Heat transfer with very high free stream turbulence

Stanton numbers as much as 350 percent above the accepted correlations for flat plate turbulent boundary layer heat transfer have been found in experiments on a low velocity air flow with very high turbulence (up to 50 percent). These effects are far larger that have been previously reported and the data do not correlate as well in boundary layer coordinates (Stanton number and Reynolds number) as they do in simpler coordinates: h vs. X. The very high relative turbulence levels were achieved by placing the test plate in different positions in the margin of a large diameter free jet. The large increases may be due to organized structures of large scale which are present in the marginal flowfield around a free jet

Heat transfer with very high free-stream turbulence and streamwise vortices

Results are presented for two experimental programs related to augmentation of heat transfer by complex flow characteristics. In one program, high free stream turbulence (up to 63 percent) was shown to increase the Stanton number by more than a factor of 5, compared with the normally expected value based on x-Reynolds number. These experiments are being conducted in a free-jet facility, near the margins of the jet. To a limited extent, the mean velocity, turbulence intensity, and integral length scale can be separately varied. The results show that scale is a very important factor in determining the augmentation. Detailed studies of the turbulence structure are being carried out using an orthogonal triple hot-wire anemometer equipped with a fourth wire for measuring temperature. The v' component of turbulence appears to be distributed differently from u' or w'. In the second program, the velocity distributions and boundary layer thicknesses associated with a pair of counter-rotating, streamwise vortices were measured. There is a region of considerably thinned boundary layer between the two vortices when they are of approximately the same strength. If one vortex is much stronger than the other, the weaker vortex may be lifted off the surface and absorbed into the stronger

"Prolonged grief disorder" and "persistent complex bereavement disorder", but not "complicated grief", are one and the same diagnostic entity: an analysis of data from the Yale Bereavement Study

There exists a general consensus that prolonged grief disorder (PGD), or some variant of PGD, represents a distinct mental disorder worthy of diagnosis and treatment. Nevertheless, confusion remains over whether different names and proposed symptom criteria for this disorder identify the same or different diagnostic entities. This study aimed to determine whether PGD, complicated grief (CG), and persistent complex bereavement disorder (PCBD) as described by the DSM-5 are substantively or merely semantically different diagnostic entities. Data were derived from the Yale Bereavement Study, a longitudinal community-based study of bereaved individuals funded by the US National Institute of Mental Health, designed explicitly to evaluate diagnostic criteria for disordered grief. The results suggested that the difference between PGD and PCBD is only semantic. The level of agreement between the original PGD test, a new version of the PGD test proposed for ICD-11 and the PCBD test was high (pairwise kappa coefficients = 0.80-0.84). Their estimates of rate of disorder in this community sample were similarly low (∼10%). Their levels of diagnostic specificity were comparably high (95.0-98.3%). Their predictive validity was comparable. In contrast, the test for CG had only moderate agreement with those for PGD and PCBD; its estimate of rate of disorder was three-fold higher (∼30%); its diagnostic specificity was poorer, and it had no predictive validity. We conclude that PGD, PCBD and proposed ICD-11, but not CG, symptom-diagnostic tests identify a single diagnostic entity. Ultimately, brief symptom-diagnostic tests, such as the one proposed here for ICD-11, may have the greatest clinical utility

Mutual Potential of Homogeneous Polyhedra

The mutual gravitational potential between a pair of homogeneous polyhedra is expressed using an infinite series. The nested volume integrals are evaluated analytically and result in simple tensor expressions containing no special functions. However, complexity increases as O (6 n ), where n is the term degree. An alternate formulation due to Liebenthal is also presented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42570/1/10569_2004_Article_4621.pd

Estimation of interdomain flexibility of N-terminus of factor H using residual dipolar couplings

Characterization of segmental flexibility is needed to understand the biological mechanisms of the very large category of functionally diverse proteins, exemplified by the regulators of complement activation, that consist of numerous compact modules or domains linked by short, potentially flexible, sequences of amino acid residues. The use of NMR-derived residual dipolar couplings (RDCs), in magnetically aligned media, to evaluate interdomain motion is established but only for two-domain proteins. We focused on the three N-terminal domains (called CCPs or SCRs) of the important complement regulator, human factor H (i.e. FH1-3). These domains cooperate to facilitate cleavage of the key complement activation-specific protein fragment, C3b, forming iC3b that no longer participates in the complement cascade. We refined a three-dimensional solution structure of recombinant FH1-3 based on nuclear Overhauser effects and RDCs. We then employed a rudimentary series of RDC datasets, collected in media containing magnetically aligned bicelles (disk-like particles formed from phospholipids) under three different conditions, to estimate interdomain motions. This circumvents a requirement of previous approaches for technically difficult collection of five independent RDC datasets. More than 80% of conformers of this predominantly extended three-domain molecule exhibit flexions of < 40 °. Such segmental flexibility (together with the local dynamics of the hypervariable loop within domain 3), could facilitate recognition of C3b via initial anchoring and eventual reorganization of modules to the conformation captured in the previously solved crystal structure of a C3b:FH1-4 complex

The Role of Advance Care Planning in Cancer Patient and Caregiver Grief Resolution: Helpful or Harmful?

Cancer patients and their family caregivers experience various losses when patients become terminally ill, yet little is known about the grief experienced by patients and caregivers and factors that influence grief as patients approach death. Additionally, few, if any, studies have explored associations between advance care planning (ACP) and grief resolution among cancer patients and caregivers. To fill this knowledge gap, the current study examined changes in grief over time in patients and their family caregivers and whether changes in patient grief are associated with changes in caregiver grief. We also sought to determine how grief changed following the completion of advance directives. The sample included advanced cancer patients and caregivers (n = 98 dyads) from Coping with Cancer III, a federally funded, multi-site prospective longitudinal study of end-stage cancer care. Participants were interviewed at baseline and at follow-up roughly 2 months later. Results suggest synchrony, whereby changes in patient grief were associated with changes in caregiver grief. We also found that patients who completed a living will (LW) experienced increases in grief, while caregivers of patients who completed a do-not-resuscitate (DNR) order experienced reductions in grief, suggesting that ACP may prompt “grief work” in patients while promoting grief resolution in caregivers