Experimental Investigation of the Effects of Relative Physical Orientation between Evaporator and Condenser for a Loop Heat Pipe

This research examined the effects on performance of varying angular orientation and height differences between evaporator and condenser for a loop heat pipe. Performance was defined as the difference in temperature between evaporator and condenser (DELTA T). The pipe was evaluated at varying input power (Qin) for: varying evaporator and condenser angles, different coolant temperatures, and varying relative height differences. All analysis included only steady state operation. The performance was influenced by condenser angles, with an optimal condenser angle for best performance being +45 degrees from horizontal. Additionally, the evaporator angles were found to influence performance only at low Qin and low coolant temperatures. For high Qin\u27 performance was independent of evaporator angle. For small Qin the DELTA T increased (poorer performance) with decreasing coolant temperature. However, for high Qin the DELTA T was independent of coolant temperature. For small Qin the DELTA T increased with increasing heights of evaporator over condenser. However, for high Qin the DELTA T was independent of the height difference. Additionally, pipe operation was sensitive to the rate of decrease of Qin. Finally, an unexplained anomaly shows the pipe to operate at two different DELTA T values for a given heat input

Controlled Ecological Life Support Systems: Natural and Artificial Ecosystems

The scientists supported by the NASA sponsored Controlled Ecological Life Support Systems (CELSS) program have played a major role in creating a Committee on Space Research (COSPAR) section devoted to the development of bioregenerative life support for use in space. The series of 22 papers were sponsored by Subcommission F.4. The papers deal with many of the diverse aspects of life support, and with outgrowth technologies that may have commercial applications in fields such as biotechnology and bioengineering. Papers from researchers in France, Canada, Japan and the USSR are also presented

CARDIAC AND OPERANT BEHAVIOR RESPONSE OF STARLINGS (Sturnus vulgaris) TO DISTRESS AND ALARM SOUNDS

A variety of auditory stimuli have been used for many years as a means of repelling nuisance birds from problem areas (Boudreau, 1968; Bremond et al., 1968; Frings and Jumber, 1954; Langowski et al., 1969; Nelson and Seubert 1966; Pearson and Corner, 1967; Thompson et al., 1966, 1968a, b). This approach to alleviating bird problems is ap- pealing because wild birds are considered very sensitive to sound stimuli of biological origin, and such stimuli are harmless to both target and nontarget species. The harmless aspect is an important advantage in dealing with wildlife related problems because of the increased public concern about the safety and environmental impact of the use of chemicals to alleviate some types of problems. The major limitation to the use of auditory stimuli to effectively repel birds is that, regardless of the strength of the communication signal, there is a decrement in physiological and behavioral response with repeated stimulation, resulting in habitua- tion and loss of repellent ability. In addition, the effectiveness of sound stimuli is in- fluenced by environmental and behavioral facts such as light intensity and flock behavior (Thompson et al., 1966, 1968a). Because of these limiting factors there is a need to compare the fright producing ability of different auditory stimuli to identify the strongest stimuli for field application. To facilitate this, we developed laboratory methodology to compare repellency strength of prerecorded sound stimuli. The methodology is illustrated in the present starling study by measuring (1) heart rate (HR) as a second order function of telemetered electrocar- diogram (ECG), and (2) keypecking rate (KPR) as an operant response in a switchback experimental design for four treatments. The switchback design was used to minimize error due to between-bird-variation in slope of the habituation curve and also to reduce the number of birds required for sensitive comparisons of stimuli

CARDIAC AND OPERANT BEHAVIOR RESPONSE OF STARLINGS (Sturnus vulgaris) TO DISTRESS AND ALARM SOUNDS

A variety of auditory stimuli have been used for many years as a means of repelling nuisance birds from problem areas (Boudreau, 1968; Bremond et al., 1968; Frings and Jumber, 1954; Langowski et al., 1969; Nelson and Seubert 1966; Pearson and Corner, 1967; Thompson et al., 1966, 1968a, b). This approach to alleviating bird problems is ap- pealing because wild birds are considered very sensitive to sound stimuli of biological origin, and such stimuli are harmless to both target and nontarget species. The harmless aspect is an important advantage in dealing with wildlife related problems because of the increased public concern about the safety and environmental impact of the use of chemicals to alleviate some types of problems. The major limitation to the use of auditory stimuli to effectively repel birds is that, regardless of the strength of the communication signal, there is a decrement in physiological and behavioral response with repeated stimulation, resulting in habitua- tion and loss of repellent ability. In addition, the effectiveness of sound stimuli is in- fluenced by environmental and behavioral facts such as light intensity and flock behavior (Thompson et al., 1966, 1968a). Because of these limiting factors there is a need to compare the fright producing ability of different auditory stimuli to identify the strongest stimuli for field application. To facilitate this, we developed laboratory methodology to compare repellency strength of prerecorded sound stimuli. The methodology is illustrated in the present starling study by measuring (1) heart rate (HR) as a second order function of telemetered electrocar- diogram (ECG), and (2) keypecking rate (KPR) as an operant response in a switchback experimental design for four treatments. The switchback design was used to minimize error due to between-bird-variation in slope of the habituation curve and also to reduce the number of birds required for sensitive comparisons of stimuli

Evaluation of Food Access and Food Security Concerns Among Public Health Housing Residents

Background: In 2012, food insecurity affected 14.5% of the households in the U.S and 20% in the state of Georgia. Individuals who are food-insecure can experience malnutrition, and social and physical problems. The purpose of this study was to assess food access and security concerns in two counties of the North Central Health District 5-2 (NCHD 5-2) in Georgia and to aid in devising interventions to increase food access and reduce food insecurity. Methods: Data collection involved surveying 399 public housing residents within two NCHD 5-2 counties using the Household Food Security Survey developed by the US Department of Agriculture. The survey contained 24 questions focusing on demographics and household food status and on the severity and prevalence of food access and security. Results: Of the 399 participants, 91.9% reported annual household incomes less than $30,000; 61% (n = 244) reported receiving Supplemental Nutrition Assistance Program (SNAP/food stamps) benefits, 11% (n = 46) received Women, Infants, and Children (WIC) benefits, and 3.3% (n = 13) received Temporary Assistance for Needy Families (TANF). Results for food security status (whether or not families have access to food at all times) showed that 7.3% (n = 29) were classified as high food secure, 22.8% (n = 91) as marginally food secure, 30.6% (n = 122) as low food secure, and 39.3% (n = 157) as very low food secure. Conclusions: Most of the residents with some form of food insecurity received government food assistance, yet still identified as being unable to feed themselves or their families for the month. Recommendations to evaluate this problem include additional research and implementation of public health efforts to address food access and insecurity through policy changes and implementation of programs

Pathway interactions between MAPKs, mTOR, PKA, and the glucocorticoid receptor in lymphoid cells

BACKGROUND: Glucocorticoids are frequently used as a primary chemotherapeutic agent in many types of human lymphoid malignancies because they induce apoptosis through activation of the glucocorticoid receptor, with subsequent alteration of a complex network of cellular mechanisms. Despite clinical usage for over fifty years, the complete mechanism responsible for glucocorticoid-related apoptosis or resistance remains elusive. The mitogen-activated protein kinase pathway is a signal transduction network that influences a variety of cellular responses through phosphorylation of specific target substrates, including the glucocorticoid receptor. In this study we have evaluated the pharmaceutical scenarios which converge on the mitogen-activated protein kinase pathway to alter glucocorticoid sensitivity in clones of human acute lymphoblastic CEM cells sensitive and refractory to apoptosis in response to the synthetic glucocorticoid dexamethasone. RESULTS: The glucocorticoid-resistant clone CEM-C1-15 displays a combination of high constitutive JNK activity and dexamethasone-induced ERK activity with a weak induction of p38 upon glucocorticoid treatment. The cells become sensitive to glucocorticoid-evoked apoptosis after: (1) inhibition of JNK and ERK activity, (2) stimulation of the cAMP/PKA pathway with forskolin, or (3) inhibition of mTOR with rapamycin. Treatments 1–3 in combination with dexamethasone alter the intracellular balance of phospho-MAPKs by lowering JNK phosphorylation and increasing the level of glucocorticoid receptor phosphorylated at serine 211, a modification known to enhance receptor activity. CONCLUSION: Our data support the hypothesis that mitogen-activated protein kinases influence the ability of certain malignant lymphoid cells to undergo apoptosis when treated with glucocorticoid. Activated/phosphorylated JNK and ERK appear to counteract corticoid-dependent apoptosis. Inhibiting these MAPKs restores corticoid sensitivity to a resistant clone of CEM cells. Forskolin, which activates the cAMP pathway, and rapamycin, which inhibits mTOR, also inhibit JNK. Further, the sensitizing treatments result in a largely dexamethasone-dependent increase in the total pool of glucocorticoid receptor phosphorylated at serine 211. The phospho-serine 211 receptor is known to be more potent in activating gene transcription and apoptosis. The interactive effects demonstrated here in reverting resistant cells to corticoid sensitivity could provide therapeutic clinical potential in the treatment of lymphoid malignancies

Gene expression profiling of leukemic cells and primary thymocytes predicts a signature for apoptotic sensitivity to glucocorticoids

<p>Abstract</p> <p>Background</p> <p>Glucocorticoids (GC's) play an integral role in treatment strategies designed to combat various forms of hematological malignancies. GCs also are powerful inhibitors of the immune system, through regulation of appropriate cytokines and by causing apoptosis of immature thymocytes. By activating the glucocorticoid receptor (GR), GCs evoke apoptosis through transcriptional regulation of a complex, interactive gene network over a period of time preceding activation of the apoptotic enzymes. In this study we used microarray technology to determine whether several disparate types of hematologic cells, all sensitive to GC-evoked apoptosis, would identify a common set of regulated genes. We compared gene expression signatures after treatment with two potent synthetic GCs, dexamethasone (Dex) and cortivazol (CVZ) using a panel of hematologic cells. Pediatric CD4+/CD8+ T-cell leukemia was represented by 3 CEM clones: two sensitive, CEM-C7–14 and CEM-C1–6, and one resistant, CEM-C1–15, to Dex. CEM-C1–15 was also tested when rendered GC-sensitive by several treatments. GC-sensitive pediatric B-cell leukemia was represented by the SUP-B15 line and adult B-cell leukemia by RS4;11 cells. Kasumi-1 cells gave an example of the rare Dex-sensitive acute myeloblastic leukemia (AML). To test the generality of the correlations in malignant cell gene sets, we compared with GC effects on mouse non-transformed thymocytes.</p> <p>Results</p> <p>We identified a set of genes regulated by GCs in all GC-sensitive malignant cells. A portion of these were also regulated in the thymocytes. Because we knew that the highly Dex-resistant CEM-C1–15 cells could be killed by CVZ, we tested these cells with the latter steroid and again found that many of the same genes were now regulated as in the inherently GC-sensitive cells. The same result was obtained when we converted the Dex-resistant clone to Dex-sensitive by treatment with forskolin (FSK), to activate the adenyl cyclase/protein kinase A pathway (PKA).</p> <p>Conclusion</p> <p>Our results have identified small sets of genes that correlate with GC-sensitivity in cells from several hematologic malignancies. Some of these are also regulated in normal mouse thymocytes.</p

A Six-Planet System Around the Star HD 34445

We present a new precision radial velocity dataset that reveals a multi-planet system orbiting the G0V star HD 34445. Our 18-year span consists of 333 precision radial velocity observations, 56 of which were previously published, and 277 which are new data from Keck Observatory, Magellan at Las Campanas Observatory, and the Automated Planet Finder at Lick Observatory. These data indicate the presence of six planet candidates in Keplerian motion about the host star with periods of 1057, 215, 118, 49, 677, and 5700 days, and minimum masses of 0.63, 0.17, 0.1, 0.05, 0.12 and 0.38 Jupiter masses respectively. The HD 34445 planetary system, with its high degree of multiplicity, its long orbital periods, and its induced stellar radial velocity half-amplitudes in the range $2 \,{\rm m\, s^{-1}} \lesssim K \lesssim 5\,{\rm m\, s^{-1}}$ is fundamentally unlike either our own solar system (in which only Jupiter and Saturn induce significant reflex velocities for the Sun), or the Kepler multiple-transiting systems (which tend to have much more compact orbital configurations)Comment: 10 pages, 11 figure