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Book Review: Grimwood, M and McHanwell, S. (2024) Evidencing Teaching Achievements in Higher Education. Critical Publishing.
No full textBook Review: Grimwood, M and McHanwell, S. (2024) Evidencing Teaching Achievements in Higher Education. Critical Publishing.
Christopher Little
Manchester Metropolitan University
Corresponding author: [email protected]
Organic livestock production
No full textThe development towards a sustainable agriculture has been a main objective of organic agriculture from the beginning (IFOAM, 1978), and a declared objective of the newly applied EC-Regulation (1804/1999) on organic livestock production which provides a clear framework for livestock production. The leading idea is based on the voluntary self-restriction in the use of specific means of production with the objectives to produce food of high quality in an animal appropriate and environmentally friendly manner within a nearly complete nutrient farm organism (Sundrum, 1998). With regard to an environmentally friendly production, organic livestock farming is characterised by:
- System-oriented approach,
- Renunciation of mineral nitrogen, pesticides, growth promoters, and GMO’s,
- Maximum total stocking density of 2 large animal units per ha,
- Restrictions in the amount and quality of bought-in feedstuffs.
In the following, consequences of the framework and the production method are discussed in relation to the environmental issue.
System-oriented approach
Livestock production forms an integral part of agricultural holdings practising organic farming. Different agricultural fields are interrelated into a ‘farm organism’ which is driven by a nearly complete innerfarm nutrient cycle. A strict separation into lines of production is inappropriate to the idea of a nutrient cycle. With regard to nutrient losses, level of reference is the farm as a single unit and not a specific level of process engineering as is commonly used in conventional production. For example, it would be inappropriate to assess the emission of nitrogen in relation to the average milk yield per cow without taking the whole farm that is among others nitrogen losses in relation to fodder growing and distribution of manure into account.
Prevention strategy
The general renunciation of mineral nitrogen, risk materials (like pesticides) and controversially discussed substances (like GMO’s) is part of a prevention strategy, leading to a comparable low input of substances, into the farm and to a minimized output. Reduction of pollution or energy consumption is reached by a systemic and casually related approach, while conventional strategies are often based on technical and management related measures (Kristensen and Halberg, 1997).
To assess nutrient losses on the farm level, the most common methodologies involve using balance sheets of the whole farm. Calculations demonstrate that the systemic effect of organic agriculture in both cattle and pig production has great implication on the nutrient balance and the balance-surplus in relation to the product (Haas, 1995; Halberg et al., 1995; Martinson, 1998; Sundrum & Trangolao, 2000). There is reason for the assumption that the benefit of the system-related approach on minimising pollution are much more effective as compared to management-related factors, such as increasing animal performance per animal per year. For example, reducing nitrogen input of 100 kg N/ha is more than doubly efficient in relation to the balance surplus than increasing average milk yield for 1.000 kg/cow and year (Mejs and Mandersloot, 1993). However, there is a high variability within organic farms in relation to their efforts and their nutrient efficiency.
Dual strategy in relation to nitrogen
In organic livestock production, feeding is primarily based on home-grown feedstuffs, including a high amount of legumes. As a consequence crude protein content in the diet often clearly exceeds the requirements of the animals and nitrogen in the manure is on a high level. In conventional production farmers are asked to reduce nitrogen in the diet in order to reduce nitrogen in the manure. In organic farming, a high level of crude protein in the diet is a very important nitrogen source for the innerfarm nutrient cycle. When trying to utilize this nitrogen source, organic farmers are encouraged simultaneously to minimize nitrogen emission from the manure. Due to the limited nitrogen resource, organic farmers have to find the balance within a dual strategy: increasing nitrogen in the manure and minimizing nitrogen emission form the manure. As nitrogen input in the organic farm is on a low level, organic farms are endowed with a credit in relation to nitrogen losses in the following production process. In the long run, the objective to increase productivity within the framework of organic agriculture goes along with improving management measures to minimize nitrogen emission.
On the other hand, the increase of productivity from a high level as being realised in conventional production leads more or less to a higher efficacy of nitrogen turnover and a reduction in nitrogen losses per cow and milk yield (Kirchgessner et al., 1991). However, there is reason for the assumption that with reference to the conventional farm as a whole, nutrient efficacy will probably decrease due to a reduction in digestibility of feedstuffs and higher demands of bought-in concentrates. Those concentrates increase nutrient input in the farm and cause energy consumption especially due to transport. From these theoretical considerations the question arises whether the efforts to increase productivity will reach or even has already exceeded the marginal utility in relation to environmental effects.
It can be concluded that both, a system oriented approach and a approach on the level of process engineering are needed to proceed in environmentally friendly production. Organic livestock production seems to be in the lead because production starts from a comparable low level of nutrient input
A Mixed-Method Approach for Quantifying Illegal Fishing and Its Impact on an Endangered Fish Species
No full textIllegal harvest is recognized as a widespread problem in natural resource management. The use of multiple methods for quantifying illegal harvest has been widely recommended yet infrequently applied. We used a mixed-method approach to evaluate the extent, charac- ter, and motivations of illegal gillnet fishing in Lake Hovsgol National Park, Mongolia and its impact on the lake’s fish populations, especially that of the endangered endemic Hovsgol grayling (Thymallus nigrescens). Surveys for derelict fishing gear indicate that gillnet fishing is widespread and increasing and that fishers generally use 3–4 cm mesh gillnet. Interviews with resident herders and park rangers suggest that many residents fish for subsistence during the spring grayling spawning migration and that some residents fish commercially year-round. Interviewed herders and rangers generally agree that fish population sizes are decreasing but are divided on the causes and solutions. Biological monitoring indicates that the gillnet mesh sizes used by fishers efficiently target Hovsgol grayling. Of the five species sampled in the monitoring program, only burbot (Lota lota) showed a significant decrease in population abundance from 2009–2013. However, grayling, burbot, and roach (Rutilus ruti- lus) all showed significant declines in average body size, suggesting a negative fishing impact. Data-poor stock assessment methods suggest that the fishing effort equivalent to each resident family fishing 50-m of gillnet 11–15 nights per year would be sufficient to over- exploit the grayling population. Results from the derelict fishing gear survey and interviews suggest that this level of effort is not implausible. Overall, we demonstrate the ability for a mixed-method approach to effectively describe an illegal fishery and suggest that these methods be used to assess illegal fishing and its impacts in other protected areas.Peer reviewe
Teacher formative assessment: the missing link in response to intervention
No full textResponse to Intervention (RtI) focuses on the assessment, intervention, and progress monitoring of student academic performance and social behavior. Despite requiring highly-qualified personnel for successful implementation, the implementation of Rtl has not focused on applying its foundational principles towards promoting teacher effectiveness through assessment, intervention, and progress monitoring of teacher classroom practice. Compounding this problem is the lack of availability of reliable and valid teacher assessments to apply in an Rtl model for teacher professional development. This chapter provides a rationale for applying RtI principles to teacher professional development and how teacher formative assessment can improve educator effectiveness, student learning, and social behaviors. The Classroom Strategies Scale (CSS, Reddy & Dudek, 2014), a new multidimensional assessment of instructional and behavioral management practices is discussed as an example of one promising tool for promoting teachers professional development within an Rtl model. We offer a synthesis of the theory, research, and evidence of reliability and validity of the CSS. The application of teacher formative assessment in job-embedded professional development/coaching models for schools is discussed. Finally, implications for practice and research are outlined.Peer reviewe
Oregon Justice Reinvestment Initiative: return on investment
No full textsubmitted to: Oregon Criminal Justice Commission ; principal investigator: Mauri Matsuda, Ph.D. ; co-investigators: Christopher Campbell, Ph.D., Christopher Dollar, M.S., Mark Leymon, Ph.D., Brian Renauer, Ph.D.This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references (pages 38-39).Funded by: Oregon Criminal Justice Commission.Mode of access: Internet from the Oregon Government Publications Collection.Text in English
Pannexin-1 and P2X7-Receptor Are Required for Apoptotic Osteocytes in Fatigued Bone to Trigger RANKL Production in Neighboring Bystander Osteocytes
No full textOsteocyte apoptosis is required to induce intracortical bone remodeling after microdamage in animal models, but how apoptotic osteocytes signal neighboring “bystander” cells to initiate the remodeling process is unknown. Apoptosis has been shown to open pannexin-1 (Panx1) channels to release adenosine diphosphate (ATP) as a “find me” signal for phagocytic cells. To address whether apoptotic osteocytes use this signaling mechanism, we adapted the rat ulnar fatigue-loading model to reproducibly introduce microdamage into mouse cortical bone and measured subsequent changes in osteocyte apoptosis, receptor activator of NF-kB ligand (RANKL) expression and osteoclastic bone resorption in wild-type (WT; C57Bl/6) mice and in mice genetically deficient in Panx1 (Panx1KO). Mouse ulnar loading produced linear microcracks comparable in number and location to the rat model. WT mice showed increased osteocyte apoptosis and RANKL expression at microdamage sites at 3 days after loading and increased intracortical remodeling and endocortical tunneling at day 14. With fatigue, Panx1KO mice exhibited levels of microdamage and osteocyte apoptosis identical to WT mice. However, they did not upregulate RANKL in bystander osteocytes or initiate resorption. Panx1 interacts with P2X7R in ATP release; thus, we examined P2X7R-deficient mice and WT mice treated with P2X7R antagonist Brilliant Blue G (BBG) to test the possible role of ATP as a find-me signal. P2X7RKO mice failed to upregulate RANKL in osteocytes or induce resorption despite normally elevated osteocyte apoptosis after fatigue loading. Similarly, treatment of fatigued C57Bl/6 mice with BBG mimicked behavior of both Panx1 KO and P2X7RKO mice; BBG had no effect on osteocyte apoptosis in fatigued bone but completely prevented increases in bystander osteocyte RANKL expression and attenuated activation of resorption by more than 50%. These results indicate that activation of Panx1 and P2X7R are required for apoptotic osteocytes in fatigued bone to trigger RANKL production in neighboring bystander osteocytes and implicate ATP as an essential signal mediating this process.Peer reviewe
The protective effect of a diet rich in fish oil in an amphetamine toxicity model of Parkinson’s disease
No full textParkinson’s disease is a neurodegenerative disorder that damages the dopaminergic neurons of the substantia nigra and their axonal projections to the striatum. This cell death results in significant motor deficits that include muscular rigidity, resting tremor, and akinesia. Although there is no known cure for Parkinson’s disease, evidence from epidemiological studies suggests that consumption of fish oil, which is rich in omega-3 polyunsaturated fatty acids (PUFAs), may help to reduce the risk of this debilitating disorder. Furthermore, research using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 6-hydroxydopamine (6-OHDA) models of Parkinson’s disease supports this conclusion. Consequently, this dissertation examined the potential protective effect of fish oil in an amphetamine-toxicity model of Parkinson’s disease. In Experiment 1, mice were administered a diet rich in either corn oil or fish oil for one week and then were treated with either amphetamine or saline. After sacrifice 72 hours later, striatal tissue was assayed for neurochemical content using HPLC. It was determined that fish oil protects against amphetamine-induced depletions of dopamine and its metabolites. Given the role of oxidative stress in amphetamine toxicity, this protection may be a result of the antioxidant properties of fish oil. Experiment 2, in addition to successfully replicating this effect, extended the protective effect of fish oil to behavioral and physiological measures. More specifically, a diet rich in fish oil significantly altered amphetamine’s impact on behaviors including oral dyskinesia, self biting, stereotypy, and backwards walking; it also mitigated amphetamine-induced changes in dermal temperature. These results suggest that fish oil can moderate the elevated dopaminergic activity caused by amphetamine administration. Experiment 3 was designed to examine the time course of protection afforded by the fish oil-rich diet, and it was discovered that the protective effect of fish oil develops between 1 and 3 days of consumption. Experiment 4 was performed to determine if fish oil alters amphetamine-induced increases in oxidative stress and dopamine release. Fish oil did not impact these measures, indicating that other mechanisms may be responsible for the observed protection. Collectively, these findings indicate that the consumption of fish oil offers protection against amphetamine toxicity in a model of Parkinson’s disease.Ph. D.Includes bibliographical referencesIncludes vitaby Christopher M. Medveck
Heritability and Linkage Analysis of Appendicitis Utilizing Age at Onset
No full textAppendicitis usually afflicts the young, but there is a large tail in the distribution of onset age. The genetics of this disease are still not well understood. A heritability analysis and genome wide linkage analysis of a large twin dataset was undertaken. Treating age of onset of appendicitis as a censored survival trait revealed a heritability of 0.21, and found evidence of linkage to Chromosome 1p37.3. Author(s): Christopher Oldmeadow 1 * | Kerrie Mengersen 2 | Nicholas Martin 3 | David L. Duffy
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Introduction
No full textByline: Charles B. Nemeroff, Christopher M. O'Connor Author Affiliation: Atlanta, Ga, and Durham, NC From the Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta; and Duke University Medical Center, Durham, NC Article Note: (footnote) [star] Reprint requests: Charles B. Nemeroff, MD, PhD, Psychiatry and Behavioral Sciences, Emory University School of Medicine,1639 Pierce Drive, Atlanta, GA 30322-4990. E-mail: [email protected], [star][star] Am Heart J 2000;140:S55-6.ProfessionalAcademi
"The Federalist" and the classical foundations of the American Republic
No full textThis paper examines the classical themes and ancient historical examples presented through the Federalist Papers of Alexander Hamilton, James Madison, and John Jay. The Federalist Papers represent a lucid sample of early American political theory, and the ideologies of three prominent founders. The study focuses on the Greco-Roman states within those essays that were deemed analogous or relevant to the American Confederacy under the Articles of Confederation, or were used to promote a new federal union under the Constitution. This paper also analyzes the formation of mixed governance constitutions, a vital construction for the creation of modern nations, as the idea progressed through the classical writers Plato, Aristotle, Polybius, and Cicero. Through this analysis, the influences of the Greek and Roman classics are shown to be a formative element in the formation of the American Republic. By reestablishing and reasserting the Classics into the political ideology of that time, insight into the creation of a new Constitution through the combined insight of the Federalist becomes readily apparent. The first section presents an introduction to the Federalist, and the ratification debates of 1787-88. Section two covers the classical influences to American history. The third section is a brief overview of five current works relating to this scholarship. Section four comprises the analysis of the five sections of the Federalist Papers as outlined by Alexander Hamilton. The final section of this paper investigates the writings of Plato, Aristotle, Polybius and Cicero to discover the evolution and creation of theories of mixed constitutions.M.A.Includes bibliographical referencesIncludes vitaby Christopher M. Broschar
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