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Mueller matrix imaging polarimetry (MMIP) is a promising technique for the textural characterization of biological tissue structures. To reveal the influence of imaging magnification on the robustness of Mueller matrix parameters (MMPs), the spatial scale stability of MMPs was studied. We established a new MMIP detector and derived the mathematical model of the spatial scale stability of MMPs. The biological tissues with well-defined structural components were imaged under different magnifications. Then, we compared and analyzed the textural features of the MMPs in the resulting images. The experimental results match the predictions of the mathematical model in these aspects: (i) magnification exhibits a strong nonlinear effect on the textural contrasts of MMPs images; (ii) higher magnification does not necessarily lead to superior contrast for textural characterization; and (iii) for different biological tissues, MMPs contrasts can be optimized differently, with some showing superior results. This study provides a reference for the experimental design and operation of the MMIP technique and is helpful for improving the characterization ability of MMPs. This article is protected by copyright. All rights reserved.

Most cycads have intimate associations with their insect pollinators that parallel those of well-known flowering plants, such as sexually deceptive orchids and the male wasps and bees they deceive. Despite this, the mistaken belief that cycads are mostly wind-pollinated is still commonly expressed. Perhaps as a consequence, cycad–pollinator systems are rarely exemplified in studies of the role of pollinators in plant evolution and diversification. Although first recognised more than a century ago, specialised associations between cycads and their insect pollinators have been elucidated experimentally only in the past few decades. This review covers the history of understanding pollination in cycads, the advances that have been made since the 1980s using field observations and experiments, and analyses of molecular data from the population to phylum level. We outline areas for future research to address how such interactions might have affected speciation and extinctions. We stress that inclusion of cycads in broader considerations of the role of pollinators in plant diversification is important because they are phylogenetically distant from flowering plants and their pollination systems might have evolved independently of one another. This review is timely because cycads are a globally threatened group that might be vulnerable to co-extinction with pollinator loss.

Objectives/Hypothesis Permanent facial nerve injury is a difficult challenge for both patients and physicians given its potential for debilitating functional, cosmetic, and psychological sequelae. Although current surgical interventions have provided considerable advancements in facial nerve rehabilitation, they often fail to fully address all impairments. We aim to introduce an alternative approach to facial nerve rehabilitation. Study Design Acute experiments in animals with normal facial function. Methods The study included three anesthetized cats. Four facial muscles (levator auris longus, orbicularis oculi, nasalis, and orbicularis oris) were monitored with a standard electromyographic (EMG) facial nerve monitoring system with needle electrodes. The main trunk of the facial nerve was exposed, and a 16-channel penetrating electrode array was placed into the nerve. Electrical current pulses were delivered to each stimulating electrode individually. Elicited EMG voltage outputs were recorded for each muscle. Results Stimulation through individual channels selectively activated restricted nerve populations, resulting in selective contraction of individual muscles. Increasing stimulation current levels resulted in increasing EMG voltage responses. Typically, selective activation of two or more distinct muscles was successfully achieved via a single placement of the multi-channel electrode array by selection of appropriate stimulation channels. Conclusion We have established in the animal model the ability of a penetrating electrode array to selectively stimulate restricted fiber populations within the facial nerve and to selectively elicit contractions in specific muscles and regions of the face. These results show promise for the development of a facial nerve implant system. Level of Evidence N/A.Laryngoscope, 2016 127:460–465, 2017

High starch concentrations in the sporophylls of male cones of five species of cycad and their depletion during their heat-producing phase of development suggest that starch is a major fuel source for thermogenesis in these plants. Carbon- 1 3/carbon- 12 ratio analyses of respired C02, starch, and lipids in a male cone of one of these species, Macrozamia moorei F. Muell., indicate that although starch is a major contributor to respiration, lipids are also an important respiratory substrate. THERMOGENESIS, although uncommon in plants in general, has been shown to occur in the flowers or inflorescences of diverse types of plants, including many aroids (Meeuse, 1975), the water lily Victoria sp. (Meeuse, 1975), some palms (Schroeder, 1978), and many species of

A wind and insect exclusion pollination experiment was conducted in a wild population of the cycad Zamia pumila L. in Florida. Cones from which insects but not wind were excluded produced no viable seeds, while cones from which wind but not insects were excluded produced abundant viable seeds. Two beetle species have been identified which may be effecting pollination. Adults and larvae of both beetles are found abundantly on the male cones, and adults of both species and larvae of one species are found occasionally on female cones. Z. pumila produces sugar and amino acid-rich micropyle droplets which may serve as pollinator rewards. Mimicry of resource-rich male cones by female cones and the use of cones as refuges between mating and feeding bouts may account for beetle movement from male to female cones.