Sample records for freezing point depression

  1. Study of freezing-point depression of selected food extracts

    SciTech Connect

    Tanaka, Fumihiko [Kagoshima Univ. (Japan). Dept. of Agricultural Systems Engineering; Murata, Satoshi; Habara, Kazuhiro; Amaratunga, K.S.P. [Kyushu Univ., Fukuoka (Japan). Dept. of Agricultural Engineering

    1996-12-31

    The phenomenon of freezing-point depression that accompanies the solute concentration of selected food extracts was investigated to reveal the characteristics of solid-liquid phase equilibrium. The freezing curves of various food extracts did not exhibit ideal solution behavior in the higher concentration range. The experimental data were fitted to new freezing-point depression equations by the method of nonlinear least squares, and the results clearly indicated that the calculated freezing points at various concentrations were in good agreement with the experimental data. Furthermore, by using the determined parameters, the freezing ratio and the activation coefficient were derived.

  2. Ice slurry cooling research: Microscale study of ice particles characteristics, role of freezing point depressant, and influence on slurry fluidity

    Microsoft Academic Search

    K. Hayashi; K. Kasza

    2000-01-01

    The influences of freezing-point-depressants on ice slurry characteristics in the form of ice slurry fluidity and on the microscale ice particle features are studied. The results identify microscale features of ice particles such as surface roughness that greatly influence slurry fluidity that are altered favorably by the use of a freezing point depressant. The engineering of a workable and efficient

  3. Ice slurry cooling research: Microscale study of ice particles characteristics, role of freezing point depressant, and influence on slurry fluidity

    SciTech Connect

    Hayashi, K.; Kasza, K.

    2000-05-03

    The influences of freezing-point-depressants on ice slurry characteristics in the form of ice slurry fluidity and on the microscale ice particle features are studied. The results identify microscale features of ice particles such as surface roughness that greatly influence slurry fluidity that are altered favorably by the use of a freezing point depressant. The engineering of a workable and efficient ice slurry cooling system depends very strongly on the characteristics of the individual ice particles in the slurry and, in turn, on the method of ice production. Findings from this study provide guidance on the fluidity and handleability of slurry produced by several methods currently under development and already many achieved.

  4. Accuracy of two osmometers on standard samples: electrical impedance technique and freezing point depression technique

    NASA Astrophysics Data System (ADS)

    García-Resúa, Carlos; Pena-Verdeal, Hugo; Miñones, Mercedes; Gilino, Jorge; Giraldez, Maria J.; Yebra-Pimentel, Eva

    2013-11-01

    High tear fluid osmolarity is a feature common to all types of dry eye. This study was designed to establish the accuracy of two osmometers, a freezing point depression osmometer (Fiske 110) and an electrical impedance osmometer (TearLab™) by using standard samples. To assess the accuracy of the measurements provided by the two instruments we used 5 solutions of known osmolarity/osmolality; 50, 290 and 850 mOsm/kg and 292 and 338 mOsm/L. Fiske 110 is designed to be used in samples of 20 ?l, so measurements were made on 1:9, 1:4, 1:1 and 1:0 dilutions of the standards. Tear Lab is addressed to be used in tear film and only a sample of 0.05 ?l is required, so no dilutions were employed. Due to the smaller measurement range of the TearLab, the 50 and 850 mOsm/kg standards were not included. 20 measurements per standard sample were used and differences with the reference value was analysed by one sample t-test. Fiske 110 showed that osmolarity measurements differed statistically from standard values except those recorded for 290 mOsm/kg standard diluted 1:1 (p = 0.309), the 292 mOsm/L H2O sample (1:1) and 338 mOsm/L H2O standard (1:4). The more diluted the sample, the higher the error rate. For the TearLab measurements, one-sample t-test indicated that all determinations differed from the theoretical values (p = 0.001), though differences were always small. For undiluted solutions, Fiske 110 shows similar performance than TearLab. However, for the diluted standards, Fiske 110 worsens.

  5. 7.NS Comparing Freezing Points

    NSDL National Science Digital Library

    This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Ocean water freezes at about $-2 \\frac12 ^\\circ C$. Fresh water freezes at $0 ^\\circ C$. Antifreeze, a liquid used in the radiators of cars, freezes at...

  6. Freezing Point of Milk: A Natural Way to Understand Colligative Properties

    ERIC Educational Resources Information Center

    Novo, Mercedes; Reija, Belen; Al-Soufi, Wajih

    2007-01-01

    A laboratory experiment is presented in which the freezing point depression is analyzed using milk as solution. The nature of milk as a mixture of different solutes makes it a suitable probe to learn about colligative properties. The first part of the experiment illustrates the analytical use of freezing point measurements to control milk quality,…

  7. Device and method for determining freezing points

    NASA Technical Reports Server (NTRS)

    Mathiprakasam, Balakrishnan (Inventor)

    1986-01-01

    A freezing point method and device (10) are disclosed. The method and device pertain to an inflection point technique for determining the freezing points of mixtures. In both the method and device (10), the mixture is cooled to a point below its anticipated freezing point and then warmed at a substantially linear rate. During the warming process, the rate of increase of temperature of the mixture is monitored by, for example, thermocouple (28) with the thermocouple output signal being amplified and differentiated by a differentiator (42). The rate of increase of temperature data are analyzed and a peak rate of increase of temperature is identified. In the preferred device (10) a computer (22) is utilized to analyze the rate of increase of temperature data following the warming process. Once the maximum rate of increase of temperature is identified, the corresponding temperature of the mixture is located and earmarked as being substantially equal to the freezing point of the mixture. In a preferred device (10), the computer (22), in addition to collecting the temperature and rate of change of temperature data, controls a programmable power supply (14) to provide a predetermined amount of cooling and warming current to thermoelectric modules (56).

  8. Freezing and Decorated Poisson Point Processes

    NASA Astrophysics Data System (ADS)

    Subag, Eliran; Zeitouni, Ofer

    2015-07-01

    The limiting extremal processes of the branching Brownian motion (BBM), the two-speed BBM, and the branching random walk are known to be randomly shifted decorated Poisson point processes (SDPPP). In the proofs of those results, the Laplace functional of the limiting extremal process is shown to satisfy for any nonzero, nonnegative, compactly supported, continuous function f, where is the shift operator, is a real number that depends on f, and g is a real function that is independent of f. We show that, under some assumptions, this property characterizes the structure of SDPPP. Moreover, when it holds, we show that g has to be a convolution of the Gumbel distribution with some measure. The above property of the Laplace functional is closely related to a `freezing phenomenon' that is expected to occur in a wide class of log-correlated fields, and which has played an important role in the analysis of various models. Our results shed light on this intriguing phenomenon and provide a natural tool for proving an SDPPP structure in these and other models.

  9. THE URANIUM HEXAFLUORIDE-HYDROGEN FLUORIDE FREEZING POINT CURVE AND ITS APPLICATION TO A METHOD OF ANALYSIS

    Microsoft Academic Search

    R. J. Wertz; W. D. Hedge

    1960-01-01

    The freezing point curve for the system uranium hexafluoride--hydrogen ; fluoride was determined over the range 0.0 to 0.6 wt% hydrogen fluoride and is ; represented by the equation wt% HF = 0.0841 DELTA t + 0.1020 DELTA t² -- ; 0.1046 DELTA t³ + 0.0363 DELTA t⁴ where DELTA t is the depression ; of the freezing point of

  10. High-freezing-point fuels used for aviation turbine engines

    NASA Technical Reports Server (NTRS)

    Friedman, R.

    1979-01-01

    Broadened-specification aviation fuels could be produced from a greater fraction of crude source material with improvements in fuel supply and price. These fuels, particularly those with increased final boiling temperatures, would have higher freezing temperatures than current aviation turbine fuels. The higher-freezing-point fuels can be substituted in the majority of present commercial flights, since temperature data indicate that in-flight fuel temperatures are relatively mild. For the small but significant fraction of commercial flights where low fuel temperatures make higher freezing-point fuel use unacceptable, adaptations to the fuel or fuel system may be made to accommodate this fuel. Several techniques are discussed. Fuel heating is the most promising concept. One simple system design uses existing heat rejection from the fuel-lubricating oil cooler, another uses an engine-driven generator for electrical heating. Both systems offer advantages that outweigh the obvious penalties.

  11. High freezing point fuels used for aviation turbine engines

    NASA Technical Reports Server (NTRS)

    Friedman, R.

    1979-01-01

    Broadened-specification aviation fuels could be produced from a greater fraction of crude source material with improvements in fuel supply and price. These fuels, particularly those with increased final boiling temperatures, would have higher freezing temperatures than current aviation turbine fuels. For the small but significant fraction of commercial flights where low fuel temperatures make higher freezing-point fuel use unacceptable, adaptations to the fuel or fuel system may be made to accommodate this fuel. Several techniques are discussed. Fuel heating is the most promising concept. One simple design uses existing heat rejection from the fuel-lubricating oil cooler, another uses an engine-driven generator for electrical heating.

  12. Design and evaluation of aircraft heat source systems for use with high-freezing point fuels

    NASA Technical Reports Server (NTRS)

    Pasion, A. J.

    1979-01-01

    The objectives were the design, performance and economic analyses of practical aircraft fuel heating systems that would permit the use of high freezing-point fuels on long-range aircraft. Two hypothetical hydrocarbon fuels with freezing points of -29 C and -18 C were used to represent the variation from current day jet fuels. A Boeing 747-200 with JT9D-7/7A engines was used as the baseline aircraft. A 9300 Km mission was used as the mission length from which the heat requirements to maintain the fuel above its freezing point was based.

  13. An Equipment to Measure the Freezing Point of Soils under Higher Pressure

    NASA Astrophysics Data System (ADS)

    Wang, Dayan; Guan, Hui; Wen, Zhi; Ma, Wei

    2014-05-01

    Soil freezing point is the highest temperature at which ice can be presented in the system and soil can be referred to as frozen. The freezing temperature of soil is an important parameter for solving many practical problems in civil engineering, such as evaluation of soil freezing depth, prediction of soil heaving, force of soil suction, etc. However, as the freezing temperature is always affected by many factors like soil particle size, mineral composition, water content and the external pressure endured by soils, to measure soil freezing point is a rather difficult task until now, not to mention the soil suffering higher pressure. But recently, with the artificial freezing technology widely used in the excavation of deep underground space, the frozen wall thickness is a key factor to impact the security and stability of deep frozen wall. To determine the freeze wall thickness, the location of the freezing front must be determined firstly, which will deal with the determination of the soil freezing temperature. So how to measure the freezing temperature of soil suffering higher pressure is an important problem to be solved. This paper will introduce an equipment which was developed lately by State Key Laboratory of Frozen Soil Engineering to measure the freezing-point of soils under higher pressure. The equipment is consisted of cooling and keeping temperature system, temperature sensor and data collection system. By cooling and keeping temperature system, not only can we make the higher pressure soil sample's temperature drop to a discretionary minus temperature, but also keep it and reduce the heat exchange of soil sample with the outside. The temperature sensor is the key part to our measurement, which is featured by high precision and high sensitivity, what is more important is that the temperature sensor can work in a higher pressure condition. Moreover, the major benefit of this equipment is that the soil specimen's loads can be loaded by any microcomputer control electron universal testing machines. All of above mentioned advantages of this equipment ensures one to catch up the moment soil turns from the thawed state into ice and enable one to determine the freezing point experimentally by recording the temperature-time history (cooling curve) at particular points within the sample used for analysis. Therefore, this equipment has excellent characteristics such as compact construction, convenient operation, high reliability and the measuring accuracy. The authors would like to thank the following agents for their financial supports: the National Natural Science Foundation (No.41071048),Hundred Talent Young Scientists program of the Chinese Academy of Sciences granted to Dr. Zhi Wen.

  14. Effects of impurities on the freezing plateau of the triple point of water

    NASA Astrophysics Data System (ADS)

    Yan, X.; Zhang, J. T.; Duan, Y.; Wang, W.; Hao, X.

    2013-09-01

    The influence of impurities on the shape of the freezing curves of the triple point of water (TPW) in three small TPW cells was investigated using the freezing curve analysis method. We describe the procedure for preparing outer ice mantles in small TPW cells, for obtaining freezing plateaus, and for comparing the results between the old cell (s/n: 021) and the new cells (s/n: 001 and s/n: 008). The experimental results show that the maximum influence of impurities on the observed phase-transition temperature of water in the cell (s/n: 021) is approximately 0.2 mK below the peak temperature of the freezing plateau during freezing. Also, jagged temperature fluctuations were observed near the end of the freezing plateau in the old cell. However, these phenomena did not appear in the freezing plateaus of the new small cells. The equilibrium temperature realized with the old cell is 2.3 mK lower than that of the new cells, possibly due to excessive residual air. Therefore, assessing the effects of impurities on the TPW using an outer sheath method similar to that used in obtaining the fixed points of other metals is useful. Additionally, an estimated total mole fraction impurity concentration can be determined using Raoult's Law and the first cryoscopic constant for water.

  15. Realization of the Temperature Scale in the Range from 234.3 K (Hg Triple Point) to 1084.62°C (Cu Freezing Point) in Croatia

    NASA Astrophysics Data System (ADS)

    Zvizdic, Davor; Veliki, Tomislav; Grgec Bermanec, Lovorka

    2008-06-01

    This article describes the realization of the International Temperature Scale in the range from 234.3 K (mercury triple point) to 1084.62°C (copper freezing point) at the Laboratory for Process Measurement (LPM), Faculty of Mechanical Engineering and Naval Architecture (FSB), University of Zagreb. The system for the realization of the ITS-90 consists of the sealed fixed-point cells (mercury triple point, water triple point and gallium melting point) and the apparatus designed for the optimal realization of open fixed-point cells which include the gallium melting point, tin freezing point, zinc freezing point, aluminum freezing point, and copper freezing point. The maintenance of the open fixed-point cells is described, including the system for filling the cells with pure argon and for maintaining the pressure during the realization.

  16. Evaluation of methods for rapid determination of freezing point of aviation fuels

    NASA Technical Reports Server (NTRS)

    Mathiprakasam, B.

    1982-01-01

    Methods for identification of the more promising concepts for the development of a portable instrument to rapidly determine the freezing point of aviation fuels are described. The evaluation process consisted of: (1) collection of information on techniques previously used for the determination of the freezing point, (2) screening and selection of these techniques for further evaluation of their suitability in a portable unit for rapid measurement, and (3) an extensive experimental evaluation of the selected techniques and a final selection of the most promising technique. Test apparatuses employing differential thermal analysis and the change in optical transparency during phase change were evaluated and tested. A technique similar to differential thermal analysis using no reference fuel was investigated. In this method, the freezing point was obtained by digitizing the data and locating the point of inflection. Results obtained using this technique compare well with those obtained elsewhere using different techniques. A conceptual design of a portable instrument incorporating this technique is presented.

  17. Note: equation of state and the freezing point in the hard-sphere model.

    PubMed

    Robles, Miguel; López de Haro, Mariano; Santos, Andrés

    2014-04-01

    The merits of different analytical equations of state for the hard-sphere system with respect to the recently computed high-accuracy value of the freezing-point packing fraction are assessed. It is found that the Carnahan-Starling-Kolafa and the branch-point approximant equations of state yield the best performance. PMID:24712819

  18. Note: Equation of state and the freezing point in the hard-sphere model

    NASA Astrophysics Data System (ADS)

    Robles, Miguel; López de Haro, Mariano; Santos, Andrés

    2014-04-01

    The merits of different analytical equations of state for the hard-sphere system with respect to the recently computed high-accuracy value of the freezing-point packing fraction are assessed. It is found that the Carnahan-Starling-Kolafa and the branch-point approximant equations of state yield the best performance.

  19. A Four-Zone Furnace for Realization of Silver and Gold Freezing Points

    NASA Astrophysics Data System (ADS)

    Ripple, D. C.; Garrity, K. M.; Meyer, C. W.

    2003-09-01

    Recently, the Thermocouple Calibration Laboratory at the National Institute of Standards and Technology has used sodium heat-pipe furnaces for the realization of ITS-90 freezing points of aluminum, silver, and gold. When using a fixed-point cell mounted in a long silica-glass tube that extends to ambient temperature at the top of the furnace, we have observed significant thermal gradients along the well of the fixed-point cell, with the top of the well up to 0.1 K colder than the bottom. Furthermore, the heat-pipe lifetime is limited when used at the gold point (1064.18 °C) for more than a few hundred hours. To address these problems, we have designed and built a four-zone furnace based on a temperature-controlled, graphite isothermal block, suspended inside a three-zone tube furnace. The three-zone furnace is of a commercial design. The graphite block is enclosed in an alloy 600 (Inconel) can, allowing the graphite to be maintained in an argon atmosphere. The argon pressure is maintained at one atmosphere at all temperatures, thereby greatly reducing the stress on the can. Heaters in intimate contact with the can allow temperature control of the fourth inner zone to high accuracy. In this paper, the measured thermal stability and uniformity achieved with this furnace are presented. We also give results of test freezes of a silver freezing-point cell.

  20. Multiple Freezing Points as a Test for Viability of Plant Stems in the Determination of Frost Hardiness 1

    PubMed Central

    McLeester, R. C.; Weiser, C. J.; Hall, T. C.

    1969-01-01

    A technique is presented for a simple, rapid, and reliable means of determining the viability of plant tissue subjected to freezing temperatures. Freezing curves of excised stems of Cornus stolonifera Michx., and several other genera were studied. Tissue temperature was recorded during freezing of plant stem sections. The heat of crystallization deflected the resultant freezing curves at points where tissue froze. Living stem sections of all genera studied revealed 2 freezing points, while dead tissue exhibited only 1. The influence of variables such as moisture content, sample size, thermocouple placement, and cooling rate on freezing curves was analyzed. Stem samples wrapped in moisture-proof film with a thermocouple inserted into the pith were frozen to a predetermined test temperature, thawed, and subjected to a second freezing cycle. The presence or absence of 2 freezing points in the second freezing cycle was used as a criterion for establishing viability. The results were immediately available and identical to results from regrowth tests which took about 20 days. PMID:16657031

  1. Melting point depression of Al clusters generated during the early stages of film growth: Nanocalorimetry measurements

    E-print Network

    Allen, Leslie H.

    Melting point depression of Al clusters generated during the early stages of film growth in microelectronics: i melt- ing point depression as related to the Al reflow process,7­10 ii coalescence during been learned about the size-dependent melting point depression in recent times. Studies in model

  2. When hot water freezes before cold

    E-print Network

    J. I. Katz

    2006-04-27

    I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. They are concentrated ahead of the freezing front by zone refining in water that has not been heated, reduce the temperature of the freezing front, and thereby reduce the temperature gradient and heat flux, slowing the progress of the front. I present a simple calculation of this effect, and suggest experiments to test this hypothesis.

  3. Development of modulated optical transmission system to determinate the cloud and freezing points in biofuels

    NASA Astrophysics Data System (ADS)

    Jaramillo-Ochoa, Liliana; Ramirez-Gutierrez, Cristian F.; Sánchez-Moguel, Alonso; Acosta-Osorio, Andrés; Rodriguez-Garcia, Mario E.

    2015-01-01

    This work is focused in the development of a modulated optical transmission system with temperature control to determine the thermal properties of biodiesels such as the cloud and freezing points. This system is able to determine these properties in real time without relying on the operator skills as indicated in the American Society for Testing Materials (ASTM) norms. Thanks to the modulation of the incident laser, the noise of the signal is reduced and two information channels are generated: amplitude and phase. Lasers with different wavelengths can be used in this system but the sample under study must have optical absorption at the wavelength of the laser.

  4. Development of modulated optical transmission system to determinate the cloud and freezing points in biofuels.

    PubMed

    Jaramillo-Ochoa, Liliana; Ramirez-Gutierrez, Cristian F; Sánchez-Moguel, Alonso; Acosta-Osorio, Andrés; Rodriguez-Garcia, Mario E

    2015-01-01

    This work is focused in the development of a modulated optical transmission system with temperature control to determine the thermal properties of biodiesels such as the cloud and freezing points. This system is able to determine these properties in real time without relying on the operator skills as indicated in the American Society for Testing Materials (ASTM) norms. Thanks to the modulation of the incident laser, the noise of the signal is reduced and two information channels are generated: amplitude and phase. Lasers with different wavelengths can be used in this system but the sample under study must have optical absorption at the wavelength of the laser. PMID:25638112

  5. Prospective Chemistry Teachers' Misconceptions about Colligative Properties: Boiling Point Elevation and Freezing Point Depression

    ERIC Educational Resources Information Center

    Pinarbasi, Tacettin; Sozbilir, Mustafa; Canpolat, Nurtac

    2009-01-01

    This study aimed at identifying prospective chemistry teachers' misconceptions of colligative properties. In order to fulfill this aim, a diagnostic test composed of four open-ended questions was used. The test was administered to seventy-eight prospective chemistry teachers just before qualifying to teaching in secondary schools. Nine different…

  6. Realization of the Temperature Scale in the Range from 234.3 K (Hg Triple Point) to 1084.62°C (Cu Freezing Point) in Croatia

    Microsoft Academic Search

    Davor Zvizdic; Tomislav Veliki; Lovorka Grgec Bermanec

    2008-01-01

    This article describes the realization of the International Temperature Scale in the range from 234.3 K (mercury triple point)\\u000a to 1084.62°C (copper freezing point) at the Laboratory for Process Measurement (LPM), Faculty of Mechanical Engineering and\\u000a Naval Architecture (FSB), University of Zagreb. The system for the realization of the ITS-90 consists of the sealed fixed-point\\u000a cells (mercury triple point, water triple

  7. Estimating the influence of impurities on the freezing point of tin

    NASA Astrophysics Data System (ADS)

    Fellmuth, Bernd; Hill, Kenneth D.

    2006-02-01

    The sum of individual estimates (SIE) and the overall maximum estimate (OME) are two methods recommended to estimate the influence of impurities on the temperatures of the liquid-solid phase transformations of high-purity substances. The methods are discussed starting with the basic crystallographic facts, and their application is demonstrated in detail by applying them to the freezing point of tin as a first example. The SIE method leads to a temperature correction with a corresponding uncertainty while the OME method yields only an uncertainty that is, perhaps not unexpectedly, larger than that of the SIE approach. The necessary sensitivity coefficients (derivatives of the liquidus lines) are tabulated, together with the equilibrium distribution coefficients. Other than the necessity of obtaining a complete elemental analysis of the fixed-point material using glow discharge mass spectrometry (or other suitable techniques), there remain no technical barriers to adopting the preferred SIE method. While the use of the method, and particularly the application of a temperature correction to account for the impurity influence, requires a paradigm shift within the thermometry community, improved interoperability and harmonization of approach are highly desirable goals. The SIE approach maximizes the application of scientific knowledge and represents the best chance of achieving these common goals.

  8. Supercooling Point Plasticity During Cold Storage in the Freeze-tolerant Sugarbeet Root Maggot Tetanops myopaeformis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sugarbeet root maggot, Tetanops myopaeformis (Röder), overwinters as a freeze-tolerant 3rd instar larva. While most larvae are thought to overwinter for only one year, some may exhibit prolonged diapause in the field. In the laboratory, they can live for over five years using a combination of ...

  9. Depression

    MedlinePLUS

    ... and negative thinking worse. Back Continue Depression Can Go Unrecognized People with depression may not realize they ... themselves or who have eating disorders or who go through extreme mood changes may have unrecognized depression. ...

  10. Molecular Dynamics Study of Freezing Point and Solid-Liquid Interfacial Free Energy of Stockmayer Fluids

    SciTech Connect

    Wang, J. [University of Nebraska, Lincoln; Apte, Pankaj [Indian Institute of Technology, Kanpur; Morris, James R [ORNL; Zeng, X.C. [University of Nebraska, Lincoln

    2013-01-01

    Freezing temperatures of Stockmayer fluids with different dipolar strength at zero pressure are estimated and computed using three independent molecular-dynamics (MD) simulation methods, namely, the superheating-undercooling method, the constant-pressure and constant-temperature (NPT) two phase coexistence method, and the constant-pressure and constant-enthalpy (NPH) coexistence method. The best estimate of the freezing temperature (in reduced unit) for the Stockmayer (SM) fluid with a reduced dipole moment is 0.656 0.001, 0.726 0.002 and 0.835 0.005, respectively. The freezing temperature increases with the dipolar strength. The solid-liquid interfacial free energies of the (111), (110) and (100) interface are calculated for the first time using two independent methods, namely, the cleaving-wall method and the interfacial fluctuation method. Both methods predict that the interfacial free energy increases with the dipole moment. Although the interfacial fluctuation method suggests a weaker interfacial anisotropy, particularly for strongly dipolar SM fluids, both methods predicted the same trend of interfacial anisotropy, that is, .

  11. Detecting Critical Decision Points in Psychotherapy and Psychotherapy + Medication for Chronic Depression

    PubMed Central

    Steidtmann, Dana; Manber, Rachel; Blasey, Christine; Markowitz, John C.; Klein, Daniel N.; Rothbaum, Barbara O.; Thase, Michael E.; Kocsis, James H.; Arnow, Bruce A.

    2014-01-01

    Objective To quantify clinical decision points for identifying depression treatment non-remitters prior to end-of-treatment. Method Data come from the psychotherapy arms of a randomized clinical trial for chronic depression. Participants (n=352; 65.6% female; 92.3% White; mean age = 44.3 years) received 12 weeks of Cognitive Behavioral Analysis System of Psychotherapy (CBASP) or CBASP plus an antidepressant medication. In half of the sample, receiver operating curve (ROC) analyses were used to identify efficient percent symptom reduction cut points on the Inventory of Depressive Symptoms-Self Report (IDS-SR) for predicting end-of-treatment nonremission based on the Hamilton Rating Scale for Depression (HRSD). Sensitivity, specificity, predictive values and Cohen’s kappa for identified cut points were calculated using the remaining half of the sample. Results Percent IDS-SR symptom reduction at weeks 6 and 8 predicted end of treatment HRSD remission status in both the combined treatment (week 6 cut point = 50.0%, Cohen’s kappa = .42; week 8 cut point = 54.3%, Cohen’s kappa = .45), and psychotherapy only (week 6 cut point = 60.7%, Cohen’s kappa = .41; week 8 cut point = 48.7%, Cohen’s kappa = .49). Week 8 was more reliable for identifying nonremitters in psychotherapy only treatment. Conclusions Those with chronic depression who will not remit in structured, time-limited psychotherapy for depression, either alone or in combination with antidepressant medication, are identifiable prior to end-of-treatment. Findings provide an operationalized strategy for designing adaptive psychotherapy interventions. PMID:23750462

  12. Depressants

    MedlinePLUS

    ... GHB and Rohypnol® are also misused to facilitate sexual assault. Affect on mind Depressants used therapeutically do what ... GHB and Rohypnol® are also misused to facilitate sexual assault. Affect on mind Depressants used therapeutically do what ...

  13. Depression

    MedlinePLUS

    ... young adults to take antidepressants? Can I take St. John's wort to treat depression? How can I help myself ... their website . Return to top Can I take St. John's wort to treat depression? St. John's wort is a ...

  14. Depression

    MedlinePLUS

    ... future episodes for certain people at high risk. Psychotherapy: Psychotherapy , or “talk therapy,” is sometimes used alone for ... of mild depression; for moderate to severe depression. Psychotherapy is often used in along with antidepressant medications. ...

  15. Size-dependent melting point depression of nanostructures: Nanocalorimetric measurements

    Microsoft Academic Search

    M. Zhang; M. Yu. Efremov; F. Schiettekatte; E. A. Olson; A. T. Kwan; S. L. Lai; T. Wisleder; J. E. Greene; L. H. Allen

    2000-01-01

    The melting behavior of 0.1-10-nm-thick discontinuous indium films formed by evaporation on amorphous silicon nitride is investigated by an ultrasensitive thin-film scanning calorimetry technique. The films consist of ensembles of nanostructures for which the size dependence of the melting temperature and latent heat of fusion are determined. The relationship between the nanostructure radius and the corresponding melting point and latent

  16. Depression, posttraumatic stress disorder, and grade point average among student servicemembers and veterans.

    PubMed

    Bryan, Craig J; Bryan, AnnaBelle O; Hinkson, Kent; Bichrest, Michael; Ahern, D Aaron

    2014-01-01

    The current study examined relationships among self-reported depression severity, posttraumatic stress disorder (PTSD) symptom severity, and grade point average (GPA) among student servicemembers and veterans. We asked 422 student servicemembers and veterans (72% male, 86% Caucasian, mean age = 36.29 yr) to complete an anonymous online survey that assessed self-reported GPA, depression severity, PTSD severity, and frequency of academic problems (late assignments, low grades, failed exams, and skipped classes). Female respondents reported a slightly higher GPA than males (3.56 vs 3.41, respectively, p = 0.01). Depression symptoms (beta weight = -0.174, p = 0.03), male sex (beta weight = 0.160, p = 0.01), and younger age (beta weight = 0.155, p = 0.01) were associated with lower GPA but not PTSD symptoms (beta weight = -0.040, p = 0.62), although the interaction of depression and PTSD symptoms showed a nonsignificant inverse relationship with GPA (beta weight = -0.378, p = 0.08). More severe depression was associated with turning in assignments late (beta weight = 0.171, p = 0.03), failed exams (beta weight = 0.188, p = 0.02), and skipped classes (beta weight = 0.254, p = 0.01). The relationship of depression with self-reported GPA was mediated by frequency of failed examns. Results suggest that student servicemembers and veterans with greater emotional distress also report worse academic performance. PMID:25436619

  17. The influence of ionizable and non-ionizable compounds in milk upon its freezing point 

    E-print Network

    Pinkerton, Frank

    1955-01-01

    ooatoat bye Chafrnan ot Cossatttoe Eoal of Dopartaont or Stukont visor lngust 195$ TiBLR OP COSTXXTS Page IXTRODUCT I OX . . RXVIXW Oy LITXRLTURX. XXPXRIMXRTdL PROCXDUBX. RXSUI TS, Tho Iaflueaoe of Mastitis oa the pressing Point of Milk, Per... tho routine Babcock fat tost to determine solids not-fat content of milk (Sommer, 1948). 11 The Influeaoe of Mastitis on the Preening Point of Milk, Per Coat Laotoso and Canduotivity Samples wore collected from iafocted quarters of eveniag milk...

  18. Depression.

    ERIC Educational Resources Information Center

    Strock, Margaret

    Approximately ten percent of the population suffers from a depressive illness each year. Although the economic cost is high, the cost in human suffering is immeasurable. To help educate the population about this disorder, this paper presents a definition of depression and its common manifestations. The symptoms that people often experience are…

  19. Depression

    MedlinePLUS

    ... and depression is usually a major contributing factor. Adults 65 and older have a suicide rate that is higher than the rate for ... somewhat lower than those for young and middle-aged women, rates among men 75 ... highest suicide rate in the United States. Types of Depression ...

  20. Freezing in confined geometries

    NASA Technical Reports Server (NTRS)

    Sokol, P. E.; Ma, W. J.; Herwig, K. W.; Snow, W. M.; Wang, Y.; Koplik, Joel; Banavar, Jayanth R.

    1992-01-01

    Results of detailed structural studies, using elastic neutron scattering, of the freezing of liquid O2 and D2 in porous vycor glass, are presented. The experimental studies have been complemented by computer simulations of the dynamics of freezing of a Lennard-Jones liquid in narrow channels bounded by molecular walls. Results point to a new simple physical interpretation of freezing in confined geometries.

  1. Freezing Fish and Shellfish.

    E-print Network

    Nickelson, Ranzell; Reddell, Annette

    1980-01-01

    contents may impart off-odors and off flavors to the flesh. Digestive enzymes and bacteria found in the intestinal fluids also can begin to digest the fish flesh before the product freezes. The dark flesh of fish is usually less stable in frozen... means of preserving the fresh-caught quality of fish and shellfish. Why Freeze? Freezing preserves foods by lowering their tem peratures to a point not conducive to bacterial growth and natural enzyme action. Many spoilage bacteria are destroyed...

  2. Negative pressures and melting point depression in oxide-coated liquid metal droplets

    NASA Technical Reports Server (NTRS)

    Spaepen, F.; Turnbull, D.

    1979-01-01

    Negative pressures and melting point depression in oxide-coated liquid metal droplets are studied. The calculation presented show the existence of large negative pressures when the oxide coating is thick enough. The change in the melting point caused by these negative pressures should be considered in studies of homogeneous crystal nucleation. Furthermore, since the negative pressure raises the entropy of the melt, it increases the entropy loss at the crystal-melt interface; the resulting increase of the surface tension could have a large effect on the homogeneous nucleation frequency.

  3. Evaluation of the MilkoScan FT 6000 Milk Analyzer for Determining the Freezing Point of Goat's Milk Under Different Analytical Conditions

    Microsoft Academic Search

    A. Sánchez; D. Sierra; C. Luengo; J. C. Corrales; C. de la Fe; C. T. Morales; A. Contreras; C. Gonzalo

    2007-01-01

    The aim of this research was to evaluate the Milko- Scan FT 6000 (Foss Electric, Hillerød, Denmark) for determining the freezing point (FP) of goat's milk under different analytical conditions. The FP was determined in duplicate in 1,800 milk aliquots obtained from 45 bulk tank milk samples from 10 Murciano-Granadina goat herds, using the MilkoScan method and a reference thermistor

  4. Depression

    NSDL National Science Digital Library

    Patient Education Institute

    This patient education program explains depression, the symptoms, causes and available treatment options. This is a MedlinePlus Interactive Health Tutorial from the National Library of Medicine, designed and developed by the Patient Education Institute. NOTE: The tutorial requires a special Flash plug-in, version 4 or above. If you do not have Flash, you will be prompted to obtain a free download of the software before you start the tutorial. You will also need an Acrobat Reader, available as a free download, in order to view the Reference Summary.

  5. Melting Point Depression and Kinetic Effects of Cooling on Crystallization in Poly(vinylidene fluoride)Poly(methyl methacrylate) Mixtures

    Microsoft Academic Search

    T. Nishi; T. T. Wang

    1975-01-01

    Thermal analysis of solution cast mixtures of poly(viny1idene fluoride) (PVF2) and poly(methy1 methacrylate) (PMMA) has been carried out with various programmed temperature profiles. Results from experi- ments conducted in a quasi-equilibrium state show that PVF:! crystallizes in the mixture upon cooling. Further- more, depressions were observed in the melting and the crystallization temperatures. The melting point depression phenomenon is found

  6. Experimental and analytical investigation of a freezing point depressant fluid ice protection system. M.S. Thesis. Final Report

    NASA Technical Reports Server (NTRS)

    Albright, A. E.

    1984-01-01

    A glycol-exuding porous leading edge ice protection system was tested in the NASA Icing Research Tunnel. Stainless steel mesh, laser drilled titanium, and composite panels were tested on two general aviation wing sections. Two different glycol-water solutions were evaluated. Minimum glycol flow rates required for anti-icing were obtained as a function of angle of attack, liquid water content, volume median drop diameter, temperature, and velocity. Ice accretions formed after five minutes of icing were shed in three minutes or less using a glycol fluid flow equal to the anti-ice flow rate. Two methods of predicting anti-ice flow rates are presented and compared with a large experimental data base of anti-ice flow rates over a wide range of icing conditions. The first method presented in the ADS-4 document typically predicts flow rates lower than the experimental flow rates. The second method, originally published in 1983, typically predicts flow rates up to 25 percent higher than the experimental flow rates. This method proved to be more consistent between wing-panel configurations. Significant correlation coefficients between the predicted flow rates and the experimental flow rates ranged from .867 to .947.

  7. KEY COMPARISON: Final report on comparison COOMET.TK3: Regional comparisons of the national standards of temperature in the range from the triple point of water to the freezing temperature of zinc

    Microsoft Academic Search

    A. I. Pokhodun; A. G. Ivanova

    2008-01-01

    The COOMET.T-K3 comparison is the regional comparison of the defining fixed points realization in the range from the triple point of water to the freezing point of zinc. Four national metrology institutes---VNIIM (pilot), SMU, BelGIM and NNC IM---took part in the COOMET regional comparisons. At the first stage the cells of fixed points of the national metrology institutes were used

  8. Bjorken expansion with gradual freeze out

    E-print Network

    V. K. Magas; L. P. Csernai; E. Molnar

    2007-02-27

    The freeze out of the expanding systems, created in relativistic heavy ion collisions, will be discussed. We combine kinetic freeze out equations with Bjorken type system expansion into a unified model. Such a model is a more physical generalization of the earlier simplified non-expanding freeze out models. We shall see that the basic freeze out features, pointed out in the earlier works, are not smeared out by the expansion.

  9. A genome-wide association study points to multiple loci predicting antidepressant treatment outcome in depression

    PubMed Central

    Binder, Elisabeth B.; Bettecken, Thomas; Uhr, Manfred; Ripke, Stephan; Kohli, Martin A.; Hennings, Johannes M.; Horstmann, Sonja; Kloiber, Stefan; Menke, Andreas; Bondy, Brigitta; Rupprecht, Rainer; Domschke, Katharina; Baune, Bernhard T.; Arolt, Volker; Rush, A. John; Holsboer, Florian; Müller-Myhsok, Bertram

    2015-01-01

    Context Efficacy of antidepressant treatment in depression is unsatisfactory as one in three patients does not fully recover even after several treatment trials. Genetic factors and clinical characteristics contribute to the failure of a favorable treatment outcome. Objective To identify genetic and clinical determinants of antidepressant treatment outcome in depression. Design Genome-wide pharmacogenetic association study with two independent replication samples. Setting We performed a genome-wide association (GWA) study in patients from the Munich-Antidepressant-Response-Signature (MARS) project and in pooled DNA from an independent German replication sample. A set of 328 single nucleotide polymorphisms (SNPs) highly related to outcome in both GWA studies was genotyped in a sample of the Sequenced-Treatment-Alternatives-to-Relieve-Depression (STAR*D) study. Participants 339 inpatients suffering from a depressive episode (MARS sample), further 361 depressed inpatients (German replication sample), and 832 outpatients with major depression (STAR*D sample). Main Outcome Measures We generated a multi-locus genetic variable describing the individual number of alleles of the selected SNPs associated with beneficial treatment outcome in the MARS sample (“response” alleles) to evaluate additive genetic effects on antidepressant treatment outcome. Results Multi-locus analysis revealed a significant contribution of a binary variable categorizing patients as carriers of a high vs. low number of response alleles in predicting antidepressant treatment outcome in both samples, MARS and STAR*D. In addition, we observed that patients with a comorbid anxiety disorder in combination with a low number of response alleles showed the least favorable outcome. Conclusion Our results demonstrate the importance of multiple genetic factors in combination with clinical features to predict antidepressant treatment outcome underscoring the multifactorial nature of this trait. PMID:19736353

  10. Autobiographical Memory and Depression in the Later Age: The Bump Is a Turning Point

    ERIC Educational Resources Information Center

    Gidron, Yori; Alon, Shirly

    2007-01-01

    This preliminary study integrated previous findings of the distribution of autobiographical memories in the later age according to their age of occurrence, with the overgeneral memory bias predictive of depression. Twenty-five non-demented, Israeli participants between 65-89 years of age provided autobiographical memories to 4 groups of word cues…

  11. Size-dependent melting point depression of nanostructures: Nanocalorimetric measurements M. Zhang, M. Yu. Efremov, F. Schiettekatte, E. A. Olson, A. T. Kwan, S. L. Lai, T. Wisleder,

    E-print Network

    Allen, Leslie H.

    Size-dependent melting point depression of nanostructures: Nanocalorimetric measurements M. Zhang and the corresponding melting point and latent heat is deduced solely from experimental results i.e., with no assumed by transmission electron microscopy. It is shown that the melting point of the investigated indium nanostructures

  12. Wetting and freezing of hexadecane on an aqueous surfactant solution: triple point in a 2-D film.

    PubMed

    Matsubara, H; Ohtomi, E; Aratono, M; Bain, Colin D

    2008-09-18

    Wetting of water by hexadecane has been investigated by ellipsometry as a function of the concentration of the cationic surfactant dodecyltrimethylammonium bromide (DTAB) in the aqueous phase and temperature. Three phases are identified: a 2-D gas of hexadecane molecules and DTAB molecules, a 2-D liquid comprising a mixed monolayer of hexadecane and DTAB, and a 2-D 'solid' phase. Evidence is presented to support the hypothesis that the liquid-solid phase transition is actually a wetting transition in which a surface-frozen layer of pure hexadecane wets the liquid-like mixed monolayer of hexadecane and DTAB. The triple point, at which the three phases coexist, is located at a temperature of 17.3 degrees C and DTAB concentration of 0.75 mmol kg (-1). The slopes of the three phase boundaries are analyzed thermodynamically. PMID:18729394

  13. Metabolic engineering of oilseed crops to produce high levels of novel acetyl glyceride oils with reduced viscosity, freezing point and calorific value.

    PubMed

    Liu, Jinjie; Rice, Adam; McGlew, Kathleen; Shaw, Vincent; Park, Hyunwoo; Clemente, Tom; Pollard, Mike; Ohlrogge, John; Durrett, Timothy P

    2015-08-01

    Seed oils have proved recalcitrant to modification for the production of industrially useful lipids. Here, we demonstrate the successful metabolic engineering and subsequent field production of an oilseed crop with the highest accumulation of unusual oil achieved so far in transgenic plants. Previously, expression of the Euonymus alatus diacylglycerol acetyltransferase (EaDAcT) gene in wild-type Arabidopsis seeds resulted in the accumulation of 45 mol% of unusual 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) in the seed oil (Durrett et al., 2010 PNAS 107:9464). Expression of EaDAcT in dgat1 mutants compromised in their ability to synthesize regular triacylglycerols increased acetyl-TAGs to 65 mol%. Camelina and soybean transformed with the EaDAcT gene accumulate acetyl-triacylglycerols (acetyl-TAGs) at up to 70 mol% of seed oil. A similar strategy of coexpression of EaDAcT together with RNAi suppression of DGAT1 increased acetyl-TAG levels to up to 85 mol% in field-grown transgenic Camelina. Additionally, total moles of triacylglycerol (TAG) per seed increased 20%. Analysis of the acetyl-TAG fraction revealed a twofold reduction in very long chain fatty acids (VLCFA), consistent with their displacement from the sn-3 position by acetate. Seed germination remained high, and seedlings were able to metabolize the stored acetyl-TAGs as rapidly as regular triacylglycerols. Viscosity, freezing point and caloric content of the Camelina acetyl-TAG oils were reduced, enabling use of this oil in several nonfood and food applications. PMID:25756355

  14. Stability against freezing of aqueous solutions on early Mars.

    PubMed

    Fairén, Alberto G; Davila, Alfonso F; Gago-Duport, Luis; Amils, Ricardo; McKay, Christopher P

    2009-05-21

    Many features of the Martian landscape are thought to have been formed by liquid water flow and water-related mineralogies on the surface of Mars are widespread and abundant. Several lines of evidence, however, suggest that Mars has been cold with mean global temperatures well below the freezing point of pure water. Martian climate modellers considering a combination of greenhouse gases at a range of partial pressures find it challenging to simulate global mean Martian surface temperatures above 273 K, and local thermal sources cannot account for the widespread distribution of hydrated and evaporitic minerals throughout the Martian landscape. Solutes could depress the melting point of water in a frozen Martian environment, providing a plausible solution to the early Mars climate paradox. Here we model the freezing and evaporation processes of Martian fluids with a composition resulting from the weathering of basalts, as reflected in the chemical compositions at Mars landing sites. Our results show that a significant fraction of weathering fluids loaded with Si, Fe, S, Mg, Ca, Cl, Na, K and Al remain in the liquid state at temperatures well below 273 K. We tested our model by analysing the mineralogies yielded by the evolution of the solutions: the resulting mineral assemblages are analogous to those actually identified on the Martian surface. This stability against freezing of Martian fluids can explain saline liquid water activity on the surface of Mars at mean global temperatures well below 273 K. PMID:19458717

  15. Preservation of flavor in freeze dried green beans

    NASA Technical Reports Server (NTRS)

    Huber, C. S.; Heidelbaugh, N. D.; Davis, D.

    1973-01-01

    Before freeze drying, green beans are heated to point at which their cell structure is altered. Beans freeze dried with altered cell structure have improved rehydration properties and retain color, flavor, and texture.

  16. Evaluation of the MilkoScan FT 6000 milk analyzer for determining the freezing point of goat's milk under different analytical conditions.

    PubMed

    Sánchez, A; Sierra, D; Luengo, C; Corrales, J C; de la Fe, C; Morales, C T; Contreras, A; Gonzalo, C

    2007-07-01

    The aim of this research was to evaluate the Milko-Scan FT 6000 (Foss Electric, Hillerød, Denmark) for determining the freezing point (FP) of goat's milk under different analytical conditions. The FP was determined in duplicate in 1,800 milk aliquots obtained from 45 bulk tank milk samples from 10 Murciano-Granadina goat herds, using the MilkoScan method and a reference thermistor cryoscopy method (Advanced Instrument Inc., Norwood, MA). Five different preservation strategies--no preservative, preservation with azidiol (0.006 or 0.018 g of sodium azide/100 mL), and preservation with bronopol (0.020 or 0.040 g/100 mL)--were then used to preserve the milk. For each preservation strategy, 8 different amounts of water were added (0, 1, 2, 3, 4, 5, 6, or 7% total volume). The results obtained with each method under these 40 analytical conditions were examined by comparison of means, comparison of the standard deviations of repeatability (s(r) and its relative value s(r)%), and a regression analysis. Under most analytical conditions, the FP was recorded as lower by the MilkoScan method, with a mean difference of 1.5 m degrees C compared with the reference method. Both methods showed similar repeatabilities (the overall s(r)% was 0.22% for the MilkoScan method and 0.20% for the reference method). In comparisons of the 2 methods, the highest regression coefficients were obtained with aliquots containing >3% added water. The best regression coefficients (0.85 to 1.02) were obtained for milk samples preserved with bronopol at 0.020 g/100 mL. These results allow the MilkoScan method to be used with goat's milk for screening purposes. The factors of added water, preservative, analytical method, lactose concentration, and the effect of the bulk tank milk sample within each lactose group contributed significantly to the observed variation in FP. For practical purposes, either of the bronopol concentrations could be used when determining the FP of goat's milk with the methods tested. However, the increase in the concentration of sodium azide in the azidiol formula contributed to an important reduction in the FP recorded. Thus, the type and concentration of preservative should be taken into account when interpreting FP values. PMID:17582097

  17. Vapor Pressure Plus: An Experiment for Studying Phase Equilibria in Water, with Observation of Supercooling, Spontaneous Freezing, and the Triple Point

    ERIC Educational Resources Information Center

    Tellinghuisen, Joel

    2010-01-01

    Liquid-vapor, solid-vapor, and solid-liquid-vapor equilibria are studied for the pure substance water, using modern equipment that includes specially fabricated glass cells. Samples are evaporatively frozen initially, during which they typically supercool to -5 to -10 [degrees]C before spontaneously freezing. Vacuum pumping lowers the temperature…

  18. An Improved Microscope Stage for Direct Observation of Freezing and Freeze Drying

    Microsoft Academic Search

    Steven L. Nail; Lih-Min Her; Christopher P. B. Proffitt; Lisa L. Nail

    1994-01-01

    A microscope stage for observation of freezing and freeze drying is described. The stage uses thermoelectric (Peltier) heaters configured in two stages, with circulating fluid as a heat sink on the high temperature side. Lowest attainable sample temperature is about -47°C. Principal advantages of this system are closed-loop control of stage temperature, rapid response to changes in temperature set point,

  19. Freezing rate and duration determine the physiological response of intertidal fucoids to freezing

    Microsoft Academic Search

    G. A. Pearson; I. R. Davison

    1993-01-01

    Differential thermal analysis (DTA) was used to measure the freezing temperature of nine species of red brown intertidal macroalgae from the coast of Maine, USA in 1991. Using slow and rapid cooling rates approximating those found in the field for Ascophyllum nodosum (L.) Le Jol. we found that, for a given rate, the freezing points of all species were similar:

  20. Fish With Nature's Anti-freeze

    NSDL National Science Digital Library

    Using this material, students will discover that under special experimental conditions, fish have been observed functioning in ice-free cold salt water at a temperature of -6 degrees Centigrade. Research has found that these fish have eight types of anti-freeze molecules which bathe the interior surface of their skin, acting as a barrier to ice propagating in from outside. When the anti-freeze molecules are not present, ice filters through their skin at these temperatures and crystallizes (freezes) their blood and tissues. Students will experiment with lowering the freezing point of a substance, thus causing it to remain liquid at a temperature when it is normally solid. Students will compare their findings with facts about Antarctic ice-fish, which have bodily fluids that remain liquid at temperatures below freezing.

  1. Postpartum Depression

    MedlinePLUS

    ... postpartum depression occur? • What causes postpartum depression? • If I think I have postpartum depression, when should I see ... greatly increase the risk of postpartum depression. If I think I have postpartum depression, when should I see ...

  2. The Effects of Social Economic Status, Social Support, Gender, Ethnicity and Grade Point Average on Depression among College Students.

    ERIC Educational Resources Information Center

    Ndoh, Sunday; Scales, Josie

    Previous research has indicated that depression, the most common psychological disorder experienced by over 19 million Americans, can be related to such factors as ethnicity, social support, social economic status, academic achievement and gender. One hundred and sixty students from Johnson C. Smith University and Tennessee State University were…

  3. Surface freezing of n-octane nanodroplets

    NASA Astrophysics Data System (ADS)

    Modak, Viraj; Pathak, Harshad; Thayer, Mitchell; Singer, Sherwin; Wyslouzil, Barbara

    2013-05-01

    Surface freezing, at temperatures up to a few degrees above the equilibrium melting point, has been observed for intermediate chain length (16? i? 50) n-alkanes [B. M. Ocko, X. Z. Wu, E. B. Sirota, S. K. Sinha, O. Gang and M. Deutsch, Phys. Rev. E, 1997, 55, 3164-3182]. Our recent experimental results suggest that surface freezing is also the first step when highly supercooled nanodroplets of n-octane crystallize. Our data yield surface and bulk nucleation rates on the order of ˜1015/cm2.s and ˜1022/cm3.s, respectively. Complementary molecular dynamics simulations also show that the surface of the droplet freezes almost immediately, and freezing of the remainder of the droplet progresses in a layer-by-layer manner.

  4. Winter Depression

    NSDL National Science Digital Library

    A U.K. psychologist has developed a complex mathematical formula using seven variables to predict winter's emotional low point. The good news is the worst day of the year was last week; nonetheless, seasonal depression remains a problem for many. The first link (1) is to an article about the equation worked out by Dr. Cliff Arnall, who specializes in seasonal disorders at the University of Cardiff, Wales. The second link is to a WebMD page (2) about winter depression, often referred to as Seasonal Affective Disorder (SAD). The next link (3) is to a recent news story about the results of a five-year study that found, rather than antidepressant drug therapy or air ionizers, light box therapy is the best remedy for the seasonal condition. The fourth link is to a set of Frequently Asked Questions (4) about SAD offered by Columbia Presbyterian Medical Center in New York City. The fifth link, to the Winter Depression Research Group at the University of Tromso in Norway(5), explains why Norway is a natural SAD research laboratory. The next link is to a international portal site (6) maintained by medical professionals and researchers in the field of light therapy and biological rhythms. The final webpage(7), from Psychology Today, compares the symptoms of winter depression with summer depression.

  5. Freeze drying method

    SciTech Connect

    Coppa, N.V.; Stewart, P.; Renzi, E.

    1999-12-07

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser.

  6. Ponds Freeze in Winter -- Why Doesn't the Ocean?

    NSDL National Science Digital Library

    New England Aquarium

    2011-01-01

    In this activity, learners explore how salt water freezes in comparison to fresh water. Use this experiment to consider how pond animals survive cold winters in comparison to animals that live in the ocean. This resource includes information about freezing points as well as examples of how different animals respond to the winter cold.

  7. Antidepressants Ease Postpartum Depression

    MedlinePLUS

    ... depression and few studies to date have included women with severe depression," study co-author Kylee Trevillion, from King's College London, ... the Journal of the American Medical Association . The study's senior ... College London, pointed out that women who are breast-feeding need to let all ...

  8. Bjorken model with Freeze Out

    E-print Network

    V. K. Magas; L. P. Csernai

    2007-11-19

    The freeze out of the expanding systems, created in relativistic heavy ion collisions, is discussed. We combine Bjorken scenario with earlier developed freeze out equations into a unified model. The important feature of the proposed model is that physical freeze out is completely finished in a finite time, which can be varied from 0 (freeze out hypersurface) to infinity. The dependence of the post freeze out distribution function on this freeze out time will be studied. As an example model is completely solved and analyzed for the gas of pions.

  9. Potential benefits of health information technology for integrating physical and behavioral health care: perinatal depression as a case-in-point

    Microsoft Academic Search

    Ellen Burke Beckjord; Donna J Keyser; Dana Schultz; Susan L Lovejoy; Raymond Firth; Harold Alan Pincus

    2011-01-01

    Depression among pregnant and postpartum women (i.e., perinatal depression) is the number one complication of childbirth.\\u000a The Allegheny County Maternal Depression Initiative aimed to bridge gaps between physical and behavioral health care and improve\\u000a the capacity of local systems of care for identifying and treating women at high risk for perinatal depression. To achieve\\u000a these goals, the collaborative adopted a

  10. Fuel Cell Freeze Startup and Landscape of FC Freeze Patents

    E-print Network

    Patents · Top categories ­ Fuel cell stack (212) ­ Piping (104) ­ Solid electrolyte fuel cell (119Fuel Cell Freeze Startup and Landscape of FC Freeze Patents DOE Workshop on Fuel Cell Operations of PEM fuel cells from sub-freezing temperatures. Approach · Collect data/information through literature

  11. Freezing Poultry for Home Use 

    E-print Network

    Davis, Michael

    2006-08-31

    Purchasing fresh poultry in large packages and freezing it in quantities suitable for individual meals can stretch time and food dollars. Topics include packaging needs, cutting, storing and thawing instructions, and freezing pre-cooked meals....

  12. Freezing and thawing processes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seasonally frozen soil strongly influences runoff and erosion on large areas of land around the world. In many areas, rain or snowmelt on seasonally frozen soil is the single leading cause of severe runoff and erosion events. As soils freeze, ice blocks the soil pores, greatly diminishing the perm...

  13. Animal Anti-Freeze

    NSDL National Science Digital Library

    2012-06-26

    In this outdoor winter activity, learners search for and create hibernation sites that will protect gelatin "animals" from freezing. Learners come to understand that hibernating animals need to take care in selecting a sleeping spot that will provide protection from the winter cold.

  14. Freezing of triangulations

    NASA Astrophysics Data System (ADS)

    Kownacki, J.-P.

    2004-04-01

    Zero temperature dynamics of two dimensional triangulations of a torus with curvature energy is described. Numerical simulations strongly suggest that the model get frozen in metastable states, made of topological defects on flat surfaces, that group into clusters of same topological charge. It is conjectured that freezing is related to high temperature structure of baby universes.

  15. Modeling soil freezing dynamics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seasonally frozen soil strongly influences runoff and erosion on large areas of land around the world. In many areas, rain or snowmelt on seasonally frozen soil is the single leading cause of severe runoff and erosion events. As soils freeze, ice blocks the soil pores, greatly diminishing the permea...

  16. 7 CFR 58.621 - Freezing tunnels.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Freezing tunnels. 58.621 Section 58.621 Agriculture... Rooms and Compartments § 58.621 Freezing tunnels. Freezing tunnels for quick freezing at extremely low temperatures...

  17. 7 CFR 58.621 - Freezing tunnels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Freezing tunnels. 58.621 Section 58.621 Agriculture... Rooms and Compartments § 58.621 Freezing tunnels. Freezing tunnels for quick freezing at extremely low temperatures...

  18. 7 CFR 58.621 - Freezing tunnels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Freezing tunnels. 58.621 Section 58.621 Agriculture... Rooms and Compartments § 58.621 Freezing tunnels. Freezing tunnels for quick freezing at extremely low temperatures...

  19. 7 CFR 58.621 - Freezing tunnels.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Freezing tunnels. 58.621 Section 58.621 Agriculture... Rooms and Compartments § 58.621 Freezing tunnels. Freezing tunnels for quick freezing at extremely low temperatures...

  20. 7 CFR 58.621 - Freezing tunnels.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Freezing tunnels. 58.621 Section 58.621 Agriculture... Rooms and Compartments § 58.621 Freezing tunnels. Freezing tunnels for quick freezing at extremely low temperatures...

  1. Freeze-drying of proteins.

    PubMed

    Liu, Baolin; Zhou, Xinli

    2015-01-01

    Freeze-drying has become one of the most important processes for the preservation of biological products. This chapter provides protocols for freeze-drying of proteins and discusses the importance of formulation, cycle development, and validation. Specific formulations for stabilization of proteins are presented as well as advice on common problems with freeze-drying of proteins. PMID:25428023

  2. Freezing and Food Safety

    MedlinePLUS

    ... Administrative Forms Standard Forms Skip Navigation Z7_0Q0619C0JGR010IFST1G5B10H1 Web Content Viewer (JSR 286) Actions ${title} Loading... / Topics / ... Food Safety / Freezing and Food Safety Z7_0Q0619C0JGR010IFST1G5B10H3 Web Content Viewer (JSR 286) Actions ${title} Loading... Z7_ ...

  3. Freeze out of the expanding system

    E-print Network

    V. K. Magas; L. P. Csernai; E. Molnar

    2007-02-22

    The freeze out (FO) of the expanding systems, created in relativistic heavy ion collisions, is discussed. We start with kinetic FO model, which realizes complete physical FO in a layer of given thickness, and then combine our gradual FO equations with Bjorken type system expansion into a unified model. We shall see that the basic FO features, pointed out in the earlier works, are not smeared out by the expansion.

  4. Freeze Crystallization Processes: Efficiency by Flexibility 

    E-print Network

    Heist, J. A.; Barron, T. S.

    1983-01-01

    and aromatics have very close bOlllng pOlnts, so fractional distillation is not practical. Extraction with tetramethylene sulfone or tetraethylene glycol (TeEG) is the usual method used to separate the aromatics from the parafins. The aromatics...-20, 1983 ~ CRUDE BTX [25 WTY. DE-PARIFFINED @ EXTRACT [60 WTY. TETRAETHYLENE GLYCOL) EUTECTIC POINT 230 240 220 210 0 x: W t 200 190 180 (CONVENTIONAL REFINING) ? ? ? FIGURE 6 8TX FREEZE REFINING The first of these is illustrated...

  5. New Insights Into BDNF Signaling: Relevance to Major Depression and

    E-print Network

    Sibille, Etienne

    Major depressive disorder is a serious multifactorial mental illness that is characterizedEditorial New Insights Into BDNF Signaling: Relevance to Major Depression and Antidepressant Action of major depression, with the hope of developing more efficacious treatments. Emerging evidence points

  6. Freeze Branding Horses 

    E-print Network

    Householder, Doug; Webb, Gary; Wigington, Sam; Bruemmer, Jason

    2001-06-29

    (like a clear straw) from the GF. On colored horses, pigment (black, brown, red, yellow, etc.) is added from the CF below the skin to the clear hairshaft, which gives the hair its color. When the intensely cold iron used in freeze branding is placed... site contains no pigment and appears white. This is the desired result?a uniform, white brand. If the iron is pressed to the skin for a shorter period of time and/or with less pressure than required, some hairs grow in colored and some hairs grow...

  7. Freeze Branding Horses

    E-print Network

    Householder, Doug; Webb, Gary; Wigington, Sam; Bruemmer, Jason

    2001-06-29

    , simpli- f_ied drawing of one hair shaft with its color (pigment) producing follicle (CF) and its growth follicle (GF), both shown below the skin. Doug Householder 1 , Gary Webb 2 , Sam Wigington 3 and Jason Bruemmer 4 Freeze Branding Horses Figure 1. Hair... manager, Horse Center, Department of Animal Science, Texas A&M University. Texas AgriLife Extension Service ? Zerle L. Carpenter, Director ? The Texas A&M University System ? College Station, Texas Under normal circumstances hair grows as a clear shaft...

  8. Chronic Depression

    Microsoft Academic Search

    Lawrence P. Riso; Michael E. Thase

    While once of limited interest to the field, chronic depression is now recognized as a major public health problem (Howland, 1993). Not only is chronic depression common, representing 19% of all depressed patients (Keller & Hanks, 1995) and 6% in the community (Kessler et al., 1994), but it is also associated with considerable psychosocial impairment (Howland, 1993), and is extremely

  9. Depression in Coronary Artery Disease

    PubMed Central

    Safaie, Nasser; Jodati, Ahmad Reza; Raoofi, Mohammad; Khalili, Majid

    2012-01-01

    Introduction Depression is one of the Common psychological disorders. From the cognitive point of view, the unhealthy attitudes increase the severity of the depression. The aim of this study was to investigate depression and unhealthy attitudes in coronary patients hospitalized at Tabriz Shahid Madani Heart Center. Methods One hundred twenty eight hospitalized patients having myocardial Infarctions were studied regarding unhealthy attitudes, severity of depression and demographic data. Results The study showed a significant relation between unhealthy attitudes, BDI (Beck Depression Inventory) and severe depression. Moreover, a significant relation existed between gender and depression (P=0.0001). In addition, the level of education increased the intensity of unhealthy attitudes (P=0.0001). Several researches in both outside and inside Iran support the idea. Conclusion Based on present study and more other investigations, it can be suggested to provide the necessary elements and parameters such as antidepressant medication, psychologists, complementary treatment for coping with negative mood and its unwanted consequences. PMID:24250990

  10. Role of Heart and its Diseases in the Etiology of Depression According to Avicenna's Point of View and its Comparison with Views of Classic Medicine

    PubMed Central

    Yousofpour, Mohammad; Kamalinejad, Mohammad; Esfahani, Mohammad Mahdi; Shams, Jamal; Tehrani, Hassan Hoshdar; Bahrami, Mohsen

    2015-01-01

    Background: Depression is one of the most important medical problems in today's world; despite its high prevalence, its causes unfortunately remain not fully known. Among important issues regarding this is its relation with heart diseases. Based on studies this comorbidity increase morbidity and mortality and leads to worst prognosis. However the cause of such high rate of comorbidity is unclear and instead of efforts to understand this correlation has prompted the medical world to consult other medicinal disciplines, not only to find the answer but also to increase the effectiveness of treatment and decrease its cost. Methods: We first reviewed the most important ancient causes for depression mentioned by Avicenna and considered those as the key words for our next step. Then, we made a literature search (PubMed and Scopus) with those key words to find out new scientific findings in modern medicine about the Avicenna's suggestions. Results: Avicenna does not regard depression as only a mental ailment, but as a disorder resulted by the involvement of brain, heart and blood. He believed that the main causes of depressive events are rooted in heart diseases; in most cases brain is only affected secondary to the heart. Thus he declared that for the treatment of depressive disorders, the underlying cardiovascular diseases should be considered. Conclusions: It is worthwhile to consider the Avicenna's recommended causes of depression and to design future scientific studies based on his suggestions.

  11. Droplet Freezing by Surface Nucleation

    Microsoft Academic Search

    Narayan R. Gokhale; James Goold Jr.

    1968-01-01

    Droplet freezing by surface nucleation has been observed during the course of studies of ice nucleation in our laboratories. A constant rate of cooling apparatus and a specially constructed cold chamber were used for this study. Silver iodide particles sprinkled on supercooled, millimeter-size water drops are effective in freezing the drops at 5C. Particles of naturally occurring silicates were found

  12. Preparation of soil specimens for SEM analysis using freeze-cut-drying

    Microsoft Academic Search

    B. Shi; Z. Wu; H. Inyang; J. Chen; B. Wang

    1999-01-01

    A new method, freeze-cut-drying, is introduced for preparing a soil specimen for microstructural analysis using scanning\\u000a electron microscopy (SEM). With this method, moisture in the specimen is removed by freeze-drying and an SEM observation surface\\u000a is made by cutting the specimen at a temperature below freezing point. Tests on bentonite clay were used to compare the results\\u000a from this method

  13. Thermal freeze-out versus chemical freeze-out reexamined

    E-print Network

    Dariusz Prorok

    2010-03-04

    An alternative, to the commonly used blast-wave, model describing the freeze-out hypersurface is applied to fit the $p_{T}$-spectra of identified hadrons measured at relativistic heavy-ion collisions at $\\sqrt{s_{NN}}=62.4, 130$ and 200 GeV. Decays of resonances are taken into account completely. It has turned out that the fitted freeze-out temperature and baryon number chemical potential depend weakly on the centrality of the collision and their values are close to the chemical freeze-out values determined from fits to particle yield ratios.

  14. Benchmarking numerical freeze/thaw models

    NASA Astrophysics Data System (ADS)

    Rühaak, Wolfram; Anbergen, Hauke; Molson, John; Grenier, Christophe; Sass, Ingo

    2015-04-01

    The modeling of freezing and thawing of water in porous media is of increasing interest, and for which very different application areas exist. For instance, the modeling of permafrost regression with respect to climate change issues is one area, while others include geotechnical applications in tunneling and for borehole heat exchangers which operate at temperatures below the freezing point. The modeling of these processes requires the solution of a coupled non-linear system of partial differential equations for flow and heat transport in space and time. Different code implementations have been developed in the past. Analytical solutions exist only for simple cases. Consequently, an interest has arisen in benchmarking different codes with analytical solutions, experiments and purely numerical results, similar to the long-standing DECOVALEX and the more recent "Geothermal Code Comparison" activities. The name for this freezing/ thawing benchmark consortium is INTERFROST. In addition to the well-known so-called Lunardini solution for a 1D case (case T1), two different 2D problems will be presented, one which represents melting of a frozen inclusion (case TH2) and another which represents the growth or thaw of permafrost around a talik (case TH3). These talik regions are important for controlling groundwater movement within a mainly frozen ground. First results of the different benchmark results will be shown and discussed.

  15. A Model for Prediction of Shrinkage Defects in Long and Short Freezing Range Materials

    SciTech Connect

    Reis, A.; Duarte, J. F.; Santos, A. D.; Magalhaes, A. B. [FEUP - Faculdade de Engenharia da Universidade do Porto, R.Dr.Roberto Frias s/n, 4200-110 Porto (Portugal); Xu Zhian [WTCM Foundry Center, Research Center of Belgium Metalworking Industry9052 Zwijnaarde, Gent (Belgium); Houbaert, Y. [UGent - University of Ghent, Technologiepark Zwijnaarde 903, Gent (Belgium)

    2007-05-17

    The aim of the model presented in this paper is to capture the difference in solidification behaviour of long and short freezing materials. The shrinkage defects in short freezing materials tends to be internal, as porosity, while in long freezing materials these defects tend to be external in the form of surface depressions. To achieve this, a pressure drop based 3-D feeding flow model has been developed to evaluate shrinkage defects for casting alloys. A continuum formulation is used to describe the transport of mass, energy and momentum. It is assumed that during solidification the driving force for flow is shrinkage. A Darcy type source term has been included in the momentum equation to account for flow resistance in the mushy zone. A VOF free surface model has been used to describe shrinkage defects, i.e., external surface depressions and internal shrinkage porosities, while ensuring mass conservation. The model is used to calculate the shrinkage in a simple casting. The results shows internal and outside shrinkage defects depending on the freezing range of the metal. Short freezing range results mainly in internal shrinkage whereas the long freezing range results in external shrinkage. The expected shrinkage features are well described by the present model.

  16. Commercial Application of Freeze Crystallization 

    E-print Network

    Gorgol, R. G.

    1992-01-01

    crystallization, low temperature operation, separation of organic and in-organic contaminants, can be put to use. Freeze crystallization can be applied both economically and practically for specific wastewater applications....

  17. Geriatric Depression in Primary Care

    PubMed Central

    Park, Mijung; Unützer, Jürgen

    2011-01-01

    Primary care settings present important opportunities for the detection and management of depression in older adults. As many as 10 % of older adults presenting in primary care have clinically significant depression, but only about half are recognized and only one in five depressed older adults receive effective treatment in primary care. We review common barriers to effective treatment such as atypical clinical presentations and comorbid medical conditions that are common in older adults. We identify treatment strategies such as measurement-based stepped care and collaborative care that can substantially improve the effectiveness of treatment in this setting and we highlight opportunities for addressing health disparities in geriatric depression care. We also point out the importance of engaging and supporting family caregivers of depressed older adults. We conclude by identifying three strategic areas to improve the treatment of geriatric depression in primary care: activation and engagement of patients and family members, health care provider training, and broader system changes. PMID:21536169

  18. Heritage roundtable: the nuclear freeze

    SciTech Connect

    Allen, R.V.; Gray, C.; Kalicki, J.; Pfaltzgraff, R.; Scoville, H.

    1982-01-01

    The transcript of a panel of foreign policy experts, chaired by former National Security Adviser Richard Allen, debates the proposed nuclear freeze. They consider whether a freeze is a step in the right direction, acting to slow the arms race and contribute to world security, or whether it would aggravate strategic problems by perpetuating an umbalanced situation. Disagreement among the participants makes clear that no one favors nuclear war, but there are differing perspectives on how to continue preventing such a war.

  19. Freezing behaviour of microencapsulated water.

    PubMed

    Yamane, H; Ohshima, H; Kondo, T

    1992-01-01

    The freezing behaviour of water in polyurea microcapsules was studied through DSC (differential scanning calorimetry) and ESR (electron spin resonance) measurements under a non-equilibrium condition to show that supercooling of water becomes more noticeable with decreasing droplet size of the liquid. Thermodynamics of small systems was found applicable to analyse the experimental findings, even though the process of water freezing in the microcapsules was not of an equilibrium nature. PMID:1328582

  20. Novel Real-Time Diagnosis of the Freezing Process Using an Ultrasonic Transducer

    PubMed Central

    Tseng, Yen-Hsiang; Cheng, Chin-Chi; Cheng, Hong-Ping; Lee, Dasheng

    2015-01-01

    The freezing stage governs several critical parameters of the freeze drying process and the quality of the resulting lyophilized products. This paper presents an integrated ultrasonic transducer (UT) in a stainless steel bottle and its application to real-time diagnostics of the water freezing process. The sensor was directly deposited onto the stainless steel bottle using a sol-gel spray technique. It could operate at temperature range from ?100 to 400 °C and uses an ultrasonic pulse-echo technique. The progression of the freezing process, including water-in, freezing point and final phase change of water, were all clearly observed using ultrasound. The ultrasonic signals could indicate the three stages of the freezing process and evaluate the cooling and freezing periods under various processing conditions. The temperature was also adopted for evaluating the cooling and freezing periods. These periods increased with water volume and decreased with shelf temperature (i.e., speed of freezing). This study demonstrates the effectiveness of the ultrasonic sensor and technology for diagnosing and optimizing the process of water freezing to save energy. PMID:25946629

  1. Ultrasonic Measurements of Unconsolidated Saline Sediments During Freeze/Thaw Cycles: The Seismic Properties of Cryopeg Environments

    NASA Astrophysics Data System (ADS)

    Dou, S.; Ajo Franklin, J. B.

    2013-12-01

    Saline permafrost and cryopegs (hypersaline unfrozen layers/zones within permafrost) are widespread in the Arctic coastal area as a result of marine transgression and regression in recent geological history. Owing to the freezing-point depression effect of soluble salts, they contain more unfrozen water than non-saline frozen sediments when subjected to the same permafrost temperatures (e.g., from 0 to -15 °C). Mapping subsurface cryopeg structure remains a challenging geophysical task due to the poor penetration of GPR in highly conductive fluids and related limitations for lower frequency EM techniques. Seismic profiling, particularly surface wave characterization, provides one possible approach to delineate the extent of cryopeg bodies. However, interpretation of such surveys is currently limited by the sparse database of measurements examining the seismic properties of unconsolidated materials saturated with saline fluids at sub-zero temperatures. We present the results of experiments examining seismic velocity in the ultrasonic range for both synthetic and natural permafrost sediments during freeze/thaw cycles; in these experiments, use of a range of brine salinities allows us to evaluate the properties of cryopeg sediments at in-situ conditions, a prerequisite for quantitative interpretation of seismic imaging results. Because of the abundant unfrozen water and less developed inter-granular ice structure, the seismic properties of saline permafrost typically falls between frozen and unfrozen soils. We conducted ultrasonic measurements of a freeze-thaw cycle on 20-30 Ottawa sand (grain size 590-840 ?m) as well as natural mineral soils from the Barrow Environmental Observatory (BEO) saturated with brines of different salinities (0-2.5 M NaCl). For each salinity, seismic properties were measured using the ultrasonic (~1 MHz) pulse-transmission method in the temperature range from 20 to -30 °C. Similar to sediments saturated with low salinity fluids, seismic velocities increase significantly upon freezing in brine-saturated samples due to the formation of ice. However, substantial differences were observed: First, the onset of the velocity increase occurred at temperatures significantly below 0 °C (e.g., as low as -11.8 °C for 2.5 M pore-water salinity); Second, instead of having a stepwise velocity increase (temperature derivative of velocity on the order of 1000 m/s/°C) in the immediate neighborhood of the freezing-point as in non-saline samples, velocities in saline samples exhibit a gradual increase (dv/dT as low as ~70 m/s/°C) in temperatures between the freezing-point and the eutectic-point (~-25 °C) of NaCl solutions. Unusual increases in attenuation were also observed in the vicinity of freezing. Our results indicate that saline permafrost and cryopegs have distinct seismic properties when compared with their non-saline counterparts under the same thermal conditions. Moreover, the very low seismic velocities observed in this laboratory study are consistent with the low-velocity zones at Barrow, Alaska that were previously found through field-scale geophysical investigations.

  2. An improved microscope stage for direct observation of freezing and freeze drying.

    PubMed

    Nail, S L; Her, L M; Proffitt, C P; Nail, L L

    1994-08-01

    A microscope stage for observation of freezing and freeze drying is described. The stage uses thermoelectric (Peltier) heaters configured in two stages, with circulating fluid as a heat sink on the high temperature side. Lowest attainable sample temperature is about -47 degrees C. Principal advantages of this system are closed-loop control of stage temperature, rapid response to changes in temperature set point, and improved documentation of experiments by use of a video recorder system with a character generator which allows display of sample identity and temperature. Accuracy of measuring the sample temperature in the field of view was validated by comparing observed values of eutectic melting with published values for a series of solutes with eutectic temperatures in the range from -2 degrees C to -32 degrees C. Good agreement was obtained throughout this range. PMID:7971708

  3. Synchrotron X-Ray Visualisation of Ice Formation in Insects during Lethal and Non-Lethal Freezing

    PubMed Central

    Sinclair, Brent J.; Gibbs, Allen G.; Lee, Wah-Keat; Rajamohan, Arun; Roberts, Stephen P.; Socha, John J.

    2009-01-01

    Although the biochemical correlates of freeze tolerance in insects are becoming well-known, the process of ice formation in vivo is subject to speculation. We used synchrotron x-rays to directly visualise real-time ice formation at 3.3 Hz in intact insects. We observed freezing in diapausing 3rd instar larvae of Chymomyza amoena (Diptera: Drosophilidae), which survive freezing if it occurs above ?14°C, and non-diapausing 3rd instar larvae of C. amoena and Drosophila melanogaster (Diptera: Drosophilidae), neither of which survive freezing. Freezing was readily observed in all larvae, and on one occasion the gut was seen to freeze separately from the haemocoel. There were no apparent qualitative differences in ice formation between freeze tolerant and non-freeze tolerant larvae. The time to complete freezing was positively related to temperature of nucleation (supercooling point, SCP), and SCP declined with decreasing body size, although this relationship was less strong in diapausing C. amoena. Nucleation generally occurred at a contact point with the thermocouple or chamber wall in non-diapausing larvae, but at random in diapausing larvae, suggesting that the latter have some control over ice nucleation. There were no apparent differences between freeze tolerant and non-freeze tolerant larvae in tracheal displacement or distension of the body during freezing, although there was markedly more distension in D. melanogaster than in C. amoena regardless of diapause state. We conclude that although control of ice nucleation appears to be important in freeze tolerant individuals, the physical ice formation process itself does not differ among larvae that can and cannot survive freezing. This suggests that a focus on cellular and biochemical mechanisms is appropriate and may reveal the primary adaptations allowing freeze tolerance in insects. PMID:20011523

  4. ANNAGNPS: ACCOUNTING FOR SNOWPACK, SNOWMELT, FREEZING AND THAWING OF SOIL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The watershed model, AnnAGNPS (Annualized AGricultural Non-Point Source Pollution model) has been enhanced by incorporating winter climate algorithms that account for frozen soil conditions. The model includes snowpack accumulation and melt, and the freeze/thaw process in the soil. Three major imp...

  5. Endocytotic activity of kitten odontoblasts in early dentinogenesis. 1. Thin section and freeze-fracture study.

    PubMed Central

    Sasaki, T; Tominaga, H; Higashi, S

    1984-01-01

    The morphological features of odontoblast processes in young kitten odontoblasts were studied by thin section and freeze-fracture electron microscopy. Freeze-fracture replication revealed depressions with particles on the plasma membranes of the proximal parts of odontoblast processes. Comparison with thin sections suggested that these depressions represented sites of endocytosis. Frequent depressions with particles (corresponding to coated pits in thin sections) indicate the high absorptive activity of young odontoblasts. The results indicate that odontoblasts, especially in the proximal parts of their processes, play a significant functional role in the modification of the predentine matrix during early dentinogenesis. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:6735910

  6. Major depression.

    PubMed

    Bentley, Susan M; Pagalilauan, Genevieve L; Simpson, Scott A

    2014-09-01

    Major depression is a common, disabling condition seen frequently in primary care practices. Non-psychiatrist ambulatory providers are increasingly responsible for diagnosing, and primarily managing patients suffering from major depressive disorder (MDD). The goal of this review is to help primary care providers to understand the natural history of MDD, identify practical tools for screening, and a thoughtful approach to management. Clinically challenging topics like co-morbid conditions, treatment resistant depression and pharmacotherapy selection with consideration to side effects and medication interactions, are also covered. PMID:25134869

  7. The effects of freezing and thawing on the aqueous availability of creosote contamination in soil

    SciTech Connect

    Bevel, A.; Hrudey, S.; Dudas, M.; Sego, D. [Univ. of Alberta, Edmonton, Alberta (Canada)

    1996-11-01

    A variety of methods have been tested in attempts to remediate contaminated sites. Fine-grained soils are extremely problematic to remediate, due to the high adsorption capacity of the fine soil particles and the trapping effect of soil particle micropores. It is well documented that freezing of soil causes particle restructuring and reorganization, with different pore structures found after freezing. Some factors affecting restructuring include soil moisture content, freezing rate, freezing end-point temperature, and number of freezing cycles. This poster presents an experiment that determines if freezing creosote contaminated soil improves accessibility of the creosote, by measuring aqueous phase contaminant dissolution. This method was selected since water is the most common solvent in naturally occurring systems, and water represents a worst-case scenario since many contaminants have low aqueous solubilities. Freezing is carried out under controlled laboratory conditions. Variables examined include moisture content, freezing rate, and soil contamination level. If contaminant availability is increased through soil freezing, remediation becomes an easier task in fine grained soils.

  8. Mechanism of freeze-thaw instability of aluminum hydroxycarbonate and magnesium hydroxide gels.

    PubMed

    Zapata, M I; Feldkamp, J R; Peck, G E; White, J L; Hem, S L

    1984-01-01

    The effect of freeze-thaw cycles on the physical stability of aluminum hydroxycarbonate and magnesium hydroxide gels was studied. Coagulation following a freeze-thaw cycle, leading to the formation of visible aggregates, affected the content uniformity of both gels. The freeze-thaw cycles did not affect the crystal form or surface characteristics of the gels as determined by X-ray powder diffraction and point of zero charge, but caused a slight reduction in the rate of acid neutralization and a large increase in the rate of sedimentation. The greatest effect was observed after the first freeze-thaw cycle. While the duration of freezing was not a factor, the rate of freezing was important and was inversely related to the aggregate size. The aggregates which formed following a freeze-thaw cycle were not redispersed by shaking, but were reversed by ultrasonic treatment or homogenization. The adsorption of polymers or surface-active agents prior to freezing reduced and, in some cases, prevented the formation of aggregates. The physical instability produced by a freeze-thaw cycle was explained by the modified DLVO theory. The force exerted on the particles by the growing ice crystals forced the particles into the primary minimum, producing strong interparticle attraction. On thawing, simple agitation did not provide enough force to overcome the attractive force of the primary minimum. Adsorption of polymers or surface-active agents increased the steric repulsive force and prevented the particles from reaching the primary minimum. PMID:6694078

  9. Non-Toxic, Low-Freezing, Drop-In Replacement Heat Transfer Fluids

    NASA Technical Reports Server (NTRS)

    Cutbirth, J. Michael

    2012-01-01

    A non-toxic, non-flammable, low-freezing heat transfer fluid is being developed for drop-in replacement within current and future heat transfer loops currently using water or alcohol-based coolants. Numerous water-soluble compounds were down-selected and screened for toxicological, physical, chemical, compatibility, thermodynamic, and heat transfer properties. Two fluids were developed, one with a freezing point near 0 C, and one with a suppressed freezing point. Both fluids contain an additive package to improve material compatibility and microbial resistance. The optimized sub-zero solution had a freezing point of 30 C, and a freezing volume expansion of 10-percent of water. The toxicity of the solutions was experimentally determined as LD(50) greater than 5g/kg. The solutions were found to produce minimal corrosion with materials identified by NASA as potentially existing in secondary cooling loops. Thermal/hydrodynamic performance exceeded that of glycol-based fluids with comparable freezing points for temperatures Tf greater than 20 C. The additive package was demonstrated as a buffering agent to compensate for CO2 absorption, and to prevent microbial growth. The optimized solutions were determined to have physically/chemically stable shelf lives for freeze/thaw cycles and longterm test loop tests.

  10. Freeze Protection for Gasholders ESGI64 Freeze Protection in Gasholders

    E-print Network

    Purvis, Richard

    and National Grid wishes to inves- tigate whether circulation of the tank water without external heating could of "tank water" at the base which is below ground. At present freeze- protection is achieved by external capacity and National Grid wishes to investi- gate whether circulation of the tank water without external

  11. The role and clinical significance of subsyndromal depressive symptoms (SSD) in unipolar major depressive disorder

    Microsoft Academic Search

    Lewis L Judd; Hagop S Akiskal; Martin P Paulus

    1997-01-01

    Analyses conducted in 10?526 community respondents investigated by the NIMH Epidemiological Catchment Area (ECA) Program, revealed the 1-month point prevalence of depressive symptoms and disorders in the general population, at the first ECA interview (Wave 1) to be 10%, as follows: 2.3% major depressive disorder (MDD); 2.3% dysthymic disorder (DD); 1.5% minor depressive disorder (MinD); and 3.9% subsyndromal depressive symptoms

  12. Freeze Crystallization Processes: Efficiency by Flexibility

    E-print Network

    Heist, J. A.; Barron, T. S.

    1983-01-01

    the entropy of the separation is less. 3) A heat pump is used in the freeze crystallization process to transfer heat from the freezer to the melter, providing advantages similar to the vapor compression evaporator cycle. Freeze crystallization should...

  13. 9 CFR 590.536 - Freezing operations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...590.536 Freezing operations. (a) Freezing rooms shall be kept clean and free from objectionable odors. (b) Requirements...d) The outside of liquid egg containers shall be clean and free from evidence of liquid egg. (e)...

  14. 9 CFR 590.536 - Freezing operations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...590.536 Freezing operations. (a) Freezing rooms shall be kept clean and free from objectionable odors. (b) Requirements...d) The outside of liquid egg containers shall be clean and free from evidence of liquid egg. (e)...

  15. 9 CFR 590.536 - Freezing operations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...590.536 Freezing operations. (a) Freezing rooms shall be kept clean and free from objectionable odors. (b) Requirements...d) The outside of liquid egg containers shall be clean and free from evidence of liquid egg. (e)...

  16. 9 CFR 590.536 - Freezing operations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...590.536 Freezing operations. (a) Freezing rooms shall be kept clean and free from objectionable odors. (b) Requirements...d) The outside of liquid egg containers shall be clean and free from evidence of liquid egg. (e)...

  17. 9 CFR 590.536 - Freezing operations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...590.536 Freezing operations. (a) Freezing rooms shall be kept clean and free from objectionable odors. (b) Requirements...d) The outside of liquid egg containers shall be clean and free from evidence of liquid egg. (e)...

  18. Status of Chemical Freeze-Out

    E-print Network

    J. Cleymans; H. Oeschler; K. Redlich; S. Wheaton

    2006-07-14

    The status of the energy dependence of the chemical freeze-out temperature and chemical potential obtained in heavy ion collisions is presented. Recent proposals for chemical freeze-out conditions are compared.

  19. Inbreeding depression and heterosis : Expected means and variances among inbred lines

    E-print Network

    Paris-Sud XI, Université de

    Inbreeding depression and heterosis : Expected means and variances among inbred lines depression are investigated from a theoretical point of view in an experiment involving several inbred lines depression phenomena ! Many experiments led to the definition of the relations hipbetweentheincrease

  20. Combined infrared and freeze-drying.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The drying of the combined infrared (IR) and freeze-drying of food materials has been shown to be very rapid compared to regular freeze drying (FD). The resulting tissue structure of products processed with sequential infrared and freeze drying (SIRFD) tends to have higher crispness than those proce...

  1. TISSUE FREEZING METHODS FOR CRYOSTAT SECTIONING

    E-print Network

    Chisholm, Rex L.

    TISSUE FREEZING METHODS FOR CRYOSTAT SECTIONING Basic Tissue Freezing Methods Preparing Tissue-Roll Plate; Speaker: Donna J. Emge, HT-ASCP, MHPL Manager #12;Preparing Tissue For Freezing Tissue morphological distortions and damage due to: · Tissue drying artifact. · Autolysis - The destruction of tissues

  2. Improvement of Freezing Quality of Food by Pre-dehydration with Microwave-Vacuum Drying

    NASA Astrophysics Data System (ADS)

    Hamidi, Nurkholis; Tsuruta, Takaharu

    Partial dehydration by microwave vacuum drying has been applied to tuna, oyster and mackerel prior to freezing in order to reduce quality damages due to freezing and thawing. Samples were dehydrated at pressure of 4kPa and temperature lower than 25°C. Two cooling conditions were tested in the experiment by using the freezing chamber of temperatures -20°C and -80°C. The experimental results showed that decreasing the water content in tuna could lower the freezing point temperature and made the freezing time shorter. It was also found that removing some water was effective to reduce the size of ice crystal and the drip loss in mackerel. After thawing, the pre-dehydrated mackerel showed better microstructure than that frozen without pre-treatment. Furthermore, the sensory tests have been done by a group of panelist for the evaluation on aroma, flavor, and general acceptability of mackerels.

  3. Preparation of porous scaffolds by using freeze-extraction and freeze-gelation methods

    Microsoft Academic Search

    Ming-Hua Ho; Pei-Yun Kuo; Hsyue-Jen Hsieh; Tzu-Yang Hsien; Lein-Tuan Hou; Juin-Yih Lai; Da-Ming Wang

    2004-01-01

    Freeze-fixation and freeze-gelation methods are presented in this paper which can be used to prepare highly porous scaffolds without using the time and energy consuming freeze-drying process. The porous structure was generated during the freeze of a polymer solution, following which either the solvent was extracted by a non-solvent or the polymer was gelled under the freezing condition; thus, the

  4. Depression in Older Adults

    MedlinePLUS

    ... Depression In Older Adults: More Facts Depression In Older Adults: More Facts Depression affects more than 19 million ... medication, psychotherapy or a combination of both. [8] Older Adult Attitudes Toward Depression: According to a Mental Health ...

  5. Depression and Pregnancy

    MedlinePLUS

    Depression and Pregnancy This sheet talks about the risks of depression during pregnancy. With each pregnancy, all women have a 3% ... is depression and how common is it in pregnancy? Depression is a serious medical illness that has ...

  6. The effects of IL2Rgamma knockout on depression and contextual memory.

    PubMed

    Wu, Xiaojun; Kastin, Abba J; Hsuchou, Hung; Pan, Weihong

    2010-12-01

    Interleukin (IL)-2Rgamma shows robust upregulation in neuroinflammatory states associated with clinical depression. We tested the hypothesis that mice lacking IL2Rgamma would have decreased depressive-like behavior. Contrary to this expectation, these knockout mice showed increased immobility in both the Porsolt forced swimming and Nomura water wheel tests. By comparison, the auditory fear conditioning test showed increased retention of contextual freezing. Thus, intact IL2Rgamma combats depressive-like behavior. PMID:20438766

  7. The effects of IL2R? knockout on depression and contextual memory

    PubMed Central

    Wu, Xiaojun; Kastin, Abba J.; Hsuchou, Hung; Pan, Weihong

    2010-01-01

    Interleukin (IL)-2R? shows robust upregulation in neuroinflammatory states associated with clinical depression. We tested the hypothesis that mice lacking IL2R? would have decreased depressive-like behavior. Contrary to this expectation, these knockout mice showed increased immobility in both the Porsolt forced swimming and Nomura water wheel tests. By comparison, the auditory fear conditioning test showed increased retention of contextual freezing. Thus, intact IL2R? combats depressive-like behavior. PMID:20438766

  8. Freeze Technology for Nuclear Applications - 13590

    SciTech Connect

    Rostmark, Susanne C.; Knutsson, Sven [Lulea University of Technology (Sweden)] [Lulea University of Technology (Sweden); Lindberg, Maria [Studsvik Nuclear AB, 611 82 Nykoeping (Sweden)] [Studsvik Nuclear AB, 611 82 Nykoeping (Sweden)

    2013-07-01

    Freezing of soil materials is a complicated process of a number of physical processes: - freezing of pore water in a thermal gradient, - cryogenic suction causing water migration and - ice formation expanding pores inducing frost heave. Structural changes due to increase of effective stress during freezing also take place. The over consolidation gives a powerful dewatering/drying effect and the freeze process causes separation of contaminates. Artificial ground freezing (AGF is a well established technique first practiced in south Wales, as early as 1862. AGF is mostly used to stabilize tunnels and excavations. During the last ten years underwater applications of freeze technologies based on the AGF have been explored in Sweden. The technology can, and has been, used in many different steps in a remediation action. Freeze Sampling where undisturbed samples are removed in both soft and hard sediment/sludge, Freeze Dredging; retrieval of sediment with good precision and minimal redistribution, and Freeze Drying; volume reduction of contaminated sludge/sediment. The application of these technologies in a nuclear or radioactive environment provides several advantages. Sampling by freezing gives for example an advantage of an undisturbed sample taken at a specified depth, salvaging objects by freezing or removal of sludges is other applications of this, for the nuclear industry, novel technology. (authors)

  9. Towards a scientific taxonomy of depression

    PubMed Central

    K. Ranga, Rama Krishnan

    Many concepts have been introduced into the classification of depression, including manic-depressive/bipolar disorder depression, etc. Kraepelin's original concept of manic-depressive disorder has evolved into the concept of polarity, and bipolar and unipolar disorders. Psychiatric classification is characterized by an inflation of the diagnostic categories, including subtypes of depression. This rapid multiplier effect is primarily descriptive, and there is a need to rethink, in a pragmatic fashion, the classification system, in order to develop one that is likely to be of utility and which has a scientific basis. Is the time now right to ask whether there are essential conditions relevant to depression? I think that it is, and here I will introduce the notion with two such conditions. The first is early life stress disorder, and the second vascular depression. These conditions have reached a point where the data supports them as distinct entities. In this paper, the rationale for this is discussed. PMID:18979943

  10. Depression - overview

    MedlinePLUS

    ... all ages: Adults Teenagers Older adults Symptoms of depression include: Low mood or irritable mood most of the time Trouble sleeping or sleeping too much A big change in appetite, often with weight gain or loss Tiredness and lack of energy Feelings ...

  11. Prenatal Paternal Depression

    PubMed Central

    Field, Tiffany; Diego, Miguel; Hernandez-Reif, Maria; Figueiredo, Barbara; Deeds, Osvelia; Contogeorgos, Jennifer; Ascencio, Angela

    2007-01-01

    Prenatal depressive symptoms, anxiety, anger and daily hassles were investigated in 156 depressed and non-depressed pregnant women and their depressed and non-depressed partners (fathers-to-be). Depressed versus non-depressed fathers had higher depression, anxiety and daily hassles scores. Although the pregnant women in general had lower anxiety, anger and daily hassles scores than the men, the scores on the measures for depressed fathers and depressed mothers did not differ. Paternal depression appeared to have less effect than maternal depression on their partners’ scores. However, the similarity between the scores of depressed mothers and depressed fathers highlights the importance of screening for depression in fathers-to-be as well as mothers-to-be as well as during pregnancy. PMID:17138311

  12. Commercial Application of Freeze Crystallization

    E-print Network

    Gorgol, R. G.

    begun to realize water is a very valuable resource. Even municipalities must husband thcir water. The day is coming very soon when all industrywill produce clean water as a cash product and water use will be carefully managed. Everywhere you look... becn since the world bcgan. The most noticeable frozen substance is, of course, water. Snow, ice cubcs, frozen lakes and streams, even iccbcrgs are all evidences of the freezing process at work. This process is also used to form crystalline...

  13. Freezing Poultry for Home Use

    E-print Network

    Davis, Michael

    2006-08-31

    . ? As you work, keep the cutting surface and utensils clean. ? Work quickly and place the poultry in the freezer as quickly as possible. ? Do not let raw poultry juices contaminate ready-to-eat foods. Answering the following questions will help you decide... airtight packaging when freezing poultry. Airtight packaging prevents dehydration and freezer burn. It also helps prevent fat rancidity, oxidation, spoilage, and the growth of disease-causing bacteria. Shrink packages, like the bags in which frozen...

  14. Additional weight load increases freezing of gait episodes in Parkinson's disease; an experimental study.

    PubMed

    Mensink, Senja H G; Nonnekes, Jorik; van Bon, Geert; Snijders, Anke H; Duysens, Jacques; Weerdesteyn, Vivian; Bloem, Bastiaan R; Oude Nijhuis, Lars B

    2014-05-01

    Freezing of gait is an episodic gait disorder,characterized by the inability to generate effective forward stepping movements. The pathophysiology underlying freezing of gait remains insufficiently understood, and this hampers the development of better treatment strategies.Preliminary evidence suggests that impaired force control during walking may contribute to freezing episodes, with difficulty to unload the swing leg and initiate the swing phase. Here, we used external loading to manipulate force control and to investigate its influence on freezing of gait.Twelve Parkinson's disease patients with freezing of gait performed three contrasting tasks: (1) loaded gait while wearing a belt fortified with lead weights; (2) weight supported gait using a parachute harness connected to a rigid metal cable running above the gait trajectory; and (3)normal gait. Gait tasks were used to provoke freezing episodes, including rapid 360° turns. Freezing episodes were quantified using blinded, videotaped clinical assessment. Furthermore, ground reaction forces and body kinematics were recorded. Loading significantly increased the mean number of freezing episodes per trial compared to the normal gait condition (P<0.05), but the effect of weight support was not consistent. Loading particularly increased the number of freezing episodes during rapid short steps. Step length was significantly smaller during loaded gait compared to normal gait (P<0.05), but changes in anticipatory postural adjustments were not different.Our results may point to impaired force control playing a key role in freezing of gait. Future studies should further investigate the mechanism, i.e., the contribution of deficient load feedback, and evaluate which forms of weight support might offer treatment opportunities. PMID:24658705

  15. Development and design of sludge freezing beds

    SciTech Connect

    Martel, C.J.

    1987-01-01

    The purpose of this study was to develop design criteria for a new sludge dewatering unit operation called a sludge freezing bed. This bed uses natural freeze-thaw to condition the sludge for dewatering. The total depth of sludge which can be frozen, thawed and dewatered by this process in a year is the main criterion needed for design. The essential features of a freezing bed which would optimize natural freeze-thaw were identified through a literature review and site visits. Several laboratory tests were conducted to assess the dewaterability of freeze-thaw conditioned sludge at various depths. Water treatment plant sludge and both anaerobically and aerobically digested wastewater sludges were used in these tests. Mathematical models for predicting the design depth were developed and validated with data from other sludge freezing operations. Values for the input parameters to the models were obtained from the literature or from laboratory and pilot-scale experiments.

  16. Freeze-Drying Characteristics of Tropical Fruits

    Microsoft Academic Search

    Ana M. Silveira; José T. Freire

    2006-01-01

    The objective of this work was to experimentally determine physical properties such as apparent densities, real densities, and porosity of freeze-dried tropical fruits pulps such as pineapple, Barbados cherry, guava, papaya, and mango, and to carry out nutritional analysis of vitamin C, calcium, and phosphorus in the freeze-dried and in natura pulps. The freeze-dried pulps presented low apparent density and

  17. Fundamental Technical Elements of Freeze-fracture/Freeze-etch in Biological Electron Microscopy

    EPA Science Inventory

    Freeze-fracture/freeze-etch describes a process whereby specimens, typically biological or nanomaterial in nature, are frozen, fractured, and replicated to generate a carbon/platinum "cast" intended for examination by transmission electron microscopy. Specimens are subjected to u...

  18. Freeze Enhanced Halate Halide Reactions

    NASA Astrophysics Data System (ADS)

    Newberg, J. T.; Weaver, K.; Broderick, A.

    2014-12-01

    Relatively little is known about halate ion species (XO3-; X = I, Br, Cl) in atmospheric condensed phases. It was initial thought that iodate was a terminal stable species upon iodide oxidation. However, it is becoming increasingly recognized that reactions involving iodate can lead to reactive iodine, and this chemistry is accelerated under acidic conditions. The environmental concentrations and chemistry of bromate and chlorate are largely unexplored in environmental ices. We present results from a series of aqueous phase halate ion reactions with halides under acidic conditions, showing that the kinetics are strongly enhanced upon freezing. The products of these reactions are reactive halogens, which have important implications to marine boundary layer chemistry.

  19. Freeze out in narrow and wide layers

    E-print Network

    V. K. Magas; L. P. Csernai; E. Molnar

    2006-01-19

    The freeze out of particles from a layer of finite thickness is discussed in a phenomenological kinetic model. The proposed model, based on the Modified Boltzman Transport Equation, is Lorentz invariant and can be applied equally well for the freeze out layers with space-like and time-like normal vectors. It leads to non-equilibrated post freeze out distributions. The dependence of the resulting distribution on the thickness of the layer is presented and discussed for a space-like freeze out scenario.

  20. Reptile freeze tolerance: metabolism and gene expression.

    PubMed

    Storey, Kenneth B

    2006-02-01

    Terrestrially hibernating reptiles that live in seasonally cold climates need effective strategies of cold hardiness to survive the winter. Use of thermally buffered hibernacula is very important but when exposure to temperatures below 0 degrees C cannot be avoided, either freeze avoidance (supercooling) or freeze tolerance strategies can be employed, sometimes by the same species depending on environmental conditions. Several reptile species display ecologically relevant freeze tolerance, surviving for extended times with 50% or more of their total body water frozen. The use of colligative cryoprotectants by reptiles is poorly developed but metabolic and enzymatic adaptations providing anoxia tolerance and antioxidant defense are important aids to freezing survival. New studies using DNA array screening are examining the role of freeze-responsive gene expression. Three categories of freeze responsive genes have been identified from recent screenings of liver and heart from freeze-exposed (5h post-nucleation at -2.5 degrees C) hatchling painted turtles, Chrysemys picta marginata. These genes encode (a) proteins involved in iron binding, (b) enzymes of antioxidant defense, and (c) serine protease inhibitors. The same genes were up-regulated by anoxia exposure (4 h of N2 gas exposure at 5 degrees C) of the hatchlings which suggests that these defenses for freeze tolerance are aimed at counteracting the injurious effects of the ischemia imposed by plasma freezing. PMID:16321368

  1. Psychotic Depression and Mortality

    Microsoft Academic Search

    Meena Vythilingam; Joyce Chen; B. S. J. Douglas Bremner; Carolyn M. Mazure; Paul K. Maciejewski; Craig Nelson

    2003-01-01

    Objective: Major depressive disorder is associated with elevated mortality rates that increase with the severity of depression. The authors hypothesized that patients with psychotic depression would have higher mortality rates than patients with nonpsy- chotic depression. Method: Survival analytic techniques were used to compare the vital status of 61 patients with psychotic major depression with that of 59 patients with

  2. Nutritional Interventions in Depression and Perinatal Depression

    PubMed Central

    Rechenberg, Kaitlyn; Humphries, Debbie

    2013-01-01

    Depression is the leading cause of mental disability worldwide. Women who are depressed during pregnancy are at a higher risk for preterm delivery, preeclampsia, birth difficulties, and postpartum depression. The treatment of depression in conventional medicine has focused on physiological factors that lead to impaired neurotransmitter function and treatments to improve neurotransmitter function. Pharmaceutical substances pose risks for pregnant and lactating women, and lower risk options are preferred. Micronutrients, including certain B vitamins, folate, and docosahexaenoic acid (DHA), play a role in the synthesis and absorption of neurotransmitters. Experimental studies suggest that supplementation with specific micronutrients may alleviate depressive symptoms and improve birth outcomes in patients with perinatal depression. Alternative treatments for depression, including nutritional supplements, are an important treatment option for depressive symptoms while limiting potential side effects and treatment costs. This article explores the biological basis of perinatal depression and reviews the potential benefits of non-pharmacological interventions. PMID:23766734

  3. The GABAergic deficit hypothesis of major depressive disorder

    Microsoft Academic Search

    B Luscher; Q Shen; N Sahir

    2011-01-01

    Increasing evidence points to an association between major depressive disorders (MDDs) and diverse types of GABAergic deficits. In this review, we summarize clinical and preclinical evidence supporting a central and causal role of GABAergic deficits in the etiology of depressive disorders. Studies of depressed patients indicate that MDDs are accompanied by reduced brain concentration of the inhibitory neurotransmitter ?-aminobutyric acid

  4. Altered BDNF and Dopamine Levels In Depression

    NSDL National Science Digital Library

    2009-12-26

    Doctor Abraham Zangen point out that dopamine and BDNF levels in the nucleus accumbens and hippocampus of depressed patients are different. Treatment with antidepressants or ECT can impact these differences.

  5. Depression - older adults

    MedlinePLUS

    ... daily life for weeks or longer. Depression in older adults is a widespread problem, but it is not ... In older adults, life changes can increase the risk for depression or make existing depression worse. Some of these changes ...

  6. Depression and Diabetes

    MedlinePLUS

    ... see the NIMH booklet on Depression . What is diabetes? Diabetes is an illness that affects the way ... are starved of energy. How are depression and diabetes linked? Studies show that depression and diabetes may ...

  7. Deliquescence and freezing of stratospheric aerosol observed by balloonborne backscattersondes

    NASA Astrophysics Data System (ADS)

    Larsen, Niels; Rosen, James M.; Kjome, Norman T.; Knudsen, Bjorn

    1995-05-01

    Stratospheric sulfate aerosols, originating from the Mt. Pinatubo volcanic eruption, have been observed during three winters in the Arctic by balloonborne backscattersondes. A measured color index, defined as the quotient between the aerosol backscatter ratios at wavelengths 940 and 480 nm, provides information of the size of the observed particles. The effects of liquid particle growth, by water vapor uptake, clearly show up as changes in the color index, whereas measurements on other days indicate the particles to be frozen. Air parcel trajectories have been calculated, providing the temperature history of the observed particles. Evidences appear of a temperature hysteresis in the freezing and melting cycle of the aerosol, indicating melting temperatures around 215-220 K in good agreement with laboratory measurements, and freezing of the particles within less than 5 K above the ice frost point. The changes in color index of the liquid particles are in good agreement with predictions from theoretical model calculations of growth by water vapor uptake.

  8. Relationship of Product Structure, Sorption Characteristics, and Freezing Point of Atmospheric Freeze-Dried Foods

    Microsoft Academic Search

    Ingrid Camilla Claussen; Ingvald Strømmen; Anne Karin Torstveit Hemmingsen; Turid Rustad

    2007-01-01

    Drying is an important unit operation in processing of foods with a long shelf life. The drying process influences product properties and quality; the products may shrink, break, or undergo rheological, physical, and biochemical changes. Important parameters responsible for product quality changes during drying are temperature, relative humidity, and residence time. Studies of thermal and mass transfer properties during drying

  9. Is it possible to reconstruct the freeze-out duration of heavy-ion collisions using tomography?

    E-print Network

    David A. Brown

    2000-03-10

    We investigate what conditions allow us to extract the relative distribution of freeze-out space and time points in an arbitrary reference frame using tomography and source imaging. The source function may be extracted from the two-particle correlation function measured in heavy-ion collisions using imaging techniques. This imaged source function is related to the relative distribution of freeze-out space and time points through a generalization of the Radon transform found in tomography. Using tomography, the imaged source function may be converted into the relative freeze-out distribution in the frame of interest. We describe how the tomography may be performed in practice.

  10. Improving Forecasts of Freezing Rain at ECMWF

    NASA Astrophysics Data System (ADS)

    Tsonevsky, Ivan; Forbes, Richard; Hewson, Tim

    2015-04-01

    Freezing rain events, though relatively rare, can be extremely debilitating and dangerous for society, with recovery times of order months or even years. Analysis of forecasts of past events by the operational ECMWF Integrated Forecast System (IFS) showed a strong tendency to incorrectly represent freezing rain as snow. Investigations highlighted that this was primarily because the re-freezing process in IFS, following hydrometeors as they descend, was parametrised with the same time-scale as the melting process. In reality the time-scale for re-freezing should, in general, be much longer. The model physics were changed accordingly, and the results in terms of forecast quality were positive and very striking. Coupled with these physics changes new IFS output was developed for users which shows precipitation type at the surface (rain, snow, wet snow, sleet, freezing rain, ice pellets). The changes to the physics will be described in detail, and their impact will be illustrated by comparing forecast output for past events in new and old model versions, in terms of precipitation type and intensity. Illustrations will include short-range deterministic forecasts from 'HRES' (the high resolution ECMWF model), and longer range probabilistic forecasts of freezing rain occurrence from the ensemble. There will also be reference to issues requiring further work/investigation, such as high level convection in potential freezing rain cases, freezing drizzle generated in supercooled shallow clouds, and IFS retention of the 'warm nose' in which melting occurs.

  11. Modeling frost heave in freezing soils

    Microsoft Academic Search

    Leonid Bronfenbrener; Regina Bronfenbrener

    2010-01-01

    A generalized model for secondary frost heave in freezing fine-grained soils is presented. The cryostatic suction effect, which causes an increase in upward water permeation, ice-lens growth during freezing, and, as a consequence, the increase of soil heave, is considered to be the main mechanism of moisture transfer. Although the model in this paper has a number of approaches in

  12. Freezing: an underutilized food safety technology?

    PubMed

    Archer, Douglas L

    2004-01-15

    Freezing is an ancient technology for preserving foods. Freezing halts the activities of spoilage microorganisms in and on foods and can preserve some microorganisms for long periods of time. Frozen foods have an excellent overall safety record. The few outbreaks of food-borne illness associated with frozen foods indicate that some, but not all human pathogens are killed by commercial freezing processes. Freezing kills microorganisms by physical and chemical effects and possibly through induced genetic changes. Research is needed to better understand the physical and chemical interactions of various food matrices with the microbial cell during freezing and holding at frozen temperatures. The literature suggests that many pathogenic microorganisms may be sublethally injured by freezing, so research should be done to determine how to prevent injured cells from resuscitating and becoming infectious. Studies on the genetics of microbial stress suggest that the induction of resistance to specific stresses may be counteracted by, for example, simple chemicals. Research is needed to better understand how resistance to the lethal effect of freezing is induced in human pathogens and means by which it can be counteracted in specific foods. Through research, it seems possible that freezing may in the future be used to reliably reduce populations of food-borne pathogens as well as to preserve foods. PMID:14698095

  13. Depression, confidence, and decision Running head: DEPRESSION, CONFIDENCE, AND DECISION

    E-print Network

    Koutstaal, Wilma

    Depression, confidence, and decision -1- Running head: DEPRESSION, CONFIDENCE, AND DECISION Depression, confidence, and decision: Evidence against depressive realism Tiffany Fu, 1 Wilma Koutstaal, 1, 2;Depression, confidence, and decision -2- Abstract This research examined how retrospective self

  14. Microphysical Modelling of the 1999-2000 Arctic Winter. 3; Impact of Homogeneous Freezing on PSCs

    NASA Technical Reports Server (NTRS)

    Drdla, K.

    2003-01-01

    Simulations of the 1999-2000 winter have tested the effect on polar stratospheric clouds (PSCs) of the homogeneous freezing of liquid ternary solutions into nitric acid trihydrate (NAT) and nitric acid dihydrate (NAD). Proposed laboratory-derived volume-based and surface-based homogeneous freezing rates have both been examined, including different assumptions about the extrapolation of laboratory measurements to atmospheric conditions. Widespread PSC formation and denitrification are possible in several of the scenarios examined. However, the simulations are all unable to explain the solid-phase PSCs observed early in the 1999-2000 winter, and are unable to reproduce the measured extent of vortex denitrification. These problems can both be attributed to the relatively cold temperatures, more than 5 K below the NAT condensation point, necessary for effective homogeneous freezing. Therefore synoptic-scale homogeneous freezing appears unlikely to be the primary mechanism responsible for solid-phase PSC formation.

  15. Freeze-drying for morphological control of high performance semi-interpenetrating polymer networks. III

    NASA Technical Reports Server (NTRS)

    Hsiung, H. J.; Hansen, M. G.; Pater, R. H.

    1991-01-01

    The feasibility of using a freeze-drying (solvent removal by sublimation) approach for controlling the morphology of a high-performance semi-IPN is assessed. A high-performance thermoplastic polyimide and commercially available 4,4'-bismaleimide diphenylenemethane were dissolved in a solvent, 1,3,5-trioxane. The solvent was removed from the constituents by freeze-drying. For purposes of comparison, the constituents were dissolved in a high-boiling-point solvent, N,N-dimethylformamide. The solvent was removed from the solution by evaporation. The physical and mechanical properties and phase morphology of the neat resins and composites prepared by freeze-drying and traditional solution methods are presented and compared. It is concluded that the TG is higher and that the magnitude of minor constituent separation is less in the freeze-dry processed materials than for the processed solution.

  16. 7 CFR 305.7 - Quick freeze treatment requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Quick freeze treatment requirements. 305.7 Section 305.7...DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.7 Quick freeze treatment requirements. Quick freeze...

  17. 7 CFR 305.7 - Quick freeze treatment requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Quick freeze treatment requirements. 305.7 Section 305.7...DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.7 Quick freeze treatment requirements. Quick freeze...

  18. 7 CFR 305.7 - Quick freeze treatment requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Quick freeze treatment requirements. 305.7 Section 305.7...DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.7 Quick freeze treatment requirements. Quick freeze...

  19. 7 CFR 305.7 - Quick freeze treatment requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Quick freeze treatment requirements. 305.7 Section 305.7...DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS § 305.7 Quick freeze treatment requirements. Quick freeze...

  20. Depressive Symptoms After CABG Surgery: A Meta-analysis

    PubMed Central

    Ravven, Simha; Bader, Caroline; Azar, Armin; Rudolph, James L.

    2013-01-01

    Objective Depression is highly comorbid with coronary artery disease. Clinicians face the question of whether patients’ depressive symptoms will improve after coronary artery bypass graft surgery (CABG). The objective of this meta-analysis is to determine the course of depressive symptoms after CABG. Methods EMBASE, PubMed, and PsycINFO were searched for studies assessing depression before and after CABG. Meta-analyses were performed for depression at early (1–2 weeks), recovery (>2 weeks to 2 months), mid (>2 months to 6 months), and late (>6 months) postoperative time points. Heterogeneity and publication bias were analyzed. Results Thirty-nine studies were included in the meta-analysis. Twelve reported dichotomous outcomes; 18 reported continuous outcomes; and 9 reported both. Risk of depression was increased early (relative risk [RR] = 1.27; 95% confidence interval [CI], 1.01–1.61). There was a significantly decreased risk of depression at recovery (RR = 0.78; 95% CI, 0.67–0.90), mid (RR = 0.64; 95% CI, 0.58–0.70), and late (RR = 0.68; 95% CI, 0.58–0.79) time points without heterogeneity. All studies reporting continuous depression scales had significant heterogeneity. Conclusions The risk of depression decreased post-CABG when depression was measured dichotomously. While depression improves overall and remits for some patients after CABG, the majority of patients will not experience remission of depression. Preoperative and postoperative depression monitoring is important. PMID:23656830

  1. Learning and memory impairments in a neuroendocrine mouse model of anxiety/depression

    PubMed Central

    Darcet, Flavie; Mendez-David, Indira; Tritschler, Laurent; Gardier, Alain M.; Guilloux, Jean-Philippe; David, Denis J.

    2014-01-01

    Cognitive disturbances are often reported as serious incapacitating symptoms by patients suffering from major depressive disorders (MDDs). Such deficits have been observed in various animal models based on environmental stress. Here, we performed a complete characterization of cognitive functions in a neuroendocrine mouse model of depression based on a chronic (4 weeks) corticosterone administration (CORT). Cognitive performances were assessed using behavioral tests measuring episodic (novel object recognition test, NORT), associative (one-trial contextual fear conditioning, CFC), and visuo-spatial (Morris water maze, MWM; Barnes maze, BM) learning/memory. Altered emotional phenotype after chronic corticosterone treatment was confirmed in mice using tests predictive of anxiety or depression-related behaviors. In the NORT, CORT-treated mice showed a decrease in time exploring the novel object during the test session and a lower discrimination index compared to control mice, characteristic of recognition memory impairment. Associative memory was also impaired, as observed with a decrease in freezing duration in CORT-treated mice in the CFC, thus pointing out the cognitive alterations in this model. In the MWM and in the BM, spatial learning performance but also short-term spatial memory were altered in CORT-treated mice. In the MWM, unlike control animals, CORT-treated animals failed to learn a new location during the reversal phase, suggesting a loss of cognitive flexibility. Finally, in the BM, the lack of preference for the target quadrant during the recall probe trial in animals receiving corticosterone regimen demonstrates that long-term retention was also affected in this paradigm. Taken together, our results highlight that CORT-induced anxio-depressive-like phenotype is associated with a cognitive deficit affecting all aspects of memory tested. PMID:24822041

  2. Cavitation in water under tension near the freezing point

    SciTech Connect

    Sosikov, V. A., E-mail: vaso@icp.ac.ru; Utkin, A. V.; Fortov, V. E. [Russian Academy of Sciences, Institute of Problems of Chemical Physics (Russian Federation)

    2008-05-15

    Experiments are reported on cavitation in water at an initial temperature of 0.7 deg. C under the dynamic tension created when a compression wave interacts with a free liquid surface. It is found that the tensile strength of water increases from 20 to 50 MPa as the strain rate is varied from 1.8 x 10{sup 4} to 5.2 x 10{sup 4} s{sup -1}. It is shown that the phase state of water obtained in experiments is in a double metastable region.

  3. Metabolic Activity of Permafrost Bacteria below the Freezing Point

    PubMed Central

    Rivkina, E. M.; Friedmann, E. I.; McKay, C. P.; Gilichinsky, D. A.

    2000-01-01

    Metabolic activity was measured in the laboratory at temperatures between 5 and ?20°C on the basis of incorporation of 14C-labeled acetate into lipids by samples of a natural population of bacteria from Siberian permafrost (permanently frozen soil). Incorporation followed a sigmoidal pattern similar to growth curves. At all temperatures, the log phase was followed, within 200 to 350 days, by a stationary phase, which was monitored until the 550th day of activity. The minimum doubling times ranged from 1 day (5°C) to 20 days (?10°C) to ca. 160 days (?20°C). The curves reached the stationary phase at different levels, depending on the incubation temperature. We suggest that the stationary phase, which is generally considered to be reached when the availability of nutrients becomes limiting, was brought on under our conditions by the formation of diffusion barriers in the thin layers of unfrozen water known to be present in permafrost soils, the thickness of which depends on temperature. PMID:10919774

  4. Metabolic activity of permafrost bacteria below the freezing point

    NASA Technical Reports Server (NTRS)

    Rivkina, E. M.; Friedmann, E. I.; McKay, C. P.; Gilichinsky, D. A.

    2000-01-01

    Metabolic activity was measured in the laboratory at temperatures between 5 and -20 degrees C on the basis of incorporation of (14)C-labeled acetate into lipids by samples of a natural population of bacteria from Siberian permafrost (permanently frozen soil). Incorporation followed a sigmoidal pattern similar to growth curves. At all temperatures, the log phase was followed, within 200 to 350 days, by a stationary phase, which was monitored until the 550th day of activity. The minimum doubling times ranged from 1 day (5 degrees C) to 20 days (-10 degrees C) to ca. 160 days (-20 degrees C). The curves reached the stationary phase at different levels, depending on the incubation temperature. We suggest that the stationary phase, which is generally considered to be reached when the availability of nutrients becomes limiting, was brought on under our conditions by the formation of diffusion barriers in the thin layers of unfrozen water known to be present in permafrost soils, the thickness of which depends on temperature.

  5. Postpartum depression

    PubMed Central

    Pearlstein, Teri; Howard, Margaret; Salisbury, Amy; Zlotnick, Caron

    2014-01-01

    Postpartum depression (PPD) affects up to 15% of mothers. Recent research has identified several psychosocial and biologic risk factors for PPD. The negative short-term and long-term effects on child development are well-established. PPD is under recognized and under treated. The obstetrician and pediatrician can serve important roles in screening for and treating PPD. Treatment options include psychotherapy and antidepressant medication. Obstacles to compliance with treatment recommendations include access to psychotherapists and concerns of breastfeeding mothers about exposure of the infant to antidepressant medication. Further research is needed to examine systematically the short-term and long-term effect of medication exposure through breastmilk on infant and child development. PMID:19318144

  6. Neurological signs and late-life depressive symptoms in a community population: the ESPRIT Study

    E-print Network

    Boyer, Edmond

    1 Neurological signs and late-life depressive symptoms in a community population: the ESPRIT Study: Neurological signs, Late-life Depression, Depressive symptoms, Old age, Neurodegenerative theory Key points-level depression but were more likely to be present in those with a lifetime history of neurological disorder

  7. Immersion freezing of different kinds of combustion ashes

    NASA Astrophysics Data System (ADS)

    Augustin-Bauditz, Stefanie; Grawe, Sarah; Hellner, Lisa; Wex, Heike; Pettersson, Jan B. C.; Stratmann, Frank

    2015-04-01

    Ice particles in the atmosphere influence both, weather and climate. Therefore it is important to know which kind of particles can act as ice nucleating particles (INP) under atmospheric conditions. In the last years, a lot of effort has been made to investigate the freezing abilities of natural INPs such as dusts and biological particles (Murray et al., 2012, Hoose and Möhler, 2012). However, there are only a few investigations concerning the ice nucleation ability of combustion ashes, which are the remains of fossil fuel and wood combustion and thus a possible source for anthropogenic INPs. Ash particles have similar compositions as mineral dust particles. However, the actual contribution of combustion ash particles to the atmospheric ice nucleation is rather unclear. A recent study by Umo et al. (2014) showed that combustion ashes could have a significant impact on the ice nucleation in clouds and thus should be the focus of further research. Ash particles can be lifted to the atmosphere by wind (bottom ashes) or directly during the combustion process (fly ashes). In the present study we investigated the freezing behavior of bottom ash particles which originated from wood as well as from coal. Additionally we investigated particles from fly ash from a coal-fired power plant. Particles were generated by dry dispersion and afterwards size selected with a differential mobility analyzer (DMA). The immersion freezing ability of the different ash particles was quantified utilizing the Leipzig Aerosol Cloud Interaction Simulator (LACIS, Hartmann et al., 2011), where exactly one size segregated ash particle is immersed in a droplet. We found significant differences between the freezing abilities of the different ash types. Particles from wood bottom ashes initiate freezing at rather low temperatures near the homogenous freezing point (around -36°C). Particles from coal bottom ashes show significant higher ice nucleation abilities than the wood bottom ash, with observed freezing temperatures similar to those of clay minerals (around -30°C). The particles from the fly ash showed the best freezing ability, which was significantly higher than the freezing ability of the clay minerals but still not as good as that of K-feldspar. Hartmann, S., Niedermeier, D., Voigtländer, J., Clauss, T., Shaw, R. A., Wex, H., Kiselev, A., and Stratmann, F.: Atmos. Chem. Phys., 11, 1753-1767, doi:10.5194/acp-11-1753-2011, 2011. Hoose, C. and O. Möhler, Atmos. Chem. Phys., 12, 9817-9854, 2012. Murray, B. J., O'Sullivan, D., Atkinson, J. D. and Webb, M. E., Chem. Soc. Rev., 41, 6519-6554, 2012. Umo N. S., Murray B. J., Baeza-Romero M. T., Jones J. M., Lea-Langton A. R., Malkin T. L., O'Sullivan D., Plane J. M. C. and Williams A., Atmos. Chem. Phys. Discuss., 14, 28845-28883, 2014

  8. Spray-freezing freeze substitution (SFFS) of cell suspensions for improved preservation of ultrastructure.

    PubMed

    Fields, S D; Strout, G W; Russell, S D

    1997-08-01

    Some unicellular organisms present challenges to chemical fixations that lead to common, yet obvious, artifacts. These can be avoided in entirety by adapting spray-freezing technology to ultrarapidly freeze specimens for freeze substitution. To freeze specimens, concentrated suspensions of cells ranging in diameter from 0.5-30 pm were sprayed with an airbrush at 140-200 kPa (1.05-1.5 torr; 20.3-29.0 psi) into a nylon mesh transfer basket submerged in liquid propane. After freezing, the mesh basket containing the frozen sample was lifted out of the chamber, drained and transferred through several anhydrous acetone rinses at 188 K (-85 degrees C). Freeze substitution was conducted in 1% tannic acid/1% anhydrous glutaraldehyde in acetone at 188 K (-85 degrees C), followed by 1% OsO4/acetone at 277 K (4 degrees C). Freeze substitution was facilitated using a shaking table to provide gentle mixing of the substitution medium on dry ice. High quality freezing was observed in 70% of spray-frozen dinoflagellate cells and in 95% of spray-frozen cyanobacterial cells. These could be infiltrated and observed directly; however, overall ultrastructural appearance and membrane contrast were improved when the freeze-substituted cells were rehydrated and post-fixed in aqueous OSO4, then dehydrated and embedded in either Spurr's or Epon resin. Ultrastructural preservation using this ultrarapid freezing method provided specimens that were consistently superior to those obtainable in even the best comparable chemical fixations. PMID:9264343

  9. Assessment of depression in medical patients: A systematic review of the utility of the Beck Depression Inventory-II

    PubMed Central

    Wang, Yuan-Pang; Gorenstein, Clarice

    2013-01-01

    To perform a systematic review of the utility of the Beck Depression Inventory for detecting depression in medical settings, this article focuses on the revised version of the scale (Beck Depression Inventory-II), which was reformulated according to the DSM-IV criteria for major depression. We examined relevant investigations with the Beck Depression Inventory-II for measuring depression in medical settings to provide guidelines for practicing clinicians. Considering the inclusion and exclusion criteria seventy articles were retained. Validation studies of the Beck Depression Inventory-II, in both primary care and hospital settings, were found for clinics of cardiology, neurology, obstetrics, brain injury, nephrology, chronic pain, chronic fatigue, oncology, and infectious disease. The Beck Depression Inventory-II showed high reliability and good correlation with measures of depression and anxiety. Its threshold for detecting depression varied according to the type of patients, suggesting the need for adjusted cut-off points. The somatic and cognitive-affective dimension described the latent structure of the instrument. The Beck Depression Inventory-II can be easily adapted in most clinical conditions for detecting major depression and recommending an appropriate intervention. Although this scale represents a sound path for detecting depression in patients with medical conditions, the clinician should seek evidence for how to interpret the score before using the Beck Depression Inventory-II to make clinical decisions. PMID:24141845

  10. Microbial analysis and survey test of gamma-irradiated freeze-dried fruits for patient's food

    NASA Astrophysics Data System (ADS)

    Park, Jae-Nam; Sung, Nak-Yun; Byun, Eui-Hong; Byun, Eui-Baek; Song, Beom-Seok; Kim, Jae-Hun; Lee, Kyung-A.; Son, Eun-Joo; Lyu, Eun-Soon

    2015-06-01

    This study examined the microbiological and organoleptic qualities of gamma-irradiated freeze-dried apples, pears, strawberries, pineapples, and grapes, and evaluated the organoleptic acceptability of the sterilized freeze-dried fruits for hospitalized patients. The freeze-dried fruits were gamma-irradiated at 0, 1, 2, 3, 4, 5, 10, 12, and 15 kGy, and their quality was evaluated. Microorganisms were not detected in apples after 1 kGy, in strawberries and pears after 4 kGy, in pineapples after 5 kGy, and in grapes after 12 kGy of gamma irradiation. The overall acceptance score, of the irradiated freeze-dried fruits on a 7-point scale at the sterilization doses was 5.5, 4.2, 4.0, 4.1, and 5.1 points for apples, strawberries, pears, pineapples, and grapes, respectively. The sensory survey of the hospitalized cancer patients (N=102) resulted in scores of 3.8, 3.7, 3.9, 3.9, and 3.7 on a 5-point scale for the gamma-irradiated freeze-dried apples, strawberries, pears, pineapples, and grapes, respectively. The results suggest that freeze-dried fruits can be sterilized with a dose of 5 kGy, except for grapes, which require a dose of 12 kGy, and that the organoleptic quality of the fruits is acceptable to immuno-compromised patients. However, to clarify the microbiological quality and safety of freeze-dried fruits should be verified by plating for both aerobic and anaerobic microorganisms.

  11. Chilled water coil freeze protection via internal drying

    SciTech Connect

    LaRocca, D.V. [Yale Univ. School of Medicine, New Haven, CT (United States). Building Services and Operations Dept.

    1997-12-01

    Winter lay-up for chilled water coils has been a problem for as long as there has been air conditioning. A frozen coil may be so seriously damaged that it must be replaced. Also, as the coil thaws, significant flooding of adjacent areas may result. Over the years, various methods of freeze protection have been used. These methods include using a glycol solution to lower the freezing point, blowing the coil clear with compressed air, or installing coils that incorporate freeze plugs in the coil design. Each of these methods has one or more significant drawbacks. A new approach, nicknamed ``The LaRocca Solution`` is a simple procedure. Air is blown continuously through the coils to ensure that they become completely dry and remain so. Instead of using a separate blower or air compressor to blow out the water, the supply fan itself is used. On most medium- and high-pressure HVAC systems, the static pressure produced by the supply fan is sufficient to overcome the internal resistance of the coil tubes. One simply configures the chilled water piping in a manner that permits the coils to be drained by gravity and then purged by the discharge of the fan. The fan does all the work.

  12. Sensitivity of liquid clouds to homogenous freezing parameterizations

    PubMed Central

    Herbert, Ross J; Murray, Benjamin J; Dobbie, Steven J; Koop, Thomas

    2015-01-01

    Water droplets in some clouds can supercool to temperatures where homogeneous ice nucleation becomes the dominant freezing mechanism. In many cloud resolving and mesoscale models, it is assumed that homogeneous ice nucleation in water droplets only occurs below some threshold temperature typically set at ?40°C. However, laboratory measurements show that there is a finite rate of nucleation at warmer temperatures. In this study we use a parcel model with detailed microphysics to show that cloud properties can be sensitive to homogeneous ice nucleation as warm as ?30°C. Thus, homogeneous ice nucleation may be more important for cloud development, precipitation rates, and key cloud radiative parameters than is often assumed. Furthermore, we show that cloud development is particularly sensitive to the temperature dependence of the nucleation rate. In order to better constrain the parameterization of homogeneous ice nucleation laboratory measurements are needed at both high (>?35°C) and low (Points Homogeneous freezing may be significant as warm as ?30°C Homogeneous freezing should not be represented by a threshold approximation There is a need for an improved parameterization of homogeneous ice nucleation PMID:26074652

  13. Depression and College Students

    E-print Network

    Kane, Andrew S.

    Depression and College Students Answers to college students' frequently asked questions about depression #12;2 M any people experience the first symptoms of depression during their college years. Unfortunately, many college students who have depression aren't getting the help they need. They may not know

  14. The Great Depression

    NSDL National Science Digital Library

    RandyandAmber

    2007-11-30

    Students will understand the personal impact of the depression on the lives of Americans. We will follow Utah\\'s Social Studies core curriculum Standard 6: Students will understand how the Great Depression and the New Deal affected the United States. Objective 1 Investigate the impact of the Great Depression on the United States. * Analyze the major causes of the Great Depression. ...

  15. Asymmetric Synaptic Depression in

    Microsoft Academic Search

    Mircea I. Chelaru; Valentin Dragoi

    Synaptic depression is essential for controlling the balance be- tween excitation and inhibition in cortical networks. Several studies have shown that the depression of intracortical synapses is asymmetric, that is, inhibitory synapses depress less than excit- atory ones. Whether this asymmetry has any impact on cortical function is unknown. Here we show that the differential depression of intracortical synapses provides

  16. Exploring the Nature of Contact Freezing

    NASA Astrophysics Data System (ADS)

    Kiselev, A. A.; Hoffmann, N.; Duft, D.; Leisner, T.

    2012-12-01

    The freezing of supercooled water droplets upon contact with aerosol particles (contact nucleation of ice) is the least understood mechanism of ice formation in atmospheric clouds. Although experimental evidences suggest that some aerosols can be better IN in the contact than in the immersion mode (that is, triggering ice nucleation at higher temperature), no final explanation of this phenomena currently exists. On the other hand, the contact freezing is believed to be responsible for the enhanced rate of secondary ice formation occasionally observed in LIDAR measurements in the cold mixed phase clouds. Recently we have been able to show that the freezing of supercooled droplets electrodynamically levitated in the laminar flow containing mineral dust particles (kaolinite) is a process solely governed by a rate of collisions between the supercooled droplet and the aerosol particles. We have shown that the probability of droplet freezing on a single contact with aerosol particle may differ over an order of magnitude for kaolinite particles having different genesis and morphology. In this presentation we extend the study of contact nucleation of ice and compare the IN efficiency measured for DMA-selected kaolinite, illite and hematite particles. We show that the freezing probability increases towards unity as the temperature decreases and discuss the functional form of this temperature dependence. We explore the size dependence of the contact freezing probability and show that it scales with the surface area of the particles, thus resembling the immersion freezing behavior. However, for all minerals investigated so far, the contact freezing has been shown to dominate over immersion freezing on the short experimental time scales. Finally, based on the combined ESEM and electron microprobe analysis, we discuss the significance of particle morphology and variability of chemical composition on its IN efficiency in contact mode.

  17. Preservation of surface lipids and determination of ultrastructure of Mycobacterium kansasii by freeze-substitution.

    PubMed Central

    Paul, T R; Beveridge, T J

    1994-01-01

    The cell wall architecture of a slowly growing mycobacterium, Mycobacterium kansasii, was examined by freeze-substitution following growth in vitro. Freeze-substituted bacteria were marked by the presence of an electron-translucent space (or electron-transparent zone [ETZ] described by previous workers [T. Yamamoto, M. Nishiura, N. Harada, and T. Imaeda, Int. J. Lepr. 26:111-114, 1958]) surrounding the majority of cells. At least two morphotypes of mycobacteria were revealed by freeze-substitution. In the first, a relatively thin (11 +/- 2.3 to 3.5 +/- 3.1 nm), uniform ETZ surrounded intact cells which contained cytoplasm filled with well-stained ribosomes and a DNA nucleoid distributed throughout the cell. The second morphotype consisted of a small proportion of organisms that were distorted in shape and were surrounded by a much thicker (59 +/- 2.6 to 198 +/- 2.5 nm) ETZ in areas of the cell which appeared to have retracted from the space it had originally occupied, leaving depressions in the ETZ. The lipid nature of the ETZ was demonstrated because cells were devoid of an ETZ when organisms were freeze-substituted in the absence of osmium tetroxide in the substitution medium or treated with neutral lipid solvents (acetone or ethanol) before freeze-substitution. Moreover, thin-layer chromatography of acetone or ethanol extracts obtained from solvent-treated cells identified a lipid component which corresponded to the M. kansasii-specific phenolic glycolipid. In contrast, negligible amounts of glycolipids were detected in extracts obtained from control HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) buffer-treated cells, and these cells retained an ETZ. These results demonstrate that species-specific phenolic glycolipids are essential components in the architecture of the M. kansasii ETZ. Furthermore, we show that freeze-substitution is a reliable technique for the retention and precise preservation of lipid-containing polymers in the mycobacterial cell wall. Images PMID:8168915

  18. [Fatigue and depression].

    PubMed

    Hell, Daniel

    2015-04-22

    Fatigue is characterised in an overview of the literature as a specific phenomenon of depression. Its differential diagnosis is discussed. Distinctions and correspondences to burnout are elaborated. Fatigue is not an obligatory symptom of depressive episodes, although it can contribute to depressive developments. The importance of fatigue in depressive episodes and its therapy is shown with the help of a circular model of depression. PMID:26072598

  19. Freeze-out Conditions from Lattice QCD

    E-print Network

    Swagato Mukherjee

    2012-11-29

    We describe a procedure for determination of freeze-out parameters of heavy-ion collisions through direct comparisons between experimentally measured higher order cumulants of charge fluctuations and first principle (lattice) QCD calculations.

  20. Freezing and Thawing Human Embryonic Stem Cells

    NSDL National Science Digital Library

    Kent, Lia

    Lia Kent, of Stemgent's Research and Development team, has created this video to demonstrate "the proper technique for rapidly thawing hES cells from liquid nitrogen stocks, plating them on mouse embryonic feeder cells, and slowly freezing them for long-term storage." The video is also accompanied by protocols for thawing and freezing hES cells, discussion, materials, references, a forum for comments, and a PDF of the full text.

  1. Depression Among Methamphetamine Users

    PubMed Central

    Glasner-Edwards, Suzette; Marinelli-Casey, Patricia; Hillhouse, Maureen; Ang, Alfonso; Mooney, Larissa J.; Rawson, Richard

    2009-01-01

    Although depression is highly comorbid with substance use disorders, little is known about the clinical course and outcomes of methamphetamine (MA) users with depressive symptoms and syndromes. In this study of MA-dependent individuals entering psychosocial treatment, we predicted that (1) depressive symptoms would decline during treatment, an effect that would vary as a function of MA use and (2) depression diagnoses post-treatment would be associated with poorer outcomes. Participants (N = 526) were assessed for depression, substance use, and psychosocial outcomes at baseline, treatment discharge, and 3-year follow-up. Depressive symptoms declined significantly during treatment, an effect that was greatest among those who abstained from MA. Major depression at follow-up was associated with poorer MA use outcomes and impairment across multiple domains of functioning. The findings highlight the relationship of depressive symptoms and diagnoses to treatment outcomes, and suggest a need for further studies of depression in populations using MA. PMID:19363377

  2. Ultrastructural metabolic activity following quick-freezing and freeze-substitution in tetrahydrofuran in the superior cervical ganglion

    Microsoft Academic Search

    Paul J. Yarowsky; Alan F. Boyne

    1989-01-01

    Summary A method of quick-freezing and freeze-substitution has been developed for localizing diffusible substances such as 2-deoxyglucose-6-phosphate (2-DG-6-P) ultrastructurally in neural tissue. Quick-freezing under pressure provides well preserved tissue down to 30–35 µm from the surface. This allows blocks of neural tissue to be quick-frozen and analysed for diffusible substances in areas removed from the freezing face. Freeze-substitution in tetrahydrofuran

  3. Entropic Aspects of Supercooled Droplet Freezing ALEXANDER KOSTINSKI AND WILL CANTRELL

    E-print Network

    Kostinski, Alex

    pressures1 and then using the Clausius­Clapeyron equation as well as the triple-point identity, in final form 27 December 2007) ABSTRACT The freezing of supercooled water droplets in the atmosphere, with an emphasis on the entropic aspects of the problem, is examined. Supercooled water is a metastable state and

  4. Coincidence probability as a measure of the average phase-space density at freeze-out

    E-print Network

    A. Bialas; W. Czyz; K. Zalewski

    2006-02-08

    It is pointed out that the average semi-inclusive particle phase-space density at freeze-out can be determined from the coincidence probability of the events observed in multiparticle production. The method of measurement is described and its accuracy examined.

  5. The equilibrated state of freezing as a basis for distinguishing lethal stresses of freezing in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A model for coordination of stresses that limit winterhardiness in plants based on the thermodynamic equilibrated state of freezing and melting provides a rational basis for distinction of freeze-induced energies which can stress and injure living organisms in various ways. The departure from equili...

  6. Influence of chemical and freezing fixation methods in the freeze-fracture of stratum corneum.

    PubMed

    López, O; López-Iglesias, C; Cócera, M; Walther, P; Parra, J L; De La Maza, A

    2004-06-01

    A comparison between two fixation techniques for freeze-fracture was established. Stratum corneum (SC) samples from pig epidermis were fixed using high-pressure freezing (HPF) and using plunging in propane freezing; the latter after chemical fixation. Then, frozen samples were freeze-fractured, coated with platinum-carbon, and visualized using a high-resolution low-temperature scanning electron microscope and a transmission electron microscope. Our results indicate that the plane of freeze-fracture was different depending on the fixation and freezing methodology used. In the samples frozen by HPF without chemical fixation, the fracture plane laid mainly between the lipid lamellae. However, when chemical fixation and plunging in propane freezing was used, the fracture plane did not show preference to a specific way. Plunging in propane freezing of chemically fixed samples, on the other hand, provides a more homogeneous fracture behaviour. Thus, depending on the methodology used, we can favour a visualization of either lipid or protein domains of the SC. These results could be very useful in future ultrastructural studies in order to facilitate the microscopic visualization and interpretation of the complex images such as those of SC and even of other samples in which different domains coexist. PMID:15099572

  7. Depression and Chronic Illness

    MedlinePLUS

    ... related to increased symptoms of depression. Examples of chronic illness include: • heart disease • Parkinson’s disease • multiple sclerosis • stroke • ... not be dismissed as a “normal” reaction to chronic illness, but it is common. Depression is a problem ...

  8. Irrational Beliefs in Depression

    ERIC Educational Resources Information Center

    Nelson, R. Eric

    1977-01-01

    To examine the hypothesis that certain types of irrational beliefs covary with the severity of depression, 156 undergraduates completed the Beck Depression Inventory and R. G. Jone's Irrational Beliefs Test (IBT). (Author)

  9. Managing your depression - teens

    MedlinePLUS

    ... Jansen KL, Cloy JA. Treatment of childhood and adolescent depression. Am Fam Physician . 2012;86:442-448. PMID ... Services Task Force. Screening and treatment for major depressive ... Services Task Force Recommendation Statement. Pediatrics . ...

  10. Depression in Parkinson's disease.

    PubMed

    Rihmer, Zoltán; Gonda, Xénia; Döme, Péter

    2014-07-30

    The prevalence of major and minor depression in Parkinson's disease is around 30-40% but, unfortunately, depression remains frequently underrecognized and often undertreated. However, recognition and appropriate treatment of depression in patients with Parkinson's disease is essential for improving the cross-sectional picture and longitudinal course. This review focuses on the epidemiology, pathophysiology and different treatment modalities of depression in Parkinson's disease. PMID:25509363

  11. Freeze-drying of lactic acid bacteria.

    PubMed

    Fonseca, Fernanda; Cenard, Stéphanie; Passot, Stéphanie

    2015-01-01

    Lactic acid bacteria are of great importance for the food and biotechnology industry. They are widely used as starters for manufacturing food (e.g., yogurt, cheese, fermented meats, and vegetables) and probiotic products, as well as for green chemistry applications. Freeze-drying or lyophilization is a convenient method for preservation of bacteria. By reducing water activity to values below 0.2, it allows long-term storage and low-cost distribution at suprazero temperatures, while minimizing losses in viability and functionality. Stabilization of bacteria via freeze-drying starts with the addition of a protectant solution to the bacterial suspension. Freeze-drying includes three steps, namely, (1) freezing of the concentrated and protected cell suspension, (2) primary drying to remove ice by sublimation, and (3) secondary drying to remove unfrozen water by desorption. In this chapter we describe a method for freeze-drying of lactic acid bacteria at a pilot scale, thus allowing control of the process parameters for maximal survival and functionality recovery. PMID:25428024

  12. Freeze drying for morphological control of inter-penetrating polymer networks

    NASA Technical Reports Server (NTRS)

    Hansen, Marion G.; Pater, Ruth H.

    1990-01-01

    The intrinsic brittleness of BMI resins can be reduced through the creation of an interpenetrating network (IPN) of BMI with a reactive-encapped thermoplastic, such as the presently considered polyimidesulfone, PISO2. The PISO2 and BMI were dissolved in a common solvent, which was then removed from the constituents by freeze drying; in an alternative method, an IPN was formed through dissolution of the constituent in a common solvent with either high or low melting point, followed by evaporative removal of the solvent. The effectiveness of the freeze-drying approach for morphological control is evaluated.

  13. Freezing-thawing action in the deterioration of the stones of Chambord Castle

    NASA Astrophysics Data System (ADS)

    Alomari, Asaad; Brunetaud, Xavier; Beck, Kevin; Al-Mukhtar, Muzahim

    2013-04-01

    Limestone is very common in architecture (monuments and cultural heritage buildings) and used in the sculptures. The soft and porous limestone soaks up water and show weathering patterns and forms: alveolar weathering, granular disintegration, efflorescences. Freezing-thawing actions can be considered as one of the processes that contribute in the deterioration of stones located in the "cold regions" characterized with air temperatures below freezing point temperature. The amount of water within the pore space of the stones is a crucial factor of the decay. The experimental work presented in this paper is a part of a research program that aims to study the mechanisms that lead to the degradation of stone building materials due to the variation of climatic conditions. The analysis of the meteorological data of the field around the castle of Chambord shows the magnitude of temperature variations and the frequency of freezing-thawing cycles. The critical degrees of saturation at which the stone start to deteriorate after treatment with freezing-thawing cycles were examined in the tests conducted. The study concerns two porous limestone used in the construction and conservation of Chambord castle; highly porous Tuffeau stone having a total porosity of about 48 %, and medium porous Richemont stone with a total porosity of 27 %. Richemont stone has been used as a substitute stone of the degraded Tuffeau stone on the castle. The main physical properties, total porosity, apparent dry density and skeleton density and sound velocity for mechanical properties were measured for the stone samples before and during freezing-thawing cycles. ASTM (D5312-04) procedure was applied in the freezing-thawing tests. Tuffeau and Richmond samples were prepared at nine different degrees of saturations; 0, 20, 40, 70, 80, 85, 90, 95 and 100%, and properties were measured after different freezing-thawing cycles conditions; 2, 4, 8, 12, 16, 20, 30 and 50 cycles. The results of these tests show that when the degree of saturation exceeds 80-85%, freeze-thaw damage is inevitable even for a very few freeze-thaw cycles. Moreover, results indicate that the two studied stones have similar critical degree of saturation of about 85 %. This can be attributed to the similar percentage of macro-pores in the two tested stones. Finally, the critical degree of saturation was not changed after increasing the number of freezing-thawing cycles, thus the critical degree of saturation can be considered as a stone property.

  14. Importance of Depression in Diabetes.

    ERIC Educational Resources Information Center

    Lustman, Patrick J.; Clouse, Ray E.; Anderson, Ryan J.

    Depression doubles the likelihood of comorbid depression, which presents as major depression in 11% and subsyndromal depression in 31% of patients with the medical illness. The course of depression is chronic, and afflicted patients suffer an average of one episode annually. Depression has unique importance in diabetes because of its association…

  15. The Great Depression

    Microsoft Academic Search

    Peter Temin

    1994-01-01

    This history of the Great Depression was prepared for The Cambridge Economic History of the United States. It describes real and imagined causes of the Depression, bank failures and deflation, the Fed and the gold standard, the start of recovery, the first New Deal, and the second New Deal. I argue that adherence to the gold standard caused the Depression,

  16. Prevention of Depression.

    ERIC Educational Resources Information Center

    Compas, Bruce E.; Connor, Jennifer; Wadsworth, Martha

    Substantial numbers of children and adolescents experience symptoms of sadness, dysphoria, and other characteristics associated with depression. The nature of depression in children and adolescents has presented challenges in identification and definition. This chapter reviews research on depression in children and adolescents. Three current…

  17. Soil salinity increases survival of freezing in the enchytraeid Enchytraeus albidus.

    PubMed

    Silva, A L Patrício; Holmstrup, M; Kostal, V; Amorim, M J B

    2013-07-15

    Enchytraeus albidus is a freeze-tolerant enchytraeid found in diverse habitats, ranging from supralittoral to terrestrial and spanning temperate to arctic regions. Its freeze tolerance is well known but the effect of salinity in this strategy is still poorly understood. We therefore studied the combined effect of salinity (0, 15, 35, 50‰ NaCl) and sub-zero temperatures (-5, -14, -20°C) on the freeze tolerance of E. albidus collected from two distinct geographical regions (Greenland and Germany). A full factorial design was used to study survival, and physiological and biochemical end points. The effect of salinity on the reproduction of German E. albidus was also assessed. Exposure for 48 h to saline soils prior to cold exposure triggered an increase in osmolality and decrease in water content. Worms exposed to saline soils had an improved survival of freezing compared to worms frozen in non-saline soils, particularly at -20°C (survival more than doubled). Differential scanning calorimetry measurements showed that the fraction of water frozen at -5 and -14°C was lower in worms exposed to 35‰ NaCl than in control worms. The lowering of ice content by exposure to saline soils was probably the main explanation for the better freeze survival in saline-exposed worms. Glucose increased with decreasing temperature, but was lower in saline than in non-saline soils. Thus, glucose accumulation patterns did not explain differences in freeze survival. Overall, the physiological responses to freezing of E. albidus from Greenland and Germany were similar after exposure to saline soils. Soil salinity up to 30‰ improved reproduction by a factor of ca. 10. PMID:23531829

  18. Should practitioners promote physical activity as a treatment for depression?

    PubMed

    Donaghy, M; Taylor, A H

    2010-06-01

    For many years, experts have been debating the pros and cons of exercise for depression. Proponents of exercise for depression point to those clinical trials which have shown that exercise improves mood, while sceptics point out the methodological problems in many of the apparently positive trials, and the uncertainties around the acceptability of exercise as a treatment for depression. Here two experts critically review the evidence around exercise for depression, provide arguments for and against the promotion of physical activity as a treatment for depression, explore issues around the generalisability of exercise as a treatment for depression and look to the future by discussing ongoing trials that will provide more evidence to inform this important debate. PMID:21125058

  19. Freeze verification: time for a fresh approach

    SciTech Connect

    Paine, C.

    1983-01-01

    The administration's claim that some elements of a comprehensive nuclear freeze are unverifiable does not specify the nature of those elements and whether they represent a real threat to national security if we trusted the USSR to comply. The author contends that clandestine development of new weapons will have little strategic effect since both sides already have total destructive power. The risks of noncompliance are largely political and less than the risks of continued arms buildup. Since the USSR would also want the US to be bound by freeze terms, deterrence would come from mutual benefit. Hardliners argue that cheating is easier in a closed society; that our democracy would tend to relax and the USSR would move ahead with its plans for world domination. The author argues that, over time, a freeze would diminish Soviet confidence in its nuclear war fighting capabilities and that adequate verification is possible with monitoring and warning arrangements. (DCK)

  20. Study on Freezing of a Single Droplet

    NASA Astrophysics Data System (ADS)

    Fumoto, Koji; Yamagishi, Hideaki; Ikegawa, Masahiro

    The freezing characteristics of a single water droplet placed on the column edge were visually investigated using a video camera. The temperatures of the edge face and the environment air were independently controlled. The solidification process of the water droplet was discussed based on the many pictures obtained. The experimental results indicated that the freezing time of droplet was strongly affected by the edge temperature. Furthermore, we found that the water dispersion thermosensitivity slurry was effective for the observation of the temperature of the droplet. Consequently, it was indicated that the heat transfer characteristics of the droplet under freezing condition were mainly affected by both temperature of the air and surface of the flat plate.

  1. Directional freezing for large volume cryopreservation.

    PubMed

    Saragusty, Joseph

    2015-01-01

    Cryopreservation is currently the method of choice when it comes to long-term preservation of viable biological samples. The process, and consequently the volume of the sample, however, is limited by the ability to achieve homogenous and efficient heat removal. When this cannot be properly managed, ice crystals will grow uncontrollably resulting in extensive damage to the cryopreserved cells or tissues. Directional freezing is a technique that can be used to precisely control heat dissipation and ice crystal growth and morphology even when freezing large volumes. The technique has been used over the years to cryopreserve spermatozoa, oocytes, embryos, tissue slices and whole organs from a wide variety of domestic and wild species. In this chapter a protocol for directional freezing of spermatozoa is described and its benefits and shortcomings are discussed. PMID:25428019

  2. Distinct seasonality of depressive episodes differentiates unipolar depressive patients with and without depressive mixed states

    Microsoft Academic Search

    Tetsuya Sato; Ronald Bottlender; Marcus Sievers; Hans-Jürgen Möller

    2006-01-01

    BackgroundThe bipolar nature of unipolar depression with depressive mixed sates (DMX) needs further validation studies. The seasonality of depressive episodes is indicated to be different between unipolar and bipolar depressions. We therefore explored the seasonal pattern of depressive episodes in unipolar depressive patients with DMX.

  3. Infrared thermography for monitoring of freeze-drying processes: instrumental developments and preliminary results.

    PubMed

    Emteborg, Håkan; Zeleny, Reinhard; Charoud-Got, Jean; Martos, Gustavo; Lüddeke, Jörg; Schellin, Holger; Teipel, Katharina

    2014-07-01

    Coupling an infrared (IR) camera to a freeze dryer for on-line monitoring of freeze-drying cycles is described for the first time. Normally, product temperature is measured using a few invasive Pt-100 probes, resulting in poor spatial resolution. To overcome this, an IR camera was placed on a process-scale freeze dryer. Imaging took place every 120 s through a Germanium window comprising 30,000 measurement points obtained contact-free from -40 °C to 25 °C. Results are presented for an empty system, bulk drying of cheese slurry, and drying of 1 mL human serum in 150 vials. During freezing of the empty system, differences of more than 5 °C were measured on the shelf. Adding a tray to the empty system, a difference of more than 8 °C was observed. These temperature differences probably cause different ice structures affecting the drying speed during sublimation. A temperature difference of maximum 13 °C was observed in bulk mode during sublimation. When drying in vials, differences of more than 10 °C were observed. Gradually, the large temperature differences disappeared during secondary drying and products were transformed into uniformly dry cakes. The experimental data show that the IR camera is a highly versatile on-line monitoring tool for different kinds of freeze-drying processes. PMID:24902839

  4. Freezing precipitation in the Southeastern United States

    E-print Network

    Young, William Robert

    1978-01-01

    they assumed that the surface was at 1000 mb. U )~ CQ ~+10 CO LL| +5 CL & o LLt E O -~o CO FREEZI NG RAIN 0? RAI N MIXED PREC IP TYPES No CASES -10 -5 0 +5 SURFACE TEMP(V&ET euLEI) C Fig. 4. Decision graph developed by Hilworth... of surface temperature and thickness but with an 850-mb temperature less than or equal to O'C, A decision graph based on the rules devised by Tang is d-picted in Fig 5 ~ 21 +10 FREEZING RAiN FOR SNOVC, SLEET OR FREEZING RA I N:1QQQ- ~Q 0-mb THICK...

  5. Reversed freeze quench method near the solvent phase transition.

    PubMed

    Marchanka, Aliaksandr; van Gastel, Maurice

    2012-04-19

    Freeze quenching is a general method for trapping reaction intermediates on a (sub)millisecond time scale. The method relies on a mixing and subsequent rapid freezing of solutions of reactants. If the reaction is limited by diffusion, it may be advantageous to initially mix the reactants under conditions where the reaction does not proceed, e.g., by mixing them at low temperature as solids. The temperature may then be raised close to the melting point of the solvent. Depending on the viscosity of the solvent, the temperature can be raised either by heating or by applying laser pulses of nanosecond length with concomitant conversion of light into heat. A reduction of the dead time and a good control of the reaction speed in comparison to the standard freeze quench technique has been achieved with this method. The feasibility of the method in combination with EPR spectroscopy is verified by examining the important prototypical reductions of benzoquinone and 2,6-dichlorophenolindophenol by ascorbate as representatives for two-step redox reactions. By using light pulses of a laser, the reaction could be driven with rates lowered by 4 orders of magnitude as compared to room temperature reaction rates. This has allowed the observation of previously unobserved radical intermediates: the reduction of DCPIP by ascorbate is found to be strongly pH dependent. It proceeds via two one-electron steps at low pH, whereas at neutral pH, the reduction of DCPIP by ascorbate proceeds in a 1:2 stoichiometry followed by a disproportionation of the ascorbate radicals. PMID:22413925

  6. Physiological responses to freezing in hatchlings of freeze-tolerant and -intolerant turtles.

    PubMed

    Costanzo, Jon P; Baker, Patrick J; Lee, Richard E

    2006-09-01

    Freeze tolerance is a complex cold-hardiness adaptation that has independently evolved in a diverse group of organisms, including several ectothermic vertebrates. Because little is known about the mechanistic basis for freeze tolerance in reptiles, we compared responses to experimental freezing in winter-acclimatized hatchlings representing nine taxa of temperate North American turtles, including ones that tolerated freezing and others that did not. Viability rates of hatchlings frozen to -3 degrees C for 72 h ranged from 0 to 100%. Tolerance to freezing was poor in Sternotherus odoratus, Graptemys geographica and Trachemys scripta, intermediate in Chelydra serpentina, and high in Emydoidea blandingii, Chrysemys picta bellii, C. p. marginata, Malaclemys terrapin, and Terrapene ornata, and generally reflected the winter thermal ecology of each taxon. Plasma activity of lactate dehydrogenase (LDH), a novel in vivo index of freeze/thaw damage, corroborated viability assessments and demonstrated that cryoinjury occurred even in surviving turtles. Irrespective of taxon, cryoinjury tended to be higher in smaller individuals and in those having relatively low water contents; however, bases for these associations were not apparent. Screening for certain organic osmolytes that might promote freezing survival by colligatively reducing ice content and limiting cell dehydration showed that the plasma of unfrozen (control) turtles contained small quantities of glucose (1.3-5.8 mmol l(-1)) and lactate (0.6-3.2 mmol l(-1)) and modest amounts of urea (range of mean values for all taxa 8.2-52.3 mmol l(-1)). Frozen/thawed turtles of all taxa accumulated modest amounts of glucose and lactate that jointly raised the plasma solute concentration by 30-100 mmol l(-1). We conclude that organic osmolytes accumulated both before and during freezing may promote survival in species that have evolved a tolerance to freezing, but are not necessarily accumulated for that purpose. PMID:16758216

  7. Basic concepts of depression

    PubMed Central

    Paykel, Eugene S.

    2008-01-01

    This paper reviews concepts of depression, including history and classification. The original broad concept of melancholia included all forms of quiet insanity. The term depression began to appear in the nineteenth century as did the modern concept of affective disorders, with the core disturbance now viewed as one of mood. The 1930s saw the introduction of defined criteria into official diagnostic schemes. The modern separation into unipolar and bipolar disorder was introduced following empirical research by Angst and Perris in the 1960s. The partially overlapping distinctions between psychotic and neurotic depression, and between endogenous and reactive depression, started to generate debate in the 1920s, with considerable multivariate research in the 1960s. The symptom element in endogenous depression currently survives in melancholia or somatic syndrome. Life stress is common in various depressive pictures. Dysthymia, a valuable diagnosis, represents a form of what was regarded earlier as neurotic depression. Other subtypes are also discussed. PMID:18979941

  8. Marital Processes around Depression: A Gendered and Relational Perspective

    PubMed Central

    Thomeer, Mieke Beth; Umberson, Debra; Pudrovska, Tetyanna

    2015-01-01

    Despite extensive evidence of the importance of marriage and marital processes for mental health, little is known about the interpersonal processes around depression within marriage and the extent to which these processes are gendered. We use a mixed methods approach to explore the importance of gender in shaping processes around depression within marriage; we approach this in two ways. First, using quantitative longitudinal analysis of 2,601 couples from the Health and Retirement Study (HRS), we address whether depressive symptoms in one spouse shape the other spouse's depressive symptoms and whether men or women are more influential in this process. We find that a wife's depressive symptoms influence her husband's future depressive symptoms but a husband's depressive symptoms do not influence his wife's future symptoms. Second, we conduct a qualitative analysis of in-depth interviews with 29 couples wherein one or both spouses experienced depression to provide additional insight into how gender impacts depression and reactions to depression within marriage. Our study points to the importance of cultural scripts of masculinity and femininity in shaping depression and emotional processes within marriage and highlights the importance of applying a gendered couple-level approach to better understand the mental health effects of marital processes. PMID:25914855

  9. Protein Inhalation Powders: Spray Drying vs Spray Freeze Drying

    Microsoft Academic Search

    Yuh-Fun Maa; Phuong-Anh Nguyen; Theresa Sweeney; Steven J. Shire; Chung C. Hsu

    1999-01-01

    Purpose. To develop a new technique, spray freeze drying, for preparing protein aerosol powders. Also, to compare the spray freeze-dried powders with spray-dried powders in terms of physical properties and aerosol performance.

  10. 7 CFR 58.620 - Freezing and packaging rooms.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Compartments § 58.620 Freezing and packaging rooms. The rooms used for freezing and packaging frozen desserts...satisfactory air circulation and maintained in a clean and sanitary condition. The rooms shall be constructed in the same manner...

  11. 7 CFR 58.620 - Freezing and packaging rooms.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Compartments § 58.620 Freezing and packaging rooms. The rooms used for freezing and packaging frozen desserts...satisfactory air circulation and maintained in a clean and sanitary condition. The rooms shall be constructed in the same manner...

  12. 7 CFR 58.620 - Freezing and packaging rooms.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Compartments § 58.620 Freezing and packaging rooms. The rooms used for freezing and packaging frozen desserts...satisfactory air circulation and maintained in a clean and sanitary condition. The rooms shall be constructed in the same manner...

  13. 7 CFR 58.620 - Freezing and packaging rooms.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Compartments § 58.620 Freezing and packaging rooms. The rooms used for freezing and packaging frozen desserts...satisfactory air circulation and maintained in a clean and sanitary condition. The rooms shall be constructed in the same manner...

  14. OUHSC -Hiring Freeze Guidelines & Procedures (Updated February 2013)

    E-print Network

    Oklahoma, University of

    OUHSC - Hiring Freeze Guidelines & Procedures (Updated February 2013) Revised and effective-Tulsa operations and other operating locations, has revised its operating guidelines and procedures. Freeze transactions remain subject to standard OU policies, operating procedures and guidelines. All staff positions

  15. 40 CFR 52.1135 - Regulation for parking freeze.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Regulation for parking freeze. 52.1135 Section 52.1135...Massachusetts § 52.1135 Regulation for parking freeze. (a) Definitions: (1...land filling specifically designed for a parking facility in preparation for...

  16. Accuracy of Depression Screening Tools for Identifying Postpartum Depression Among Urban Mothers

    PubMed Central

    Chaudron, Linda H.; Szilagyi, Peter G.; Tang, Wan; Anson, Elizabeth; Talbot, Nancy L.; Wadkins, Holly I.M.; Tu, Xin; Wisner, Katherine L.

    2011-01-01

    Objective The goal was to describe the accuracy of the Edinburgh Postnatal Depression Scale (EPDS), Beck Depression Inventory II (BDI-II), and Postpartum Depression Screening Scale (PDSS) in identifying major depressive disorder (MDD) or minor depressive disorder (MnDD) in low-income, urban mothers attending well childcare (WCC) visits during the postpartum year. Design/Methods Mothers (N=198) attending WCC visits with their infants 0 to 14 months of age completed a psychiatric diagnostic interview (standard method) and 3 screening tools. The sensitivity and specificity of each screening tool were calculated in comparison with diagnoses of MDD or MDD/MnDD. Receiver operating characteristic curves were calculated and the areas under the curves for each tool were compared to assess accuracy for the entire sample (representing the postpartum year) and sub-samples (representing early, middle and late postpartum time frames). Optimal cut-points were calculated. Results At some point between 2 weeks and 14 months postpartum, 56% of mothers met criteria for either MDD (37%) or MnDD (19%). When used as a continuous measures, all scales performed equally well (areas under the curves of ? 0.8). With traditional cut-points, the measures did not perform at the expected levels of sensitivity and specificity. Optimal cut-points for the BDI-II (?14 for MDD, ?11 for MDD/MnDD) and EPDS (?9 for MDD, ?7 for MDD/MnDD) were lower than currently recommended. For the PDSS, the optimal cut-point was consistent with current guidelines for MDD (?80) but higher than recommended for MDD/MnDD (? 77). Conclusions Large proportions of low-income, urban mothers attending WCC visits experience MDD or MnDD during the postpartum year. The EPDS, BDI-II and PDSS have high accuracy in identifying depression but cutoff points may need to be altered to more accurately identify depression in urban, low-income mothers. PMID:20156899

  17. Unitarity Constraints on Asymmetric Freeze-In

    SciTech Connect

    Hook, Anson; /SLAC

    2011-08-15

    This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order. This note has shown that if two sectors are in thermal equilibrium with themselves, but not with each other, then the leading effect transferring conserved quantities between the two sectors is of order the the weak coupling connecting them to the third power. When freeze-in is used to produce a net baryon number density, the leading order effect comes from {Omicron}({lambda}{sup 3}) diagrams where the intermediate state that goes on-shell has a different visible baryon number than the final state visible baryon number. Models in which the correct baryon number is generated with freeze-in as the dominant source of abundance, typically require {lambda} {approx}> 10{sup -6} and m{sub bath} {approx}> TeV. m{sub bath} is the mass of the visible particle which communicates with the hidden sector. The lower window is potentially observable at the LHC.

  18. A Fast Hadron Freeze-out Generator

    E-print Network

    N. S. Amelin; R. Lednicky; T. A. Pocheptsov; I. P. Lokhtin; L. V. Malinina; A. M. Snigirev; Iu. A. Karpenko; Yu. M. Sinyukov

    2006-10-13

    We have developed a fast Monte Carlo procedure of hadron generation allowing one to study and analyze various observables for stable hadrons and hadron resonances produced in ultra-relativistic heavy ion collisions. Particle multiplicities are determined based on the concept of chemical freeze-out. Particles can be generated on the chemical or thermal freeze-out hypersurface represented by a parameterization or a numerical solution of relativistic hydrodynamics with given initial conditions and equation of state. Besides standard space-like sectors associated with the volume decay, the hypersurface may also include non-space-like sectors related to the emission from the surface of expanding system. For comparison with other models and experimental data we demonstrate the results based on the standard parameterizations of the hadron freeze-out hypersurface and flow velocity profile under the assumption of a common chemical and thermal freeze-out. The C++ generator code is written under the ROOT framework and is available for public use at http://uhkm.jinr.ru/.

  19. Preservation of corynebacteriophages by freeze-drying

    PubMed Central

    Carne, H. R.; Greaves, R. I. N.

    1974-01-01

    A method of freeze-drying is described by which the activity of a series of eorynebacteriophages was maintained over a test period of 30 months, whereas some of these strains became inactive if stored as liquid filtered lysates at 4° C., or frozen and held at -25° C. PMID:4602040

  20. Freezing of Triangulations J.-P. Kownacki

    E-print Network

    Paris-Sud XI, Université de

    E-mail : kownacki@ptm.u-cergy.fr Abstract Zero temperature dynamics of two dimensional into clusters of same topological charge. It is conjectured that freezing is related to high temperature structure of baby universes. Published in Eur. Phys. J B 38, 485-494 (2004) 1 #12;1 Introduction Two

  1. Freeze verification: time for a fresh approach

    Microsoft Academic Search

    Paine

    1983-01-01

    The administration's claim that some elements of a comprehensive nuclear freeze are unverifiable does not specify the nature of those elements and whether they represent a real threat to national security if we trusted the USSR to comply. The author contends that clandestine development of new weapons will have little strategic effect since both sides already have total destructive power.

  2. FREEZE-FRAME: Fast Action Stress Relief.

    ERIC Educational Resources Information Center

    Childre, Doc Lew

    Recent scientific research has proven that we can, not only manage our stress, we can even prevent it. Ways to achieve stress management are presented in this book. It details a method called FREEZE-FRAME, a process in which individuals mentally stop the chaos that surrounds them and then calmly contemplate their situation. The text opens with an…

  3. Depressive Störungen: Major Depression und Dysthymie

    Microsoft Academic Search

    K. Beesdo-Baum; H.-U. Wittchen

    \\u000a Fast jeder Mensch erlebt hin und wieder vereinzelte depressive Symptome wie Traurigkeit, Niedergeschlagenheit oder Antriebslosigkeit, z. B. im Zusammenhang mit belastenden Ereignissen, Erkrankungen\\u000a oder sozialen Stresssituationen. Von einer behandlungsbedürftigen depressiven Störung spricht man allerdings erst, wenn die Symptome eine bestimmte Zeitdauer, Persistenz und Intensität überschreiten. Als Kernmerkmale\\u000a einer Major Depression, als häufigste Form depressiver Störungen, gelten über mindestens 2 Wochen

  4. Deliquesence and freezing of stratospheric aerosol observed by balloonborne backscattersondes

    SciTech Connect

    Larsen, N.; Knudsen, B. [Danish Meterological Institute, Copenhagen (Denmark)] [Danish Meterological Institute, Copenhagen (Denmark); Rosen, J.M. [Univ. of Wyoming, Laramie, WY (United States)] [and others] [Univ. of Wyoming, Laramie, WY (United States); and others

    1995-05-15

    Stratospheric sulfate aerosols, originating from the Mt. Pinatubo volcanic eruption, have been observed during three winters in the Arctic by balloonborne backscattersondes. A measured color index, defined as the quotient between the aerosol backscatter ratios at wavelengths 940 and 480 nm, provides information of the size of the observed particles. The effects of liquid particle growth, by water vapor uptake, clearly show up as changes in the color index, whereas measurements on other days indicate the particles to be frozen. Air parcel trajectories have been calculated, providing the temperature history of the observed particles. Evidences appear of a temperature hysteresis in the freezing and melting cycle of the aerosol, indicating melting temperatures around 215-220 K in good agreement with laboratory measurements, and freezing of the particles within less than 5 K above the ice frost point. The changes in color index of the liquid particles are in good agreement with predictions from theoretical model calculations of growth by water vapor uptake. 13 refs., 5 figs., 1 tab.

  5. The depressive situation

    PubMed Central

    A. Jacobs, Kerrin

    2013-01-01

    From a naturalistic perspective on mental illness, depression is often described in terms of biological dysfunctions, while a normative perspective emphasizes the lived experience of depression as a harmful condition. The paper relates a conceptual analysis of “depressive situation” to an analysis of the lived experience of depression. As such, it predominantly aims to specify depression as a harmful condition in lights of normative perspective on mental disorder, but partially refers to empirical research, i.e., naturalistic perspective on depression, to exemplarily stress on the methodological merits and limits of relating phenomenological considerations closer to empirical research. The depressive situation is further specified with an examination of the evaluative dynamics by which individuals meaningfully relate to themselves, others and the world. These evaluative dynamics emerge out of the interplay of pre-reflective and reflective processes, which are significantly altered in depression. Such alterations of the evaluative structure are inextricably intertwined with significant distortions of practical sense in depression. From a phenomenological perspective, these distortions of practical sense show in characteristic experiences of evaluative incoherence and impairments of agency. Finally, this paper focuses on an examination of “evaluative incapacity,” which has the integrative potential to capture a range of typical changes of meaningful relatedness that determine the depressive situation. PMID:23882238

  6. The Inventory to Diagnose Depression (IDD): A Self-Report Scale to Diagnose Major Depressive Disorder

    Microsoft Academic Search

    Mark Zimmerman; William Coryell

    1987-01-01

    The Inventory to Diagnose Depression (IDD) is a 22-item self-report scale designed to diagnose major depressive disorder (MDD) according to Diagnostic and Statistical Manual of Mental Disorders (DSM-III;American Psychiatric Association, 1980) criteria. Three hundred ninety-eight relatives of psychiatric patients and normal controls completed the IDD and were interviewed with the Diagnostic Interview Scale (DIS). The point prevalence of MDD was

  7. Effects of freezing on plant mesophyll cells.

    PubMed

    Krause, G H; Grafflage, S; Rumich-Bayer, S; Somersalo, S

    1988-01-01

    Freezing and thawing of leaves of herbaceous plants leads to damage when the freezing temperature falls below a certain tolerance limit, which depends on the plant species and state of acclimation. Such damage is expressed as an irreversible inhibition of photosynthesis observed after thawing. In frost-damaged leaves the capacity of photosynthetic reactions of the thylakoid membranes is impaired. Particularly, the water-oxidation system, photosystems II and I are inhibited. However, it appears that CO2 assimilation is more readily affected by freezing stress than the activity of the thylakoids. The inhibition of CO2 fixation seen in initial stages of damage seems to be independent of thylakoid inactivation. This can be shown by chlorophyll fluorescence analysis made simultaneously with measurement of CO2 assimilation. Fluorescence emission by leaves is strongly influenced by carbon assimilation activity, namely via the redox state of the photosystem II electron acceptor QA (QA-dependent quenching) and via energization of the thylakoid membranes depending on the transthylakoid proton gradient (energy-dependent quenching). Resolution of these components of fluorescence changes provides insight into alterations of the CO2 fixing capacity of the chloroplasts and properties of the thylakoids. The effects of freezing and thawing were studied in detail with isolated mesophyll protoplasts prepared from both non-hardened and cold-acclimated plants of Valerianella locusta L. Freezing damage was characterized by various parameters such as plasma membrane integrity, photosynthetic CO2 assimilation, chlorophyll fluorescence emission and activities of thylakoids isolated from the protoplasts. All tests indicated a substantially increased frost tolerance of protoplasts obtained from cold-acclimated as compared to non-hardened leaves. CO2 assimilation and related fluorescence changes were the most freezing-sensitive parameters in both types of protoplasts. Inactivation of CO2 assimilation was correlated neither to the disintegration of the plasma membrane nor to inactivation of the thylakoids. Experimental data indicate that freeze-thaw treatment affected the light-regulated enzymes of the carbon reduction cycle, such as fructose-1,6-bisphosphatase, sedoheptulose-1,7-bisphosphatase and ribulose-1,5-bisphosphate carboxylase. Inhibition of light-activation of these enzymes may be based on altered properties of the chloroplast envelope. PMID:3077862

  8. Attributional processing style differences in depressed and nondepressed individuals

    Microsoft Academic Search

    Daniele Kammer

    1984-01-01

    A series of four studies used different measures to assess the amount of attributional processing following failure and success. It was found that, from an actor's point of view, relatively depressed students consistently differed from relatively nondepressed students in the amount of their attributional processing. The depressed individuals reported more attributions for both hypothetical and real failure, compared to the

  9. Detecting depression among adolescents in Santiago, Chile: sex differences

    PubMed Central

    2013-01-01

    Background Depression among adolescents is common but most cases go undetected. Brief questionnaires offer an opportunity to identify probable cases but properly validated cut-off points are often unavailable, especially in non-western countries. Sex differences in the prevalence of depression become marked in adolescence and this needs to be accounted when establishing cut-off points. Method This study involved adolescents attending secondary state schools in Santiago, Chile. We compared the self-reported Beck Depression Inventory-II with a psychiatric interview to ascertain diagnosis. General psychometric features were estimated before establishing the criterion validity of the BDI-II. Results The BDI-II showed good psychometric properties with good internal consistency, a clear unidimensional factorial structure, and good capacity to discriminate between cases and non-cases of depression. Optimal cut-off points to establish caseness for depression were much higher for girls than boys. Sex discrepancies were primarily explained by differences in scores among those with depression rather than among those without depression. Conclusions It is essential to validate scales with the populations intended to be used with. Sex differences are often ignored when applying cut-off points, leading to substantial misclassification. Early detection of depression is essential if we think that early intervention is a clinically important goal. PMID:23617306

  10. Examining the world of the depressed: do depressed people prefer others who are depressed?

    PubMed

    Rosenblatt, A; Greenberg, J

    1991-04-01

    Two studies were conducted to examine the interpersonal world of the depressed person. In Study 1, depression levels and perceptions of depressed and nondepressed people and their best friend were assessed to test the hypothesis that depressed Ss have best friends who are themselves more depressed than the best friends of nondepressed Ss. The hypothesis was confirmed, suggesting that depressed persons may prefer others who also tend toward depression. To examine this possibility, in Study 2 depressed and nondepressed college students spoke with one another in either depressed-depressed, nondepressed-depressed, or nondepressed-nondepressed pairs. It was found that depressed Ss felt worse than nondepressed Ss after speaking with nondepressed targets, but not after speaking with depressed targets. There were no differences in liking or in perceived similarity between the groups. Implications for the social world of the depressed person are discussed. PMID:2037970

  11. Effect of process conditions on recovery of protein activity after freezing and freeze-drying

    Microsoft Academic Search

    Shan Jiang; Steven L Nail

    1998-01-01

    The objective of this research was to gain a better understanding of the degree to which recovery of activity of model proteins after freeze-drying can be maximized by manipulation of freeze-dry process conditions in the absence of protective solutes. Catalase, ?-galactosidase and lactate dehydrogenase (LDH) were used as model proteins. All of the three proteins exhibited a concentration-dependent loss of

  12. Original article Spray-freeze-drying of whey proteins

    E-print Network

    Paris-Sud XI, Université de

    Original article Spray-freeze-drying of whey proteins at sub-atmospheric pressures Chinnaswamy February 2010 Published online 30 March 2010 Abstract ­ Spray-freeze-drying (SFD) involves spraying a solution into a cold medium, and freeze- drying the resultant frozen particles, which can be performed

  13. Modification of physical properties of freeze-dried rice

    NASA Technical Reports Server (NTRS)

    Huber, C. S.

    1971-01-01

    Freeze cycling process consists of alternately freezing and thawing precooked rice for two cycles, rice is then frozen and freeze-dehydrated in vacuum sufficient to remove water from rice by sublimitation. Process modifies rice grain structure and porosity, enabling complete rehydration in one minute in hot water.

  14. Genetics of winter wheat response to two freezing treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The inheritance of the ability of winter wheat plants to survive two kinds of freezing stress was investigated in a five-parent diallel cross. Plants were acclimated at +4°C for 5 wks and frozen with or without a –3°C, 16-hour pre-freezing (PF) period prior to freezing to damaging temperatures. The ...

  15. Damage by Early Autumn Freeze Varies with Pecan Cultivar

    Microsoft Academic Search

    Michael W. Smith

    Pecan (Carya illinoinensis (Wangenh.) C. Koch.) trees were injured by freezing temperatures in Oct. 2000, occurring about 4 weeks before the average first freeze and 6 weeks before the normal killing freeze (less than or equal to -2 °C). Nonbearing and bearing cultivars were rated for injury at four sites the following May. Nonbearing cultivars with little or no damage

  16. Interdecadal changes in seasonal freeze and thaw depths in Russia

    Microsoft Academic Search

    Oliver W. Frauenfeld; Tingjun Zhang; Roger G. Barry; David Gilichinsky

    2004-01-01

    Seasonal freezing and thawing processes in cold regions play a major role in ecosystem diversity, productivity, and the Arctic hydrological system. Long-term changes in seasonal freeze and thaw depths are also important indicators of climate change. Only sparse historical measurements of seasonal freeze and thaw depths are available for permafrost and seasonally frozen ground regions. Using mean monthly soil temperature

  17. Foliar applied urea improves freezing protection to avocado and peach

    Microsoft Academic Search

    S. Zilkah; Z. Wiesmann; I. Klein; I. David

    1996-01-01

    The effect of foliar applied urea on freeze hardiness was evaluated under orchard and laboratory conditions. Freezing injury and senescence of avocado (Persea americana Mill.) cv. ‘Hass’ leaves in the orchard was inversely correlated to N content. Three foliar applications of 2% low-biuret urea caused a 26% nitrogen enrichment of leaves. Consequently, leaf freezing hardiness was increased and senescence retarded.

  18. The parenchymal reaction of the kidney after local freezing

    Microsoft Academic Search

    H. Breining; B. Helpap; A. Minderjahn; S. Lymberopoulos

    1974-01-01

    Histological and autoradiographic studies were performed to investigate the reparative processes during wound healing in kidneys after local freezing. 12h after freezing (-186°C, 30 sec) the cryonecrosis is fully developed. After the 5th postoperative day the cryonecrotic area shows a pronounced calcification of necrotic tubules. 30 days after freezing the reparation of the cryolesion in the kidney results in a

  19. VISUALIZATION OF FREEZING PROGRESSION IN TURFGRASSES USING INFRARED VIDEO THERMOGRAPHY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Freezing injury can be a significant problem in turfgrasses. Understanding how freezing develops and ramifies throughout the plant could assist in the development of improved management or screening processes for cultivar improvemen. The development of freezing injury is not well understand due pa...

  20. Objective video quality assessment method for freeze distortion based on freeze aggregation

    NASA Astrophysics Data System (ADS)

    Watanabe, Keishiro; Okamoto, Jun; Kurita, Takaaki

    2006-01-01

    With the development of the broadband network, video communications such as videophone, video distribution, and IPTV services are beginning to become common. In order to provide these services appropriately, we must manage them based on subjective video quality, in addition to designing a network system based on it. Currently, subjective quality assessment is the main method used to quantify video quality. However, it is time-consuming and expensive. Therefore, we need an objective quality assessment technology that can estimate video quality from video characteristics effectively. Video degradation can be categorized into two types: spatial and temporal. Objective quality assessment methods for spatial degradation have been studied extensively, but methods for temporal degradation have hardly been examined even though it occurs frequently due to network degradation and has a large impact on subjective quality. In this paper, we propose an objective quality assessment method for temporal degradation. Our approach is to aggregate multiple freeze distortions into an equivalent freeze distortion and then derive the objective video quality from the equivalent freeze distortion. Specifically, our method considers the total length of all freeze distortions in a video sequence as the length of the equivalent single freeze distortion. In addition, we propose a method using the perceptual characteristics of short freeze distortions. We verified that our method can estimate the objective video quality well within the deviation of subjective video quality.

  1. Ultrastructure of the frog retina after high-pressure freezing and freeze substitution.

    PubMed

    Wilson, M T; Farmer, M A; Karwoski, C J

    1998-03-01

    In many types of tissue, high-pressure freezing (HPF), followed by freeze substitution, can produce excellent ultrastructural preservation at depths over 10 times that obtained by other cryofixation techniques. However, in the case of neural tissue, the benefits of HPF have not been realized. In the present study, isolated frog (Rana pipiens) retina was sliced at a thickness of 150 or 350 microns, rapidly frozen in a Balzers HPM 010 high-pressure freezer, and freeze substituted with 1% OsO4 and 0.1% tannic acid in acetone. Specially designed HPF chambers and specific freezing media (35% high-MW dextran for 150-micron slices or 15% low-MW dextran for 350-micron slices) were required for adequate freezing. The quality of preservation after HPF was excellent throughout the retina in both the 150- and 350-micron slices, compared with chemically fixed slices. Specifically, HPF resulted in better preserved cellular, mitochondrial and nuclear membranes in all retinal layers. This is the first study to successfully cryofix all of the layers of the retina. The increased depths of adequate freezing achieved by HPF should facilitate various ultrastructural studies of retina, as well as of other CNS tissues, where preservation approaching that of the 'native' state is required. PMID:9588021

  2. Exact theory of freeze out

    E-print Network

    Mirco Cannoni

    2015-03-05

    We show that the standard theory of thermal production and chemical decoupling of WIMPs is incomplete. The hypothesis that WIMPs are produced and decouple from a thermal bath implies that the rate equation the bath particles interacting with the WIMPs is an algebraic equation that constraints the actual WIMPs abundance to have a precise analytical form down to the temperature $x_\\ast=m_\\chi /T_\\ast$. The point $x_\\ast$, which coincides with the stationary point of the equation for the quantity $\\Delta= Y-Y_0$, is where the maximum departure of the WIMPs abundance $Y$ from the thermal value $Y_0$ is reached. For each mass $m_\\chi$ and total annihilation cross section $\\langle \\sigma_\\text{ann}v_\\text{r}\\rangle$, the temperature $x_\\ast$ and the actual WIMPs abundance $Y(x_\\ast)$ are exactly known. This value provides the true initial condition for the usual differential equation that have to be integrated in the interval $x\\ge x_\\ast$. The matching of the two abundances at $x_\\ast$ is continuous and differentiable. The dependence of the present relic abundance on the abundance at an intermediate temperature is an exact result. The exact theory suggests a new analytical approximation that furnishes the relic abundance accurate at the level of $1\\%-2\\%$ in the case of $S$-wave and $P$-wave scattering cross sections. We conclude the paper studying the evolution of the WIMPs chemical potential and the entropy production using methods of non equilibrium thermodynamics.

  3. NIM Realization of the Gallium Triple Point

    Microsoft Academic Search

    Yan Xiaoke; Qiu Ping; Duan Yuning; Qu Yongmei

    2003-01-01

    In the last three years (1999 to 2001), the gallium triple-point cell has been successfully developed, and much corresponding research has been carried out at the National Institute of Metrology (NIM), Beijing, China. This paper presents the cell design, apparatus and procedure for realizing the gallium triple point, and presents studies on the different freezing methods. The reproducibility is 0.03

  4. Control of pore channel size during freeze casting of porous YSZ ceramics with unidirectionally aligned channels using different freezing temperatures

    Microsoft Academic Search

    Liangfa Hu; Chang-An Wang; Yong Huang; Chencheng Sun; Sheng Lu; Zijun Hu

    2010-01-01

    Porous yttria-stabilized zirconia (YSZ) ceramics with unidirectionally aligned pore channels were prepared by freezing YSZ\\/tert-butyl alcohol (TBA) slurry under different freezing temperatures of ?30, ?78 and ?196°C, respectively. After removing the frozen TBA via freeze-drying in vacuum at ?50°C, the green samples were sintered at 1450°C for 2h in air. The results showed that the freezing temperature significantly influenced microstructure

  5. Embodied intervention reduce depression

    NASA Astrophysics Data System (ADS)

    Song, Dong-Qing; Bi, Xin; Fu, Ying

    2011-10-01

    To investigate the difference of the selected-rate of undergraduates' depression with respect to time, gender and scales and the intervention effect of embodied exercise, 201 Undergraduates were measured with Self-Rating Depression Scale and Beck Depression Inventory (BDI).The result shows there are significant difference of the selected-rates of undergraduates' depression resulted from long-time interval rather than from short-time interval and gender. After the intervention, the selected-rates are decreased and no significant difference has been found between the embodied groups and the controlled group. Only the embodied groups maintain the better effects of the intervention in the tracking. Also the result shows that only the participants of embodied groups obtain more positive emotional experience. We conclude that there is significant difference of selected-rate of undergraduates' depression on scales, and the embodied exercise can effectively reduce undergraduate's depression.

  6. Diabetes and depression.

    PubMed

    Holt, Richard I G; de Groot, Mary; Golden, Sherita Hill

    2014-06-01

    Diabetes and depression occur together approximately twice as frequently as would be predicted by chance alone. Comorbid diabetes and depression are a major clinical challenge as the outcomes of both conditions are worsened by the other. Although the psychological burden of diabetes may contribute to depression, this explanation does not fully explain the relationship between these 2 conditions. Both conditions may be driven by shared underlying biological and behavioral mechanisms, such as hypothalamic-pituitary-adrenal axis activation, inflammation, sleep disturbance, inactive lifestyle, poor dietary habits, and environmental and cultural risk factors. Depression is frequently missed in people with diabetes despite effective screening tools being available. Both psychological interventions and antidepressants are effective in treating depressive symptoms in people with diabetes but have mixed effects on glycemic control. Clear care pathways involving a multidisciplinary team are needed to obtain optimal medical and psychiatric outcomes for people with comorbid diabetes and depression. PMID:24743941

  7. Diabetes and Depression

    PubMed Central

    de Groot, Mary; Golden, Sherita Hill

    2015-01-01

    Diabetes and depression occur together approximately twice as frequently as would be predicted by chance alone. Comorbid diabetes and depression are a major clinical challenge as the outcomes of both conditions are worsened by the other. Although the psychological burden of diabetes may contribute to depression, this explanation does not fully explain the relationship between these 2 conditions. Both conditions may be driven by shared underlying biological and behavioral mechanisms, such as hypothalamic-pituitary-adrenal axis activation, inflammation, sleep disturbance, inactive lifestyle, poor dietary habits, and environmental and cultural risk factors. Depression is frequently missed in people with diabetes despite effective screening tools being available. Both psychological interventions and antidepressants are effective in treating depressive symptoms in people with diabetes but have mixed effects on glycemic control. Clear care pathways involving a multidisciplinary team are needed to obtain optimal medical and psychiatric outcomes for people with comorbid diabetes and depression. PMID:24743941

  8. Ethiopathogenesis of Depressive Disorders

    PubMed Central

    Pasquini, M; Berardelli, I; Biondi, M

    2014-01-01

    Etiology of depressive disorders is still unknown. Several factors are involved in its pathophysiology such as neurotransmitters and neuroendocrine alterations, genetics, life events and their appraisal. Some of these components are strictly linked. Subjects with a family member affected by mood disorders are more prone to suffer from depressive disorders. It is also true that receiving feedbacks of indifference or neglect during childhood from one parent who suffer from depression may represent a factor of vulnerability. Indeed, reaction to a specific negative event may determine an increased allostasis which lead to a depressive episode. Thus, a psychological cause does not exclude a neurobiological cascade. Whereas in other cases recurrent depressive episodes appear in absence of any negative life event. This review provides a set of data regarding the current etiopathogenesis models of depression, with a particular attention to the neurobiological correlates and vulnerability factors. PMID:25614753

  9. Depression-like deficits in rats improved by subchronic modafinil

    Microsoft Academic Search

    Ralf Regenthal; Holger Koch; Christian Köhler; Rainer Preiss; Ute Krügel

    2009-01-01

    Rationale  Attentional and sensorimotor gating deficits in human depression are observed as residual symptoms irrespective of antidepressant\\u000a treatment. Clinical studies point to a benefit of modafinil in depression. No data are available on modafinil effects in depression-like\\u000a animal models.\\u000a \\u000a \\u000a \\u000a Objectives  We investigated effects of modafinil on attention and sensorimotor gating after subchronic treatment during a restraint stress\\u000a protocol inducing depression-like changes in

  10. Depression and the Gifted Child.

    ERIC Educational Resources Information Center

    Little, Cindy

    2002-01-01

    This article discusses the incidence of depression and signs of depression in gifted children, including perfectionism, emotional sensitivity, existential depression, and a history of depression in the family. A list of questions to consider regarding possible signs of depression in children is provided. (Contains references.) (CR)

  11. Predictors of Persistence After a Positive Depression Screen Among Adolescents

    PubMed Central

    McCauley, Elizabeth; McCarty, Carolyn A.; Grossman, David C.; Myaing, Mon; Zhou, Chuan; Richards, Julie; Rockhill, Carol; Katon, Wayne

    2012-01-01

    OBJECTIVE: To examine predictors of depression persistence after a positive screening test to inform management protocols for screened youth. METHODS: We conducted a cohort study of 444 youth (aged 13–17 years) from a large health care delivery system. Youth with depressive symptoms, based on a 2-item depression screen, were oversampled for the baseline interview. Baseline assessments included the Patient Health Questionnaire 9-item (PHQ-9) depression screen as well as clinical factors that were hypothesized to influence depression persistence (family history of depression, functional impairment, perceived social support, anxiety symptoms, externalizing symptoms, and medical comorbidity). Logistic regression analysis was used to examine factors associated with the persistence of depression at 6 months postbaseline. RESULTS: Of 113 youth with a positive baseline screen (PHQ-9 ?11), 47% and 35% continued to be positive at 6-week and 6-month follow-up, respectively. After controlling for treatment status, only 2 factors were significantly associated with depression persistence at 6 months: baseline depressive symptom score and continuing to have a positive screen at 6 weeks. For each 1-point increase on the PHQ-9 score at baseline, youth had a 16% increased odds of continuing to be depressed at 6 months (odds ratio: 1.16, 95% confidence interval: 1.01–1.34). Youth who continued to screen positive 6 weeks later had almost 3 times the odds of being depressed at 6 months (odds ratio: 2.89, 95% confidence interval: 1.09–7.61). CONCLUSIONS: Depressive symptom severity at presentation and continued symptoms at 6 weeks postscreening are the strongest predictors of depression persistence. Patients with high depressive symptom scores and continued symptoms at 6 weeks should receive active treatment. PMID:23166342

  12. Neurobiology of Depression

    Microsoft Academic Search

    Eric J. Nestler; Michel Barrot; Ralph J. DiLeone; Amelia J. Eisch; Stephen J. Gold; Lisa M. Monteggia

    2002-01-01

    Current treatments for depression are inadequate for many individuals, and progress in understanding the neurobiology of depression is slow. Several promising hypotheses of depression and antidepressant action have been formulated recently. These hypotheses are based largely on dysregulation of the hypothalamic-pituitary-adrenal axis and hippocampus and implicate corticotropin-releasing factor, glucocorticoids, brain-derived neurotrophic factor, and CREB. Recent work has looked beyond hippocampus

  13. Cognitive deficits in depression 

    E-print Network

    Haines, Mary Ellen

    1993-01-01

    used to detect cognitive deficits may not have tested for the types of impairments that occur specifically for individuals with mild depression; 3) perhaps due to the high rate of comorbidity of anxiety and depression, studies that have found... cognitive deficits in depression have actually tapped cognitive deficits due to a concomitant anxiety disorder; or, 4) the demanding nature of the PASAT may have elicited test anxiety, a transitory state of anxiety that results in decreased performance...

  14. Effects of Freeze\\/Thaw Index, Air Temperature, and Snow Cover on Seasonal Freeze and Thaw Depths in Russia

    Microsoft Academic Search

    O. W. Frauenfeld; T. Zhang; R. G. Barry; D. Gilichinsky; A. J. Etringer

    2003-01-01

    Seasonal freezing and thawing processes in cold regions play an exceedingly important role in ecosystem diversity, productivity, and the Arctic hydrological system in general. Long-term changes in seasonal freeze and thaw depths are also important indicators of climate change. Only sparse observational measurements of seasonal freeze and thaw depths are available in permafrost and seasonally frozen ground regions. However, soil

  15. Cognitive Aspects of Depression

    PubMed Central

    Joormann, Jutta; Gotlib, Ian H.

    2012-01-01

    Depression is a prevalent and impairing psychiatric disorder that affects how we feel and how we think about ourselves and the world around us. Cognitive theories of depression have long posited that various thought processes are involved in the development, maintenance, and recurrence of depressive episodes. Contemporary research has utilized experimental procedures to examine cognitive processes in depressed individuals as well as the nature of the relation of these processes to the emotion dysregulation that is central to the disorder. For example, investigators have assessed the ways in which depression alters aspects of information processing, including attention and perception, interpretation, and memory processes; this research has generated relatively consistent findings. In addition, researchers have attempted to identify and elucidate the cognitive mechanisms that may link these biases in information processing to emotion dysregulation in depression. These mechanisms include inhibitory processes and deficits in working memory, ruminative responses to negative mood states, and the inability to use positive and rewarding stimuli to regulate negative mood. Results of these investigations converge on the formulation that depression is associated with increased elaboration of negative information, difficulties in cognitive control when processing this information, and difficulties disengaging from this information. Research examining cognitive aspects of depression not only enhances our understanding of this common and costly disorder, but also has implications for the treatment of depression and for future investigations of the biological foundations of this disorder. PMID:23240069

  16. Heart failure and depression.

    PubMed

    Newhouse, Amy; Jiang, Wei

    2014-04-01

    Depression frequently accompanies heart failure and has been linked with increased morbidity and mortality. Patients with heart failure who have depression have more somatic symptoms, hospitalizations, increased financial burden, and poorer quality of life. Furthermore, depression has been shown to be an independent predictor of future cardiac events in patients with heart failure, regardless of disease severity, making it worthwhile to consider among other cardiac risk factors, such as diabetes and smoking. This article summarizes the trials assessing the treatment of depression in heart failure and provides an algorithm for approaching these patients. PMID:24656106

  17. Recognition of Depression in the Primary School Child. Selected Papers, Number 56.

    ERIC Educational Resources Information Center

    Schick, Tom

    Real depression in children can manifest itself in many ways. Every human being is somewhat different and consequently distress signals and breaking points do not always imitate each other. What remains constant is the internal emotional desert and emptiness. Depression is not just feeling sad or lethargic. Depression is a state in which…

  18. Depression in China: Integrating Developmental Psychopathology and Cultural-Clinical Psychology

    ERIC Educational Resources Information Center

    Ryder, Andrew G.; Sun, Jiahong; Zhu, Xiongzhao; Yao, Shuqiao; Chentsova-Dutton, Yulia E.

    2012-01-01

    With a starting point in John Abela's groundbreaking developmental psychopathology research on adolescent depression in China, we aimed to review the state of the literature on Chinese depression across the lifespan. We began with Dr. Abela's published studies relevant to depression in China and our own research with adults before turning to the…

  19. Bioactive compounds of grapefruit (Citrus paradisi Cv. Rio Red) respond differently to postharvest irradiation, storage, and freeze drying.

    PubMed

    Vanamala, Jairam; Cobb, Greg; Turner, Nancy D; Lupton, Joanne R; Yoo, Kil Sun; Pike, Leonard M; Patil, Bhimanagouda S

    2005-05-18

    In the present study, the effect of irradiation, storage, and freeze drying on grapefruit bioactive compounds was investigated. Grapefruits were exposed to one of two irradiation doses: 0 (control) or 300 Gy (137Cs, a proposed treatment against fruit flies) and then stored for up to 6 days. At the last storage time point (6 days after harvest), grapefruit pulp from control and irradiated fruits was freeze-dried. Bioactive compounds were extracted from Rio Red grapefruit pulp and analyzed with reverse phase liquid chromatography while volatile compounds were analyzed using gas chromatography. Freeze-dried pulp from irradiated fruits had a higher (P < or = 0.05) flavonoid content (naringin and narirutin) as compared to the freeze-dried pulp from the control fruits. Freeze-drying treatment reduced (P < or = 0.05) the lycopene content, but the reduction (P < or = 0.05) in beta-carotene content occurred only in the control fruit. Reduction in d-limonene and myrcene was observed in the irradiated fruits at 6 days after harvest and in the freeze-dried samples. These results warrant testing of the effect of postharvest treatments and processing on bioactive compounds in functional systems as they have varied effects on different bioactive compounds of grapefruit. PMID:15884827

  20. Exotic Freezing of Response in Quantum Many-Body System

    E-print Network

    Arnab Das

    2010-11-01

    We show that when a quantum many-body system is subjected to coherent periodic driving, the response may exhibit exotic freezing behavior in high driving frequency ($\\omega$) regime. In a periodically driven classical thermodynamic system, freezing at high $\\omega$ occurs when $1/\\omega$ is much smaller than the characteristic relaxation time of the system, and hence the freezing always increases there as $\\omega$ is increased. Here, in the contrary, we see surprising non-monotonic freezing behavior of the response with $\\omega$, showing curious peak-valley structure. Quite interestingly, the entire system tends to freeze almost absolutely (the freezing peaks) when driven with a certain combination of driving parameters values (amplitude and $\\omega$) due to coherent suppression of dynamics of the quantum many-body modes, which has no classical analog. We demonstrate this new freezing phenomenon analytically (supported by large-scale numerics) for a general class of integrable quantum spin systems.

  1. Depression in Children and Adolescents

    MedlinePLUS

    ... Us Home > Health & Education > Mental Health Information > Depression Depression in Children and Adolescents More Only in the ... increased risk for suicide . Share Science News About Depression Disorders Share Same Gene Pathways Rapid Mood Lifter ...

  2. Freeze-out parameters: lattice meets experiment

    E-print Network

    S. Borsanyi; Z. Fodor; S. D. Katz; S. Krieg; C. Ratti; K. K. Szabo

    2013-05-22

    We present our results for ratios of higher order fluctuations of electric charge as functions of the temperature. These results are obtained in a system of 2+1 quark flavors at physical quark masses and continuum extrapolated. We compare them to preliminary data on higher order moments of the net electric charge distribution from the STAR collaboration. This allows us to determine the freeze-out temperature and chemical potential from first principles. We also show continuum-extrapolated results for ratios of higher order fluctuations of baryon number. These will allow to test the consistency of the approach, by comparing them to the corresponding experimental data (once they become available) and thus extracting the freeze-out parameters in an independent way.

  3. Activities on Facebook Reveal the Depressive State of Users

    PubMed Central

    Kwak, Jinah

    2013-01-01

    Background As online social media have become prominent, much effort has been spent on identifying users with depressive symptoms in order to aim at early diagnosis, treatment, and even prevention by using various online social media. In this paper, we focused on Facebook to discern any correlations between the platform’s features and users’ depressive symptoms. This work may be helpful in trying to reach and detect large numbers of depressed individuals more easily. Objective Our goal was to develop a Web application and identify depressive symptom–related features from users of Facebook, a popular social networking platform. Methods 55 Facebook users (male=40, female=15, mean age 24.43, SD 3.90) were recruited through advertisement fliers distributed to students in a large university in Korea. Using EmotionDiary, the Facebook application we developed, we evaluated depressive symptoms using the Center for Epidemiological Studies-Depression (CES-D) scale. We also provided tips and facts about depression to participants and measured their responses using EmotionDiary. To identify the Facebook features related to depression, correlation analyses were performed between CES-D and participants’ responses to tips and facts or Facebook social features. Last, we interviewed depressed participants (CES-D?25) to assess their depressive symptoms by a psychiatrist. Results Facebook activities had predictive power in distinguishing depressed and nondepressed individuals. Participants’ response to tips and facts, which can be explained by the number of app tips viewed and app points, had a positive correlation (P=.04 for both cases), whereas the number of friends and location tags had a negative correlation with the CES-D scale (P=.08 and P=.045 respectively). Furthermore, in finding group differences in Facebook social activities, app tips viewed and app points resulted in significant differences (P=.01 and P=.03 respectively) between probably depressed and nondepressed individuals. Conclusions Our results using EmotionDiary demonstrated that the more depressed one is, the more one will read tips and facts about depression. We also confirmed depressed individuals had significantly fewer interactions with others (eg, decreased number of friends and location tagging). Our app, EmotionDiary, can successfully evaluate depressive symptoms as well as provide useful tips and facts to users. These results open the door for examining Facebook activities to identify depressed individuals. We aim to conduct the experiment in multiple cultures as well. PMID:24084314

  4. The ammonia freeze explosion (AFEX) process

    Microsoft Academic Search

    Mark T. Holtzapple; Jae-Hoon Jun; Ganesh Ashok; Srinivas L. Patibandla; Bruce E. Dale

    1991-01-01

    The Ammonia Freeze Explosion (AFEX) process treats lignocellulose with high-pressure liquid ammonia, and then explosively\\u000a releases the pressure. The combined chemical effect (cellulose decrystallization) and physical effect (increased accessible\\u000a surface area) dramatically increase lignocellulose susceptibility to enzymatic attack. There are many adjustable parameters\\u000a in the AFEX process: ammonia loading, water loading, temperature, time, blowdown pressure, and number of treatments. The

  5. Preparation of mesoporous carbon by freeze drying

    Microsoft Academic Search

    H. Tamon; H. Ishizaka; T. Yamamoto; T. Suzuki

    1999-01-01

    Resorcinol–formaldehyde (RF) cryogels were synthesized by sol-gel polycondensation of resorcinol with formaldehyde and freeze drying with t-butanol. The cryogels were characterized by nitrogen adsorption and density measurements. Their porous properties were compared with those of RF aerogels prepared by supercritical drying with carbon dioxide. RF cryogels were mesoporous materials with large mesopore volumes >0.58 cm3\\/g. Although surface areas and mesopore

  6. An Improved Cryogen for Plunge Freezing

    PubMed Central

    Tivol, William F.; Briegel, Ariane; Jensen, Grant J.

    2011-01-01

    The use of an alkane mixture that remains liquid at 77 K to freeze specimens has advantages over the use of a pure alkane that is solid at 77 K. It was found that a mixture of methane and ethane did not give a cooling rate adequate to produce vitreous ice, but a mixture of propane and ethane did result in vitreous ice. Furthermore, the latter mixture produced less damage to specimens mounted on a very thin, fragile holey carbon substrate. PMID:18793481

  7. Freeze Thaw Durability of Modern Concrete Mixtures

    E-print Network

    Techniques #12;Current Measuring Techniques PCA photo ASTM C 231 PCA photo ASTM C 173 ASTM C 138 #12;Current Measuring Techniques PCA photo ASTM C 231 PCA photo ASTM C 173 ASTM C 138 These only measure volume!!! #12;0.0 0.1 0.2 0.3 0.4 0 2 4 6 8 10 air content ASTM C 231 (%) spacingfactor(mm) recommended for freeze

  8. Plant cold acclimation and freezing tolerance.

    PubMed

    Hincha, Dirk K; Zuther, Ellen

    2014-01-01

    This introductory chapter provides a brief overview of plant freezing tolerance and cold acclimation and describes the basic concepts and approaches that are currently followed to investigate these phenomena. We highlight the multidisciplinary nature of these investigations and the necessity to use methodologies from different branches of science, such as ecology, genetics, physiology, biochemistry, and biophysics, to come to a complete understanding of the complex adaptive mechanisms underlying plant cold acclimation. PMID:24852623

  9. Insomnia and depression

    Microsoft Academic Search

    Ruth M. Benca; Michael J. Peterson

    2008-01-01

    It is clear that insomnia and depression are intimately related, which may suggest an overlapping neurobiology. Although much progress has been made toward understanding how these disorders relate to each other, the exact neurobiological mechanisms that link them remain elusive. Sleep changes in depression may be associated with abnormal neurotransmission, genetic polymorphisms, HPA overactivity, impaired plasticity, or most likely a

  10. Managing depression in adults

    PubMed Central

    Young, Stephanie

    2009-01-01

    Depression is one of the leading causes of disability worldwide. The majority of patients suffering from depressive disorder are diagnosed and managed in primary care. Optimal management reduces the risk of relapse and improves the quality of life. The main treatment modalities are antidepressants and psychological therapies. Lifestyle changes, exercise and psychoeducation also play an important role in management.

  11. Major Depressive Disorder

    Microsoft Academic Search

    R. H. Belmaker; Galila Agam

    2008-01-01

    epression is related to the normal emotions of sadness and bereavement, but it does not remit when the external cause of these emo- tions dissipates, and it is disproportionate to their cause. Classic severe states of depression often have no external precipitating cause. It is difficult, however, to draw clear distinctions between depressions with and those without psychosocial precipitating events.

  12. Depression in the Workplace

    MedlinePLUS

    ... Lowe SW, Berglund PA, Corey-Lisle PK. The economic burden of depression in the United States: how did it change between 1990 and 2000? Journal of Clinical Psychiatry. December 2003 Dec;64(12):1465-75. ii Employee ... DJ, Burton, WN. Economic Impact of Depression in a Workplace. Journal of ...

  13. Psychotherapy of Depressives

    Microsoft Academic Search

    R. Battegay

    1986-01-01

    People in depressions are submitted to a suffering which always necessitates, in addition to pharmacotherapy, a psychotherapeutic approach. In all the psychotherapies known, a certain attitude of the therapist, which includes an unconditional openness for the patient, is necessary. Depressives cannot bear banal optimism, but need the therapist’s confidence in their future. This human participation helps to fill up, at

  14. [Hashimoto encephalitis and depression].

    PubMed

    Veltman, E M; Rhebergen, D; van Exel, E; Stek, M L

    2015-01-01

    Hashimoto encephalitis (he) is an auto-immune disease, with 40-50% of patients developing psychopathology. This could require targeted treatment. HE and prednison could both cloud the identification of a concurrent depressive disorder. We saw a 78-year-old woman with he and a severe depression, and treated her succesfully with ect. PMID:25904434

  15. Older Adults and Depression

    MedlinePLUS

    ... you well. If you are in a crisis Older adults with depression are at risk for suicide. In fact, white men age 85 and older ... be connected to a trained counselor at a suicide crisis center nearest you. For more information on Older Adults and Depression Contact us to find out more ...

  16. Windchill and the risk of tissue freezing.

    PubMed

    Danielsson, U

    1996-12-01

    Low air temperatures and high wind speeds are associated with an increased risk of freezing of the exposed skin. P. A. Siple and C. F. Passel (Proc. Am. Phil. Soc. 89: 177-199, 1945) derived their windchill index from cooling experiments on a water-filled cylinder to quantify the risk of frostbite. Their results are reexamined here. It is found that their windchill index does not correctly describe the convective heat transfer coefficient (hc) for such a cylinder, the effect of the airspeed (v) is underestimated. New risk curves have been developed, based on the convection equations valid for cylinders in a cross flow, hc infinity v0.62, and tissue freezing data from the literature. An analysis of the data reveals a linear relationship between the frequency of finger frostbite and the surface temperature. This relation closely follows a normal distribution of finger-freezing temperatures, with an SD of 1 degree C. As the skin surface temperature falls from -4.8 to -7.8 degrees C, the risk of frostbite increases from 5 to 95%. These data indicate that the risk of finger frostbite is minor above an air temperature of -10 degrees C, irrespective of v, but below -25 degrees C there is a pronounced risk, even at low v. PMID:9018520

  17. Observations on the Freezing of Supercooled Pollen Washing Water by a New Electrodynamic Balance

    NASA Astrophysics Data System (ADS)

    Tong, Haijie; Pope, Francis D.; Kalberer, Markus

    2014-05-01

    Primary biological particles can act as efficient ice nuclei (IN) by initiating freezing events at temperatures warmer than the homogenous freezing temperature [1, 2]. For example, pollen grain particles can trigger freezing events at temperatures as warm as -5 °C in the contact freezing mode [3]. More recently pollen residues, which are released by washing pollen grains in water, were also observed to act as efficient IN in the immersion mode [4, 5]. In this study we developed a new cold electrodynamic balance (CEDB) system and investigated the freezing properties of single particles of supercooled pollen washing water (SPWW). The EDB technique allows for a contact free measurement of freezing events. The phase of the particle (liquid or frozen solid) can be distinguished via measuring the Mie scattering signal from the particle. Furthermore the size of liquid (spherical) particles can be determined. The freezing events are characterized through the loss of the regular Mie scattering signal from the levitated droplet as it changes state from liquid to a frozen solid. The statistical freezing probabilities of SPWW were obtained in the temperature range: -15 to -40 °C. Each temperature measurement point consists of the analysis of 30-100 droplets. Preliminary conclusions are that SPWW is IN active in the immersion mode. Further discussion will focus on the temperature range of the IN activity, the important variables (other than temperature) for IN activity, other likely modes of IN activity, and the implications of these results in terms of the atmospheric relevance of SPWW. This study was supported by the NERC. We acknowledge Professor Jonathan Reid and James Davis from the University of Bristol for providing information of the design of the warm EDB system. References: [1] Möhler, O., et al. (2007) Biogeosciences, 4, 1059-1071. [2] Prenni, A. J., et al. (2009) Nat. Geosci., 2, 401-404. [3] Diehl, K., et al. (2002) Atmos. Res., 61, 125-133. [4] Pummer, B. G., et al. (2012) Atmos. Chem. Phys., 12, 2541-2550. [5] Augustin, S., et al. (2013) Atmos. Chem. Phys., 13, 10989-11003.

  18. Using the Persian-language version of the Beck Depression Inventory-II (BDI-II-Persian) for the screening of depression in students.

    PubMed

    Vasegh, Sasan; Baradaran, Nafiseh

    2014-10-01

    Early identification and treatment of depression can prevent the development of the full depressive episode and its consequences. Although the Beck Depression Inventory-II is among the most widely used tools for measuring depression, there are relatively few studies that empirically confirm any cutoff points for screening depression among university students. Our subjects were 400 students from Ilam University (Iran). On the basis of a diagnostic interview checklist, the subjects were differentiated whether they were major depressive syndrome positive (MDS+) (i.e., fulfill criteria A and C of major depressive episode Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria) or significant depression positive (SD+) (having depressed mood or anhedonia that caused significant distress or dysfunction). According to receiver operating characteristic curves obtained, the cutoff point of 22 or greater was the most suitable to screen MDS, whereas for screening milder but clinically significant depression (i.e., having depressed mood or anhedonia that caused significant distress or dysfunction), the cutoff point of 14 or greater was the best. PMID:25208346

  19. Fundamental technical elements of freeze-fracture/freeze-etch in biological electron microscopy.

    PubMed

    Carson, Johnny L

    2014-01-01

    Freeze-fracture/freeze-etch describes a process whereby specimens, typically biological or nanomaterial in nature, are frozen, fractured, and replicated to generate a carbon/platinum "cast" intended for examination by transmission electron microscopy. Specimens are subjected to ultrarapid freezing rates, often in the presence of cryoprotective agents to limit ice crystal formation, with subsequent fracturing of the specimen at liquid nitrogen cooled temperatures under high vacuum. The resultant fractured surface is replicated and stabilized by evaporation of carbon and platinum from an angle that confers surface three-dimensional detail to the cast. This technique has proved particularly enlightening for the investigation of cell membranes and their specializations and has contributed considerably to the understanding of cellular form to related cell function. In this report, we survey the instrument requirements and technical protocol for performing freeze-fracture, the associated nomenclature and characteristics of fracture planes, variations on the conventional procedure, and criteria for interpretation of freeze-fracture images. This technique has been widely used for ultrastructural investigation in many areas of cell biology and holds promise as an emerging imaging technique for molecular, nanotechnology, and materials science studies. PMID:25285532

  20. [Depression as chronobiological illness].

    PubMed

    Kálmán, Janos; Kálmán, Sára

    2009-06-01

    Chronobiological problems are always present as aetiological or pathoplastic conditions almost in all psychiatric disorders and considered as the greatest contributors to the mood and sleep disorders associated problems. The present review summarise the recent advances in the chronobiology research from the point of the clinician with particular emphasis on the psychobiology and pharmacotherapy of the depression. Human behaviour builds up from different length of circadian, ultradian and seasonal rhytms, strictly controlled by a hierarchical organisation of sub-cellullar, cellular, neuro-humoral and neuro-immunological clock systems. These internal clock systems are orchestrated at molecular level by certain clock genes and on the other hand--at neuro-humoral level--by the effect of the sleep hormone, melatonine, produced by the neurons of the suprachiasmatic nucleus (SCN). Beside the biological factors, social interactions are also considered as important regulators of the biological clock systems. The pacemaker centers of the SCN receive efferents from the serotoninergic raphe nuclei in order to regulate stress responses and neuroimmunological functions. The direction and the level of the chronobiological desynchronisation could be totally divergent in the case of the different affective disorders. Different chronobiological interventions are required therefore in the case of the advanced and delayed sleep disorders. Sleeping disorders are considered as the most recognised signs of the chronobiological desynchronisation in depression, but these symptoms are only the tip of the iceberg, since other chronobiological symptoms could be present due to the hidden physiological abnormalities. The serum melatonine profile is considered to be characteristic to age, gender and certain neuropsychiatric disorders. The natural and synthetic agonist of the melatonine receptors could be used as chronobiotics. The recently marketed agomelatine with a highly selective receptor binding profile (MT1 and MT2 agonism and 5HT2C antagonism) targets the desynchronised circadian rhytm in affective disorders and it has mainly antidepressive effect. Among the non-pharmacological chronobiological interventions, the different forms of the sleep deprivation, light and social rhytm therapies could offer alternative treatment options for the clinician. PMID:19827314

  1. Psychodynamic treatment of depression.

    PubMed

    Luyten, Patrick; Blatt, Sidney J

    2012-03-01

    Findings reviewed in this article show that PT should be included in treatment guidelines for depression. BPT in particular has been found to be superior to control conditions, equally effective as other active psychological treatments, with treatment effects that are often maintained in the long run, conferring resistance to relapse. Moreover, BPT is as effective as pharmacotherapy in the acute treatment of mild to moderate depression, and, either as monotherapy or combined with medication, BPT is associated with better long-term outcome compared with pharmacotherapy alone. PT is accepted by many depressed patients as a viable and preferred treatment. Furthermore, LTPT and PA have shown promise in treating patients with complex psychological disorders characterized by mood problems, often with comorbid personality problems. Finally, although studies suggest that effects of PT may be achieved somewhat slower compared with other forms of psychotherapy as well as medication in the acute treatment of depression, LTPT appears to be more clinically effective and perhaps more cost effective in the long run, particularly for chronically depressed patients. As noted, these conclusions need to be interpreted within the context of important limitations. Compared with other treatments, the evidence base for PT in depression remains relatively small, despite a respectable research tradition supporting psychodynamic assumptions with regard to the causation of depression. Moreover, and perhaps most importantly, although more studies now include longer follow-up assessments, our knowledge about the long-term effects of so-called evidence-based treatments of depression remains sketchy at best. In this context, the growing evidence for the efficacy and effectiveness of LTPT is promising. Overall, it is clear that the future of the treatment of depression may lie in a combined disorder- and person-centered, tailored-made approach, which takes into account, particularly in chronic depression, the broader interpersonal context and life history of the individual. It is clear that psychodynamic therapies have an important role to play in this respect. PMID:22370494

  2. An electrochemical in situ study of freezing and thawing of ionic liquids in carbon nanopores.

    PubMed

    Weingarth, Daniel; Drumm, Robert; Foelske-Schmitz, Annette; Kötz, Rüdiger; Presser, Volker

    2014-10-21

    Room temperature ionic liquids (RTILs) are an emerging class of electrolytes enabling high cell voltages and, in return, high energy density of advanced supercapacitors. Yet, the low temperature behavior, including freezing and thawing, is little understood when ions are confined in the narrow space of nanopores. This study shows that RTILs may show a tremendously different thermal behavior when comparing bulk with nanoconfined properties as a result of the increased surface energy of carbon pore walls. In particular, a continuous increase in viscosity is accompanied by slowed-down charge-discharge kinetics as seen with in situ electrochemical characterization. Freezing reversibly collapses the energy storage ability and thawing fully restores the initial energy density of the material. For the first time, a different thermal behavior in positively and negatively polarized electrodes is demonstrated. This leads to different freezing and melting points in the two electrodes. Compared to bulk, RTILs in the confinement of electrically charged nanopores show a high affinity for supercooling; that is, the electrode may freeze during heating. PMID:25201074

  3. Theory and numerical application of subsurface flow and transport for transient freezing conditions

    SciTech Connect

    White, M.D. [Pacific Northwest Lab., Richland, WA (United States). Earth and Environmental Sciences Center

    1995-04-01

    Protective barriers are being investigated for the containment of radioactive waste within subsurface environments. Predicting the effectiveness of cryogenic barriers and near-surface barriers in temperate or arctic climates requires capabilities for numerically modeling subsurface flow and transport for freezing soil conditions. A predictive numerical model is developed herein to simulate the flow and transport of radioactive solutes for three-phase (water-ice-air) systems under freezing conditions. This physically based model simulates the simultaneous flow of water, air, heat, and radioactive solutes through variably saturated and variably frozen geologic media. Expressions for ice (frozen water) and liquid water saturations as functions of temperature, interfacial pressure differences, and osmotic potential are developed from nonhysteretic versions of the Brooks and Corey and van Genuchten functions for soil moisture retention. Aqueous relative permeability functions for variably saturated and variably frozen geologic media are developed from the Mualem and Burdine theories for predicting relative permeability of unsaturated soil. Soil deformations, caused by freezing and melting transitions, are neglected. Algorithms developed for predicting ice and liquid water saturations and aqueous-phase permeabilities were incorporated into the finite-difference based numerical simulator STOMP (Subsurface Transport Over Multiple Phases). Application of the theory is demonstrated by the solution of heat and mass transport in a horizontal cylinder of partially saturated porous media with differentially cooled ends, with the colder end held below the liquid water freezing point. This problem represents an essential capability for modeling cryogenic barriers in variably saturated geologic media.

  4. Glutathione protects Lactobacillus sanfranciscensis against freeze-thawing, freeze-drying, and cold treatment.

    PubMed

    Zhang, Juan; Du, Guo-Cheng; Zhang, Yanping; Liao, Xian-Yan; Wang, Miao; Li, Yin; Chen, Jian

    2010-05-01

    Lactobacillus sanfranciscensis DSM20451 cells containing glutathione (GSH) displayed significantly higher resistance against cold stress induced by freeze-drying, freeze-thawing, and 4 degrees C cold treatment than those without GSH. Cells containing GSH were capable of maintaining their membrane structure intact when exposed to freeze-thawing. In addition, cells containing GSH showed a higher proportion of unsaturated fatty acids in cell membranes upon long-term cold treatment. Subsequent studies revealed that the protective role of GSH against cryodamage of the cell membrane is partly due to preventing peroxidation of membrane fatty acids and protecting Na(+),K(+)-ATPase. Intracellular accumulation of GSH enhanced the survival and the biotechnological performance of L. sanfranciscensis, suggesting that the robustness of starters for sourdough fermentation can be improved by selecting GSH-accumulating strains. Moreover, the results of this study may represent a further example of mechanisms for stress responses in lactic acid bacteria. PMID:20208023

  5. Glutathione Protects Lactobacillus sanfranciscensis against Freeze-Thawing, Freeze-Drying, and Cold Treatment?

    PubMed Central

    Zhang, Juan; Du, Guo-Cheng; Zhang, Yanping; Liao, Xian-Yan; Wang, Miao; Li, Yin; Chen, Jian

    2010-01-01

    Lactobacillus sanfranciscensis DSM20451 cells containing glutathione (GSH) displayed significantly higher resistance against cold stress induced by freeze-drying, freeze-thawing, and 4°C cold treatment than those without GSH. Cells containing GSH were capable of maintaining their membrane structure intact when exposed to freeze-thawing. In addition, cells containing GSH showed a higher proportion of unsaturated fatty acids in cell membranes upon long-term cold treatment. Subsequent studies revealed that the protective role of GSH against cryodamage of the cell membrane is partly due to preventing peroxidation of membrane fatty acids and protecting Na+,K+-ATPase. Intracellular accumulation of GSH enhanced the survival and the biotechnological performance of L. sanfranciscensis, suggesting that the robustness of starters for sourdough fermentation can be improved by selecting GSH-accumulating strains. Moreover, the results of this study may represent a further example of mechanisms for stress responses in lactic acid bacteria. PMID:20208023

  6. Effect of sugars on headgroup mobility in freeze-dried dipalmitoylphosphatidylcholine bilayers: solid-state 31P NMR and FTIR studies.

    PubMed Central

    Tsvetkova, N M; Phillips, B L; Crowe, L M; Crowe, J H; Risbud, S H

    1998-01-01

    The effect of the carbohydrates trehalose, glucose, and hydroxyethyl starch (HES) on the motional properties of the phosphate headgroup of freeze-dried dipalmitoylphosphatidylcholine (DPPC) liposomes was studied by means of 31P NMR, Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The results show that trehalose, which is a strong glass former (Tg = 115 degreesC), elevates the onset of the lipid headgroup rotations and preserves some rotational mobility of the phosphate headgroups after cooling from the liquid-crystalline state. Glucose (Tg = 30 degreesC), a very effective depressant of the phase transition temperature of freeze-dried DPPC, markedly elevates the initiation of the temperature of headgroup rotations. On the other hand, the monosaccharide does not preserve the headgroup disordering when cooled from the liquid-crystalline state. These effects are consistent with formation of hydrogen bonds between the OH groups of the sugar and the polar headgroups of DPPC. They show, however, that hydrogen bonding is not sufficient for preservation of the dynamic properties of freeze-dried DPPC. HES, although a very good glass former (Tg > 110 degreesC), does not depress the phase transition temperature and affects only slightly the rotational properties of freeze-dried DPPC. This lack of effect of HES is associated with the absence of direct interactions with the lipid phosphates, as evidenced by the FTIR results. These data show that vitrification of the additive is not sufficient to affect the dynamic properties of dried DPPC. PMID:9826615

  7. Factors that influence freezing in the sub-Antarctic springtail Tullbergia antarctica.

    PubMed

    Worland, M Roger

    2005-08-01

    Effects of 12 biotic and abiotic factors on the freezing point of the sub-Antarctic springtail, Tullbergia antarctica, were investigated. Repeated cooling of individual springtails five times resulted in very similar freezing points suggesting that ice nucleation in this freeze-susceptible species is likely to be initiated by intrinsic factors rather than being a stochastic event. Mean supercooling point (SCP) was influenced by cooling protocol, showing a linear increase in mean SCP with cooling rates from 8 to 0.1 degrees Cmin(-1). However, the opposite effect (decreasing SCP) was seen with slower cooling. Slower rates may be ecologically realistic and allow time for appropriate physiological and biochemical changes. Feeding and food presence in the gut had no effect on SCP, and there was no correlation between the ice nucleating activity of bacteria isolated from the guts and the whole springtail SCP. Habitat altitude and diurnal light and temperature regimes also had no effect on SCP. There was no correlation between the cryoprotectant concentration of fresh animals and their SCP, but experimental desiccation resulted in increased osmolality and decreased SCP, although with considerable individual variation. The most significant influence on SCP was associated with ecdysis. As springtails cease feeding for a period either side of ecdysis, shedding the entire gut lining, moulting may be an efficient mechanism of clearing the gut of all ice nucleating material. This previously unrecognised relationship between ecdysis, cold tolerance and seasonal survival tactics may play an important role in over-winter survival of some arthropods. PMID:15936029

  8. Depression in Older Adults

    PubMed Central

    Fiske, Amy; Wetherell, Julie Loebach; Gatz, Margaret

    2010-01-01

    Depression is less prevalent among older adults than among younger adults but can have serious consequences. Over half of cases represent a first onset in later life. Although suicide rates in the elderly are declining, they are still higher than in younger adults and more closely associated with depression. Depressed older adults are less likely to endorse affective symptoms and more likely to display cognitive changes, somatic symptoms, and loss of interest than are younger adults. Risk factors leading to the development of late life depression likely comprise complex interactions among genetic vulnerabilities, cognitive diathesis, age-associated neurobiological changes, and stressful events. Insomnia is an often overlooked risk factor for late life depression. We suggest that a common pathway to depression in older adults, regardless of which predisposing risks are most prominent, may be curtailment of daily activities. Accompanying self-critical thinking may exacerbate and maintain a depressed state. Offsetting the increasing prevalence of certain risk factors in late life are age-related increases in psychological resilience. Other protective factors include higher education and socioeconomic status, engagement in valued activities, and religious or spiritual involvement. Treatments including behavioral therapy, cognitive behavioral therapy, cognitive bibliotherapy, problem-solving therapy, brief psychodynamic therapy, and life review/reminiscence therapy are effective but too infrequently used with older adults. Preventive interventions including education for individuals with chronic illness, behavioral activation, cognitive restructuring, problem-solving skills training, group support, and life review have also received support. PMID:19327033

  9. [Iatrogenic depression (author's transl)].

    PubMed

    Chevalier, J F; Ginestet, D

    1979-01-01

    A number of drugs are traditionally blamed for causing depression: in general medicine, the antihypertensives, the oral contraceptives and the appetite suppressants; in psychiatry, the neuroleptics. The identification of iatrogenic depression is difficult methodologically, for two reasons: 1. Detection of the depression. 2. Linking convincingly that state of depression with the administration of a particular drug, given the presence of many non-pharmacological factors. The literature and the experience of clinicians provide fairly contradictory evidence, but an analysis of published work calls for the following observations: --the type and severity of depression are rarely specified;--a history of psychiatric disorder is commonly stressed;--the specific role of the disability caused by physical or mental illness and the need to use palliative rather than curative measures are usually underestimated;--biochemically, it is surprising that the effects which some of these drugs are known to have upon the cerebral amines do not cause more depression of mood. In fact, if we consider how widely the drugs incriminated are used, it is clear that real drug-caused depression is rather uncommon. PMID:44864

  10. Castration Depression: Affect, Signal Affect, and/or Depressive Illness?

    PubMed

    Fleischer, Les M

    2015-04-01

    The value of Charles Brenner's ideas regarding depression is assessed, focusing on the significance of castration depressive affect. His discussion of whether depression is an affect, a signal affect, or an illness is examined, with special emphasis on his failure to sufficiently address depression as an illness or disorder as defined by psychiatry. Clinical material from the analysis of a man who suffers from severe depression suggests that incorporating psychiatric concepts (biological and pharmacological) with modern conflict theory can be a useful way to understand and treat some patients with depression. Theoretical and clinical controversies associated with combining psychiatric/biological and psychoanalytic views of depression are examined. PMID:25922375

  11. Post Stroke Depression

    PubMed Central

    Alajbegovic, Azra; Djelilovic-Vranic, Jasminka; Alajbegovic, Salem; Nakicevic, Amina; Todorovic, Ljubica; Tiric-Campara, Merita

    2014-01-01

    ABSTRACT Introduction: Comorbidity of depression and stroke significantly reduces the quality of life of patients after the stroke. Squeal after stroke also determines the quality of life and have impact on the occurrence of depression after the stroke. In our study we investigated the occurrence of depression in patients after different types and subtypes of stroke measured by the Hamilton scale compared to the level of disability measured by NIHSS scale. Goal: The goal was to make a comparative analysis of depression after stroke, according to gender and age, side of the lesion and the severity of neurological deficit. Material and Methods: Material for our work are 210 patients with stroke treated at the Neurology Clinic, Clinical Center of Sarajevo University in 2012, 105 male and 105 female. The mean age of the patients was 67.12±9.5 years. Ischemic stroke was present in 65% cases. There was no statistically significant difference between ischemic and hemorrhagic stroke among genders. In case of hemorrhagic M-56.7%, F-43.3%; ischemic M-48.3%, F-51.7% (chi-square=6.563, p=0.082). Depression was more prevalent among younger patients (52-60 years) with 39.2% then in the group of older patients (61-70 years) with 32% of depressed. In relation to gender there was significantly more patients with depression among women compared to men (63.8:27.2%, chi-square=14.38, p=0.00019). Depression was more frequent in patients with stroke in the left hemisphere medial localization (63%). NIHSS scale average was 16.07 with the minimum of 11 and maximum of 22, F=52.56, p=0.001. Conclusions: We can conclude that depression after stroke is more frequent in younger patients, female patients, patients with localized stroke in the medial left hemisphere and with higher disability score. PMID:24783913

  12. Depression and school performance in middle adolescent boys and girls.

    PubMed

    Fröjd, Sari A; Nissinen, Eeva S; Pelkonen, Mirjami U I; Marttunen, Mauri J; Koivisto, Anna-Maija; Kaltiala-Heino, Riittakerttu

    2008-08-01

    The study aimed to investigate the associations between different levels of depression with different aspects of school performance. The target population included 2516 7th-9th grade pupils (13-17 years) of whom 90% completed the questionnaire anonymously in the classroom. Of the girls 18.4% and of the boys 11.1% were classified as being depressed (R-Beck Depression Inventory (BDI), the Finnish version of the 13-item BDI). The lower the self-reported grade point average (GPA) or the more the GPA had declined from the previous term, the more commonly the adolescents were depressed. Depression was associated with difficulties in concentration, social relationships, self-reliant school performance and reading and writing as well as perceiving schoolwork as highly loading. The school performance variables had similar associations with depression among both sexes when a wide range of depression was studied but gender differences appeared when studying the severe end of the depression scale. Our study indicates that pupils reporting difficulties in academic performance should be screened for depression. PMID:17949806

  13. Insomnia and depression.

    PubMed

    Benca, Ruth M; Peterson, Michael J

    2008-09-01

    It is clear that insomnia and depression are intimately related, which may suggest an overlapping neurobiology. Although much progress has been made toward understanding how these disorders relate to each other, the exact neurobiological mechanisms that link them remain elusive. Sleep changes in depression may be associated with abnormal neurotransmission, genetic polymorphisms, HPA overactivity, impaired plasticity, or most likely a combination of factors. It is therefore crucial that sleep assessments go beyond traditional polysomnography to include a more expanded set of objective measures in the hope that these will uncover the common neurobiology that is thought to underlie insomnia and depression. PMID:18929317

  14. Hippocampal volume in geriatric depression

    Microsoft Academic Search

    David C Steffens; Christopher E Byrum; Douglas R McQuoid; Daniel L Greenberg; Martha E Payne; Timothy F Blitchington; James R MacFall; K. Ranga Rama Krishnan

    2000-01-01

    Background: There is a growing literature on the importance of hippocampal volume in geriatric depression.Methods: We examined hippocampal volume in a group of elderly depressed patients and a group of elderly control subjects (N = 66 geriatric depressed patients and 18 elderly nondepressed control subjects) recruited through Duke’s Mental Health Clinical Research Center for the Study of Depression in the

  15. Design of Freeze-Drying Processes for Pharmaceuticals: Practical Advice

    Microsoft Academic Search

    Michael J. Pikal

    2004-01-01

    Design of freeze-drying processes is often approached with a “trial and error” experimental plan or, worse yet, the protocol used in the first laboratory run is adopted without further attempts at optimization. Consequently, commercial freeze-drying processes are often neither robust nor efficient. It is our thesis that design of an “optimized” freeze-drying process is not particularly difficult for most products,

  16. Trends in Microwave-Assisted Freeze Drying of Foods

    Microsoft Academic Search

    X. Duan; M. Zhang; A. S. Mujumdar; R. Wang

    2010-01-01

    Microwave-assisted freeze drying (MFD) can be accomplished in two distinct ways: freeze drying assisted concurrently with microwave application (MFD-1) and freeze drying and assisted microwave\\/vacuum microwave drying in two consecutive separate drying stages (MFD-2). MFD is a rapid dehydration technique that can be applied to certain foods, particularly to seafoods, solid soup, and fruits and vegetables. MFD involves much less

  17. Arabidopsis ESK1 encodes a novel regulator of freezing tolerance

    Microsoft Academic Search

    Zhanguo Xin; Ajin Mandaokar; Junping Chen; Robert L. Last; John Browse

    2007-01-01

    Summary The eskimo1 (esk1) mutation of Arabidopsis resulted in a 5.5? C improvement in freezing tolerance in the absence of cold acclimation. Here we show that the increase in freezing tolerance is not associated with any increase in the ability to survive drought or salt stresses, which are similar to freezing in their induction of cellular dehydration. Genome-wide comparisons of

  18. Freezing precipitation in the Southeastern United States 

    E-print Network

    Young, William Robert

    1978-01-01

    FREEZING PRECIPITATION IN THE SOUTHEASTERN UNITED STATES A Thesis NILLIAN ROBERT YOUNG Sxhmitted to the Graduate College of Texas ASN University in partial fulfillsent o( the requirement for the decree of RASTER OF SCIENCE NaY 19'7B rV, 'or... Suoject: Net *oroloRY FREE 1NG PRE fPITATION IN THE SOUTHEASTERN UNITED STATES A Thesis 'NXLDIAN ROBERT YOUNG Approved as to style and coni ent hy: Chairman of Committe "Leaser (Head of Departne. "i Niay 19y8 443?10 Freesing Precipitation...

  19. A molecular dynamics study of freezing in a confined geometry

    NASA Technical Reports Server (NTRS)

    Ma, Wen-Jong; Banavar, Jayanth R.; Koplik, Joel

    1992-01-01

    The dynamics of freezing of a Lennard-Jones liquid in narrow channels bounded by molecular walls is studied by computer simulation. The time development of ordering is quantified and a novel freezing mechanism is observed. The liquid forms layers and subsequent in-plane ordering within a layer is accompanied by a sharpening of the layer in the transverse direction. The effects of channel size, the methods of quench, the liquid-wall interaction and the roughness of walls on the freezing mechanism are elucidated. Comparison with recent experiments on freezing in confined geometries is presented.

  20. Anoxia tolerance and freeze tolerance in hatchling turtles.

    PubMed

    Dinkelacker, S A; Costanzo, J P; Lee, R E

    2005-04-01

    Freezing survival in hatchling turtles may be limited by ischemic anoxia in frozen tissues and the associated accumulation of lactate and reactive oxygen species (ROS). To determine whether mechanisms for coping with anoxia are also important in freeze tolerance, we examined the association between capacities for freezing survival and anoxia tolerance in hatchlings of seven species of turtles. Tolerance to freezing (-2.5 degrees C) was high in Emydoidea blandingii, Chrysemys picta, Terrapene ornata, and Malaclemys terrapin and low in Graptemys geographica, Chelydra serpentina, and Trachemys scripta. Hatchlings survived in a N(2) atmosphere at 4 degrees C for periods ranging from 17 d (M. terrapin) to 50 d (G. geographica), but survival time was not associated with freeze tolerance. Lactate accumulated during both stresses, but plasma levels in frozen/thawed turtles were well below those found in anoxia-exposed animals. Activity of the antioxidant enzyme catalase in liver increased markedly with anoxia exposure in most species, but increased with freezing/thawing only in species with low freeze tolerance. Our results suggest that whereas oxygen deprivation occurs during somatic freezing, freeze tolerance is not limited by anoxia tolerance in hatchling turtles. PMID:15739066

  1. Design of a blood-freezing system for leukemia research

    NASA Technical Reports Server (NTRS)

    Williams, T. E.; Cygnarowicz, T. A.

    1978-01-01

    Leukemia research involves the use of cryogenic freezing and storage equipment. In a program being carried out at the National Cancer Institute (NCI), bone marrow (white blood cells) was frozen using a standard cryogenic biological freezer. With this system, it is difficult to maintain the desired rate of freezing and repeatability from sample to sample. A freezing system was developed that satisfies the requirements for a repeatable, constant freezing rate. The system was delivered to NIC and is now operational. This report describes the design of the major subsystems, the analyses, the operating procedure, and final system test results.

  2. Depression in glioma 

    E-print Network

    Rooney, Alasdair Grant

    2011-11-25

    BACKGROUND Few high-quality observational studies have been conducted to examine clinically relevant features of emotional distress and Major Depressive Disorder (MDD) in adults with primary cerebral glioma. Our knowledge ...

  3. Depression and African Americans

    MedlinePLUS

    ... Many people find strength and support through their religious and spiritual communities, however, only a physician or ... diagnose clinical depression. Pastoral counselors offer an integrated religious and spiritual approach to treatment. How do I ...

  4. Depression and Multiple Sclerosis

    MedlinePLUS

    ... various forms is common during the course of multiple sclerosis. In fact, studies have suggested that clinical depression, ... is easy to understand how a diagnosis of multiple sclerosis, a chronic condition with the potential for progressing ...

  5. Effects of Electric and Magnetic Field on Freezing and Possible Relevance in Freeze Drying

    Microsoft Academic Search

    M. W. Woo; A. S. Mujumdar

    2010-01-01

    Application of an electric or magnetic field can significantly affect the freezing characteristics of water. A DC electric field will tend to induce ice nucleation at a lower degree of supercooling, and there is evidence to show that an AC electric field delays the onset of ice nucleation. Industrial research has shown that a magnetic field can be used to

  6. A Psychological Profile of Depressed and Nondepressed Women at High Risk for Breast Cancer

    Microsoft Academic Search

    DAVID K. WELLISCH; NANGEL M. LINDBERG

    2001-01-01

    This study examines the difference on several demographic and psychosocial variables between women at high risk for breast cancer above and below the cut-off point of a depression measure (Center for Epidemiological Study Depression Scale). Data are presented for 430 consecutive pa- tients from the UCLA Revlon Breast Center High Risk Clinic. Women scoring above the depres- sion cut-off point

  7. Effect of freeze drying and protectants on viability of the biocontrol yeast Candida sake

    Microsoft Academic Search

    M Abadias; A Benabarre; N Teixidó; J Usall; I Viñas

    2001-01-01

    The effects of freezing method, freeze drying process, and the use of protective agents on the viability of the biocontrol yeast Candida sake were studied. Freezing at ?20°C was the best method to preserve the viability of C. sake cells after freeze drying using 10% skim milk as a protectant (28.9% survival). Liquid nitrogen freezing caused the highest level of

  8. [Depression and aging].

    PubMed

    Lôo, Henri; Gallarda, Thierry; Fabre, Isabelle; Olié, Jean-Pierre

    2004-01-01

    Depression is one of the most common health disorders in elderly people. It is still often considered as a natural consequence of aging, arising in reaction to a medical disease, cognitive or functional decline, or a loss of social fabric. Many studies have highlighted the low rates of diagnosis and treatment of depression, especially in the primary care setting. Major depression in old age is characterized by the same core symptoms as in other periods of life. However, aging may accentuate some symptoms and alleviate others. Somatic concern, marked anxiety, poor subjective memory, psychotic ideation, and recurrent thoughts of death can mask sadness and anhedonia. Organic factors and adverse life events are often intricately linked with the pathogenesis of depressive states in the elderly. The role of cerebrovascular lesions has also been established, particularly in late-onset depressive disorders. The management of depressive disorders in older people, as in younger adults, involves pharmacological and psychological treatments. Electroconvulsive therapy can be beneficial in some cases. Transcranial magnetic stimulation is being evaluated in this setting. PMID:15651428

  9. Effect of repeated freeze-thaw cycles on geographically different populations of the freeze-tolerant worm Enchytraeus albidus (Oligochaeta).

    PubMed

    Fisker, Karina Vincents; Holmstrup, Martin; Malte, Hans; Overgaard, Johannes

    2014-11-01

    Freeze-tolerant organisms survive internal ice formation; however, the adaptations to repeated freeze-thaw cycles are often not well investigated. Here we report how three geographically different populations of Enchytraeus albidus (Germany, Iceland and Svalbard) respond to three temperature treatments - constant thawed (0°C), constant freezing (-5°C) and fluctuating temperature (0 to -5°C) - over a period of 42 days. Survival varied between treatments and populations such that enchytraeids from arctic locations had a higher survival following prolonged freeze periods compared with temperate populations. However, enchytraeids from temperate locations had the same survival rate as arctic populations when exposed to repeated freeze-thaw events. Across all populations, metabolic rate decreased markedly in frozen animals (-5°C) compared with thawed controls (0°C). This decrease is likely due to the lower temperature of frozen animals, but also to the transition to the frozen state per se. Animals exposed to repeated freeze-thaw events had an intermediate metabolic rate and freeze-thaw events were not associated with pronounced excess energetic costs. Overwintering under either condition was not associated with a decrease in lipid content; however, during exposure to constant freezing and repeated freeze-thaw events there was a noticeable decrease in carbohydrate stores over time. Thus, animals exposed to constant freezing showed a decrease in glycogen stores, while both glucose and glycogen content decreased over time when the organisms were exposed to repeated freezing. The results therefore suggest that carbohydrate resources are important as a fuel for E. albidus during freezing whereas lipid resources are of marginal importance. PMID:25214492

  10. RESPONSES TO FREEZING EXPOSURE OF HATCHLING TURTLES TRACHEMYS SCRIPTA ELEGANS: FACTORS INFLUENCING THE DEVELOPMENT OF FREEZE TOLERANCE BY REPTILES

    Microsoft Academic Search

    THOMAS A. CHURCHILL; KENNETH B. STOREY

    Summary Hatchling red-eared turtles Trachemys (=Pseudemys) scripta elegans (Wied) from a Louisiana population display a significant ability to withstand the freezing of extracellular body fluids. All animals survived at least 2 h of freezing at -2.5 or —4°C. At -2.5°C, survival declined to 50% after 6h of freezing and no animals recovered after 24 h or longer, when mean ice

  11. Sexual minority status, peer harassment, and adolescent depression.

    PubMed

    Martin-Storey, Alexa; Crosnoe, Robert

    2012-08-01

    The well-documented higher rates of depression among sexual minority youth are increasingly viewed by developmentalists as a byproduct of the stigmatization of sexual minority status in American society and of the negative impact this stigma has on the processes associated with depression. This study attempted to spur future research by testing Hatzenbuehler's (2009) psychological mediation framework to investigate the ways in which peer harassment related to sexuality puts young people at risk by influencing the cognitive, social, and regulatory factors associated with depression. Analyses of 15 year olds in the NICHD Study of Early Child Care and Youth Development revealed that sexual minority status was largely associated with depressive outcomes via harassment, which was subsequently associated with depression via cognitive and social factors. Results point to various avenues for exploring the importance of the social world and self-concept for the outcomes of sexual minority adolescents in the future. PMID:22401842

  12. Freezing stress response in woody tissues observed using low-temperature scanning electron microscopy and freeze substitution techniques.

    PubMed

    Malone, S R; Ashworth, E N

    1991-03-01

    The objective of the current research was to examine the response of woody plant tissues to freezing stress by using scanning electron microscopy (SEM). Nonsupercooling species red osier dogwood (Cornus stolonifera Michx.), weeping willow (Salix babylonica L.), and corkscrew willow (Salix matsudana Koidz. f. tortuosa Rehd.) survived freezing stress as low as -60 degrees C. Cell collapse of ray parenchyma cells of these species was expected but did not occur. It was concluded that ray parenchyma cells of these species do not fit into either the supercooling or extracellular freezing classifications. Tissues from flowering dogwood (Cornus florida L.), apple (Malus domestica Borkh. cv "Starking III"), red oak (Quercus rubra L.), scarlet oak (Quercus coccinea Muench.), and red ash (Fraxinus pennsylvanica Marsh) were confirmed as supercooling species, and did not survive exposures below -40 degrees C. Ray parenchyma cells of these species did not collapse in response to freezing stress, as was expected. Cell collapse along the margins of voids were observed in bark of all seven species. Voids were the result of extracellular ice crystals formed in the bark during exposure to freezing stress. Tissues prepared by freeze substitution techniques were found to be adequately preserved when compared to those prepared by conventional fixation and low temperature SEM techniques. A freezing protocol for imposing freezing stress at temperatures lower than experienced naturally in the area where the study was conducted was developed that produced responses comparable to those observed in specimens collected in the field during natural freezing events. PMID:16668066

  13. [Rapid freezing of biologic tissue. Measurement of temperature and rate of freezing by thin-layer thermocouple].

    PubMed

    Escaig, J; Géraud, G; Nicolas, G

    1977-06-13

    An apparatus for rapid freezing of biological tissues by contact with a copper block cooled by liquid helium has been devised to reduce the contamination of copper block surface. It prevents the precooling of the specimen while going through the layers of cold helium gas surrounding the copper block and reduces the quantity of helium necessary for freezing. It also enables one to obtain easily reproducible results from freezing by immersion in liquid coolants. Freezing rates are measured directly, related to the specimen thickness, by a thin film thermocouple; its low thermal inertia gives speed measurements of the order of 100,000 degrees C/s. PMID:408040

  14. Interplay between demixing and freezing in two-dimensional symmetrical mixtures.

    PubMed

    Patrykiejew, A; Soko?owski, S

    2010-01-01

    The interplay between demixing and freezing in two-dimensional symmetrical binary mixtures of Lennard-Jones particles is studied using Monte Carlo simulation. It is demonstrated that different scenarios are possible. For example, the line of continuous liquid demixing transition can start at the liquid side of the vapor-liquid coexistence at the lower critical end point and then it can terminate at the liquid side of the liquid-demixed solid coexistence at the upper critical end point. Other situations are also possible. We distinguish four different scenarios depending on the interactions between unlike particles. PMID:20365417

  15. Quality and severity of depression in borderline personality disorder: A systematic review and meta-analysis.

    PubMed

    Köhling, Johanna; Ehrenthal, Johannes C; Levy, Kenneth N; Schauenburg, Henning; Dinger, Ulrike

    2015-04-01

    Depression in borderline personality disorder (BPD) is hypothesized to be distinct in quality and severity. This paper provides a systematic review of depression quality, and a meta-analysis of depression severity in BPD patients compared to those with depressive disorders (DeDs) only. Based on a systematic literature search, 26 studies were identified for systematic review and 35 studies (3425 participants) were included for meta-analysis. The review focused on different forms of depressive symptoms, affective impairment, self-evaluation, and negative interpersonal experiences. The meta-analysis examined age, gender, presence of comorbid DeDs in BPD patients, and type of depression scale as moderators of effect sizes. Findings indicate that depression quality in BPD is characterized by higher anger/hostility and self-criticism. There was no significant difference in depression severity between BPD and DeD groups, and a high level of heterogeneity. Moderator analyses revealed lower depression severity in BPD patients without comorbid DeDs, but higher severity in BPD patients with comorbid DeDs compared to depressed controls. Our results suggest high variability in depression severity across BPD patients, point toward the consideration of comorbid DeDs, and lend partial support to a BPD-specific depression quality. We discuss difficulties in research on depression in BPD, and offer directions for future studies. PMID:25723972

  16. [Effect of freezing and cooking on the texture and electrophoretic pattern of the proteins of octopus arms (Octopus vulgaris)].

    PubMed

    Reyes, Genara; Nirchio, Mauro; Bello, Rafael; Borderías, Javier

    2014-09-01

    Texture is the most valuable feature in cephalopods. Factors that mainly affect the texture of octopus are: freezing, scalding and cooking. The aim of this study was to assess the effect of freezing, scalding and length of cooking time on the texture and electrophoretic pattern of proteins of octopus arms. Octopuses were trapped near Margarita Island and carried with ice to the laboratory where they were packed and subjected to: a) freezing at -27 degrees C or at -20 degrees C b) scalding c) cooking for 25 min, 35 min or 45 min. Shear force was determined by Kramer cell on strips of octopus arms. SDS-PAGE was done according to the Laemmli method with 12% polyacrilamide gels. A sensory evaluation of the preference of texture was carried out using a hedonic scale of 7-points and a non-trained panel. Octopus texture was not affected by freezing temperature or scalding. Frozen octopus was softer after cooking than fresh. The longer the cooking time was, the softer the octopus was. Myosin heavy chain (MHC) was not significantly affected by scalding or cooking; however large aggregates heavier than MHC, new bands and loss of resolution of the bands appeared. Myosin and paramyosin bands were more affected by freezing prior to cooking. PMID:26137796

  17. Children and depression--the children of depressed parents; the childhood of depressed patients; depression in children.

    PubMed

    Orvaschel, H; Weissman, M M; Kidd, K K

    1980-03-01

    In order to understand the development of depression in children, three types of data are reviewed: (1) studies of the children of depressed parents; (2) studies of the childhood histories of depressed adults; (3) direct studies of depression in children. These data support an increased frequency of depression and other psychopathology in the children of depressed adults. An examination of the homes of children with a depressed parent reveals a disruptive, hostile, and rejecting environment. This atmosphere is also found in the homes of depressed children and in the homes of children who become depressed as adults. Methodological issues are discussed which will help sort out the relative influences of genes and environment in future studies. PMID:6448876

  18. Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors

    SciTech Connect

    Gomez, A.; Villanueva, R.; Vie, D.; Murcia-Mascaros, S.; Martinez, E.; Beltran, A. [Institut de Ciencia dels Materials, Parc Cientific, Universitat de Valencia, PO Box 22085, 46071 Valencia (Spain); Sapina, F., E-mail: fernando.sapina@uv.es [Institut de Ciencia dels Materials, Parc Cientific, Universitat de Valencia, PO Box 22085, 46071 Valencia (Spain); Vicent, M.; Sanchez, E. [Instituto de Tecnologia Ceramica-Asociacion de Investigacion de las Industrias Ceramicas, Universitat Jaume I, 12006 Castellon (Spain)

    2013-01-15

    Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10-15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and the nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures. - Graphical abstract: Zr{sub 1-x}A{sub x}O{sub 2-x/2} (A=Y, Sc; 0{<=}x{<=}0.12) solid solutions have been prepared as nanostructured powders by thermal decomposition of precursors obtained by freeze-drying, and this synthetic procedure has been scaled up to the 100 g scale. Highlights: Black-Right-Pointing-Pointer Zr{sub 1-x}A{sub x}O{sub 2-x/2} (A=Y, Sc; 0{<=}x{<=}0.12) solid solutions have been prepared as nanostructured powders. Black-Right-Pointing-Pointer The synthetic method involves the thermal decomposition of precursors obtained by freeze-drying. Black-Right-Pointing-Pointer The temperature of the thermal treatment controls particle sizes. Black-Right-Pointing-Pointer The preparation procedure has been scaled up to the 100 g scale. Black-Right-Pointing-Pointer This method is appropriate for the large-scale industrial preparation of multimetallic systems.

  19. SFT: a consistent checkpointing algorithm with shorter freezing time

    Microsoft Academic Search

    Xiaohui Wei; Jiubin Ju

    1998-01-01

    SFT algorithm, a consistent checkpointing algorithm with shorter freezing time, is presented in this paper. SFT is able to implement fault-tolerance in distributed systems. The features of the algorithm include shorter freezing time, lower overhead, and simple roll backing. To reduce checkpointing time, a special control message (Munblock) is used to ensure that at any given time a process can

  20. St. Lawrence River Freeze-Up Forecast Procedure.

    ERIC Educational Resources Information Center

    Assel, R. A.

    A standard operating procedure (SOP) is presented for calculating the date of freeze-up on the St. Lawrence River at Massena, N.Y. The SOP is based on two empirical temperature decline equations developed for Kingston, Ontario, and Massena, N.Y., respectively. Input data needed to forecast freeze-up consist of the forecast December flow rate and…

  1. Studies on Freezing RAM Semen in Absence of Glycerol

    Microsoft Academic Search

    Abdelhady Abdelhakeam Abdelnaby

    1988-01-01

    Glycerol is widely used as a major cryoprotective agent for freezing spermatozoa of almost all species. However, it reduces fertility of sheep inseminated cervically compared with intrauterine insemination. Studies were conducted to develop a method and procedure for freezing ram semen in the absence of glycerol. Post -thaw survival of ram spermatozoa frozen in the absence of glycerol was affected

  2. Promising freeze protection alternatives in solar domestic hot water systems

    Microsoft Academic Search

    1997-01-01

    Since the gains associated with solar thermal energy technologies are comparatively small in relation to the required capital investment, it is vital to maximize conversion efficiency. While providing the necessary function of freeze protection, the heat exchanger commonly included in solar domestic water heating systems represents a system inefficiency. This thesis explores two alternate methods of providing freeze protection without

  3. Freeze Out Process with In-Medium Nucleon Mass

    E-print Network

    Sven Zschocke; Laszlo P. Csernai; Etele Molnár; Jaakko Manninen; Agnes Nyiri

    2006-10-16

    We investigate the kinetic freeze out scenario of a nucleon gas through a finite layer. The in-medium mass modification of nucleons and it's impact on the freeze out process is studied. A considerable modification of the thermodynamical parameters temperature, flow-velocity, energy density and particle density has been found in comparison with evaluations which use a constant vacuum nucleon mass.

  4. Using infrared thermography to study freezing in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Factors that determine when and to what extent a plant will freeze are complex. While thermocouples have served as the main method of monitoring the freezing process in plants, infrared thermography offers distinct advantages, and the use of this latter technology has provided new insights on the p...

  5. Determination of freeze-out conditions from lattice QCD calculations

    NASA Astrophysics Data System (ADS)

    Karsch, Frithjof

    2012-12-01

    Freeze-out conditions in Heavy Ion Collisions are generally determined by comparing experimental results for ratios of particle yields with theoretical predictions based on applications of the Hadron Resonance Gas model. We discuss here how this model dependent determination of freeze-out parameters may eventually be replaced by theoretical predictions based on equilibrium QCD thermodynamics.

  6. Logistic Regression Analysis of Freezing Tolerance in Winter Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four winter wheat cultivars, Eltan, Froid, Kestrel, and Tiber, were cold-acclimated for five weeks and then tested for freezing tolerance in a programmable freezer. The temperature of the soil was recorded every two minutes and the freezing episode was described as five parameters: the minimum temp...

  7. 14 CFR 25.1455 - Draining of fluids subject to freezing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Draining of fluids subject to freezing. 25.1455 Section 25...Miscellaneous Equipment § 25.1455 Draining of fluids subject to freezing. If fluids subject to freezing may be drained...

  8. 14 CFR 25.1455 - Draining of fluids subject to freezing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Draining of fluids subject to freezing. 25.1455 Section 25...Miscellaneous Equipment § 25.1455 Draining of fluids subject to freezing. If fluids subject to freezing may be drained...

  9. 14 CFR 25.1455 - Draining of fluids subject to freezing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Draining of fluids subject to freezing. 25.1455 Section 25...Miscellaneous Equipment § 25.1455 Draining of fluids subject to freezing. If fluids subject to freezing may be drained...

  10. 14 CFR 25.1455 - Draining of fluids subject to freezing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Draining of fluids subject to freezing. 25.1455 Section 25...Miscellaneous Equipment § 25.1455 Draining of fluids subject to freezing. If fluids subject to freezing may be drained...

  11. 14 CFR 25.1455 - Draining of fluids subject to freezing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Draining of fluids subject to freezing. 25.1455 Section 25...Miscellaneous Equipment § 25.1455 Draining of fluids subject to freezing. If fluids subject to freezing may be drained...

  12. Short versions of the geriatric depression scale: a study of their validity for the diagnosis of a major depressive episode according to ICD10 and DSM-IV

    Microsoft Academic Search

    Osvaldo P. Almeida; Shirley A. Almeida

    1999-01-01

    Objective. To determine the validity of short Geriatric Depression Scale (GDS) versions for the detection of a major depressive episode according to ICD-10 criteria for research and DSM-IV. Design. Cross-sectional evaluation of depressive symptoms in a sample of elderly subjects with short GDS versions. DiÄerent GDS cutoÄ points were used to estimate the sensitivity, specificity, positive predictive value and negative

  13. Screening for depression.

    PubMed

    Maurer, Douglas M

    2012-01-15

    In the United States, depression affects up to 9 percent of patients and accounts for more than $43 billion in medical care costs. The U.S. Preventive Services Task Force recommends screening in adolescents and adults in clinical practices that have systems in place to ensure accurate diagnosis, effective treatment, and follow-up. It does not recommend for or against screening for depression in children seven to 11 years of age or screening for suicide risk in the general population. The Patient Health Questionnaire (PHQ)-2 and PHQ-9 are commonly used and validated screening tools. The PHQ-2 has a 97 percent sensitivity and 67 percent specificity in adults, whereas the PHQ-9 has a 61 percent sensitivity and 94 percent specificity in adults. If the PHQ-2 is positive for depression, the PHQ-9 should be administered; in older adults, the 15-item Geriatric Depression Scale is also an appropriate follow-up test. If these screening tests are positive for depression, further evaluation is needed to confirm that the patient's symptoms meet the Diagnostic and Statistical Manual of Mental Disorders' criteria for diagnosis. PMID:22335214

  14. Photomicrographic Investigation of Spontaneous Freezing Temperatures of Supercooled Water Droplets

    NASA Technical Reports Server (NTRS)

    Dorsch, R. G.; Hacker, P. T.

    1950-01-01

    A photomicrographic technique for investigating eupercooled. water droplets has been devised and. used. to determine the spontaneous freezing temperatures of eupercooled. water droplets of the size ordinarily found. in the atmosphere. The freezing temperatures of 4527 droplets ranging from 8.75 to 1000 microns in diameter supported on a platinum surface and 571 droplets supported on copper were obtained. The average spontaneous freezing temperature decreased with decrease in the size of the droplets. The effect of size on the spontaneous freezing temperature was particularly marked below 60 microns. Frequency-distribution curves of the spontaneous freezing temperatures observed for droplets of a given size were obtained. Although no droplet froze at a temperature above 20 0 F, all droplets melted at 32 F. Results obtained with a copper support did not differ essentially from those obtained with a platinum surface.

  15. Freeze plug proves safe, economical in riser repair

    SciTech Connect

    Nelson, M.J. [Exxon Co. U.S.A., New Orleans, LA (United States)

    1995-05-01

    In October 1992, Exxon Pipeline Co., Houston, performed in the Gulf of Mexico what the company believes to have been the first underwater freeze-plug procedure. To form a plug, water in a small section of the pipe is frozen with liquid nitrogen. In partially replacing a 10-in. riser at South Marsh Island Block 6A, Exxon Pipeline worked closely with a freeze-plug service company to minimize environmental and personnel exposure and to avoid the chance of an oil spill. The freeze plug reduced the time the pipe was open-ended during the repair, and hydrotesting the freeze plug area and repair section ensured integrity. The paper describes onshore testing of the procedures, pre-work surface cleaning, and the freeze-plug procedure.

  16. Evaluation and Validation of the Messinger Freezing Fraction

    NASA Technical Reports Server (NTRS)

    Anderson, David N.; Tsao, Jen-Ching

    2005-01-01

    One of the most important non-dimensional parameters used in ice-accretion modeling and scaling studies is the freezing fraction defined by the heat-balance analysis of Messinger. For fifty years this parameter has been used to indicate how rapidly freezing takes place when super-cooled water strikes a solid body. The value ranges from 0 (no freezing) to 1 (water freezes immediately on impact), and the magnitude has been shown to play a major role in determining the physical appearance of the accreted ice. Because of its importance to ice shape, this parameter and the physics underlying the expressions used to calculate it have been questioned from time to time. Until now, there has been no strong evidence either validating or casting doubt on the current expressions. This paper presents experimental measurements of the leading-edge thickness of a number of ice shapes for a variety of test conditions with nominal freezing fractions from 0.3 to 1.0. From these thickness measurements, experimental freezing fractions were calculated and compared with values found from the Messinger analysis as applied by Ruff. Within the experimental uncertainty of measuring the leading-edge thickness, agreement of the experimental and analytical freezing fraction was very good. It is also shown that values of analytical freezing fraction were entirely consistent with observed ice shapes at and near rime conditions: At an analytical freezing fraction of unity, experimental ice shapes displayed the classic rime shape, while for conditions producing analytical freezing fractions slightly lower than unity, glaze features started to appear.

  17. Ni20Cr and 304L stainless steel powders coated with a melting point depressant, Ni 7 UP, were used as the interlayers to produce large root opening 304 stainless steel joints

    Microsoft Academic Search

    W. D. ZHUANG; T. W. EAGAR

    Powder particles coated with a small amount of melting point de- pressant (MPD) reveal different sintering behavior in comparison to an uncoated powder mixture of the same composi- tion. Interlayers consisting of the coated powder particles were used in the tran- sient liquid-phase (TLP) bonding process. The coating material and the thickness of the deposit are important parameters that influence

  18. Clarification on Mechanical Characteristic in State of Stress of Osteoarthritis of the Hip Joint Using Stress Freezing Method

    NASA Astrophysics Data System (ADS)

    Maezaki, Nobutaka; Ezumi, Tsutomu; Hachiya, Masashi

    In this research, the Osteoarthritis of Hip Joint was pick up, the 3-dimensional stress freezing method of photoelastic method was applied, and the state of the stress in the normality hip joint and the transformable hip joint was examined. The direction and the singular point of principal stress and stress distribution were experimentally examined. At result, The Osteoarthritis of Hip Joint touches by 2 points, Osteoarthritis of Hip Joint occurrence of the new singular point with flat of the femoral head, They change the direction of the principal stress line in an existing singular point is cause.

  19. Immersion freezing of birch pollen washing water

    NASA Astrophysics Data System (ADS)

    Augustin, S.; Wex, H.; Niedermeier, D.; Pummer, B.; Grothe, H.; Hartmann, S.; Tomsche, L.; Clauss, T.; Voigtländer, J.; Ignatius, K.; Stratmann, F.

    2013-11-01

    Birch pollen grains are known to be ice nucleating active biological particles. The ice nucleating activity has previously been tracked down to biological macromolecules that can be easily extracted from the pollen grains in water. In the present study, we investigated the immersion freezing behavior of these ice nucleating active (INA) macromolecules. Therefore we measured the frozen fractions of particles generated from birch pollen washing water as a function of temperature at the Leipzig Aerosol Cloud Interaction Simulator (LACIS). Two different birch pollen samples were considered, with one originating from Sweden and one from the Czech Republic. For the Czech and Swedish birch pollen samples, freezing was observed to start at -19 and -17 °C, respectively. The fraction of frozen droplets increased for both samples down to -24 °C. Further cooling did not increase the frozen fractions any more. Instead, a plateau formed at frozen fractions below 1. This fact could be used to determine the amount of INA macromolecules in the droplets examined here, which in turn allowed for the determination of nucleation rates for single INA macromolecules. The main differences between the Swedish birch pollen and the Czech birch pollen were obvious in the temperature range between -17 and -24 °C. In this range, a second plateau region could be seen for Swedish birch pollen. As we assume INA macromolecules to be the reason for the ice nucleation, we concluded that birch pollen is able to produce at least two different types of INA macromolecules. We were able to derive parameterizations for the heterogeneous nucleation rates for both INA macromolecule types, using two different methods: a simple exponential fit and the Soccer ball model. With these parameterization methods we were able to describe the ice nucleation behavior of single INA macromolecules from both the Czech and the Swedish birch pollen.

  20. Depression after myocardial infarction.

    PubMed Central

    Kavanagh, T.; Shephard, R. J.; Tuck, J. A.

    1975-01-01

    The Minnesota Multiphasic Personality Inventory was completed by 101 patients 16 to 18 months after a proved myocardial infarction. The data suggested a bimodal distribution of patients. One class of patients had a relatively "normal" personality score apart from a tendency to hypomania. The second class had severe depression, with associated hysteria, hypochondriasis and psychasthenia. The severely depressed patients were older, with a greater tendency to hypertension and angina, and a tendency to smaller gains in aerobic power despite an equal intensity of endurance training. The distinction between "normal" and "depressed" postinfarction patients seems of some clinical importance, for the two classes of patients require opposite supportive techniques--restraint and encouragement, respectively. PMID:1148970

  1. It's My Life: Depression

    NSDL National Science Digital Library

    2002-01-01

    It's My Life, a PBS Kids Web-based educational series, offers 9-12 year olds a kid-friendly way to explore and share the issues in their lives. Depression is just one of many subjects addressed in It's My Life. Topics covered in this Web site include defining depression, recognizing the symptoms, understanding the causes, getting treatment, how to help a friend or parent who may be suffering from depression, and more. In addition to articles on these topics, the Web site provides interactive activities -- such as a quiz and a chat room -- that help kids further their understanding of the disease and reach out for help if needed. Offline activities include a printable journal page, a recommended reading list, and discussion questions that kids can take to a parent or friend.

  2. Fabrication of porous ceramics by freeze-casting/freeze-drying. Final report, April 1991-December 1992

    SciTech Connect

    Johnson, S.M.; Gusman, M.I.

    1993-04-01

    Porous ceramics have many applications in the gas industry, including gas separation, filtration, catalyst supports and substrates, lightweight insulation, and burners. The report explores the fabrication of porous ceramics by a new approach involving the use of cryogenic processing techniques such as freeze-drying, to characterize the materials formed in this way, and to evaluate the potential of the techniques for making porous ceramics for specific gas industry applications.

  3. Effects of freezing rates and cryoprotectant on thermal expansion of articular cartilage during freezing process.

    PubMed

    Xu, Y; Sun, H J; Lv, Y; Zou, J C; Lin, B L; Hua, T C

    2013-01-01

    The intact articular cartilage has not yet been successfully preserved at low temperature most likely due to the volume expansion from water to ice during freezing. The objective of this current study focuses on examining thermal expansion behavior of articular cartilage (AC) during freezing from 0 degree C to -100 degree C. Thermo Mechanical Analysis (TMA) was used to investigate the effects of different concentrations of dimethyl sulphoxide (DMSO) (0%, 10%, 30% and 60% v/v) and different freezing rates (1 C/min, 3 C/min and 5 C/min). The results showed that: (1) the inhomogeneous thermal expansion (or contraction) presents due to inhomogeneous water distributions in articular cartilage during freezing, which also may be the most likely reason that the matrix has been damaged in cryopreserved intact articular cartilage; (2) at the phase transition temperature range, the maximum thermal strain change value for 5C/min is approximately 1.45 times than that for 1 C/min, but the maximum thermal expansion coefficient of the later is about six times than that of the former; (3) the thermal expansion coefficient decreases with increasing cooling rate at the unfrozen temperature region, but some opposite results are obtained at the frozen temperature region; (4) the higher the DMSO concentration is, at the phase change temperature region, the smaller the thermal strain change as well as the maximum thermal expansion coefficient are, but DMSO concentration exhibits little effect on the thermal expansion coefficient at both unfrozen and frozen region. Once the DMSO concentration increasing enough, e.g. 60% v/v, the thermal strain decreases linearly and smoothly without any abrupt change due to little or no ice crystal forms (i.e. vitrification) in frozen articular cartilage. This study may improve our understanding of the thermal expansion (or contraction) behavior of cryopreserved articular cartilage and it may be useful for the future study on cryopreservation of intact articular cartilage. PMID:23995399

  4. Hopelessness, Depression, Suicidal Ideation, and Clinical Diagnosis of Depression.

    ERIC Educational Resources Information Center

    Beck, Aaron T.; And Others

    1993-01-01

    Examined relevance of clinical diagnosis of depression for explaining discrepant relationships of hopelessness and depression with suicidal ideation. Administered Beck Depression Inventory, Hopelessness Scale, and Scale for Suicide Ideation to 1,306 patients with mood disorder and 488 patients without mood disorder. Found that hopelessness was 1.3…

  5. The Vascular Depression Hypothesis: Mechanisms Linking Vascular Disease with Depression

    PubMed Central

    Taylor, Warren D.; Aizenstein, Howard J.; Alexopoulos, George S.

    2013-01-01

    The ‘Vascular Depression’ hypothesis posits that cerebrovascular disease may predispose, precipitate, or perpetuate some geriatric depressive syndromes. This hypothesis stimulated much research that has improved our understanding of the complex relationships between late-life depression (LLD), vascular risk factors, and cognition. Succinctly, there are well-established relationships between late-life depression, vascular risk factors, and cerebral hyperintensities, the radiological hallmark of vascular depression. Cognitive dysfunction is common in late-life depression, particularly executive dysfunction, a finding predictive of poor antidepressant response. Over time, progression of hyperintensities and cognitive deficits predicts a poor course of depression and may reflect underlying worsening of vascular disease. This work laid the foundation for examining the mechanisms by which vascular disease influences brain circuits and influences the development and course of depression. We review data testing the vascular depression hypothesis with a focus on identifying potential underlying vascular mechanisms. We propose a disconnection hypothesis, wherein focal vascular damage and white matter lesion location is a crucial factor influencing neural connectivity that contributes to clinical symptomatology. We also propose inflammatory and hypoperfusion hypotheses, concepts that link underlying vascular processes with adverse effects on brain function that influence the development of depression. Testing such hypotheses will not only inform the relationship between vascular disease and depression but also provide guidance on the potential repurposing of pharmacological agents that may improve late-life depression outcomes. PMID:23439482

  6. Effect of wettability on sessile drop freezing: when superhydrophobicity stimulates an extreme freezing delay.

    PubMed

    Boinovich, Ludmila; Emelyanenko, Alexandre M; Korolev, Vadim V; Pashinin, Andrei S

    2014-02-18

    An increasing number of studies directed at supercooling water droplets on surfaces with different wettabilities have appeared in recent years. This activity has been stimulated by the recognition that water supercooling phenomena can be effectively used to develop methods for protecting outdoor equipment and infrastructure elements against icing and snow accretion. In this article, we discuss the nucleation kinetics of supercooled sessile water droplets on hydrophilic, hydrophobic, and superhydrophobic surfaces under isothermal conditions at temperatures of -8, -10, and -15 °C and a saturated water vapor atmosphere. The statistics of nucleation events for the ensembles of freezing sessile droplets is completed by the detailed analysis of the contact angle temperature dependence and freezing of individual droplets in a saturated vapor atmosphere. We have demonstrated that the most essential freezing delay is characteristic of the superhydrophobic coating on aluminum, with the texture resistant to contact with ice and water. This delay can reach many hours at T = -8 °C and a few minutes at -23 °C. The observed behavior is analyzed on the basis of different nucleation mechanisms. The dissimilarity in the total nucleation rate, detected for two superhydrophobic substrates having the same apparent contact angle of the water drop but different resistivities of surface texture to the contact with water/ice, is associated with the contribution of heterogeneous nucleation on external centers located at the water droplet/air interface. PMID:24491217

  7. [Biochemistry of depression].

    PubMed

    Paasche, I

    1976-02-01

    1. In patients with endogenous depression a functional deficiency of noradrenalin and serotonin is presupposed. This hypothesis is based on examinations of the metabolites of these transmitter substances in the cerebrospinal fluid and in the urine. 2. Attempts to compensate the deficiency by means of precursors of the transmitter show a great variety of therapeutic effects. Possible metabolic regulations are discussed. 3. Changes of hormone metabolism are involved in the disease, these are discussed. 4. At present valid statements on the causes of a biochemical defect in depressive illness are not possible. PMID:181773

  8. Depression symptomatology and neurobiology.

    PubMed

    Gelenberg, Alan J

    2010-01-01

    The DSM-IV-TR distinguishes major depressive disorder (MDD) from normal sadness and grief by requiring a certain duration and number of symptoms that cause impairment and dysfunction. Depression is considered a heterogeneous condition in which different biologic abnormalities may be responsible for problems with sleeping, eating, energy, and emotional reactions. Neuroimaging, pharmacology, and genomics are among the sources of information that have contributed to theories about the pathophysiology of MDD and may lead to truly personalized medicine in the future. PMID:20129000

  9. Studies on Freezing RAM Semen in Absence of Glycerol.

    NASA Astrophysics Data System (ADS)

    Abdelnaby, Abdelhady Abdelhakeam

    1988-12-01

    Glycerol is widely used as a major cryoprotective agent for freezing spermatozoa of almost all species. However, it reduces fertility of sheep inseminated cervically compared with intrauterine insemination. Studies were conducted to develop a method and procedure for freezing ram semen in the absence of glycerol. Post -thaw survival of ram spermatozoa frozen in the absence of glycerol was affected by time and temperature after collection and before dilution and time after dilution and before freezing. Increase in time at 5^ circC before or after dilution and before freezing increased both post-thaw motility and number of cells passing through Sephadex filter. A cold dilution method was developed. Slow cooling of fresh ram semen and diluting at 5^circ C 2-3 hr. after collection, then freezing 1 hr. after dilution improved both post-thaw motility and number of cells passing through Sephadex filter compared with immediate dilution at 30-37^circC after collection and freezing 3-4 hr. later (P < 0.05). An extender was developed to freeze ram semen in the absence of glycerol. An increase in post-thaw motility was obtained when semen was extended in TES titrated with Tris to pH 7.0 (TEST) and osmotic pressure of 375-400 mOsm/kg, containing 25-30% (v/v) egg yolk and 10% (v/v) maltose. A special device (boat) for freezing was constructed to insure the same height of the sample above LN _2 and thus the same freezing rate from freeze to freeze. Freezing of semen in 0.25cc straws at 5-10 cm above LN_2 (73.8 to 49.5 ^circC/min) yielded higher post-thaw motility than the rates resulted from freezing at 15 cm above LN_2 or 1 cm above LN _2. Faster Thawing in 37^ circC water for 30 sec. (7.8^ circC/sec.) increased post-thaw motility compared with slower thawing in 5 or 20^circ C water (P < 0.05). A lambing rate of 52.2% was obtained in one fertility trial conducted with ram semen frozen without glycerol and 17.1% in a second trial. One injection (IM) of 15 mg PGF_{2alpha}/ewe for estrus synchronization during breeding season resulted in higher heat response and lambing rate than two injections given 10 days apart.

  10. Inflammatory cytokine-associated depression.

    PubMed

    Lotrich, Francis E

    2015-08-18

    Inflammatory cytokines can sometimes trigger depression in humans, are often associated with depression, and can elicit some behaviors in animals that are homologous to major depression. Moreover, these cytokines can affect monoaminergic and glutamatergic systems, supporting an overlapping pathoetiology with major depression. This suggests that there could be a specific major depression subtype, inflammatory cytokine-associated depression (ICAD), which may require different therapeutic approaches. However, most people do not develop depression, even when exposed to sustained elevations in inflammatory cytokines. Thus several vulnerabilities and sources of resilience to inflammation-associated depression have been identified. These range from genetic differences in neurotrophic and serotonergic systems to sleep quality and omega-3 fatty acid levels. Replicating these sources of resilience as treatments could be one approach for preventing "ICAD". This article is part of a Special Issue entitled SI: Neuroimmunology in Health And Disease. PMID:25003554

  11. Depression: Should You Consider Antipsychotics?

    MedlinePLUS

    ... some doctors may add an antipsychotic drug. Treating depression with antipsychotic drugs Antipsychotics are drugs that are ... on how well antipsychotic drugs help people with depression. They may help some people, but not all. ...

  12. The Paranoid-Depressive Continuum

    ERIC Educational Resources Information Center

    Johnson, Betty J.

    1977-01-01

    Few investigators have attempted to lay a conceptual base for comparative studies of paranoia and depression within a single general framework. The paranoid-depressive continuum is an attempt to develop such a framework. (Author)

  13. Neediness and depression in women.

    PubMed

    Campos, Rui C; Mesquita, Isabel; Besser, Avi; Blatt, Sidney J

    2014-01-01

    In a 6-month longitudinal design, the authors examined the links between neediness and increases in depressive symptoms in women. Neediness was assessed with the self-report Depressive Experiences Questionnaire (DEQ), supplemented by a projective measure that assessed an important component of dependency, oral dependency, on the Rorschach. Results indicate that neediness correlated significantly with increases in depressive symptoms over the 6 months. Orality interacted with neediness to substantially increase the prediction of increases in depressive symptoms. PMID:24552427

  14. Communication: A simple method for simulation of freezing transitions

    NASA Astrophysics Data System (ADS)

    Orkoulas, G.; Nayhouse, Michael

    2011-05-01

    Despite recent advances, precise simulation of freezing transitions continues to be a challenging task. In this work, a simulation method for fluid-solid transitions is developed. The method is based on a modification of the constrained cell model which was proposed by Hoover and Ree [J. Chem. Phys. 47, 4873 (1967)], 10.1063/1.1701730. In the constrained cell model, each particle is confined in a single Wigner-Seitz cell. Hoover and Ree pointed out that the fluid and solid phases can be linked together by adding an external field of variable strength. High values of the external field favor single occupancy configurations and thus stabilize the solid phase. In the present work, the modified cell model is simulated in the constant-pressure ensemble using tempering and histogram reweighting techniques. Simulation results on a system of hard spheres indicate that as the strength of the external field is reduced, the transition from solid to fluid is continuous at low and intermediate pressures and discontinuous at high pressures. Fluid-solid coexistence for the hard-sphere model is established by analyzing the phase transition of the modified model in the limit in which the external field vanishes. The coexistence pressure and densities are in excellent agreement with current state-of-the-art techniques.

  15. Communication: A simple method for simulation of freezing transitions.

    PubMed

    Orkoulas, G; Nayhouse, Michael

    2011-05-01

    Despite recent advances, precise simulation of freezing transitions continues to be a challenging task. In this work, a simulation method for fluid-solid transitions is developed. The method is based on a modification of the constrained cell model which was proposed by Hoover and Ree [J. Chem. Phys. 47, 4873 (1967)]. In the constrained cell model, each particle is confined in a single Wigner-Seitz cell. Hoover and Ree pointed out that the fluid and solid phases can be linked together by adding an external field of variable strength. High values of the external field favor single occupancy configurations and thus stabilize the solid phase. In the present work, the modified cell model is simulated in the constant-pressure ensemble using tempering and histogram reweighting techniques. Simulation results on a system of hard spheres indicate that as the strength of the external field is reduced, the transition from solid to fluid is continuous at low and intermediate pressures and discontinuous at high pressures. Fluid-solid coexistence for the hard-sphere model is established by analyzing the phase transition of the modified model in the limit in which the external field vanishes. The coexistence pressure and densities are in excellent agreement with current state-of-the-art techniques. PMID:21548664

  16. Seeing fearful body language rapidly freezes the observer's motor cortex.

    PubMed

    Borgomaneri, Sara; Vitale, Francesca; Gazzola, Valeria; Avenanti, Alessio

    2015-04-01

    Fearful body language is a salient signal alerting the observer to the presence of a potential threat in the surrounding environment. Although detecting potential threats may trigger an immediate reduction of motor output in animals (i.e., freezing behavior), it is unclear at what point in time similar reductions occur in the human motor cortex and whether they originate from excitatory or inhibitory processes. Using single-pulse and paired-pulse transcranial magnetic stimulation (TMS), here we tested the hypothesis that the observer's motor cortex implements extremely fast suppression of motor readiness when seeing emotional bodies - and fearful body expressions in particular. Participants observed pictures of body postures and categorized them as happy, fearful or neutral while receiving TMS over the right or left motor cortex at 100-125 msec after picture onset. In three different sessions, we assessed corticospinal excitability, short intracortical inhibition (SICI) and intracortical facilitation (ICF). Independently of the stimulated hemisphere and the time of the stimulation, watching fearful bodies suppressed ICF relative to happy and neutral body expressions. Moreover, happy expressions reduced ICF relative to neutral actions. No changes in corticospinal excitability or SICI were found during the task. These findings show extremely rapid bilateral modulation of the motor cortices when seeing emotional bodies, with stronger suppression of motor readiness when seeing fearful bodies. Our results provide neurophysiological support for the evolutionary notions that emotion perception is inherently linked to action systems and that fear-related cues induce an urgent mobilization of motor reactions. PMID:25835523

  17. Relationship between freezing tolerance and shoot water relations of western red cedar.

    PubMed

    Grossnickle, S C

    1992-10-01

    Freezing tolerance and shoot water relations parameters of western red cedar (Thuja plicata Donn) seedlings were measured every 2 weeks from October 1989 to April 1990. Freezing tolerance, measured by freeze-induced electrolyte leakage, showed seasonal shifts in the temperature causing 50% foliage electrolyte leakage (LT(50)). The LT(50) value was -4 degrees C in October, it decreased to -20 degrees C in February and then increased to -6 degrees C in April. The foliage index of injury at -10 degrees C (II(-10)) also showed seasonal shifts from a high of 98% in October to a low of 18% in February followed by an increase to 82% in April. Osmotic potentials at saturation (Psi(s(sat))) and turgor loss point (Psi(s(tlp))) were, respectively, -1.07 and -1.26 MPa in October, -1.57 and -2.43 MPa in January, and -1.04 and -1.86 MPa in April. Dry weight fraction (DWF) increased and symplastic volume at full turgor (V(o)) decreased during the fall-winter acclimation phase, whereas DWF decreased and V(o) increased during the late winter-spring deacclimation phase. Relationships between seasonal patterns of freezing tolerance and shoot water relations parameters showed that LT(50) and II(-10) decreased linearly as Psi(s(tlp)) and V(o) decreased and DWF increased. There was no discernible difference in the relationship during fall acclimation or spring deacclimation. The freezing dehydration index at -10 degrees C (FDI(-10)) declined from 0.69 in November to 0.41 in February and increased to 0.56 in April. The value of II(-10) decreased linearly as FDI(-10) decreased, although a measurement made on actively growing spring foliage did not fit this relationship. The results indicate that seasonal changes in freezing tolerance of western red cedar are partially due to changes in tissue water content, symplastic volume, passive osmotic adjustment and FDI(-10). PMID:14969948

  18. The molecular neurobiology of depression

    Microsoft Academic Search

    Vaishnav Krishnan; Eric J. Nestler

    2008-01-01

    Unravelling the pathophysiology of depression is a unique challenge. Not only are depressive syndromes heterogeneous and their aetiologies diverse, but symptoms such as guilt and suicidality are impossible to reproduce in animal models. Nevertheless, other symptoms have been accurately modelled, and these, together with clinical data, are providing insight into the neurobiology of depression. Recent studies combining behavioural, molecular and

  19. Adolescent depression: Why more girls?

    Microsoft Academic Search

    Anne C. Petersen; Pamela A. Sarigiani; Robert E. Kennedy

    1991-01-01

    Although there has been evidence for some time of a sex difference in depression, relatively little research has examined the developmental process by which women come to be at greater risk than men for depression. In this paper, the developmental pattern of depressed affect is examined over early and middle adolescence, with a special focus on the patterns of boys

  20. Discovering Endophenotypes for Major Depression

    Microsoft Academic Search

    Gregor Hasler; Wayne C Drevets; Husseini K Manji; Dennis S Charney

    2004-01-01

    The limited success of genetic studies of major depression has raised questions concerning the definition of genetically relevant phenotypes. This paper presents strategies to improve the phenotypic definition of major depression by proposing endophenotypes at two levels: First, dissecting the depressive phenotype into key components results in narrow definitions of putative psychopathological endophenotypes: mood bias toward negative emotions, impaired reward

  1. Depression and insomnia in women

    Microsoft Academic Search

    Andrew D. Krystal

    2004-01-01

    Depression and insomnia are both significantly more prevalent in women than in men. Risks appear linked to fluctuations and transitions in gonadal hormones during various phases of women's lives, with the risk of depression greatest during the period from menarche to menopause. Increased risks of both insomnia and depression also coincide with the late luteal phase of the menstrual cycle,

  2. Lessons from the Great Depression

    Microsoft Academic Search

    Peter Temin

    1989-01-01

    Do events of the 1930s carry a message for the 1990s? Lessons from the Great Depression provides an integrated view of the depression, covering the experience in Britain, France, Germany, and the United States. It describes the causes of the depression, why it was so widespread and prolonged, and what brought about eventual recovery. Peter Temin also finds parallels in

  3. Major Depression and Complicated Grief

    MedlinePLUS

    ... bereavement The grief process Major depression and complicated grief Coping with loss Helping someone who is grieving Grief ... References Previous Topic The grief process Next Topic Coping with loss Major depression and complicated grief Depression It’s common for people to have sadness, ...

  4. Unrecognised depression in general practice

    Microsoft Academic Search

    P Freeling; B M Rao; E S Paykel; L I Sireling; R H Burton

    1985-01-01

    Patients attending their general practitioner were screened and a group with unrecognised major depressive disorder identified. This group was interviewed and the findings compared with those in a group of patients recognised correctly as depressed by their general practitioners. Half of the patients with severe depression screened in their doctors' waiting rooms went unrecognised, and they differed in few ways

  5. Cold-Induced Freezing Tolerance in Arabidopsis1

    PubMed Central

    Wanner, Leslie A.; Junttila, Olavi

    1999-01-01

    Changes in the physiology of plant leaves are correlated with enhanced freezing tolerance and include accumulation of compatible solutes, changes in membrane composition and behavior, and altered gene expression. Some of these changes are required for enhanced freezing tolerance, whereas others are merely consequences of low temperature. In this study we demonstrated that a combination of cold and light is required for enhanced freezing tolerance in Arabidopsis leaves, and this combination is associated with the accumulation of soluble sugars and proline. Sugar accumulation was evident within 2 h after a shift to low temperature, which preceded measured changes in freezing tolerance. In contrast, significant freezing tolerance was attained before the accumulation of proline or major changes in the percentage of dry weight were detected. Many mRNAs also rapidly accumulated in response to low temperature. All of the cold-induced mRNAs that we examined accumulated at low temperature even in the absence of light, when there was no enhancement of freezing tolerance. Thus, the accumulation of these mRNAs is insufficient for cold-induced freezing tolerance. PMID:10364390

  6. Freeze-thaw durability of air-entrained concrete.

    PubMed

    Shang, Huai-Shuai; Yi, Ting-Hua

    2013-01-01

    One of the most damaging actions affecting concrete is the abrupt temperature change (freeze-thaw cycles). The types of deterioration of concrete structures by cyclic freeze-thaw can be largely classified into surface scaling (characterized by the weight loss) and internal crack growth (characterized by the loss of dynamic modulus of elasticity). The present study explored the durability of concrete made with air-entraining agent subjected to 0, 100, 200, 300, and 400 cycles of freeze-thaw. The experimental study of C20, C25, C30, C40, and C50 air-entrained concrete specimens was completed according to "the test method of long-term and durability on ordinary concrete" GB/T 50082-2009. The dynamic modulus of elasticity and weight loss of specimens were measured after different cycles of freeze-thaw. The influence of freeze-thaw cycles on the relative dynamic modulus of elasticity and weight loss was analyzed. The findings showed that the dynamic modulus of elasticity and weight decreased as the freeze-thaw cycles were repeated. They revealed that the C30, C40, and C50 air-entrained concrete was still durable after 300 cycles of freeze-thaw according to the experimental results. PMID:23576906

  7. Metabolic Changes in Avena sativa Crowns Recovering from Freezing

    PubMed Central

    Henson, Cynthia A.; Duke, Stanley H.; Livingston, David P.

    2014-01-01

    Extensive research has been conducted on cold acclimation and freezing tolerance of fall-sown cereal plants due to their economic importance; however, little has been reported on the biochemical changes occurring over time after the freezing conditions are replaced by conditions favorable for recovery and growth such as would occur during spring. In this study, GC-MS was used to detect metabolic changes in the overwintering crown tissue of oat (Avena sativa L.) during a fourteen day time-course after freezing. Metabolomic analysis revealed increases in most amino acids, particularly proline, 5-oxoproline and arginine, which increased greatly in crowns that were frozen compared to controls and correlated very significantly with days after freezing. In contrast, sugar and sugar related metabolites were little changed by freezing, except sucrose and fructose which decreased dramatically. In frozen tissue all TCA cycle metabolites, especially citrate and malate, decreased in relation to unfrozen tissue. Alterations in some amino acid pools after freezing were similar to those observed in cold acclimation whereas most changes in sugar pools after freezing were not. These similarities and differences suggest that there are common as well as unique genetic mechanisms between these two environmental conditions that are crucial to the winter survival of plants. PMID:24675792

  8. Freeze-Thaw Durability of Air-Entrained Concrete

    PubMed Central

    Shang, Huai-Shuai; Yi, Ting-Hua

    2013-01-01

    One of the most damaging actions affecting concrete is the abrupt temperature change (freeze-thaw cycles). The types of deterioration of concrete structures by cyclic freeze-thaw can be largely classified into surface scaling (characterized by the weight loss) and internal crack growth (characterized by the loss of dynamic modulus of elasticity). The present study explored the durability of concrete made with air-entraining agent subjected to 0, 100, 200, 300, and 400 cycles of freeze-thaw. The experimental study of C20, C25, C30, C40, and C50 air-entrained concrete specimens was completed according to “the test method of long-term and durability on ordinary concrete” GB/T 50082-2009. The dynamic modulus of elasticity and weight loss of specimens were measured after different cycles of freeze-thaw. The influence of freeze-thaw cycles on the relative dynamic modulus of elasticity and weight loss was analyzed. The findings showed that the dynamic modulus of elasticity and weight decreased as the freeze-thaw cycles were repeated. They revealed that the C30, C40, and C50 air-entrained concrete was still durable after 300 cycles of freeze-thaw according to the experimental results. PMID:23576906

  9. Levodopa changes the severity of freezing in Parkinson's disease.

    PubMed

    Fietzek, Urban M; Zwosta, Jens; Schroeteler, Frauke E; Ziegler, Kerstin; Ceballos-Baumann, Andres O

    2013-10-01

    Oral levodopa has been proposed to be one of the more effective medications to alleviate freezing of gait, but there is limited data on its efficacy. We evaluated the gait phenomenology of 20 Parkinson's disease patients with freezing of gait before and 60 min after a standardized levodopa dose using a rating scale based on the assumption that festination and akinetic freezing share a common pathophysiology. Levodopa abolished festination and freezing in 20% of patients (p < 0.0001), and reduced the freezing sum score from a median of 15 (IQR 6.75-27.5) to 3.5 (1-11.25), p < 0.001) in all but one of the remainder. Pre-dose ratings correlated with post-dose ratings, in that those patients with lower pre-dose item-scores also showed lower post-dose outcome scores. Levodopa's effect on both festination and akinetic freezing was linear, thereby supporting the concept that festination and freezing are variants on a continuity of episodic gait disorders in PD. PMID:23642712

  10. Systematics of kinetic freeze-out properties in high energy collisions from STAR

    NASA Astrophysics Data System (ADS)

    Kumar, Lokesh

    2014-11-01

    The main aim of the RHIC Beam Energy Scan (BES) program is to explore the QCD phase diagram which includes search for a possible QCD critical point and the phase boundary between QGP and hadronic phase. We report the collision energy and centrality dependence of kinetic freeze-out properties from the measured mid-rapidity (| y | < 0.1) light hadrons (pions, kaons, protons and their anti-particles) for Au + Au collisions at the center-of-mass energy ?{sNN} = 7.7 , 11.5 , 19.6 , 27 , and 39 GeV. The STAR detector, with a large uniform acceptance and excellent particle identification is used in the data collection and analysis. The kinetic freeze-out temperature Tkin and average collective velocity < ? > parameters are extracted from blast-wave fits to the identified hadron spectra and systematically compared with the results from other collision energies including those at AGS, SPS and LHC. It is found that all results fall into an anti-correlation band in the 2-dimensional (Tkin, < ? >) distribution: the largest value of collective velocity and lowest temperature is reached in the most central collisions at the highest collision energy. The energy dependence of these freeze-out parameters is discussed.

  11. Mutagenic effect of freezing on nuclear DNA of Saccharomyces cerevisiae.

    PubMed

    Todorova, T; Pesheva, M; Stamenova, R; Dimitrov, M; Venkov, P

    2012-05-01

    Although fragmentation of DNA has been observed in cells undergoing freezing procedures, a mutagenic effect of sub-zero temperature treatment has not been proved by induction and isolation of mutants in nuclear DNA (nDNA). In this communication we supply evidence for mutagenicity of freezing on nDNA of Saccharomyces cerevisiae cells. In the absence of cryoprotectors, cooling for 2 h at +4°C and freezing for 1 h at -10°C and 16 h at -20°C, with a cooling rate of 3°C/min, resulted in induction of frame-shift and reverse mutations in microsatellite and coding regions of nDNA. The sub-zero temperature exposure also has a strong recombinogenic effect, evidenced by induction of gene-conversion and crossing-over events. Freezing induces mutations and enhances recombination with a frequency equal to or higher than that of methylmethanesulphonate at comparable survival rates. The signals for the appearance of nDNA lesions induced by freezing are detected and transduced by the DNA damage pathway. Extracellular cryoprotectors did not prevent the mutagenic effect of freezing, while accumulation of trehalose inside cells reduced nDNA cryodamage. Freezing of cells is accompanied by generation of high ROS levels, and the oxidative stress raised during the freeze-thaw process is the most likely reason for the DNA damaging effect. Experiments with mitochondrial rho? mutants or scavengers of ROS indicated that mutagenic and recombinogenic effects of sub-zero temperatures can be decreased but not eliminated by reduction of ROS level. The complete protection against cryodamage in nDNA required simultaneous usage of intracellular cryoprotector and ROS scavenger during the freeze-thaw process. PMID:22576810

  12. Sex, Anger and Depression

    ERIC Educational Resources Information Center

    Simon, Robin W.; Lively, Kathryn

    2010-01-01

    A social problem that has preoccupied sociologists of gender and mental health is the higher rate of depression found among women. Although a number of hypotheses about this health disparity between men and women have been advanced, none consider the importance of subjectively experienced anger. Drawing on theoretical and empirical insights from…

  13. [Gender differences in depression].

    PubMed

    Karger, A

    2014-09-01

    Depression is one of the most prevalent and debilitating diseases. In recent years there has been increased awareness of sex- and gender-specific issues in depression. This narrative review presents and discusses differences in prevalence, symptom profile, age at onset and course, comorbidity, biological and psychosocial factors, the impact of sexual stereotyping, help-seeking, emotion regulation and doctor-patient communication. Typically, women are diagnosed with depression twice as often as men, and their disease follows a more chronic course. Comorbid anxiety is more prevalent in women, whereas comorbid alcohol abuse is a major concern in men. Sucide rates for men are between three and five times higher compared with women. Although there are different symptom profiles in men and women, it is difficult to define a gender-specific symptom profile. Socially mediated gender roles have a significant impact on psychosocial factors associated with risk, sickness behavior and coping strategies. In general, too little attention has been paid to the definition and handling of depression and the gender-related requirements it makes on the healthcare system. PMID:25070409

  14. Prenatal depression: Early intervention.

    PubMed

    Anderson, Cheryl A; Lieser, Carol

    2015-07-15

    Frequently undiagnosed and untreated, prenatal depression affects approximately one in four childbearing women. Screening and appropriate management is essential to prevent adverse consequences to both the woman and her unborn infant. Early conversations between the woman and her nurse practitioner are essential to making medical management decisions. PMID:26080296

  15. Depression in young adults

    Microsoft Academic Search

    Daniel J. Smith; Douglas H. R. Blackwood

    2004-01-01

    Affective illnesses may present at any age, but it is becoming clear that patients who suffer from recurrent and severe forms of mood disorder often experience their first episode of illness early in life. The clinical presentation of depression at this stage of life can be atypical and is often complicated by personality difficulties and substance misuse. A significant proportion

  16. The genetics of depression

    Microsoft Academic Search

    C. Perris; H. Perris; U. Ericsson; L. von Knorring

    1982-01-01

    Sixty unipolar (23 male and 37 female) patients and 67 patients (25 male and 42 female) suffering from a neurotic-reactive depressive disorder, consecutively admitted to the Department of Psychiatry of Umeå University have participated in a family study aimed at identifying morbidity risks for psychiatric illnesses among first degree relatives (n=437). Besides the classification of affective disorders used in Umeå

  17. Contrasts between symptoms of summer depression and winter depression.

    PubMed

    Wehr, T A; Giesen, H A; Schulz, P M; Anderson, J L; Joseph-Vanderpool, J R; Kelly, K; Kasper, S; Rosenthal, N E

    1991-12-01

    Epidemiological studies and studies of clinical populations suggest that there are primarily two opposite patterns of seasonally recurring depressions: summer depression and winter depression. In addition, there is preliminary evidence that the two seasonal types of depression may have opposite types of vegetative symptoms. In the present study, we prospectively monitored symptoms of depression in 30 patients with recurrent summer depression and 30 sex-matched patients with recurrent winter depression and compared the symptom profiles of the two groups. Consistent with predictions based on the earlier reports, we found that winter depressives were more likely to have atypical vegetative symptoms, with increased appetite, carbohydrate craving, weight gain and hypersomnia, and that summer depressives were more likely to have endogenous vegetative symptoms, with decreased appetite and insomnia. A cluster analysis performed on the patients' symptom profiles without reference to season of occurrence of their episodes separated 78% of the summer depressives and winter depressives from each other on the basis of their symptoms (chi 2 = 19.29, P less than 0.001). PMID:1791262

  18. Air-Cooled Stack Freeze Tolerance Freeze Failure Modes and Freeze Tolerance Strategies for GenDriveTM Material Handling Application Systems and Stacks Final Scientific Report

    SciTech Connect

    Hancock, David, W.

    2012-02-14

    Air-cooled stack technology offers the potential for a simpler system architecture (versus liquid-cooled) for applications below 4 kilowatts. The combined cooling and cathode air allows for a reduction in part count and hence a lower cost solution. However, efficient heat rejection challenges escalate as power and ambient temperature increase. For applications in ambient temperatures below freezing, the air-cooled approach has additional challenges associated with not overcooling the fuel cell stack. The focus of this project was freeze tolerance while maintaining all other stack and system requirements. Through this project, Plug Power advanced the state of the art in technology for air-cooled PEM fuel cell stacks and related GenDrive material handling application fuel cell systems. This was accomplished through a collaborative work plan to improve freeze tolerance and mitigate freeze-thaw effect failure modes within innovative material handling equipment fuel cell systems designed for use in freezer forklift applications. Freeze tolerance remains an area where additional research and understanding can help fuel cells to become commercially viable. This project evaluated both stack level and system level solutions to improve fuel cell stack freeze tolerance. At this time, the most cost effective solutions are at the system level. The freeze mitigation strategies developed over the course of this project could be used to drive fuel cell commercialization. The fuel cell system studied in this project was Plug Power's commercially available GenDrive platform providing battery replacement for equipment in the material handling industry. The fuel cell stacks were Ballard's commercially available FCvelocity 9SSL (9SSL) liquid-cooled PEM fuel cell stack and FCvelocity 1020ACS (Mk1020) air-cooled PEM fuel cell stack.

  19. Effect of local filtering on freezing phenomena of quantum correlation

    NASA Astrophysics Data System (ADS)

    Karmakar, Sumana; Sen, Ajoy; Bhar, Amit; Sarkar, Debasis

    2015-05-01

    General quantum correlation measures such as quantum discord, one-norm geometric quantum discord exhibit freezing, sudden change, and double sudden change behavior in their decay rates under different noisy channels. Therefore, one may attempt to investigate how the freezing behavior and other dynamical features are affected under application of local quantum operations. In this work, we demonstrate the effect of local filtering on the dynamical evolution of quantum correlations. We have found that using local filtering, one may remove freezing depending upon the filtering parameter.

  20. Effect of local filtering on freezing phenomena of quantum correlation

    NASA Astrophysics Data System (ADS)

    Karmakar, Sumana; Sen, Ajoy; Bhar, Amit; Sarkar, Debasis

    2015-07-01

    General quantum correlation measures such as quantum discord, one-norm geometric quantum discord exhibit freezing, sudden change, and double sudden change behavior in their decay rates under different noisy channels. Therefore, one may attempt to investigate how the freezing behavior and other dynamical features are affected under application of local quantum operations. In this work, we demonstrate the effect of local filtering on the dynamical evolution of quantum correlations. We have found that using local filtering, one may remove freezing depending upon the filtering parameter.

  1. Freeze-out volume of hot dense fireball

    E-print Network

    M. Mishra; C. P. Singh

    2007-09-27

    A thermodynamically consistent excluded volume model is proposed to account for the particle multiplicities obtained from lowest SIS energies to the highest RHIC energies. The chemical freeze-out volumes lying in a slice of one unit of rapidity for pions and kaons are separately inferred from this analysis and the results are compared with the corresponding thermal freeze-out volumes obtained from the Hanbury-Brown Twiss (HBT) pion interferometry. Furthermore, we extract the variations of freeze-out number densities for pions and nucleons with the center-of-mass energy in our model and compare them with the HBT data.

  2. Clarification of Uncertainty in the Triple Point of Water as a Temperature Fixed Point

    Microsoft Academic Search

    Yoshizo Suyama

    1980-01-01

    The triple point of water in sealed glass cells with commonly recommended specifications possesses incomprehensible characteristics, namely a gradual rise of the triple point temperature by about 0.2 mK during the first few days and, in some cells, a gradual depression after the first ten or so hours. This is a source of uncertainty in the triple point of water

  3. Inner ear tissue preservation by rapid freezing: improving fixation by high-pressure freezing and hybrid methods.

    PubMed

    Bullen, A; Taylor, R R; Kachar, B; Moores, C; Fleck, R A; Forge, A

    2014-09-01

    In the preservation of tissues in as 'close to life' state as possible, rapid freeze fixation has many benefits over conventional chemical fixation. One technique by which rapid freeze-fixation can be achieved, high pressure freezing (HPF), has been shown to enable ice crystal artefact-free freezing and tissue preservation to greater depths (more than 40 ?m) than other quick-freezing methods. Despite increasingly becoming routine in electron microscopy, the use of HPF for the fixation of inner ear tissue has been limited. Assessment of the quality of preservation showed routine HPF techniques were suitable for preparation of inner ear tissues in a variety of species. Good preservation throughout the depth of sensory epithelia was achievable. Comparison to chemically fixed tissue indicated that fresh frozen preparations exhibited overall superior structural preservation of cells. However, HPF fixation caused characteristic artefacts in stereocilia that suggested poor quality freezing of the actin bundles. The hybrid technique of pre-fixation and high pressure freezing was shown to produce cellular preservation throughout the tissue, similar to that seen in HPF alone. Pre-fixation HPF produced consistent high quality preservation of stereociliary actin bundles. Optimising the preparation of samples with minimal artefact formation allows analysis of the links between ultrastructure and function in inner ear tissues. PMID:25016142

  4. Inner ear tissue preservation by rapid freezing: Improving fixation by high-pressure freezing and hybrid methods

    PubMed Central

    Bullen, A.; Taylor, R.R.; Kachar, B.; Moores, C.; Fleck, R.A.; Forge, A.

    2014-01-01

    In the preservation of tissues in as ‘close to life’ state as possible, rapid freeze fixation has many benefits over conventional chemical fixation. One technique by which rapid freeze-fixation can be achieved, high pressure freezing (HPF), has been shown to enable ice crystal artefact-free freezing and tissue preservation to greater depths (more than 40 ?m) than other quick-freezing methods. Despite increasingly becoming routine in electron microscopy, the use of HPF for the fixation of inner ear tissue has been limited. Assessment of the quality of preservation showed routine HPF techniques were suitable for preparation of inner ear tissues in a variety of species. Good preservation throughout the depth of sensory epithelia was achievable. Comparison to chemically fixed tissue indicated that fresh frozen preparations exhibited overall superior structural preservation of cells. However, HPF fixation caused characteristic artefacts in stereocilia that suggested poor quality freezing of the actin bundles. The hybrid technique of pre-fixation and high pressure freezing was shown to produce cellular preservation throughout the tissue, similar to that seen in HPF alone. Pre-fixation HPF produced consistent high quality preservation of stereociliary actin bundles. Optimising the preparation of samples with minimal artefact formation allows analysis of the links between ultrastructure and function in inner ear tissues. PMID:25016142

  5. Red blood cell preservation by droplet freezing with polyvinyl pyrrolidone or sucrose/dextrose and by bulk freezing with glycerol

    PubMed Central

    Schmid, Pirmin; Huvard, Michael J.; Lee-Stroka, A. Hallie; Lee, Jae Y.; Byrne, Karen M.; Flegel, Willy A.

    2012-01-01

    Background Red blood cell (RBC) preservation is essential to transfusion medicine. Many blood group reference laboratories need a method to preserve rare blood samples for serologic testing at a later date. This study offers a comparison of three common cryoprotective agents and protocols used today: bulk preservation with glycerol and droplet freezing with sucrose/dextrose (S+D) or polyvinyl pyrrolidone (PVP). Study design and methods Human blood from 14 volunteers was collected and frozen at set intervals over two weeks with PVP, S+D, or glycerol. The frozen RBCs were later thawed and the percentage of surviving RBCs was determined. Detailed protocols and an instructional video are supplied. Results Over a two week period, RBCs preserved with glycerol and thawed with a widely used protocol showed a recovery of 41 ± 16 % (mean ± standard deviation) while those thawed with a modified glycerol protocol showed a recovery of 76 ± 8 %. RBCs preserved by droplet freezing with S+D showed a recovery of 56 ± 11 % while those preserved by droplet freezing with PVP showed a recovery of 85 ± 6 %. Recovery values were similar with ethylenediaminetetraacetic acid (EDTA) or heparin anticoagulants, differing freezing rates, and varying droplet volumes. Conclusion Droplet freezing with PVP offered the greatest recovery. While bulk freezing with glycerol can be effective too, droplet freezing may be a more convenient method overall. It requires less effort to thaw, needs much less storage room, and allows blood group laboratories to be frugal with thawing rare samples. PMID:21790629

  6. Couple Discord and Depression in Couples during Couple Therapy and in Depressed Individuals during Depression Treatment

    ERIC Educational Resources Information Center

    Atkins, David C.; Dimidjian, Sona; Bedics, Jamie D.; Christensen, Andrew

    2009-01-01

    The association between depression and relationship distress as well as the impact of treatment for the one on the other was examined across 2 treatment-seeking samples: individuals seeking treatment for depression (N = 120) and couples seeking marital therapy (N = 134 couples). Although there was a baseline association between depression and…

  7. [Post-traumatic stress, post-traumatic depression and major depressive episode: literature].

    PubMed

    Ducrocq, F; Vaiva, G; Cottencin, O; Molenda, S; Bailly, D

    2001-01-01

    Although they are likely to add their effects, physical and psychic traumata (or traumas) can provoke in different ways the appearance of depressive symptoms sometimes common. Post-traumatic depression, reactional depression, major depressive disorder and post-traumatic stress disorder represent different clinical and nosographic disorders in despite of their occasionally common symptomatic core. Historically, it is interesting to note during the XXth century the true semantic change of the terms of trauma from the somatic field to the psychic sphere. Physical traumatism is often represented by a material shock for the subject and by its organic consequences. It is defined as an event that leaves its mark which itself inflicts and handicaps the vital trajectory of the subject. It primarily comprises brain and rachis injuries, whose evolution is frequently characterized by the occurrence/appearance of a depressive disorder, whose genesis rests on psychological but also neurobiologic and physical arguments. Thus major depressive disorders are often present in the course of various physical traumatisms mainly related to nervous system. In accordance with several studies, the prevalence of major depressive disorders ranges from 25% to 50%. These mood disorders occur in the year which follows the accidental event. Their average time of revelation is estimated at four months and their average duration lies between three and six months. Lastly, although these depressive illnesses present clinical symptoms comparable with those observed in other contexts, some nuances can be raised. Nonetheless, they confine sometimes with true clinical forms depending on the intensity, the form, the circumstances or the consequences of the trauma. Psychic traumatism doesn't have the same profile and rests for much dedicated with the reexperiencing. Thus for some authors, depression illness represents a disorder that occurs after a traumatic event whereas others see a differential diagnosis which exludes or which represents a comorbidity with post-traumatic stress disorder. The review of the literature allows us to emphasize the complexity of the links as well as the clinical and epidemiologic differences between stress disorder and major depressive disorder. From the clinical point of view, the major features of PTSD are articulated around a triad of symptoms. They include the reexperiencing symptoms of the traumatic event such as intrusive memories and recurrent nightmares, the protective reactions such as avoidance of the stimuli associated with the trauma and emotional numbing, and the arousal symptoms such as the startled response and hypervigilance. The complexity of this syndrom is due to the frequent combination of these symptoms with other nonspecific ones. As far as the mood is concerned (the mood symptoms are concerned), the regrouping of some of these symptoms allows the clinician to sometimes releave a depressive symptomatology without being able to assess the DSM diagnosis of major depressive disorder. Epidemiologic studies dealing with the risk of installation of a PTSD after a traumatic event reveal differences in the prevalence depending on the nature of the traumatic events: ranging from 1% in general population to 80% following some situations of extreme and durable psychic suffering. Between both poles, one finds a prevalence ranging between 20 and 50% following other events such as serious accidents, natural disasters or criminal assaults. The clinical features of depressive episodes comorbid or associated with PTSD have some characteristics making it possible to individualize various clinical forms as a function of traumatic event type: asthenic, characterial or with somatic symptoms. According to the majority of authors, the co-occurrence of post-traumatic stress disorder and major depressive disorder is high although differential diagnosis is sometimes difficult. However, conceptual differences remain and two conceptions are distinguished. For some authors, like Bleich and Shalev, there would not be true chronological evo

  8. Prevalence of Depressive Symptoms among University Students in Oman

    PubMed Central

    Al-Busaidi, Zakiya; Bhargava, Kamlesh; Al-Ismaily, Aida; Al-Lawati, Hadia; Al-Kindi, Rahma; Al-Shafaee, Mohammad; Al-Maniri, Abdullah

    2011-01-01

    Objectives To study the prevalence of depressive symptoms and its association with gender, academic year, and college among university students in Oman. Methods A cross-sectional study was conducted among Omani students attending the students’ clinic of the Sultan Qaboos University (SQU). A systematic sampling of students, males and females, from different colleges, who visited the clinic during the study period, was carried out. The self-administered Patient Health Questionnaire (PHQ-9) was used to screen for propensity to depression. Results A total of 481 students participated in the study (243 males and 238 females). Overall, 133 (27.7%) of the participants (66 males and 67 females) had depression of various grades based on the PHQ-9 diagnostic criteria using a cut point of more than 11. Depression score at the cut point of 11 was not statistically associated with gender, college and the academic year. Conclusion Tendency for depression might be a common health problem among college students in Oman attending primary health care facilities. Further research on socio-demographic characteristics and the effect of depression on the academic performance is needed. PMID:22043426

  9. Cortisol awakening response and subsequent depression: prospective longitudinal study

    PubMed Central

    Carnegie, Rebecca; Araya, Ricardo; Ben-Shlomo, Yoav; Glover, Vivette; O’Connor, Thomas G.; O’Donnell, Kieran J.; Pearson, Rebecca; Lewis, Glyn

    2014-01-01

    Background Some studies have found an association between elevated cortisol and subsequent depression, but findings are inconsistent. The cortisol awakening response may be a more stable measure of hypothalamic-pituitary-adrenal function and potentially of stress reactivity. Aims To investigate whether salivary cortisol, particularly the cortisol awakening response, is associated with subsequent depression in a large population cohort. Method Young people (aged 15 years, n = 841) from the Avon Longitudinal Study of Parents and Children (ALSPAC) collected salivary cortisol at four time points for 3 school days. Logistic regression was used to calculate odds ratios for developing depression meeting ICD-10 criteria at 18 years. Results We found no evidence for an association between salivary cortisol and subsequent depression. Odds ratios for the cortisol awakening response were 1.24 per standard deviation (95% CI 0.93-1.66, P = 0.14) before and 1.12 (95% CI 0.73-1.72, P = 0.61) after adjustment for confounding factors. There was no evidence that the other cortisol measures, including cortisol at each time point, diurnal drop and area under the curve, were associated with subsequent depression. Conclusions Our findings do not support the hypothesis that elevated salivary cortisol increases the short-term risk of subsequent depressive illness. The results suggest that if an association does exist, it is small and unlikely to be of clinical significance. PMID:24311550

  10. Therapeutic horticulture in clinical depression: a prospective study.

    PubMed

    Gonzalez, Marianne Thorsen; Hartig, Terry; Patil, Grete Grindal; Martinsen, Egil W; Kirkevold, Marit

    2009-01-01

    Clinically depressed persons suffer from impaired mood and distortion of cognition. This study assessed changes in depression severity and perceived attentional capacity of clinically depressed adults (N=18) during a 12-week therapeutic horticulture program. The Beck Depression Inventory (BDI) and Attentional Function Index (AFI) were administered at baseline, twice during (4 and 8 weeks), and immediately after the intervention (12 weeks), and at a 3-month follow-up. Experiences of being away and fascination related to the intervention were measured at 4, 8, and 12 weeks. The mean BDI score declined 9.7 points from pretest (27.3) to posttest (p < .001) and were clinically relevant (deltaBDI > or =6) for 72% of the cases. The mean AFI score increased 10.2 points from pretest (68.8) to posttest (p = .06). The greatest change in BDI and AFI scores occurred in the initial weeks of the intervention. The reduction in BDI scores remained significant and clinically relevant at the 3-month follow-up (N=16). The decline in depression severity during the intervention correlated strongly with the degree to which the participants found that it captured their attention. Therapeutic horticulture may decrease depression severity and improve perceived attentional capacity by engaging effortless attention and interrupting rumination. PMID:19999748

  11. Adaptation to seasonality and the winter freeze

    PubMed Central

    Preston, Jill C.; Sandve, Simen R.

    2013-01-01

    Flowering plants initially diversified during the Mesozoic era at least 140 million years ago in regions of the world where temperate seasonal environments were not encountered. Since then several cooling events resulted in the contraction of warm and wet environments and the establishment of novel temperate zones in both hemispheres. In response, less than half of modern angiosperm families have members that evolved specific adaptations to cold seasonal climates, including cold acclimation, freezing tolerance, endodormancy, and vernalization responsiveness. Despite compelling evidence for multiple independent origins, the level of genetic constraint on the evolution of adaptations to seasonal cold is not well understood. However, the recent increase in molecular genetic studies examining the response of model and crop species to seasonal cold offers new insight into the evolutionary lability of these traits. This insight has major implications for our understanding of complex trait evolution, and the potential role of local adaptation in response to past and future climate change. In this review, we discuss the biochemical, morphological, and developmental basis of adaptations to seasonal cold, and synthesize recent literature on the genetic basis of these traits in a phylogenomic context. We find evidence for multiple genetic links between distinct physiological responses to cold, possibly reinforcing the coordinated expression of these traits. Furthermore, repeated recruitment of the same or similar ancestral pathways suggests that land plants might be somewhat pre-adapted to dealing with temperature stress, perhaps making inducible cold traits relatively easy to evolve. PMID:23761798

  12. Hot water can freeze faster than cold?!?

    E-print Network

    Monwhea Jeng

    2005-12-29

    We review the Mpemba effect, where intially hot water freezes faster than initially cold water. While the effect appears impossible at first sight, it has been seen in numerous experiments, was reported on by Aristotle, Francis Bacon, and Descartes, and has been well-known as folklore around the world. It has a rich and fascinating history, which culminates in the dramatic story of the secondary school student, Erasto Mpemba, who reintroduced the effect to the twentieth century scientific community. The phenomenon, while simple to describe, is deceptively complex, and illustrates numerous important issues about the scientific method: the role of skepticism in scientific inquiry, the influence of theory on experiment and observation, the need for precision in the statement of a scientific hypothesis, and the nature of falsifiability. We survey proposed theoretical mechanisms for the Mpemba effect, and the results of modern experiments on the phenomenon. Studies of the observation that hot water pipes are more likely to burst than cold water pipes are also described.

  13. Drying a tuberculosis vaccine without freezing.

    PubMed

    Wong, Yun-Ling; Sampson, Samantha; Germishuizen, Willem Andreas; Goonesekera, Sunali; Caponetti, Giovanni; Sadoff, Jerry; Bloom, Barry R; Edwards, David

    2007-02-20

    With the increasing incidence of tuberculosis and drug resistant disease in developing countries due to HIV/AIDS, there is a need for vaccines that are more effective than the present bacillus Calmette-Guérin (BCG) vaccine. We demonstrate that BCG vaccine can be dried without traditional freezing and maintained with remarkable refrigerated and room-temperature stability for months through spray drying. Studies with a model Mycobacterium (Mycobacterium smegmatis) revealed that by removing salts and cryoprotectant (e.g., glycerol) from bacterial suspensions, the significant osmotic pressures that are normally produced on bacterial membranes through droplet drying can be reduced sufficiently to minimize loss of viability on drying by up to 2 orders of magnitude. By placing the bacteria in a matrix of leucine, high-yield, free-flowing, "vial-fillable" powders of bacteria (including M. smegmatis and M. bovis BCG) can be produced. These powders show relatively minor losses of activity after maintenance at 4 degrees C and 25 degrees C up to and beyond 4 months. Comparisons with lyophilized material prepared both with the same formulation and with a commercial formulation reveal that the spray-dried BCG has better overall viability on drying. PMID:17299039

  14. GPR utilization in artificial freezing engineering

    NASA Astrophysics Data System (ADS)

    Song, Lei; Yang, Weihao; Huang, Jiahui; Li, Haipeng; Zhang, Xiaojun

    2013-06-01

    To utilize ground penetrating radar (GPR) in artificial freezing engineering (AFE), the electromagnetic parameters (EMP) of frozen soil were measured using a vector network analyser, which showed that the dielectric permittivity and electric conductivity change abruptly at the boundary between the frozen and the non-frozen soil. Then similarity criteria of GPR model experiments were deduced, and GPR laboratory model experiments and field explorations of AFE were carried out. It was found that for AFE, the GPR travel time and profile characters of anomalies in model experiments were similar to those in field explorations, while the amplitude of GPR signals in laboratory model experiments were much stronger than those in field explorations. Numerical simulations were also implemented to analyse the relationship between model experiments and field explorations, which further told us why we could easily find the targets by GPR in the laboratory but not in field explorations. The outputs showed that GPR could be used to detect the thickness of the frozen wall and to find unfrozen soil defects, even though the amplitude of the reflective signals were much weaker than those of laboratory experiments. The research findings have an important theoretical value for AFE and permafrost region engineering, and the deduced GPR similarity criteria could be widely used in other GPR model experiments.

  15. Adaptation to seasonality and the winter freeze.

    PubMed

    Preston, Jill C; Sandve, Simen R

    2013-01-01

    Flowering plants initially diversified during the Mesozoic era at least 140 million years ago in regions of the world where temperate seasonal environments were not encountered. Since then several cooling events resulted in the contraction of warm and wet environments and the establishment of novel temperate zones in both hemispheres. In response, less than half of modern angiosperm families have members that evolved specific adaptations to cold seasonal climates, including cold acclimation, freezing tolerance, endodormancy, and vernalization responsiveness. Despite compelling evidence for multiple independent origins, the level of genetic constraint on the evolution of adaptations to seasonal cold is not well understood. However, the recent increase in molecular genetic studies examining the response of model and crop species to seasonal cold offers new insight into the evolutionary lability of these traits. This insight has major implications for our understanding of complex trait evolution, and the potential role of local adaptation in response to past and future climate change. In this review, we discuss the biochemical, morphological, and developmental basis of adaptations to seasonal cold, and synthesize recent literature on the genetic basis of these traits in a phylogenomic context. We find evidence for multiple genetic links between distinct physiological responses to cold, possibly reinforcing the coordinated expression of these traits. Furthermore, repeated recruitment of the same or similar ancestral pathways suggests that land plants might be somewhat pre-adapted to dealing with temperature stress, perhaps making inducible cold traits relatively easy to evolve. PMID:23761798

  16. Satellite freeze forecast system: Executive summary

    NASA Technical Reports Server (NTRS)

    Martsolf, J. D. (principal investigator)

    1983-01-01

    A satellite-based temperature monitoring and prediction system consisting of a computer controlled acquisition, processing, and display system and the ten automated weather stations called by that computer was developed and transferred to the national weather service. This satellite freeze forecasting system (SFFS) acquires satellite data from either one of two sources, surface data from 10 sites, displays the observed data in the form of color-coded thermal maps and in tables of automated weather station temperatures, computes predicted thermal maps when requested and displays such maps either automatically or manually, archives the data acquired, and makes comparisons with historical data. Except for the last function, SFFS handles these tasks in a highly automated fashion if the user so directs. The predicted thermal maps are the result of two models, one a physical energy budget of the soil and atmosphere interface and the other a statistical relationship between the sites at which the physical model predicts temperatures and each of the pixels of the satellite thermal map.

  17. Optoacoustic laser monitoring of cooling and freezing of tissues

    SciTech Connect

    Larin, Kirill V; Larina, I V; Motamedi, M; Esenaliev, R O [University of Texas, Medical Branch, Galveston, TX (United States)

    2002-11-30

    Real-time monitoring of cooling and freezing of tissues, cells, and other biological objects with a high spatial and time resolution, which is necessary for selective destruction of cancer and benign tumours during cryotherapy, as well as for preventing any damage to the structure and functioning of biological objects in cryobiology, is considered. The optoacoustic method, based on the measurement and analysis of acoustic waves induced by short laser pulses, is proposed for monitoring the cooling and freezing of the tissue. The effect of cooling and freezing on the amplitude and time profile of acoustic signals generated in real tissues and in a model object is studied. The experimental results indicate that the optoacoustic laser technique can be used for real-time monitoring of cooling and freezing of biological objects with a submillimeter spatial resolution and a high contrast. (laser biology and medicine)

  18. Hydraulic conductivity of geosynthetic clay liners after freeze-thaw

    SciTech Connect

    Hewitt, R.D. [Haley and Aldrich, Inc., Cambridge, MA (United States); Daniel, D.E. [Univ. of Illinois, Urbana, IL (United States)

    1997-04-01

    Hydraulic conductivity tests were performed in large tanks on intact (single panel) and overlapped samples of three geosynthetic clay liners (GCLs) that has been subjected to freeze-thaw cycles. The compressive stress applied to the GCLs (7.6--12.4 kPa) was selected to simulate final cover systems for landfills. Laboratory flexible-wall permeameter tests were also performed. With the exception of one overlapped GCL, all three GCLs withstood three freeze-thaw cycles without a significant change in hydraulic conductivity. An overlapped, geo-textile-encased, stitch-bonded GCL did undergo a 1,000-fold increase in hydraulic conductivity after one freeze-thaw cycle, but the overlapped area contained stitches, which are left off the edges of the full-sized material that is deployed in the field. In general, the tests showed that GCLs can withstand at least three freeze-thaw cycles without significant changes in hydraulic conductivity.

  19. Universality of tip singularity formation in freezing water drops.

    PubMed

    Marín, A G; Enríquez, O R; Brunet, P; Colinet, P; Snoeijer, J H

    2014-08-01

    A drop of water deposited on a cold plate freezes into an ice drop with a pointy tip. While this phenomenon clearly finds its origin in the expansion of water upon freezing, a quantitative description of the tip singularity has remained elusive. Here we demonstrate how the geometry of the freezing front, determined by heat transfer considerations, is crucial for the tip formation. We perform systematic measurements of the angles of the conical tip, and reveal the dynamics of the solidification front in a Hele-Shaw geometry. It is found that the cone angle is independent of substrate temperature and wetting angle, suggesting a universal, self-similar mechanism that does not depend on the rate of solidification. We propose a model for the freezing front and derive resulting tip angles analytically, in good agreement with the experiments. PMID:25126922

  20. Fast hadron freeze-out generator, part II: noncentral collisions

    E-print Network

    N. S. Amelin; R. Lednicky; I. P. Lokhtin; L. V. Malinina; A. M. Snigirev; Iu. A. Karpenko; Yu. M. Sinyukov; I. Arsene; L. Bravina

    2007-12-13

    The fast Monte Carlo procedure of hadron generation developed in our previous work is extended to describe noncentral collisions of nuclei. We consider different possibilities to introduce appropriate asymmetry of the freeze-out hyper-surface and flow velocity profile. For comparison with other models and experimental data we demonstrate the results based on the standard parametrizations of the hadron freeze-out hyper-surface and flow velocity profile assuming either a common chemical and thermal freeze-out or the chemically frozen evolution from chemical to thermal freeze-out. The C++ generator code is written under the ROOT framework and is available for public use at http://uhkm.jinr.ru/

  1. Multifidelity variance reduction for pick-freeze Sobol index estimation

    E-print Network

    Boyer, Edmond

    Multifidelity variance reduction for pick-freeze Sobol index estimation Alexandre Janon March 25 a large sample of evaluations of the output. We propose a variance reduction technique, based and context . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 Variance-reduced estimator

  2. 19. FIRST FLOOR LEVEL BELOW ICE FREEZING TANKS AND LOWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. FIRST FLOOR LEVEL BELOW ICE FREEZING TANKS AND LOWER LEVEL OF ICE DUMP AND LIFT WHERE FROZEN ICE IS BROUGHT INTO STORAGE. - Atlantic Ice & Coal Company, 135 Prince Street, Montgomery, Montgomery County, AL

  3. Condensation and freezing of droplets on superhydrophobic surfaces.

    PubMed

    Oberli, Linda; Caruso, Dean; Hall, Colin; Fabretto, Manrico; Murphy, Peter J; Evans, Drew

    2014-08-01

    Superhydrophobic coatings are reported as promising candidates for anti-icing applications. Various studies have shown that as well as having ultra water repellency the surfaces have reduced ice adhesion and can delay water freezing. However, the structure or texture (roughness) of the superhydrophobic surface is subject to degradation during the thermocycling or wetting process. This degradation can impair the superhydrophobicity and the icephobicity of those coatings. In this review, a brief overview of the process of droplet freezing on superhydrophobic coatings is presented with respect to their potential in anti-icing applications. To support this discussion, new data is presented about the condensation of water onto physically decorated substrates, and the associated freezing process which impacts on the freezing of macroscopic droplets on the surface. PMID:24200089

  4. Fuel Cells Vehicle Systems Analysis (Fuel Cell Freeze Investigation)

    SciTech Connect

    Pesaran, A.; Kim, G.; Markel, T.; Wipke, K.

    2005-05-01

    Presentation on Fuel Cells Vehicle Systems Analysis (Fuel Cell Freeze Investigation) for the 2005 Hydrogen, Fuel Cells & Infrastructure Technologies Program Annual Review held in Arlington, Virginia on May 23-26, 2005.

  5. Hadron-resonance gas at freeze-out: Reminder on the importance of repulsive interactions

    NASA Astrophysics Data System (ADS)

    Begun, V. V.; Ga?dzicki, M.; Gorenstein, M. I.

    2013-08-01

    An influence of the repulsive interactions on matter properties is considered within the excluded volume van der Waals hadron-resonance gas model. Quantitative results are presented for matter at the chemical freeze-out in central nucleus-nucleus collisions at relativistic energies. In particular, it is shown that repulsive interactions connected to the nonzero size of created particles lead to a significant decrease of the collision energy at which the net-baryon density has a maximum. A position of the transition point from baryon-to-meson dominated matter depends on the difference between baryon and meson hard-core radiuses.

  6. The Prevalence and Risk Factors of Paternal Depression from the Antenatal to the Postpartum Period and the Relationships between Antenatal and Postpartum Depression among Fathers in Hong Kong

    PubMed Central

    Koh, Y. W.; Chui, C. Y.; Tang, C. S. K.; Lee, A. M.

    2014-01-01

    Introduction. Despite the fact that maternal perinatal mental health problems have been extensively studied and addressed to be a significant health problem, the literature on paternal perinatal mental health problems is relatively scarce. The present study aims at determining the prevalence of paternal perinatal depression and identifying the risk factors and the relationship between antenatal and postpartum depression. Methodology. 622 expectant fathers were recruited from regional maternal clinics. The expectant fathers were assessed using standardized and validated psychological instruments on 3 time points including early pregnancy, late pregnancy, and six weeks postpartum. Results. Results showed that a significant proportion of expectant fathers manifested depressive symptoms during the perinatal period. Paternal antenatal depression could significantly predict higher level of paternal postpartum depression. Psychosocial risk factors were consistently associated with paternal depression in different time points. Conclusions. The present study points to the need for greater research and clinical attention to paternal depression given that it is a highly prevalent problem and could be detrimental to their spouse and children development. The present findings contribute to theoretical basis of the prevalence and risk factors of paternal perinatal depression and have implications of the design of effective identification, prevention, and interventions of these clinical problems. PMID:24600517

  7. Pharmaceutics Seminar: Excipient Phase Behavior in Freeze-Dried Systems November 1, 2012 Michael Burcusa

    E-print Network

    Thomas, David D.

    Pharmaceutics Seminar: Excipient Phase Behavior in Freeze-Dried Systems November 1, 2012 Michael, they are often formulated as freeze-dried powders [3]. During the freezing step of the lyophilization process designed for freeze-drying, the solution will contain, in addition to the API, a buffer, a lyoprotectant

  8. Mechanisms of deterioration of nutrients. [improved quality of freeze-dried foods

    NASA Technical Reports Server (NTRS)

    Karel, M.; Flink, J. M.

    1978-01-01

    Methods for improving the quality of freeze-dried foods were investigated. Areas discussed include: (1) microstructure of freeze-dried systems, (2) structural changes in freeze-dried systems, (3) artificial food matrices, and (4) osmotic preconcentration to yield improved freeze-dried products.

  9. Composition-dependent freezing nucleation rates for HNO3/H2O aerosols resembling gravity-wave-perturbed stratospheric particles

    NASA Astrophysics Data System (ADS)

    Prenni, Anthony J.; Onasch, Timothy B.; Tisdale, Robert T.; Siefert, Ronald L.; Tolbert, Margaret A.

    1998-11-01

    Laboratory measurements are presented for the freezing kinetics of H2O/HNO3 aerosols over the temperature range of 188-204 K. For 2:1 H2O:HNO3 aerosols crystallizing to NAD we observed a maximum nucleation rate of J = 9.3×109 cm-3 s-1 at 194 K. This temperature is between the glass point of 161 K [Ji et al., 1993] and the melting point of 235.5 K [Ji et al., 1996]. This can be compared to a previous measurement of J = 6.7×109 cm-3 s-1 at 193 K [Disselkamp et al., 1996] and lower temperature measurements of J ? 1010-1012 cm-3 s-1 at 178.8 - 175.8 K [Bertram and Sloan, 1998a]. Measured nucleation rates decrease as the aerosol becomes dilute, but NAD formation is still observable for 2.5:1 H2O:HNO3 at temperatures near 195 K. In contrast, freezing of 3:1 H2O:HNO3 aerosol was not observed for constant temperature experiments throughout this temperature range, yielding an upper limit of J<1.5×109 cm-3 s-1. This is the lowest experimental value determined for 3:1 H2O:HNO3 freezing rates at these temperatures. From the measured freezing rates and knowledge of the free energy of diffusion the average interfacial free energy for NAD in a 2:1 H2O:HNO3 solution was determined to be ? = 25.2 ergs cm-2. A limit for the interfacial free energy was placed on 3:1 H2O:HNO3 particles, for which freezing was not observed. These data imply that if aerosols reach compositions more concentrated than 3:1 H2O:HNO3 in the atmosphere, NAD may play a role in polar stratospheric cloud formation.

  10. Three keys to the radiation of angiosperms into freezing environments.

    PubMed

    Zanne, Amy E; Tank, David C; Cornwell, William K; Eastman, Jonathan M; Smith, Stephen A; FitzJohn, Richard G; McGlinn, Daniel J; O'Meara, Brian C; Moles, Angela T; Reich, Peter B; Royer, Dana L; Soltis, Douglas E; Stevens, Peter F; Westoby, Mark; Wright, Ian J; Aarssen, Lonnie; Bertin, Robert I; Calaminus, Andre; Govaerts, Rafaël; Hemmings, Frank; Leishman, Michelle R; Oleksyn, Jacek; Soltis, Pamela S; Swenson, Nathan G; Warman, Laura; Beaulieu, Jeremy M

    2014-02-01

    Early flowering plants are thought to have been woody species restricted to warm habitats. This lineage has since radiated into almost every climate, with manifold growth forms. As angiosperms spread and climate changed, they evolved mechanisms to cope with episodic freezing. To explore the evolution of traits underpinning the ability to persist in freezing conditions, we assembled a large species-level database of growth habit (woody or herbaceous; 49,064 species), as well as leaf phenology (evergreen or deciduous), diameter of hydraulic conduits (that is, xylem vessels and tracheids) and climate occupancies (exposure to freezing). To model the evolution of species' traits and climate occupancies, we combined these data with an unparalleled dated molecular phylogeny (32,223 species) for land plants. Here we show that woody clades successfully moved into freezing-prone environments by either possessing transport networks of small safe conduits and/or shutting down hydraulic function by dropping leaves during freezing. Herbaceous species largely avoided freezing periods by senescing cheaply constructed aboveground tissue. Growth habit has long been considered labile, but we find that growth habit was less labile than climate occupancy. Additionally, freezing environments were largely filled by lineages that had already become herbs or, when remaining woody, already had small conduits (that is, the trait evolved before the climate occupancy). By contrast, most deciduous woody lineages had an evolutionary shift to seasonally shedding their leaves only after exposure to freezing (that is, the climate occupancy evolved before the trait). For angiosperms to inhabit novel cold environments they had to gain new structural and functional trait solutions; our results suggest that many of these solutions were probably acquired before their foray into the cold. PMID:24362564

  11. Entropy production at freeze-out from dissipative fluids

    E-print Network

    E. Molnar

    2007-09-17

    Entropy production due to shear viscosity during the continuous freeze-out of a longitudinally expanding dissipative fluid is addressed. Assuming the validity of the fluid dynamical description during the continuous removal of interacting matter we estimated a small entropy production as function of the freeze-out duration and the ratio of dissipative to non-dissipative quantities in case of a relativistic massless pion fluid.

  12. Freeze concentration of dairy products Phase 2. Final report

    SciTech Connect

    Best, D.E.; Vasavada, K.C.

    1993-09-01

    An efficient, electrically driven freeze concentration system offers potential for substantially increasing electricity demand while providing the mature dairy industry with new products for domestic and export markets together with enhanced production efficiencies. Consumer tests indicate that dairy products manufactured from freeze-concentrated ingredients are either preferred or considered equivalent in quality to fresh milk-based products. Economic analyses indicate that this technology should be competitive with thermal evaporation processes on a commercial basis.

  13. Supercooling and Freezing of HNO3\\/H2O Aerosols

    Microsoft Academic Search

    Dustin Dickens

    2000-01-01

    Abstract The freezing kinetics of binary nitric acid\\/water aerosols is of fundamental,importance to the modelling of polar stratospheric clouds and the role they in ozone depletion over the Arctic\\/Antarcticregions. Cirrus clouds are also often composed of nitric acid solutions, hence an understandingof freezing process in these aerosols also aids in modelling the earth’s radiation budget and global warming. This thesis

  14. Chloroplast structure of Cyanidium caldarium shown by freeze-substitution

    Microsoft Academic Search

    Katsumi Ueda; Yukie Chida

    1987-01-01

    The freeze-substituted chloroplast in Cyanidium caldarium was observed by electron microscopy. Double envelope membranes could be clearly seen. Phycobilisomes were much better fixed by freeze-substitution than by chemical fixation. They appeared as slender cords in contrast to the disk or hemispherical shapes assumed by image subjected to chemical fixation. The arrangement of the phycobilisome-cords on the thylakoid was in a

  15. The Kimberley Assessment of Depression of Older Indigenous Australians: Prevalence of Depressive Disorders, Risk Factors and Validation of the KICA-dep Scale

    PubMed Central

    Almeida, Osvaldo P.; Flicker, Leon; Fenner, Stephen; Smith, Kate; Hyde, Zoe; Atkinson, David; Skeaf, Linda; Malay, Roslyn; LoGiudice, Dina

    2014-01-01

    Objective This study aimed to develop a culturally acceptable and valid scale to assess depressive symptoms in older Indigenous Australians, to determine the prevalence of depressive disorders in the older Kimberley community, and to investigate the sociodemographic, lifestyle and clinical factors associated with depression in this population. Methods Cross-sectional survey of adults aged 45 years or over from six remote Indigenous communities in the Kimberley and 30% of those living in Derby, Western Australia. The 11 linguistic and culturally sensitive items of the Kimberley Indigenous Cognitive Assessment of Depression (KICA-dep) scale were derived from the signs and symptoms required to establish the diagnosis of a depressive episode according to the DSM-IV-TR and ICD-10 criteria, and their frequency was rated on a 4-point scale ranging from ‘never’ to ‘all the time’ (range of scores: 0 to 33). The diagnosis of depressive disorder was established after a face-to-face assessment with a consultant psychiatrist. Other measures included sociodemographic and lifestyle factors, and clinical history. Results The study included 250 participants aged 46 to 89 years (mean±SD?=?60.9±10.7), of whom 143 (57.2%) were women. The internal reliability of the KICA-dep was 0.88 and the cut-point 7/8 (non-case/case) was associated with 78% sensitivity and 82% specificity for the diagnosis of a depressive disorder. The point-prevalence of a depressive disorder in this population was 7.7%; 4.0% for men and 10.4% for women. Heart problems were associated with increased odds of depression (odds ratio?=?3.3, 95% confidence interval?=?1.2,8.8). Conclusions The KICA-dep has robust psychometric properties and can be used with confidence as a screening tool for depression among older Indigenous Australians. Depressive disorders are common in this population, possibly because of increased stressors and health morbidities. PMID:24740098

  16. Approaching threats elicit a freeze-like response in humans.

    PubMed

    Sagliano, Laura; Cappuccio, Angela; Trojano, Luigi; Conson, Massimiliano

    2014-02-21

    Freezing is one of the most widely recognized defensive reactions to approaching threats in animals. Here we tested whether the same stimuli can elicit freeze-like responses in healthy humans as well. We used a modified version of the two-frame apparent motion paradigm, in which both size and location of a stimulus within a background were manipulated; by these means, participants perceived the stimuli as approaching or receding. In Experiment 1, we showed that implicitly processed approaching threats (e.g., spiders or snakes) elicited a stronger freeze-like response (operationalized as slower reaction times) with respect to receding threats; freezing was significantly related to higher levels of participants' state anxiety. In Experiment 2, approaching/threatening animals were explicitly judged as more threatening than receding ones. Finally, in two further control experiments we observed that the same manipulation of stimuli's size and location, but in absence of apparent motion, did not affect freezing (Experiment 3) or explicit threat judgements (Experiment 4). The present findings demonstrated that approaching threats are critical to elicit freezing in humans, in line with animals' behaviour. PMID:24373990

  17. Freezing of barley studied by infrared video thermography.

    PubMed

    Pearce, R S; Fuller, M P

    2001-01-01

    Freezing of barley (Hordeum vulgare), Hordeum murinum, and Holcus lanatus was studied using infrared video thermography. In the field, ice could enter H. lanatus leaves through hydathodes. In laboratory tests with barley, initially 0.4% of the leaf water froze, spreading in alternate strips of high and low freezing intensity longitudinally at 1 to 4 cm s(-1), and simultaneously spreading laterally at 0.3 cm s(-1). Similar results were obtained in the field with H. lanatus. A distinct second, more intense, freezing event spread slowly from the margins of the leaves toward the midrib. Organs of uprooted barley tested in the laboratory froze in this order: nucleated leaf, roots, older leaves, younger leaves, and secondary tillers. When ice spread from one leaf to the rest of the plant the crown delayed spread to the roots and other leaves. There was a longer delay above than below -2 degrees C, helping to protect the crown from freezing during mild frosts. Initial spread of freezing was not damaging. However, the initial spread is a prerequisite for the second freezing event, which can cause damage. The route of the initial spread of ice may be extracellular, drawing water from more gel-like parts of the cell wall. PMID:11154332

  18. Review: freeze concentration technology applied to dairy products.

    PubMed

    Sánchez, J; Hernández, E; Auleda, J M; Raventós, M

    2011-02-01

    Freeze concentration is a process of concentrating liquid products by freezing the water content and subsequently removing the so-formed ice crystals from the food system. In dairy processing, this technology offers the advantage of minimizing the heat abuse of sensitive milk components, such as proteins and flavors. It thus provides an opportunity for producing dairy ingredients with enhanced functional and organoleptic qualities. By freeze concentration, skim milk has been concentrated up to 40 wt% total solids (TS) and whole milk up to 44 wt% TS. Lactose and lipids are more concentrated in the ice fraction than in the concentrated fraction. Proteins (casein and whey protein) decrease the ice growth rate and the high viscosity is a limiting factor for the freeze concentration of both skim milk and whole milk. In this study, the most important studies relating to the suspension, block and layer freeze concentration of milk are summarized, analyzing results and indicating how freeze concentration process efficiency of dairy products can be improved. PMID:21364040

  19. Freeze avoidance: a dehydrating moss gathers no ice.

    PubMed

    Lenné, Thomas; Bryant, Gary; Hocart, Charles H; Huang, Cheng X; Ball, Marilyn C

    2010-10-01

    Using cryo-SEM with EDX fundamental structural and mechanical properties of the moss Ceratodon purpureus (Hedw.) Brid. were studied in relation to tolerance of freezing temperatures. In contrast to more complex plants, no ice accumulated within the moss during the freezing event. External ice induced desiccation with the response being a function of cell type; water-filled hydroid cells cavitated and were embolized at -4 °C while parenchyma cells of the inner cortex exhibited cytorrhysis, decreasing to ? 20% of their original volume at a nadir temperature of -20 °C. Chlorophyll fluorescence showed that these winter acclimated mosses displayed no evidence of damage after thawing from -20 °C while GCMS showed that sugar concentrations were not sufficient to confer this level of freezing tolerance. In addition, differential scanning calorimetry showed internal ice nucleation occurred in hydrated moss at ?-12 °C while desiccated moss showed no evidence of freezing with lowering of nadir temperature to -20 °C. Therefore the rapid dehydration of the moss provides an elegantly simple solution to the problem of freezing; remove that which freezes. PMID:20525002

  20. Freeze concentration of dairy products, Phase 1: Final report

    SciTech Connect

    Luksas, A.; Ahmed, S.; Johnson, T.A.

    1989-03-01

    The objective of this study was to explore freeze concentration as a process to replace thermal evaporation in the dairy industry. The goals of the study were to save energy by converting concentration processes to an efficient, electrically powered, refrigeration system, and to create higher quality and innovative products that might bring new life to a nature dairy market. A small freeze concentration pilot plant was used to concentrate products for quality comparisons, for physical and chemical analytical determinations, and to discover any equipment/product attributes or limitations. Data was correlated to compare operating economics of freeze concentrations superior to the fresh feedstock in sensory and functionality tests upon reconstitution. Laboratory testing showed equal or superior quality in resulting spray dried powders from freeze concentrates. Freeze concentration was shown to be economically competitive with thermal processes and second generation freezing technology is projected to produce a substantially less expensive product and offer other advantages over current thermally produced goods. 31 figs., 14 tabs.

  1. [Depression in cardiac patients undergoing rehabilitation--a study for investigating the correlations between depression and occupational groups].

    PubMed

    Kittel, J; Wamper, U; Hinz, A; Schwarz, R; Karoff, M

    2003-06-01

    The results of many studies show that physical recovery and social integration of cardiac patients are negatively influenced by a persistent depressive disorder. For this reason issues of occupational integration should be considered from this point of view, too. Correlations between various occupational groups and depression were investigated with 907 cardiac patients at the beginning and at the end of a follow-up treatment. The results were compared to those for 756 persons in corresponding age groups from the general population. We found that at the beginning of rehabilitation the depression values of the HADS did not show any significant differences between the various occupational groups, however, their values were significantly higher than those found in the general population. During rehabilitation the HADS values decreased significantly. At the end of rehabilitation, unskilled and semi-skilled workers had significantly higher depression values than skilled workers and persons in higher positions. Consequences for medical rehabilitation are discussed. PMID:12813653

  2. Glucocorticoids and depression

    Microsoft Academic Search

    Thomas Steckler; Florian Holsboer; Johannes M. H. M. Reul

    1999-01-01

    Depression has been associated with impaired mineralocorticoid receptor function, restrained glucocorticoid receptor feedback at the level of the hypothalamic–pituitary–adrenal (HPA) axis, raised cortisol level and increased corticotropin-releasing factor activity, which may act in concert to induce the signs and symptoms of the disorder. Pre-clinical and clinical evidence suggests that both genetic and environmental factors contribute to the development of these

  3. The association between depression and chronic kidney disease and mortality among patients hospitalized with congestive heart failure

    Microsoft Academic Search

    S. Susan Hedayati; Wei Jiang; Christopher M. O’Connor; Maragatha Kuchibhatla; K. Ranga Krishnan; Michael S. Cuffe; Michael A. Blazing; Lynda A. Szczech

    2004-01-01

    Background: The point prevalence of depression and its relationship to poor outcomes among patients with chronic kidney disease (CKD) has not been fully characterized. Methods: We performed a secondary analysis of a prospective cohort of 374 patients admitted with congestive heart failure between March 1, 1997 and June 30, 1998, to investigate the point prevalence of depression among patients with

  4. Depressive rumination alters cortisol decline in Major Depressive Disorder.

    PubMed

    LeMoult, Joelle; Joormann, Jutta

    2014-07-01

    Depressive rumination - a central characteristic of Major Depressive Disorder (MDD) - is a maladaptive emotion regulation strategy that prolongs sad mood and depressive episodes. Considerable research demonstrates the emotional and behavioral consequences of depressive rumination, yet few studies investigate its effect on neuroendocrine functioning. The current study examined the effect of an emotion regulation manipulation on the trajectory of cortisol concentrations among individuals with MDD and healthy controls (CTL). Sadness was induced via forced failure. Participants then were randomly assigned to a depressive rumination or distraction emotion regulation induction. MDDs in the rumination condition exhibited less cortisol decline compared to MDDs in the distraction condition and compared to CTLs in either condition. Findings suggest that depressive rumination alters the trajectory of cortisol secretion in MDD and may prolong cortisol production. Results thereby provide important insights into the interaction of biological and psychological factors through which distress contributes to MDD. PMID:24835412

  5. Managing bipolar depression.

    PubMed

    Pary, Raymond; Matuschka, Paul R; Lewis, Susan; Lippmann, Steven

    2006-02-01

    What should the clinician do when confronted with a patient who has depressive symptoms? Seek the proper diagnosis. Question the patient about depressive symptoms over a two-week course that interferes with social and/or occupational functioning. Determine if there is any history of mania or hypomania. Information from a significant other is extremely useful as well. Coexisting diagnoses, such as substance abuse, posttraumatic stress disorder, or medical conditions, must be ruled in or out. It is critical to include a suicide risk assessment in the evaluation. Lithium is still the gold standard for bipolar patients with its suicide preventative effects. Lamotrigine appears to have the advantage of efficacy against bipolar depression without high risk for inducing mania. Experts recommend that a mood stabilizer be used in combination with antidepressants. The tricyclic antidepressants and the monoamine oxidase inhibitors appear to have the highest risk for mania and are best avoided. Atypical antipsychotic medications are best utilized for psychotic symptoms and as adjuncts to existing antidepressants. Cognitive behavioral therapy may complement pharmacotherapy. PMID:21103153

  6. Maladaptive Perfectionism and Ineffective Coping as Mediators between Attachment and Future Depression: A Prospective Analysis

    ERIC Educational Resources Information Center

    Wei, Meifen; Heppner, P. Paul; Russell, Daniel W.; Young, Shannon K.

    2006-01-01

    This study used a longitudinal design to examine whether maladaptive perfectionism and ineffective coping served as 2 mediators of the relation between adult attachment and future depression. Data were collected from 372 undergraduates at 2 time points. Results indicated that (a) the impact of attachment on future depression was mediated through…

  7. Depression and suicidal ideation in college students: a preliminary study of campus variables.

    PubMed

    Lester, David

    2013-02-01

    In a sample of 80 undergraduates, variables associated with the undergraduate experience (such as transfer student status, grade point average, working, and belonging to a fraternity/sorority) were not significantly associated with measures of depression, mania, or suicidal ideation. Students living on campus were more depressed and suicidal than those living with their parents. PMID:23654031

  8. A positive correlation between self-ratings of depression and laboratory-measured aggression

    Microsoft Academic Search

    James M. Bjork; Donald M. Dougherty; F. Gerard Moeller

    1997-01-01

    Aggression and depressive symptoms have been linked using self-rating scales as measures of aggression. In order to study this relationship using an objective measure of aggression, we studied normal controls (42 women and 23 men) with the Point Subtraction Aggression Paradigm (PSAP) and the Beck Depression Inventory (BDI). There was a significant positive correlation (r = 0.442, P = 0.003)

  9. Early Adolescent Depressive Mood: Direct and Indirect Effects of Attributional Styles and Coping

    ERIC Educational Resources Information Center

    Chan, Siu Mui

    2012-01-01

    The present study used a cross-sectional survey design to examine how adolescent depressive mood was related to attributional styles and coping strategies with a sample of 326 youths (aged 8-14 years). With the cutting point adopted in the West, 20.9% of the current sample reported depressive symptoms. Regression analysis results show that, with…

  10. Teacher Support Mediates Concurrent and Longitudinal Associations between Temperament and Mild Depressive Symptoms in Sixth Grade

    ERIC Educational Resources Information Center

    Moritz Rudasill, Kathleen; Pössel, Patrick; Winkeljohn Black, Stephanie; Niehaus, Kate

    2014-01-01

    The combination of changes occurring at the transition to middle school may be a catalyst for the onset of depressive symptoms, yet teacher support at this transition is protective. Research points to certain temperamental traits as risk factors for developing depressive symptoms. This study examines student reports of teacher support and teacher…

  11. Ultrastructural immunolocalization of polyamines in HeLa cells subjected to fast-freezing fixation and freeze substitution

    Microsoft Academic Search

    A. M. Roch; Marie Thérèse Nicolas; Gérard Quash

    1997-01-01

    Polyamines have been localized at the ultrastructural level in HeLa cells subjected first to fast-freezing fixation (FFF)-freeze\\u000a substitution (FS) and then to an immunocytochemical method combining anti-polyamine antibodies and immunogold labelling. Polyamines\\u000a were found in both the cytoplasm and the nucleus and, in the latter, particularly over the dense chromatin area. To our knowledge,\\u000a this is the first example of

  12. Drying of Fennel Plants: Oven, Freeze Drying, Effect of Freeze-Drying Time, and Use of Biopolymers

    Microsoft Academic Search

    Chryssavgi Gardeli; Vasiliki Evageliou; Christoforos Poulos; Stavrianos Yanniotis; Michael Komaitis

    2010-01-01

    Fennel plants were oven and freeze dried. The influence of freeze-drying time on the concentration of the two main components, trans-anethole and isoanethole, of its essential oil was evaluated. Drying time up to 15 h led to 50% reduction of moisture content with minor increase in volatile losses, whereas drying time greater than 15 h resulted in a dried product with an

  13. Lower urinary tract symptoms and erectile dysfunction associated with depression among Japanese patients with late-onset hypogonadism symptoms.

    PubMed

    Takao, Tetsuya; Tsujimura, Akira; Okuda, Hidenobu; Yamamoto, Keisuke; Fukuhara, Shinichiro; Matsuoka, Yasuhiro; Miyagawa, Yasushi; Nonomura, Norio; Okuyama, Akihiko

    2011-06-01

    The aim of this study was to investigate the relation between lower urinary tract symptoms (LUTS), erectile dysfunction (ED) and depression in Japanese patients with late-onset hypogonadism (LOH) symptoms. The study comprised 87 Japanese patients with LOH symptoms (>27 points on the Aging Males Symptoms Scale). Thirty-four patients were diagnosed as having depression and the remaining 53 patients were diagnosed as not having depression by the Mini International Neuropsychiatric Interview. We compared the International Index of Erectile Function (IIEF) 5, International Prostate Symptom Score (IPSS), IPSS quality-of-life (QOL) index, King's Health Questionnaire (KHQ), endocrinological data, and free uroflow study between depression and non-depression patients and performed multiple logistic regression analysis. IIEF5 scores of depression patients were significantly lower than those of non-depression patients. In KHQ, only the category of general health perceptions was significantly higher in depression patients than non-depression patients. However, IPSS, QOL index, and endocrinological and uroflowmetric data showed no significant difference between the groups. Multiple logistic regression analysis revealed moderate and severe ED to be risk factors for depression. However, LUTS are not related to depression. Moderate and severe ED is correlated with depression, whereas LUTS are not related to depression in Japanese LOH patients. PMID:20828247

  14. On the representation of immersion and condensation freezing in cloud models using different nucleation schemes

    NASA Astrophysics Data System (ADS)

    Ervens, B.; Feingold, G.

    2012-07-01

    Ice nucleation in clouds is often observed at temperatures >235 K, pointing to heterogeneous freezing as a predominant mechanism. Many models deterministically predict the number concentration of ice particles as a function of temperature and/or supersaturation. Several laboratory experiments, at constant temperature and/or supersaturation, report heterogeneous freezing as a stochastic, time-dependent process that follows classical nucleation theory; this might appear to contradict deterministic models that predict singular freezing behavior. We explore the extent to which the choice of nucleation scheme (deterministic/stochastic, single/multiple contact angles ?) affects the prediction of the fraction of frozen ice nuclei (IN) and cloud evolution for a predetermined maximum IN concentration. A box model with constant temperature and supersaturation is used to mimic published laboratory experiments of immersion freezing of monodisperse (800 nm) kaolinite particles (~243 K), and the fitness of different nucleation schemes. Sensitivity studies show that agreement of all five schemes is restricted to the narrow parameter range (time, temperature, IN diameter) in the original laboratory studies, and that model results diverge for a wider range of conditions. The schemes are implemented in an adiabatic parcel model that includes feedbacks of the formation and growth of drops and ice particles on supersaturation during ascent. Model results for the monodisperse IN population (800 nm) show that these feedbacks limit ice nucleation events, often leading to smaller differences in number concentration of ice particles and ice water content (IWC) between stochastic and deterministic approaches than expected from the box model studies. However, because the different parameterizations of ? distributions and time-dependencies are highly sensitive to IN size, simulations using polydisperse IN result in great differences in predicted ice number concentrations and IWC between the different schemes. The differences in IWC are mostly due to the different temperatures of the onset of freezing in the nucleation schemes that affect the temporal evolution of the ice number concentration. The growth rates of ice particles are not affected by the choice of the nucleation scheme, which leads to very similar particle sizes. Finally, since the choice of nucleation scheme determines the temperature range over which ice nucleation occurs, at habit-prone temperatures (~253 K), there is the potential for variability in the initial inherent growth ratio of ice particles, which can cause amplification or reduction in differences in predicted IWC.

  15. Investigation of Microcrystalline Cellulose as Ice Nucleus in Immersion Freezing Processes

    NASA Astrophysics Data System (ADS)

    Häusler, Thomas; Khaybulkina, Evgeniya; Felgitsch, Laura; Bichler, Magdalena; Grothe, Hinrich

    2015-04-01

    Aerosol-cloud interactions play an important role in earth's radiation balance. Aerosol particles act as cloud condensation nuclei for liquid droplets and/or as ice nuclei for the formation of ice particles. Previous research in our group has been related to biological ice nucleation.1-3 Here, we present a proxy for many biological macromolecular substances, i.e. microcrystalline cellulose. Due to the chemical convenience of cellulose compared to other biological ice nuclei, basic, but still unknown ice nucleation mechanisms can be investigated. Cellulose is a polysaccharide consisting of a linear chain of several hundred to many thousands of ?(1?4) linked D-glucose units. It is an important structural element of the primary cell wall of green plants, many forms of algae and the oomycetes. Several types of microcrystalline cellulose were analysed and investigated due to their physico-chemical properties. Immersion freezing experiments were carried out in a unique reaction gadget. In this device a water-in-oil suspension (with the cellulose suspended in the aqueous phase) was cooled till the freezing point and was observed through a microscope. The results of the immersion freezing experiments of the different cellulose types showed variable ice nucleation activities depending on their morphology (e.g. particle size) and their concentration. Further analysis methods as scanning electron microscopy (SEM) and small angle X-ray scattering (SAX) were carried out to entirely describe the cellulose and their ice nucleation activity. [1] S.Augustin, H. Wex, D. Niedermeier, B. Pummer, H.Grothe, S. Hartmann, L. Tomsche, T. Clauss, J. Voigtländer, K. Ingatius, and F. Stratmann. Immersion freezing of birch pollen washing water. Atmospheric Chemistry Physics 2013, 13, 10989-11003 [2] B. Pummer, L. Atanasova, H. Bauer, H. Bernardi, I. S. Druzhinina, J. Froehlich-Nowoisky, H. Grothe. Spores of many common airborne fungi reveal no ice nucleation activity in oil immersion freezing experiments. Biogeosciences 2013, 10, 8083- 8091 [3] B. Pummer, H. Baue, J. Bernardi, S. Bleicher, H. Grothe. Suspendable macromolecules are responsible for ice nucleation activity of birch and conifer pollen. Atmospheric Chemistry Physics 2012, 12, 2541-2550

  16. Thermodynamical effects accompanied freezing of two water layers separated by sea ice sheet

    NASA Astrophysics Data System (ADS)

    Bogorodsky, Petr; Marchenko, Aleksey

    2014-05-01

    The process of melt pond freezing is very important for generation of sea ice cover thermodynamic and mass balance during winterperiod. However, due to significant difficulties of field measurements the available data of model estimations still have no instrumental confirmation. In May 2009 the authors carried out laboratory experiment on freezing of limited water volume in the University Centre in Svalbard ice tank. In the course of experiment fresh water layer of 27.5 cm thickness at freezing point poured on the 24 cm sea ice layer was cooled during 50 hours at the temperature -10º C and then once again during 60 hours at -20º C. For revealing process typical characteristics the data of continuous measurements of temperature and salinity in different phases were compared with data of numerical computations obtained with thermodynamic model which was formulated in the frames of 1-D equation system (infinite extension of water freezing layer) and adapted to laboratory conditions. The known surprise of the experiment became proximity of calculated and measured estimates of process dynamics that confirmed the adequacy of the problem mathematical statement (excluding probably process finale stage). This effect can be explained by formation of cracks on the upper layer of ice at sharp decreases of air temperature, which temporary compensated hydrostatic pressure growth during freezing of closed water volume. Another compensated mechanism can be migration of brine through the lower layer of ice under influence of vertical pressure gradient and also rejection of gas dissolved in water which increased its compressibility. During 110 hours cooling thickness of water layer between ice layers reduced approximately to 2 cm. According to computations this layer is not chilled completely but keeps as thin brine interlayer within ice body whose thickness (about units of mm) is determined by temperature fluctuations of cooled surface. Nevertheless, despite good coincidence of experimental and model estimates the question of existence of liquid phase under actual conditions is still open and can be clarified in a continuous laboratory experiment. This work was supported by Russian Foundation for Basic Research (Project # 14-05-00677).

  17. Internet confessions of postpartum depression.

    PubMed

    Kantrowitz-Gordon, Ira

    2013-12-01

    Women with postpartum depression may suffer in silence due to the stigma of depression and failed motherhood. It is important to consider how mothers are able to talk about postpartum depression and what strategies they use. Foucault's idea that confession is a widespread technique for producing truth in Western societies was tested through discourse analysis of posts on an Internet forum for women with postpartum depression. The Internet forum showed women's use of confessionary language and self-judgments as well as their sense of disconnected mothering, shame, and disembodiment. Discourses of depression included the good mother, biomedical illness, and social dysfunction. Findings have implications for creating safe spaces for helping mothers with postpartum depression. PMID:24274243

  18. Triple point determinations of monomethylhydrazine and nitrogen tetroxide, 2.2 percent by weight nitric oxide

    NASA Technical Reports Server (NTRS)

    Smith, Irwin D.; Dhooge, Patrick M.

    1977-01-01

    A series of tests was performed to ascertain the triple points of monomethylhydrazine and nitrogen tetroxide. A laboratory method indicated a triple point for monomethylhydrazine, but tests in a large vacuum chamber indicated that a triple point does not occur in spacelike conditions because the mono-methylhydrazine tends to supercool. Instead, an effective freezing point (with agitation) was obtained. New experimental values for liquid monomethylhydrazine vapor pressure were determined for temperatures from 275.2 to 207.6 K. The values were used to derive vapor pressure equations. Tentative values were obtained for the effective freezing point of nitrogen tetroxide spacelike conditions.

  19. Bipolar II Depression with Melancholic Features

    Microsoft Academic Search

    Franco Benazzi

    2000-01-01

    Bipolar II depression with melancholic features has been understudied. The aims of the present study were to find the prevalence of melancholic features in bipolar II depression and in unipolar depression, and to compare melancholic with nonmelancholic bipolar II\\/ unipolar depression in private practice. One hundred and sixty two consecutive unipolar and bipolar II depressed outpatients were interviewed with the

  20. Physiological signal analysis for patients with depression

    Microsoft Academic Search

    Yen-Ting Chen; I-Chung Hung; Min-Wei Huang; Chun-Ju Hou; Kuo-Sheng Cheng

    2011-01-01

    Depression is a common and serious mental disorder. About 1.9 million people in Taiwan are identified as having depression. There is a trend of increase of the prevalence of depression, three times more depressed persons within the past six years. A few patients with depression were in treatment. Therefore, an available algorithm will be build to measure the neurophysiology of

  1. Adult attachment style and vulnerability to depression

    Microsoft Academic Search

    Barbara Murphy; Glen W. Bates

    1997-01-01

    The present study examined the role of adult attachment styles in differentiating ‘depressed’ and ‘non-depressed’ college students, and the association between attachment styles and the depressive personality vulnerabilities, sociotropy and autonomy. High scores on the fearful and, to a lesser extent, preoccupied attachment scales were associated with higher levels of depression, highlighting negative self-representation as a key factor in depression.

  2. Attentional processes in depressive disorders

    Microsoft Academic Search

    Rick E. Ingram; Ann E. Lumry; Debra Cruet; William Sieber

    1987-01-01

    Theory and research in depression have recently emphasized that self-focused attention may be an important cognitive aspect of this disorder. Although previous research has demonstrated a relationship between self-focused attention and subclinical depression, empirical studies to date have not examined the occurrence of this process in clinically depressed individuals. Using a measure of state self-focused attention frequently employed in social-cognitive

  3. IMMUNITY, AGING, AND GERIATRIC DEPRESSION

    PubMed Central

    Morimoto, S. Shizuko; Alexopoulos, George S.

    2011-01-01

    Despite pioneering findings on immune functions in various depressive syndromes, few recent studies focus on the role of inflammation and its potential in generating novel antidepressant therapies. We suggest that geriatric depression is the behavioral syndrome par excellence in which inflammatory processes are likely to play an etiological role. We base this assertion on the following observations: Geriatric depression occurs in the context of medical and neurological illnesses in which inflammatory processes are part of their pathogenesis. Both aging and depression are associated with pronounced and prolonged immune responses. Brain areas related to mood processing, have increased inflammatory responses during aging. Moreover, the connectivity among mood regulating structures may be modulated by inflammatory responses. Geriatric depression exacerbates the pathology of its comorbid medical and neurological disorders raising the question whether depression-related inflammatory changes mediate the worsening of their outcomes. Finally, geriatric depression often occurs in persons exposed to chronic stress, a state precipitating geriatric depression and triggering pro-inflammatory responses. The clinical lesson derived from the available information is that depressed older adults should be examined for inflammatory disorders or risk factors of inflammation. It is premature to use anti-inflammatory agents in the treatment of geriatric depression. However, treatment of co-morbid conditions increasing CNS inflammatory responses can have general health benefits and should be part of clinical practice. Neuroimaging may identify microstructural abnormalities and dysfunction of neural networks associated with inflammatory processes accompanying geriatric depression. Transgenic animal models may help to identify candidate anti-inflammatory agents that later may be tested in clinical trials of geriatric depression. PMID:21536167

  4. Does Anxiety Cause Freezing of Gait in Parkinson's Disease?

    PubMed Central

    Ehgoetz Martens, Kaylena A.; Ellard, Colin G.; Almeida, Quincy J.

    2014-01-01

    Individuals with Parkinson's disease (PD) commonly experience freezing of gait under time constraints, in narrow spaces, and in the dark. One commonality between these different situations is that they may all provoke anxiety, yet anxiety has never been directly examined as a cause of FOG. In this study, virtual reality was used to induce anxiety and evaluate whether it directly causes FOG. Fourteen patients with PD and freezing of gait (Freezers) and 17 PD without freezing of gait (Non-Freezers) were instructed to walk in two virtual environments: (i) across a plank that was located on the ground (LOW), (ii) across a plank above a deep pit (HIGH). Multiple synchronized motion capture cameras updated participants' movement through the virtual environment in real-time, while their gait was recorded. Anxiety levels were evaluated after each trial using self-assessment manikins. Freezers performed the experiment on two separate occasions (in their ON and OFF state). Freezers reported higher levels of anxiety compared to Non-Freezers (p<0.001) and all patients reported greater levels of anxiety when walking across the HIGH plank compared to the LOW (p<0.001). Freezers experienced significantly more freezing of gait episodes (p?=?0.013) and spent a significantly greater percentage of each trial frozen (p?=?0.005) when crossing the HIGH plank. This finding was even more pronounced when comparing Freezers in their OFF state. Freezers also had greater step length variability in the HIGH compared to the LOW condition, while the step length variability in Non-Freezers did not change. In conclusion, this was the first study to directly compare freezing of gait in anxious and non-anxious situations. These results present strong evidence that anxiety is an important mechanism underlying freezing of gait and supports the notion that the limbic system may have a profound contribution to freezing in PD. PMID:25250691

  5. Depressed and nondepressed content self-reference in mild depressives.

    PubMed

    Kuiper, N A; Derry, P A

    1982-03-01

    The present research investigated the extent to which mild depressives and normals differed in their self-referent processing of personal information. In Experiment 1, these subjects made two types of ratings on depressed (e.g., bleak, dismal) and nondepressed (e.g., loyal, organized) content personal adjectives. Half of the adjectives in each content category were rated for a semantic attribute (Does this word have a specific meaning or relate to a specific situation?), whereas half were rated for degree of self-reference (Does this word describe you?). These ratings were followed immediately by an incidental recall task, in which subjects recalled as many of the adjectives as possible. Consistent with predictions generated from a content-specific self-schema model, normals displayed superior recall for self-referenced nondepressed content adjectives, when compared to recall for self-referenced depressed content adjectives and recall for semantic ratings (both depressed and nondepressed content). In contrast, mild depressives exhibited enhanced self-referent recall for both types of content, when compared to their recall for semantic adjectives. This finding suggested that mild depressives utilize a self-schema which incorporates both depressed and nondepressed content. Experiment 2 explored this suggestion further by substituting an other-referent rating task (Does this word describe Pierre Trudeau?) for the semantic judgment used in Experiment 1. Again, consistent with a content-specific self-schema model, normals displayed superior recall only for self-referenced nondepressed adjectives. Mild depressives, however, showed enhanced self-referent recall, relative to other-referent recall, only for depressed content adjectives. For nondepressed content, mild depressives did not distinguish between the self- and other-referent conditions. This finding hinted that the nondepressed component of the mild depressive's self-schema may operate at a somewhat reduced effectiveness, but only when required to differentiate between self and others. PMID:7086630

  6. Scaling characteristics of topographic depressions

    NASA Astrophysics Data System (ADS)

    Le, P. V.; Kumar, P.

    2013-12-01

    Topographic depressions, areas of no lateral surface flow, are ubiquitous characteristic of land surface that control many ecosystem and biogeochemical processes. Landscapes with high density of depressions increase the surface storage capacity, whereas lower depression density increase runoff, thus influencing soil moisture states, hydrologic connectivity and the climate--soil--vegetation interactions. With the widespread availability of high resolution LiDAR based digital elevation model (lDEM) data, it is now possible to identify and characterize the structure of the spatial distribution of topographic depressions for incorporation in ecohydrologic and biogeochemical studies. Here we use lDEM data to document the prevalence and patterns of topographic depressions across five different landscapes in the United States and quantitatively characterize the distribution of attributes, such as surface area, storage volume, and the distance to the nearest neighbor. Through the use of a depression identification algorithm, we show that these distribution attributes follow scaling laws indicative of a fractal structure in which a large fraction of land surface areas can consist of high number of topographic depressions, accounting for 4 to 200 mm of depression storage. This implies that the impacts of small-scale topographic depressions in the fractal landscapes on the redistribution of surface energy fluxes, evaporation, and hydrologic connectivity are quite significant.

  7. The molecular neurobiology of depression

    PubMed Central

    Krishnan, Vaishnav; Nestler, Eric J.

    2009-01-01

    Unravelling the pathophysiology of depression is a unique challenge. Not only are depressive syndromes heterogeneous and their aetiologies diverse, but symptoms such as guilt and suicidality are impossible to reproduce in animal models. Nevertheless, other symptoms have been accurately modelled, and these, together with clinical data, are providing insight into the neurobiology of depression. Recent studies combining behavioural, molecular and electrophysiological techniques reveal that certain aspects of depression result from maladaptive stress-induced neuroplastic changes in specific neural circuits. They also show that understanding the mechanisms of resilience to stress offers a crucial new dimension for the development of fundamentally novel antidepressant treatments. PMID:18923511

  8. The role of rumination in depressive disorders and mixed anxiety\\/depressive symptoms

    Microsoft Academic Search

    Susan Nolen-Hoeksema

    2000-01-01

    Several studies have shown that people who engage in ruminative responses to depressive symptoms have higher levels of depressive symptoms over time, after accounting for baseline levels of depressive symptoms. The analyses reported here showed that rumination also predicted depressive disorders, including new onsets of depressive episodes. Rumination predicted chronicity of depressive disorders before accounting for the effects of baseline

  9. Subtypes of postnatal depression? A comparison of women with recurrent and de novo postnatal depression

    Microsoft Academic Search

    Jane Phillips; Louise Sharpe; Stephen Matthey; Margaret Charles

    2010-01-01

    BackgroundIt has been suggested that there may be two groups of women with postnatal depression (PND) — one who have a history of depression and whose depression is etiologically similar to depression experienced at other times of life, and another who develop depression de novo in the postnatal period and whose depression is uniquely ‘postnatal’. The primary aim of this

  10. Temperament and Character in Psychotic Depression Compared with Other Subcategories of Depression and Normal Controls

    PubMed Central

    Goekoop, Jaap G.; De Winter, Remco F. P.

    2011-01-01

    Background. Support has been found for high harm avoidance as general vulnerability trait for depression and decreased self-directedness (SD) as central state-related personality change. Additional personality characteristics could be present in psychotic depression (PD). Increased noradrenergic activation in PD predicts the involvement of reward dependence (RD). Methods. The data during the acute episode and after full remission from the same subjects, that we used before, were reanalyzed. The dependence of the 7 dimensions of the Temperament and Character Inventory version 9 on PD, three other subcategories of depression, and a group of normal controls was tested by MANCOVA. Results. Low RD at both time points, and low Cooperativeness during the acute episode, were found as additional characteristics of PD. Conclusion. The combination of two premorbid temperaments, high HA and low RD, and the development of a state-related reduction of two character functions, SD and CO, may be the precondition for the development of combined depressive and psychotic psychopathology. PMID:22203891

  11. Cyber victimization by peers: Prospective associations with adolescent social anxiety and depressive symptoms.

    PubMed

    Landoll, Ryan R; La Greca, Annette M; Lai, Betty S; Chan, Sherilynn F; Herge, Whitney M

    2015-07-01

    Peer victimization that occurs via electronic media, also termed cybervictimization, is a growing area of concern for adolescents. The current study evaluated the short-term prospective relationship between cybervictimization and adolescents' symptoms of social anxiety and depression over a six-week period. Participants were 839 high-school aged adolescents (14-18 years; 58% female; 73% Hispanic White), who completed measures of traditional peer victimization, cybervictimization, depression, and social anxiety at two time points. Findings supported the distinctiveness of cybervictimization as a unique form of peer victimization. Furthermore, only cybervictimization was associated with increased levels of depressive symptoms over time, and only relational victimization was associated with increased social anxiety over time, after controlling for the comorbidity of social anxiety and depression among youth. Cybervictimization appears to be a unique form of victimization that contributes to adolescents' depressive symptoms and may be important to target in clinical and preventive interventions for adolescent depression. PMID:25938204

  12. Maternal Depression, Children’s Attachment Security, and Representational Development: An Organizational Perspective

    PubMed Central

    Toth, Sheree L.; Cicchetti, Dante; Rogosch, Fred A.; Sturge-Apple, Melissa

    2009-01-01

    Relations among maternal depression, child attachment, and children’s representations of parents and self were examined. Participants included toddlers and their mothers with a history of Major Depressive Disorder (n=63) or no history of mental disorder (n=68). Attachment was assessed at 20 and 36 months and representations of parents and self were assessed at 36 and 48 months. Depressive symptoms were assessed at all three time points. While early occurring maternal depression had a negative impact on children’s negative and positive representations of parents, attachment security mediated the relation between depressive symptoms and negative representations. Attachment security served as an intervening variable between maternal depression and changes in children’s negative representations of self. Implications for prevention are highlighted. PMID:19236401

  13. No association between dietary patterns and depressive symptoms among a community-dwelling population in Japan

    PubMed Central

    2012-01-01

    Background Studies of the associations between diet and depression have primarily focused on single nutrients or foods. Recently, dietary patterns representing a combination of foods have attracted more interest than individual nutrient. The objective of this study was to examine the association between dietary patterns and depressive symptoms among a community-dwelling population in Japan. Methods We examined the association between dietary patterns and the risk of depression among 791 Japanese community-dwelling individuals. Diet was assessed with a validated brief-type self-administered diet history questionnaire (BDHQ). Dietary patterns from 52 predefined food groups [energy-adjusted food (g/d)] were extracted by principal component analysis. The Center for Epidemiologic Studies Depression Scale (CES-D) with a cut-off point of 16 was used to assess the prevalence of depression. Results A total of 97 subjects (12.3%) were classified as having depression. Four dietary patterns were identified: “Healthy”, “Western”, “Bread and confectionery”, and “Alcohol and accompanying” dietary patterns. After adjusting for potential confounders, the dietary patterns were not related to the risk of depression. Conclusions The present study failed to find associations between dietary patterns and the risk of depression. However, the interpretation of our results was hampered by the lack of certain data, including employment physical activity and longitudinal observations. Potential associations between dietary patterns and depressive symptoms were not completely ruled out. Future research exploring dietary patterns and depressive symptoms is warranted. PMID:23006931

  14. Anger Attacks in Depression – Evidence for a Male Depressive Syndrome

    Microsoft Academic Search

    Dietmar Winkler; Edda Pjrek; Siegfried Kasper

    2005-01-01

    Background: It has been proposed that aggression and especially anger attacks play an important role in the symptomatology of depression. Furthermore, it has been hypothesized that these symptoms are more prevalent in males than in females. Methods: We conducted a study in 217 depressed patients (104 females, 113 males) without psychiatric comorbidity using questionnaires. Study subjects had previously been treated

  15. Gender Differences in Rating Stressful Events, Depression, and Depressive Cognition.

    ERIC Educational Resources Information Center

    Sowa, Claudia J.; Lustman, Patrick J.

    1984-01-01

    Administered the Life Stress Questionnaire, the Beck Depression Inventory, and the Automatic Thought Questionnaire to 140 students. Results showed significant sex differences. Men reported more stressful life change, but women rated the impact of stressors more severely and had higher depression. Men exhibited greater distortions in cognitive…

  16. Freezing of sessile water droplets on surfaces with various roughness and wettability

    NASA Astrophysics Data System (ADS)

    Hao, Pengfei; Lv, Cunjing; Zhang, Xiwen

    2014-04-01

    This paper focus on the freezing delay time and the freezing time of sessile droplet on smooth, micro-structured and micro/nano-structured surfaces, and the whole freezing process are comparatively studied. The freezing delay time of the smooth surfaces with roughness smaller than the size of the critical ice nuclei is found to be much longer than superhydrophobic surfaces with hierarchical structures. Experimental data and theoretical analysis show that the surface roughness plays a very crucial role in nucleation. The freezing delay time could not be extended further on rough surface with more superhydrophobic for sessile droplet. In addition, decreased roughness can increase the free energy barrier for heterogeneous nucleation, result in significant freezing delay. On the contrary, the freezing time from the start of nucleation to the completion of freezing increases with the contact angle. In addition, surfaces with hierarchical roughness are found to have the longest freezing time.

  17. Freeze-In Dark Matter with Displaced Signatures at Colliders

    E-print Network

    Co, Raymond T; Hall, Lawrence J; Pappadopulo, Duccio

    2015-01-01

    Dark matter, $X$, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature $T_R \\ll {\\rm TeV}$. Compared to the conventional radiation-dominated (RD) results, yields from both Freeze-Out and Freeze-In processes are greatly suppressed by dilution from entropy production, making Freeze-Out less plausible while allowing successful Freeze-In with a much larger coupling strength. Freeze-In is typically dominated by the decay of a particle $B$ of the thermal bath, $B \\rightarrow X$. For a large fraction of the relevant cosmological parameter space, the decay rate required to produce the observed dark matter abundance leads to displaced signals at LHC and future colliders, for any $m_X$ in the range ${\\rm keV} < m_X < m_B$ and for values of $m_B$ accessible to these colliders. This result applies whether the early MD era arises after conventional inflation, when $T_R$ is the usual reheat temperature, or is a generic MD era with an alternative origin. I...

  18. Units of freezing of deep supercooled water in woody xylem.

    PubMed

    Hong, S G; Sucoff, E

    1980-07-01

    The low temperature exotherms (LTE) of 1-year-old twigs of Haralson apple (Malus pumila Mill.), shagbark hickory (Carya ovata [Mill.] K. Koch), green ash (Fraxinus pennsylvanica Marsh), honey locust (Gleditsia triacanthos L.), American chestnut (Castanea dentata [Marsh] Borkh.), and red oak (Quercus rubra L.) were determined by differential thermal analysis (DTA). In one type of experiment freezing during a DTA experiment was halted for up to 2.5 hours after part of the supercooled water had frozen at temperatures between -25 and -42 C. Upon resumption of cooling the freezing started within 2 C of the stopping temperature. In a second type of experiment living and dead cells were microscopically observed in the same ray after partial freezing in the DTA apparatus. In another experiment, the LTE persisted even after tangential and radial sectioning of the twig to 0.13 millimeters. In a final experiment the LTE of a single multiseriate ray of red oak had the same shape as the LTE of wood with many uniseriate rays.These experiments confirm that the deep supercooled water in woody xylem or pith freezes in numerous independent events over a span of as much as 20 C. The units which freeze in an event are single cells or small groups of cells. Ice grows very slowly if at all from these units, and water moves very slowly from unfrozen cells to frozen ones. Deep supercooling of ray parenchyma does not require an intact ray. PMID:16661390

  19. Epidemiological Perspectives on Maternal Depression and the Young Child.

    ERIC Educational Resources Information Center

    Garrison, William T.; Earls, Felton J.

    1986-01-01

    Reviews epidemiological studies on the prevalence of maternal depression in the general population and the social etiology of behavioral and psychiatric disorders in early childhood. Also reports an original study conducted in Martha's Vineyard and points out avenues for much-needed further research in this area. (BB)

  20. Help-Seeking Behaviors among Chinese Americans with Depressive Symptoms

    ERIC Educational Resources Information Center

    Leung, Patrick; Cheung, Monit; Tsui, Venus

    2012-01-01

    An exploratory survey indicated that the depression prevalence among Chinese Americans is 17.4 percent. Of 516 respondents, 34.9 percent preferred seeking advice from friends or relatives, followed by 30.2 percent not showing any preference when facing a mental health problem. Logistic regression results pointed to three contributing factors:…

  1. Academic Performance, Popularity, and Depression Predict Adolescent Substance Use.

    ERIC Educational Resources Information Center

    Diego, Miguel A.; Field, Tiffany M.; Sanders, Christopher E.

    2003-01-01

    Eighty-nine high school seniors completed a questionnaire on their feelings and activities, including their use of drugs. Adolescents with a low grade point average, high popularity, and high depression were more likely to smoke cigarettes, drink alcohol, and smoke marijuana than were their peers. Cigarette and alcohol use predicted marijuana use,…

  2. Preparation of chitosan nanocompositeswith a macroporous structure by unidirectional freezing and subsequent freeze-drying.

    PubMed

    Aranaz, Inmaculada; Gutiérrez, María C; Ferrer, María Luisa; del Monte, Francisco

    2014-11-01

    Chitosan is the N-deacetylated derivative of chitin, a naturally abundant mucopolysaccharide that consists of 2-acetamido-2-deoxy-?-d-glucose through a ? (1?4) linkage and is found in nature as the supporting material of crustaceans, insects, etc. Chitosan has been strongly recommended as a suitable functional material because of its excellent biocompatibility, biodegradability, non-toxicity, and adsorption properties. Boosting all these excellent properties to obtain unprecedented performances requires the core competences of materials chemists to design and develop novel processing strategies that ultimately allow tailoring the structure and/or the composition of the resulting chitosan-based materials. For instance, the preparation of macroporous materials is challenging in catalysis, biocatalysis and biomedicine, because the resulting materials will offer a desirable combination of high internal reactive surface area and straightforward molecular transport through broad "highways" leading to such a surface. Moreover, chitosan-based composites made of two or more distinct components will produce structural or functional properties not present in materials composed of one single component. Our group has been working lately on cryogenic processes based on the unidirectional freezing of water slurries and/or hydrogels, the subsequent freeze-drying of which produce macroporous materials with a well-patterned structure. We have applied this process to different gels and colloidal suspensions of inorganic, organic, and hybrid materials. In this review, we will describe the application of the process to chitosan solutions and gels typically containing a second component (e.g., metal and ceramic nanoparticles, or carbon nanotubes) for the formation of chitosan nanocomposites with a macroporous structure. We will also discuss the role played by this tailored composition and structure in the ultimate performance of these materials. PMID:25421320

  3. Clinical Depression and Daily Activity Level

    E-print Network

    McCurdy, Danyale Patrice

    2008-04-28

    Depression has been linked to a number of health problems, including cardiovascular disease (CVD). One link may be depression-related decreases in physical activity. This study was designed to examine physical activity in clinically depressed...

  4. How Do Fundamental Christians Deal with Depression?

    ERIC Educational Resources Information Center

    Spinney, Douglas Harvey

    1991-01-01

    Provides explanation of developmental dynamics in experience of fundamental Christians that provoke reactive depression. Describes depressant retardant defenses against depression that have been observed in Christian fundamental subculture. Suggests four counseling strategies for helping fundamentalists. (Author/ABL)

  5. Conserved and narrow temperature limits in alpine insects: Thermal tolerance and supercooling points of the ice-crawlers, Grylloblatta (Insecta: Grylloblattodea: Grylloblattidae).

    PubMed

    Schoville, Sean D; Slatyer, Rachel A; Bergdahl, James C; Valdez, Glenda A

    2015-07-01

    For many terrestrial species, habitat associations and range size are dependent on physiological limits, which in turn may influence large-scale patterns of species diversity. The temperature range experienced by individuals is considered to shape the breadth of the thermal niche, with species occupying temporally and/or geographically stable climates tolerating a narrow temperature range. High-elevation environments experience large temperature fluctuations, with frequent periods below 0°C, but Grylloblatta (Grylloblattodea: Grylloblattidae) occupy climatically stable microhabitats within this region. Here we test critical thermal limits and supercooling points for five Grylloblatta populations from across a large geographic area, to examine whether the stable microhabitats of this group are associated with a narrow thermal niche and assess their capacity to tolerate cold conditions. Thermal limits are highly conserved in Grylloblatta, despite substantial genetic divergence among populations spanning 1500m elevation and being separated by over 500km. Further, Grylloblatta show exceptionally narrow thermal limits compared to other insect taxa with little capacity to improve cold tolerance via plasticity. In contrast, upper thermal limits were significantly depressed by cold acclimation. Grylloblatta maintain coordinated movement until they freeze, and they die upon freezing. Convergence of the critical thermal minima, supercooling point and lower lethal limits point to adaptation to a cold but, importantly, constant thermal environment. These physiological data provide an explanation for the high endemism and patchy distribution of Grylloblatta, which relies on subterranean retreats to accommodate narrow thermal limits. These retreats are currently buffered from temperature fluctuations by snow cover, and a declining snowpack thus places Grylloblatta at risk of exposure to temperatures beyond its tolerance capacity. PMID:25956197

  6. Measurement of depression and anxiety for hospitalized depressed patients.

    PubMed

    Fischer, E H; Goethe, J W

    1997-05-01

    Standard scales for measuring anxiety and depression did not distinguish between these two psychological constructs in a sample of 295 inpatients with major depressive disorder. Items from these scales were used to form new measures, based on the results of a factor analysis. The new depression and anxiety subscales were internally consistent and only moderately correlated with one another, compared with the standard measures, which were highly correlated. When the factorial procedure was repeated with a subsample of patients with only mild to moderate symptoms, there was no discrimination between depression and anxiety. This finding suggests that when measured in a sample with a restricted range of symptom severity, anxiety and depression have poor discriminant validity. PMID:9144828

  7. Shaft Excavation in Frozen Ground at Point 5

    E-print Network

    Osborne, J

    2000-01-01

    Construction work on the 112 MCHF civil engineering contract started at Point 5 in August 1998. The new surface buildings and underground structures are necessary to accommodate the CMS detector for the LHC Project. The principal underground works consist of two new shafts, two parallel caverns separated by a supporting pillar, and a number of small connection tunnels and service galleries. The two shafts are to be sunk through approximately 50 m of water-bearing moraine to the underlying molasse rock. From a number of possible construction methods, ground freezing of the moraine was considered to be most appropriate. The ground freezing is used to control the groundwater and to support temporarily the moraine during excavation and lining of the shafts. The aim of this paper is to present the ground-freezing technique and to discuss the advantages and disadvantages of the system in the light of its first few months of running on the Point 5 site.

  8. Magnetic seizure therapy improves mood in refractory major depression.

    PubMed

    Kosel, Markus; Frick, Caroline; Lisanby, Sarah H; Fisch, Hans-Ulrich; Schlaepfer, Thomas E

    2003-11-01

    This report describes the successful treatment of a patient suffering from an episode of drug-resistant major depression using magnetic seizure therapy (MST). The patient suffered from recurrent major depression since adolescence. MST is a novel brain stimulation method using transcranial magnetic stimulation at convulsive parameters in order to induce therapeutic seizures under general anesthesia in the same setting used for electroconvulsive therapy (ECT). The first use of therapeutic magnetic seizure induction in a psychiatric patient took place at the University Hospital in Bern, Switzerland, in May 2000. Results of a recent randomized, within-subject, double-masked trial comparing ECT and MST in 10 patients indicate that MST appears to have less subjective and objective side effects, is associated with faster recovery of orientation, and is superior to ECT on measures of attention, retrograde amnesia, and category fluency. ECT has an unparalleled and well-documented efficacy in severe depression but is associated with cognitive side effects. MST is currently under study in several centers with respect to its antidepressant efficacy. We report here on the treatment of a patient with refractory major depression (DSM IV-R), who underwent a series of 12 sessions of MST in an inpatient setting. Baseline Hamilton Depression Rating Scale (HRSD-21) of 33 and Beck Depression Inventory (BDI) of 40 decreased to 6 and 11 respectively, 1 week after completion of the MST trial. Measures of cognitive functions support the hypothesis that MST is associated with a less severe profile of cognitive side effects. [(99m)Tc]-HMPAO SPECT studies (baseline and 4 days after the completion of the MST trial) point to a raise of blood flow at baseline in the left fronto-parietal region and the brainstem. Our preliminary data support the prospect of antidepressant efficacy of MST and point to a benign cognitive side-effect profile in a patient suffering from severe treatment-resistant major depression. PMID:12942146

  9. Depression in university students: Duration, relation to calendar time, prevalence, and demographic correlates

    Microsoft Academic Search

    J. M. Oliver; Robert Burkham

    1979-01-01

    The duration, relation to calendar time, prevalence, and demographic correlates of depression in university students were studied by administering the Beck Depression Inventory to 4 independent samples (N?=?222) either once or twice at 3 points in time separated by 3-wk intervals. The 3-wk test–retest reliability was .78. There was no significant effect of the 3 points in time sampled. 17%

  10. Sleep and Quality of Life in Depression

    Microsoft Academic Search

    Okan Caliyurt

    Major depression is a common disorder; nearly 10% of the population suffers from a depressive illness in any given year. There\\u000a is a strong association between sleep disturbances and depression. The most common sleep disturbance associated with major\\u000a depressive disorder is insomnia. The relationship between insomnia and depression is bidirectional in that insomnia is one\\u000a of the symptoms of depression

  11. Passive ice freezing-releasing heat pipe

    DOEpatents

    Gorski, Anthony J. (Lemont, IL); Schertz, William W. (Batavia, IL)

    1982-01-01

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  12. The cellular neurobiology of depression

    Microsoft Academic Search

    Wayne C. Drevets; Dennis S. Charney; Husseini K. Manji

    2001-01-01

    Major depressive disorders, long considered to be of neurochemical origin, have recently been associated with impairments in signaling pathways that regulate neuroplasticity and cell survival. Agents designed to directly target molecules in these pathways may hold promise as new therapeutics for depression.

  13. Functional impairment in depressed inpatients

    Microsoft Academic Search

    John W. Goethe; Edward H. Fischer

    1995-01-01

    The Sickness Impact Profile (SIP) was administered to 95 patients with major depression. The SIP includes 12 subscales, each representing a specific area of sickness-related dysfunction. To relate these measures to psychiatric symptoms, patients also completed a measure of depression severity. Consistent with earlier findings, there were high levels of functional impairment. Impairment was correlated with symptoms but, as noted

  14. Assessing Interpersonal Subtypes in Depression.

    PubMed

    Simon, Sarah; Cain, Nicole M; Wallner Samstag, Lisa; Meehan, Kevin B; Muran, J Christopher

    2015-01-01

    The context-free diagnoses outlined by the Diagnostic and Statistical Manual of Mental Disorders might not provide enough information to represent the heterogeneity observed in depressed patients. Interpersonal factors have been linked to depression in a mutually influencing pathoplastic relationship where certain problems, like submissiveness, are related to symptom chronicity. This study evaluated interpersonal pathoplasticity in a range of depressive presentations. We examined archival data collected from 407 participants who met criteria for major depressive disorder (MDD), dysthymic disorder (DD), or subthreshold depression (sD). Latent profile analysis (LPA) identified 5 interpersonal subtypes (vindictive, intrusive, socially avoidant, exploitable, and cold). Apart from gender, the subtypes did not differ significantly on demographic characteristics, psychiatric comorbidity, or self-report depression severity. Socially avoidant participants were more likely to meet criteria for a clinical depression diagnosis (MDD or DD), whereas vindictive participants were more likely to have sD. Our results indicate that interpersonal problems could account for heterogeneity observed in depression. PMID:25803309

  15. Tinnitus severity, loudness, and depression

    Microsoft Academic Search

    ROBERT L. FOLMER; SUSAN E. GRIEST; MARY B. MEIKLE; WILLIAM H. MARTIN

    1999-01-01

    Answers to questionnaires filled out by 436 patients who visited our tinnitus clinic were analyzed. Patients were asked to report the presence or absence of depression and to rate the loudness and severity of their tinnitus. Responses to questions about tinnitus loudness and severity from 121 patients who reported current depression were compared with responses from 285 patients who reported

  16. The Many Faces of Depression.

    ERIC Educational Resources Information Center

    Bell, Linda

    1999-01-01

    Reflects on emotional demands experienced by teachers working with depressed students. Describes the pain behind students' depression through personal accounts. Shares strategies on how teachers can remain hopeful and focused on students' needs, including making sure personal needs are met, acknowledging when something positive happens, and…

  17. depression and Alzheimer caregiver stress

    Microsoft Academic Search

    MICHAEL IRWIN; MARVIN BROWN; THOMAS PATTERSON; RICHARD HAUGER; ANNE MASCOVICH

    A reduction in immune function has been found in patients with a major depressive disorder and in persons undergoing severe life stress. This study inves- tigated the association between increased sympathetic nervous system activity and reduced natural killer (NK) cytotoxicity in depression and Alzheimer caregiver stress. NK activity and plasma concentrations of epinephrine, norepinephrine, and neuropeptide Y were measured in

  18. Etiology of Depression in Children

    ERIC Educational Resources Information Center

    Watts, Shirley J.; Markham, Ramona A.

    2005-01-01

    Major Depressive Disorder (MDD) is experienced by a significant proportion of youth today, occurring at an earlier age than found in previous generations. Major Depressive Disorder can produce long-lasting detrimental effects on a child's life, which raises the question of etiology. Three areas were examined for evidence identifying specific…

  19. What Caused the Great Depression?

    ERIC Educational Resources Information Center

    Caldwell, Jean; O'Driscoll, Timothy G.

    2007-01-01

    Economists and historians have struggled for almost 80 years to account for the American Great Depression, which began in 1929 and lasted until the early years of World War II. In this article, the authors discuss three major schools of thought on the causes of the Great Depression and the long failure of the American economy to return to full…

  20. Gastric dysmotility in major depression

    Microsoft Academic Search

    Carmen Quick; Anna Kliem; Sandy Berger; Michael Hocke; Manuel Tancer; Georg Juckel; Vikram K. Yeragani; Karl-Jürgen Bär

    2010-01-01

    BackgroundSomatic symptoms of the gastrointestinal tract occur frequently in major depressive disorder (MDD) and might be associated with the known autonomic imbalance in the disease. Hence, we have investigated gastric electrical activity in patients suffering from major depression before and after treatment by means of electrogastrography (EGG) to investigate a putative association with either the disease state and its symptoms

  1. Depressive Dyadic and Triadic Relationships

    ERIC Educational Resources Information Center

    Rubinstein, David; Timmins, Joan F.

    1978-01-01

    This paper describes some of the characteristics of relationship patterns established by partners with one depressed member. Depressive dyadic and triadic relationships are characterized by repetitive and patterned verbal and non-verbal behavior designated "microcycling". Treatment approaches include therapy of the partners' relationship and of…

  2. Screening Tests for Geriatric Depression

    Microsoft Academic Search

    T. L. Brink; Jerome A. Yesavage; Owen Lum; Philip H. Heersema; Michael Adey; Terrence L. Rose

    1982-01-01

    Contends that the diagnosis of depression in aged patients is the responsibility of both psychologists, and non-psychologists, for it is the latter that is most likely to make initial contact with an elder in need of help. Describes problems in the use of psychometric tests to identify geriatric depression. Reviews the advantages and disadvantages and limitations of scales currently employed.

  3. In favour of freezing eggs for non-medical reasons.

    PubMed

    Goold, Imogen; Savulescu, Julian

    2009-01-01

    This article explores the social benefits and moral arguments in favour of women and couples freezing eggs and embryos for social reasons. Social IVF promotes equal participation by women in employment; it offers women more time to choose a partner; it provides better opportunities for the child as it allows couples more time to become financially stable; it may reduce the risk of genetic and chromosomal abnormality; it allows women and couples to have another child if circumstances change; it offers an option to women and children at risk of ovarian failure; it may increase the egg and embryo pool. There are strong arguments based on equal concern and respect for women which require that women have access to this new technology. Freezing eggs also avoids some of the moral objections associated with freezing embryos. PMID:19076941

  4. Freezing of gait: a practical approach to management.

    PubMed

    Nonnekes, Jorik; Snijders, Anke H; Nutt, John G; Deuschl, Günter; Giladi, Nir; Bloem, Bastiaan R

    2015-07-01

    Freezing of gait is a common and disabling symptom in patients with parkinsonism, characterised by sudden and brief episodes of inability to produce effective forward stepping. These episodes typically occur during gait initiation or turning. Treatment is important because freezing of gait is a major risk factor for falls in parkinsonism, and a source of disability to patients. Various treatment approaches exist, including pharmacological and surgical options, as well as physiotherapy and occupational therapy, but evidence is inconclusive for many approaches, and clear treatment protocols are not available. To address this gap, we review medical and non-medical treatment strategies for freezing of gait and present a practical algorithm for the management of this disorder, based on a combination of evidence, when available, and clinical experience of the authors. Further research is needed to formally establish the merits of our proposed treatment protocol. PMID:26018593

  5. Deconfinement of strangeness and freeze-out from charge fluctuations

    E-print Network

    Swagato Mukherjee; Mathias Wagner

    2013-07-23

    We use Lattice QCD calculations of fluctuations and correlations of various conserved charges to show that the deconfinement of strangeness takes place in the chiral crossover region of QCD; however, inside the quark-gluon plasma strange quarks remain strongly interacting at least up to temperatures twice the QCD crossover temperature. Further, we discuss how the freeze-out parameters of heavy-ion collisions can be determined in a model-independent way through direct comparisons between experimentally measured higher order cumulants of conserved charges and corresponding Lattice QCD calculations. Utilizing the preliminary data from the STAR and PHENIX experiments we illustrate this method. Although, the Lattice QCD based determinations of the freeze-out parameters utilizing data sets of different experiments and different observables are currently not consistent with each other, it is tantalizing to see that all the observed freeze-out parameters lie very close to the chiral/deconfinement crossover region of QCD.

  6. Capture of spatially homogeneous chemical reactions in tissue by freezing.

    PubMed Central

    Clark, A; Clark, P A

    1983-01-01

    A useful technique in studying the saturation of hemoglobin in erythrocytes or myoglobin in tissue is cryophotometry, in which tissue is frozen for later spectrophotometric analysis. A general question associated with this technique is whether the freezing process alters the chemical state. This paper presents a theoretical analysis of the simplest model relevant to that question. We study the effect of rapid cooling on a spatially homogeneous chemical reaction. The analysis shows that changes during freezing are negligible near the boundary to which the heat sink is applied, but can be significant deeper in the sample. The distance from the boundary at which the changes during freezing become appreciable can be expressed simply in terms of the chemical reaction rates and the thermal diffusivity of the tissue. Detailed results are given for the case of oxygen and myoglobin in skeletal muscle. PMID:6838980

  7. Radiobrightness decision criteria for freeze/thaw boundaries

    NASA Technical Reports Server (NTRS)

    Zuerndorfer, B.; England, Anthony W.

    1992-01-01

    A freeze indicator (FI), based on a low 37-GHz radiobrightness and a low 10.7, 18, and 37-GHz radiobrightness spectral gradient, has been used to classify frozen surfaces in the northern Great Plains. By modeling the radiometer beampatterns as Gaussian, freeze/thaw boundaries can be located at the (fine) resolution of the 37-GHz channel. The performance of the freeze indicator, and subsequent boundary location estimate, depends on the accuracy of the boundary decision criteria. It is shown that decision criteria based on clustering and unsupervised classification yield good performance. A simple algorithm for registering coarse-resolution FI boundaries to equivalent boundaries in fine-resolution 37-GHz radiobrightness images is also presented.

  8. The development of a freezing rain sensor for automated surface observing systems

    NASA Astrophysics Data System (ADS)

    Starr, Kevin M.; van Cauwenberghe, Roger

    A freezing precipitations sensor and reporting algorithms have been developed that accurately indicate ice accumulation on aircraft. The sensor and algorithms are briefly described and test results in freezing rain and freezing drizzle, wet snow, and dense fog are discussed. The sensor provides consistent and sensitive indications of ice accumulation under these conditions. Some detection insensitivity occurs when the temperature is at or above freezing or when the ice accumulation is trace. The algorithms are successful in reporting the indications of ice accumulation as either freezing rain or wet snow. Sensor precision is mostly very good and deicing time is negligble except when the temperature is very close to freezing.

  9. Depressed College Students and Tricyclic Antidepressant Therapy.

    ERIC Educational Resources Information Center

    Brown, Ben Maurice

    1978-01-01

    Depressed college students representing several distinct diagnostic groups were studied. Evidence indicates that patients with depressive neurosis show optimal treatment outcomes following tricyclic antidepressant therapy. (JMF)

  10. Screening for depressive symptoms in older adults in the Family Health Strategy, Porto Alegre, Brazil

    PubMed Central

    Nogueira, Eduardo Lopes; Rubin, Leonardo Librelotto; Giacobbo, Sara de Souza; Gomes, Irenio; Cataldo, Alfredo

    2014-01-01

    OBJECTIVE To analyze the prevalence of depression in older adults and associated factors. METHODS Cross-sectional study using a stratified random sample of 621 individuals aged ? 60 from 27 family health teams in Porto Alegre, RS, Southern Brazil, between 2010 and 2012. Community health agents measured depression using the 15-item Geriatric Depression Scale. Scores of ? 6 were considered as depression and between 11 and 15 as severe depression. Poisson regression was used to search for independent associations of sociodemographic and self-perceived health with both depression and its severity. RESULTS The prevalence of depression was 30.6% and was significantly higher in women (35.9% women versus 20.9% men, p < 0.001). The variables independently associated with depression were: female gender (PR = 1.4, 95%CI 1.1;1.8); low education, especially illiteracy (PR = 1.8, 95%CI 1.2;2 6); regular self-rated health (OR = 2.2, 95%CI 1.6;3.0); and poor/very poor self-rated health (PR = 4.0, 95%CI 2.9;5.5). Except for education, the strength of association of these factors increases significantly in severe depression. CONCLUSIONS A high prevalence of depression was observed in the evaluations conducted by community health agents, professionals who are not highly specialized. The findings identified using the 15-item Geriatric Depression Scale in this way are similar to those in the literature, with depression more associated with low education, female gender and worse self-rated health. From a primary health care strategic point of view, the findings become still more relevant, indicating that community health agents could play an important role in identifying depression in older adults. PMID:25119932

  11. Early Intervention to Preempt Major Depression in Older Black and White Adults

    PubMed Central

    Reynolds, Charles F.; Thomas, Stephen B.; Morse, Jennifer Q.; Anderson, Stewart J.; Albert, Steven; Dew, Mary Amanda; Begley, Amy; Karp, Jordan F.; Gildengers, Ariel; Butters, Meryl A.; Stack, Jacqueline A.; Kasckow, John; Miller, Mark D.; Quinn, Sandra C.

    2014-01-01

    Objective Our objective was to assess the efficacy of Problem Solving Therapy for Primary Care (PST-PC) for preventing episodes of major depression and mitigating depressive symptoms in older black and white adults, as compared with an active control condition-- coaching in healthy dietary practices (“DIET”), Methods 247 participants (90 blacks, 154 whites, 3 Asians) with subsyndromal depressive symptoms were recruited into a randomized, “indicated” depression prevention trial comparing effects of PST-PC and DIET on time to episodes of major depressive disorder (SCID/DSM-IV) and level of depressive symptoms (Beck Depression Inventory) over two years. Cumulative intervention time was similar in PST-PC or DIET, averaging 5.5- 6.0 hours in each arm. Results PST-PC and DIET did not differ significantly in time to major depressive episodes (HR = .87; p > .748). Participants in both arms experienced low incidence of such episodes (blacks: n=8, 9%; whites n=13, 8%), compared to published rates of one in four or five over one year in persons with subsyndromal symptoms receiving care as usual. Participants also showed a mean decrease of 4 points in depressive symptoms, sustained over two years. Despite greater burden of depression risk factors among blacks, no significant differences with whites were found in the primary outcome Conclusion Both PST-PC and DIET are potentially effective in protecting older black and white adults with subsyndromal depressive symptoms from developing episodes of major depression over two years. Absent a control for concurrent usual care, this conclusion is preliminary. If confirmed, both interventions hold promise as scalable, safe, non-stigmatizing interventions for delaying or preventing episodes of major depression in the nation’s increasingly diverse older population. PMID:24632760

  12. Effect of freezing on Fossomatic cell counting in ewe milk.

    PubMed

    Martínez, J R; Gonzalo, C; Carriedo, J A; San Primitivo, F

    2003-08-01

    Using the Fossomatic method, a total of 10,072 analytical somatic cell count (SCC) observations were carried out on 4760 aliquots taken from 70 individual ewe milk samples with the objective of studying whether freezing showed significant differences of SCC in comparison with refrigeration, according to different analytical conditions. These conditions were four preservation procedures (without preservation, potassium dichromate, azidiol, and bronopol), two storage temperatures (refrigeration and freezing), five milk ages within storage (24 h postcollection in refrigeration, and 24 h, 15, 30, and 60 d postcollection in freezing), two thawing types (rapid and slow), and two analytical temperatures (40 and 60 degrees C). Preservation, storage, and analytical temperature, type of thawing and milk age within storage, and most of the interactions showed a significant effect on the SCC variation. On average, the SCC was lower after freezing than in refrigeration. This effect depended specifically on type of preservation and analytical temperature of milk. The SCC of milk unpreserved or preserved with bronopol or potassium dichromate, and analyzed at 40 degrees C, was not affected by freezing; however, use of azidiol as a preservative before freezing, and heating the milk to 60 degrees C following thawing resulted in significantly decreased SCC. Milk age had little quantitative influence on SCC of thawed milk. The type of thawing (rapid and slow) did not significantly influence SCC of milk analyzed at 40 degrees C. As a result, when using properly handled samples, the Fossomatic method could be used to enumerate SCC in samples frozen over the 60 d. PMID:12939082

  13. Ultrasonic emissions from conifer xylem exposed to repeated freezing.

    PubMed

    Mayr, Stefan; Zublasing, Verena

    2010-01-01

    Ultrasonic emission measurements enable the analysis of xylem cavitation induced by drought and freeze-thaw events. Several studies have indicated that ultrasonic acoustic emissions (UAE) in conifers occur upon freezing and not upon thawing, although classical theory has postulated gas bubble formation during freezing and cavitation during thawing. We analyzed the pattern and quality of freeze-thaw-induced UAE in seven conifers (Abies alba, Larix decidua, Juniperus communis, Picea abies, Pinus cembra, Pinus mugo, Pinus sylvestris). Axes samples dehydrated to different water potentials were exposed to repeated frost cycles. The number, amplitude and energy of UAE signals were registered and related to water potential, temperature course and wood characteristics (wood density, tracheid diameter). For P. abies, ultrasonic emission analysis was also performed on bark samples, xylem samples without bark, as well as on stems of young potted trees. In all conifers, UAE were registered in water-stressed samples but not in saturated or dehydrated samples. No signals were emitted by the bark of P. abies. Ultrasonic activity occurred only upon freezing, and identical patterns were observed in axes samples and stems of potted P. abies trees. A weak positive relationship between tracheid diameter and UAE energy was observed, indicating wide tracheids to emit signals with higher energy. The classical bubble formation hypothesis cannot sufficiently explain the occurrence of UAE during freezing and upon repeated temperature cycles, as demonstrated in this study. We suggest that the low water potential of ice induces air-seeding near the ice-water interface, and consequently, causes UAE. PMID:19692146

  14. DEP: A Depression Emulation Program*

    PubMed Central

    Webster, Charles; Glass, Richard M; Banks, Gordon

    1988-01-01

    Cognitive deficits can be studied by “lesioning” computer simulations of normal cognitive processes. DEP (Depression Emulation Program) implements key aspects of a computational theory of “normal” adaptive reactive depression. A theory of “normal” depression is a step toward a theory of “pathological” depression. Transient depressed mood caused by an environmental event may be an example of fallure-triggered reprogramming of the self-schema. We normally generate responses to our environment in a fast and effortless “compiled” mode. After experiencing a stable, internal, and global failure, we debug our self-schema in a slow and effortful “interpreted” mode. During debugging, we experience a cognitive loop, increased objectivity, decreased motivation, and fluctuating self-generalizations. DEP exhibits analogous behavior and suggests vulnerability in an emotional operating system that normally, and periodically, adapts to a changing environment. Computer simulation of cognitive deficit may become a valuable research tool in psychiatry and neurology.

  15. Thermal and Chemical Freeze-out in Spectator Fragmentation

    E-print Network

    W. Trautmann; R. Bassini; M. Begemann-Blaich; A. Ferrero; S. Fritz; S. J. Gaff-Ejakov; C. Gross; G. Imme; I. Iori; U. Kleinevoss

    2007-12-17

    Isotope temperatures from double ratios of hydrogen, helium, lithium, beryllium, and carbon isotopic yields, and excited-state temperatures from yield ratios of particle-unstable resonances in 4He, 5Li, and 8Be, were determined for spectator fragmentation, following collisions of 197Au with targets ranging from C to Au at incident energies of 600 and 1000 MeV per nucleon. A deviation of the isotopic from the excited-state temperatures is observed which coincides with the transition from residue formation to multi-fragment production, suggesting a chemical freeze-out prior to thermal freeze-out in bulk disintegrations.

  16. Freeze-out conditions from fluctuations of conserved charges

    NASA Astrophysics Data System (ADS)

    Ratti, C.; Borsanyi, S.; Fodor, Z.; Katz, S. D.; Krieg, S.; Szabo, K. K.

    2014-11-01

    The latest results on fluctuations of electric charge and baryon number, simulated on the lattice by the Wuppertal-Budapest Collaboration, are compared to the moments of multiplicity distribution of the corresponding conserved charges, measured in heavy ion collision experiments by the STAR Collaboration. The purpose of this study is to extract the chemical freeze-out parameters (temperature and chemical potential) as a function of the collision energy, from first principles. Consistency between the freeze-out parameters obtained through the two different conserved charges used in the analysis is discussed.

  17. Thermal and chemical freeze-out in spectator fragmentation

    NASA Astrophysics Data System (ADS)

    Trautmann, W.; Bassini, R.; Begemann-Blaich, M.; Ferrero, A.; Fritz, S.; Gaff-Ejakov, S. J.; Groß, C.; Immé, G.; Iori, I.; Kleinevoß, U.; Kunde, G. J.; Kunze, W. D.; Fèvre, A. Le; Lindenstruth, V.; ?ukasik, J.; Lynen, U.; Maddalena, V.; Mahi, M.; Möhlenkamp, T.; Moroni, A.; Müller, W. F. J.; Nociforo, C.; Ocker, B.; Odeh, T.; Orth, H.; Petruzzelli, F.; Pochodzalla, J.; Raciti, G.; Riccobene, G.; Romano, F. P.; Rubehn, Th.; Saija, A.; Sann, H.; Schnittker, M.; Schüttauf, A.; Schwarz, C.; Seidel, W.; Serfling, V.; Sfienti, C.; Trzci?ski, A.; Tucholski, A.; Verde, G.; Wörner, A.; Xi, Hongfei; Zwiegli?ski, B.

    2007-12-01

    Isotope temperatures from double ratios of hydrogen, helium, lithium, beryllium, and carbon isotopic yields, and excited-state temperatures from yield ratios of particle-unstable resonances in He4, Li5, and Be8, were determined for spectator fragmentation, following collisions of Au197 with targets ranging from C to Au at incident energies of 600 and 1000 MeV per nucleon. A deviation of the isotopic from the excited-state temperatures is observed which coincides with the transition from residue formation to multi-fragment production, suggesting a chemical freeze-out prior to thermal freeze-out in bulk disintegrations.

  18. Thermal and chemical freeze-out in spectator fragmentation

    SciTech Connect

    Trautmann, W.; Begemann-Blaich, M.; Fritz, S.; Gross, C.; Kleinevoss, U.; Kunze, W. D.; Le Fevre, A.; Lynen, U.; Mahi, M.; Mueller, W. F. J.; Odeh, T.; Orth, H.; Rubehn, Th.; Sann, H.; Schnittker, M.; Schwarz, C.; Sfienti, C.; Woerner, A.; Xi Hongfei [Gesellschaft fuer Schwerionenforschung mbH, D-64291 Darmstadt (Germany); Bassini, R. [Istituto di Scienze Fisiche, Universita degli Studi di Milano and I. N. F. N., I-20133 Milano (Italy)] (and others)

    2007-12-15

    Isotope temperatures from double ratios of hydrogen, helium, lithium, beryllium, and carbon isotopic yields, and excited-state temperatures from yield ratios of particle-unstable resonances in {sup 4}He, {sup 5}Li, and {sup 8}Be, were determined for spectator fragmentation, following collisions of {sup 197}Au with targets ranging from C to Au at incident energies of 600 and 1000 MeV per nucleon. A deviation of the isotopic from the excited-state temperatures is observed which coincides with the transition from residue formation to multi-fragment production, suggesting a chemical freeze-out prior to thermal freeze-out in bulk disintegrations.

  19. Surface Nucleation in the Freezing of Gold Nanoparticles

    E-print Network

    Eduardo Mendez-Villuendas Richard K. Bowles

    2007-04-03

    We use molecular simulation to calculate the nucleation free energy barrier for the freezing of a 456 atom gold cluster over a range of temperatures. The results show that the embryo of the solid cluster grows at the vapor-surface interface for all temperatures studied and that the usual classical nucleation model, with the embryo growing in the core of the cluster, is unable to predict the shape of the free energy barrier. We use a simple partial wetting model that treats the crystal as a lens shaped nucleus at the liquid-vapor interface and find that the line tension plays an important role in the freezing of gold nanoparticles.

  20. Freezing of Spinodal Decompostion by Irreversible Chemical Growth Reaction

    E-print Network

    Michael Schulz; Benjamin Paul

    1998-08-10

    We present a description of the freezing of spinodal decomposition in systems, which contain simultaneous irreversible chemical reactions, in the hydrodynamic limit approximation. From own results we conclude, that the chemical reaction leads to an onset of spinodal decomposition also in the case of an initial system which is completely miscible and can lead to an extreme retardation of the dynamics of the spinodal decomposition, with the probability of a general freezing of this process, which can be experimetally observed in simultaneous IPN formation.