Showing papers by "University of Miami published in 2004"

The oceanic sink for anthropogenic CO2.

Abstract: Using inorganic carbon measurements from an international survey effort in the 1990s and a tracer-based separation technique, we estimate a global oceanic anthropogenic carbon dioxide (CO2) sink for the period from 1800 to 1994 of 118 19 petagrams of carbon. The oceanic sink accounts for48% of the total fossil-fuel and cement-manufacturing emissions, implying that the terrestrial biosphere was a net source of CO 2 to the atmosphere of about 39 28 petagrams of carbon for this period. The current fraction of total anthropogenic CO2 emissions stored in the ocean appears to be about one-third of the long-term potential. Since the beginning of the industrial period in the late 18th century, i.e., over the anthropocene (1), humankind has emitted large quantities of CO2 into the atmosphere, mainly as a result of fossil-fuel burning, but also because of land-use practices, e.g., deforestation (2). Measurements and reconstructions of the atmospheric CO2 history reveal, however, that less than half of these emissions remain in the atmosphere (3). The anthropogenic CO2 that did not accumulate in the atmosphere must have been taken up by the ocean, by the land biosphere, or by a combination of both. The relative roles of the ocean and land biosphere as sinks for anthropogenic CO2 over the anthropocene are currently not known. Although the anthropogenic CO2 budget for the past two decades, i.e., the 1980s and 1990s, has been investigated in detail (3), the estimates of the ocean sink have not been based on direct measurements of changes in the oceanic inventory of dissolved inorganic carbon (DIC). Recognizing the need to constrain the oceanic uptake, transport, and storage of anthropogenic CO 2 for the anthropocene and to provide a baseline for future estimates of oceanic CO 2 uptake, two international ocean research programs, the World Ocean Circulation Experiment (WOCE) and the Joint Global Ocean Flux Study (JGOFS), jointly conducted a comprehensive survey of inorganic carbon distributions in the global ocean in the 1990s (4). After completion of the U.S. field program in 1998, a 5-year effort was begun to compile and rigorously quality-control the U.S. and international data sets, in

Impact of Anthropogenic CO2 on the CaCO3 System in the Oceans

Abstract: Rising atmospheric carbon dioxide (CO 2 ) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed the saturation state ofthe oceans with respect to calcium carbonate (CaCO3) particles. Here we estimate the in situ CaCO3 dissolution rates for the global oceans from total alkalinity and chlorofluorocarbon data, and we also discuss the future impacts of anthropogenic CO2 on CaCO3 shell– forming species. CaCO 3 dissolution rates, ranging from 0.003 to 1.2 micromoles per kilogram per year, are observed beginning near the aragonite saturation horizon. The total water column CaCO 3 dissolution rate for the global oceans is approximately 0.5 0.2 petagrams ofCaCO 3-C per year, which is approximately 45 to 65% ofthe export production ofCaCO 3 . Atmospheric CO 2 concentrations oscillated be

Ecosystem-Based Fishery Management

Abstract: Ecosystem-based fishery management (EBFM) is a new direction for fishery management, essentially reversing the order of management priorities so that management starts with the ecosystem rather than a target species. EBFM aims to sustain healthy marine ecosystems and the fisheries they support. Pikitch et al . describe the potential benefits of implementation of EBFM that, in their view, far outweigh the difficulties of making the transition from a management system based on maximizing individual species.

A global ocean carbon climatology: Results from Global Data Analysis Project (GLODAP)

Abstract: [1] During the 1990s, ocean sampling expeditions were carried out as part of the World Ocean Circulation Experiment (WOCE), the Joint Global Ocean Flux Study (JGOFS), and the Ocean Atmosphere Carbon Exchange Study (OACES). Subsequently, a group of U.S. scientists synthesized the data into easily usable and readily available products. This collaboration is known as the Global Ocean Data Analysis Project (GLODAP). Results were merged into a common format data set, segregated by ocean. For comparison purposes, each ocean data set includes a small number of high-quality historical cruises. The data were subjected to rigorous quality control procedures to eliminate systematic data measurement biases. The calibrated 1990s data were used to estimate anthropogenic CO2, potential alkalinity, CFC watermass ages, CFC partial pressure, bomb-produced radiocarbon, and natural radiocarbon. These quantities were merged into the measured data files. The data were used to produce objectively gridded property maps at a 1° resolution on 33 depth surfaces chosen to match existing climatologies for temperature, salinity, oxygen, and nutrients. The mapped fields are interpreted as an annual mean distribution in spite of the inaccuracy in that assumption. Both the calibrated data and the gridded products are available from the Carbon Dioxide Information Analysis Center. Here we describe the important details of the data treatment and the mapping procedure, and present summary quantities and integrals for the various parameters.

Designing for Older Adults: Principles and Creative Human Factors Approaches

Abstract: Winner of the 2019 Richard M. Kalish Innovative Publication Book Award 2019 – Gerontological Society of America This new edition provides easily accessible and usable guidelines for practitioners in the design community for older adults. It includes an updated overview of the demographic characteristics of older adult populations and the scientific knowledge base of the aging process relevant to design. New chapters include Existing and Emerging Technologies, Work and Volunteering, Social Engagement, and Leisure Activities. Also included is basic information on user-centered design and specific recommendations for conducting research with older adults. Features Focuses on design for diverse groups of older adults Introduces the latest scientific advances, but is easily accessible to practitioners and students Offers an emphasis on existing and emerging technologies within everyday contexts and activities Includes many examples of everyday activities and contexts, as well as new chapters Presents a new conceptual model linking design principles across a broad range of topics

Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery

Abstract: background The proportion of women who attempt vaginal delivery after prior cesarean delivery has decreased largely because of concern about safety The absolute and relative risks associated with a trial of labor in women with a history of cesarean delivery, as compared with elective repeated cesarean delivery without labor, are uncertain

Neonatal adaptive immunity comes of age

Abstract: The past decade has brought great strides in our understanding of adaptive immunity in neonatal mice. Although poor immune responses are commonly observed, it is now clear that mature function can be achieved by all arms of the adaptive immune system. An ever-increasing body of evidence indicates that the neonatal period of life is a unique developmental stage in which responses are highly plastic and dependent on the conditions of antigen exposure. This review focuses on our new understanding in mice and, where it is clear that related phenomena occur, in humans.

Diabetic Somatic Neuropathies

Abstract: ropathic pain (7–10), and this and other putative mechanisms will be discussed The clinical features, diagnosis, and management of the focal and multifocal neuropathies will be described A major portion of this review will discuss the clinical features, assessment, and management of the patient with the most common form of DN, diabetic distal sensory polyneuropathy (DPN) The late sequelae of DPN and their prevention will also be described Finally, practical guidelines for the screening of DPN in clinical practice will be provided For further details on this topic, please refer to recent reviews (11– 18)

Tolerance, not immunity, crucially depends on IL-2.

Abstract: Interleukin-2 (IL-2) was identified based on its potent T-cell growth-factor activity and is widely considered to be a key cytokine in T-cell-dependent immune responses. However, the main non-redundant activity of this cytokine centres on the regulation of T-cell tolerance, and recent studies indicate that a failure in the production of CD4(+)CD25(+) regulatory T cells is the underlying cause of autoimmunity in the absence of IL-2. In marked contrast to the importance of IL-2 in peripheral T-cell tolerance, T-cell immunity is readily elicited to various agents in the absence of IL-2 in vivo. Here, we discuss these findings and, in particular, the action of IL-2 on regulatory T cells and effector cells, and the targeting of IL-2 and/or the IL-2 receptor in clinical settings.

On the limiting aerodynamic roughness of the ocean in very strong winds

Abstract: The aerodynamic friction between air and sea is an important part of the momentum balance in the development of tropical cyclones. Measurements of the drag coefficient, relating the tangential stress ( frictional drag) between wind and water to the wind speed and air density, have yielded reliable information in wind speeds less than 20 m/s ( about 39 knots). In these moderate conditions it is generally accepted that the drag coefficient ( or equivalently, the aerodynamic roughness'') increases with the wind speed. Can one merely extrapolate this wind speed tendency to describe the aerodynamic roughness of the ocean in the extreme wind speeds that occur in hurricanes ( wind speeds greater than 30 m/s)? This paper attempts to answer this question, guided by laboratory extreme wind experiments, and concludes that the aerodynamic roughness approaches a limiting value in high winds. A fluid mechanical explanation of this phenomenon is given.

Removing the Shadow of Suspicion: The Effects of Apology Versus Denial for Repairing Competence- Versus Integrity-Based Trust Violations

Abstract: Two studies were conducted to examine the implications of an apology versus a denial for repairing trust after an alleged violation. Results reveal that trust was repaired more successfully when mistrusted parties (a) apologized for violations concerning matters of competence but denied culpability for violations concerning matters of integrity, and (b) had apologized for violations when there was subsequent evidence of guilt but had denied culpability for violations when there was subsequent evidence of innocence. Supplementary analyses also revealed that the interactive effects of violation type and violation response on participants' trusting intentions were mediated by their trusting beliefs. Combined, these findings provide needed insight and supporting evidence concerning how trust might be repaired in the aftermath of a violation.

B cell depletion as a novel treatment for systemic lupus erythematosus: A phase I/II dose-escalation trial of rituximab

Abstract: Objective Safer and more effective therapies are needed for the treatment of systemic lupus erythematosus (SLE). B lymphocytes have been shown to play fundamental pathogenic roles in SLE, and therefore, elimination of B cells with the use of rituximab may represent a new therapy for SLE. Methods A phase I/II dose-escalation trial of rituximab added to ongoing therapy in SLE was conducted. Rituximab was administered as a single infusion of 100 mg/m2 (low dose), a single infusion of 375 mg/m2 (intermediate dose), or as 4 infusions (1 week apart) of 375 mg/m2 (high dose). CD19+ lymphocytes were measured to determine the effectiveness of B cell depletion. The Systemic Lupus Activity Measure (SLAM) score was used as the primary outcome for clinical efficacy. Results Rituximab was well tolerated in this patient population, with most experiencing no significant adverse effects. Only 3 serious adverse events, which were thought to be unrelated to rituximab administration, were noted. A majority of patients (11 of 17) had profound B cell depletion (to <5 CD19+ B cells/μl). In these patients, the SLAM score was significantly improved at 2 and 3 months compared with baseline (P = 0.0016 and P = 0.0022, respectively, by paired t-test). This improvement persisted for 12 months, despite the absence of a significant change in anti–double-stranded DNA antibody and complement levels. Six patients developed human antichimeric antibodies (HACAs) at a level ≥100 ng/ml. These HACA titers were associated with African American ancestry, higher baseline SLAM scores, reduced B cell depletion, and lower levels of rituximab at 2 months after initial infusion. Conclusion Rituximab therapy appears to be safe for the treatment of SLE and holds significant therapeutic promise, at least for the majority of patients experiencing profound B cell depletion. Based on these results, controlled trials of rituximab appear to be warranted.

Coral reefs: corals' adaptive response to climate change

Abstract: The long-term response of coral reefs to climate change depends on the ability of reef-building coral symbioses to adapt or acclimatize to warmer temperatures, but there has been no direct evidence that such a response can occur. Here we show that corals containing unusual algal symbionts that are thermally tolerant and commonly associated with high-temperature environments are much more abundant on reefs that have been severely affected by recent climate change. This adaptive shift in symbiont communities indicates that these devastated reefs could be more resistant to future thermal stress, resulting in significantly longer extinction times for surviving corals than had been previously assumed.

Closing the gap: Addressing the vocabulary needs of English‐language learners in bilingual and mainstream classrooms

Abstract: Gaps in reading performance between Anglo and Latino children are associated with gaps in vocabulary knowledge. An intervention was designed to enhance fifth graders' academic vocabulary. The meanings of academically useful words were taught together with strategies for using information from context, from morphology, from knowledge about multiple meanings, and from cognates to infer word meaning. Among the principles underlying the intervention were that new words should be encountered in meaningful text, that native Spanish speakers should have access to the text's meaning through Spanish, that words should be encountered in varying contexts, and that word knowledge involves spelling, pronunciation, morphology, and syntax as well as depth of meaning. Fifth graders in the intervention group showed greater growth than the comparison group on knowledge of the words taught, on depth of vocabulary knowledge, on understanding multiple meanings, and on reading comprehension. The intervention effects were as large for the English-language learners (ELLs) as for the English-only speakers (EOs), though the ELLs scored lower on all pre- and posttest measures. The results show the feasibility of improving comprehension outcomes for students in mixed ELL-EO classes, by teaching word analysis and vocabulary learning strategies.

Sequential therapies for proliferative lupus nephritis

Abstract: Background Long-term therapy with cyclophosphamide enhances renal survival in patients with proliferative lupus nephritis; however, the beneficial effect of cyclophosphamide must be weighed against its considerable toxic effects. Methods Fifty-nine patients with lupus nephritis (12 in World Health Organization class III, 46 in class IV, and 1 in class Vb) received induction therapy consisting of a maximum of seven monthly boluses of intravenous cyclophosphamide (0.5 to 1.0 g per square meter of body-surface area) plus corticosteroids. Subsequently, the patients were randomly assigned to one of three maintenance therapies: quarterly intravenous injections of cyclophosphamide, oral azathioprine (1 to 3 mg per kilogram of body weight per day), or oral mycophenolate mofetil (500 to 3000 mg per day) for one to three years. The base-line characteristics of the three groups were similar, with the exception that the chronicity index was 1.9 points lower in the cyclophosphamide group than in the mycophenolate mofe...

Marrow-isolated adult multilineage inducible (MIAMI) cells, a unique population of postnatal young and old human cells with extensive expansion and differentiation potential.

Abstract: We report here the isolation of a population of non-transformed pluripotent human cells from bone marrow after a unique expansion/selection procedure. This procedure was designed to provide conditions resembling the in vivo microenvironment that is home for the most-primitive stem cells. Marrow-adherent and -nonadherent cells were co-cultured on fibronectin, at low oxygen tension, for 14 days. Colonies of small adherent cells were isolated and further expanded on fibronectin at low density, low oxygen tension with 2% fetal bovine serum. They expressed high levels of CD29, CD63, CD81, CD122, CD164, hepatocyte growth factor receptor (cMet), bone morphogenetic protein receptor 1B (BMPR1B), and neurotrophic tyrosine kinase receptor 3 (NTRK3) and were negative for CD34, CD36, CD45, CD117 (cKit) and HLADR. The embryonic stem cell markers Oct-4 and Rex-1, and telomerase were expressed in all cultures examined. Cell-doubling time was 36 to 72 hours, and cells have been expanded in culture for more than 50 population doublings. This population of cells was consistently isolated from men and women of ages ranging from 3- to 72-years old. Colonies of cells expressed numerous markers found among embryonic stem cells as well as mesodermal-, endodermal- and ectodermal-derived lineages. They have been differentiated to bone-forming osteoblasts, cartilage-forming chondrocytes, fat-forming adipocytes and neural cells and to attachment-independent spherical clusters expressing genes associated with pancreatic islets. Based on their unique characteristics and properties, we refer to them as human marrow-isolated adult multilineage inducible cells, or MIAMI cells. MIAMI cells proliferate extensively without evidence of senescence or loss of differentiation potential and thus may represent an ideal candidate for cellular therapies of inherited or degenerative diseases.

cAMP and Schwann cells promote axonal growth and functional recovery after spinal cord injury

Abstract: Central neurons regenerate axons if a permissive environment is provided; after spinal cord injury, however, inhibitory molecules are present that make the local environment nonpermissive. A promising new strategy for inducing neurons to overcome inhibitory signals is to activate cAMP signaling. Here we show thatcAMP levels fall in the rostral spinal cord, sensorimotor cortex and brainstem after spinal cord contusion. Inhibition of cAMP hydrolysis by the phosphodiesterase IV inhibitor rolipram prevents this decrease and when combined with Schwann cell grafts promotes significant supraspinal and proprioceptive axon sparing and myelination. Furthermore, combining rolipram with an injection of db-cAMP near the graft not only prevents the drop in cAMP levels but increases them above those in uninjured controls. This further enhances axonal sparing and myelination, promotes growth of serotonergic fibers into and beyond grafts, and significantly improves locomotion. These findings show that cAMP levels are key for protection, growth and myelination of injured CNS axons in vivo and recovery of function.

Clarifying the Construct of Mindfulness in the Context of Emotion Regulation and the Process of Change in Therapy

Abstract: Bishop et al. (this issue) propose an operational definition of mindfulness developed by a recent consensus panel. The group provides a solid empirical framework from which to develop measures of mindfulness, and they propose an exciting research agenda. We describe measurement development work from our research group that provides initial support for the proposed consensus definition and that examines mindfulness in relation to emotion regulation variables. We extend the discussion by describing how mindfulness can enhance the stabilizing and destabilizing aspects of therapeutic change, and we illustrate this in the context of our treatment program for depression.

CHIP and Hsp70 regulate tau ubiquitination, degradation and aggregation

Abstract: Molecular chaperones, ubiquitin ligases and proteasome impairment have been implicated in several neurodegenerative diseases, including Alzheimer's and Parkinson's disease, which are characterized by accumulation of abnormal protein aggregates (e.g. tau and alpha-synuclein respectively). Here we report that CHIP, an ubiquitin ligase that interacts directly with Hsp70/90, induces ubiquitination of the microtubule associated protein, tau. CHIP also increases tau aggregation. Consistent with this observation, diverse of tau lesions in human postmortem tissue were found to be immunopositive for CHIP. Conversely, induction of Hsp70 through treatment with either geldanamycin or heat shock factor 1 leads to a decrease in tau steady-state levels and a selective reduction in detergent insoluble tau. Furthermore, 30-month-old mice overexpressing inducible Hsp70 show a significant reduction in tau levels. Together these data demonstrate that the Hsp70/CHIP chaperone system plays an important role in the regulation of tau turnover and the selective elimination of abnormal tau species. Hsp70/CHIP may therefore play an important role in the pathogenesis of tauopathies and also represents a potential therapeutic target.

Negative Affects Deriving From the Behavioral Approach System

Abstract: Does the behavioral approach system (BAS) relate to the experience of any negative affects, or are all negative affects tied to the behavioral inhibition system (BIS)? In Study 1, self-reported Fun Seeking predicted reports of greater frustration and sadness after frustrative nonreward. In Study 2, self-reported Reward Responsiveness predicted reports of greater anger in response to scenarios. In Study 3, self-reported Drive predicted reports of greater anger after the terrorist attacks of September 11, 2001. In no case did BIS sensitivity contribute uniquely to these affects, though BIS predicted nervousness in Study 2 and fear in Study 3. Discussion focuses on the role of frustration and anger in effortful pursuit of goals and depressed affect in disengagement from goals.

Variation in sexual reproduction in orchids and its evolutionary consequences: a spasmodic journey to diversification

Abstract: The great taxonomic diversity of the Orchidaceae is often attributed to adaptive radiation for specific pollinators driven by selection for outcrossing. However, when one looks beyond the product to the process, the evidence for selection is less than overwhelming. We explore this problem by discussing relevant aspects of orchid biology and asking which aspects of reproduction explain the intricate pollination mechanisms and diversification of this family. We reaffirm that orchids are primarily pollination limited, the severity of which is affected by resource constraints. Fruit set is higher in temperate than in tropical species, and in species which offer pollinator rewards than those that do not. Reproductive success is skewed towards few individuals in a population and effective population sizes are often small. Population structure, reproductive success and gene flow among populations suggest that in many situations genetic drift may be as important as selection in fostering genetic and morphological variation in this family. Although there is some evidence for a gradualist model of evolutionary change, we believe that the great diversity in this family is largely a consequence of sequential and rapid interplay between drift and natural selection. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 84, 1–54.

Southern Ocean Iron Enrichment Experiment: Carbon Cycling in High- and Low-Si Waters

Abstract: The availability of iron is known to exert a controlling influence on biological productivity in surface waters over large areas of the ocean and may have been an important factor in the variation of the concentration of atmospheric carbon dioxide over glacial cycles. The effect of iron in the Southern Ocean is particularly important because of its large area and abundant nitrate, yet iron-enhanced growth of phytoplankton may be differentially expressed between waters with high silicic acid in the south and low silicic acid in the north, where diatom growth may be limited by both silicic acid and iron. Two mesoscale experiments, designed to investigate the effects of iron enrichment in regions with high and low concentrations of silicic acid, were performed in the Southern Ocean. These experiments demonstrate iron's pivotal role in controlling carbon uptake and regulating atmospheric partial pressure of carbon dioxide.

The pathology of human spinal cord injury: defining the problems.

Abstract: This article reviews the pathology of human spinal cord injury (SCI), focusing on potential differences between humans and experimental animals, as well as on aspects that may have mechanistic or therapeutic relevance. Importance is placed on astrocyte and microglial reactions. These cells carry out a myriad of functions and we review the evidence that supports their beneficial or detrimental effects. Likewise, vascular responses and the role of inflammation and demyelination in the mechanism of SCI are reviewed. Lastly, schwannosis is discussed, highlighting its high frequency and potential role when designing therapeutic interventions. We anticipate that a better understanding of the pathological responses in the human will be useful to investigators in their studies on the pathogenesis and therapy of SCI.

Pathophysiology of Cerebral Ischemia and Brain Trauma: Similarities and Differences:

Abstract: Current knowledge regarding the pathophysiology of cerebral ischemia and brain trauma indicates that similar mechanisms contribute to loss of cellular integrity and tissue destruction. Mechanisms of cell damage include excitotoxicity, oxidative stress, free radical production, apoptosis and inflammation. Genetic and gender factors have also been shown to be important mediators of pathomechanisms present in both injury settings. However, the fact that these injuries arise from different types of primary insults leads to diverse cellular vulnerability patterns as well as a spectrum of injury processes. Blunt head trauma produces shear forces that result in primary membrane damage to neuronal cell bodies, white matter structures and vascular beds as well as secondary injury mechanisms. Severe cerebral ischemic insults lead to metabolic stress, ionic perturbations, and a complex cascade of biochemical and molecular events ultimately causing neuronal death. Similarities in the pathogenesis of these cerebral injuries may indicate that therapeutic strategies protective following ischemia may also be beneficial after trauma. This review summarizes and contrasts injury mechanisms after ischemia and trauma and discusses neuroprotective strategies that target both types of injuries.

Irinotecan Plus Gemcitabine Results in No Survival Advantage Compared With Gemcitabine Monotherapy in Patients With Locally Advanced or Metastatic Pancreatic Cancer Despite Increased Tumor Response Rate

Abstract: Purpose This phase III, randomized, open-label, multicenter study compared the overall survival associated with irinotecan plus gemcitabine (IRINOGEM) versus gemcitabine monotherapy (GEM) in patients with chemotherapy-naive, locally advanced or metastatic pancreatic cancer. Patients and Methods IRINOGEM patients received starting doses of gemcitabine 1,000 mg/m2 and irinotecan 100 mg/m2 given weekly for 2 weeks every 3-week cycle. GEM patients received gemcitabine 1,000 mg/m2 weekly for 7 of 8 weeks (induction) and then weekly for 3 of 4 weeks. The primary end point of the trial was survival. Secondary end points included tumor response, time to tumor progression (TTP), changes in CA 19-9, and safety. Results In each arm, 180 randomly assigned patients comprised the intent-to-treat population evaluated for efficacy; 173 IRINOGEM and 169 GEM patients were treated. Median survival times were 6.3 months for IRINOGEM (95% CI, 4.7 to 7.5 months) and 6.6 months for GEM (95% CI, 5.2 to 7.8 months; log-rank P = ....