173 research outputs found

    Strategic inventory management of externally sourced medical devices

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    Thesis (M. Eng. in Logistics)--Massachusetts Institute of Technology, Engineering Systems Division, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 59).The purpose of this research was to determine inventory strategies for externally sourced medical devices. In the medical device industry, the desire for high levels of customer service often results in less than optimal inventory levels. In this study, we analyzed the details of the current inventory model utilized by the medical device company. In assigning appropriate inventory levels, we determined that key inputs were not regarded. When evaluating inventory levels, it was determined that pipeline inventory should be removed from the target on hand inventory levels if inventory ownership occurs upon receipt. When calculating safety stock, we determined that supply variability should be incorporated into the safety stock formula and extra buffers currently in place should be removed. In addition, a more robust measure of demand variability such as the Root Mean Squared Error (RMSE) or the Mean Absolute Percent Error (MAPE) should be incorporated into the formula instead of the use of the maximum of standard deviation of demand and standard deviation of forecast. Also, a gap was identified between the customer service safety factor used in the safety stock formula and the measurement of customer service by the company. Following the analysis of the current inventory modeling approach, we segmented the medical device SKU's based on key factors that drive inventory: demand, lead time, criticality and customer service. We also redefined the model used to determine slow moving inventory levels by incorporating the lead time of the part in setting cycle and safety stock levels and simulating the results to validate the relationships between the various inventory drivers. The application of the methodologies, concepts and findings in this research covering externally sourced medical devices can be extended to other subsidiaries and other industries.by Nichole L. Hillstrom and Renato A. Malabanan.M.Eng.in Logistic

    The Effects of Integrating E-Media Piano in Teaching Music

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    Historically, schools, universities and adult education providers have used a “lecture-based” teaching model. This approach to learning was developed during the industrial age, some two centuries ago. The concept is for students to sit passively in rows of chairs or tables all facing the presenter, who usually resides at a lectern. A lecture is a “one-to-many” form of communication, involving little or no audience participation. It is authoritarian, by nature. For an information dump a lecture works fine. The development of engaging lecture activities requires a significant amount of instructor preparation and limits the time available to provide traditional lectures. However, the positive results of this study suggest the need for a restructuring of the plain classroom lecture to incorporate more engaging lectures to improve both the qualitative experiences and performance levels of students. Due to the fast changing society and modernization, there is also change in interest of the students learning styles, so the researchers conducted a study about the effect of educational software in teaching music. This research determined the effects of integrating e-media piano in teaching music at Santiago National High School. Specifically, it dealt with the following: the pretest result of the control and experimental group, the post-test of the two groups; and the significant difference between the pretest and posttest results of the two groups. The input of the study was determined by administering the researcher-made test which is the principal tool for gathering the needed data. The gathered data underwent statistical treatments such as mean, standard deviation, t-test for independent means and t-test for dependent means. A pretest was administered from the two study groups before the conduct of the experiment; this is to determine if the groups were equally comparable in terms of intellectual ability. The validated and reliability teacher-made test is composed of twenty-five (25) items. This covered topics about the different elements of music such as melody, tempo, dynamics, rhythm, pitch, harmony, texture, and timbre. Moreover, both groups were given posttest after the experimental period had been conducted. The same 25 multiple choice item tests was given to the experimental and control group to find out if the use of E- Media piano software had an effect to the students’ performance in music. Nevertheless, the latter was superior than the former. Thus, the effectiveness of E-media is notable, enhancing the learners’ capacity for acquisition and retention of information. The integration of e-media piano software to traditional classroom instruction may be encouraged. Educational software specifically designed to fit the learning objectives can be used as motivation, enrichment activity, and as an assessment tool to classroom instruction. The active participation and interest that educational software may provide to the teaching and learning process should be exploited. Educational software made and developed appropriately to the level of the learners may be adopted not only in music but in the other components of M.A.P.E.H as well. Other strategies which may integrate other trends articulated with the interest of today’s learners may also be adapted as exposing students to modernized school can achieve a quality education and can produce lifelong learning

    Vitamin D and Systemic Lupus Erythematosus: Bones, Muscles, and Joints

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    Vitamin D3, or cholecalciferol, is the naturally occurring form of vitamin D that is converted in the skin and hydroxylated in the liver and kidney to the active form found in humans. The main role for vitamin D is calcium homeostasis, and low levels of vitamin D result in lower gastrointestinal absorption of calcium. Vitamin D is also critical for mineralization of bone tissue, muscle function, and coordination. Recent studies have found prevention of bone mass loss and reduction in falls and fractures in patients supplemented with vitamin D. A high percentage of systemic lupus erythematosus patients are reported to have insufficient or deficient levels of vitamin D. This paper reviews the biology of vitamin D, its role in calcium homeostasis, and how it contributes to the maintenance of bone, muscle, and joint function in older adults and individuals with systemic lupus erythematosus

    Effect of vitamin D supplementation on bone health parameters of healthy young Indian women

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    Summary There is a huge prevalence of hypovitaminosis D in the Indian population. We studied the efficacy and safety of oral vitamin D supplementation in apparently healthy adult women. Monthly cholecalciferol given orally, 60,000 IU/month during summers and 120,000 IU/month during winters, safely increases 25-hydroxyvitamin D (25 (OH)D) levels to near normal levels. Introduction There is a huge burden of hypovitaminosis D in the Indian population. The current recommendation for vitamin D supplementation is not supported by sufficient evidence. Methods Study subjects included 100 healthy adult women of reproductive age group from hospital staff. They wer

    Efficacy of different doses and time intervals of oral vitamin D supplementation with or without calcium in elderly nursing home residents

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    Summary: The effect of equivalent oral doses of vitamin D3 600 IU/day, 4200 IU/week and 18,000 IU/month on vitamin D status was compared in a randomized clinical trial in nursing home residents. A daily dose was more effective than a weekly dose, and a monthly dose was the least effective. Introduction: It is assumed that equivalent daily, weekly or monthly doses of vitamin D3 equally influence vitamin D status. This was investigated in a randomized clinical trial in nursing home residents. Methods: The study was performed in ten nursing homes including 338 subjects (76 male and 262 female), with a mean age of 84 (± SD 6.3 years). They received oral vitamin D3 either 600 IU/day, or 4200 IU/week, or 18,000 IU/month or placebo. After 4 months, calcium was added during 2 weeks, 320 mg/day or 640 mg/day or placebo. Outcome: serum levels of 25-hydroxyvitamin D (25(OH)D), parathyroid hormone (PTH) and bone turnover markers. Statistical approach: linear multilevel analysis. Results: At baseline, mean serum 25(OH)D was 25.0 nmol/L (SD 10.9), and in 98%, it was lower than 50 nmol/L. After 4 months, mean serum 25(OH)D levels increased to 62.5 nmol/L (after daily vitamin D3 69.9 nmol/L, weekly 67.2 nmol/L and monthly 53.1 nmol/L, P<0.001 between groups). Median serum PTH levels decreased by 23% (p<0.001). Bone turnover markers did not decrease. Calcium supplementation had no effect on serum PTH and bone turnover. Conclusion: Daily vitamin D was more effective than weekly, and monthly administration was the least effective. © 2007 International Osteoporosis Foundation and National Osteoporosis Foundation

    Female asylum seekers with musculoskeletal pain: the importance of diagnosis and treatment of hypovitaminosis D

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    BACKGROUND: Hypovitaminosis D is well known in different populations, but may be under diagnosed in certain populations. We aim to determine the first diagnosis considered, the duration and resolution of symptoms, and the predictors of response to treatment in female asylum seekers suffering from hypovitaminosis D. METHODS: Design: A pre- and post-intervention observational study. Setting: A network comprising an academic primary care centre and nurse practitioners. Participants: Consecutive records of 33 female asylum seekers with complaints compatible with osteomalacia and with hypovitaminosis D (serum 25-(OH) vitamin D <21 nmol/l). Treatment intervention: The patients received either two doses of 300,000 IU intramuscular cholecalciferol as well as 800 IU of cholecalciferol with 1000 mg of calcium orally, or the oral treatment only. Main outcome measures: We recorded the first diagnosis made by the physicians before the correct diagnosis of hypovitaminosis D, the duration of symptoms before diagnosis, the responders and non-responders to treatment, the duration of symptoms after treatment, and the number of medical visits and analgesic drugs prescribed 6 months before and 6 months after diagnosis. Tests: Two-sample t-tests, chi-squared tests, and logistic regression analyses were performed. Analyses were performed using SPSS 10.0. RESULTS: Prior to the discovery of hypovitaminosis D, diagnoses related to somatisation were evoked in 30 patients (90.9%). The mean duration of symptoms before diagnosis was 2.53 years (SD 3.20). Twenty-two patients (66.7%) responded completely to treatment; the remaining patients were considered to be non-responders. After treatment was initiated, the responders' symptoms disappeared completely after 2.84 months. The mean number of emergency medical visits fell from 0.88 (SD 1.08) six months before diagnosis to 0.39 (SD 0.83) after (P = 0.027). The mean number of analgesic drugs that were prescribed also decreased from 1.67 (SD 1.5) to 0.85 (SD 1) (P = 0.001). CONCLUSION: Hypovitaminosis D in female asylum seekers may remain undiagnosed, with a prolonged duration of chronic symptoms. The potential pitfall is a diagnosis of somatisation. Treatment leads to a rapid resolution of symptoms, a reduction in the use of medical services, and the prescription of analgesic drugs in this vulnerable population

    Optimal Use of Vitamin D When Treating Osteoporosis

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    Inadequate serum 25-hydroxyvitamin D (25[OH]D) concentrations are associated with muscle weakness, decreased physical performance, and increased propensity in falls and fractures. This paper discusses several aspects with regard to vitamin D status and supplementation when treating patients with osteoporosis in relation to risks and prevention of falls and fractures. Based on evidence from literature, adequate supplementation with at least 700 IU of vitamin D, preferably cholecalciferol, is required for improving physical function and prevention of falls and fractures. Additional calcium supplementation may be considered when dietary calcium intake is below 700 mg/day. For optimal bone mineral density response in patients treated with antiresorptive or anabolic therapy, adequate vitamin D and calcium supplementation is also necessary. Monitoring of 25(OH)D levels during follow-up and adjustment of vitamin D supplementation should be considered to reach and maintain adequate serum 25(OH)D levels of at least 50 nmol/L, preferably greater than 75 nmol/L in all patients

    Low wintertime vitamin D levels in a sample of healthy young adults of diverse ancestry living in the Toronto area: associations with vitamin D intake and skin pigmentation

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    <p>Abstract</p> <p>Background</p> <p>Vitamin D plays a critical role in bone metabolism and many cellular and immunological processes. Recent research indicates that concentrations of serum 25-hydroxyvitamin D [25(OH)D], the main indicator of vitamin D status, should be in excess of 75 nmol/L. Low levels of 25(OH)D have been associated with several chronic and infectious diseases. Previous studies have reported that many otherwise healthy adults of European ancestry living in Canada have low vitamin D concentrations during the wintertime. However, those of non-European ancestry are at a higher risk of having low vitamin D levels. The main goal of this study was to examine the vitamin D status and vitamin D intake of young Canadian adults of diverse ancestry during the winter months.</p> <p>Methods</p> <p>One hundred and seven (107) healthy young adults self-reporting their ancestry were recruited for this study. Each participant was tested for serum 25(OH)D concentrations and related biochemistry, skin pigmentation indices and basic anthropometric measures. A seven-day food diary was used to assess their vitamin D intake. An ANOVA was used to test for significant differences in the variables among groups of different ancestry. Linear regression was employed to assess the impact of relevant variables on serum 25(OH)D concentrations.</p> <p>Results</p> <p>More than 93% of the total sample had concentrations below 75 nmol/L. Almost three-quarters of the subjects had concentrations below 50 nmol/L. There were significant differences in serum 25(OH)D levels (p < 0.001) and vitamin D intake (p = 0.034) between population groups. Only the European group had a mean vitamin D intake exceeding the current Recommended Adequate Intake (RAI = 200 IU/day). Total vitamin D intake (from diet and supplements) was significantly associated with 25(OH)D levels (p < 0.001). Skin pigmentation, assessed by measuring skin melanin content, showed an inverse relationship with serum 25(OH)D (p = 0.033).</p> <p>Conclusion</p> <p>We observe that low vitamin D levels are more prevalent in our sample of young healthy adults than previously reported, particularly amongst those of non-European ancestry. Major factors influencing 25(OH)D levels were vitamin D intake and skin pigmentation. These data suggest a need to increase vitamin D intake either through improved fortification and/or supplementation.</p
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