Dissolved organic matter quantity and quality response of tropical rainforest headwater rivers to the transition from dry to wet season

Dissolved organic matter (DOM) and its composition in aquatic ecosystems is a key indicator of ecosystem function and an important component of the global carbon cycle. Tropical rainforest headwaters play an important role in global carbon cycling. However, there is a large uncertainty on how DOM sources interact during mobilisation and the potential fate of associated carbon and nutrients. Using field techniques to measure dissolved organic carbon (DOC) concentration and composition, changes in DOM source from headwaters to larger downstream rivers were observed. This study shows that the hydrological connectivity, developed during the transition from dry to wet seasons, changes the DOM supply and transport across a tropical river catchment. The observed variability in the DOC-river discharge relationship provides further evidence of the changes in the DOM supply in a small headwater. This novel insight into the seasonal changes of the dynamics of DOM supply to the river helps understanding the mobilization of terrestrial DOM to tropical headwaters and its export from smaller to larger rivers. It also highlights the data gap in the study of smaller headwaters which may account for uncertainty in estimating the terrestrial carbon transported by inland waters.

The Close-Up Imager Onboard the ESA ExoMars Rover: Objectives, Description, Operations, and Science Validation Activities

The Close-Up Imager (CLUPI) onboard the ESA ExoMars Rover is a powerful high-resolution color camera specifically designed for close-up observations. Its accommodation on the movable drill allows multiple positioning. The science objectives of the instrument are geological characterization of rocks in terms of texture, structure, and color and the search for potential morphological biosignatures. We present the CLUPI science objectives, performance, and technical description, followed by a description of the instrument's planned operations strategy during the mission on Mars. CLUPI will contribute to the rover mission by surveying the geological environment, acquiring close-up images of outcrops, observing the drilling area, inspecting the top portion of the drill borehole (and deposited fines), monitoring drilling operations, and imaging samples collected by the drill. A status of the current development and planned science validation activities is also given. Key Words: Mars-Biosignatures-Planetary Instrumentation. Astrobiology 17, 595-611.

El'gygytgyn impact crater, Chukotka, Arctic Russia: Impact cratering aspects of the 2009 ICDP drilling project

The El'gygytgyn impact structure in Chukutka, Arctic Russia, is the only impact crater currently known on Earth that was formed in mostly acid volcanic rocks (mainly of rhyolitic, with some andesitic and dacitic, compositions). In addition, because of its depth, it has provided an excellent sediment trap that records paleoclimatic information for the 3.6 Myr since its formation. For these two main reasons, because of the importance for impact and paleoclimate research, El'gygytgyn was the subject of an International Continental Scientific Drilling Program (ICDP) drilling project in 2009. During this project, which, due to its logistical and financial challenges, took almost a decade to come to fruition, a total of 642.3 m of drill core was recovered at two sites, from four holes. The obtained material included sedimentary and impactite rocks. In terms of impactites, which were recovered from 316.08 to 517.30 m depth below lake bottom (mblb), three main parts of that core segment were identified: from 316 to 390 mblb polymict lithic impact breccia, mostly suevite, with volcanic and impact melt clasts that locally contain shocked minerals, in a fine-grained clastic matrix; from 385 to 423 mblb, a brecciated sequence of volcanic rocks including both felsic and mafic (basalt) members; and from 423 to 517 mblb, a greenish rhyodacitic ignimbrite (mostly monomict breccia). The uppermost impactite (316-328 mblb) contains lacustrine sediment mixed with impact-affected components. Over the whole length of the impactite core, the abundance of shock features decreases rapidly from the top to the bottom of the studied core section. The distinction between original volcanic melt fragments and those that formed later as the result of the impact event posed major problems in the study of these rocks. The sequence that contains fairly unambiguous evidence of impact melt (which is not very abundant anyway, usually less than a few volume%) is only about 75 m thick. The reason for this rather thin fallback impactite sequence may be the location of the drill core on an elevated part of the central uplift. A general lack of large coherent melt bodies is evident, similar to that found at the similarly sized Bosumtwi impact crater in Ghana that, however, was formed in a target composed of a thin layer of sediment above crystalline rocks.

A study of the role of the generalist oncology nurse as a basis for revision of the blueprint for certification

PURPOSE/OBJECTIVES

To delineate the current role of the generalist oncology nurse as a basis for revision of the blueprint for the OCN Exam.

DESIGN

Survey of generalist oncology nurses.

SAMPLE

1,200 oncology nurses randomly chosen from the general membership of the Oncology Nursing Society who completed and returned surveys.

METHODS

Surveys developed by subject matter experts and mailed by American College Testing.

MAIN RESEARCH VARIABLES

Frequency and importance of 201 oncology nursing activities previously identified by a group of experts in oncology nursing.

FINDINGS

Highest ranked items for combined frequency and importance pertained to comfort, information, protective mechanisms, and coping. Lowest ranked items pertained to prevention, detection, research, and sexuality.

CONCLUSIONS

The blueprint was redesigned to include eight domains of practice: quality of life (27%), gastrointestinal and urinary function (15%), protective mechanisms (15%), scientific basis for practice (12%), cardiopulmonary function (10%), health promotion (8%), oncologic emergencies (7%), and professional performance (6%).

IMPLICATIONS FOR NURSING PRACTICE

Because oncology nursing is changing, it is necessary to reconfirm and update the blueprint for the certification exam. Certification exams for the generalist nurse beginning in May 1996 were based on this updated blueprint.

Advanced practice in oncology nursing: a role delineation study

PURPOSE

To identify the elements that comprise the role of the advanced practice oncology nurse.

DESIGN

Survey.

SETTING

National.

SAMPLE

637 master's-prepared nurses in oncology clinical practice and 619 baccalaureate nurses who were in their first four years of certification as oncology nurses.

METHODS

Using a 190-item survey composed of five subscales (Direct Caregiver, Consultant, Administrator/Coordinator, Researcher, and Educator) listing advanced practice behaviors, respondents were asked to indicate the frequency with which they performed each behavior and the importance of each behavior to their practice.

MAIN RESEARCH VARIABLES

The elements of the advanced practice role differentiated from those elements of the role of the nurse who is practicing at the generalist level (i.e., non-master's-prepared).

FINDINGS

The majority of items showed a significant difference between the the two groups with the greatest similarities in the area of Direct Caregiver and the greatest differences in the areas of Consultant and Researcher. Advanced practice nurses indicated that they performed the behaviors on the Direct Caregiver and Educator subscales most frequently and believed these behaviors to be most important to their practice.

CONCLUSION

Significant differences exist between the roles of nurses in basic and advanced oncology nursing practice.

IMPLICATIONS FOR NURSING PRACTICE

The results of the role delineation study have been used to design the blueprint for the Advanced Oncology Nursing Certification Test, to be administered for the first time in April 1995.

Physical and social impact of alpha 1-antitrypsin deficiency: results of a survey

BACKGROUND

Emphysema associated with alpha 1-antitrypsin deficiency can impose serious impairment.

OBJECTIVE

To gather information about the impact of severe alpha 1-antitrypsin deficiency.

METHODS

Mail survey, descriptive statistics.

RESULTS

We sent a survey to 1730 subscribers to a national newsletter, 850 of whom had previously stated they had alpha 1-antitrypsin deficiency. A total of 414 questionnaires were returned; 398 respondents said they had alpha 1-antitrypsin deficiency, and 300 said they had the PiZZ phenotype. Sixty-six respondents who said they had the disease did not know their phenotype. Among the 304 respondents with severe deficiency, the mean age at the time symptoms first appeared was 35.0 years, but the mean age when the disease was diagnosed was 41.3 years. Overall, 75.3% of respondents with severe deficiency reported at least one adverse effect: 44.4% retired early, and 19.1% changed to a physically easier job. The duration of diagnostic delay correlated with the degree of adverse psychosocial effects.

CONCLUSIONS

Alpha 1-antitrypsin deficiency frequently escapes diagnosis despite many medical encounters. Affected individuals are often unaware of basic details of their disease. Many patients report adverse psychosocial effects. Delay in diagnosing this disease is associated with adverse psychosocial effects.

The effect of neuroleptics and tardive dyskinesia on smooth-pursuit eye movement in chronic schizophrenics

We sought to determine whether such state-related factors as neuroleptic treatment and facio-oral tardive dyskinesia (TD) influence smooth-pursuit eye movement (SPEM) in chronic schizophrenics. The design involved 100 schizophrenics, 64 of whom showed "abnormal" eye tracking. Experimentally drug-withdrawn patients, some of whom were clinically relapsed, were compared with control patients who continued taking medication in prewithdrawal and postwithdrawal SPEM tests. All groups showed a slight worsening in eye-tracking performance on two postwithdrawal tests, but significant group-by-test session "interactions" were not demonstrable. We also determined that patients with TD tend to substitute large, nontracking saccades for SPEM to a significantly greater extent than nondyskinetic patients. Our findings strengthen the supposition that impaired SPEM is a trait in many schizophrenics but suggest that patients with TD be excluded in future studies of SPEM addressed to trait issues.

Episodic and residual thought pathology in chronic schizophrenics: effect of neuroleptics

We sought to determine the effect of neuroleptic treatment on thought disorder in chronic schizophrenics, using the Thought Disorder Index (TDI). We were able to demonstrate that high levels of thought disorder are found in chronic schizophrenic and schizoaffective patients, while in both bipolar patients and normal controls thought pathology is minimal. Moreover, the TDI appears to be particularly well suited to the characterization of thought disorder in chronic schizophrenics. For total scores on the TDI, we were unable to demonstrate a significant reduction in thought pathology, although it was evident that thought disorder as reflected in the Conceptual Disorganization and Unusual Thought Content subscales of the Brief Psychiatric Rating Scale is significantly reduced by neuroleptics. In analyses of subscores of the TDI reflecting four levels of severity, we were able to show that more severe forms of thought pathology are normalized by neuroleptics, while less severe pathology is largely unaffected. Our results suggest that neuroleptic treatment reduces thought pathology associated with acute episodes, but that somewhat milder, though still disabling, residual thought pathology persists after clinical remission has been attained.