Temporal Variation in Larval Fish Condition Indices.

A sensitive methodology for the determination of RNA and DNA concentrations was developed which allowed for the quantification of nanogram amounts of both DNA and RNA. The method uses a combination of thiazole orange, a non-specific nucleic acid stain, and the RNA degrading enzyme RNase. Thiazole orange had high fluorescence yield. The fluorescence was additive for combinations of RNA and DNA. The addition of proteinase-K increased the fluorescence of the tissue sample by 100%. Recovery of nucleic acid standards added to tissue extracts yielded $\sim$100% recovery. The method is compatible with assays for protein concentration and electron transport system (ETS) enzyme activity. Menhaden (Brevoortia patronus) larvae and meteorological data were collected for 2 week intervals during the winters months of 1993-1994 and 1994-1995 in an examination of the role of atmospheric frontal passage on larval condition. Three biochemical assays were used to quantify larval condition, RNA:DNA, protein concentration and ETS activity. Each day of collection was categorized in terms of the prevailing atmospheric conditions. The larvae were in good condition and there was no consistent trend in the condition of the larvae through the two spawning season. There was no indication that poor condition larvae were being lost from the population. Larval condition was not strongly affected by water temperature or any meteorological variable. All condition indices were highest during periods of southerly winds associated with the progression of atmospheric cold fronts. The variation in condition indices among the months of collection and between the years of collection can be explained by the frequency of the atmospheric cold fronts. The increase in larval condition in association with the cold fronts is likely a result of the increased encounter rate with prey items due to an increase in wind-generated turbulence. A new morphometric analysis technique based upon the thin-plate spline was examined as a low-cost alternative to the biochemical measures of condition. This method of shape analysis was not successful in identifying the known condition of the larvae. The short-term influence of the atmospheric cold fronts was of insufficient intensity to generate morphological change in the larvae

Assessing Student Orientation to School to Address Low Achievement and Dropping Out

This study contributes to applied and theoretical research for schools and districts by helping inform programs and policies directed at school improvement, raising student achievement, and high school completion. The paper features recent results of ongoing research on student orientation to school that was assessed via a multi-dimensional Student Orientation to School Questionnaire (SOS-Q). The SOS-Q was initially used by a Canadian school district to better understand the reasons for dropping out of school. Since then the project has grown into a multi-organizational collaboration. This study demonstrates persistent associations between student orientation to school, academic achievement, and high school completion and makes the case for integrating valuable non-cognitive components within comprehensive student information and assessment systems.Cette étude contribue à la recherche appliquée et théorique portant sur les écoles et les districts scolaires dans la mesure où elle pourra servir à étayer les programmes et les politiques visant l’amélioration des écoles, le rehaussement du rendement par les élèves et l’achèvement des études secondaires. Cet article présente les résultats récents d’une recherche en cours sur l’adaptation scolaire évaluée par le biais d’un questionnaire pluridimensionnel. Le questionnaire a d’abord servi d’outil pour un district scolaire canadien qui cherchait à mieux comprendre les raisons du décrochage scolaire. Depuis, le projet s’est transformé en collaboration impliquant plusieurs organisations. Cette étude révèle des associations systématiques entre l’adaptation des élèves à l’école, le rendement académique et l’achèvement des études secondaires. Elle milite en faveur de l’intégration de composantes non cognitives importantes au sein des systèmes scolaires d’information et d’évaluation

A qualitative analysis of the need-satisfying experiences of the customers of a niche-restaurant

Tradition dictates that marketing decision-makers remain accurately aligned with the dynamic and vacillating need structures of the target markets they serve. To comply with this caveat, a time-honoured and largely unchallenged philosophy of customer orientation has been applied. Theory further strongly contends that if such a business stance is vigilantly and diligently applied, any firm is bound to gain a competitive edge in the market place. A weakness in the above marketing mindset is the perception that when a spectrum of business elements are orchestrated and focussed on customers, target audience members will automatically be satisfied and return their patronage. This so-called marketing concept has undergone major reevaluations over the past decades, and it is now becoming ever more prevalent to witness varied permutations of new marketing architecture evolving in literature and practice. The unit of analysis selected for this research study is a niche restaurant that flouts many of the rudimentary traditional rules of marketing and iconoclastically succeeds despite all counter-logic. What such organisations have been practicing, albeit unknown to themselves, is a new way of business - a stance that has only recently been taken seriously by academics, writers and marketing professionals. These intuitive marketers are succeeding in niche businesses, despite going against the tide of the ingrained paradigm mindsets of conventional marketing stalwarts. Such niche business people have discovered is that there is more to satisfying consumer needs than simply honing in and understanding what the basic needs of designated audiences are. A growing band of new age marketers have been challenging orthodox marketing philosophy. Tofler, the visionary futurist, alluded to a host of unarticulated psychic consumer needs that would emerge as society drifted into a clinical and dispassionate ‘new’ millennium. In a world geared to instant gratification, fast-paced living and mechanistic social interactions, jaded consumers seek recognition as individuals (Tofler, 1970). They quest for inclusion rather than exclusion. They need a place to feel safe and find solace. Hence, it is now clear that simply attempting to satisfy the fundamental dimensions of consumers’ needs is no longer sufficient. Consumers rather seek the fulfilment of an holistic band of experience dimensions. Increasingly, phrases such as “winning consumer hearts and minds” are entering the vocabulary of marketers on a regular basis. The present vogue is to isolate and then include a range of intangible elements that are embodied in the process of satisfying customers needs. However, despite a growing awareness of the significance of mental-need satisfiers, in the specific domain of this investigation there is sparse evidence in literature of the mechanics of such novel thinking. The study unit is a second generation restaurant where many of the hollowed cornerstones of conventional marketing are inadvertently flouted. Different sets of rules of engagement seem to apply to their customers, who are also their most ardent advocates. A unique philosophy and business ethos also appears to prevail. In the study, the idiosyncratic characteristics which socially and competitively differentiate such a business were identified, explored and expiated. The constituents were then harmonised in an effort to establish what ‘it’ was that magnetically attracted patrons back despite the owner’s unintentional dismissive predisposition towards fundamental theory. As a result of this in-depth qualitative study, an holistic model encompassing all of the dimensions of a dining out experience at a niche restaurant have been proposed. Consequently the pillars upon which a sustained, enduring, loyal staunch customer base can be bed-rocked have been identified. Further, for the study unit, a typology of its diner corpse has been developed. The owners of the establishment under investigation have succeeded to provide an intimate family haven for their patrons. They, and their diners have collectively given strong, descriptive voice to the psychogenic need satisfying elements that have always existed, but to date have been unarticulated and unrecorded. This thesis brings the milieu of the iconoclast niche restaurant marketing practitioner to life

Positive impact of pre-stroke surgery on survival following transient focal ischemia in hypertensive rats

We describe a positive influence of pre-stroke surgery on recovery and survival in a commonly used experimental stroke model. Two groups of male, stroke-prone spontaneously hypertensive rats (SHRSPs) underwent transient middle cerebral artery occlusion (tMCAO). Group 1 underwent the procedure without any prior intervention whilst group 2 had an additional general anaesthetic 6 days prior to tMCAO for a cranial burrhole and durotomy. Post-stroke recovery was assessed using a 32 point neurological deficit score and tapered beam walk and infarct volume determined from haematoxylin–eosin stained sections. In group 2 survival was 92% (n = 12) versus 67% in group 1 (n = 18). In addition, post-tMCAO associated weight loss was significantly reduced in group 2. There was no significant difference between the two groups in experimental outcomes: infarct volume (Group 1 317 ± 18.6 mm<sup>3</sup> versus Group 2 332 ± 20.4 mm<sup>3</sup>), and serial (day 0–14 post-tMCAO) neurological deficit scores and tapered-beam walk test. Drilling a cranial burrhole under general anaesthesia prior to tMCAO in SHRSP reduced mortality and gave rise to infarct volumes and neurological deficits similar to those recorded in surviving Group 1 animals. This methodological refinement has significant implications for animal welfare and group sizes required for intervention studies

DNA Extraction Method Development for Ocular Tissues

Purpose: DNA extraction kits are traditionally developed to work with liquid tissues such as blood, saliva, and swabs, but some have been proposed to work with solid tissues. Somatic variation in cancers can be important for tumor subtyping and treatment guidance, including ocular tumors. Additionally, epigenetic marks such as 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are tissue-specific and change in disease states, particularly evident in diabetic retinopathy and age-related macular degeneration. Commercial DNA extraction kits are available from several vendors, but the various kits have different strengths and weaknesses, and the removal of PCR inhibitors will vary with each kit. This project investigates the yield and purity of DNA from ocular tissues using commercial DNA extraction kits. Methods: Cornea, neural retina, RPE/choroid layer, optic nerve, and capsular bag were collected and aliquoted into 15 mg aliquots. Extractions were performed using the following kits: DNEasy Blood and Tissue Kit (Qiagen;), GeneJET Genomic DNA Purification Kit (ThermoFisher Scientific), Monarch HMW DNA Extraction Kit for Tissue (New England Biosciences), and genomicPrep Mini Spin Kit (Cytiva). DNA was quantified using the Qubit Fluorometer and molecular weight was checked by agarose gel. Several more kits are currently being tested. Results: All four kits yielded high molecular weight DNA (above 20 kbp). The Monarch HMW kit yielded DNA with significantly higher molecular weights. The DNA yields per milligram of tissue were highest using the DNEasy Blood and Tissue Kit for optic nerve, neural retina, and RPE/choroid. The yield was highest for the cornea using the genomicPrep Mini Spin Kit. Only the genomicPrep Mini Spin Kit yielded sufficient DNA for quantification from the capsular bag, and total yields were minimal (600 ng or less). Additional kits are currently being tested, but initial results indicate that several commercial kits will be sufficient for DNA extraction of ocular tissues. Further work is needed to purify epithelial cells and stem cells from the intraocular lens. Conclusions: Of the kits tested, all are sufficient to obtain significant amounts of DNA from all ocular tissues aside from the capsular bag. The Monarch HMW yielded the highest molecular weight, but significantly lower quantities of DNA than the other kits, indicating that it may not be ideal for most purposes. Protocol development for the capsular bag is still underway

Ischemic preconditioning protects against cardiac ischemia reperfusion injury without affecting succinate accumulation or oxidation.

Ischemia-reperfusion (IR) injury occurs when blood supply to an organ is disrupted and then restored, and underlies many disorders, notably myocardial infarction and stroke. While reperfusion of ischemic tissue is essential for survival, it also initiates cell death through generation of mitochondrial reactive oxygen species (ROS). Recent work has revealed a novel pathway underlying ROS production at reperfusion in vivo in which the accumulation of succinate during ischemia and its subsequent rapid oxidation at reperfusion drives ROS production at complex I by reverse electron transport (RET). Pharmacologically inhibiting ischemic succinate accumulation, or slowing succinate metabolism at reperfusion, have been shown to be cardioprotective against IR injury. Here, we determined whether ischemic preconditioning (IPC) contributes to cardioprotection by altering kinetics of succinate accumulation and oxidation during IR. Mice were subjected to a 30-minute occlusion of the left anterior descending coronary artery followed by reperfusion, with or without a protective IPC protocol prior to sustained ischemia. We found that IPC had no effect on ischemic succinate accumulation with both control and IPC mice having profound increases in succinate compared to normoxia. Furthermore, after only 1-minute reperfusion succinate was rapidly metabolised returning to near pre-ischemic levels in both groups. We conclude that IPC does not affect ischemic succinate accumulation, or its oxidation at reperfusion

Selective mitochondrial superoxide generation in vivo is cardioprotective through hormesis

Reactive oxygen species (ROS) have an equivocal role in myocardial ischaemia reperfusion injury. Within the cardiomyocyte, mitochondria are both a major source and target of ROS. We evaluate the effects of a selective, dose-dependent increase in mitochondrial ROS levels on cardiac physiology using the mitochondria-targeted redox cycler MitoParaquat (MitoPQ). Low levels of ROS decrease the susceptibility of neonatal rat ventricular myocytes (NRVMs) to anoxia/reoxygenation injury and also cause profound protection in an in vivo mouse model of ischaemia/reperfusion. However higher doses of MitoPQ resulted in a progressive alteration of intracellular [Ca2+] homeostasis and mitochondrial function in vitro, leading to dysfunction and death at high doses. Our data show that a primary increase in mitochondrial ROS can alter cellular function, and support a hormetic model in which low levels of ROS are cardioprotective while higher levels of ROS are cardiotoxic.The work is supported by an MRC Studentship to JFM and a Wellcome Trust Investigator award to RCH (110158/Z/15/Z), the Leducq Transatlantic Network of Excellence, and the University of Padova Strategico grant (FDL). Part of the study was funded by an MRC Project Grant to TK (MR/P000320/1). Michele Cariello is thanked for help with cyclic voltammetry

A Fourier (k-) space design approach for controllable photonic band and localization states in aperiodic lattices

In this paper we present a systematic study of photonic bandgap engineering using aperiodic lattices (ALs). Up to now ALs have tended to be defined by specific formulae (e.g. Fibonacci, Cantor), and theories have neglected other useful ALs along with the vast majority of non-useful (random) ALs. Here, we present a practical and efficient Fourier space-based general theory to identify all those ALs having useful band properties, which are characterized by well-defined Fourier (i.e. lattice momentum) components. Direct control of field localization comes via control of the Parseval strength competition between the different Fourier components characterizing a lattice. Real-space optimization of ALs tends to be computationally demanding. However, via our Fourier space-based simulated annealing inverse optimization algorithm, we efficiently tailor the relative strength of the AL Fourier components for precise control of photonic band and localization properties.Comment: 25 pages, 4 figure