The Eye of the Larval Firefly \u3ci\u3ePhoturis\u3c/i\u3e: A Structural and Functional Description

Fireflies are bioluminescent beetles and members of the holometabolous clade. As holometabola, fireflies interact with their environment during two stages: larva and adult. I studied firefly stemmata, Photuris genus, with the aim of understanding their ecological utility by identifying structural and functional features of the eye. As a first step toward this goal, I used microscopy to characterize the architecture of firefly stemmata. I concluded that Photuris eyes were a type of fusion-stemmata, evidenced by a bi-lobed organization. Each eye contained 88 photoreceptors that contributed dense interlocking-microvilli forming a fused-rhabdom. In the next section, I tested whether stemmata regulated photo-dependent activity. I found that larvae were more active during nocturnal conditions, but unexpectedly, these behavioral patterns were not sufficiently explained by stemmata. Upon excision of the optic nerve, larvae maintained their activity preference to dark conditions, but this behavior was abolished upon removal of their head, suggesting an extraocular mechanism. In the final section, I demonstrated that stemmata were most sensitive to light in the blue/green part of the visible spectrum. Furthermore, using a chromatic adaptation assay, I showed that stemmata photoreceptors were consistent with having more than one spectrally distinct opsin. While a specific behavioral role for the larval eyes remain inconclusive, the macro- and ultrastructural results suggested the eyes have more sophisticated attributes than a simple light detector. This work has provided the framework upon which specific structure to function questions can be explored to advance our understanding of the Photuris firefly larval visual system

The Pagoda Sequence: a Ramble through Linear Complexity, Number Walls, D0L Sequences, Finite State Automata, and Aperiodic Tilings

We review the concept of the number wall as an alternative to the traditional linear complexity profile (LCP), and sketch the relationship to other topics such as linear feedback shift-register (LFSR) and context-free Lindenmayer (D0L) sequences. A remarkable ternary analogue of the Thue-Morse sequence is introduced having deficiency 2 modulo 3, and this property verified via the re-interpretation of the number wall as an aperiodic plane tiling

Network Variability Limits Stimulus-Evoked Spike Timing Precision in Retinal Ganglion Cells

SummaryVisual, auditory, somatosensory, and olfactory stimuli generate temporally precise patterns of action potentials (spikes). It is unclear, however, how the precision of spike generation relates to the pattern and variability of synaptic input elicited by physiological stimuli. We determined how synaptic conductances evoked by light stimuli that activate the rod bipolar pathway control spike generation in three identified types of mouse retinal ganglion cells (RGCs). The relative amplitude, timing, and impact of excitatory and inhibitory input differed dramatically between On and Off RGCs. Spikes evoked by repeated somatic injection of identical light-evoked synaptic conductances were more temporally precise than those evoked by light. However, the precision of spikes evoked by conductances that varied from trial to trial was similar to that of light-evoked spikes. Thus, the rod bipolar pathway modulates different RGCs via unique combinations of synaptic input, and RGC temporal variability reflects variability in the input this circuit provides

Goo - Goo Land

https://digitalcommons.library.umaine.edu/mmb-vp/5276/thumbnail.jp

Goo - Goo Land

https://digitalcommons.library.umaine.edu/mmb-vp/5277/thumbnail.jp

Legumes in Cropping Systems

This book is a contribution to the debate and knowledge for the rebalancing of farming and food using legumes. The main aim is to help people who are involved in developing cropping systems: the decision makers of today and today's students who are the decision makers of tomorrow. It is aimed at all relevant decision makers: farmers, professionals who support innovation in farming, and the policy community in its widest sense. It contains 13 chapters describing various aspects of the use of legumes (including grain and feed legumes) in European cropping systems. Each chapter provides deep insight into the relevant literature to support understanding rather than a comprehensive academic review. The aim is to empower the reader with insights and understanding of the underlying processes that influence cropping system development

Health behavioural theories and their application to women's participation in mammography screening

The most effective method of detecting breast cancer amongst asymptomatic women is by mammography screening. Although, most countries have this preventive measure in place for women within their society; most of these programmes still struggle with women’s attendance. This article discusses four health behavioural theories and models, in relation to mammography screening, including the health belief model, theory of planned behaviour, trans-theoretical model, and the theory of care seeking behaviour that may explain the factors affecting women's participation in mammography screening. In summary, analysis of these theories indicates that the theory of care seeking behaviour has value for exploring the factors affecting women's participation in mammography screening. This is because of its sensitivity to socioeconomic differences that exists amongst women in the society, and that it has a broader construct (such as habit and external factors) compared to the other health behavioural theories

Likelihood Estimation for Block Cipher Keys

In this paper, we give a general framework for the analysis of block ciphers using the statistical technique of likelihood estimation. We show how various recent successful cryptanalyses of block ciphers can be regarded in this framework. By analysing the SAFER block cipher in this framework we expose a cryptographic weakness of that cipher