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Individuals with visual impairment (VI) require aids such as white canes and guide dogs to navigate their environments. Modern localisation technologies have the capacity to transform the way individuals with VI navigate surroundings, but they have yet to do so. A critical barrier is the inability of human–machine interfaces to communicate precise navigation instructions non-visually. We present a shape changing haptic interface (Shape) that provides spatial guidance in two dimensions via bending of its body. Individuals with VI and sighted individuals were recruited to locate virtual targets in 3D space using Shape and vibration feedback (Vibration), and sighted individuals were also asked to visually locate targets. Throughout, device orientation and position were tracked in real-time using a virtual reality system. Individuals with VI located targets significantly faster and more efficiently using Shape, than with Vibration, and there were no significant differences in time or efficiency between Shape and natural vision. Moreover, participants scored Shape significantly more positively than Vibration in a Likert user experience survey, while no significant differences were observed between Shape and natural vision. Here, we provide compelling evidence for the application of a new shape-changing haptic interface as part of an effective future digital navigation system for individuals with VI. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to investigate the effects of locking plugs and the biomechanical properties of a 3.5 mm 8-hole polyaxial locking plate in a fracture gap model. Our hypothesis was that locking plugs would increase the strength and stiffness of the construct. Twelve 3.5 mm 8-hole plates were used to evaluate two different construct designs (with locking plugs vs. without locking plugs) with validated bone substitutes in a 25 mm bridging osteosynthesis gap model. Each construct was subjected to a single cycle four-point bending load to failure using a servo-hydraulic testing machine. Bending stiffness, bending strength, and bending structural stiffness were calculated and compared using an unpaired Student´s t-test. Results: The plating construct with locking plugs did not show any significant increase in terms of bending stiffness, bending strength, and bending structural stiffness compared to plating construct without locking plugs in a 25 mm gap fracture model during a single cycle four-point bending. Conclusions: Under the conditions tested, filling empty plate holes with locking plugs in bridging osteosynthesis does not increase stiffness or strength of the plate-bone construct. [ABSTRACT FROM AUTHOR]

The thermoelectric performance of ACuP (A = Mg and Ca) with abundant elements and low gravimetric density is reported. Both systems are p-type doped by intrinsic Cu vacancy defects, have large power factors and promising figures of merit, reaching zT = 0.5 at 800 K. This demonstrates that copper phosphides are a potential new class of thermoelectric materials for waste heat harvesting. [ABSTRACT FROM AUTHOR]

Semimetals have recently emerged at the forefront of contemporary thermoelectrics research. In this paper, we show that the candidate Dirac semimetal CaAgP forms with a stable CaAg0.9P composition. Intentionally, Ag-deficient CaAg0.9P shows a promising thermoelectric figure of merit, achieving zT = 0.43 at 660 K. This derives from moderate power factors, S2/ρ = 1.25 mW m−1 K−2, and a low lattice thermal conductivity, κlat = 1.2 W m−1 K−1. The thermoelectric properties of CaAg0.9P are consistent with that of a small bandgap semiconductor. High levels of doping are key to suppressing bipolar transport, enabling promising zT values, despite the low ∼0.2 eV bandgap. Unusually, the onset of bipolar transport coincides with a transition to a more electrically resistive state, indicating a fundamental change in electronic properties at high temperature. [ABSTRACT FROM AUTHOR]

Background: Guidelines recommend nephrology referral for people with advanced non-dialysis-dependent chronic kidney disease, based mostly on survival benefits seen in retrospective studies of dialysis patients, which may not be generalizable to the broader population with chronic kidney disease. We aimed to examine the association between outpatient nephrology consultation and survival in adults with stage 4 chronic kidney disease.Methods: We linked population-based laboratory and administrative data from 2002 to 2014 in Alberta, Canada, on adults with stage 4 chronic kidney disease (sustained estimated glomerular filtration rate ≥ 15 to < 30 mL/min/1.73 m2 for > 90 d), who had never had kidney failure and had had no outpatient nephrology encounter in the 2 years preceding study entry. Participants who had never had an outpatient nephrology visit before renal replacement treatment were considered "unexposed." Participants who saw a nephrologist during follow-up were considered "unexposed" before the first outpatient nephrology visit and "exposed" thereafter. The primary outcome was all-cause mortality.Results: Of the 14 382 study participants (median follow-up 2.7 yr), 64% were aged ≥ 80 years, 35% saw a nephrologist and 66% died during follow-up. Nephrology consultation was associated with lower mortality (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.82-0.93). The association was strongest in people < 70 years (HR 0.78, 95% CI, 0.65-0.92), progressively weaker with increasing age, and absent in people ≥ 90 years (HR 1.05, 95% CI 0.88-1.25).Interpretation: The survival benefit of nephrology consultation in adults with stage 4 chronic kidney disease may be smaller than expected and appears to attenuate with increasing age. These findings should inform recommendations for nephrology referral considering the advanced age of the patient population meeting current referral criteria. [ABSTRACT FROM AUTHOR]

A proportion of end-stage kidney disease (ESKD) patients require kidney replacement therapy to maintain clinical stability. Home dialysis therapies offer convenience, autonomy and potential quality of life improvements, all of which were heightened during the COVID-19 pandemic. While the superiority of specific modalities remains uncertain, patient choice and informed decision-making remain crucial. Missed opportunities for home therapies arise from systemic, programmatic and patient-level barriers. This paper introduces the integrated care model which prioritizes the safe and effective uptake of home therapies while also emphasizing patient-centered care, informed decision-making, and comprehensive support. The integrated care framework addresses challenges in patient identification, assessment, eligibility determination, education and modality transitions. Special considerations for urgent dialysis starts are discussed, acknowledging the unique barriers faced by this population. Continuous quality improvement is emphasized, with the understanding that local challenges may require tailored solutions. Overall, the integrated care model aims to create a seamless and beneficial transition to home dialysis therapies, promoting flexibility and improved quality of life for ESKD patients globally. [ABSTRACT FROM AUTHOR]

The article focuses niche partitioning of a pathogenic microbiome driven by chemical gradients and effects can be particularly important for dysbiotic shifts in microbiome structure that are often associated with disease. It mentions pH and oxygen strongly partition the microbial community from a diseased human lung into two mutually exclusive communities of pathogens and anaerobe. It also mentions antimicrobial treatment disrupted this chemical partitioning.

Epizootic shell disease (ESD) is causing major losses to the lobster fishery in southern New England. Potential pathogens have been identified in lesion communities, but there are currently no efficient means of detecting and quantifying their presence. A qPCR assay was developed for a key potential pathogen, Aquimarina macrocephali subsp. homaria found to be ubiquitous in ESD lesions but not the unaffected integument. Application of the assay to various samples demonstrated that A. macrocephali subsp. homaria is ubiquitous and abundant in lobster lesions, commonly associated with healthy surfaces of crabs and is scarce in water and sediment samples from southern New England suggesting the affinity of this microorganism to the Arthropod integument. The qPCR assay developed here can be applied in future in vivo and in vitro studies to better understand the ecology and role of A. macrocephali subsp. homaria . in shell disease. [ABSTRACT FROM AUTHOR]

Purpose – Kim Cameron and Robert Quinn are two widely admired world class scholars at the University of Michigan’s Ross School of Business. The purpose of this paper is to explore their personal views about positive leadership and added values over the traditional approach to organizations and leadership. Design/methodology/approach – This interview was designed to obtain personal insights to positive leadership from world renowned leadership scholars. Findings – Most people do have something to give that is worthwhile, when they address the question of positive leadership over traditional leadership. The moment we orient people to their highest purpose, there is an incentive for them to close their integrity gap. Originality/value – Obtaining personal insights from lifelong scholars of leadership by means of personal interviews is paramount in the professional field of leadership. [ABSTRACT FROM AUTHOR]

Molecular networking is a tandem mass spectrometry (MS/MS) data organizational approach that has been recently introduced in the drug discovery, metabolomics, and medical fields. The chemistry of molecules dictates how they will be fragmented by MS/MS in the gas phase and, therefore, two related molecules are likely to display similar fragment ion spectra. Molecular networking organizes the MS/MS data as a relational spectral network thereby mapping the chemistry that was detected in an MS/MS-based metabolomics experiment. Although the wider utility of molecular networking is just beginning to be recognized, in this review we highlight the principles behind molecular networking and its use for the discovery of therapeutic leads, monitoring drug metabolism, clinical diagnostics, and emerging applications in precision medicine. [ABSTRACT FROM AUTHOR]

The article discusses the use of criteria for the management of hip fractures among older people by the American Academy of Orthopaedic Surgeons. It mentions that the said criteria based on a review of medical literature on the treatment of hip fractures in the elderly. It cites the indications and sub-classifications or treatment of patients with hip fracture.

Holobionts are assemblages of microbial symbionts and their macrobial host. As extant representatives of some of the oldest macro-organisms, corals and algae are important for understanding how holobionts develop and interact with one another. Using untargeted metabolomics, we show that non-self interactions altered the coral metabolome more than self-interactions (i.e. different or same genus, respectively). Platelet activating factor (PAF) and Lyso-PAF, central inflammatory modulators in mammals, were major lipid components of the coral holobionts. When corals were damaged during competitive interactions with algae, PAF increased along with expression of the gene encoding Lyso-PAF acetyltransferase; the protein responsible for converting Lyso-PAF to PAF. This shows that self and non-self recognition among some of the oldest extant holobionts involve bioactive lipids identical to those in highly derived taxa like humans. This further strengthens the hypothesis that major players of the immune response evolved during the pre-Cambrian. [ABSTRACT FROM AUTHOR]

There is a poor understanding of how the physiology of polymicrobial communities in cystic fibrosis (CF) lungs contributes to pulmonary exacerbations and lung function decline. In this study, a microbial culture system based on the principles of the Winogradsky column (WinCF system) was developed to study the physiology of CF microbes. The system used glass capillary tubes filled with artificial sputum medium to mimic a clogged airway bronchiole. Chemical indicators were added to observe microbial physiology within the tubes. Characterization of sputum samples from seven patients showed variation in pH, respiration, biofilm formation and gas production, indicating that the physiology of CF microbial communities varied among patients. Incubation of homogenized tissues from an explant CF lung mirrored responses of a Pseudomonas aeruginosa pure culture, supporting evidence that end-stage lungs are dominated by this pathogen. Longitudinal sputum samples taken through two exacerbation events in a single patient showed that a two-unit drop in pH and a 30% increase in gas production occurred in the tubes prior to exacerbation, which was reversed with antibiotic treatment. Microbial community profiles obtained through amplification and sequencing of the 16S rRNA gene showed that fermentative anaerobes became more abundant during exacerbation and were then reduced during treatment where P. aeruginosa became the dominant bacterium. Results from the WinCF experiments support the model where two functionally different CF microbial communities exist, the persistent Climax Community and the acute Attack Community. Fermentative anaerobes are hypothesized to be the core members of the Attack Community and production of acidic and gaseous products from fermentation may drive developing exacerbations. Treatment targeting the Attack Community may better resolve exacerbations and resulting lung damage. [ABSTRACT FROM AUTHOR]

The article discusses the Appropriate Use Criteria (AUC) for the Surgical Management of Osteoarthritis of the Knee which was developed by the American Academy of Orthopaedic Surgeons. The AUC was created based on the review of available literature on the surgical management of osteoarthritis of the knee, operative procedures and a list of clinical patient scenarios. Charts that show patient indications and sub-classifications, and the breakdown of appropriateness ratings are offered.

Background Fluid removal during dialysis, also known as ultrafiltration (UF), leads to intradialytic hypotension (IDH) in a significant number of patients treated with hemodialysis (HD) and is associated with an increase in morbidity and mortality. At present, there are no accepted standards of practice for the prevention or treatment of IDH. Relative blood volume monitoring (BVM) is based on the concept that the hematocrit increases with UF, relative to the patient's baseline hematocrit. The use of BVM biofeedback, whereby the HD machine automatically adjusts the rate of UF based on the relative blood volume, has been proposed for the prevention of IDH. Methods/Design This is a 22-week randomized crossover trial. Participants undergo a 4-week run-in phase to standardize medications and dialysis prescriptions. Subsequently, participants are randomized to standard HD or to BVM biofeedback for a period of 8 weeks followed by a 2-week washout phase before crossing over. The dialysis prescription remains identical for both arms. The primary outcome is the frequency of symptomatic IDH as defined by an abrupt drop in the systolic blood pressure of =20 mm Hg accompanied by headache, dizziness, loss of consciousness, thirst, dyspnea, angina, muscle cramps or vomiting. Secondary outcomes include the number of symptomatic IDH episodes and any reduction in IDH episodes, nursing interventions, dialysis adequacy, total body water, extra- and intracellular fluid volumes, brain natriuretic peptide and cardiac troponin levels, blood pressure, antihypertensive medication use, patient symptoms and quality of life. Discussion Our study will determine the impact of using BVM biofeedback to prevent IDH and other serious adverse events in susceptible patients. [ABSTRACT FROM AUTHOR]

Many human rights defenders operate from within higher education institutions, research institutes, academies, societies and ‘think-tanks'. Many of these academics, researchers and lecturers would recognise themselves as human rights defenders because their academic work is consciously paired with rights-promoting education and advocacy. Others may not set out to be human rights defenders, but are cast in the role after being targeted for attack. Human rights claims arising out of such attacks on intellectual-HRDs, if brought, typically do not include claims for violations of academic freedom. As a result the standards are underdeveloped relative to other human rights claims and the scope of academic freedom violations globally. This may be in part due to a negatively reinforcing lack of familiarity with issues of academic freedom and the available standards for protection among human rights advocates, and in part to the fact that attacks on academic freedom often manifest as violations of other rights under which claims are brought (e.g. wrongful detention or torture). This article argues that existing human rights law would sustain claims for violations of academic freedom as independently and interdependently derived from the rights to freedom of opinion and expression and the right to education. This article argues that including academic freedom claims in such cases has the benefit of providing an additional basis for relief while strengthening the claim for relief on a manifested violation by providing evidence of motive and intent. Including academic freedom claims also has the independent value of addressing the wider harms to the claimant-victim and society that result from attacks on intellectual expression and are not reached by relief on the manifested violation alone, including harms to a claimant-victim's creative, intellectual or expressive work, and widespread chilling effects on creativity, teaching, publication and the free exchange of ideas in society. [ABSTRACT FROM AUTHOR]

Background People with kidney allograft failure represent an increasing fraction of all those starting dialysis therapy. We sought to summarize prognosis following kidney allograft failure and identify potentially beneficial interventions or modifiable risk factors. Methods We searched MEDLINE and EMBASE (inception to 1 October 2013) and article reference lists without language restriction and selected cohort studies of all-cause mortality and fatal infection-related and cardiovascular events in people starting dialysis following kidney allograft failure. Two reviewers independently extracted data on study design, participant characteristics, dialysis modality, transplant nephrectomy, immunosuppression strategy, transplant-naive comparators and risk of bias. Discrepancies were resolved with a third reviewer. Results Forty studies comprising 249 716 participants met the inclusion criteria. The first year of dialysis therapy was associated with the highest mortality. By random effects meta-analysis, annual risk of death, from years 1 to 4, was 0.12 [95% confidence interval (95% CI): 0.09–0.15], 0.06 (95% CI: 0.05–0.07), 0.05 (95% CI: 0.04–0.06) and 0.05 (95% CI: 0.04–0.06), respectively. We found high heterogeneity in each meta-analysis, which remained unexplained by prespecified subgroup analyses. We could not find sufficient information to summarize the risk for fatal infection-related and cardiovascular events, or to test the role of transplant nephrectomy or different immunosuppressive strategies. Risk of bias was high, especially participation bias. Conclusion Mortality is higher during the first year of dialysis treatment following kidney allograft failure than in subsequent years. Insufficient data are available to assess factors or interventions potentially impacting prognosis following kidney allograft failure. In a culture promoting transplantation, clinical research of different models of care in this growing high-risk population should be a research priority. [ABSTRACT FROM AUTHOR]

The article offers tips and tools for general practitioners on the contemporary management of metastatic bone disease. It states that the aging population and improved survival rate of patients with cancer led to the increase in metastatic bone disease. It mentions that fracture stabilization with internal fixation or arthroplasty can improve quality of life and patient mobility. It adds that endoprosthetic reconstruction is the ideal treatment for femoral head and neck injuries.

Shell disease is a major threat to the American lobster ( Homarus americanus, Milne Edwards) fishery. Here we describe the composition of microbial communities associated with lesions of 2 forms of shell disease in Atlantic Canada, ( i) a trauma shell disease (TSD) characterized by massive lesions and ( ii) an enzootic shell disease (EnSD) characterized by irregularly shaped lesions with a distinct orange to yellow color. The microbiology of the lesions was described by polymerase chain reaction and denaturing gradient gel electrophoresis of 16S rDNA amplified from scrapings of the shell lesions and was compared with communities of unaffected carapaces and previously described forms of shell diseases. Both TSD and EnSD lesions were dominated by members of Alphaproteobacteria, Gammaproteobacteria, and Flavobacteria, all commonly detected in other forms of shell disease; however, unique members of Epsilonproteobacteria were also present. Two Vibrio spp. and 2 Pseudoalteromonas spp. were dominant in lesions of TSD and a Tenacibaculum sp. and Tenacibaculum ovolyticum were dominant in lesions of EnSD. The TSD and EnSD in this study contained similar taxa as other shell disease forms; however, their microbiology is mostly different and neither resembles that of epizootic shell disease. [ABSTRACT FROM AUTHOR]

Capture of carbon dioxide from combustion processes presentsaunique and challenging technical problem arising from low CO2partial pressures, high flow rates, and the presence of water vaporand reactive contaminants such as SO2. A series of solidsorbents were evaluated to determine suitability for postcombustioncapture. A lithium orthosilicate (Li4SiO4)-basedabsorbent supplied by Toshiba Corporation was found to have the mostpromising properties. The absorbent reacts chemically with CO2at elevated temperatures (550 °C) to form lithium carbonate(Li2CO3) and lithium metasilicate (Li2SiO3). The presence of water vapor was shown to greatlyenhance CO2absorption rates without affecting capacity.Breakthrough capacities of ∼5–6 mmol/g (22–26wt %) were obtained using a “clean” synthetic flue gascontaining 15% CO2and 10% H2O in N2at 550 °C. Experimental studies showed that the absorbent usedin a fixed bed process will likely require a thermal swing processwith absorption at 550 °C and regeneration at 650 °C. Evenfor the high capacity of the Li4SiO4-based absorbent,an alternative to conventional fixed bed technology will be requiredfor practical postcombustion capture from coal-fired power plants.Processes that can shorten cycle times by rapidly heating and coolingvessels and/or sorbents will be needed, and possible alternativesare described. [ABSTRACT FROM AUTHOR]

Abstract: Background: Acute kidney injury frequently arises within an acute care hospitalization. Outcomes among acute kidney injury survivors following hospital discharge are poorly documented. Methods: We conducted a population-based cohort study between 1996 and 2006 of all adult patients in Ontario with acute kidney injury who did not require in-hospital dialysis, and who survived free of dialysis ≥30 days after discharge. Those with acute kidney injury (n=41,327) were matched 1:1 to patients without acute kidney injury during their index hospitalization. Matching was by age (±1 year), sex, history of chronic kidney disease, receipt of mechanical ventilation during the index hospitalization, and a propensity score for developing acute kidney injury. The primary outcome was subsequent need for chronic dialysis. The secondary outcomes were all-cause mortality and rehospitalization. Results: Mean age was 70 years, and median follow-up was 2 years (maximum 10 years). The incidence of chronic dialysis was 1.78 per 100 person-years among those with acute kidney injury and 0.74 per 100 person-years among unaffected controls (adjusted hazard ratio [HR]; 2.70, 95% confidence interval [CI], 2.42-3.00). Rates also were higher for all-cause mortality (15.34 vs 14.51 per-100 person-years; adjusted HR 1.10; 95% CI, 1.07-1.13) and rehospitalization (44.93 vs 37.18 per 100 person-years; adjusted HR 1.21; 95% CI, 1.18-1.24). Conclusion: Even when acute dialysis is not required, survivors of acute kidney injury remain at higher risk of receipt of chronic dialysis thereafter. The absolute risk of death was more than 8 times the rate of chronic dialysis. [Copyright &y& Elsevier]

Denaturing gradient gel electrophoresis (DGGE) of 16S rDNA was used to nonlethally detect Aeromonas salmonicida and other bacteria in salmonid skin mucus. Mucus samples from wild spawning coho salmon ( Oncorhynchus kisutch) with endemic A. salmonicida and from cultured lake trout ( Salvelinus namaycush) were tested by PCR-DGGE and were compared with mucus culture on Coomassie brilliant blue agar and internal organ culture. PCR-DGGE gave a highly reproducible 4-band pattern for 9 strains of typical A. salmonicida, which was different from other Aeromonas spp. Aeromonas salmonicida presence in mucus was evident as a band that comigrated with the bottom band of the A. salmonicida 4-band pattern and was verified by sequencing. PCR-DGGE found 36 of 52 coho salmon positive for A. salmonicida, compared with 31 positive by mucus culture and 16 by organ culture. Numerous other bacteria were detected in salmonid mucus, including Pseudomonas spp., Shewanella putrefaciens, Aeromonas hydrophila and other aeromonads. However, Yersinia ruckeri was not detected in mucus from 27 lake trout, but 1 fish had a sorbitol-positive Y. ruckeri isolated from organ culture. Yersinia ruckeri seeded into a mucus sample suggested that PCR-DGGE detection of this bacterium from mucus was possible. PCR-DGGE allows nonlethal detection of A. salmonicida in mucus and differentiation of some Aeromonas spp. and has the potential to allow simultaneous detection of other pathogens present in fish mucus. [ABSTRACT FROM AUTHOR]

The article discusses the Appropriate Use Criteria for the management of patients with orthopaedic implants undergoing dental prophylaxis voted by the members of the American Academy of Orthopaedic Surgeons. Topics include the list of patient scenarios based on indications and sub-classifications along with treatment developed by the Writing Panel, the review of the scenarios and treatments and the determination of appropriateness levels using the median value of the second-round ratings.

We present a simple card game whose payout depends on a player's strategy, as well as on chance. Solutions require the use of conditional analysis and the computation of expected values. [ABSTRACT FROM AUTHOR]

Glucosidase II (GluII) is a glycan-trimming enzyme active on nascent glycoproteins in the endoplasmic reticulum (ER). It trims the middle and innermost glucose residues (Glc2 and Glc1) from N-linked glycans. The monoglucosylated glycan produced by the first GluII trimming reaction is recognized by calnexin/calreticulin and serves as the signal for entry into this folding pathway. GluII is a heterodimer of α and β subunits corresponding to yeast Gls2p and Gtb1p, respectively. While Gls2p contains the glucosyl hydrolase active site, the Gtb1p subunit has previously been shown to be essential for the Glc1 trimming event. Here we demonstrate that Gtb1p also determines the rate of Glc2 trimming. In order to further dissect these activities we mutagenized a number of conserved residues across the protein. Our data demonstrate that both the MRH and G2B domains of Gtb1p contribute to the Glc2 trimming event but that the MRH domain is essential for Glc1 trimming. [ABSTRACT FROM PUBLISHER]

The article focuses on a population-based cohort study which assessed the risk of chronic dialysis and all-cause mortality in individuals who experience an episode of acute kidney injury requiring dialysis. The researchers used adult patients in Ontario with acute kidney injury who required in-hospital dialysis and survived free dialysis for at least 30 days after discharge between July 1, 1996 and December 31, 2006. The study found a 10.10 and 10.85 all-cause mortality rates per 100 person-years, respectively. It concluded that there is an association between acute kidney injury necessitating in-hospital dialysis with increased risk of chronic dialysis, but not all-cause mortality.

In this article, the authors identify and anecdotally describe three tutor archetypes: the pragmatist, the architect, and the surveyor. These descriptions, based on observations of remedial mathematics tutors at a land-grant university, shed light on a variety of philosophical beliefs regarding and pedagogical approaches to tutoring. An analysis of these archetypes is beneficial not only to tutors and tutor supervisors but also to mathematics instructors at all levels. By considering these archetypes, tutors and instructors should recognize their personal strengths and the areas in which they could improve. Supervisors should encourage balanced approaches that incorporate the strengths of each of these archetypes. The authors hope this discussion will serve as a stepping-stone for future research in this critical area. [ABSTRACT FROM AUTHOR]

The article discusses the move of the author to implement investigative calculus projects to his students in their Calculus subject which allows students to explore their own question or problem. According to the author, he intends to strengthen the problem-solving skills of students as well as increase their interest and understanding of the course. In addition, he states that there are three important components of the program including the application of nontraditional assessment, conceptual understanding and problem solving. Furthermore, he presents several parameters of the program as well as gives details on the top three projects that were submitted.

Dividing by zero can be confusing for students at all levels. If teachers are to provide clear and understandable explanations of this topic, they must possess a strong conceptual understanding of it themselves. In this article, the authors present qualitative data on fourth through eighth-grade teachers' perceptions of division by zero. They discuss three categories: teachers who did not know that division by zero is undefined; teachers who knew that division by zero is undefined but could not provide an explanation; and, teachers who displayed correct conceptual understanding of division by zero. The authors conclude with several explanations of dividing by zero that should help teachers understand this topic by making appropriate connections to multiplication and division of positive integers. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study on the relationship between algebra students' proficiency with fractions and their success in algebra. It defines proficiency as the ability of the student to not only understand fraction concepts, but also to manipulate fractions for accurate computation without using a calculator. It explains the reason behind the poor performance of elementary algebra students on the fraction test. It presents recommendations for teaching fraction concepts to students.

The article presents a mathematical problem. A mathematical problem that combines algebraic concepts and geometric concepts is presented and discussed. The authors presented the rowboat problem and discussed the different solution strategies that can be used to solved it. They argue that the problem is an eye opener for high school students to explore, conjecture, connect and prove in its algebraic and geometric content. They explored possible ways to solve the problem by utilizing deductive proof and coordinate geometry proof.

The article discusses research being done on fractions and algebra. Studies on issues related to when fractions should be taught, how fractions should be taught, and how competence with fractions affects the transition from arithmetic to algebra are considered. Based on the studies discussed, it seems apparent that teachers need to reform the pedagogies by which they teach fractions.

An instrumented EURO I Ford Mondeo was used to perform a real-world comparison of vehicle exhaust (carbon dioxide, carbon monoxide, hydrocarbons and oxides of nitrogen) emissions and fuel consumption for diesel and 5% biodiesel in diesel blend (B5) fuels. Data were collected on multiple replicates of three standardised on-road journeys: (1) a simple urban route; (2) a combined urban/inter-urban route; and, (3) an urban route subject to significant traffic management. At the total journey measurement level, data collected here indicate that replacing diesel with a B5 substitute could result in significant increases in both NO x emissions (8–13%) and fuel consumption (7–8%). However, statistical analysis of probe vehicle data demonstrated the limitations of comparisons based on such total journey measurements, i.e., methods analogous to those used in conventional dynamometer/drive cycle fuel comparison studies. Here, methods based on the comparison of speed/acceleration emissions and fuel consumption maps are presented. Significant variations across the speed/acceleration surface indicated that direct emission and fuel consumption impacts were highly dependent on the journey/drive cycle employed. The emission and fuel consumption maps were used both as descriptive tools to characterise impacts and predictive tools to estimate journey-specific emission and fuel consumption effects. [Copyright &y& Elsevier]

The article presents an analysis of students' difficulty with fractions using a twenty-five-question test of concept knowledge and computational fluency. The error analysis revealed that most of the students have a fragmented understanding of fraction concepts and operations and opted to use algorithm in test items that could be solved by applying a concept. The time for fractions spent before grade 6 should be devoted to develop a conceptual base of fraction relationships.

This article explores the relationships between several pairs of statistics kept on professional golfers on the PGA tour. Specifically, two measures related to the player's ability to drive the ball are compared as are two measures related to the player's ability to putt. An additional analysis is made between one statistic related to putting and another that measures how effectively the player tends to reach the green. An analysis of which statistic has the most impact on a player's score is also included. The article concludes with an interesting extension relating the statistics of professionals to the performance of an amateur golfer. [ABSTRACT FROM AUTHOR]

Discusses a constructivist lesson that introduces arithmetic sequences through the use of patterns. Components of the lesson; Stages of the lesson; General and recursive solutions developed from the exercise.

Presents a study that examined the effects of mentoring on first-year teachers' perceptions of support received. Methodology; Results; Implications; Conclusion.

Presents a 2004 study which determined the problems faced by first year teachers in middle and high school level schools in the U.S. Responsibilities given to first year teachers; Percentage of the respondents who handles three or more classes; Features of the Elementary and Secondary Education Act.

Focuses on injuries of experienced workers in industrial accidents in the U.S. Likelihood of accidents in the industrial sector; Discussion of the concept of risk homeostasis; Assessment of the level of risk associated with an activity as compared to a person's acceptable level; Tendency of individuals to regulate their behavior in order to maintain a homeostasis between risk-exposure and risk-avoidance.

Provides information on a study that determines if the amount of support first-year teachers perceived they received from their principals was significant compared to the total amount of support they believed they received. Methodology of the study; Discussion of the study; Conclusion.

Summary This article discusses three probabilistic scenarios based on the television game show ‘Who Wants to be a Millionaire?’. These situations provide motivational opportunities for high-school students to explore the concepts of expected value, permutations and independent events. [ABSTRACT FROM AUTHOR]

Presents an approach to teaching matrices that includes conceptual development with the use of problem solving questions. Matrices that students can use to calculate the number of hours of each type of work needed at each factory of a toy company; How to find the production cost per cycle at each factory; Benefits of the lesson to students.

Focuses on the use of attribute blocks to develop a conceptual understanding of probability for middle school students. Components of attribute blocks; Definition of probability; Discussion on the concept of independence using the attribute blocks.

Describes a lesson in algebra in which students are asked to apply their mathematical intuition to answer questions related to sports. Critical thinking skills developed through the exercise; Components of the activity.

Describes a method of teaching middle-grade students about fractions, decimals, and percentages, terms frequently used in mathematics. Phases of mathematical lessons; Goals aimed to be achieved by educators in teaching mathematics; Advantages of such teaching approach over traditional methods.

The article discusses the approach to the Appropriate Use Criteria (AUC) for the management of Anterior Cruciate Ligament (ACL) injuries. Topics discussed include the adaption of AUC development methods; the supervised ACL prevention program which include plyometrics, balance and proprioceptive training, and high-frequency utilization; and list of treatments rated for appropriateness such as self-directed exercise program and activity modification.

Population studies have shown that the infant's microbiome and metabolome undergo significant changes in early childhood. However, no previous study has investigated how diverse these changes are across subjects and whether the subject-specific dynamics of some microbes correlate with the over-time dynamics of specific metabolites. Using mixed-effects models, and data from the ABC study, we investigated the early childhood dynamics of fecal microbiome and metabolome and identified 83 amplicon sequence variants (ASVs) and 753 metabolites with seemingly coordinated trajectories. Enrichment analysis of these microbes and molecules revealed eight ASV families and 23 metabolite groups involving 1032 ASV-metabolite pairs with their presence-absence changing in a coordinated fashion. Members of the Lachnospiraceae (464/1032) and metabolites related to cholestane steroids (309/1032) dominated proportional shifts within the fecal microbiome and metabolome as infants aged. Longitudinal analyses of subject-specific dynamics in infants' microbiome and metabolome identified microbes and metabolites with seemingly coordinated dynamics. [ABSTRACT FROM AUTHOR]