Showing papers by "Nova Southeastern University published in 2008"

Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook

Abstract: Since the early 1980s, episodes of coral reef bleaching and mortality, due primarily to climate-induced ocean warming, have occurred almost annually in one or more of the world's tropical or subtropical seas. Bleaching is episodic, with the most severe events typically accompanying coupled ocean–atmosphere phenomena, such as the El Nino-Southern Oscillation (ENSO), which result in sustained regional elevations of ocean temperature. Using this extended dataset (25+ years), we review the short- and long-term ecological impacts of coral bleaching on reef ecosystems, and quantitatively synthesize recovery data worldwide. Bleaching episodes have resulted in catastrophic loss of coral cover in some locations, and have changed coral community structure in many others, with a potentially critical influence on the maintenance of biodiversity in the marine tropics. Bleaching has also set the stage for other declines in reef health, such as increases in coral diseases, the breakdown of reef framework by bioeroders, and the loss of critical habitat for associated reef fishes and other biota. Secondary ecological effects, such as the concentration of predators on remnant surviving coral populations, have also accelerated the pace of decline in some areas. Although bleaching severity and recovery have been variable across all spatial scales, some reefs have experienced relatively rapid recovery from severe bleaching impacts. There has been a significant overall recovery of coral cover in the Indian Ocean, where many reefs were devastated by a single large bleaching event in 1998. In contrast, coral cover on western Atlantic reefs has generally continued to decline in response to multiple smaller bleaching events and a diverse set of chronic secondary stressors. No clear trends are apparent in the eastern Pacific, the central-southern-western Pacific or the Arabian Gulf, where some reefs are recovering and others are not. The majority of survivors and new recruits on regenerating and recovering coral reefs have originated from broadcast spawning taxa with a potential for asexual growth, relatively long distance dispersal, successful settlement, rapid growth and a capacity for framework construction. Whether or not affected reefs can continue to function as before will depend on: (1) how much coral cover is lost, and which species are locally extirpated; (2) the ability of remnant and recovering coral communities to adapt or acclimatize to higher temperatures and other climatic factors such as reductions in aragonite saturation state; (3) the changing balance between reef accumulation and bioerosion; and (4) our ability to maintain ecosystem resilience by restoring healthy levels of herbivory, macroalgal cover, and coral recruitment. Bleaching disturbances are likely to become a chronic stress in many reef areas in the coming decades, and coral communities, if they cannot recover quickly enough, are likely to be reduced to their most hardy or adaptable constituents. Some degraded reefs may already be approaching this ecological asymptote, although to date there have not been any global extinctions of individual coral species as a result of bleaching events. Since human populations inhabiting tropical coastal areas derive great value from coral reefs, the degradation of these ecosystems as a result of coral bleaching and its associated impacts is of considerable societal, as well as biological concern. Coral reef conservation strategies now recognize climate change as a principal threat, and are engaged in efforts to allocate conservation activity according to geographic-, taxonomic-, and habitat-specific priorities to maximize coral reef survival. Efforts to forecast and monitor bleaching, involving both remote sensed observations and coupled ocean–atmosphere climate models, are also underway. In addition to these efforts, attempts to minimize and mitigate bleaching impacts on reefs are immediately required. If significant reductions in greenhouse gas emissions can be achieved within the next two to three decades, maximizing coral survivorship during this time may be critical to ensuring healthy reefs can recover in the long term.

International society of sports nutrition position stand: nutrient timing.

Abstract: Position Statement: The position of the Society regarding nutrient timing and the intake of carbohydrates, proteins, and fats in reference to healthy, exercising individuals is summarized by the following eight points: 1.) Maximal endogenous glycogen stores are best promoted by following a high-glycemic, high-carbohydrate (CHO) diet (600 – 1000 grams CHO or ~8 – 10 g CHO/kg/d), and ingestion of free amino acids and protein (PRO) alone or in combination with CHO before resistance exercise can maximally stimulate protein synthesis. 2.) During exercise, CHO should be consumed at a rate of 30 – 60 grams of CHO/hour in a 6 – 8% CHO solution (8 – 16 fluid ounces) every 10 – 15 minutes. Adding PRO to create a CHO:PRO ratio of 3 – 4:1 may increase endurance performance and maximally promotes glycogen re-synthesis during acute and subsequent bouts of endurance exercise. 3.) Ingesting CHO alone or in combination with PRO during resistance exercise increases muscle glycogen, offsets muscle damage, and facilitates greater training adaptations after either acute or prolonged periods of supplementation with resistance training. 4.) Post-exercise (within 30 minutes) consumption of CHO at high dosages (8 – 10 g CHO/kg/day) have been shown to stimulate muscle glycogen re-synthesis, while adding PRO (0.2 g – 0.5 g PRO/kg/day) to CHO at a ratio of 3 – 4:1 (CHO: PRO) may further enhance glycogen re-synthesis. 5.) Post-exercise ingestion (immediately to 3 h post) of amino acids, primarily essential amino acids, has been shown to stimulate robust increases in muscle protein synthesis, while the addition of CHO may stimulate even greater levels of protein synthesis. Additionally, pre-exercise consumption of a CHO + PRO supplement may result in peak levels of protein synthesis. 6.) During consistent, prolonged resistance training, post-exercise consumption of varying doses of CHO + PRO supplements in varying dosages have been shown to stimulate improvements in strength and body composition when compared to control or placebo conditions. 7.) The addition of creatine (Cr) (0.1 g Cr/kg/day) to a CHO + PRO supplement may facilitate even greater adaptations to resistance training. 8.) Nutrient timing incorporates the use of methodical planning and eating of whole foods, nutrients extracted from food, and other sources. The timing of the energy intake and the ratio of certain ingested macronutrients are likely the attributes which allow for enhanced recovery and tissue repair following high-volume exercise, augmented muscle protein synthesis, and improved mood states when compared with unplanned or traditional strategies of nutrient intake.

Safety issues associated with commercially available energy drinks

Abstract: Objective To describe benefits and adverse effects associated with the consumption of energy drinks. Data sources Searches were conducted using Medline, IPA (International Pharmaceutical Abstracts), EMBASE, and MANTIS; databases such as Natural Medicines Comprehensive Database, Natural Standard, ALTMEDEX, and AltHealthWatch; and Google (range 1980 to September 2007). Search terms included energy drink, Red Bull, caffeine, glucose, ginseng, guarana, taurine , and bitter orange. Data synthesis Most energy drinks contain natural products such as guarana, ginseng, and taurine. As much as 80 to 300 mg of caffeine and 35 grams of processed sugar per 8-ounce serving are commonly present in energy drinks such as Cocaine, Pimp Juice, Red Bull, and Spike Shooter. No reports were identified of negative effects associated with taurine, ginseng, and guarana used in the amounts found in most energy drinks. Commonly reported adverse effects seen with caffeine in the quantities present in most energy drinks are insomnia, nervousness, headache, and tachycardia. Four documented case reports of caffeine-associated deaths were found, as well as four separate cases of seizures associated with the consumption of energy drinks. Conclusion The amounts of guarana, taurine, and ginseng found in popular energy drinks are far below the amounts expected to deliver either therapeutic benefits or adverse events. However, caffeine and sugar are present in amounts known to cause a variety of adverse health effects.

Maintaining the integrity of the enamel surface: the role of dental biofilm, saliva and preventive agents in enamel demineralization and remineralization.

Abstract: Background Dental caries is an infectious disease, and it affects 90 percent of late adolescents and young adults in the United States. It is a complex disease that occurs along the interface between the dental biofilm and the enamel surface. Results Many components in saliva are taken up by dental biofilm and protect the enamel surface. On the other hand, newly erupted teeth depend on the enamel pellicle for posteruption maturation of acid-susceptible substituted hydroxyapatite. When Streptococcus mutans colonizes dental biofilm, it depends on vertical transmission, horizontal transmission or both. These acidogenic, aciduric bacteria are considered to be the primary organisms responsible for enamel caries. The ability of the biofilm to sequester calcium, phosphate and fluoride from the saliva, as well as from sources outside the oral cavity allows enamel to undergo remineralization after demineralization. Optimal remineralization depends on the enamel surface's being exposed to low concentrations of calcium, phosphate and fluoride for prolonged periods. Outside sources of bioavailable calcium, phosphate and fluoride can alter dental biofilm's cariogenicity. Clinical Implications The use of sugar alcohols, povidone-iodine, delmopinol, triclosan and chlorhexidine may modulate the caries process. In addition, studies involving probiotics and molecular genetics have provided results showing that these methods can replace and displace cariogenic bacteria with noncariogenic bacteria, while maintaining normal oral homeostasis.

Suicide methods in Europe: a gender-specific analysis of countries participating in the “European Alliance Against Depression”

Abstract: Objective: To identify the most frequent gender-specific suicide methods in Europe. Design: Proportions of seven predominant suicide methods utilised in 16 countries participating in the European Alliance Against Depression (EAAD) were reported in total and cross-nationally. Relative risk (RR) relating to suicide methods and gender was calculated. To group countries by pattern of suicide methods, hierarchical clustering was applied. Setting and participants: Data on suicide methods for 119 122 male and 41 338 female cases in 2000–4/5 from 16 EAAD countries, covering 52% of European population were obtained. Results: Hanging was the most prevalent suicide method among both males (54.3%) and females (35.6%). For males, hanging was followed by firearms (9.7%) and poisoning by drugs (8.6%); for females, by poisoning by drugs (24.7%) and jumping from a high place (14.5%). Only in Switzerland did hanging rank as second for males after firearms. Hanging ranked first among females in eight countries, poisoning by drugs in five and jumping from a high place in three. In all countries, males had a higher risk than females of using firearms and hanging and a lower risk of poisoning by drugs, drowning and jumping. Grouping showed that countries might be divided into five main groups among males; for females, grouping did not yield clear results. Conclusions: Research on suicide methods could lead to the development of gender-specific intervention strategies. Nevertheless, other approaches, such as better identification and treatment of mental disorders and the improvement of toxicological aid should be put in place.

Rhizomatic Education: Community as Curriculum

Abstract: The truths of which the masses now approve are the very truths that the fighters at the outposts held to in the days of our grandfathers. We fighters at the outposts nowadays no longer approve of them; and I do not believe there is any other well-ascertained truth except this, that no community can live a healthy life if it is nourished only on such old marrowless truths. —Henrik Ibsen, An Enemy of the People (1882/2000, IV.i)

Satisfaction, quality and value and effects on repurchase and positive word‐of‐mouth behavioral intentions in a B2B services context

Abstract: Purpose – The aim of this article is to provide an understanding of how satisfaction, quality, and value affect repurchase and positive word‐of‐mouth in a business‐to‐business (B2B) setting. Most previous studies in this area apply to business‐to‐consumer (B2C) situations.Design/methodology/approach – A survey of 382 users of freight services was undertaken in the USA. An exploratory pilot study was undertaken to gain a better understanding of these users and to test the research instrument. Structural equation modeling was used to test the constructs.Findings – The results showing the best‐fit model identified a number of relationships that were unexpected. These are discussed in detail.Practical implications – Managers have a model, survey instrument and methodology that service firms can use to establish what they are doing right or wrong to retain customers. Managers are also given guidelines on how to increase customer satisfaction in B2B services.Originality/value – This paper deals with these const...

Epalrestat: an aldose reductase inhibitor for the treatment of diabetic neuropathy.

Abstract: Diabetic neuropathy is one of the most common long-term complications in patients with diabetes mellitus, with a prevalence of 60-70% in the United States. Treatment options include antidepressants, anticonvulsants, tramadol, and capsaicin. These agents are modestly effective for symptomatic relief, but they do not affect the underlying pathology nor do they slow progression of the disease. Epalrestat is an aldose reductase inhibitor that is approved in Japan for the improvement of subjective neuropathy symptoms, abnormality of vibration sense, and abnormal changes in heart beat associated with diabetic peripheral neuropathy. Unlike the current treatment options for diabetic neuropathy, epalrestat may affect or delay progression of the underlying disease process. Data from experimental studies indicate that epalrestat reduces sorbitol accumulation in the sciatic nerve, erythrocytes, and ocular tissues in animals, and in erythrocytes in humans. Data from six clinical trials were evaluated, and it was determined that epalrestat 50 mg 3 times/day may improve motor and sensory nerve conduction velocity and subjective neuropathy symptoms as compared with baseline and placebo. Epalrestat is well tolerated, and the most frequently reported adverse effects include elevations in liver enzyme levels and gastrointestinal-related events such as nausea and vomiting. Epalrestat may serve as a new therapeutic option to prevent or slow the progression of diabetic neuropathy. Long-term, comparative studies in diverse patient populations are needed for clinical application.

Future Learning Landscapes: Transforming Pedagogy through Social Software

Abstract: In both mainstream society and education, Web 2.0 has inspired intense and growing interest, particularly as wikis, weblogs (blogs), really simple syndication (RSS) feeds, social networking sites, tag-based folksonomies, and peer-to-peer media-sharing applications have gained traction in all sectors of the education industry (Allen 2004; Alexander 2006). Also referred to as the "Read-Write Web” (Richardson 2006) because it goes beyond the one-way provision of downloadable content by allowing users to become contributors, Web 2.0 allows customization, personalization, and rich opportunities for networking and collaboration, all of which offer considerable potential for addressing the needs of today's diverse student body (Bryant 2006).

Clinometric properties of the six-minute walk test in individuals undergoing rehabilitation poststroke.

Abstract: The 6-minute walk test (6MWT) is commonly used to measure walking ability. The purpose of this study was to determine the test-retest reliability and concurrent and construct validity of the 6MWT in patients who were actively undergoing inpatient rehabilitation poststroke. Thirty-seven patients undergoing inpatient rehabilitation after a stroke participated; mean age was 66.3 years and mean time since stroke was 33.7 days. Patients underwent two 6MWT trials with 1-3 days between trials. Additional outcome measures taken were gait speed and the Functional Independence Measure (FIM). The 6MWT exhibited high test-retest reliability; ICC(2,1) 0.973 (95% CI=0.925-0.988) and a minimal detectable change (MDC(90)) of 54.1 m. The 6MWT was strongly to moderately correlated with gait speed (r=0.89), locomotion (walk) FIM (r=0.69), and motor FIM (r=0.52). The 6MWT is a clinically useful measure of walking ability poststroke. It is reliable and is related to other measures of walking ability and function that are commonly used during rehabilitation after stroke.

Mutations in SPG11 are frequent in autosomal recessive spastic paraplegia with thin corpus callosum, cognitive decline and lower motor neuron degeneration.

Abstract: Hereditary spastic paraplegias (HSP) are neurodegenerative diseases mainly characterized by lower limb spasticity associated, in complicated forms, with additional neurological signs. We have analysed a large series of index patients (n = 76) with this condition, either from families with an autosomal recessive inheritance (n = 43) or isolated patients (n = 33), for mutations in the recently identified SPG11 gene. We found 22 truncating mutations, including the first four splice-site mutations, segregating in seven isolated cases and 13 families. Nineteen mutations were novel. Two recurrent mutations were found in Portuguese and North-African patients indicating founder effects in these populations. The mutation frequency varied according to the phenotype, from 41%, in HSP patients presenting with a thin corpus callosum (TCC) visualized by MRI, to 4.5%, in patients with mental impairment without a TCC. Disease onset occurred during the first to the third decade mainly by problems with gait and/or mental retardation. After a mean disease duration of 14.9 +/- 6.6 years, the phenotype of 38 SPG11 patients was severe with 53% of patients wheelchair bound or bedridden. In addition to mental retardation, 80% of the patients showed cognitive decline with executive dysfunction. Interestingly, the phenotype also frequently included lower motor neuron degeneration (81%) with wasting (53%). Slight ocular cerebellar signs were also noted in patients with long disease durations. In addition to a TCC (95%), brain MRI revealed white matter alterations (69%) and cortical atrophy (81%), which worsened with disease duration. In conclusion, our study reveals the high frequency of SPG11 mutations in patients with HSP, a TCC and cognitive impairment, including in isolated patients, and extends the associated phenotype.

Updated recommendations for managing the care of patients receiving oral bisphosphonate therapy: an advisory statement from the American Dental Association Council on Scientific Affairs.

Abstract: Background and Overview In 2005, the American Dental Association (ADA) Council on Scientific Affairs convened an expert panel to develop clinical recommendations for dentists treating patients who are receiving oral bisphosphonate therapy. The Journal of the American Dental Association published the resulting report in 2006. This 2008 advisory statement is the first of projected periodic updates of the 2006 clinical recommendations. Conclusion This 2008 advisory statement concludes, on the basis of a review of the current literature, that for patients receiving bisphosphonate therapy, the risk of developing bisphosphonate-associated osteonecrosis (BON) of the jaw apparently remains low. It also newly concludes that current screening and diagnostic tests are unreliable for predicting a patient's risk of developing the condition. This statement updates the 2006 recommendations regarding general dentistry, management of periodontal diseases, implant placement and maintenance, oral and maxillofacial surgery, endodontics, restorative dentistry and prosthodontics, and orthodontics.

Scope, Completeness, and Accuracy of Drug Information in Wikipedia

Abstract: Background:With the advent of Web 2.0 technologies, user-edited online resources such as Wikipedia are increasingly tapped for information. However, there is little research on the quality of health information found in Wikipedia.Objective:To compare the scope, completeness, and accuracy of drug information in Wikipedia with that of a free, online, traditionally edited database (Medscape Drug Reference [MDR]).Methods:Wikipedia and MDR were assessed on 8 categories of drug information. Questions were constructed and answers were verified with authoritative resources, Wikipedia and MDR were evaluated according to scope (breadth of coverage) and completeness. Accuracy was tracked by factual errors and errors of omission. Descriptive statistics were used to summarize the components. Fisher's exact test was used to compare scope and paired Student's Most was used to compare current results in Wikipedia with entries 90 days prior to the current access.Results:Wikipedia was able to answer significantly fewer dru...

A cross‐cultural examination of relationship strength in B2B services

Abstract: Purpose – The purpose of this paper is to specify and test factors surrounding relationship strength between buyers and suppliers in a global, business‐to‐business (B2B) services context In so doing, the paper helps extend relationship marketing theories to this under‐researched domainDesign/methodology/approach – A literature review, along with results of field interviews and surveys, provide a conceptual framework for the relationship strength formation process in the context of multi‐cultures The research then tests a model of hypothesized relationships using structural equation modelingFindings – The paper confirms the influence of perceived value, switching costs and relationship quality (satisfaction, trust and affective commitment) on relationship strength As predicted, relationship quality mediates the influence that perceived value has on relationship strength Switching costs further mediate the influence that relationship quality has on relationship strength which, in turn, influences subs

Effects of Sevelamer Hydrochloride and Calcium Carbonate on Renal Osteodystrophy in Hemodialysis Patients

Abstract: Disturbances in mineral metabolism play a central role in the development of renal bone disease. In a 54-wk, randomized, open-label study, 119 hemodialysis patients were enrolled to compare the effects of sevelamer hydrochloride and calcium carbonate on bone. Biopsy-proven adynamic bone disease was the most frequent bone abnormality at baseline (59%). Serum phosphorus, calcium, and intact parathyroid hormone were well controlled in both groups, although calcium was consistently lower and intact parathyroid hormone higher among patients who were randomly assigned to sevelamer. Compared with baseline values, there were no changes in mineralization lag time or measures of bone turnover (e.g., activation frequency) after 1 yr in either group. Osteoid thickness significantly increased in both groups, but there was no significant difference between them. Bone formation rate per bone surface, however, significantly increased from baseline only in the sevelamer group (P = 0.019). In addition, of those with abnormal microarchitecture at baseline (i.e., trabecular separation), seven of 10 in the sevelamer group normalized after 1 yr compared with zero of three in the calcium group. In summary, sevelamer resulted in no statistically significant changes in bone turnover or mineralization compared with calcium carbonate, but bone formation increased and trabecular architecture improved with sevelamer. Further studies are required to assess whether these changes affect clinical outcomes, such as rates of fracture.

LMO2 Protein Expression Predicts Survival in Patients With Diffuse Large B-Cell Lymphoma Treated With Anthracycline-Based Chemotherapy With and Without Rituximab

Abstract: Purpose The heterogeneity of diffuse large B-cell lymphoma (DLBCL) has prompted the search for new markers that can accurately separate prognostic risk groups. We previously showed in a multivariate model that LMO2 mRNA was a strong predictor of superior outcome in DLBCL patients. Here, we tested the prognostic impact of LMO2 protein expression in DLBCL patients treated with anthracycline-based chemotherapy with or without rituximab. Patients and Methods DLBCL patients treated with anthracycline-based chemotherapy alone (263 patients) or with the addition of rituximab (80 patients) were studied using immunohistochemistry for LMO2 on tissue microarrays of original biopsies. Staining results were correlated with outcome. Results In anthracycline-treated patients, LMO2 protein expression was significantly correlated with improved overall survival (OS) and progression-free survival (PFS) in univariate analyses (OS, P = .018; PFS, P = .010) and was a significant predictor independent of the clinical Internatio...

Immediate and early loading of Straumann implants with a chemically modified surface (SLActive) in the posterior mandible and maxilla: 1-year results from a prospective multicenter study

Abstract: Objective: Immediate and early loading of implants can simplify treatment and increase patient satisfaction. This 3-year randomized-controlled trial will therefore evaluate survival rates and bone-level changes with immediately and early loaded Straumann implants with the SLActive surface. Material and methods: Partially edentulous patients ≥18 years of age were enrolled. Patients received a temporary restoration (single crown or two to four unit fixed partial denture) out of occlusal contact either immediately (immediate loading) or 28–34 days later (early loading group), with permanent restorations placed 20–23 weeks after surgery. The primary endpoint was change in crestal bone level from baseline (implant placement) to 12 months; the secondary variables were implant survival and success rates. Results: A total of 383 implants (197 immediate and 186 early) were placed in 266 patients; 41.8% were placed in type III and IV bone. The mean patient age was 46.3±12.8 years. Four implants failed in the immediate loading group and six in the early loading group, giving implant survival rates of 98% and 97%, respectively (P=NS). There were no implant failures in type IV bone. The overall mean bone level change from baseline to 12 months was 0.77±0.93 mm (0.90±0.90 and 0.63±0.95 mm in the immediate and early groups, respectively; P<0.001). However, a significant difference in implantation depth between the two groups (P<0.0001) was found. After adjusting for this slight difference in initial surgical placement depth, time to loading no longer had a significant influence on bone-level change. Significant influence was found for: center (P<0.0001), implant length (P<0.05) and implant position (P<0.0001). Bone gain was observed in approximately 16% of implants. Conclusions: The results demonstrated that Straumann implants with the SLActive surface are safe and predictable when used in immediate and early loading procedures. Even in poor-quality bone, survival rates were comparable with those from conventional or delayed loading. The mean bone-level change was not deemed to be clinically significant and compared well with the typical bone resorption observed in conventional implant loading.

Pharmacovigilance and reporting oversight in US FDA fast-track process: bisphosphonates and osteonecrosis of the jaw.

Abstract: More than half of all serious adverse reactions are identified 7 or more years after a drug receives approval from the US Food and Drug Administration (FDA). In 2002, 9 months after the intravenous bisphosphonate zoledronic acid received regulatory approval for marketing, the FDA received reports of nine patients with cancer, who were treated with zoledronic acid, who unexpectedly developed osteonecrosis of the jaw. During the next 2 years, three oral surgeons described 104 patients with cancer with osteonecrosis of the jaw in the medical literature and identified intravenous bisphosphonate therapy as being common to the care of these patients. In subspecialty medical, radiology, and dental journals, case reports and case series described clinical features of osteonecrosis of the jaw in patients with cancer who were treated with bisphosphonates. Manufacturer-sponsored epidemiological studies reported the first estimates of the incidence of this toxic effect, ranging from 0.1% to 1.8%. By contrast, independent epidemiological efforts from clinicians and the International Myeloma Foundation reported incidence estimates between 5% and 10%. Between 2003 and 2005, warnings about the risks of bisphosphonate-associated osteonecrosis were disseminated by national regulatory agencies, the manufacturers of bisphosphonates, and the International Myeloma Foundation. From 2006, independent clinical recommendations for diagnosis, prevention, and treatment of this toxic effect have been disseminated by manufacturers, national regulatory authorities, the International Myeloma Foundation, and medical specialty organisations. Furthermore, independent efforts by pharmaceutical manufacturers, dental and medical professionals, a non-profit organisation (the International Myeloma Foundation), patients, and regulatory authorities has led to the rapid identification and dissemination of safety information for this serious adverse reaction. Better coordination of safety-related pharmacovigilance initiatives is now needed.

Light curing of resin-based composites in the LED era.

Abstract: This review thoroughly accumulated information regarding new technologies for state-of-the-art light curing of resin composite materials. Visible light cured resin-based composites allow the dentist to navigate the initiation of the polymerization step for each layer being applied. Curing technology was regularly subjected to changes during the last decades, but meanwhile the LED era is fully established. Today, four main polymerization types are available, i.e. halogen bulbs, plasma are lamps, argon ion lasers, and light emitting diodes. Additionally, different curing protocols should help to improve photopolymerization in terms of less stress being generated. Conclusions were: (1) with high-power LED units of the latest generation, curing time of 2 mm thick increments of resin composite can be reduced to 20 seconds to obtain durable results; (2) curing depth is fundamentally dependent on the distance of the resin composite to the light source, but only decisive when exceeding 6 mm; (3) polymerization kinetics can be modified for better marginal adaptation by softstart polymerization; however, in the majority of cavities this may not be the case; (4) adhesives should be light-cured separately for at least 10 seconds when resin composite is applied directly; (5) photocuring through indirect restorations such as ceramics is still a problem, therefore, both dual-cured adhesives and dual-cured composites and resin coating in any way are recommended; and (6) heat generation with high-power photopolymerization units should not be underestimated as a biological problem for both gingival and pulpal tissues.

Learning at a Distance: Engaged or Not?

Abstract: Distance learning is the fastest growing segment of postsecondary education. Almost 3 million students took at least one online course in fall 2005, an increase of more than 800,000 over the previous year (Allen and Seaman 2006). At the same time, questions persist about the quality of online learning. In one recent study, about two-fifths of senior academic officers at U.S. degree-granting higher education institutions expressed a belief that distance learning is inferior to face-to-face learning (Allen and Seaman 2006). Although some studies show that distance education learners benefit from their experiences to the same degree as campus-based learners (Dutton, Dutton, and Perry 2002; Neuhauser 2002), most of the work demonstrating positive outcomes in distance learning has focused on older students, who are often more motivated and have the self-discipline to manage effectively the unstructured nature of the distance learning environment (Dibiase 2000; Hardy and Boaz 1997).

Survival potential of Escherichia coli and Enterococci in subtropical beach sand: implications for water quality managers

Abstract: Fecal bacteria have traditionally been used as indicator organisms to monitor the quality of recreational waters. Recent work has questioned the robustness of traditional indicators, particularly at seawater bathing beaches. For example, a study of Florida beaches found unexpectedly high abundances of Escherichia coli, fecal coliforms, and enterococci in beach sand. The aim of the present study was to explain these abundances by assessing the survival of E. coli and enterococci in beach sand relative to seawater. We used a combination of quantitative laboratory mesocosm experiments and field observations. Results suggested that E. coli and enterococci exhibited increased survivability and growth in sand relative to seawater. Because fecal bacteria are capable of replicating in sand, at least under controlled laboratory conditions, the results suggest that sand may be an important reservoir of metabolically active fecal organisms. Experiments with "natural" mesocosms (i.e., unsterilized sand or water rich in micropredators and native bacteria) failed to show the same increases in fecal indicators as was found in sterile sand. It is postulated that this was due to predation and competition with indigenous bacteria in these "natural" systems. Nonetheless, high populations of indicators were maintained and recovered from sand over the duration of the experiment as opposed to the die-off noted in water. Indicator bacteria may wash out of sand into shoreline waters during weather and tidal events, thereby decreasing the effectiveness of these indicators as predictors of health risk and complicating the interpretations for water quality managers.

Termite digestomes as sources for novel lignocellulases

Abstract: For most animals, lignocellulose is a nutritionally poor food source that is highly resistant to enteric degradation. Termites, however, have the unique ability to digest lignocellulose with high efficiency, often using it as a sole food source. Another interesting aspect of termite biology is their symbiotic associations with prokaryotic and eukaryotic gut symbionts. Termite symbionts contribute to lignocellulose digestion efficiency, but by no means are they responsible for 100% of lignocellulose digestion in the termite gut. The termite digestome can be defined as the pool of genes, both termite and symbiont, that contribute to lignocellulose depolymerization and digestion, as well as simple sugar fermentation, nutrient transport, and nutrient assimilation. A central goal of termite digestomics research is to define/understand the relative contributions of termite and symbiont gene products to collaborative lignocellulose digestion. While efficient microbial cellulases have already been identified and are presently being used in industrial applications, efficient and inexpensive pre-treatments for lignin and hemicellulose depolymerization are not yet well developed. In this respect, termite digestomics has already offered significant insights, and can continue to identify relevant enzymes, as well as reveal how to optimally combine and utilize these enzymes for maximum synergy. The topics covered in this review are as follows: lignocellulose structure with emphasis on its potential for depolymerization by termite and gut endosymbiont-derived digestive enzymes; termite biology and ecology from the perspectives of termite nutrition, gut physiology, and lignocellulose digestion; and trends identified through recent termite digestomics research. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd

Empirical study of relationship value in industrial services

Abstract: Purpose – The purpose of this paper is to assist industrial service providers in building relationships that maximize value to their customers. The study aims to add to relationship value research by examining its dimensions, antecedents, outcomes, and cross‐culture relevance.Design/methodology/approach – Using structural equation modeling, the study examines the influence that relationship value has on commitment and intentions, as well as the determinants of value encompassing the core offering, sourcing process and buyer operations. The sample covers 42 countries for cross‐cultural perspectives.Findings – By understanding the factors creating relationship value, providers are more likely to build enduring relationships with their buyers. Findings confirm that commitment and intentions are influenced by relationship value, which, in turn, is impacted by benefits such as performance, efficiency, and reliability as well as comparative costs and switching costs.Research limitations/implications – The study...

Automatic Associations and Panic Disorder: Trajectories of Change over the Course of Treatment.

Abstract: Cognitive models of anxiety and panic suggest that symptom reduction during treatment should be preceded by changes in cognitive processing, including modifying the anxious schema. The current study tests these hypotheses by using a repeated measures design to evaluate whether the trajectory of change in automatic panic associations over the course of 12-week cognitive behavior therapy (CBT) is related to the trajectory of change in panic symptoms. Individuals with panic disorder (N=43) completed a measure of automatic panic associations (the Implicit Association Test, which reflects elements of the schema construct) every three weeks over the course of therapy, and measures of panic symptoms each week. Dynamic bivariate latent difference score modeling indicated that automatic panic associations not only changed over the course of CBT for panic disorder, but showed these changes were correlated with symptom reduction. Moreover, change in automatic panic associations was a significant predictor of change in panic symptom severity. These findings permit inferences about the temporality of change, suggesting that cognitive change does in fact precede and contribute to symptom change.