Standard Textbooks Research Articles

A Comprehensive Review of the Anatomy of the Inferior Mesenteric Artery: Branching Patterns, Variant Anatomy and Clinical Significance

The objective of this review is to describe the normal and variant anatomy of the inferior mesenteric artery (IMA), including a brief overview of the relevant embryology, as well as proposing a classification system of the IMA vasculature, and clinical significance. A systematic review of articles published in Google Scholar and PubMed database using search terms: inferior mesenteric artery anatomy, inferior mesenteric artery variation, inferior mesenteric artery development, mesenteric circulation anatomy and variation, inferior mesenteric artery angiography. This was followed by review of the reference list of relevant publications to reveal publications missed during the initial search. Several standard anatomy and surgery text books were also referred for normal anatomy. The anatomy of the inferior mesenteric system is highly variant, with only a small proportion of anatomical, angiographic or surgical studies providing support for what is traditionally taught to be normal anatomy. Whilst the origin of the inferior mesenteric artery is less variant, the branching into left colic, sigmoidal and superior rectal arteries is variable between individuals in terms of origin of branches, number of branches and the presence or absence of certain branches. Whilst there did not appear to be a common classification system, similarities included three main variants of branching with a colo-sigmoid trunk, recto-sigmoid trunk or common trifurcation. There is a disparity between what is described in anatomical texts as the ‘normal’ IMA, and what is seen in anatomical, radiological and surgical research studies. The variable anatomy of the inferior mesenteric artery and its branches is significant in radiological interpretation and colorectal surgery from both an oncological perspective when considering resection, as well as in colonic ischaemia. A classification system has been introduced with a step-wise approach to the assessment of the IMA anatomy to avoid misleading nomenclature and provide a framework for surgeons to assess the vasculature.

A Note on the Comparison of NPV Profiles of Mutually Exclusive Projects

One of the basic tenets of modern finance is that an asset’s required return depends on that asset’s risk. Hence, a project’s cost of capital should be matched with the riskiness of that project. From this standpoint, one may conclude that the standard textbook treatment of NPV profiles is restricted to the case where the projects being compared have the same risk and, therefore, have the same discount rate. When the same discount rate is inappropriately applied to different projects, the usual comparison of NPV profiles can be misleading. It is when possible differences in project risk and associated cost of capital are explicitly considered, that NPV profiles can become more useful in the comparative evaluation of mutually exclusive projects.

The Bloch correction, key to heavy-ion stopping

The Bloch correction is known as the link between Bethe’s quantum theory of the stopping of charged particles in matter and Bohr’s classical theory. Less well-known and underestimated in the literature, is its role as the link between the energy loss of heavy vs light ions. At the same time, the role of another key parameter, the ion charge, has been unclear until a few years ago, not the least due to the almost universal use of the competing effective-charge concept. We show that proper account of the Bloch correction and the ion charge forms the key to a qualitative and quantitative description of the electronic energy loss of heavy ions. In the standard textbook versions, neither Bohr nor Bethe stopping provide a valid description below the Bragg maximum, since logarithmic dependencies on the velocity cause the stopping cross section to become negative. Although this obstacle can easily be repaired by more accurate evaluation of the underlying integrals, we found the Bloch correction to be more tightly connected with these logarithms than expected. This requires caution in practical applications.

Teaching climate complacency: mainstream economics textbooks and the need for transformation in economics education

ABSTRACT In this paper we ask, what is mainstream economics education conveying to its students? Standard mainstream economics textbooks treat the environment as a specialist issue in addition to standard concerns and based on solutions that conform to those standard concerns. When viewed as socialisation for students this is a major problem. To illustrate the problems we set out key aspects of the standard format, and draw attention to the structure and contents from two well-known textbooks. Standard textbooks convey the impression that the ‘environmental issue’ is appropriately incorporated and exhibit two complacency-creating features. First, fundamental problems (acute global ecological breakdown, biodiversity loss, climate change crisis etc), issues and urgency cannot be adequately conveyed to students within this way of framing economics. Second, specific theory and policy solutions suggest that the problem is well in hand. We illustrate using the theory of negative externalities.

A primer on tissue pH and local anesthetic potency.

The relationship between pH, pKa, and degree of local anesthetic ionization is quantified by the Henderson-Hasselbalch equation. As presented in standard textbooks, the effect of pH on the degree of ionization of any particular local anesthetic is not immediately clear due to the x-axis displaying pH - pKa, which requires conversion to pH, based on the pKa for each local anesthetic, a complex process. We present a graphical solution that clarifies the interrelationships between pH, pKa, and degree of ionization by plotting pKa on the x-axis versus the percentage of unionized local anesthetic on the y-axis. The vertical intercept from the x-axis to the pH curves allows rapid and accurate estimation of the degree of ionization of any local anesthetic of known pKa.

Lawrence E. Boland, Equilibrium Models in Economics. Purposes and Critical Limitations

Equilibrium Models in Economics addresses the limitations of “equilibrium models”, i.e. economics models, in which “equilibrium is a central organising idea” (the quote is from Frank Hahn; 1). Lawrence Boland’s discussion of equilibrium models focuses on the “attainment” of equilibrium: How does a model move from out-of-equilibrium (or “disequilibrium”) positions toward equilibrium? The book starts with an assessment of the “standard textbook equilibrium model” (which is presented by Boland i...

( scientific ) تحليل الكتاب المدرسي للغة العربية في المرحلة الإبتدائية بمدخل العلمي

This study aims to determine appropriateness of Arabic textbooks at 2013 curriculum of Madrasah Ibtidaiyah in the scientific approach published by the Ministry of Religion which adjusted to the standards of the scientific approach and the standard of textbooks have been set. The research method is a description of qualitative method ( not in the form of numbers). The method used to collect data is a documentary method, for the document information researches are using an instrument which called content analysis. The results of the study, books published by the Ministry of Religion are still many errors in arabic language textbooks at the 5th grade Madrasah, both standard textbooks and substances. The various imporvements are needed to be used as textbook materials.

Are textbook lungs really normal? A cadaveric study on the anatomical and clinical importance of variations in the major lung fissures, and the incomplete right horizontal fissure.

The lungs have three main fissures: the right oblique fissure (ROF), right horizontal fissure (RHF), and left oblique fissure (LOF). These can be complete, incomplete or absent; quantifying the degree of completeness of these fissures is novel. Standard textbooks often refer to the fissures as complete, but awareness of variation is essential in thoracic surgery. Fissures in 81 pairs of cadaveric lungs were classified. Oblique fissures were measured from lung hila posteriorly to the lung hila anteriorly; and the RHF measured from the ROF to the anteromedial lung edge. The degree of completeness of fissures was expressed as a percentage of the total projected length were they to be complete. The frequency and location of accessory fissures was noted. LOF were complete in 66/81 (81.5%), incomplete in 13/81 (16.0%) and absent in 2/81 (2.47%); ROF were complete in 52/81 (64.2%), incomplete in 29/81 (35.8%) and never absent; RHF were more variable, complete in 18/81 (22.2%), incomplete in 54/81 (66.7%) and absent in 9/81 (11.1%). LOF and ROF were on average 97.1% and 91.6% complete, respectively, being deficient posteriorly at the lung hila. The RHF on average 69.4% complete, being deficient anteromedially. There were accessory fissures in 10 left and 19 right lungs. This study provides a projection of the anatomy thoracic surgeons may encounter at operation, in particular the variable RHF. This knowledge is essential for optimal outcomes in both benign and oncological procedures influenced by the fissures.

Clinical Pediatric Anesthesia: A Case-Based Handbook

Clinical Pediatric Anesthesia: A Case-Based Handbook

A brief introduction to gauge-invariant dynamical systems

We describe gauge symmetry at the elementary level aiming at undergraduate and first-year graduate theoretical physics students. The formal definition of gauge invariance as a local symmetry of the action is given and further elaborated and interpreted in detail in two physical models, namely, a mechanical system and the prototypical gauge field theory of electrodynamics. The first model, consisting of two interacting particles with gauge symmetry, sets the background and paves the way for the canonical analysis of the electromagnetic field as a constrained system. The Dirac–Bergmann algorithm and the necessity of Dirac brackets for the canonical quantization of constrained systems are discussed within the two models context. The whole analysis is written in a didactical way trying to guide and motivate undergraduate students along an introduction to gauge symmetry. After going through this present brief introduction, the reader should be well prepared to boldly continue their journey through more advanced standard textbooks on the subject.

Explaining the demand and supply model with the cost-benefit rule

This paper provides a simple and intuitive explanation of the demand and supply model based on the cost-benefit rule. This rule states that an action (e.g. to buy or to sell) should be undertaken only if its benefits are greater than its costs. The approach is not novel, but standard introductory textbooks only use it to explain few isolated aspects of the demand and supply model. In this paper the demand and the supply are both fully derived by simply sorting and counting the transactions that pass the cost-benefit rule for buyers and sellers. The emphasis on this rule has two main advantages. First, it makes the model more relatable, as it is more easily applied to everyday concepts and decisions students are familiar with. Second, it provides new students of economics with a clear explanation of how, in general, the discipline of economics approaches the analysis of decisions and behavior.

Notes on reflection and refraction of evanescent plane waves on the boundary between gainy/lossy media

Abstract Reflection and transmission (refraction) of a homogeneous plane wave at the planar boundary of two dielectric media is a well known phenomenon commonly treated in nearly all standard textbooks. Here the analysis of reflection and refraction of evanescent plane waves on the planar boundary between various combinations of lossy, gainy and lossless media is performed. It is shown that by the appropriate choice of the profile of evanescence various effects can take place.

The Anatomical Relationship Between Acupoints of the Face and the Trigeminal Nerve

Objective: Acupuncture continues to gain popularity as a first treatment option for a variety of conditions; however, an in-depth understanding of the relationships between the acupoints and the underlying anatomy of the human body is often unclear. This article updates the anatomical relationship between facial acupoints and the trigeminal nerve (CN V) and contrasts the results against the standard textbook Chinese Acupuncture and Moxibustion. Methods: A literature review, cadaver dissection, and a neuroanatomical stimulation of the CN V was conducted, focusing on the anatomical locations of the acupoints along the CN V on the face and nerve block targets. The results were contrasted against the standard acupoint location and nerve targets described in Chinese Acupuncture and Moxibustion. Results: The present article classifies CN V acupuncture targets according to 4 different types: (1) trunk; (2) bifurcation; (3) branch; and (4) anastomoses. The results of this exploration highlight the specificity with which acupoints are located in relation to the CN V. Areas of high nerve density correspond to several acupoints. Consequently, acupoints overlay closely with CN V branches as they emerge and bifurcate on the face. Conclusions: There is a clear and neuroanatomically relevant relationship between facial acupoints and the CN V.

EFFECTIVENESS OF FLIPPED CLASSROOM LEARNING IN THE ACHIEVEMENT OF COMPUTER SCIENCE AMONG HIGHER SECONDARY SCHOOL STUDENTS

Modern Techniques are introduced in teaching and learning process frequently one such technique is Flipped Classroom learning. Where the pupils are asked to learn the contents given to them at their home from the available sources and they review the topics in their classroom. Since every student collect information from various sources like YouTube, Video lessons, different types of educational apps, Magazines and sources from elders etc. the collection will be excellent to review and collective ideas can help them to learn better than routine blackboard chalk and talk method by doing. So, they learn effectively and their doubts are cleared through discussion with peers in the presence of teacher. The teacher can conclude the teaching learning process by giving extra information left untouched by the students. The researcher is a computer science teacher so she took a lesson from Eleventh Standard Computer Science text book of State board in the 4th Chapter of Volume - I, "Theoretical Concepts of Operating System" and she prepared a video lesson, that video lesson is utilized by the students to learn the contents allotted to them. The Conclusion of her studying, she found that flipped classroom learning is effectively impact in the course content to the students.

Writing Up and Down: The Language of Educational Research

Abstract There is a marked tendency in educational research to marginalise the written word, and to be wary of what I here call its ‘writerliness’: its capacity to go beyond the prosaic and the utilitarian, where meaning is understood largely in terms of the success of language in reflecting reality. I note various symptoms of this in the world of educational research, but especially in standard textbooks of educational research method, where the ambition to eliminate writing is particularly evident. In its second half the paper turns to educational research as the investigation less of causes than of meaning. Here writing—finding the right words—is itself research, rather than a process that is first performed according to various protocols of method and then ‘written up’. I draw on an illuminating discussion of this in Raimond Gaita's Introduction to recent editions of Peter Winch's The Idea of a Social Science and apply it to current debate over discipline in UK schools.

Grossing Issues in Ovarian and Fallopian Tube Pathology

Abstract Ovaries and fallopian tubes are often removed for treatment of various benign and malignant gynecological conditions including prophylactic resections in high-risk patients. Meticulous grossing techniques are essential for staging, prognostication, and accurate diagnosis. We conducted a comprehensive review of published literature on methods for grossing pelvic adnexal specimens, including standard textbooks and grossing manuals, supplemented by a limited review of grossing protocols from academic institutions. This review addresses common issues encountered during the grossing of ovarian and fallopian tube specimens.

Assessment of comorbidities in patients with deranged thyroid hormone levels

Background: There is association of deranged thyroid hormone levels with various co-morbidities. Drugs for comorbidity may interact with each other and affect the outcome of treatment. So, this study was planned to find out comorbidities with deranged thyroid hormone levels and various possible drug interactions.Methods: It was a prospective, observational study carried out at tertiary care hospital from November 2017 to June 2018. Thyroid hormonal levels reports were followed in OPD and online information system facility. Drugs interactions were checked by referring standard pharmacology textbooks, review articles and Medscape drug interaction checker. Approval from the Institutional Ethics Committee was taken before initiation of the study. Patients with deranged thyroid hormone levels were included in the study.Results: Study was conducted in 111 patients of thyroid disorders. Spondylitis, asthma, acne cases were seen in hypothyroid patients whereas hypokalemic periodic paralysis, thyroid ophthalmopathy statistically significantly seen in hyperthyroid patients. Various concurrent medications such as calcium, carbamazepine decreases the effects of levothyroxine. For management of comorbidities various drugs are given which also interact among themselves significantly.Conclusions: Diabetes mellites, obesity, spondylitis, lichen planus were more common in hypothyroidism while comorbidities like hypertension, hypokalemic periodic paralysis, thyroid ophthalmopathy were found to be more in hyperthyroidism. Incidence of drug interactions is found to be more with increased use of medications for comorbidities, so physicians should be careful while prescribing them. Due to drug interactions desired effects of drugs given for thyroid disorders may not be observed.

Discounted Cash Flow Methods in Lease versus Purchase Analysis—A Technical Note

The earlier framework uses the before-tax cost of debt as the discount rate in valuation of lease contracts for the reason that such framework explicitly includes the interest tax credits as a component of each period’s cash flows. The short-cut or modern standard textbook approaches use after-tax cost of debt as the discount rate for the reason that it ignores the interest tax credits. Some existing literatures state the two approaches are equivalent without exploring the reasons analytically. This note provides a mathematical demonstration showing, the two approaches are not equivalent accompanied by numerical examples.

Wikipedia in Vascular Surgery Medical Education: Comparative Study.

BackgroundMedical students commonly refer to Wikipedia as their preferred online resource for medical information. The quality and readability of articles about common vascular disorders on Wikipedia has not been evaluated or compared against a standard textbook of surgery.ObjectiveThe aims of this study were to (1) compare the quality of Wikipedia articles to that of equivalent chapters in a standard undergraduate medical textbook of surgery, (2) identify any errors of omission in either resource, and (3) compare the readability of both resources using validated ease-of-reading and grade-level tools.MethodsUsing the Medical Council of Canada Objectives for the Qualifying Examination, 8 fundamental topics of vascular surgery were chosen. The articles were found on Wikipedia using Wikipedia’s native search engine. The equivalent chapters were identified in Schwartz Principles of Surgery (ninth edition). Medical learners (n=2) assessed each of the texts on their original platforms to independently evaluate readability, quality, and errors of omission. Readability was evaluated with Flesch Reading Ease scores and 5 grade-level scores (Flesch-Kincaid Grade Level, Gunning Fog Index, Coleman-Liau Index, Simple Measure of Gobbledygook Index, and Automated Readability Index), quality was evaluated using the DISCERN instrument, and errors of omission were evaluated using a standardized scoring system that was designed by the authors.ResultsFlesch Reading Ease scores suggested that Wikipedia (mean 30.5; SD 8.4) was significantly easier to read (P=.03) than Schwartz (mean 20.2; SD 9.0). The mean grade level (calculated using all grade-level indices) of the Wikipedia articles (mean 14.2; SD 1.3) was significantly different (P=.02) than the mean grade level of Schwartz (mean 15.9; SD 1.4). The quality of the text was also assessed using the DISCERN instrument and suggested that Schwartz (mean 71.4; SD 3.1) had a significantly higher quality (P=.002) compared to that of Wikipedia (mean 52.9; SD 11.4). Finally, the Wikipedia error of omission rate (mean 12.5; SD 6.8) was higher than that of Schwartz (mean 21.3; SD 1.9) indicating that there were significantly fewer errors of omission in the surgical textbook (P=.008).ConclusionsOnline resources are increasingly easier to access but can vary in quality. Based on this comparison, the authors of this study recommend the use of vascular surgery textbooks as a primary source of learning material because the information within is more consistent in quality and has fewer errors of omission. Wikipedia can be a useful resource for quick reference, particularly because of its ease of reading, but its vascular surgery articles require further development.

EFFECTIVENESS OF BLENDED LEARNING CLASSROOM IN COMPUTER SCIENCE TEACHING AND LEARNING

In recent trends teaching and learning become very interesting due to the innovative methods of teaching using many technologies and practical tools. This study is dealing with new trends in education that can help one to become a modern teacher. Students like the teaching of modern teachers because they can actively participate in the learning process. E-content, Video Lessons and Online teaching and many other tools are used to present the subject innovatively and productively. Blended learning classroom is the latest educational technique that is being adapted in modern classrooms to enhance the learning experience of the students. The researcher is a Computer Science educator and she prepared a video lesson on "Working with Linux - Ubuntu" which is in Volume-I, Unit-I, Chapter 5 of XI Standard Computer Science text book in Tamil Nadu State Board Samacheer Kalvi new syllabus. The conclusion of her study reveals that blended learning classroom has positive impact on XI Std pupil's academic fulfilment of Computer Science.