Sex, Scents, and Cephalopods: Factors That Affect Social and Reproductive Behavior in Chambered Nautilus and Oval Squid

Cephalopods are a highly specialized group of molluscs that show a wide range of behavioral patterns. Chambered nautilus (Nautilus pompilius) and oval squid (Sepioteuthis lessoniana) are two very distinct species of cephalopod that both provide unique insight into cephalopod reproductive and social behavior. In experiments utilizing both species, I aimed to fill in knowledge gaps in a range of reproductive behaviors from fundamental responses to conspecifics, to preferred mating habitat. In Chapter 1 and 2 I tested individual nautiluses in a Y-maze where recipients were exposed to paired odors of two donor nautiluses. I collected data on both their choice of scent as well as their tentacle extension behavior as they approached a chosen scent. This allowed me to answer questions concerning whether the opposite or same sex scent were more attractive, as well as if there were individuals’ scents within the opposite sex that were most attractive. In Chapter 3 I completed further analysis of the first two chapters and concluded that Nautilus does not show particular preference for the opposite sex or certain individuals when choosing their scents in a Y-maze. However, Nautilus showed differing patterns of tentacle extension in response to the scent of the opposite sex when compared to the same sex. Further, females and males showed dissimilar topography of response. These findings suggest that detection of conspecific scent may not mean choosing that scent. Further, scent choice and potential mate choice may take place under alternate circumstances, if at all. Finally, that tentacle extension response to conspecific scent may provide evidence for social behavior in chambered nautilus. In Chapter 4 I exposed oval squid to varying habitat types in the laboratory environment and measured the occurrence of two mating behaviors as well as squid location within each habitat. This allowed me to determine the height of the habitat in which squid were most likely to mate (bare, short, or tall) as well as the habitat composition in which they were most likely to mate (seagrass or coral). Results showed that squid choose bare and short habitats and show more variation in mating behavior in the seagrass habitat when compared to coral. Further, habitat choice while mating differed in some measures from habitat choice when not mating. Overall I concluded that oval squid prefer short and bare seagrass habitats for mating, which may indicate where they would mate and spawn in the wild

Population change of invasive Dreissena polymorpha in Douglas Lake from 2003 to 2009.

General EcologyField observations led us to believe that populations of Dreissena polymorpha in Douglas Lake were decreasing. We hypothesized that this change was caused by environmental changes such as a change in water level, population dynamics including an approach to carrying capacity, or the reduction of resources such as suitable substrate and phytoplankton supply. Our study followed many of the methods of the Galligan (2005) survey for the best comparison between years. Sampling gave a greatly reduced number from the past survey; we found a total of 358 D. polymorpha in which 213 were living. While in 2005, Galligan found a total of 3437 D. polymorpha. Biomass was calculated from this sampling and was compared with phytoplankton densities; however there were no significant results. The survey for D. polymorpha veligers was also inconclusive as it produced only one veliger. The decrease in population may be a result of biotic environmental changes or an approach to carrying capacity but further specific research would have to be done to pinpoint a specific mechanism for this decrease. Our research provides valuable knowledge of an invasive species that could contribute to the eventual control of Dreissena polymorpha by natural means.http://deepblue.lib.umich.edu/bitstream/2027.42/64582/1/Duffy_Kittikul_Lewandowski_Sliger_2009.pd

Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors

Context Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs). Objective To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients. Design 12-year prospective, observational study. Participants & Setting We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases. Interventions & Outcome AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310). Results Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650). Conclusions Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course

Protocol and quality assurance for carotid imaging in 100,000 participants of UK Biobank: development and assessment.

Background Ultrasound imaging is able to quantify carotid arterial wall structure for the assessment of cerebral and cardiovascular disease risks. We describe a protocol and quality assurance process to enable carotid imaging at large scale that has been developed for the UK Biobank Imaging Enhancement Study of 100,000 individuals. Design An imaging protocol was developed to allow measurement of carotid intima-media thickness from the far wall of both common carotid arteries. Six quality assurance criteria were defined and a web-based interface (Intelligent Ultrasound) was developed to facilitate rapid assessment of images against each criterion. Results and conclusions Excellent inter and intra-observer agreements were obtained for image quality evaluations on a test dataset from 100 individuals. The image quality criteria then were applied in the UK Biobank Imaging Enhancement Study. Data from 2560 participants were evaluated. Feedback of results to the imaging team led to improvement in quality assurance, with quality assurance failures falling from 16.2% in the first two-month period examined to 6.4% in the last. Eighty per cent had all carotid intima-media thickness images graded as of acceptable quality, with at least one image acceptable for 98% of participants. Carotid intima-media thickness measures showed expected associations with increasing age and gender. Carotid imaging can be performed consistently, with semi-automated quality assurance of all scans, in a limited timeframe within a large scale multimodality imaging assessment. Routine feedback of quality control metrics to operators can improve the quality of the data collection

Towards development of treat to target (T2T) in childhood-onset systemic lupus erythematosus: PReS-endorsed overarching principles and points-to-consider from an international task force

ObjectivesApplication of 'treat-to-target' (T2T) in childhood-onset systemic lupus erythematosus (cSLE) may improve care and health outcomes. This initiative aimed to harmonise existing evidence and expert opinion regarding T2T for cSLE.MethodsAn international T2T Task Force was formed of specialists in paediatric rheumatology, paediatric nephrology, adult rheumatology, patient and parent representatives. A steering committee formulated a set of draft overarching principles and points-to-consider, based on evidence from systematic literature review. Two on-line preconsensus meeting Delphi surveys explored healthcare professionals' views on these provisional overarching principles and points-to-consider. A virtual consensus meeting employed a modified nominal group technique to discuss, modify and vote on each overarching principle/point-to-consider. Agreement of >80% of Task Force members was considered consensus.ResultsThe Task Force agreed on four overarching principles and fourteen points-to-consider. It was agreed that both treatment targets and therapeutic strategies should be subject to shared decision making with the patient/caregivers, with full remission the preferred target, and low disease activity acceptable where remission cannot be achieved. Important elements of the points-to-consider included: aiming for prevention of flare and organ damage; glucocorticoid sparing; proactively addressing factors that impact health-related quality of life (fatigue, pain, mental health, educational challenges, medication side effects); and aiming for maintenance of the target over the long-term. An extensive research agenda was also formulated.ConclusionsThese international, consensus agreed overarching principles and points-to-consider for T2T in cSLE lay the foundation for future T2T approaches in cSLE, endorsed by the Paediatric Rheumatology European Society

Landscape of Familial Isolated and Young-Onset Pituitary Adenomas: Prospective Diagnosis in AIP Mutation Carriers.

Familial isolated pituitary adenoma (FIPA) due to aryl hydrocarbon receptor interacting protein (AIP) gene mutations is an autosomal dominant disease with incomplete penetrance. Clinical screening of apparently unaffected AIP mutation (AIPmut) carriers could identify previously unrecognized disease.This article is freely available via PubMed Central. Click on the 'Additional Link' above to access the full text

Coronal Heating as Determined by the Solar Flare Frequency Distribution Obtained by Aggregating Case Studies

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfv\'en waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, $\alpha=2$ as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed $>$600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: pre-flare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that $\alpha = 1.63 \pm 0.03$. This is below the critical threshold, suggesting that Alfv\'en waves are an important driver of coronal heating.Comment: 1,002 authors, 14 pages, 4 figures, 3 tables, published by The Astrophysical Journal on 2023-05-09, volume 948, page 7