Measurements of production in fertilized salt-water

The present paper describes some results of several exploratory experiments made at the Woods Hole Oceanographic Institution in connection with a proposed study of organic production in salt waters. An attempt is made to relate the viewpoint of the present paper to the more outstanding aims of fertilization work. Aside from practical matters of aquiculture, addition of nutrients to water is a valuable tool for studying what has been called food-chain dynamics. Briefly stated, the object of the described experiments was to determine immediate effects of fertilization upon the vital activities of the phytoplankton

Is superiority a necessary aspect of cruelty?

Chapman & Huffman argue that humans inflict cruelty without apparent concern because of their categorization of the victims as inferior. The supposed inferiority of non-human animals can be argued against on the basis of documentation and analysis of behaviour. Humans continue to inflict cruelty on their own and other species. It is not obvious that a sense of superiority is a necessary aspect of cruel behaviour. Nor is it obvious that further enlightenment regarding the cognitive status of non-humans will diminish cruelty

On the Elevated Temperature Thermal Stability of Nanoscale Mn-Ni-Si Precipitates Formed at Lower Temperature in Highly Irradiated Reactor Pressure Vessel Steels.

Atom probe tomography (APT) and scanning transmission electron microscopy (STEM) techniques were used to probe the long-time thermal stability of nm-scale Mn-Ni-Si precipitates (MNSPs) formed in intermediate and high Ni reactor pressure vessel steels under high fluence neutron irradiation at ≈320 °C. Post irradiation annealing (PIA) at 425 °C for up to 57 weeks was used to determine if the MNSPs are: (a) non-equilibrium solute clusters formed and sustained by radiation induced segregation (RIS); or, (b) equilibrium G or Γ2 phases, that precipitate at accelerated rates due to radiation enhanced diffusion (RED). Note the latter is consistent with both thermodynamic models and x-ray diffraction (XRD) measurements. Both the experimental and an independently calibrated cluster dynamics (CD) model results show that the stability of the MNSPs is very sensitive to the alloy Ni and, to a lesser extent, Mn content. Thus, a small fraction of the largest MNSPs in the high Ni steel persist, and begin to coarsen at long times. These results suggest that the MNSPs remain a stable phase, even at 105 °C higher than they formed at, thus are most certainly equilibrium phases at much lower service relevant temperatures of ≈290 °C

Trauma and PTSD symptoms: Does spiritual struggle mediate the link?

Because exposure to potentially traumatic events is common (Kessler, Sonnega, Bromet, & Hughes, 1995), the mechanisms through which posttraumatic stress disorder (PTSD) symptoms develop is a critical area of investigation (Ozer, Best, Lipsey, & Weiss, 2003). Among the mechanisms that may predict PTSD symptoms is spiritual struggle, a set of negative religious cognitions related to understanding or responding to stressful events. Although prominent theories emphasize cognitive factors in the development and maintenance of PTSD symptoms, they have not explicitly addressed spiritual struggle. The present prospective study tested the role of spiritual struggle in the development and maintenance of PTSD symptoms following trauma. We assessed exposure to trauma and nontrauma events during the first year of college, spiritual struggle due to the most stressful event, and PTSD symptoms resulting from the index event. Spiritual struggle partially mediated the relationship between trauma and PTSD symptoms. We found interesting that some individual subscales of spiritual struggle (specifically, Punishing God Reappraisal, Reappraisal of God's Powers, and Spiritual Discontent) partially mediated the relationship between trauma and PTSD symptoms; however, reappraisal of the event to evil forces did not relate to PTSD symptoms. These results suggest that spiritual struggle is an important cognitive mechanism for many trauma victims and may have relevance for cognitive therapy for PTSD

Health Care Delivery Practices in Huntington's Disease Specialty Clinics : An International Survey

The CHDI Foundation, Inc. funds Enroll-HD and the activities of the Enroll-HD Care Improvement Committee, including the present survey. We would like to acknowledge the Enroll-HD and REGISTRY administrative staff that assisted in the recruitment of sites and sites that completed the survey.Peer reviewedPublisher PD

Fingerprints of biocomplexity: Taxon‐specific growth of phytoplankton in relation to environmental factors

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110012/1/lno2004494part21446.pd

Cladoceran birth and death rates estimates

I. Birth and death rates of natural cladoceran populations cannot be measured directly. Estimates of these population parameters must be calculated using methods that make assumptions about the form of population growth. These methods generally assume that the population has a stable age distribution. 2. To assess the effect of variable age distributions, we tested six egg ratio methods for estimating birth and death rates with data from thirty-seven laboratory populations of Daphnia pulicaria. The populations were grown under constant conditions, but the initial age distributions and egg ratios of the populations varied. Actual death rates were virtually zero, so the difference between the estimated and actual death rates measured the error in both birth and death rate estimates. 3. The results demonstrate that unstable population structures may produce large errors in the birth and death rates estimated by any of these methods. Among the methods tested, Taylor and Slatkin's formula and Paloheimo's formula were most reliable for the experimental data. 4. Further analyses of three of the methods were made using computer simulations of growth of age-structured populations with initially unstable age distributions. These analyses show that the time interval between sampling strongly influences the reliability of birth and death rate estimates. At a sampling interval of 2.5 days (equal to the duration of the egg stage), Paloheimo's formula was most accurate. At longer intervals (7.5–10 days), Taylor and Slatkin's formula which includes information on population structure was most accurate

Dimensional structure and correlates of posttraumatic stress symptoms following suspected acute coronary syndrome

Background Posttraumatic stress disorder (PTSD) is a heterogeneous construct, and some have suggested that PTSD triggered by acute coronary syndrome (ACS) may differ from PTSD due to prototypical traumas. Methods We conducted the first examination of the latent structure of PTSD symptoms after suspected ACS in 399 adults in the REactions to Acute Care and Hospitalization (REACH) study, an observational cohort study of patients recruited from the emergency department during evaluation for ACS. Using confirmatory factor analysis, we compared the 4-factor dysphoria, 4-factor numbing, and 5-factor dysphoric arousal models of PTSD. Results Although all models fit well, the dysphoria model was selected as the best-fitting model. Further, there was measurement invariance of the dysphoria model by sex. PTSD dimensions evidenced differential associations with indicators of threat perception during ACS evaluation and adherence to cardioprotective medication. Limitations One limitation of this investigation is the use of self-report measures. In addition, only one-third of the sample was diagnosed with ACS at discharge; the remaining participants received diagnoses such as chest pain without a cardiac diagnosis, another symptom/disease process (e.g., hypertensive chronic kidney disease), or another cardiac disease. Conclusions Findings suggest that suspected ACS-related PTSD symptoms are best-represented by a 4-factor structure distinguishing between specific (e.g., re-experiencing) and non-specific (dysphoria) symptoms of PTSD that has received support in the broader PTSD literature