bluuebunny/crossref_metadata_2025 huggingface dataset:
La protesta social en América Latina: una aproximación a su fisonomía a propósito de los estallidos sociales de 2019
Authors: Castro Riaño Luis Carlos
Published: December 2020

Durante 2019 se precipitó una ola de estallidos sociales en varios países de América Latina, buena parte de ellos en simultáneo. ¿Qué tienen en común unos y otros desde el punto de vista de las acciones de protesta que implican? En este trabajo me propongo responder a este interrogante considerando las movilizaciones de Haití, Ecuador, Puerto Rico, Bolivia, Chile y Colombia. El supuesto general es que pese a las diferencias contextuales y circunstanciales las dinámicas se reproducen a razón de los motivos y procesos. El análisis se basa en los informes periodísticos de diferentes medios y se apoya en presupuestos de la teoría de la movilización social, de la ciencia política y de la filosofía. El objetivo es elaborar una explicación breve, mediata y actual, de la protesta social en la región, dada su vigencia.
Habitar el hospital en tiempos de pandemia. Historias profesionales de trabajadoras/es sociales en la primera línea de intervención en salud
Authors: Duboy-Luengo Mitzi , Muñoz Arce Gianinna
Published: December 2020

La llegada del COVID-19 a Chile en marzo 2020 ha irrumpido de manera significativa en el ejercicio profesional de las/os trabajadores sociales. En este artículo discutimos desde una perspectiva histórica y contextualizada los desafíos que el trabajo social en salud –específicamente, el trabajo social que se desarrolla en hospitales– enfrenta en este contexto. Se analizan críticamente las orientaciones de política que lo guían y las transformaciones que las/os trabajadores sociales experiencian en su quehacer cotidiano en este ámbito de ejercicio profesional.
Fracaso escolar y abandono educativo temprano. Las escuelas de segunda oportunidad como alternativa
Authors: Arredondo Quijada Rafael , Vizcaíno Martínez Débora
Published: December 2020

El abandono educativo temprano y el fracaso escolar son de las mayores problemáticas educativas que viene enfrentando España en las últimas décadas. Así se presenta un estudio cuantitativo, a través de un cuestionario elaborado exprofeso que ha sido contestado por 229 personas con estas características, en el que entre otras cuestiones se recoge que es la desmotivación el principal elemento que los llevó a no continuar con la formación, siendo el deseo de una mejora personal lo que les ha vuelto hacer retomar los estudios.
Levantamento do patrimônio geológico na “APA da Escarpa Devoniana” em Ponta Grossa, Sul do Brasil
Authors: Folmann Maysa
Published: December 2020

This paper presents a geological heritage survey of the ‘Environmental Protection Area (EPA) of the Devonian Escarpment’ within the boundaries of Ponta Grossa (Southern Brazil), a region of notable geodiversity where socio-environmental conflicts are aggravated. The EPA is a conservation unit that embraces part of the Campos Gerais do Paraná, a rich geodiversity area that holds the last remnants of natural grasslands of the region. Consisting of the primordial stage of a geoconservation strategy, the survey for the inventory becomes an important tool to affect the geoheritage protection. Sixty geological interest sites are presented with their main features, use recommendations, and were classified in geological thematic categories. These actions can guide the next steps for geoconservation of this special area.
The Moderating Effect of Environmental Turbulence on the Strategic Agility-Performance Relationship: Empirical Evidence from Lagos State, Nigeria
Authors: Arokodare M. A.
Published: December 2020

Scholars in strategic management argued that strategic agility measures do enhance firm performance and mitigate environmental turbulence risks. This study therefore examined the moderating effect of environmental turbulence on the relationship between strategic agility and performance of oil and gas marketing companies in Lagos State, Nigeria. Population of the study was 515 managers of major oil and gas marketing companies in Lagos State. Cross-sectional survey research design was adopted with total enumeration. The research instrument was found reliable and valid with Cronbach’s alpha and KMO greater than 0.7 and 0.5 respectively. The data was analyzed using descriptive statistics, Pearson correlation, and multiple and hierarchical regression methods of analyses. Findings revealed that among oil and gas marketing companies in Lagos State, Nigeria, there was positive and significant relationship between strategic agility and performance; strategic agility had positive and significant effect on performance while environmental turbulence significantly moderated the relationship between strategic agility and performance. The study concluded that strategic agility affected and related with firm performance and also environmental turbulence moderated the relationship between strategic agility and performance of oil and gas marketing companies in Lagos State, Nigeria. Therefore, it is recommended that oil and gas marketing companies in Nigeria should fully and dynamically embrace strategic agility practices and continuously develop their capabilities for proper and timely sensing of and responding to changes in their business environment in order to improve their performance over their competitors. Limitations of the study and areas for future research were highlighted.
Human Resource Management from a Justice-Based Perspective
Authors: Masood Qureshi Tahir , Absuweilem Mohemmed , Alkhateeb Shareefa Reda , Anderson Verl , Caldwell Cam
Published: December 2020

It is axiomatic to acknowledge that the Human Resource Management (HRM) function plays a vital ethically-based role in honoring duties owed to organization employees and other stakeholders. Incorporating the research of the University of Michigan ethics expert, LaRue Hosmer, this paper identifies nine qualities associated with organizational justice as they relate to seven important HRM responsibilities. This paper then offers five guidelines for Human Resource Professionals to consider in honoring their justice-related obligations to those whom they serve.
Diagnosis and Management of Traumatic Anterior Shoulder Instability
Authors: Provencher Matthew T. , Midtgaard Kaare S. , Owens Brett D. , Tokish John M.
Published: December 2020

Anterior shoulder instability is the most common form of shoulder instability and is usually because of a traumatic injury. Careful patient selection is key to a favorable outcome. Primary shoulder stabilization should be considered for patients with high risk of recurrence or for elite athletes. Soft-tissue injury to the labrum, capsule, glenohumeral ligament, and rotator cuff influence the outcome. Glenoid bone loss (GBL) and type of bone loss (on-track/off-track) are important factors when recommending treatment strategy. Identification and management of concomitant injuries are paramount. The physician should consider three-dimensional CT reconstructions and magnetic resonance arthrography when concomitant injury is suspected. Good results can be expected after Bankart repair in on-track Hill-Sachs lesions (HSLs) with GBL < 13.5%. Bankart repair without adjunct procedures is not recommended in off-track HSLs, regardless of the size of GBL. If GBL is 13.5% to 25% but on-track, adjunct procedures to Bankart repair should be considered (remplissage and inferior capsular shift). Bone block transfer is recommended when GBL > 20% to 25% or when the HSL is off-track. Fresh tibia allograft or lilac crest autograft are good treatment options after failed bone block procedure.
Management of Partial Tears of the Anterior Cruciate Ligament: A Review of the Anatomy, Diagnosis, and Treatment
Authors: Stone Austin V. , Marx Sean , Conley Caitlin W.
Published: December 2020

Partial anterior cruciate ligament (ACL) tears comprise an estimated 10% to 27% of isolated ACL injuries. Partial ACL tears may be challenging to clinically diagnose. We reviewed relevant studies focusing on the anatomy, diagnosis, imaging, and treatment of a partial injury with the goal of providing guidance to clinicians. Although a comprehensive patient history, thorough clinical examination, and imaging studies are helpful in arriving at a diagnosis, the benchmark for diagnosis remains visualization and examination of the ACL at the time of knee arthroscopy. Currently, limited data exist about the long-term outcomes of nonsurgical treatment. Some studies demonstrate that younger, active patients have the risk of progressing to a complete ACL rupture with conservative treatment. The decision to proceed with surgery is based on careful history and physical examination findings that suggest either a “functional” or “nonfunctional” ACL. Surgical treatment consists of augmenting the intact bundle with a selective bundle reconstruction versus a traditional ACL reconstruction. Selective bundle reconstruction has limited data available but is an option. The best evidence supports traditional ACL reconstruction for the surgical management of patients with documented nonfunctional partial tears of the ACL.
Obesity Is Preferentially Associated With Patellofemoral Compartment Wear: A Magnetic Resonance Imaging Assessment
Authors: Du Jerry Y. , Sivasundaram Lakshmanan , Trivedi Nikunj N. , Voos James E. , Victoroff Brian N.
Published: December 2020

Background:

A well-known association exists between obesity and knee osteoarthritis (OA) for both incidence and progression of the disease. However, the cartilage wear patterns in OA associated with obesity are less well studied.

Methods:

The OA initiative, a prospective sample of 4,796 patients, was used for this study. After the application of inclusion and exclusion criteria, patients were stratified into increasing body mass index (BMI) cohorts (BMI < 25, 25 ≤ BMI < 30, 30 ≤ BMI < 40, and 40 ≤ BMI). Knee MRIs were assessed using the semiquantitative MRI Osteoarthritis Knee Score scores. Patellofemoral (PF), medial, and lateral compartment cartilage scores were compared among BMI cohorts, controlling for confounders using linear regression models.

Results:

In total, 2,006 patients were present in our cohort, 773 men (38.5%) and 1,233 women (61.5%); the mean age was 61.7 ± 8.9 years. Increasing BMI was independently associated with increasing grades of PF wear for both right and left knees in the lateral patella facet (right knee β: 0.208, 95% confidence interval [CI]: 0.128 to 0.288, P < 0.001, left knee β: 0.147, 95% CI: 0.056 to 0.237, P = 0.002), medial femoral trochlea (right knee β: 0.135, 95% CI: 0.065 to 0.204, P < 0.001, left knee β: 0.142, 95% CI: 0.063 to 0.221, P < 0.001), and lateral femoral trochlea (right knee β: 0.163, 95% CI: 0.093 to 0.232, P < 0.001, left knee β: 0.147, 95% CI: 0.067 to 0.226, P < 0.001). For the right knee, increasing BMI was associated with medial compartment wear in the posterior femoral area (β: 0.070, 95% CI: 0.015 to 0.126, P = 0.013) and lateral compartment wear in the central tibial area (β: 0.070, 95% CI: 0.002 to 0.138, P = 0.045). For the left knee, increasing BMI was associated with medial compartment wear in the central femoral area (β: 0.093, 95% CI: 0.016 to 0.171, P = 0.018).

Discussion:

Obesity is preferentially associated with increasing cartilage wear in the PF compartment in comparison to the tibiofemoral compartment. Physical therapy and exercise programs that promote weight loss should be modified to decrease forces on the PF joint.
Offset in Reverse Shoulder Arthroplasty: Where, When, and How Much
Authors: Wright Melissa A. , Murthi Anand M.
Published: December 2020

Since the advent of Paul Grammont medialized reverse shoulder prosthesis in the 1980s, shoulder surgeons have had a reliable option for treating glenohumeral joint disease in the rotator cuff–deficient shoulder. However, the prosthesis is not without complications, including scapular notching, instability, and limited rotational motion. Implants have been modified from the original design in an effort to reduce the risk of these complications. Increasing the offset, or lateralization, of the glenosphere may reduce the rate of scapular notching, reduce impingement, increase stability, and improve rotational motion. However, a more lateralized glenosphere could lead to baseplate loosening, decreased deltoid efficiency, and increased risk of acromial fracture. Increasing the offset on the humeral side, rather than the glenosphere side, may be able to reduce the rate of scapular notching and improve rotational motion without an increased risk of baseplate loosening. Humeral lateralization also improves tension of the rotator cuff and maintains good deltoid efficiency. However, humeral lateralization provides little stability benefit, and acromial fracture remains a risk. Ultimately, the surgeon must be familiar with the implants he or she is using and the options for both glenosphere and humeral lateralization to ensure that risks and benefits can be weighed for each patient.
A Simple, Stepwise, Outside-in Technique for Lateral Retinacular Release for Management of Patellar Maltracking During Total Knee Arthroplasty
Authors: Maniar Adit R. , Maniar Rajesh N.
Published: December 2020

Lateral retinacular release is done to correct patellar maltracking in total knee arthroplasty. The inside-out technique is widely used but has associated risks. Our video describes a simple outside-in technique, done stepwise, and titrated according to the grade of maltracking that maximizes preservation of the superior lateral geniculate artery and preserves the synovium, avoiding complications such as hematoma formation, skin tenting, and wound discolouration. The technique is also effective in all severities of maltracking and with all types of implants.
Lumbar Spine Fusion Before Revision Total Hip Arthroplasty Is Associated With Increased Dislocation Rates
Authors: Klemt Christian , Padmanabha Anand , Tirumala Venkatsaiakhil , Walker Paul , Smith Evan J. , Kwon Young-Min
Published: December 2020

Background:

The aim of this study was to determine whether timing of lumbar spinal fusion (LSF) before revision total hip arthroplasty (THA) would impact dislocation and rerevision rates.

Methods:

This retrospective analysis includes a total of 505 patients who underwent revision THA with concomitant diagnosis of degenerative lumbar spinal stenosis with spondylolisthesis. Patients were stratified into the following two cohorts: (1) 328 patients who underwent revision THA with previous LSF and (2) 177 patients who underwent revision THA, followed by LSF. Postoperative complications including dislocation and rerevision rates were evaluated.

Results:

Patients who underwent revision THA with previous LSF demonstrated significantly higher dislocation rates and rerevision rates compared with patients who underwent revision THA, followed by LSF, at the 1-year follow-up (6.7% versus 5.1%, P < 0.01; 8.5% versus 7.0%, P = 0.02). Patients who underwent revision THA, followed by LSF within 1 year demonstrated significantly higher dislocation and rerevision rates (5.6% versus 4.1%; 7.6% versus 6.4%).

Discussion:

This study demonstrates that patients who underwent revision THA with previous LSF demonstrated notably higher dislocation rates and rerevision rates compared with patients who underwent revision THA, followed by LSF, with the greater the intervals between revision THA and LSF, the lower the postoperative dislocation rates and rerevision rates.
Current Concepts in Pediatric Septic Arthritis
Authors: Erkilinc Mehmet , Gilmore Allison , Weber Morgan , Mistovich R. Justin
Published: December 2020

Septic arthritis continues to present challenges regarding the clinical diagnosis, workup, and definitive management. Urgent management is essential, so treating surgeons must efficiently work through differential diagnoses, identify concomitant infections, and do a timely irrigation and débridement. The incidence of methicillin-resistant Staphylococcus aureus is increasing, typically resulting in a more rapid progression of symptoms with more severe clinical presentation. The diagnostic utility of MRI has resulted in improved detection of concomitant septic arthritis and osteomyelitis, although MRI must not substantially delay definitive management. Early diagnosis followed by urgent irrigation and débridement and antibiotic therapy are essential for satisfactory long-term outcomes. Antibiotics should not be administered until blood cultures and arthrocentesis fluid are obtained, except in rare cases of a septic or toxic patient. Once cultures are obtained, empiric antibiotic therapy should commence and provide coverage for the most likely pathogens, given the patient's age. Laboratory markers, especially C-reactive protein, should be followed until normalization and correlate with resolution of clinical symptoms. Definitive antibiotic selection should be shared with a pediatric infectious disease specialist, who can help guide the duration of treatment.
Opioid Prescription After Carpal Tunnel Release Is Declining Independent of State Laws
Authors: Cunningham Daniel J. , Saltzman Eliana B. , Lorenzana Daniel J. , Klifto Christopher S. , Richard Marc J. , Pidgeon Tyler S.
Published: December 2020

Background:

The opioid misuse crisis focused attention on opioid overprescribing prompting legislation, limiting prescribing. The purpose of this study was to evaluate of opioid filling surrounding carpal tunnel release (CTR) with the hypothesis that filling has decreased in response to state legislation.

Methods:

This is a retrospective, observational study of initial discharge, 30-day, 90-day, and 1-year cumulative opioid filling after CTR in a commercial insurance database between 2010 and 2018. All patients aged 18 and older undergoing CTR and with active insurance status for 6 months preoperative through 30 days, 90 days, and 1 year postoperative were considered for inclusion. Patients undergoing same-day distal radius fracture fixation were excluded. Initial and cumulative perioperative patient, state, and year-level opioid filling rates and volumes in oxycodone 5 mg equivalents (oxycodone 5-mg pills) were evaluated.

Results:

Patients filled mean volumes of 33, 72, and 144 oxycodone 5-mg pills in the initial prescription, by 90 days post-op and by 1 year post-op, respectively. First prescription opioid filling volume (35 oxycodone 5-mg pills 2010 and 27 oxycodone 5-mg pills 2018, P < 0.001) and cumulative 90-day filling (96 oxycodone 5-mg pills 2010 and 56 oxycodone 5-mg pills 2018, P < 0.001) have decreased significantly from 2010 to 2018. Ten of 24 (41.7%) of states with opioid-limiting legislation had large (>5 oxycodone 5-mg pills), notable reductions in initial opioid filling volume after legislation. Five of 13 (38.5%) states without opioid-limiting legislation had similar reductions during the study period. Thirteen of 24 (54.2%) states with opioid-limiting legislation had large, notable reductions in 90-day opioid filling volume after legislation. Six of 13 (46.2%) states without opioid-limiting legislation had similar reductions during the study period.

Conclusion:

Initial and cumulative opioid filling surrounding CTR has decreased notably since 2010. However, opioid legislation did not result in substantial changes in rates of large, notable reductions in state-specific opioid prescribing.
Tranexamic Acid in Patients With Cancer Undergoing Endoprosthetic Reconstruction: A Cost Analysis
Authors: Haase Douglas R. , Kimbrel Brandon , Bombardier Brenden , Templeton Kimberly J. , Rosenthal Howard G. , Sweeney Kyle R.
Published: December 2020

Introduction:

Tranexamic acid (TXA) decreases blood loss, perioperative transfusion rates, and cost in total hip and total knee arthroplasty. In a previous study, topical TXA decreased both perioperative blood loss and transfusions in patients undergoing resection of aggressive bone tumors and endoprosthetic reconstruction. The purpose of this study was to explore the cost effectiveness of TXA in patients undergoing resection of an aggressive bone tumor and endoprosthetic reconstruction, assessing transfusion cost, TXA administration cost, postoperative hospitalization cost, posthospital disposition, and 30-day readmissions.

Methods:

This study included 126 patients who underwent resection of an aggressive bone tumor and endoprosthetic resection at a single academic medical center; 61 patients in the TXA cohort and 65 patients in the non-TXA cohort. The cost of 1 unit of packed red blood cells, not including administration or complications, was estimated at our institution. The cost of hospitalization was estimated for lodging and basic care. The cost of TXA was $55 per patient. Patients were followed up for 30 days to identify hospital readmissions.

Results:

Patients in the TXA cohort experienced a TXA and blood transfusion cost reduction of $155.88 per patient (P = 0.007). Proximal femur replacement patients experienced a $282.05 transfusion cost reduction (P = 0.008), whereas distal femur replacement patients only experienced a transfusion cost reduction of $32.64 (P = 0.43). An average hospital admission cost reduction of $5,072.23 per patient (P < 0.001) was associated with TXA use. Proximal femur replacement patients who received TXA experienced a hospital cost reduction of $5,728.38 (P < 0.001), whereas distal femur replacement patients experienced a reduction of $3,724.90 (P = 0.01). No differences between the cohorts were identified in discharge to home (P = 0.37) or readmissions (P = 0.77).

Discussion:

TXA administration is cost effective in patients undergoing resection of an aggressive bone tumor and endoprosthetic reconstruction through reducing both perioperative transfusion rates and postoperative hospitalization.

Level of evidence:

III—Retrospective Cohort Study
Econometrics Analysis of the Relationship between Climate Change and Economic Growth in Selected West African Countries
Authors: Ceesay Ebrima K. , Oladejo Hafeez O. , Abokye Prince , Ugbor Ogechi N.
Published: December 2020

Linkages between Climate Change, Economic Growth and Poverty Reduction have become increasingly popular in local and international communities. This is due to the fact that we are currently facing pressing issues about climate change and poverty reduction effects in our planet. In this paper an empirical testing of the effects of Climate Change, Economic Growth and Poverty Reduction was carried out. Panel estimation methods of fixed effect, random effect, and panel unit root test-fisher type with trend and constant were applied. From the results, shows that economic growth has a negative and highly significant effect on the growth of poverty in the selected West African countries. Using growth rate of economics as dependent variable, the result shows that growth of poverty is highly significant. The population living in rural areas is significant with growth of poverty and highly significant with growth of food security. The policy recommendation is that the government of the west African countries should put in place strategies to reduce poverty, climate change effects on economics growth by following measures; to have strong institution and avoidance of corruption.Such strategies contain to counter climate change effects and increase the resilience of the economy, society and country in general.
Oral Versus Intramuscular Ondansetron for Reducing Vomiting in Children with Acute Gastroenteritis: A Single-Blind Randomized Clinical Trial
Authors: Eftekhari Kambiz , Mohammadpour Sahar , Shahgholi Elham , Shabani Mirzaee Hosein , Vigeh Mohsen , Malekian Taghi Armen
Published: December 2020

Background: Acute gastroenteritis is one of the most common diseases in children with a high rate of nausea and vomiting. Drugs such as ondansetron are used to treat vomiting. Objectives: The aim of the study was to compare the success rate of oral vs intramuscular ondansetron to reduce vomiting in children with acute gastroenteritis. Methods: A single-blind randomized clinical trial study was conducted on 100 children with acute gastroenteritis. Two groups of patients were created; one group received an intramuscular injection of ondansetron and the other received oral ondansetron. The vomiting rate, hospitalization, and side effects were evaluated 30 minutes, 4, and 48 hours after drug administration. Results: Fifty-nine (59%) participants were boys. The mean age of the patients was 3.07 ± 2.20 years. There were no significant differences between the groups in terms of age, weight, and rate of vomiting before the treatment was launched. No significant difference between the drug administration route and the outcome of vomiting during the first half, 4, and 48 hours after receiving the drug was found either. Conclusions: The study showed that the success rate of oral ondansetron did not vary significantly compared to intramuscular injection in terms of reducing the vomiting rate in children with acute gastroenteritis.
Effectiveness of Spiritual Therapy on Depression, Anxiety, and Stress in Hemodialysis Patients
Authors: Moodi Vihan , Arian Anahita , Moodi Jalil Reza , Dastjerdi Reza
Published: December 2020

Background: The most important psychological problems of dialysis patients are anxiety, depression, and stress. These psychological problems cause different consequences for the patients. ‎Therefore, it seems necessary to use strategies to reduce the psychological problems in hemodialysis ‎patients. Objectives: This study was conducted to evaluate the effectiveness of spiritual therapy on depression, anxiety, and stress in hemodialysis patients referred to the dialysis ward of special diseases center of Birjand in 2019 - 2020. Methods: In this semi-experimental study, 70 patients with chronic kidney disease (CKD) under hemodialysis referred to the dialysis ward of special diseases center of Birjand in 2019 - 2020 were selected by available sampling method and randomized into two experimental groups (35 patients) and control (35 patients). The patients in the experimental group received eight sessions of 60-minute (one session per week) of spiritual intervention therapy, and the control group received no spiritual intervention. Data collection tools were a form of demographic profile and Lovibond SH and Lovibond PF (1995) questionnaire. Data were analyzed using SPSS 26 statistical software, and Fisher’s exact test, chi-square test, independent t-test, repeated measures ANOVA, Bonferroni post hoc test at a significance level of P < 0.05. Results: In this study, 68 patients were ‎examined in two experimental (33 patients) and control (35 patients) groups.‎ The mean score of depression, anxiety, and stress before the intervention in patients in the ‎experimental and control groups was not significantly different ‎(‎P‎ =‎ 0.61‎)‎, but immediately and three ‎months after the intervention in patients in the experiment group was significantly lower than the ‎control group (P < 0.001).‎ Conclusions: Based on the results of the present study, it can be said that spiritual therapy is considered an effective solution for reducing depression, anxiety, and stress in hemodialysis patients.
Three Probable Pediatrics COVID-19 Cases with Kawasaki-like Disease: A Case Series with Fallow-up
Authors: Rafiei Tabatabaei Sedigheh , Karimi Abdollah , Rahimi Hamid , Armin Shahnaz , Fahimzad Seyed Alireza , Mansour Ghanaie Roxana , Dehghan Bahar , Kazemiaghdam Maryam , Alinezhad Marzieh , Saleh Rana , Saeidi Shima , Sharifi Narges , Ramezani Nezhad Davood , Alibeik Mina , Pourmoghaddas Zahra
Published: December 2020

: The first case of Kawasaki-like disease in children infected with COVID-19 was reported in a preprint case report. In the present case series, three pediatric probable cases with COVID-19, who presented signs and symptoms of Kawasaki-like syndrome, and their three-month follow-up are provided.
A Conceptual Model for Solving Percent Problems
Authors: Bennett Albert B. , Nelson L. Ted
Published: December 2020

Applications of percents are often taught by solving proportions that require variables and some familiarity with algebra. Such formal approaches to teaching percent have not been successful for many junior high and high school students (Wiebe 1986). This article present an alternative method that focuses on the basic concept of percent, that of “parts per hundred.” A 10 × 10 grid, which is a common model for visualizing percents, is extended in the following examples to solve various types of percent problems. This model offers a means of representing the given information as well as suggesting different approaches for finding a solution.
Choice and Chance in Life: The Game of “Skunk”
Authors: Brutlag Dan
Published: December 2020

Every day each of us must make choices like those described above. The choices we make are based on the chance that certain events might occur. We informally estimate the probabilities for events by using a variety of methods: looking at statistical information, using past experiences, asking other people's opinions, performing experiments, and using mathematical theories. Once the probability for an event has been estimated, we can examine the consequences of the event and make an informed decision about what to do.
Connecting Research To Teaching: Reflections on Mathematics Education Research over the Twenty-Five Years of JRME
Authors: Lambdin Diana V. , Kloosterman Peter , Johnson Martin
Published: December 2020

How well do you think your students would do on the following problem? “An army bus holds 36 soldiers. If 1,128 soldiers are being bused to their training site, how many buses are needed?” Only 24 percent of a national sample of thirteen-year-olds answered the question correctly (Silver, Shapiro, and Deutsch 1993). Students commonly erred by giving such non-whole number answers as 31 1/3, 31.33, or 31 R 12. To obtain the correel, whole-number answer to this question, students must make sense of the problem, realizing that an additional bus or some other method of conveyance will be needed to transport the “leftover” soldiers. Researchers interested in studying the extent to which students disassociate sense-making from school mathematic have conducted careful analyses of students' solutions to this problem and a number of related problems (see. e.g., Silver, Shapiro, and Deutsch [1993]).
Mathematics Investigator
Authors: Lancaster Ron
Published: December 2020

This article was written to celebrate the fortieth anniversary of the New York City subway token. This anniversary was worth noting because in the not-too-distant future the token is going to be replaced by a plastic fare card. The article is excerpted here, along with several questions for students to ponder.
On My Mind: Scores and Grades: What Are the Problems? What Are the Alternatives?
Authors: Zawojewski Judith S. , Lesh Richard
Published: December 2020

As teachers, we get very enthusiastic when we see the products of students who have been investigating mathematics over extended periods. We are fascinated by the variety of powerful ways in which students solve problems. We enjoy conversations with other teachers about how students' work on performance tasks guides their choices for subsequent classroom experiences. We are pleased that innovative types of perfonnance tasks are being included in systematic assessments of students' performance. However, when we are asked to use a letter grade or numerical score to describe the performance of students on these tasks, our enthusiasm fades. The numbers are so easily and readily used to sort students into “talented” and “not so talented” categoties and not so easily or readily used to identify and nurture the different types of mathematical talents that individuals may possess. We have three major concems with the use of single-value indicators to desctibe a student's abilities in mathematics.
Having Fun with Baseball Statistics
Authors: Quinn Robert J.
Published: December 2020

How often have middle school teachers had to ask students to put away their baseball cards? The lesson described in this article capitalizes on students' interest in sports while providing valuable instruction on a variety of appropriate mathematical topics. Specifically, this lesson meets the recommendations of the NCTM's Curriculum and Evaluation Standards for School Mathematics (1989) by integrating the study of fractions, decimals, percents, rounding, Cartesian coordinates, probability, and statistics in a cooperative setting that allows students to have fun as they learn.
Middle-Grades Geometry Activities
Authors: Maupin Sue
Published: December 2020

Several years ago, when illinois issued its manuals describing the state's learning objectives in mathematics, one school district spent several months examining the mathematics curriculum from kindergarten through the twelfth grade. District goals were written by a committee, condensed to state goals, and submitted to the state as a learning-assessment plan. In the process, deficiencies in the district's curriculum were uncovered. A main deficiency concerned the amount and type of geometry taught in the middle grades.
Translating Number Words into the Language of Mathematics
Authors: Kliman Marlene , Janssen Susan
Published: December 2020

In a sixth-grade mathematics class, students are poring over charts of English and French number words (see figs. 1 and 2). Tasha and Rosa, neither of whom speak French, are engaged in comparing English and French words for multiples of 10 up to 100.
Mathematics Investigator: Pet Owners: Do the Right Thing
Authors: Turner Lionel
Published: December 2020

On any given day, 10,000 human beings are born in the United States. But on that same day, 70,000 puppies and kittens are also born. It is no surprise that too few homes are waiting for too many dogs and cats.
The Thinking of Students: My Application of the Pythagorean Theorem
Authors: Pollack Paul
Published: December 2020

One of my seventh-grade-algebra students, Paul Pollack, shared a discovery he had made. We had finished a unit of study on the Pythagorean theorem, including the Pythagorean triples. Paul noticed that in several triples, the hypotenuse was equal to one of the legs plus 1. For example, 3-4-5, 5-12-13, and 7-24-25 triples have two sides whose values are consecutive integers. Paul was intrigued and developed a pattern to derive triples wherein the hypotenuse and one leg differ by 1, or, for that matter, by any desired quantity. Note that these “triples” often take a little finagling to result in integers (e.g., in example 2). He found thallhe lengths of the three sides of which two are consecutive integers would fit the pattern
Assessment: Describing Student Performance Qualitatively
Authors: Cai Jinfa , Magone Maria E. , Wang Ning , Lane Suzanne
Published: December 2020

The issue of linking testing with instructional practice is not new. In recent years, mathematics educators have been redefining the goals of mathematics education to include increased attention to problem solving and reasoning. For example, the National Council of Teachers of Mathematics's Curriculum and Evaluation Standards for School Mathematics (1989) and Professional Standards for Teaching Mathematics (1991) and the National Research Council's Everybody Counts (1989) suggest an emphasis on reasoning, problem solving, conceptual understanding, and communicating mathematically.
Students as Textbook Authors
Authors: Sosenke Fanny
Published: December 2020

Writing in mathematics has already been recognized as a very meaningful learning activity. Johnson (1983) suggests that if students can write clearly about mathematical concepts, then they probably understand them. In my classes, I frequently give students opportunities to write. Students write about their problem-solving strategies and about their understanding of new concepts; they also try their hand at writing word problems. Last year, my eighth-grade first-year-algebra students worked in groups writing a chapter on factoring polynomials for an algebra textbook. This was the first time I had used writing as an integral part of a long-term assignment. The two-week project described in this article was designed as a response to the students' need for new learning experiences and my need for new assessment tools. As an added benefit, the activity proved to be an excellent way for students to review material in a way that made them think in fresh terms.
Promoting Number Sense in the Middle Grades
Authors: Reys Barbara J.
Published: December 2020

Phrases such as “number sense,” “Operation sense,” and “intuitive understanding of number” are used throughout the Curriculum and Evaluation Standards for School Mathematics (NCTM 1989) to describe an intangible quality possessed by successful mathematics learners. Number sense refers to an intuitive feeling for numbers and their various uses and interpretations, an appreciation for various levels of accuracy when computing, the ability to detect arithmetical errors, and a common-sense approach to using numbers (Howden 1989; McIntosh, Reys, and Reys 1991). Number sense is not a finite entity that a student either has or does not have but rather a process that develops and matures with experience and knowledge. It does not develop by chance, nor does being skilled at manipulating numbers necessarily reflect this acquaintance and familiarity with numbers. Above all, number sense is characterized by a desire to make sense of numerical situations, including relating numbers to context and analyzing the effect of manipulations on numbers. It is a way of thinking that should permeate all aspects of mathematics teaching and learning.
Power On!: Learning Statistics with Technology
Authors: Kader Gary , Perry Mike
Published: December 2020

In its Curriculum and Evaluation Standards for School Mathematics (1989), the National Council of Teachers of Mathematics recommends that the K-12 mathematics curriculum be broadened and designates statistics as an area deserving increased attention. The standards document promotes the concept that statistics be learned through the study of real problems with real data collected by the students. Rather than focus on developing formulas from which answers are simply computed, teachers should present statistics in a coherent fashion and develop the topic as a whole problem-solving process.
The Thinking of Students: A Puzzling Letter
Authors: Newton-Hamill Alicia , Pierce Lura Goodhue
Published: December 2020

This department shares the thinking of middle school students as they explore and communicate mathematics. It will highlight students' work, including projects, investigations, or creative solutions to the problems in the monthly menu. Original student work will be included along with sufficient information about the activity so that readers can try the same ideas with their students. Please send articles and information for “The Thinking of Students” to the editor of the department: Karen Higgins, 28669 Royal Avenue, Eugene, OR 97402; home telephone (503) 688-1759. If readers need additional information, please include name, home address, home telephone number, and school name with the article. Please submit slides or photographs when possible. Submissions do not have to be in polished form, as the column can be written from the information the editor receives.
National Council of Teachers of Mathematics: Linking Yesterday to Tomorrow
Authors: Lindquist Mary M.
Published: December 2020

“Linkages,” Our Theme For This year's annual meeting, represents more than linking yesterday to tomorrow. It is about linking today. We need to link in many ways-with members, with each of the Affiliated Groups, with our committees and task forces, with the Headquarters staff, and with other professional groups. Most important, we need to link with our students. who are facing a much different world from the one that many of us experienced as students. We need to help them link ideas within mathematics and between mathematical topics and link mathematics to real-world problems. We need to strengthen many of our links, forge new ones, and sever some links to the past.
Graphing Calculators Aren't Just for High School Students
Authors: Taylor Linda J. C. , Nichols Jeri A.
Published: December 2020

Graphing calculators are revolutionizing the learning and teaching of mathematics. Students can view and manipulate graphs of functions in a matter of seconds. Such features as “plot,” “graph,” “trace,” and “zoom” offer opportunities for users to develop an understanding of the terms variable and function. According to the Curriculum and Evaluation Standards for School Mathematics (NCTM 1989), these concepts are vital aspects of the middle school curriculum. According to the standards document, “[A]n ideal 5-8 mathematics curriculum would expand students' knowledge of numbers,… patterns and functions, and the fundamental concepts of algebra” (pp. 65-66). In addition, “[T]echnology, including calculators, computers, and videos, should be used when appropriate” (p. 67). It stand to reason that tools to aid in understanding such concepts as variable and function, specifically graphing calculators, should not be reserved for high school juniors and seniors. This article discusses the use of graphing calculators by students of middle school age in an enrichment program for academically able, but economically disadvantaged, students. The exercises described helped students develop an understanding about variable and function. Students were actively engaged in problem solving that involved hands-on, real-life activities.
Introducing Prealgebra Skills in an Egg-citing Way
Authors: Talbert Martha Kay , Stallings-Roberts Virginia
Published: December 2020

Like most teachers, the authors would frequently meet between classes and during office hours to plan and bounce teaching ideas off of each other. One day we were bemoaning the fact that some students could not seem to understand what a variable was, much less manipulate algebraic expressions. The discussion was a familiar one. Troubled students would magically transform the expression 2x + x to 2x2. Or these same beleaguered souls would decide that the easiest way to deal with substitution is to ignore it. While we were pondeting ways in which we could reach students, one of us excitedly pointed out that algebra is hidden arithmetic! It was then that the idea of eggalgebra began to unfold. The activity was primarily designed to help students understand the concept of a variable and the process of gathering like terms or simplifying algebraic expressions. We have found that students across many grade levels have appreciated and gained from working with egg-algebra.
Cartoon Corner
Authors: Cain Barbara
Published: December 2020

“Cartoon Corner” is designed to include cartoons that can be used to highlight mathematics in an interesting way. The questions accompanyin the cartoons can be used as a large- or small-group in class activity, as homework, or as an extra-credit assignment. Students might want to create their own mathematics related cartoons that demonstrate in a humorous way how mathematics is used and misused. Readers are encouraged to submit three copies of cartoons and classroom tested questions, double-spaced, for review by the editor of this section. The cartoons must include the date and the newspaper syndicate that holds the copyright.
Power On! Bringing Geometry into the Classroom with Videodisc Technology
Authors: Zech Linda , Vye Nancy J. , Bransford John D. , Swink Jeff , Mayfield-Stewart Cynthia , Goldman Susan R. , _ _
Published: December 2020

Geometry is derived from two greek words that literally mean “earth measure.” Its roots reveal the origination of geometry as a study of the measure and relationship of elements of the world. Geometry as a study of the world is also recommended for middle school students (Geddes 1992. 2, 7).
The Ratio Table
Authors: Middleton James A. , van den Heuvel-Panhuizen Marja
Published: December 2020

The middle grades offer unique challenges to the mathematics teacher, especially in this time of transition from traditional to reformed curricula and methods. The range and conceptual quality of mathematical knowledge that students have as they enter grades 5 and 6 vary greatly. Many students have been accelerated through textbooks, resulting in a high degree of proficiency at arithmetic computation but sometimes with little conceptual understanding of the underlying mathematics. Many other students will enter the middle grades with only rudimentary understanding of addition and subtraction. This disparity of skills and understanding creates a difficult dilemma for middle school teachers. Should they review the arithmetic that students have already experienced, or should they forge ahead to a higher level of more difficult mathematics? This decision need not be perceived as a dichotomy. Methods exist for exploring higher-order mathematical topics conceptually that allow understanding by students of varying knowledge levels whatever their base knowledge may be.
Now & Then: Roger Whitmore, Police Officer
Authors: Barnes Sue , Dee Michalowicz Karen
Published: December 2020

Now… roger whitmore is an arkansas state highway patrolman for Sevier County. Only one other trooper is assigned to the county, so Roger and his coworker, Phillip Glasgow, must share a rotating-duty schedule. Roger began his career in law enforcement after he graduated from high school by becoming a patrolman for Ashdown, a small town in southwest Arkansas where he grew up. Roger decided on a career in law enforcement because he wanted to help people and he found that the everyday job of a police officer is serving people.
The Thinking of Students: Making House Plans
Authors: Hanson David , Boranbay Serra
Published: December 2020

Seventh-grade students at robert college (grades 7-12) in Istanbul, Turkey, have been involved in making scale drawings. They were instructed to make a rough drawing of their apartments and to measure them in any way they wanted. Some students measured in meters, some in centimeters, and some in feet and inches. Other students paced off their apartments.
On My Mind: Bill Gates and the “Filter Girl”
Authors: Reutter Juli M.
Published: December 2020

He's my age!” I thought as i listened to the speaker. Mathematics educators, gathered at the annual NCTM conference in Seattle, were concentrating as Bill Gates, the local boy, described mathematics from his perspective: marginal school success; a teacher who noticed and nurtured a talent and interest; bake sales to fund his school's everincreasing computer time-share. The visionary founder of Microsoft patiently answered our questions about the role of mathematics, technology, and standards in this information age. I marveled during Gates's software demonstration of The Geometer's Sketchpad. “Wow,” I said as I watched, amazed, the geometry of bees on CD-ROM.
Flower Beds and Landscape Consultants: Making Connections in Middle School Mathematics
Authors: Hersberger Jim , Frederick Bill
Published: December 2020

For several years, the following problem has been presented in algebra and calculus classes, elementary education classes, and inservice sessions on problem solving:
Playing Green Globs on a TI-81
Authors: Owens John E.
Published: December 2020

Green globs (dugdale and kibbey 1985) has been a staple of first-year-algebra courses for several years (see fig. 1). In the game, thirteen green globs are randomly placed by the computer at integer coordinates on a grid (- 10 ≤ x ≤ 10; -8 ≤ y ≤ 8). The player's task is to devise a function that touches as many globs as possible, thereby bursting them. The player continues to enter functions until all globs are exploded. The game presents an enjoyable context for students to explore and practice graphical representations of a range of functions.
Now & Then: Ingrid Proctor-Fridia: Quality Assurance Representative
Authors: Barnes Sue , Michalowicz Karen Dee
Published: December 2020

Now… ingrid proctor-fridia holds two college degrees, but when she dresses for work each morning, she does not necessarily don a business suit and high-heeled shoes. Sometimes she chooses jeans: even when she dresses up for work, she carries along a pair of coveralls to be on the safe side.