Vertical and Horizontal Vegetation Structure across Natural and Modified Habitat Types at Mount Kilimanjaro

In most habitats, vegetation provides the main structure of the environment. This complexity can facilitate biodiversity and ecosystem services. Therefore, measures of vegetation structure can serve as indicators in ecosystem management. However, many structural measures are laborious and require expert knowledge. Here, we used consistent and convenient measures to assess vegetation structure over an exceptionally broad elevation gradient of 866–4550m above sea level at Mount Kilimanjaro, Tanzania. Additionally, we compared (human)-modified habitats, including maize fields, traditionally managed home gardens, grasslands, commercial coffee farms and logged and burned forests with natural habitats along this elevation gradient. We distinguished vertical and horizontal vegetation structure to account for habitat complexity and heterogeneity. Vertical vegetation structure (assessed as number, width and density of vegetation layers, maximum canopy height, leaf area index and vegetation cover) displayed a unimodal elevation pattern, peaking at intermediate elevations in montane forests, whereas horizontal structure (assessed as coefficient of variation of number, width and density of vegetation layers, maximum canopy height, leaf area index and vegetation cover) was lowest at intermediate altitudes. Overall, vertical structure was consistently lower in modified than in natural habitat types, whereas horizontal structure was inconsistently different in modified than in natural habitat types, depending on the specific structural measure and habitat type. Our study shows how vertical and horizontal vegetation structure can be assessed efficiently in various habitat types in tropical mountain regions, and we suggest to apply this as a tool for informing future biodiversity and ecosystem service studies.

From the heart of Israel : Jewish tales and types

by Bernard Drachman. Illustr. by A. Warshawsky

AMS-C14 analysis of graphite obtained with an Automated Graphitization Equipment (AGE III) from aerosol collected on quartz filters

AMS-14C applications often require the analysis of small samples. Such is the case of atmospheric aerosols where frequently only a small amount of sample is available. The ion beam physics group at the ETH, Zurich, has designed an Automated Graphitization Equipment (AGE III) for routine graphite production for AMS analysis from organic samples of approximately 1 mg. In this study, we explore the potential use of the AGE III for graphitization of particulate carbon collected in quartz filters. In order to test the methodology, samples of reference materials and blanks with different sizes were prepared in the AGE III and the graphite was analyzed in a MICADAS AMS (ETH) system. The graphite samples prepared in the AGE III showed recovery yields higher than 80% and reproducible 14C values for masses ranging from 50 to 300 lg. Also, reproducible radiocarbon values were obtained for aerosol filters of small sizes that had been graphitized in the AGE III. As a study case, the tested methodology was applied to PM10 samples collected in two urban cities in Mexico in order to compare the source apportionment of biomass and fossil fuel combustion. The obtained 14C data showed that carbonaceous aerosols from Mexico City have much lower biogenic signature than the smaller city of Cuernavaca.

Influence of two types of self-retaining retractors on multifidus muscle blood flow during dorsolateral thoracolumbar hemilaminectomy in dogs

OBJECTIVES To assess the influence of the use of Gelpi and Grevel retractors on multifidus muscle blood flow during hemilaminectomy, using a dorsolateral approach, for acute disc extrusion in dogs as measured by laser speckle contrast imaging (LSCI). METHODS Blood flow in the multifidus muscles was measured intra-operatively using LSCI prior to insertion of the retractors, immediately after hemilaminectomy and removal of the retractors, and after 10 minutes of lavage of the surgical site. Plasma creatine kinase levels were measured preoperatively and 12-24 hours postoperatively. RESULTS Muscular blood flow was significantly decreased following retraction and remained lower than initial values 10 minutes after lavage in all dogs. The decrease in blood flow was significantly greater with Gelpi retractors (n = 8) than with Grevel retractors (n = 10). No significant relation was found between the duration of retraction and postoperative changes in creatine kinase levels or blood flow. CLINICAL SIGNIFICANCE Findings in this study demonstrate a drop in blood flow within the multifidus muscles using the dorsolateral approach regardless of retractor type used. Gelpi retractors seem to have greater influence on muscular blood flow than Grevel retractors. Further studies are warranted to confirm this second finding.

Cessation of facial growth in subjects with short, average, and long facial types - Implications for the timing of implant placement

Placement of a single-tooth implant should be performed when a patient's facial growth has ceased. In this retrospective observational study, we evaluated if there was a difference in the timing of cessation of craniofacial growth in short, average, and long facial types. Based on the value of the angle between cranial base and mandibular plane (SN/MP angle), three groups comprising 48 subjects with short facial type (SF; SN/MP ≤28°), 77 with average facial type (AF; SN/MP ≥31.5° and ≤34.5°), and 44 with long facial type (LF; SN/MP ≥38°) were selected. Facial growth was assessed on lateral cephalograms taken at 15.4 years of age, and 2, 5, and 10 years later. Variables were considered to be stable when the difference between two successive measurements was less than 1 mm or 1°. We found no difference between facial types in the timing of cessation of facial growth. Depending on the variable, the mean age when variables became stable ranged from 18.0 years (Is-Pal in LF group) to 22.0 years (SN/MP in LF group). However, facial growth continued at the last follow-up in approximately 20% subjects. This study demonstrates that facial type is not associated with the timing of cessation of facial growth.

Evaluation of different types of enamel conditioning before application of a fissure sealant

The aim of the study was to compare fissure sealant quality after mechanical conditioning of erbium-doped yttrium aluminium garnet (Er:YAG) laser or air abrasion prior to chemical conditioning of phosphoric acid etching or of a self-etch adhesive. Twenty-five permanent molars were initially divided into three groups: control group (n = 5), phosphoric acid etching; test group 1 (n = 10), air abrasion; and test group 2, (n = 10) Er:YAG laser. After mechanical conditioning, the test group teeth were sectioned buccolingually and the occlusal surface of one half tooth (equal to one sample) was acid etched, while a self-etch adhesive was applied on the other half. The fissure system of each sample was sealed, thermo-cycled and immersed in 5% methylene dye for 24 h. Each sample was sectioned buccolingually, and one slice was analysed microscopically. Using specialized software microleakage, unfilled margin, sealant failure and unfilled area proportions were calculated. A nonparametric ANOVA model was applied to compare the Er:YAG treatment with that of air abrasion and the self-etch adhesive with phosphoric acid (α = 0.05). Test groups were compared to the control group using Wilcoxon rank sum tests (α = 0.05). The control group displayed significantly lower microleakage but higher unfilled area proportions than the Er:YAG laser + self-etch adhesive group and displayed significantly higher unfilled margin and unfilled area proportions than the air-abrasion + self-etch adhesive group. There was no statistically significant difference in the quality of sealants applied in fissures treated with either Er:YAG laser or air abrasion prior to phosphoric acid etching, nor in the quality of sealants applied in fissures treated with either self-etch adhesive or phosphoric acid following Er:YAG or air-abrasion treatment.

Context Aware e-Learning Objects and their Types from the Perspective of the Object-Oriented Paradigm

The contribution of this article demonstrates how to identify context-aware types of e-Learning objects (eLOs) derived from the subject domains. This perspective is taken from an engineering point of view and is applied during requirements elicitation and analysis relating to present work in constructing an object-oriented (OO), dynamic, and adaptive model to build and deliver packaged e-Learning courses. Consequently, three preliminary subject domains are presented and, as a result, three primitive types of eLOs are posited. These types educed from the subject domains are of structural, conceptual, and granular nature. Structural objects are responsible for the course itself, conceptual objects incorporate adaptive and logical interoperability, while granular objects congregate granular assets. Their differences, interrelationships, and responsibilities are discussed. A major design challenge relates to adaptive behaviour. Future research addresses refinement on the subject domains and adaptive hypermedia systems.

Human Rhinovirus Types and Association with Respiratory Symptoms During the First Year of Life.

Human rhinoviruses (HRV) cause respiratory infections and are associated with asthma development. We assessed HRV prevalence, types and association with respiratory symptoms in the first year of life in 20 unselected infants. HRV was detected in 32% of 825 weekly nasal swabs. Seventy-four different types of all three species were identified. HRV presence and related respiratory symptoms are highly heterogeneous.

The SCITEAS experiment: Optical characterizations of sublimating icy planetary analogues

We have designed and built a laboratory facility to investigate the spectro-photometric and morphologic properties of different types of ice-bearing planetary surface analogs and follow their evolution upon exposure to a low pressure and low temperature environment. The results obtained with this experiment are used to verify and improve our interpretations of current optical remote-sensing datasets. They also provide valuable information for the development and operation of future optical instruments. The Simulation Chamber for Imaging the Temporal Evolution of Analogue Samples (SCITEAS) is a small thermal vacuum chamber equipped with a variety of ports and feedthroughs that permit both in-situ and remote characterizations as well as interacting with the sample. A large quartz window located directly above the sample is used to observe its surface from outside with a set of visible and near-infrared cameras. The sample holder can be easily and quickly inserted and removed from the chamber and is compatible with the other measurement facilities of the Laboratory for Outflow Studies of Sublimating Materials (LOSSy) at the University of Bern. We report here on the results of two of the first experiments performed in the SCITEAS chamber. In the first experiment, fine-grained water ice mixed with dark organic and mineral matter was left to sublime in vacuum and at low temperature, simulating the evolution of the surface of a comet nucleus approaching the Sun. We observed and characterized the formation and evolution of a crust of refractory organic and mineral matter at the surface of the sample and linked the evolution of its structure and texture to its spectro-photometric properties. In the second experiment, a frozen soil was prepared by freezing a mixture of smectite mineral and water. The sample was then left to sublime for 6 h to simulate the loss of volatiles from icy soil at high latitudes on Mars. Colour images were produced using the definitions of the filters foreseen for the CaSSIS imager of the Exomars/TGO mission in order to prepare future science operations.

The Marginal Impact of ENGOs in Different Types of Democratic Systems

Conventional wisdom suggests that environmental non-governmental organizations (ENGOs) play a major role in pushing states towards more ambitious environmental policies. However, demonstrating that this presumption is in fact true is rather difficult, because the same system structures of democracies that may create more opportunities for ENGO activities are also, on their own, conducive to better environmental policies. This leaves open the possibility that the additional (marginal) impact of ENGOs on policy making is smaller than presumed. In trying to disentangle these effects, this paper examines the influence of ENGOs contingent on key structural characteristics of democratic systems. We develop the argument that presidential systems with a plurality electoral rule per se tend to provide more environmental public goods, which induces a smaller marginal impact of ENGOs. Conversely, parliamentary systems with a proportional representation electoral rule are likely to provide fewer environmental public goods, which allows for a larger marginal impact of ENGOs. We find robust empirical support for these hypotheses in analyses that focus on the ratification behavior of 75 democracies vis-à-vis 250 international environmental agreements in 1973–2002.

The mechanism of the pharmacological actions of dexrazoxane on different tissue types

Approximately 6,600 people die from acute myelogenous leukemia (AML) on an annual basis. During the past 10 to 15 years, there has been gradual overall improvements in the therapy of this disease, yet the majority of patients with AML succumb to this disease. In an attempt to improve current therapeutic strategies for AML, we became interested in a commercially available drug, dexrazoxane, which protects against anthracycline-induced cardiotoxicity. We have investigated dexrazoxane's (DEX) effects on different tissue types in an effort to determine its unique mechanism of action. Colony forming assays were used to evaluate stem-cell renewal of myeloid cells in vitro and median effect analysis was used to evaluate antagonism, synergism, or additivity. The anthracyclines, doxorubicin, daunorubicin, and idarubicin were individually combined with DEX in leukemic myeloid models to determine if the combination of the two drugs resulted in a synergistic, additive or antagonistic effect. Etoposide and cytosine arabinoside were also evaluated in combination with DEX using the same in vitro model and evaluated similarly. ^ Dexrazoxane in combination with any of the anthracyclines was schedule dependent. The combination of DEX and anthracycline resulted in a greater antitumor effect than anthracycline alone except for DEX administered 24 hours before doxorubicin or daunorubicin. These data were corroborated through median effect analysis. Etoposide in combination with dexrazoxane was synergistic for all combinations, and the combination of cytosine arabinoside and DEX was schedule dependent. In contrast, using an in vivo gastrointestinal model, DEX in combination with doxorubicin was antagonistic for almost all of the ratios used, except for the highest. A Withers' assay was used to evaluate toxicity on jejunal crypt cells. No effect was apparent for the combination of idarubicin and DEX, however, as seen with RZ, DEX in addition to radiation greatly potentiated the cytotoxic effects of radiation on crypts. These paradoxical effects of dexrazoxane were initially enigmatic, but after additional investigation, we propose a model that explains our findings. We conclude that DEX in combination with anthracyclines produces an additive to synergistic antileukemic response and may have therapeutic potential clinically. Additionally, DEX protects the gastrointestinal tract from doxorubicin toxicity, which could have clinical implications for the administration of greater doses of doxorubicin. ^

Minority preferences and disease types for non-emergent emergency department usage in a CHIP population

Background. Of the over five million annual pediatric visits to U.S. emergency departments, one-third to one-half are for non-emergent conditions. Minorities are more likely to utilize the emergency department (ED) for non-emergent conditions. Very little research has analyzed the role of illness type, perceived need, or family preferences in explaining this disparity. ^ Objectives. This study examined racial-ethnic differences in preferences for care among non-emergent users of the ED. ^ Research design. A random selection of pediatric non-emergent ED users within a single CHIP managed care plan were surveyed regarding attitudes and health care preferences. Preferences for ED utilization were analyzed by racial-ethnic category, controlling for illness type, child and guardian age, education level, language, and perceived need. ^ Results. A total of 250 families were surveyed. Most respondents reported having a regular doctor, satisfaction with their physician, and ready access to their physician. Fifteen percent of White, 39% of Hispanic, and 38% of Black families reported they preferred the emergency department for ill care. In multivariate analysis, Whites families were significantly less likely to prefer the emergency department for ill visits (odds ratio, 0.12; 95% confidence interval 0.03-0.55) compared to Blacks and Hispanics. ^ Conclusions. Racial-ethnic disparities in non-emergent ED utilization may be partially explained by different preferences for care. ^ Key words: children, emergency department, preferences for care, disparities ^

Association between severity of Clostridium difficile disease and different types of toxins---A systematic review

Clostridium difficile is the most important and common cause of hospital-acquired diarrhea. Toxin A and B are two important protein toxins responsible for C. difficile disease. This systematic review was undertaken to summarize the association between severity of C. difficile disease and different types of toxins. Only 5 studies were found that met the inclusion criteria. Only two studies reported results that were statistically significant and that the C. difficile disease was more severe in patient with binary toxin genes. Other three studies did not report significant findings but the authors stated that these studies were too small to detect true association. The main difference between the studies which detect association and those which did not detect association was the sample size. Well-designed and large scale studies are needed to strengthen the relationship between severe disease and toxin types. ^