alignment. Retrospective review at a single center from May 2015 to December 2019. A total of 224 patients, 18 excluded for previous hardware and 5 for known osteoporosis. Hounsfield units. Patients who presented with neck symptoms and had a cervical spine CT for evaluation of pathology or surgical planning were included. Exclusions were hardware on CT, osteoporosis, or cervical deformity. Measurements were performed in 5 regions of each vertebral body (VB) (C2-T1; mid-axial, anterior-axial, posterior-axial, mid-coronal, and mid-sagittal) and 2 regions of the lateral masses (LMs) (C3-C6; mid-cor, mid-sag). The VB measurements were averaged at each level to obtain a composite value of each vertebral body (TotalVB), similarly the mid-cor and mid-sag values were averaged at each LM (TotalLatM). Outliers were excluded pairwise. To evaluate reliability, 6 observers each measured 355 HU values (71 over 5 patients), inter-relater reliability assessed with intraclass correlation coefficients (ICCs). Correlations of composite HU with age, BMI, Charlston Comorbidity Index (CCI) and cervical alignment were evaluated. Average age 57±12 years, mean BMI 28±6 kg/m2, 63.5% male, 90.1% white. Diagnoses included radiculopathy (45.8%), myelopathy (37.9%) and facet arthropathy (46.3%). ICC for HU measurements were as follows: VB, 0.82 mid-axial, 0.59 ant-axial, 0.77 post-axial, 0.88 mid-cor, 0.88 mid-sag; LM, 0.46 mid-sag, 0.61 mid-cor. C4 VB and C4 LM had the highest HU (383.6±71.9 and 480.0±103, respectively) while T1 VB and C6 LM had the lowest (232.3±46.5 and 398.3±98.2, respectively). No significant correlations were found between LM HU and age, BMI, CCI, or alignment. Increased kyphosis was weakly correlated with VB HU at all levels (except C2) strongest correlations at C7 (0.25) and weakest correlation at C3 (0.16). Age and CCI showed weak-moderate correlations with VB HU at all levels (age, r= -0.20 to -0.35; CCI r= -0.28 [C2, C7, T1] to -0.17 [C4]). Our level-specific cervical HU values may be referenced when evaluating cervical BMD. The most reliable measurement technique is on the mid-sag or mid-cor VB, measurement of LMs is less reliable. Bone is least dense in the lower cervical spine, which may influence instrumentation strategies. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Telehealth use in spine surgery has become widespread due to the COVID-19 pandemic. The degree of global adoption remains unknown. To our knowledge, this is the first global survey to directly evaluate provider perspectives surrounding telemedicine use-cases. To elicit the extent of adoption of international spine telehealth. We aimed to explore telemedicine platform used, ease of use, and acceptable use-cases. Cross-sectional email survey, international. Spine Surgeons. Perspectives and practices of spine telemedicine. An anonymous, cross-sectional email survey was sent to the members of AO Spine. Survey questions covered provider experiences with and perceptions of telemedicine. Descriptive statistics were used to depict responses and responses were compared amongst regions. A total of 485 spine providers responded to the survey. As of May 2020, telemedicine usage comprised >39.0% of all visits — up from <10.0% of visits pre-pandemic. A majority of providers (60.5%) performed at least 1 telemedicine visit. The format of "telemedicine" varied widely by region: African (45.2%) and European (50.0%) providers were more likely to use phone calls (no video), whereas North (66.7%) and South American (77.0%) surgeons more commonly used audio-visual telemedicine (p<0.001). North American providers used telemedicine the most during COVID-19 (>60.0% of all visits). There were 81.9% of all providers who "agreed/strongly agreed" telemedicine was easy to use. Respondents tended to "agree" that imaging review, the initial appointment, and postoperative care could be performed using telemedicine. Almost all (95.4%) surgeons preferred at least one in-person visit prior to the day of surgery. Our study noted significant geographical differences in the rate of telemedicine usage and the platform of telemedicine utilized. Spine surgeons found telemedicine feasible for imaging review, initial visits, and follow-up visits although the vast majority still preferred at least one in-person preoperative visit. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]

Hounsfield units (HU), typically measured at L1-L2, have been identified as a surrogate marker for lumbar Bone Mineral Density (BMD). However, concern remains that L1-L2 BMD may not fully capture BMD differences throughout the lumbosacral spine and inadvertently provide inaccurate assessment. To evaluate the impact of age, gender and BMI on lumbar HU, compare the conventional L1-L2 HU measurements with the common levels of degenerative pathology, compare HU measurements among different vertebral levels and evaluate the distribution of HU within the individual vertebral bodies. Cross sectional study. Consecutive patients presenting to a spine clinic between April2017 and January 2019 who underwent lumbar CT were selected. Previous lumbar surgery, tumor, fracture or infection were excluded. HU measurements performed in 7 regions of each vertebral body: Mid-sagittal; Axial–Superior, Waist, Inferior; Axial at the waist–Anterior, Middle, Posterior. Association with age and BMI was evaluated using Pearson product-moment correlation. The difference between L1-L2 and L4 and L5 HU was assessed. Comparison of HU amongst levels and within each level was performed using ANOVA and paired t-tests. A total of 100 patients (mean age=56years, BMI=26.4 kg/m2, 48% males) were included. Age showed a negative correlation with HU in all regions at all levels (p<0.0001). BMI and gender did not show an association with HU. Conventional L1-L2 HU overestimated L4 and L5 HU by at least 10 units in 32–67% of patients, depending on the region. S1 demonstrated higher HU than L3 (p=0.025) and L4 (p=0.029) in the mid-sagittal plane, and higher HU than all other levels in the Superior (p<0.0001) and Waist [overall (p<0.0001), and anterior (p<0.0001), middle (p<0.0001) and posterior (p<0.0001 to p=0.016)] regions in the axial plane, with no other between-level differences. From L1 to L4, HU in the Superior region was significantly lower than that in the Inferior region (p<0.0001 to p=0.003). The opposite was seen at S1, with a decrease in HU from Superior to Waist to Inferior (p<0.0001). At all levels, HU was lower in the Posterior region compared to the Anterior and Middle (p<0.001), with no difference between Anterior and Middle (p>0.05). Although BMD at L1-L2 is often used as a marker of lumbosacral BMD, it may overestimate BMD of other levels. Furthermore, all levels demonstrated differences among various regions. These findings suggest the need for more detailed BMD estimation, especially in patients undergoing spinal instrumentation in whom variations in local BMD can be used to guide surgical planning and could potentially impact clinical outcomes. This abstract does not discuss or include any applicable devices or drugs. [ABSTRACT FROM AUTHOR]