Sequence of ossification in the skeleton of growing and metamorphosing tadpoles of Rana pipiens

The order of ossification of bones in the skeleton of Rana pipiens during larval growth and metamorphosis has been determined from observations on specimens fixed in 70% alcohol and stained with alizarin red S. The axial skeleton ossifies in a generally cephalo-caudal sequence, beginning with the parasphenoid bone at Taylor-Kollros stages IV-IX, followed by vertebrae (V-IX) and then the urostyle (IX-XIV). Exoccipitals (VII-IX), frontoparietals (XI-XII) and prootics (XIII-XVII) are additional cranial bones which successively ossify before metamorphosis. With the onset of metamorphosis at stage XVIII jawbones and rostral bones of the skull ossify in the following succession: premaxilla, maxilla, septomaxilla, nasal, dentary, angular, squamosal, pterygoid, prevomer, mentomeckelian, quadratojugal, palatine, columella, posteromedial process of “hyoid.” The sphenethmoid does not ossify until after metamorphosis. Ossification of limbbones begins with the femur or humerus at stages X-XII and progresses proximo-distally to the phalanges by stages XIII-XV. Carpals, however, do not ossify until stage XXV or after metamorphosis. The ilium of the pelvic girdle begins to ossify at stages X-XII, but the ischium is delayed until stages XX-XXIII. Scapula and coracoid of the pectoral girdle undergo initial ossification at stages XII-XIV, suprascapula and clavicle at stages XIII-XV. The sternum does not begin to ossify until stage XXIV. The possible role of thyroid hormones in stimulating osteogenesis is discussed.Supported by research grants from the National Science Foundation (GB 4317) and the U. S. Public Health Service (GM 05867-10).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50254/1/1051290404_ftp.pd

Justifying reimbursement for Alzheimers diagnostics and treatments: Seeking alignment on evidence

pre-printThe increasing cost of health care combined with expensive new drugs and diagnostics is leading to more frequent gaps between regulatory and reimbursement approval decisions. As a result, persons with Alzheimer's disease may have difficulty accessing the benefits of medical advances. In contrast to the long history and established structure for drug approval, payer decision-making is dispersed, not standardized and perspectives on necessary evidence differ and often poorly defined. Particularly challenging is how to demonstrate the value of drugs and diagnostics for patients who do not yet have significant functional decline. While discussions to develop consensus continue, clinical trials should begin to incorporate health system and patient-oriented outcomes. In some situations additional studies designed to demonstrate value and comparative effectiveness will be needed. Such studies should examine outcomes of representative populations in community settings. To assure scientific advances in diagnosis and treatment benefit patients, developing evidence to support reimbursement will become as important as obtaining regulatory approval

A Comparative Study Of Online Retailing: U.S. Vs. E.U. Consumer Attitudes Toward Product Country Of Origin

As a first-mover into the use of the Internet for e-commerce, many U.S. retailers have found another tool that it has added to the plethora of methods it can use to reach customers.  Although in an early stage of development, the growth of e-commerce is likely to mushroom.  Trailing the U.S. in Internet marketing, retailers in the European Union (E.U.) are quickly realizing its potential to increase revenues and profits.  This study focuses on two aspects of online retailing by contrasting the perceptions of U.S. and E.U. consumers on the use of the Internet for shopping, and contrasting their views with respect to where a product originates.  The study surveyed 268 people from either the U.S., E.U., and from a handful of other locations.  From the gathered data set findings and conclusions were made that should be of interest to professionals in academe or the commercial business sector

Increased Calcium Intake Does Not Suppress Circulating 1,25-Dihydroxyvitamin D in Normocalcemic Patients with Sarcoidosis

Ca absorption is regulated by 1,25(OH)2D, and serum values vary inversely with Ca intake. In sarcoidosis, 1,25(OH)2D is produced by alveolar macrophages in response to y-interferon, and patients may develop hypercalcemia after prolonged exposure to sunlight and increased dermal production of vitamin D3. To determine if increased Ca intake suppresses serum 1,25(OH)2D in normocalcemic patients and to identify those at risk, 17 normal subjects and 11 patients were studied on a metabolic ward for two and one-half days while receiving first 400 and then 1,000 mg/d of Ca. On the low Ca intake, serum angiotensin-converting enzyme (ACE), an index of disease activity, was higher in only three of the patients than in the controls, mean serum 1,25(OH)2D was higher in the patients, and mean serum total Ca, serum Ca , and urinary Ca were not different in the two groups. On the higher Ca intake, mean urinary Ca increased in both groups, but mean serum 1,25(OH)2D was suppressed only in the normal subjects. Thus, 1,25(OH)2D production is abnormally regulated, indicating that (a) normocalcemic patients with sarcoidosis are at risk for developing abnormal Ca metabolism, and (b) a better index of disease activity is provided by the oral Ca suppression test than by serum ACE. (J. Clin. Invest. 1993. 91:1396- 1398.

Schopenhauer's Understanding of Schelling

Schopenhauer is famously abusive toward his philosophical contemporary and rival, Friedrich William Joseph von Schelling. This chapter examines the motivations for Schopenhauer’s immoderate attitude and the substance behind the insults. It looks carefully at both the nature of the insults and substantive critical objections Schopenhauer had to Schelling’s philosophy, both to Schelling’s metaphysical description of the thing-in-itself and Schelling’s epistemic mechanism of intellectual intuition. It concludes that Schopenhauer’s substantive criticism is reasonable and that Schopenhauer does in fact avoid Schelling’s errors: still, the vehemence of the abuse is best perhaps explained by the proximity of their philosophies, not the distance. Indeed, both are developing metaphysics of will with full and conflicted awareness of the Kantian epistemic strictures against metaphysics. In view of this, Schopenhauer is particularly concerned to mark his own project as legitimate by highlighting the manner in which he avoids Schelling’s errors

International collaborative investigation of beginning seventh grade students' understandings of scientific inquiry

Although understanding of scientific inquiry is included in science education reform documents around the world, little is known about what students have learned about inquiry during their elementary school years. This is partially due to the lack of any assessment instrument to measure understandings about scientific inquiry. However, a valid and reliable assessment has recently been developed and published, Views About Scientific Inquiry (VASI). The purpose of this large scale international project was to get the first baseline data on what beginning middle school students have learned. The participating countries for this symposium are: Brazil, China, Israel, South Africa, Spain, and Sweden. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation. This baseline data will simultaneously provide information on what, if anything, students learn about inquiry in elementary school, as well as their beginning knowledge as they enter secondary school. A concerted effort was made to provide a relatively representative picture of each country

Knowledge about inquiry : a study in South African high schools

This paper reports a study on South African learners‟ knowledge about scientific inquiry using the Views About Scientific Inquiry (VASI) questionnaire. The sample consisted of 105 grade 11 learners from 7 schools across the socio-economic spectrum in a South African city. A rubric for scoring the VASI questionnaire was developed and refined during the process of coding and is presented. Results showed that the learners held more informed views than that reported in previous international studies, except for particularly naive views regarding multiple methods of investigation. The results are discussed in terms of the Revised National Curriculum Statement (RNCS) that was taught from 2003 to 2010 in South African schools. This curriculum was founded on outcomes based principles, valuing process skills rather than content. The study found that examples provided in the RNCS document correspond closely to the aspects of inquiry as described by the National Research Council (NRC). It is argued that the RNCS contributed to the more informed views about inquiry found amongst South African learners in this study.http://www.tandfonline.com/loi/tsed202015-09-30hb201

he efects of cooperative learning strategies to develop fluency in 9th grade students at Guillermo Cano National institute in the first school term, 2019. Diploma thesis, Universidad Nacional Autónoma de Nicaragua, Managua.

This study is focused on the importance of implementing cooperative learning strategies for developing fluency of the English language on 9th grade students at Guillermo Cano National Institute. Therefore researchers formulated two main questions based on research objectives to guide it: What type of cooperative learning strategies should be applied for students to develop fluency in the English class? How do cooperative learning strategies contribute to develop the students´ fluency? This research follows a qualitative design and aims at presenting new strategies that will be useful for English teachers and productive for students. We identified which strategies are the most effective in the English class and can be applied by English teacher in Nicaraguan classrooms. Firstly, students of 9th grade can develop better communication through fluency with the implementation of cooperative learning in the learning process. Secondly, students' performance improved significantly and they developed good attitude toward learning English via cooperative learning. Thirdly, when using cooperative learning students are motivated and less reluctant. Therefore, this study recommends the adoption of cooperative learning as a strategy fluency development in English Learning speaking in particular. Key words: fluency, cooperative learning and strategies

The efects of cooperative learning strategies to develop fluency in 9th grade students at Guillermo Cano National institute in the first school term, 2019

This study is focused on the importance of implementing cooperative learning strategies for developing fluency of the English language on 9th grade students at Guillermo Cano National Institute. Therefore researchers formulated two main questions based on research objectives to guide it: What type of cooperative learning strategies should be applied for students to develop fluency in the English class? How do cooperative learning strategies contribute to develop the students´ fluency? This research follows a qualitative design and aims at presenting new strategies that will be useful for English teachers and productive for students. We identified which strategies are the most effective in the English class and can be applied by English teacher in Nicaraguan classrooms. Firstly, students of 9th grade can develop better communication through fluency with the implementation of cooperative learning in the learning process. Secondly, students' performance improved significantly and they developed good attitude toward learning English via cooperative learning. Thirdly, when using cooperative learning students are motivated and less reluctant. Therefore, this study recommends the adoption of cooperative learning as a strategy fluency development in English Learning speaking in particular