Functional and nutritional value of the Chilean seaweeds Codium fragile,Gracilaria chilensis and Macrocystis pyrifera

The nutritional composition of the edible seaweeds Codium fragile, Gracilaria chilensis and Macrocystis pyrifera was determined, including amino acid and fatty acid contents along with tocol and carotenoid contents. The results indicated that the three algae C. fragile, G. chilensis and M. pyrifera showed a high range of protein contents (13.7–10.8%), amino acid contents (1879.6–1417.7 mg/100 g dry algae) and a low content in lipids (0.7–15.0%). The most abundant fatty acids in C. fragile and G. chilensis were linolenic, oleic, and linoleic acid. δ‐Tocopherol and α‐tocopherol (677.8 and 453.5 µg/g lipid, respectively) were found in C. fragile, while in G. chilensis and M. pyrifera, γ‐tocotrienol and α‐tocopherol (263.5 and 1327.7 µg/g lipid, respectively) were found. In addition, in C. fragile and G. chilensis β‐carotene was the principal carotenoid found (197.9 and 113.7 µg/g dry algae, respectively) compared with M. pyrifera (17.4 µg/g dry algae). The composition of macronutrients (minerals, carbohydrate‐type dietetic fiber, proteins; low in lipids) and micronutrients (essential amino acids, PUFA of balanced n‐6/n‐3 proportion, β‐carotene and α‐tocopherol as source of vitamins A and E), corroborate the nutritional and biological potential of the studied algae, which constitute useful raw materials for the development of diets or ingredients for human and animal nutrition.     

Active contours: Generalization of the snake mode

Abstract— Segmentation is one of the fundamental issues in the field of image processing and computer vision. Various approaches include differentiating an object in the image as a final goal or for further processing (medical diagnosis, surveillance, 3‐D reconstruction and more). Snakes, a model proposed by Kass, Witkin, and Terzopoulos in 1987, provides an efficient method for segmenting an object through the minimization of its energy. The advantage of snakes is in its ability to use high‐level data given by the algorithm operator, as opposed to other methods such as the Laplace technique. The snakes model inherently imposes strong constraints on a given image in order to successfully segment an object. In this paper, the use of adjustment methods is described, which allow us to generalize the snake model to a wider range of applications. Through the use of pre‐processing techniques, the model's constraints were softened. The main theoretical model and its use in facing a real life image is presented.     

An XRD,FTIR and TPD investigation of NO2 surface adsorption sites of δ, γ Al2O3 and barium supported δ, γ Al2O3

This work reviews the use of terpenes available from renewable resources in the fine chemicals industry. Different products and processes are discussed. Transformations of terpenes involving isomerization, hydration, condensation, hydroformylation, hydrogenation, cyclization, oxidation, rearrangement, and ring contraction/enlargement are routes to produce a variety of compounds of interest to the pharmaceutical, agrochemical, and flavors and fragrances industries.     

Pedagogical lurking: Student engagement in non-posting discussion behavior

This paper presents the results of a study of student non-posting participation behavior in two online classes. Most often active message is assessed and thus implicitly valued in online class discussion, but the act of writing messages is not the only factor that contributes to student learning. However, it is the most visible and easiest to measure. Students may engage in processes of reading and reflection on the discussion board, not leaving their mark; it is these acts that may be referred to as pedagogical lurking. In this study, students were asked to self-report their non-visible course activities, the reasons behind these activities and their perceived usefulness related to learning. Findings show that about half of the students felt that they learned through the online discussion experience, and that they believe both posting and reading messages contributed to their ability to learn. These students were likely to enter the discussion before posting to obtain a model for participation, and to return at a later time to check for replies and reflect. Students who participated solely to meet course requirements and who focused on posting messages more than reading messages had less positive impressions of the discussion activity’s impact on learning.     

Antiproteinuric effect of angiotensin-converting enzyme inhibition and C5b-9 urinary excretion in membranous glomerulonephritis

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors have an antiproteinuric effect in membranous glomerulonephritis (MGN). However, no studies have investigated whether this antiproteinuric effect is influenced by urinary C5b-9 excretion, a marker of immunological activity in this disease. METHODS: Eleven patients with biopsy-proven MGN were treated with captopril for 8 weeks. The evolution of several clinical and biochemical parameters, including 24-h urinary protein excretion was evaluated every 4 weeks. Urinary C5b-9 excretion was measured at the onset and at the end of captopril treatment. RESULTS: Patients with MGN had significantly higher C5b-9 excretions than a group of 14 healthy controls (89 +/- 23 vs 3.7 +/- 1.4 ng/mg UCr; P < 0.001). A significant correlation was found between urinary C5b-9 and the magnitude of proteinuria, both at the onset and at the end of treatment. After 8 weeks of captopril treatment, proteinuria had decreased from 8 +/- 1.8 to 5.2 +/- 1.3 g/day (P < 0.05). Four weeks after captopril discontinuation, proteinuria rose to 7.3 +/- 1.7 g/day (P < 0.05). A marked variability in the antiproteinuric response was observed, ranging from 0 to 85% with respect to baseline values. No correlation between decrease in proteinuria and baseline urinary C5b-9 levels was observed. Several patients with elevated urinary C5b-9 levels had captopril-induced decrease in proteinuria. CONCLUSIONS: ACE inhibition induces an antiproteinuric effect in patients with MGN. The urinary C5b-9 excretion does not predict the magnitude of this response.     

Effects of Historical Reasoning Instruction and Writing Strategy Mastery in Culturally and Academically Diverse Middle School Classrooms.

Seventy 8th-grade students (including talented writers, those with average ability, and students in need of special education services) participated in an integrated social studies and language arts unit designed to promote historical understandings and argumentative writing skills. The historical reasoning instruction lasted 12 days, and the writing instruction lasted 10 days. Students applied historical inquiry strategies when reading documents related to westward expansion and learned to plan argumentative essays related to each historical event. Results indicate that in comparison to 62 students in a control group who did not receive either form of instruction, students who demonstrated mastery of the target strategies during instruction wrote historically more accurate and more persuasive essays regardless of their initial learning profile. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of uncontrolled factors in a validated liquid chromatography-tandem mass spectrometry method question its use as a reference method for marine toxins: major causes for concern

Chromatographic techniques coupled to mass spectrometry is the method of choice to replace the mouse bioassay (MBA) to detect marine toxins. This paper evaluates the influence of different parameters such as toxin solvents, mass spectrometric detection method, mobile-phase-solvent brands and equipment on okadaic acid (OA), dinophysistoxin-1 (DTX-1), and dinophysistoxin-2 (DTX-2) quantification. In addition, the study compares the results obtained when a toxin is quantified against its own calibration curve and with the calibration curve of the other analogues. The experiments were performed by liquid chromatography (LC) and ultraperformance liquid chromatography (UPLC) with tandem mass spectrometry detection (MS/MS). Three acetonitrile brands and two toxin solvents were employed, and three mass spectrometry detection methods were checked. One method that contains the transitions for azaspiracid-1 (AZA-1), azaspiracid-2 (AZA-2), azaspiracid-3(AZA-3), gimnodimine (GYM), 13-desmethyl spirolide C (SPX-1), pectenotoxin-2 (PTX-2), OA, DTX-1, DTX-2, yessotoxin (YTX), homoYTX, and 45-OH-YTX was compared in both instruments. This method operated in simultaneous positive and negative ionization mode. The other two mass methods operated only in negative ionization mode, one contains transitions to detect DTX-1, OA DTX-2, YTX, homoYTX, and 45-OH-YTX and the other only the transitions for the toxins under study OA, DTX-1, and DTX-2. With dependence on the equipment and mobile phase used, the amount of toxin quantified can be overestimated or underestimated, up to 44% for OA, 46% for DTX-1, and 48% for DTX-2. In addition, when a toxin was quantified using the calibration curve of the other analogues, the toxin amount obtained is different. The maximum variability was obtained when DTX-2 was quantified using either OA or a DTX-1 calibration curve. In this case, the overestimation was up to 88% using the OA calibration curve and up to 204% using the DTX-1 calibration curve. In summary, the correct quantification of DSP toxins by MS detection depends on multiple factors. Since these factors are not taken into account in a validated protocol, these results question the convenience of having MS/MS as a reference method for protecting consumers of marine toxins, moreover if toxicity of each group is considered independently and total toxicity is not summed anymore as it is in the MBA.     

Health status measurement in Toxic Oil Syndrome

Toxic Oil Syndrome (TOS) is a previously unreported condition which affected more than 20,000 people in Spain in 1981 and whose natural history is unknown. In 1993-94, a stratified random sample of 1400 survivors was drawn to measure their health status through clinical examination and their self-perception of well-being through the Nottingham Health Profile Questionnaire (NHPQ). Two-thirds of the sample population responded; indirect estimates suggest that selection bias was limited. Clear and intermediate signs of neuropathy were found in one-fifth and one-half of the patients, respectively. One-fourth and one-sixth showed some degree of scleroderma and contractures. All conditions were more frequent in women than in men and in age >50 than in younger ages. Although no concurrent control group was included in the study, prevalences of these conditions are well above expectations and are largely attributable to TOS. NHPQ scores increased with age in both sexes up to age 50, after which they reached a plateau (with values around 48 in men and 62 in women). Scores were associated to the occurrence of peripheral neurological changes, contractures, and scleroderma-like conditions. A multivariate analysis indicated age, sex, and severity of neurological conditions as major determinants of the NHPQ scores. This overall pattern of findings is peculiar to TOS and differs from the typical post-disaster nonspecific syndrome.