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1

The Freezing Point Depression Law in Physical Chemistry.  

ERIC Educational Resources Information Center

Suggests a change in physical chemistry courses to use a slightly more complicated but significantly more useful generalization of the simple freezing point depression law. Lists reasons for the change and presents the treatment of solid-liquid equilibria where solid-solution is allowed. Provides a mathematical treatment. (MVL)

Franzen, Hugo F.

1988-01-01

2

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

SciTech Connect

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.

Hayashi, K.; Kasza, K.

2000-05-03

3

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

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

4

Effects of Dissolved Oxygen and Freezing Techniques on the Silver Freezing Point  

Microsoft Academic Search

The freezing point of silver is being considered as a joining point between platinum resistance thermometry and optical pyrometry. Therefore the freezing points of high purity samples of silver have been investigated. An important impurity effect arises from the depression of the freezing point of pure Ag caused by residual dissolved oxygen contents in some samples. Melting range parameters were

G. Bongiovanni; L. Crovini; P. Marcarino

1975-01-01

5

Solutions : FreezePtDepression (20 Variations)  

NSDL National Science Digital Library

It takes 6.86 kg of ethylene glycol (antifreeze) to decrease the freezing point of 6.50 kg of water to -25.0 o F (-31.7 o C). How much sodium chloride (NaCl) would it take to decrease the freezing point of 6.50 kg of water to -25.0 o F? (Assuming all the salt will dissolve in that amount of water.)

6

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...

7

Plant Moisture Stress: A Portable Freezing-Point Meter Compared with the Psychrometer1  

Microsoft Academic Search

A small portable instrument for measuring the freezing- point depression of plant tissue has been developed for field use. The instrument is easy to operate and can be constructed from materials costing less than $100. Moisture stress measurements made with the Freezing- point meter on a variety of plants were compared with vapor pressure psychrometer measurments. Variation be- tween duplicates

J. W. Cary; H. D. Fisher

1969-01-01

8

Device and method for determining freezing points  

NASA Technical Reports Server (NTRS)

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).

Mathiprakasam, Balakrishnan (Inventor)

1986-01-01

9

Realization of the Copper Freezing Point by Pyrometry.  

National Technical Information Service (NTIS)

The scope of the paper is to describe the apparatus and method of the realization of the copper freezing point using the NIM's photoelectric comparator. The standard deviation of the point was estimated to be 0.02 deg C. The overall uncertainty in this re...

Q. Zhao D. Li Z. Yuan Z. Chang

1987-01-01

10

High-freezing-point fuels used for aviation turbine engines  

NASA Technical Reports Server (NTRS)

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.

Friedman, R.

1979-01-01

11

High freezing point fuels used for aviation turbine engines  

NASA Technical Reports Server (NTRS)

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.

Friedman, R.

1979-01-01

12

Standard Reference Materials: Standard Reference Material 1747: Tin Freezing-Point Cell and Standard Reference Material 1748: Zinc Freezing-Point Cell.  

National Technical Information Service (NTIS)

The freezing points of Sn (231.928 deg C) and Zn (419.527 deg C) are defining fixed points of the International Temperature Scale of 1990 (ITS-90). Realization of these freezing points is performed using fixed-points cells containing high-purity (> or = 9...

G. F. Strouse A. T. Ince

1997-01-01

13

Freezing and Melting  

NSDL National Science Digital Library

This article tells how the freezing point of a substance is also its melting point. The energy of the substance's molecules changes with temperature, thus with changes in state. Also described is how freezing points can be lowered, or depressed, by adding a substance.

2010-01-01

14

Standard Reference Materials: Tin Freezing-Point Standard: SRM 741a.  

National Technical Information Service (NTIS)

The freezing point of tin (231.928 degrees C) is a defining fixed point of the International Temperature Scale of 1990 (ITS-90). Realization of this freezing point is performed using a fixed-point cell containing high-purity (> or = 99.9999% pure) tin. A ...

G. F. Strouse N. P. Moiseeva

1999-01-01

15

A Study of the Realization of the Melting and Freezing Points of Silver  

NASA Astrophysics Data System (ADS)

Freezing and melting behaviour of our silver sample was studied using conventional procedures and also using conditions that were nearly adiabatic in order to obtain an equilibrium melting curve. The results indicate that the freezing point of a silver sample of six-9s purity is reproducible well within one millikelvin, provided that experimental conditions to realize it are reproduced. the melting range from 10% liquid to the liquidus point is about 28 mK, and the freezing point obtained following a supercool can be one to several mK below the liquidus point, depending upon the freezing technique used.

Ancsin, J.

1989-01-01

16

The Siberian timberman Acanthocinus aedilis: a freeze-tolerant beetle with low supercooling points.  

PubMed

Larvae of the Siberian timberman beetle Acanthocinus aedilis display a number of unique features, which may have important implications for the field of cold hardiness in general. Their supercooling points are scattered over a wide temperature range, and some individuals have supercooling points in the low range of other longhorn beetles. However, they differ from other longhorn beetles in being tolerant to freezing, and in the frozen state they tolerate cooling to below -37 degrees C. In this respect they also differ from the European timberman beetles, which have moderate supercooling capacity and die if they freeze. The combination of freezing tolerance and low supercooling points is unusual and shows that freezing at a high subzero temperature is not an absolute requirement for freezing tolerance. Like other longhorn beetles, but in contrast to other freeze-tolerant insects, the larvae of the Siberian timberman have a low cuticular water permeability and can thus stay supercooled for long periods without a great water loss. This suggests that a major function of the extracellular ice nucleators of some freeze-tolerant insects may be to prevent intolerable water loss in insects with high cuticular water permeability, rather than to create a protective extracellular freezing as has generally been assumed. The freezing tolerance of the Siberian timberman larvae is likely to be an adaptation to the extreme winter cold of Siberia. PMID:19153749

Kristiansen, E; Li, N G; Averensky, A I; Laugsand, A E; Zachariassen, K E

2009-07-01

17

Practical limitations of ITS-90 from the mercury triple point to the silver freeze point  

SciTech Connect

The NPL published a forward to the ITS-90 text as follows:- 'The purpose of the ITS is to define procedures by which certain specified practical thermometers of the required quality can be calibrated in such a way that the values of temperature obtained from them can be precise and reproducible, while at the same time closely approximating the corresponding thermodynamic values.' [1]. The paper investigates the properties of thirty four lots of 6N pure metal used to make cells conforming to ITS-90 from mercury through silver over a period of twenty years. Three hundred individual cells are analysed by the impurities listed and supplied with each lot, melt and freeze curve slopes are also summarised for each lot and depressions calculated. These are then compared to the slopes and depressions suggested in the Supplementary Information for the ITS-90 and in CCT/2000-13 'Optimal Realizations'. Results are summarised, tabulated and discussed. Three lots of the thirty four were found to produce cells outside 6N expectations; however the remaining thirty one lots no matter how well or badly the accompanying certification was presented produced cells that conformed to 6N expectations as suggested in Supplementary Information to ITS-90 and CCT/2000-13.

Tavener, J. P.; Tavener, S. J.; Tavener, I. F.; Davies, N. [Isothermal Technology Ltd (Isotech), Pine Grove, Southport, Merseyside, PR9 9AG, England (United Kingdom)] [Isothermal Technology Ltd (Isotech), Pine Grove, Southport, Merseyside, PR9 9AG, England (United Kingdom)

2013-09-11

18

Practical limitations of ITS-90 from the mercury triple point to the silver freeze point  

NASA Astrophysics Data System (ADS)

The NPL published a forward to the ITS-90 text as follows:- "The purpose of the ITS is to define procedures by which certain specified practical thermometers of the required quality can be calibrated in such a way that the values of temperature obtained from them can be precise and reproducible, while at the same time closely approximating the corresponding thermodynamic values." [1]. The paper investigates the properties of thirty four lots of 6N pure metal used to make cells conforming to ITS-90 from mercury through silver over a period of twenty years. Three hundred individual cells are analysed by the impurities listed and supplied with each lot, melt and freeze curve slopes are also summarised for each lot and depressions calculated. These are then compared to the slopes and depressions suggested in the Supplementary Information for the ITS-90 and in CCT/2000-13 "Optimal Realizations". Results are summarised, tabulated and discussed. Three lots of the thirty four were found to produce cells outside 6N expectations; however the remaining thirty one lots no matter how well or badly the accompanying certification was presented produced cells that conformed to 6N expectations as suggested in Supplementary Information to ITS-90 and CCT/2000-13.

Tavener, J. P.; Tavener, S. J.; Tavener, I. F.; Davies, N.

2013-09-01

19

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

NASA Technical Reports Server (NTRS)

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.

Pasion, A. J.

1979-01-01

20

When hot water freezes before cold  

Microsoft Academic Search

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

J. I. Katz

2006-01-01

21

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

22

Standard Reference Material 1745: Indium Freezing-Point Standard and Standard Reference Material 2232: Indium DSC Melting-Point Standard.  

National Technical Information Service (NTIS)

The freezing point of indium (156.5985 degrees C) is a defining fixed-point cell containing high-purity (greater than or equal to 99.999% pure) indium. A single lot of indium (greater than or equal to 99.999% pure) constituting Standard Reference Material...

G. F. Strouse

2001-01-01

23

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

NASA Technical Reports Server (NTRS)

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.

Mathiprakasam, B.

1982-01-01

24

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

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

25

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

PubMed

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

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

2014-04-01

26

Point-prevalence of depression and associated risk factors.  

PubMed

The study aimed to assess levels of depressive symptoms and associated risk factors in a sample of students in Bogotá, Colombia. A convenient sample (N = 254) of students at the University Antonio Nariño, Bogotá was invited to complete an online survey that contained questions associated with common risk factors for depression and the Beck Depression Inventory (BDI-II). Chi-square was used to analyze comparisons between demographic and risk factors and severity of depression, and comparisons between those depressed and not depressed. Odds Ratios and their 95% confidence interval (95% CI) were computed through logistic regression model developed for each independent variable. The point-prevalence of current depressive symptoms was 36.2%; women 47.3% and men 21.3%. Risk factors associated with depression included being a woman, having a previous diagnosis, suicidal ideation and (or) intent, sleep problems, a recent loss, and a history of family depression and alcoholism. The study confirms the high incidence of depression and associated risk factors in students. The results demonstrate a need for prevention measures, early detection and early intervention. PMID:24839729

Richards, Derek; Sanabria, Alicia Salamanca

2014-01-01

27

Measurement of the in freezing-point temperature: Effect of the liquid-solid interface structure  

NASA Astrophysics Data System (ADS)

The results of the experimental study of the inner interface formation process under different conditions of its initiation for the indium freezing point showed that, depending on the initiation intensity, both the planar structure of the interface on the thermometer well and a noticeable intergrowth of dendrites could be obtained. However, under some specific initiation conditions dendrites disappeared partly or completely in the process of crystallization. The value of the indium freezing point temperature was measured under realization conditions corresponding to different inner interface structure.

Ivanova, A. G.; Abasov, M. Yu.; Gerasimov, S. F.; Pokhodun, A. I.

2013-09-01

28

Experimental results for the rapid determination of the freezing point of fuels  

NASA Technical Reports Server (NTRS)

Two methods for the rapid determination of the freezing point of fuels were investigated: an optical method, which detected the change in light transmission from the disappearance of solid particles in the melted fuel; and a differential thermal analysis (DTA) method, which sensed the latent heat of fusion. A laboratory apparatus was fabricated to test the two methods. Cooling was done by thermoelectric modules using an ice-water bath as a heat sink. The DTA method was later modified to eliminate the reference fuel. The data from the sample were digitized and a point of inflection, which corresponds to the ASTM D-2386 freezing point (final melting point), was identified from the derivative. The apparatus was modifified to cool the fuel to -60 C and controls were added for maintaining constant cooling rate, rewarming rate, and hold time at minimum temperature. A parametric series of tests were run for twelve fuels with freezing points from -10 C to -50 C, varying cooling rate, rewarming rate, and hold time. Based on the results, an optimum test procedure was established. The results showed good agreement with ASTM D-2386 freezing point and differential scanning calorimetry results.

Mathiprakasam, B.

1984-01-01

29

Thermodynamic temperature measurements of silver freezing point and HTFPs  

NASA Astrophysics Data System (ADS)

The hybrid method, by introducing a lens to the irradiance method, was adopted to measure the thermodynamic temperature at NIM. An absolute radiation thermometer was established with two alternative filter radiometers (633nm and 900nm). The parameters of the absolute radiation thermometer were calibrated. The thermodynamic temperatures of the silver fixed point and Co-C, Pt-C, Re-C were determined. The uncertainties were 0.24K to 0.94K for FR633 and 0.34K to 1.6K for FR900 from the silver point to Re-C. The results were compared with the ITS-90 values and show a good agreement: 0.18K at Co-C, -0.11K at Pt-C and -0.24K at Re-C, which are under the estimated uncertainties.

Yuan, Z.; Lu, X.; Hao, X.; Dong, W.; Wang, T.; Lin, Y.; Wang, J.; Duan, Y.

2013-09-01

30

Relationship Between Ice Nucleation Temperature Depression and Equilibrium Melting Points Depression of Medaka (Oryzias latipes) Embryos  

NASA Astrophysics Data System (ADS)

We measured the ice nucleation temperature depression , ?Tf , and equilibrium melting points depression, ?Tm, of Medaka (Oryzias latipes) embryos with different cryoprotectant (ethylene glycol, 1.3-propanediol, 1.4-butanediol, glycerol aqueous solutions) treatments. Our obtained results showed the good relationship between the ?Tf ,and ?Tm all samples. In addition the value of ? , which can be obtained from the linear relationship, ?Tf =? ?Tm, were confirmed to show correlation with the value of ? , as obtained by the W/O emulsion method.

Kimizuka, Norihito; Suzuki, Toru

31

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

PubMed Central

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.

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

1969-01-01

32

Universal behavior of repulsive two-dimensional fermions in the vicinity of the quantum freezing point  

NASA Astrophysics Data System (ADS)

We show by a meta-analysis of the available Quantum Monte Carlo (QMC) results that two-dimensional fermions with repulsive interactions exhibit universal behavior in the strongly correlated regime, and that their freezing transition can be described using a quantum generalization of the classical Hansen-Verlet freezing criterion. We calculate the liquid-state energy and the freezing point of the 2D dipolar Fermi gas (2DDFG) using a variational method by taking ground-state wave functions of 2D electron gas (2DEG) as trial states. A comparison with the recent fixed-node diffusion Monte Carlo analysis of the 2DDFG shows that our simple variational technique captures more than 95% of the correlation energy, and predicts the freezing transition within the uncertainty bounds of QMC. Finally, we utilize the ground-state wave functions of 2DDFG as trial states and provide a variational account of the effects of finite 2D confinement width. Our results indicate significant beyond mean-field effects. We calculate the frequency of collective monopole oscillations of the quasi-2D dipolar gas as an experimental demonstration of correlation effects.

Babadi, Mehrtash; Skinner, Brian; Fogler, Michael M.; Demler, Eugene

2013-07-01

33

Bovine serum albumin: survival and osmolarity effect in bovine spermatozoa stored above freezing point.  

PubMed

Liquid nitrogen preservation in remote farms is a limitation. The goal of this study was to determine optimum temperature above freezing point for bovine spermatozoa preservation using bovine serum albumin (BSA) as a supplementation. Pooled semen sample from three ejaculates was subjected to various BSA concentration (1, 4, 8 and 12 mg ml(-1)), before incubation in different above freezing point temperatures (4, 25 and 37 °C). Viability assessment was carried out against time from day 0 (fresh sample) until all spermatozoa become nonviable. Optimal condition for bovine spermatozoa storage was at 4 °C with 1 mg ml(-1) BSA for almost 7 days. BSA improved bovine spermatozoa viability declining rate to 44.28% at day 4 and 57.59% at day 7 compared to control, with 80.54% and 98.57% at day 4 and 7 respectively. Increase in BSA concentration did not improve sperm viability. Our results also confirmed that there was a strong negative correlation between media osmolarity and bovine spermatozoa survival rate with r = 0.885, P < 0.0001. Bovine serum albumin helps to improve survival rate of bovine spermatozoa stored above freezing point. PMID:21806660

Nang, C F; Osman, K; Budin, S B; Ismail, M I; Jaffar, F H F; Mohamad, S F S; Ibrahim, S F

2012-05-01

34

Freezing Ice  

NSDL National Science Digital Library

The purpose of this assessment probe is to elicit students' ideas about freezing point. The probe is designed to find out whether students recognize that water freezes at the same time independent of the volume of water.

Eberle, Francis; Tugel, Joyce; Keeley, Page

2007-01-01

35

Ultra-high temperature isothermal furnace liners (IFLS) for copper freeze point cells  

NASA Astrophysics Data System (ADS)

Primary Laboratories use large fixed-point cells in deep calibration furnaces utilizing heat pipes to achieve temperature uniformity. This combination of furnace, heat pipe, and cell gives the smallest of uncertainties. The heat pipe, also known as an isothermal furnace liner (IFL), has typically been manufactured with Alloy 600/601 as the envelope material since the introduction of high temperature IFLs over 40 years ago. Alloy 600/601 is a widely available high temperature material, which is compatible with Cesium, Potassium, and Sodium and has adequate oxidation resistance and reasonable high temperature strength. Advanced Cooling Technologies, Inc. (ACT) Alloy 600/Sodium IFLs are rated to 1100°C for approximately 1000 hours of operation (based on creep strength). Laboratories interested in performing calibrations and studies around the copper freezing point (1084.62°C) were frustrated by the 1000 hours at 1100°C limitation and the fact that expensive freeze-point cells were getting stuck and/or crushed inside the IFL. Because of this growing frustration/need, ACT developed an Ultra High Temperature IFL to take advantage of the exceptional high temperature strength properties of Haynes 230.

Dussinger, P. M.; Tavener, J. P.

2013-09-01

36

Improvements in the realization of the ITS-90 over the temperature range from the melting point of gallium to the freezing point of silver at NIM  

SciTech Connect

The temperature primary standard over the range from the melting point of gallium to the freezing point of silver in National institute of Metrology (NIM), China, was established in the early 1990s. The performance of all of fixed-point furnaces degraded and needs to be updated due to many years of use. Nowadays, the satisfactory fixed point materials can be available with the development of the modern purification techniques. NIM plans to use a group of three cells for each defining fixed point temperature. In this way the eventual drift of individual cells can be evidenced by periodic intercomparison and this will increase the reliability in disseminating the ITS-90 in China. This article describes the recent improvements in realization of ITS-90 over temperature range from the melting point of gallium to the freezing point of silver at NIM. Taking advantages of the technological advances in the design and manufacture of furnaces, the new three-zone furnaces and the open-type fixed points were developed from the freezing point of indium to the freezing point of silver, and a furnace with the three-zone semiconductor cooling was designed to automatically realize the melting point of gallium. The reproducibility of the new melting point of gallium and the new open-type freezing points of In, Sn, Zn. Al and Ag is improved, especially the freezing points of Al and Ag with the reproducibility of 0.2mK and 0.5mK respectively. The expanded uncertainty in the realization of these defining fixed point temperatures is 0.34mK, 0.44mK, 0.54mK, 0.60mK, 1.30mK and 1.88mK respectively.

Sun, J.; Zhang, J. T.; Ping, Q. [National institute of Metrology, Beijing (China)] [National institute of Metrology, Beijing (China)

2013-09-11

37

Improvements in the realization of the ITS-90 over the temperature range from the melting point of gallium to the freezing point of silver at NIM  

NASA Astrophysics Data System (ADS)

The temperature primary standard over the range from the melting point of gallium to the freezing point of silver in National institute of Metrology (NIM), China, was established in the early 1990s. The performance of all of fixed-point furnaces degraded and needs to be updated due to many years of use. Nowadays, the satisfactory fixed point materials can be available with the development of the modern purification techniques. NIM plans to use a group of three cells for each defining fixed point temperature. In this way the eventual drift of individual cells can be evidenced by periodic intercomparison and this will increase the reliability in disseminating the ITS-90 in China. This article describes the recent improvements in realization of ITS-90 over temperature range from the melting point of gallium to the freezing point of silver at NIM. Taking advantages of the technological advances in the design and manufacture of furnaces, the new three-zone furnaces and the open-type fixed points were developed from the freezing point of indium to the freezing point of silver, and a furnace with the three-zone semiconductor cooling was designed to automatically realize the melting point of gallium. The reproducibility of the new melting point of gallium and the new open-type freezing points of In, Sn, Zn. Al and Ag is improved, especially the freezing points of Al and Ag with the reproducibility of 0.2mK and 0.5mK respectively. The expanded uncertainty in the realization of these defining fixed point temperatures is 0.34mK, 0.44mK, 0.54mK, 0.60mK, 1.30mK and 1.88mK respectively.

Sun, J.; Zhang, J. T.; Ping, Q.

2013-09-01

38

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

ERIC Educational Resources Information Center

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…

Pinarbasi, Tacettin; Sozbilir, Mustafa; Canpolat, Nurtac

2009-01-01

39

Freezing induces a loss of freeze tolerance in an overwintering insect.  

PubMed Central

Cold-hardy insects overwinter by one of two main strategies: freeze tolerance and freeze avoidance by supercooling. As a general model, many freeze-tolerant species overwinter in extreme climates, freeze above -10 degrees C via induction by ice-nucleating agents, and once frozen, can survive at temperatures of up to 40 degrees C or more below the initial freezing temperature or supercooling point (SCP). It has been assumed that the SCP of freeze-tolerant insects is unaffected by the freezing process and that the freeze-tolerant state is therefore retained in winter though successive freeze-thaw cycles of the body tissues and fluids. Studies on the freeze-tolerant larva of the hoverfly Syrphus ribesii reveal this assumption to be untrue. When a sample with a mean 'first freeze' SCP of -7.6 degrees C (range of -5 degrees C to -9.5 degrees C) were cooled, either to -10 degrees C or to their individual SCP, on five occasions, the mean SCP was significantly depressed, with some larvae subsequently freezing as low as -28 degrees C. Only larvae that froze at the same consistently high temperature above -10 degrees C were alive after being frozen five times. The wider occurrence of this phenomenon would require a fundamental reassessment of the dynamics and distinctions of the freeze-tolerant and freeze-avoiding strategies of insect overwintering.

Brown, C. L.; Bale, J. S.; Walters, K. F. A.

2004-01-01

40

TOPICAL REVIEW: Confinement effects on freezing and melting  

Microsoft Academic Search

A review of experimental work on freezing and melting in confinement is presented. A range of systems, from metal oxide gels to porous glasses to novel nanoporous materials, is discussed. Features such as melting-point depression, hysteresis between freezing and melting, modifications to bulk solid structure and solid-solid transitions are reviewed for substances such as helium, organic fluids, water and metals.

Hugo K. Christenson

2001-01-01

41

SUPPLEMENTARY COMPARISON: Final report of EUROMET.TS2 (projects EUROMET 391 and 712): Supplementary comparison of realizations of the indium freezing point  

Microsoft Academic Search

Comparisons of indium freezing point cells have been carried out by the EUROMET TC-THERM group as Projects Nos 391 and 712. The main objective was to establish the agreement between the realizations of the indium freezing point within different participating laboratories, to identify and eliminate possible discrepancies. The equipment has been made available by BNM-INM. Justervesenet coordinated project no 391,

C. Rauta; E. Renaot; M. H. Valin; M. Elgourdou; F. Adunka; A. van der Linden; A. Steiner; J. Bartu; M. Smid; M. Sindelar; E. Tegeler; Ute Noatsch; J.-U. Holtoug; V. Chimenti; M. Anagnostou; T. Weckstrøm; G. Sutton; R. Rusby; F. Pavese; P. P. M. Steur; P. Marcarino; M. J. de Groot; E. Filipe; I. Lobo; J. Ivarsson; S. Duris; J. Bojkovski; Miha Hiti; S. Ugur; A. K. Dogan; E. Grudniewicz

2008-01-01

42

Freeze tolerance, supercooling points and ice formation: comparative studies on the subzero temperature survival of limno-terrestrial tardigrades.  

PubMed

Many limno-terrestrial tardigrades live in unstable habitats where they experience extreme environmental conditions such as drought, heat and subzero temperatures. Although their stress tolerance is often related only to the anhydrobiotic state, tardigrades can also be exposed to great daily temperature fluctuations without dehydration. Survival of subzero temperatures in an active state requires either the ability to tolerate the freezing of body water or mechanisms to decrease the freezing point. Considering freeze tolerance in tardigrades as a general feature, we studied the survival rate of nine tardigrade species originating from polar, temperate and tropical regions by cooling them at rates of 9, 7, 5, 3 and 1 degrees C h(-1) down to -30 degrees C then returning them to room temperature at 10 degrees C h(-1). The resulting moderate survival after fast and slow cooling rates and low survival after intermediate cooling rates may indicate the influence of a physical effect during fast cooling and the possibility that they are able to synthesize cryoprotectants during slow cooling. Differential scanning calorimetry of starved, fed and cold acclimatized individuals showed no intraspecific significant differences in supercooling points and ice formation. Although this might suggest that metabolic and biochemical preparation are non-essential prior to subzero temperature exposure, the increased survival rate with slower cooling rates gives evidence that tardigrades still use some kind of mechanism to protect their cellular structure from freezing injury without influencing the freezing temperature. These results expand our current understanding of freeze tolerance in tardigrades and will lead to a better understanding of their ability to survive subzero temperature conditions. PMID:19251996

Hengherr, S; Worland, M R; Reuner, A; Brümmer, F; Schill, R O

2009-03-01

43

Working and Non-Working University Students: Anxiety, Depression, and Grade Point Average  

ERIC Educational Resources Information Center

This study explored the differences between 110 working and non-working students in terms of mental health, academic achievement, and perceptions about student employment. Anxiety and depression were measured by the Beck Anxiety Inventory and the Beck Depression Inventory-II. Academic achievement was measured by grade point average. Perceptions of…

Mounsey, Rebecca; Vandehey, Michael A.; Diekhoff, George M.

2013-01-01

44

Pour-point depression of crude oils by addition of tar sand bitumen  

Microsoft Academic Search

A process is described for reducing the pour point of a crude oil which comprises adding a pour-point depressant selected from the group consisting of a raw tar sands bitumen and hydrotreated tar sands bitumen to form a blend possessing a relatively lower pour point.

Soderberg

1988-01-01

45

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

SciTech Connect

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, .

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

46

Depression  

MedlinePLUS

... version of this page please turn Javascript on. Depression About Depression Click for more information Everyone feels blue or ... disorder," or "clinical depression." Click for more information Depression in Older Adults Important life changes that happen ...

47

Depression  

MedlinePLUS

... Work Group Reports Technology Assessments FS006, January 2009 Depression What is depression? Depression is a set of feelings of sadness, loss ... persist over time, for at least 2 weeks. Depression can be linked to alcohol and other drug ...

48

Water adsorption-desorption isotherms of two-dimensional hexagonal mesoporous silica around freezing point.  

PubMed

Zr-doped mesoporous silica with a diameter of approximately 3.8 nm was synthesized via an evaporation-induced self-assembly process, and the adsorption-desorption isotherms of water vapor were measured in the temperature range of 263-298 K. The measured adsorption-desorption isotherms below 273 K indicated that water confined in the mesopores did not freeze at any relative pressure. All isotherms had a steep curve, resulting from capillary condensation/evaporation, and a pronounced hysteresis. The hysteresis loop, which is associated with a delayed adsorption process, increased with a decrease in temperature. Furthermore, the curvature radius where capillary evaporation/condensation occurs was evaluated by the combined Kelvin and Gibbs-Tolman-Koening-Buff (GTKB) equations for the modification of the interfacial tension due to the interfacial curvature. The thickness of the water adsorption layer for capillary condensation was slightly larger, whereas that for capillary evaporation was slightly smaller than 0.7 nm. PMID:22041197

Endo, Akira; Yamaura, Toshio; Yamashita, Kyohei; Matsuoka, Fumio; Hihara, Eiji; Daiguji, Hirofumi

2012-02-01

49

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. ...

50

Depression  

MedlinePLUS

Depression is a serious medical illness that involves the brain. It's more than just a feeling of ... million people in the United States who have depression, the feelings do not go away. They persist ...

51

Depression  

MedlinePLUS

... to enjoy (including sex) Thinking about death or suicide Physical symptoms Changes in appetite (eating more than ... help prevent depression from coming back. Thoughts of suicide are common in people with depression. The risk ...

52

Depression  

MedlinePLUS Videos and Cool Tools

... strong that a depressed person may even consider suicide. Suicide and attempted suicide are very tragic consequences of depression. If a ... you realize that a loved one is contemplating suicide, you should contact a doctor immediately. The same ...

53

Freeze substitution followed by low melting point wax embedding preserves histomorphology and allows protein and mRNA localization techniques.  

PubMed

Fixation and embedding are major steps in tissue preservation for histological analysis. However, conventional fixatives like aldehyde-based solutions usually mask tissular epitopes preventing their immunolocalization. Alternative fixation methods used to avoid this drawback, such as cryopreservation, alcohol- or zinc salts-based fixatives do not efficiently preserve tissue and cell morphology. Likewise, paraffin and resin embedding, commonly used for thin sectioning, frequently damage epitopes due to the clearing agents and high temperatures needed along the embedding procedure. Alternatives like cryosectioning avoid the embedding steps but yield sections of poorer quality and are not suitable for all kinds of samples. To overcome these handicaps, we have developed a method that preserves histoarchitecture as well as tissue antigenic properties. This method, which we have named CryoWax, involves freeze substitution of the samples in isopentane and methanol, followed by embedding in low melting point polyester wax. CryoWax has proven efficient in obtaining thin sections of embryos and adult tissues from different species, including amphioxus, zebrafish, and mouse. CryoWax sections displayed optimal preservation of tissue morphology and were successfully immunostained for fixation- and temperature-sensitive antigens. Furthermore, CryoWax has been tested for in situ hybridization application, obtaining positive results. PMID:20830701

Durán, Iván; Marí-Beffa, Manuel; Santamaría, Jesús A; Becerra, José; Santos-Ruiz, Leonor

2011-05-01

54

Theoretical Analysis of Melting Point Depression of Pure Metals in Different Initial Configurations  

NASA Astrophysics Data System (ADS)

A general equation is derived for melting point depression (MPD) of pure metals, consisting of three terms: MPD due to high gas pressure, MPD due to high strain energy, and MPD due to small size of the metal. Particular equations are derived for different configurations of the solid metal, including grains embedded within a matrix. The equations obtained in this paper can be used to design nano-joining structures with improved MPD.

Kaptay, G.; Janczak-Rusch, J.; Pigozzi, G.; Jeurgens, L. P. H.

2014-05-01

55

Depression of pour points of vegetable oils by blending with diluents used for biodegradable lubricants  

Microsoft Academic Search

Low-temperature properties need improvement before vegetable oils can receive wider recognition as biodegradable lubricants.\\u000a Effects of dilution with major biodegradable fluids, namely poly alpha olefin (PAO 2), diisodecyl adipate (DIDA), and oleates,\\u000a as well as impact of pour point depressant (PPD), were investigated. Since solidification of mixed unsaturated triacylglycerols\\u000a is a complex thermodynamic process, the study was limited to pour

Svajus Asadauskas; Sevim Z. Erhan

1999-01-01

56

Thermocouple observations of melting and freezing plateaus for metal-carbon eutectics between the copper and palladium points  

Microsoft Academic Search

Melting and freezing plateaus were observed with type-R thermocouples for the metal-carbon eutectics Pd-C, Ni-C, and Fe-C. For Pd-C, no apparent difference between the melting and freezing temperatures was observed at a heating\\/cooling rate of 3 °C\\/min. For Ni-C, the difference was 0.4 °C, and for Fe-C, 1.6 °C. The freezing temperature for Fe-C showed dependence on cooling rate, and

Y. Yamada; F. Sakuma; A. Ono

2000-01-01

57

Periodic ice banding in freezing colloidal dispersions.  

PubMed

Concentrated colloidal alumina dispersions were frozen in a directional solidification apparatus that provides independent control of the freezing rate and temperature gradient. Two distinct steady-state modes of periodic ice banding were observed in the range of freezing rates examined. For each mode, the wavelength between successive bands of segregated ice decreases with increasing freezing rate. At low freezing rates (0.25-3 ?m s(-1)), the ice segregates from the suspension into ice lenses, which are cracklike in appearance, and there is visible structure in the layer of rejected particles in the unfrozen region ahead of the ice lenses. In this regime, we argue that compressive cryosuction forces lead to the irreversible aggregation of the rejected particles into a close-packed cohesive layer. The temperature in the aggregated layer is depressed below the bulk freezing point by more than 2 °C before the ice lenses are encountered; moreover, this undercooled region appears as a light-colored layer. The magnitude of the undercooling and the color change in this region both suggest the presence of pore ice and the formation of a frozen fringe. The possibility of a frozen fringe is supported by a quantitative model of the freezing behavior. At intermediate freezing rates, around 4 ?m s(-1), the pattern of ice segregation is disordered, coinciding with the disappearance of the dark- and light-colored layers. Finally, at high freezing rates (5-10 ?m s(-1)), there is a new mode of periodic ice banding that is no longer cracklike and is absent of any visible structure in the suspension ahead of the ice bands. We discuss the implications of our experimental findings for theories of ice lensing. PMID:23110707

Anderson, Anthony M; Worster, M Grae

2012-12-01

58

Depression.  

ERIC Educational Resources Information Center

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…

Strock, Margaret

59

Depression (PDQ)  

MedlinePLUS

General Information About Depression Key Points for This Section Depression is different from normal sadness. Some cancer patients may have a higher risk of depression. There are many medical conditions that can cause ...

60

Freezing point and solid-liquid interfacial free energy of Stockmayer dipolar fluids: A molecular dynamics simulation study  

NASA Astrophysics Data System (ADS)

Stockmayer fluids are a prototype model system for dipolar fluids. We have computed the freezing temperatures of Stockmayer fluids at zero pressure using three different molecular-dynamics simulation methods, namely, the superheating-undercooling method, the constant-pressure and constant-temperature two-phase coexistence method, and the constant-pressure and constant-enthalpy two-phase coexistence method. The best estimate of the freezing temperature (in reduced unit) for the Stockmayer (SM) fluid with the dimensionless dipole moment ?*=1, 2, 3 is 0.656 +/- 0.001, 0.726 +/- 0.002, and 0.835 +/- 0.005, respectively. The freezing temperature increases with the dipolar strength. Moreover, for the first time, the solid-liquid interfacial free energies ? of the fcc (111), (110), and (100) interfaces are computed 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, i.e., ?100 > ?110 > ?111.

Wang, Jun; Apte, Pankaj A.; Morris, James R.; Zeng, Xiao Cheng

2013-09-01

61

Freezing point and solid-liquid interfacial free energy of Stockmayer dipolar fluids: a molecular dynamics simulation study.  

PubMed

Stockmayer fluids are a prototype model system for dipolar fluids. We have computed the freezing temperatures of Stockmayer fluids at zero pressure using three different molecular-dynamics simulation methods, namely, the superheating-undercooling method, the constant-pressure and constant-temperature two-phase coexistence method, and the constant-pressure and constant-enthalpy two-phase coexistence method. The best estimate of the freezing temperature (in reduced unit) for the Stockmayer (SM) fluid with the dimensionless dipole moment ?*=1, ?2, ?3 is 0.656 ± 0.001, 0.726 ± 0.002, and 0.835 ± 0.005, respectively. The freezing temperature increases with the dipolar strength. Moreover, for the first time, the solid-liquid interfacial free energies ? of the fcc (111), (110), and (100) interfaces are computed 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, i.e., ?100 > ?110 > ?111. PMID:24070303

Wang, Jun; Apte, Pankaj A; Morris, James R; Zeng, Xiao Cheng

2013-09-21

62

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

NASA Technical Reports Server (NTRS)

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.

Albright, A. E.

1984-01-01

63

Freezing lake  

NSDL National Science Digital Library

Finite difference solution to mixed conduction-convection limited freezing of a 10 cm thick pool of water, with benchmark against analytical timescales. Requisite software: Gnumeric or Excel to open spreadsheets in source directory.

Powell, Adam C., IV

2005-02-23

64

Effects of temperatures near the freezing point on N2O emissions, denitrification and on the abundance and structure of nitrifying and denitrifying soil communities.  

PubMed

Climate warming in temperate regions may lead to decreased soil temperatures over winter as a result of reduced snow cover. We examined the effects of temperatures near the freezing point on N(2)O emissions, denitrification, and on the abundance and structure of soil nitrifiers and denitrifiers. Soil microcosms supplemented with NO3 - and/or NO3 - plus red clover residues were incubated for 120 days at -4 °C, -1 °C, +2 °C or +5 °C. Among microcosms amended with residues, N(2)O emission and/or denitrification increased with increasing temperature on Days 2 and 14. Interestingly, N(2)O emission and/or denitrification after Day 14 were the greatest at -1 °C. Substantial N(2) O emissions were only observed on Day 2 at +2 °C and +5 °C, while at -1 °C, N(2)O emissions were consistently detected over the duration of the experiment. Abundances of ammonia oxidizing bacteria (AOB) and archaea (AOA), Nitrospira-like bacteria and nirK denitrifiers were the lowest in soils at -4 °C, while abundances of Nitrobacter-like bacteria and nirS denitrifiers did not vary among temperatures. Community structures of nirK and nirS denitrifiers and Nitrobacter-like bacteria shifted between below-zero and above-zero temperatures. Structure of AOA and AOB communities also changed but not systematically among frozen and unfrozen temperatures. Results indicated shifts in some nitrifier and denitrifier communities with freezing and a surprising stimulation of N(2)O emissions at -1 °C when NO3 - and C are present. PMID:22882277

Wertz, Sophie; Goyer, Claudia; Zebarth, Bernie J; Burton, David L; Tatti, Enrico; Chantigny, Martin H; Filion, Martin

2013-01-01

65

Cloud Point Depression in Dilute Solutions of HEMA/DMAEMA Copolymers with Prescribed Composition Profiles and Gradient Strengths  

NASA Astrophysics Data System (ADS)

We have synthesized a random copolymer and gradient copolymers of hydroxyethyl methacrylate and dimethylaminoethyl methacrylate whose instantaneous compositions vary linearly and according to hyperbolic tangent (Tanh) functions along the backbones, all having similar molecular weights and overall compositions. The cloud point of the dilute solution of the random copolymer is 20.0^oC; the transparent-to-turbid transition occurs over 1.0^oC. Dilute solutions of linear gradient copolymers exhibit cloud point depressions of up to 3.5^oC and transition breadths of 1-3^oC compared to that of the random copolymer. The cloud points of dilute solutions of gradient copolymers with Tanh composition profiles are further suppressed by as much as 9.0^oC compared to that of the random copolymer. Our observations demonstrate the importance of monomer sequence distribution in altering the macroscopic solution properties of copolymers.

Gallow, Keith; Jhon, Young; Genzer, Jan; Loo, Yueh-Lin

2011-03-01

66

Liquidus Temperature Depression in Cryolitic Melts  

NASA Astrophysics Data System (ADS)

The electrolyte in Hall-Héroult cells for the manufacture of primary aluminum nominally contains only cryolite (Na3AlF6) with additions of AlF3, CaF2, and Al2O3. However, impurities are present, entering the process with the feedstock. The effect on the liquidus temperature by the impurities cannot be calculated correctly by the well-known equation for freezing-point depression in binary systems simply because the electrolyte cannot be regarded as a binary system. By extending the equation for freezing-point depression to the ternary system NaF-AlF3-B, it appeared that the acidity of the impurity B plays a major role. Some calculations were made using an ideal Temkin model, and for most types of impurities, the effect on the liquidus temperature will be larger in an industrial electrolyte than what can be estimated from the equation for freezing-point depression in cryolite. Experimental data on the liquidus temperature in the system Na3AlF6-AlF3-Al2O3-CaF2-MgF2 show that the effect of MgF2 on the liquidus temperature increases strongly with decreasing NaF/AlF3 molar ratio, and it is suggested that MgF2 forms an anion complex, probably MgF{4/2-}.

Solheim, Asbjørn

2012-08-01

67

Freezing and Food Safety  

MedlinePLUS

... JSR 286) Actions ${title} Loading... Freezing and Food Safety What Can You Freeze? Is Frozen Food Safe? Does Freezing Destroy Bacteria & Parasites? Freshness & Quality Nutrient Retention Enzymes Packaging Freezer Burn Color Changes Freeze Rapidly Freezer - Refrigerator Temperatures Freezer Storage ...

68

Freezing and Freeze-Drying  

Microsoft Academic Search

Most biological substances are unstable during storage owing to their high water content. This is why numerous attempts have been made over the last 100 years to prevent, by low temperature freezing, metabolic and biochemical degradations. The transformation of water into ice brings to an end all chemical reactions; however, it might also induce deleterious alterations into the delicate structure

L. Rey; N. W. Pirie; W. E. Whitman; N. Kurti

1975-01-01

69

Synergistic impacts of land-use change and soil property variation on non-point source nitrogen pollution in a freeze-thaw area  

NASA Astrophysics Data System (ADS)

Quantifying the non-point source (NPS) nitrogen pollution response to the varied land-use and soil properties in highly agricultural regions is critical for the proper management of NPS pollution. This study simulated the NPS nitrogen loading responses to variations of land-use and soil from 1979 to 2009. The Soil and Water Assessment Tool (SWAT) was used to model the NPS organic nitrogen and nitrate loading in a freeze-thaw area in northeast China. The temporal-spatial simulations of land-use in four periods indicated that the NPS nitrogen loading responded to the disappearance of wetlands and the conversion of uplands to paddy rice. After updating the soil data, the watershed NPS nitrogen loading decreased, and the spatial distribution of the loading indicated that the NPS organic nitrogen was more sensitive than was the nitrate to soil variation. F-tests were employed to assess the significance of each of the predictor variables in five types of scenarios. Overall, the results indicate that the watershed NPS nitrogen loading is sensitive to changes of soil and land-use, but soil changes have a more significant impact. The results of this study also suggest that temperature has significant effects on NPS nitrogen yield and that it caused the twin peaks in the temporal scale. Increasing the temperature above zero in April caused a temporal shift in soil water movement and transported nitrogen pollution earlier in the year, causing an increased loading in water before the summer irrigation, which is advantageous for NPS nitrogen pollution control.

Ouyang, Wei; Huang, Haobo; Hao, Fanghua; Guo, Bobo

2013-07-01

70

Depression in the cloud point of Tween in the presence of glycol additives and triblock polymers  

Microsoft Academic Search

Cloud point (C P) measurements of Tween 20 and Tween 80 were carried out in the presence of various glycol oligomers and triblock polymers (TBP). The cloud points of both Tween 20 and 80 decrease in the presence of both types of additives. Among the glycol oligomeric additives, ethylene glycol monobutyl ether was found to reduce the C P maximum.

Rakesh Kumar Mahajan; Jyoti Chawla; Mandeep Singh Bakshi

2004-01-01

71

Involvement of protein synthesis in the reconsolidation of memory at different time points after formation of conditioned reflex freezing in mice.  

PubMed

The aim of the present work was to study the involvement of protein synthesis in the reconsolidation of memory at different periods of time after training. In mice trained in a conditioned reflex freezing model, memory was reactivated by a reminder combined with administration of the protein synthesis inhibitor cycloheximide. The results showed that suppression of protein synthesis on reactivation of memory 3, 6, and 24 h and 14 and 30 days after training impaired acquired conditioned reflex freezing. These data provide evidence that memories retrieved by a reminder require protein-dependent reorganization at both short (3-6 h) and long (14-30 days) periods after training. PMID:17457537

Murav'eva, E V; Anokhin, K V

2007-05-01

72

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

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…

Tellinghuisen, Joel

2010-01-01

73

Depression, anxiety and their comorbidity in the Swedish general population: point prevalence and the effect on health-related quality of life  

PubMed Central

Background. Depression and anxiety disorders are major world-wide problems. There are no or few epidemiological studies investigating the prevalence of depression, generalized anxiety disorder and anxiety disorders in general in the Swedish population. Methods. Data were obtained by means of a postal survey administered to 3001 randomly selected adults. After two reminders response rate was 44.3%. Measures of depression and general anxiety were the 9-item Patient Health Questionnaire Depression Scale (PHQ-9) and the 7-item Generalized Anxiety Disorder Scale (GAD-7). The PHQ-9 identified participants who had experienced clinically significant depression (PHQ-9 ? 10), and who had a diagnosis of major depression (defined by using a PHQ-9 scoring algorithm). Clinically significant anxiety was defined as having a GAD-7 score ? 8. To specifically measure generalized anxiety disorder, the Generalized Anxiety Disorder Questionnaire-IV (GAD-Q-IV) was used with an established cut-off. Health-related quality of life was measured using the EuroQol (EQ-5D). Experiences of treatments for psychiatric disorders were also assessed. Results. Around 17.2% (95% CI: 15.1–19.4) of the participants were experiencing clinically significant depression (10.8%; 95% CI: 9.1–12.5) and clinically significant anxiety (14.7%; 95% CI: 12.7–16.6). Among participants with either clinically significant depression or anxiety, nearly 50% had comorbid disorders. The point prevalence of major depression was 5.2% (95% CI: 4.0–6.5), and 8.8% (95% CI: 7.3–10.4) had GAD. Among those with either of these disorders, 28.2% had comorbid depression and GAD. There were, generally, significant gender differences, with more women having a disorder compared to men. Among those with depression or anxiety, only between half and two thirds had any treatment experience. Comorbidity was associated with higher symptom severity and lower health-related quality of life. Conclusions. Epidemiological data from the Swedish community collected in this study provide point prevalence rates of depression, anxiety disorders and their comorbidity. These conditions were shown in this study to be undertreated and associated with lower quality of life, that need further efforts regarding preventive and treatment interventions.

Carlbring, Per; Heedman, ?sa; Paxling, Bjorn; Andersson, Gerhard

2013-01-01

74

Stability against freezing of aqueous solutions on early Mars.  

PubMed

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

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

2009-05-21

75

Involvement of protein synthesis in the reconsolidation of memory at different time points after formation of conditioned reflex freezing in mice  

Microsoft Academic Search

The aim of the present work was to study the involvement of protein synthesis in the reconsolidation of memory at different\\u000a periods of time after training. In mice trained in a conditioned reflex freezing model, memory was reactivated by a reminder\\u000a combined with administration of the protein synthesis inhibitor cycloheximide. The results showed that suppression of protein\\u000a synthesis on reactivation

E. V. Murav’eva; K. V. Anokhin

2007-01-01

76

Preservation of flavor in freeze dried green beans  

NASA Technical Reports Server (NTRS)

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.

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

1973-01-01

77

Freeze prediction model  

NASA Technical Reports Server (NTRS)

Measurements of wind speed, net irradiation, and of air, soil, and dew point temperatures in an orchard at the Rock Springs Agricultural Research Center, as well as topographical and climatological data and a description of the major apple growing regions of Pennsylvania were supplied to the University of Florida for use in running the P-model, freeze prediction program. Results show that the P-model appears to have considerable applicability to conditions in Pennsylvania. Even though modifications may have to be made for use in the fruit growing regions, there are advantages for fruit growers with the model in its present form.

Morrow, C. T. (principal investigator)

1981-01-01

78

Drought increases freezing tolerance of both leaves and xylem of Larrea tridentata.  

PubMed

Drought and freezing are both known to limit desert plant distributions, but the interaction of these stressors is poorly understood. Drought may increase freezing tolerance in leaves while decreasing it in the xylem, potentially creating a mismatch between water supply and demand. To test this hypothesis, we subjected Larrea tridentata juveniles grown in a greenhouse under well-watered or drought conditions to minimum temperatures ranging from -8 to -24 °C. We measured survival, leaf retention, gas exchange, cell death, freezing point depression and leaf-specific xylem hydraulic conductance (k?). Drought-exposed plants exhibited smaller decreases in gas exchange after exposure to -8 °C compared to well-watered plants. Drought also conferred a significant positive effect on leaf, xylem and whole-plant function following exposure to -15 °C; drought-exposed plants exhibited less cell death, greater leaf retention, higher k? and higher rates of gas exchange than well-watered plants. Both drought-exposed and well-watered plants experienced 100% mortality following exposure to -24 °C. By documenting the combined effects of drought and freezing stress, our data provide insight into the mechanisms determining plant survival and performance following freezing and the potential for shifts in L. tridentata abundance and range in the face of changing temperature and precipitation regimes. PMID:20825578

Medeiros, Juliana S; Pockman, William T

2011-01-01

79

Fundamentals of freeze-drying.  

PubMed

Given the increasing importance of reducing development time for new pharmaceutical products, formulation and process development scientists must continually look for ways to "work smarter, not harder." Within the product development arena, this means reducing the amount of trial and error empiricism in arriving at a formulation and identification of processing conditions which will result in a quality final dosage form. Characterization of the freezing behavior of the intended formulation is necessary for developing processing conditions which will result in the shortest drying time while maintaining all critical quality attributes of the freeze-dried product. Analysis of frozen systems was discussed in detail, particularly with respect to the glass transition as the physical event underlying collapse during freeze-drying, eutectic mixture formation, and crystallization events upon warming of frozen systems. Experiments to determine how freezing and freeze-drying behavior is affected by changes in the composition of the formulation are often useful in establishing the "robustness" of a formulation. It is not uncommon for seemingly subtle changes in composition of the formulation, such as a change in formulation pH, buffer salt, drug concentration, or an additional excipient, to result in striking differences in freezing and freeze-drying behavior. With regard to selecting a formulation, it is wise to keep the formulation as simple as possible. If a buffer is needed, a minimum concentration should be used. The same principle applies to added salts: If used at all, the concentration should be kept to a minimum. For many proteins a combination of an amorphous excipient, such as a disaccharide, and a crystallizing excipient, such as glycine, will result in a suitable combination of chemical stability and physical stability of the freeze-dried solid. Concepts of heat and mass transfer are valuable in rational design of processing conditions. Heat transfer by conduction--the dominant mechanism of heat transfer in freeze-drying--is inefficient at the pressures used in freeze-drying. Steps should be taken to improve the thermal contact between the product and the shelf of the freeze dryer, such as eliminating metal trays from the drying process. Quantitation of the heat transfer coefficient for the geometry used is a useful way of assessing the impact of changes in the system such as elimination of product trays and changes in the vial. Because heat transfer by conduction through the vapor increases with increasing pressure, the commonly held point of view that "the lower the pressure, the better" is not true with respect to process efficiency. The optimum pressure for a given product is a function of the temperature at which freeze-drying is carried out, and lower pressures are needed at low product temperatures. The controlling resistance to mass transfer is almost always the resistance of the partially dried solids above the submination interface. This resistance can be minimized by avoiding fill volumes of more than about half the volume of the container. The development scientist should also recognize that very high concentrations of solute may not be appropriate for optimum freeze-drying, particularly if the resistance of the dried product layer increases sharply with concentration. Although the last 10 years has seen the publication of a significant body of literature of great value in allowing development scientists and engineers to "work smarter," there is still much work needed in both the science and the technology of freeze-drying. Scientific development is needed for improving analytical methodology for characterization of frozen systems and freeze-dried solids. A better understanding of the relationship between molecular mobility and reactivity is needed to allow accurate prediction of product stability at the intended storage temperature based on accelerated stability at higher temperatures. This requires that the temperature dependence of glass transition-associated mobili

Nail, Steven L; Jiang, Shan; Chongprasert, Suchart; Knopp, Shawn A

2002-01-01

80

Avoid freeze-up of steam traps and their piping  

Microsoft Academic Search

This article addresses the problem of keeping steam traps free of ice in cold weather. The topics of the article include piping configurations and trap types that contribute to freezing, freeze damage, obstructions in piping, insulation of lines to retard freezing, common manifolds for heating of condensate, draining of low points, temperature-actuated devices, and water hammer damage.

OKeefe

1993-01-01

81

Freezing cold injury.  

PubMed

The pathogenesis of freezing cold injuries (FCI) is not yet entirely understood. Two possible hypothesis emerge: 1) Injury is a direct result of cryogenic insult to the cells. 2) Injury is secondary to vascular stasis which leads to anoxia. In clinical congelatio ice crystallization takes place in the EC-space. When water is transformed into ice, the osmolality in this compartment will increase leading to a passive diffusion of water from the IC-space. Cell dehydration modifies protein structure, alters membrane lipids and cellular pH leading to destructions incompatible with cell survival. Cold induces vasoconstriction of both arterioles and venules, which enhances peripheral filtration and raises plasma viscosity. The stability of red corpuscle aggregates increases and showers of emboli course microvessels. Finally progressive thrombosis will end up in anoxia. The indirect vascular effect has earlier been interpreted similar to that found in non-freezing injuries. Recent studies have, however, shown, that endothelial cells are very sensitive to freezing. The rheologic part of the pathogenesis therefore also seems to depend on a direct injury to cells. The development of FCI does not always depend on ambient temperature and duration of exposure but more to the heat loss subjected to exposed skin. Wind chill, humidity and wetness are all of significance in this matter. From a clinical point of view FCI are best subdivided into superficial and deep injuries. The superficial frostbite is limited to the skin and nearest subcutaneous tissue. A stringing, pinching pain is often the first symptom. The affected area becomes pale or waxy-white and numb.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1811585

Granberg, P O

1991-01-01

82

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

Microsoft Academic Search

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,

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

1994-01-01

83

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.

84

Study on the Realization of Indium Point  

NASA Astrophysics Data System (ADS)

Indium point cells are fabricated using ingots of various forms from a variety of sources (manufacturers). Using these cells, newly built indium point furnaces are evaluated and their reliability is confirmed. The indium point realizations based on the single solid-liquid method (SSL method) and multi solid-liquid method (MSL method) are evaluated. The effect of impurities in the ingots is evaluated from the dependency of the slope of the freezing curve on the change in furnace temperature, the indium point depression based on the impurity analysis, and the cell comparison. The results show equality among the cells. Based on the results obtained, the uncertainty in realizing the indium point using the described indium point cells and indium point furnaces is estimated. The new uncertainty budget introduces uncertainties coming from plateau repeatability and chemical impurity derived by the present work, the values of which are significantly lower than those adopted in the current calibration service.

Widiatmo, Januarius V.; Yamazawa, Kazuaki; Satou, Kouichi; Tamba, Jun; Arai, Masaru

85

The importance of COâ on freezing point measurements of fluid inclusions: evidence from active geothermal systems and implications for epithermal ore deposition  

Microsoft Academic Search

The authors show how the melting point of ice may be calculated for a fluid of known composites. Fluid inclusion ice-melting data from New Zealand geothermal fields correlate well with values calculated using the equation presented and the measured compositions of discharges from wells from which the inclusion samples were obtained. Loss of the dominant dissolved gas, COâ during boiling

J. W. Hedenquist; R. W. Henley

1985-01-01

86

Safely Freezing LTL  

Microsoft Academic Search

We consider the safety fragment of linear temporal logic with the freeze quantifier. The freeze quantifier is used to store a value from an infinite domain in a register for later comparison with other such val- ues. We show that, for one register, satisfiability, refinement and model checking problems are decidable. The main result in the paper is that sat-

Ranko Lazic

2006-01-01

87

Melting and freezing of water in cylindrical silica nanopores.  

PubMed

Freezing and melting of H(2)O and D(2)O in the cylindrical pores of well-characterized MCM-41 silica materials (pore diameters from 2.5 to 4.4 nm) was studied by differential scanning calorimetry (DSC) and (1)H NMR cryoporometry. Well-resolved DSC melting and freezing peaks were obtained for pore diameters down to 3.0 nm, but not in 2.5 nm pores. The pore size dependence of the melting point depression DeltaT(m) can be represented by the Gibbs-Thomson equation when the existence of a layer of nonfreezing water at the pore walls is taken into account. The DSC measurements also show that the hysteresis connected with the phase transition, and the melting enthalpy of water in the pores, both vanish near a pore diameter D* approximately equal to 2.8 nm. It is concluded that D* represents a lower limit for first-order melting/freezing in the pores. The NMR spin echo measurements show that a transition from low to high mobility of water molecules takes place in all MCM-41 materials, including the one with 2.5 nm pores, but the transition revealed by NMR occurs at a higher temperature than indicated by the DSC melting peaks. The disagreement between the NMR and DSC transition temperatures becomes more pronounced as the pore size decreases. This is attributed to the fact that with decreasing pore size an increasing fraction of the water molecules is situated in the first and second molecular layers next to the pore wall, and these molecules have slower dynamics than the molecules in the core of the pore. PMID:18825292

Jähnert, S; Vaca Chávez, F; Schaumann, G E; Schreiber, A; Schönhoff, M; Findenegg, G H

2008-10-21

88

Desalting of Seawater by Freezing.  

National Technical Information Service (NTIS)

The economics of the secondary refrigerant freezing process was evaluated with particular emphasis on large freezing plants. It was found that large economies resulted by using normal butane. A study of the secondary refrigerant freezing process using nor...

H. F. Wiegandt J. P. Leinroth P. Harriott

1968-01-01

89

Surface freezing of n-octane nanodroplets  

NASA Astrophysics Data System (ADS)

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.

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

2013-05-01

90

Freeze drying apparatus  

DOEpatents

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.

Coppa, Nicholas V. (Malvern, PA); Stewart, Paul (Youngstown, NY); Renzi, Ernesto (Youngstown, NY)

2001-01-01

91

Freeze drying method  

DOEpatents

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.

Coppa, Nicholas V. (Malvern, PA); Stewart, Paul (Youngstown, NY); Renzi, Ernesto (Youngstown, NY)

1999-01-01

92

Depression - resources  

MedlinePLUS

Resources - depression ... Depression is a medical condition. If you think you may be depressed, see a health care provider. ... following organizations are good resources of information on depression : American Psychological Association - www.apa.org/topics/depress/ ...

93

High-freezing-point fuel studies  

NASA Technical Reports Server (NTRS)

Considerable progress in developing the experimental and analytical techniques needed to design airplanes to accommodate fuels with less stringent low temperature specifications is reported. A computer technique for calculating fuel temperature profiles in full tanks was developed. The computer program is being extended to include the case of partially empty tanks. Ultimately, the completed package is to be incorporated into an aircraft fuel tank thermal analyser code to permit the designer to fly various thermal exposure patterns, study fuel temperatures versus time, and determine holdup.

Tolle, F. F.

1980-01-01

94

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

NSDL National Science Digital Library

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.

Aquarium, New E.

2011-01-01

95

Two-dimensional freezing criteria for crystallizing colloidal monolayers  

NASA Astrophysics Data System (ADS)

Video microscopy was employed to explore crystallization of colloidal monolayers composed of diameter-tunable microgel spheres. Two-dimensional (2D) colloidal liquids were frozen homogenously into polycrystalline solids, and four 2D criteria for freezing were experimentally tested in thermal systems for the first time: the Hansen-Verlet freezing rule, the Löwen-Palberg-Simon dynamical freezing criterion, and two other rules based, respectively, on the split shoulder of the radial distribution function and on the distribution of the shape factor of Voronoi polygons. Importantly, these freezing criteria, usually applied in the context of single crystals, were demonstrated to apply to the formation of polycrystalline solids. At the freezing point, we also observed a peak in the fluctuations of the orientational order parameter and a percolation transition associated with caged particles. Speculation about these percolated clusters of caged particles casts light on solidification mechanisms and dynamic heterogeneity in freezing.

Wang, Ziren; Alsayed, Ahmed M.; Yodh, Arjun G.; Han, Yilong

2010-04-01

96

Two-dimensional freezing criteria for crystallizing colloidal monolayers.  

PubMed

Video microscopy was employed to explore crystallization of colloidal monolayers composed of diameter-tunable microgel spheres. Two-dimensional (2D) colloidal liquids were frozen homogenously into polycrystalline solids, and four 2D criteria for freezing were experimentally tested in thermal systems for the first time: the Hansen-Verlet freezing rule, the Lowen-Palberg-Simon dynamical freezing criterion, and two other rules based, respectively, on the split shoulder of the radial distribution function and on the distribution of the shape factor of Voronoi polygons. Importantly, these freezing criteria, usually applied in the context of single crystals, were demonstrated to apply to the formation of polycrystalline solids. At the freezing point, we also observed a peak in the fluctuations of the orientational order parameter and a percolation transition associated with caged particles. Speculation about these percolated clusters of caged particles casts light on solidification mechanisms and dynamic heterogeneity in freezing. PMID:20423183

Wang, Ziren; Alsayed, Ahmed M; Yodh, Arjun G; Han, Yilong

2010-04-21

97

Scram or Freeze  

NSDL National Science Digital Library

In this outdoor activity and animal-role-play game, learners discover and uncover the hidden world of "cryptozoa"âorganisms such as spiders, salamanders and slugs that live under objects, like rocks and fallen tree trunks, or in concealed places. When uncovered, some cryptozoa scurry for cover ("scram"), while others remain motionless ("freeze"). Both behaviors help uncovered organisms escape from predators. In the game, learners take the roles of predator or prey and get to scram and freeze, and even growl, until all the prey are caught or reach "shelter." Learners also conduct a cryptozoa survey, by carefully upturning pieces of wood, leaves and rock to find and collect hidden animals. At the end, learners return all organisms to their original positions. The PDF includes safety precautions to protect both learners and the animals they uncover. To adapt the game for hearing impaired learners, instruction signs reading "scram" and "freeze" could be used instead of verbal instructions.

Science, Lawrence H.

1981-01-01

98

Percolation with Constant Freezing  

NASA Astrophysics Data System (ADS)

We introduce and study a model of percolation with constant freezing (PCF) where edges open at constant rate 1 , and clusters freeze at rate ? independently of their size. Our main result is that the infinite volume process can be constructed on any amenable vertex transitive graph. This is in sharp contrast to models of percolation with freezing previously introduced, where the limit is known not to exist. Our interest is in the study of the percolative properties of the final configuration as a function of ? . We also obtain more precise results in the case of trees. Surprisingly the algebraic exponent for the cluster size depends on the degree, suggesting that there is no lower critical dimension for the model. Moreover, even for ?

Mottram, Edward

2014-04-01

99

Percolation with Constant Freezing  

NASA Astrophysics Data System (ADS)

We introduce and study a model of percolation with constant freezing ( PCF) where edges open at constant rate , and clusters freeze at rate independently of their size. Our main result is that the infinite volume process can be constructed on any amenable vertex transitive graph. This is in sharp contrast to models of percolation with freezing previously introduced, where the limit is known not to exist. Our interest is in the study of the percolative properties of the final configuration as a function of . We also obtain more precise results in the case of trees. Surprisingly the algebraic exponent for the cluster size depends on the degree, suggesting that there is no lower critical dimension for the model. Moreover, even for , it is shown that finite clusters have algebraic tail decay, which is a signature of self organised criticality. Partial results are obtained on , and many open questions are discussed.

Mottram, Edward

2014-06-01

100

Freezing of Lennard-Jones-type fluids  

SciTech Connect

We put forward an approximate method to locate the fluid-solid (freezing) phase transition in systems of classical particles interacting via a wide range of Lennard-Jones-type potentials. This method is based on the constancy of the properly normalized second derivative of the interaction potential (freezing indicator) along the freezing curve. As demonstrated recently it yields remarkably good agreement with previous numerical simulation studies of the conventional 12-6 Lennard-Jones (LJ) fluid [S.A.Khrapak, M.Chaudhuri, G.E.Morfill, Phys. Rev. B 134, 052101 (2010)]. In this paper, we test this approach using a wide range of the LJ-type potentials, including LJ n-6 and exp-6 models, and find that it remains sufficiently accurate and reliable in reproducing the corresponding freezing curves, down to the triple-point temperatures. One of the possible application of the method--estimation of the freezing conditions in complex (dusty) plasmas with ''tunable'' interactions--is briefly discussed.

Khrapak, Sergey A. [Max-Planck-Institut fuer Extraterrestrische Physik, D-85741 Garching (Germany); Joint Institute for High Temperatures, 125412 Moscow (Russian Federation); Chaudhuri, Manis; Morfill, Gregor E. [Max-Planck-Institut fuer Extraterrestrische Physik, D-85741 Garching (Germany)

2011-02-07

101

Freezing curve-based monitoring to quickly evaluate the viability of biological materials subject to freezing or thermal injury.  

PubMed

This paper is aimed at investigating the roles of freezing dynamics of a liquid droplet to characterize the properties of the material. In particular, freezing curve-based monitoring was proposed to quickly evaluate the viability of biological materials subject to freezing, re-warming, or other kinds of injury, which is an extremely important issue in practices such as cryobiology, hyperthermia, or freshness evaluation of bio-samples. An integrated micro analysis device was fabricated which is simple in structure and cheap to make. Preliminary freezing results demonstrated that minor changes in a biological material due to freezing or warming injury might result in a significant deviation of its freezing curve from that of the intact biomaterials. Several potential thermal indexes to quantify the material features were pointed out. Further, experiments were performed on some freezing and thawing processes of small amount of water on a cooling surface to test the effects of droplet sizes, measurement sites, cooling strength, and cooling geometry, etc., on the freezing responses of a water droplet. Their implementation in developing a new micro analysis system were suggested. This freezing curve-based monitoring method may open a new strategy for the evaluation of biomaterials subject to destruction in diverse fields. PMID:12844203

Liu, Jing; Zhou, Yi-Xin

2003-09-01

102

Animal Anti-Freeze  

NSDL National Science Digital Library

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.

Science, Lawrence H.

1982-01-01

103

Visualization of freezing damage.  

PubMed

Freeze-cleaving can be used as a direct probe to examine the ultrastructural alterations of biological material due to freezing. We examined the thesis that at least two factors, which are oppositely dependent upon cooling velocity, determine the survival of cells subjected to freezing. According to this thesis, when cells are cooled at rates exceeding a critical velocity, a decrease in viability is caused by the presence of intracellular ice; but cells cooled at rates less than this critical velocity do not contain appreciable amounts of intracellular ice and are killed by prolonged exposure to a solution that is altered by the presence of ice. As a test of this hypothesis, we examined freeze-fractured replicas of the yeast Saccharomyces cerevisiae after suspensions had been cooled at rates ranging from 1.8 to 75,000 degrees C/min. Some of the frozen samples were cleaved and replicated immediately in order to minimize artifacts due to sample handling. Other samples were deeply etched or were rewarmed to -20 degrees C and recooled before replication. Yeast cells cooled at or above the rate necessary to preserve maximal viability ( approximately 7 degrees C/min) contained intracellular ice, whereas cells cooled below this rate showed no evidence of intracellular ice. PMID:4572921

Bank, H; Mazur, P

1973-06-01

104

Mechanistic study into the enhanced transdermal permeation of a model beta-blocker, propranolol, by fatty acids: a melting point depression effect.  

PubMed

Transdermal permeation of propranolol through human skin in the presence of fatty acid (lauric, capric) penetration enhancers has been investigated. Thermal analysis showed that binary mixtures of propranolol with either fatty acid were not simple mechanical mixtures of the two components. Propranolol formed 1:1 molar addition compounds with both lauric and capric acids; the addition compound produced from propranolol and lauric acid (m.p. 79 degrees C) also developed eutectic systems with both propranolol (m.p. 54 degrees C) and lauric acid (m.p. 16 degrees C). Similarly, the addition compound made from propranolol and capric acid (m.p. 97 degrees C) formed eutectic systems with propranolol (m.p. 83 degrees C) and capric acid (m.p. 15 degrees C). Infrared analyses indicated that the addition compounds were fatty acid salts of the beta-blocker. The nature of the species permeating through human epidermal membranes from binary mixtures of propranolol with the fatty acids was investigated using a novel attenuated total reflectance Fourier transform infrared method. There was no clear difference in permeation rates of the fatty acids compared with the beta-blocker, suggesting that the permeating species was the intact addition compound. The influence of melting point depression of the beta-blocker fatty acid systems on transdermal permeation was predicted from a mathematical model; predicted and experimentally determined data correlated well thus providing an alternative explanation as to the mode of action of these permeation enhancers. PMID:11337176

Stott, P W; Williams, A C; Barry, B W

2001-05-21

105

Freezing and anoxia tolerance of slugs: a metabolic perspective.  

PubMed

Freezing survival was assessed in three species of terrestrial slugs, a holarctic but native North American species, Deroceras laeve, and two species introduced from Europe, D. reticulatum and Arion circumscriptus. The introduced species showed very poor freezing survival. Supercooling points of the introduced species were quite high ( approximately -3 degrees C) and their freezing survival was very poor, limited to short-term freezing at -1.2 to -1.5 degrees C and low ice contents (23-44%). D. laeve showed a significant elevation of supercooling point between slugs collected in the autumn (-4.8 degrees C +/- 0.5) and those collected early in the spring (-3.1 degrees C +/- 0.4). This species also showed substantial freezing survival which was greater for spring-collected slugs (100% survival of 1 h freezing at -2 degrees C with an ice content of 65%) than for autumn animals (100% survival for 1 h at -1 degrees C with approximately 40% ice). Carbohydrate and amino acid responses to freezing and anoxia exposures were compared in the two Deroceras species. D. laeve showed a strong hyperglycemic response to freezing, a 100-fold increase in glucose levels that suggested that glucose may have a cryoprotective function in this species. D. reticulatum did not accumulate glucose and neither species produced glycerol or lactate. Both species showed typical responses to anoxia (aspartate and glutamate catabolism, alanine and succinate accumulation) and D. laeve also showed this pattern during freezing, suggesting a natural switch to anaerobiosis to support freezing survival. PMID:17628806

Storey, Kenneth B; Storey, Janet M; Churchill, Thomas A

2007-11-01

106

Mechanisms of Freezing lnjuly in Cellular Leve  

NASA Astrophysics Data System (ADS)

The mechanisms of freezing injury in living cells were reviewed. The freezing injury takes place by at least two different factors depending upon cooling rate, those are intracellular freezing and extracellular freezing. The freezing injury caused by extracellular freezing also takes place by two different factors, those are direct and indirect effects by the formation of extracellular ice. These different stresses by freezing cause different damages on the plasma membranes in the same cell. Furthermore, freezing of different cell results in different form of membrane damage. Thus, the occurrence of freezing injury takes place by diverse mechanisms depending upon not only different freezing stresses but also difference of cell type.

Fujikawa, Seizo

107

Oocyte freezing: here to stay?  

PubMed

Oocyte freezing is an established technology but, in contrast to embryo freezing, it has very limited application in clinical IVF programmes. Is there a chance that oocyte freezing will become an integrated routine in assisted reproductive technology? The delicate cytological architecture of the oocyte with a cold-sensitive spindle and a hardening zona have made the frozen oocyte 'unwanted' in assisted reproductive technology. Nevertheless, empirical improvements in freezing protocols and the use of ICSI for fertilization have led to an increasing number of live births. This mitigates against a simple ban on oocyte freezing. While efficiency of oocyte freezing can certainly be further improved by basic research, it is clear that there are humanitarian reasons for considering oocyte freezing as a future fully utilized assisted reproductive technology. The storage of the female genome as a particulate entity can provide an alternative in case of moral, ethical, legal or religious concerns about embryo freezing. Oocyte freezing can also offer hope for oocyte donation and preservation of fertility for women facing ovarian loss. The message is one of cautious optimism when looking for a place for oocyte freezing in routine assisted reproductive technology. PMID:14640378

Van der Elst, Josiane

2003-01-01

108

Freezing and melting of hydrogen confined in nanoporous silica  

NASA Astrophysics Data System (ADS)

Thermodynamic properties of condensed hydrogen in geometric confinement remain poorly understood. Here, we use relaxation calorimetry to study solidification and melting of H2 in a series of Vycor-type nanoporous silica glasses with interconnected pores with average diameters in a wide range of ?100–3000 Å. We find that the depression of freezing and melting temperatures for this quantum system follows the classical Gibbs–Thomson-like behavior, scaling inversely with the pore size when correlated to pore diameters measured directly by electron microscopy, rather than conventional gas sorption techniques. The shapes of pore size distributions derived from hydrogen thermoporometry are, however, more complex than those measured by gas sorption. The ratio between temperatures of the depression of freezing and melting suggests that the actual pore geometry in Vycor-type nanoporous glasses deviates from cylindrical.

Kucheyev, S. O.; Van Cleve, E.; Worsley, M. A.

2014-06-01

109

Freezing and melting of hydrogen confined in nanoporous silica.  

PubMed

Thermodynamic properties of condensed hydrogen in geometric confinement remain poorly understood. Here, we use relaxation calorimetry to study solidification and melting of H2 in a series of Vycor-type nanoporous silica glasses with interconnected pores with average diameters in a wide range of ?100-3000 ?. We find that the depression of freezing and melting temperatures for this quantum system follows the classical Gibbs-Thomson-like behavior, scaling inversely with the pore size when correlated to pore diameters measured directly by electron microscopy, rather than conventional gas sorption techniques. The shapes of pore size distributions derived from hydrogen thermoporometry are, however, more complex than those measured by gas sorption. The ratio between temperatures of the depression of freezing and melting suggests that the actual pore geometry in Vycor-type nanoporous glasses deviates from cylindrical. PMID:24823921

Kucheyev, S O; Van Cleve, E; Worsley, M A

2014-06-01

110

Freeze-Tolerant Condensers  

NASA Technical Reports Server (NTRS)

Two condensers designed for use in dissipating heat carried by working fluids feature two-phase, self-adjusting configurations such that their working lengths automatically vary to suit their input power levels and/or heat-sink temperatures. A key advantage of these condensers is that they can function even if the temperatures of their heat sinks fall below the freezing temperatures of their working fluids and the fluids freeze. The condensers can even be restarted from the frozen condition. The top part of the figure depicts the layout of the first condenser. A two-phase (liquid and vapor) condenser/vapor tube is thermally connected to a heat sink typically, a radiatively or convectively cooled metal panel. A single-phase (liquid) condensate-return tube (return artery) is also thermally connected to the heat sink. At intervals along their lengths, the condenser/vapor tube and the return artery are interconnected through porous plugs. This condenser configuration affords tolerance of freezing, variable effective thermal conductance (such that the return temperature remains nearly constant, independently of the ultimate sink temperature), and overall pressure drop smaller than it would be without the porous interconnections. An additional benefit of this configuration is that the condenser can be made to recover from the completely frozen condition either without using heaters, or else with the help of heaters much smaller than would otherwise be needed. The second condenser affords the same advantages and is based on a similar principle, but it has a different configuration that affords improved flow of working fluid, simplified construction, reduced weight, and faster recovery from a frozen condition.

Crowley, Christopher J.; Elkouhk, Nabil

2004-01-01

111

On the Freezing and Melting Behavior of the Eutectic Pt-C  

NASA Astrophysics Data System (ADS)

The feasibility of referring to freezing as an alternative to melting for defining the eutectic transition temperature has been studied using two Pt-C cells constructed at NIM, one of a sleeve type, and the other of a hybrid type, including support. Freezing and melting experiments have been done by varying the offset of the furnace temperature T furn with respect to the nominal eutectic temperature T E used to freeze the fixed point with offsets ( T furn- T E)freeze from -5 K to -40 K, followed by melting at a fixed offset ( T furn- T E)melt = + 20 K. Plotting the liquidus temperatures T liq,freeze and T liq,melt obtained for freezing and melting against {(T_E-T_furn)^{1/2}_freeze} resulted in linear relations for both cells, allowing extrapolation toward T liq,freeze(0) and T liq, melt(0). For the cells Pt-C5# and Pt-C6# under study: T liq,melt(0)- T liq,freeze(0) = 10 mK and 20 mK, respectively, with a standard uncertainty of 30 mK for both T liq,melt(0) and T liq,freeze(0). The coherence of the results obtained for melting and freezing indicates that freezing can be used, as an alternative to melting, to define the liquidus temperature T liq(0) of the eutectic Pt-C.

Dong, W.; Bloembergen, P.; Wang, T.; Duan, Y. Y.

2011-12-01

112

A Study of Corona Discharges at Water Drops Over the Freezing Temperature Range  

Microsoft Academic Search

Foul weather corona have been observed to behave differently at temperatures above and below the freezing point1.2. Generally speaking, the discharge activities are much more intensive at temperatures above than below the freezing point. Such behaviour of the discharge is so far associated with the differences in the physical properties of water in its liquid and solid phases. No detailed

J. Luan Phan-Cong; Pol Pirotte; Rene Brunelle; N. G. Trinh

1974-01-01

113

Freezing of Nonwoody Plant Tissue  

PubMed Central

Temperature recordings of the freezing of plant tissues include two plateaus or regions of reduced slope. During the second of these, small positive spikes were observed. When a completely frozen tissue was thawed and refrozen, neither the second plateau nor the spikes were recorded. Both were present, however, if the initial freezing had been terminated before the second plateau had been reached. The spikes appear to represent the release of heat of crystallization during the freezing of individual cells. Such a freezing and thawing cycle destroys the ability of the cells to remain supercooled in the presence of the ice that is formed as the first plateau is recorded.

Brown, M. S.; Pereira, E. Sa B.; Finkle, Bernard J.

1974-01-01

114

Impact of Freezing Process on Salt Diffusivity of Seafood: Application to Salmon ( Salmo salar ) Using Conventional and Pressure Shift Freezing  

Microsoft Academic Search

The depression of the melting temperature of ice under pressure permits to obtain a rapid freezing of foods. The expected\\u000a benefit lies in reduced water diffusion from the intra- toward the extracellular media, resulting in a reduced drip loss during\\u000a thawing. Beside, the modification of the cellular structure induced by ice formation may affect the mass diffusivity of the\\u000a flesh.

Ebrahim Alizadeh; Nicolas Chapleau; Marie de-Lamballerie; Alain Le-Bail

2009-01-01

115

Performance Characteristics of an Isothermal Freeze Valve  

SciTech Connect

This document discusses performance characteristics of an isothermal freeze valve. A freeze valve has been specified for draining the DWPF melter at the end of its lifetime. Two freeze valve designs have been evaluated on the Small Cylindrical Melter-2 (SCM-2). In order to size the DWPF freeze valve, the basic principles governing freeze valve behavior need to be identified and understood.

Hailey, A.E.

2001-08-22

116

[Severe depression : psychoanalysis].  

PubMed

The indication for psychoanalysis in severe depression is not clear. And yet, demands for this type of intervention are increasing, despite the absence of any form of consensus on the subject. Freud considered depression as a failure of analytical efforts and, based on this observation, revised his theory, in particular to include the notions of narcissism and the death drive. Many analysts have been reluctant to follow his teachings on this last point and provide depressed patients with analytical-type therapies aimed at restoring narcissism. Melanie Klein pushed Freud's ideas about depression even further and brought such therapies back to the heart of analytical practice. Jacques Lacan took the debate to another level by proposing an overhaul of the principles on which analysis has been based. Today, while following certain precautionary rules, true psychoanalyses can be proposed to patients with severe depression, whether of the bipolar, recurring or even neurotic type that can reach this level of severity. PMID:20141799

Bouvet de la Maisonneuve, O

2009-12-01

117

Freezing and thawing porous media: experimental study with a dielectric capacitive method  

NASA Astrophysics Data System (ADS)

A capacitive sensor-based apparatus has been used to study the ice/water phase change in consolidated porous media subjected to freezing and thawing. This technique relies on the dielectric properties of water, ice, air, and the mineral substrate in the radio-frequency range. It gives directly the freezing and thawing temperature depressions and indirectly provides an estimation of pore size distribution through the Gibbs-Thomson relation. It also holds good promise for evaluating the amount of liquid water in frozen porous media by combining drying and freezing tests. To cite this article: T. Fen-Chong, A. Fabbri, C. R. Mecanique 333 (2005).

Fen-Chong, Teddy; Fabbri, Antonin

2005-05-01

118

Development of Freeze Dried Vegetables.  

National Technical Information Service (NTIS)

The development of freeze dried vegetables to be used in the Apollo food system is discussed. After the initial selection and screening of vegetables, several types of freeze dried vegetables were prepared in small batches. From these small batches, two v...

R. W. Larson

1970-01-01

119

Combined impacts of freeze-thaw processes on paddy land and dry land in Northeast China.  

PubMed

The quantity of spring snowmelt infiltration and runoff, which affects the hydrology of the freeze zone, depends on the antecedent soil water content (SWC) conditions at the time of the soil's freezing. An understanding of the characteristics of frozen soil is essential for spring sowing in the agricultural freeze zones. The main goal of this study was to evaluate the differences in the freeze-thaw process and the freeze-thaw-induced water redistribution between the paddy and dry lands in a freeze zone. For this purpose, a field study was conducted in the winter of 2011-2012 for two types of farmlands in Northeast China. To illustrate the soil's frost dynamics over time, the measured SWCs at different depths (15, 30, 60, and 90 cm) were transformed into different expressions including the SWC dynamic, the frozen soil's profile, and the freezing and thawing front trace. The freezing characteristics in the paddy land, in contrast to that in the dry land, had a higher freezing point temperature, a larger amount of water movement to the upper layer, and a 2.76 mm larger accumulation of water in the upper layer. However, the increase of SWC (which is equivalent to thawing) was evidently faster than the decrease of SWC (which is equivalent to freezing). The water in the frozen soil's profile was most likely redistributed towards the freezing front before soil temperature (ST) falls below the freezing point. The findings may partially explain the soil's freeze-thaw characteristics for the different stages as well as the combined impact of these characteristics with farmland use types on soil hydrology; the findings may also provide a foundation for forecasting the hydrologic response of the freeze-thaw process and provide guidance for management strategies dealing with seasonally frozen agricultural soils. PMID:23584030

Chen, Siyang; Ouyang, Wei; Hao, Fanghua; Zhao, Xuchen

2013-07-01

120

Freezing Phenomena in Adsorbed Water as Studied by NMR  

NASA Astrophysics Data System (ADS)

The freezing of water adsorbed on high-surface-area materials such as silica gel, controlled-pore glass, and activated charcoal is investigated with NMR methods. Part of the pore water freezes at the temperature predicted by the Kelvin equation and the rest of the water does not freeze in the sense that it does not assume the structure of ice on cooling below this freezing point. This bound water exhibits a distribution of correlation times, and information about the width of this distribution is obtained. Values for the activation enthalpy of the bound water are also deduced. An alternative method for the determination of the pore volume of an adsorbent is proposed and it is shown that. for adsorbents with small pores ( r < 100 Å), this method results in a much better estimate for the total pore volume than the more common mercury-intrusion method.

Overloop, K.; Vangerven, L.

121

Freezing of living cells  

SciTech Connect

It can be calculated that a living cell will survive more than 5000 years at -196/sup 0/C. This ability to essentially stop biological time has important implications in medicine and agriculture, and in biological research. In medicine the chief implications are in the banking of transplantable tissues and organs and in in vitro fertilization. In agriculture the applications stem in part from the role of frozen embryos in amplifying the number of calves produced by high quanlity cows. The problem is how can cells survive both the cooling to such very low temperatures and the return to normal temperatures. The answers involve fundamental characteristics of cells such as the permeability of their surface membranes to water and solutes. These characteristics determine whether or not cells undergo lethal internal ice formation and other response during freezing and thawing. 27 refs., 12 figs.

Mazur, P.

1985-01-01

122

A new ST-segment elevation myocardial infarction equivalent pattern? Prominent T wave and J-point depression in the precordial leads associated with ST-segment elevation in lead aVr.  

PubMed

Certain acute coronary syndrome electrocardiographic (ECG) patterns, which do not include ST-segment elevation, are indicative of acute coronary syndrome caused by significant arterial occlusion; these patterns are, of course, associated with significant risk to the patient and mandate a rapid response from the health care team. One such high-risk ECG pattern includes the association of the prominent T wave and J-point depression producing ST-segment depression seen in the precordial leads coupled with ST-segment elevation in lead aVr. This ECG presentation is associated with significant left anterior descending artery obstruction. We report the case of a patient with this ECG presentation who progressed over a very short time to ST-segment elevation myocardial infarction of the anterior wall. PMID:24176590

Goebel, Mathew; Bledsoe, Joseph; Orford, James L; Mattu, Amal; Brady, William J

2014-03-01

123

Freeze-drying fungi using a shelf freeze-drier.  

PubMed

Lyophilization, the removal of water by freezing and then volatilization at low pressure and temperature, has been employed as a standard long-term preservation method for many filamentous fungi. The method outlined involves the use of standard shelf freeze-drying and skimmed milk as a suspending solution/lyoprotectant. This approach has been employed to freeze-dry the majority of the 50,000 fungal strains that have been successfully lyophilized at the Centraal bureau voor Schimmelcultures (CBS) culture collection (http://www.cbs.knaw.nl/). PMID:18080466

Tan, C Shu-hui; van Ingen, Cor W; Stalpers, Joost A

2007-01-01

124

Unipolar Depression  

Microsoft Academic Search

Unipolar depression is characterized by mood dysregulation that is manifested in recurrent affective episodes over the lifetime\\u000a of an individual. This chapter covers the epidemiology, pathology, genetics, and brain circuitry associated with unipolar\\u000a depression. In addition, animal models of depression that have been useful in characterizing neurobiological causes for depression\\u000a and development of new treatments are reviewed. Effective treatments exist

Julie A. Blendy; Irwin Lucki

125

Adolescent Depression.  

ERIC Educational Resources Information Center

Affective disorder is characterized by maladaptive changes in mood, attitudes, energy level, and physical status. These changes constitute the basic dimensions of depression. Depression results from a combination of genetic and experiential factors. There are sex differences and age differences with regard to depression, and there is a high…

Evans, Dina M.

126

A NEW FREEZING-ULTRAMICROTOME  

PubMed Central

The difficulties in sectioning frozen biological objects for electron microscopic investigations are overcome by Steere's freezing-etching method. In order to test this method and to open up a wide field of application, the new freezing-ultramicrotome has been designed. The apparatus consists of the combination of an ultramicrotome with freezing-drying and shadow-casting installations in the same vacuum container. The preliminary results show, on the one hand, the practicability of all preparational steps and, on the other, that it is possible to resolve internal structures of cell organelles and even macromolecular patterns.

Moor, H.; Muhlethaler, K.; Waldner, H.; Frey-Wyssling, A.

1961-01-01

127

Biomimetic Materials by Freeze Casting  

NASA Astrophysics Data System (ADS)

Natural materials, such as bone and abalone nacre, exhibit exceptional mechanical properties, a product of their intricate microstructural organization. Freeze casting is a relatively simple, inexpensive, and adaptable materials processing method to form porous ceramic scaffolds with controllable microstructural features. After infiltration of a second polymeric phase, hybrid ceramic-polymer composites can be fabricated that closely resemble the architecture and mechanical performance of natural bone and nacre. Inspired by the narwhal tusk, magnetic fields applied during freeze casting can be used to further control architectural alignment, resulting in freeze-cast materials with enhanced mechanical properties.

Porter, Michael M.; Mckittrick, Joanna; Meyers, Marc A.

2013-06-01

128

Evolution of freezing susceptibility and freezing tolerance in terrestrial arthropods  

Microsoft Academic Search

Abstract – Arthropods have evolved,various adaptations to survive adverse seasons and it has long been discussed why some arthropods are freezing-susceptible and some are freezing-tolerant. However, which mode of frost resistance came,first during the course of evolution? A commonly,held opinion is that no choice of strategy has been offered in evolution, because each species of arthropod may have its own

Ecology Écologie; Philippe Vernon; Guy Vannier

129

Freezing of supercooled water nanodroplets  

NASA Astrophysics Data System (ADS)

All three states of water play important roles in nature, from thermostating the atmosphere to providing reactive surfaces environments. The rates at which transitions between the phases occur, the degree to which pure liquid water can be supercooled, and the solid phases that form are all fundamentally interesting questions with strong atmospheric relevance. We have followed and characterized the nucleation, growth, and subsequent freezing of pure water droplets formed in a supersonic nozzle apparatus using both Small Angle X-ray Scattering (SAXS) and Fourier Transform Infrared Spectroscopy (FTIR). Because the droplets have radii r between 3 nm and 6 nm, and the cooling rates are on the order of 5E5 K/s, liquid water only begins to freeze below approximately 215 K. These temperatures are well below the homogeneous freezing limit for bulk water. The experiments show the expected decrease in freezing temperature with decreasing droplet size, or alternatively, with increasing droplet internal pressure.

Wyslouzil, Barbara

2013-03-01

130

Freezing of Aqueous Polyvinylpyrrolidone Solutions.  

National Technical Information Service (NTIS)

The freezing of aqueous polyvinylpyrrolidone solutions was studied by means of differential thermal analysis, dilatometry and calorimetry. A differential thermal analysis apparatus for use at low temperatures was constructed. A fast method for the determi...

H. H. G. Jellinek S. Y. Fok

1967-01-01

131

Depressive Disorders During Pregnancy  

PubMed Central

OBJECTIVE To estimate the prevalence of major and minor depression, panic disorder, and suicidal ideation during pregnancy while also identifying factors independently associated with antenatal depressive disorders. METHODS In this prospective study, participants were 1,888 women receiving ongoing prenatal care at a university obstetric clinic from January 2004 through January 2009. Prevalence of psychiatric disorders was measured using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria based on the Patient Health Questionnaire. Multiple logistic regression identified factors associated with probable major depressive disorder and any depressive disorder. RESULTS Antenatal depressive disorders were present in 9.9% with 5.1% (97) meeting criteria for probable major depression and 4.8% (90) meeting criteria for probable minor depression. Panic disorder was present in 3.2% (61), and current suicidal ideation was reported by 2.6% (49). Among patients with probable major depression, 29.5% (28) reported current suicidal ideation. Psychosocial stress (odds ratio [OR], 1.29; 95% confidence interval [CI], 1.21–1.36), domestic violence (OR 3.45; 95% CI 1.46–8.12), chronic medical conditions (OR 3.05; 95% CI 1.63–5.69), and race (Asian: OR 5.81; 95% CI 2.55–13.23; or African American: OR 2.98; 95% CI 1.24–7.18) each significantly increased the odds of probable antepartum major depressive disorder, whereas older age (OR 0.92; 95% CI 0.88–0.97) decreased the odds. Factors associated with odds of any depression were similar overall except that Hispanic ethnicity (OR 2.50; 95% CI 1.09–5.72) also independently increased the odds of any depression. CONCLUSION Antenatal major and minor depressive disorders are common and significantly associated with clinically relevant and identifiable risk factors. By understanding the high point prevalence and associated factors, clinicians can potentially improve the diagnosis and treatment rates of serious depressive disorders in pregnant women.

Melville, Jennifer L.; Gavin, Amelia; Guo, Yuqing; Fan, Ming-Yu; Katon, Wayne J.

2011-01-01

132

Preparation of the nematode-trapping fungus, Arthrobotrys oligospora, for scanning electron microscopy by freeze substitution.  

PubMed

A freeze-substitution technique for preparing fungal specimens for scanning electron microscopy is described. This involves cryofixation in liquid nitrogen, freeze substitution in methanol at -20 degrees C and critical-point drying. The trapping complexes and conidiophores of the nematophagous fungus Arthrobotrys oligospora are well preserved and retain their normal three-dimensional arrangement. PMID:2352273

Wharton, D A; Murray, D S

1990-04-01

133

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

PubMed

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

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

1994-08-01

134

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

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

135

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

PubMed Central

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.

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

2009-01-01

136

Geriatric Depression in Primary Care  

PubMed Central

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.

Park, Mijung; Unutzer, Jurgen

2011-01-01

137

Measuring and modeling hemoglobin aggregation below the freezing temperature.  

PubMed

Freezing of protein solutions is required for many applications such as storage, transport, or lyophilization; however, freezing has inherent risks for protein integrity. It is difficult to study protein stability below the freezing temperature because phase separation constrains solute concentration in solution. In this work, we developed an isochoric method to study protein aggregation in solutions at -5, -10, -15, and -20 °C. Lowering the temperature below the freezing point in a fixed volume prevents the aqueous solution from freezing, as pressure rises until equilibrium (P,T) is reached. Aggregation rates of bovine hemoglobin (BHb) increased at lower temperature (-20 °C) and higher BHb concentration. However, the addition of sucrose substantially decreased the aggregation rate and prevented aggregation when the concentration reached 300 g/L. The unfolding thermodynamics of BHb was studied using fluorescence, and the fraction of unfolded protein as a function of temperature was determined. A mathematical model was applied to describe BHb aggregation below the freezing temperature. This model was able to predict the aggregation curves for various storage temperatures and initial concentrations of BHb. The aggregation mechanism was revealed to be mediated by an unfolded state, followed by a fast growth of aggregates that readily precipitate. The aggregation kinetics increased for lower temperature because of the higher fraction of unfolded BHb closer to the cold denaturation temperature. Overall, the results obtained herein suggest that the isochoric method could provide a relatively simple approach to obtain fundamental thermodynamic information about the protein and the aggregation mechanism, thus providing a new approach to developing accelerated formulation studies below the freezing temperature. PMID:23808610

Rosa, Mónica; Lopes, Carlos; Melo, Eduardo P; Singh, Satish K; Geraldes, Vitor; Rodrigues, Miguel A

2013-08-01

138

Freeze-dried microarterial allografts  

SciTech Connect

Rehydrated freeze-dried microarterial allografts were implanted to bridge arterial defects using New Zealand White rabbits as the experimental model. Segments of artery from the rabbit ear and thigh were harvested and preserved for a minimum of 2 weeks after freeze-drying. These allografts, approximately 1 mm in diameter and ranging from 1.5 to 2.5 cm in length, were rehydrated and then implanted in low-pressure and high-pressure arterial systems. Poor patency was noted in low-pressure systems in both allografts and autografts, tested in 12 rabbits. In the high-pressure arterial systems, allografts that were freeze-dried and reconstituted failed in a group of 10 rabbits with an 8-week patency rate of 30 percent. Gamma irradiation in an effort to reduce infection and antigenicity of grafts after freeze-drying was associated with a patency rate of 10 percent at 8 weeks in this system in another group of 10 rabbits. Postoperative cyclosporin A therapy was associated with a patency rate of 22.2 percent in the high-pressure arterial system in a 9-rabbit group. Control autografts in this system in a group of 10 rabbits showed a 100 percent patency at 8 weeks. Microarterial grafts depend on perfusion pressure of the vascular bed for long-term patency. Rehydrated freeze-dried microarterial allografts do not seem to function well in lengths of 1 to 2.5 cm when implanted in a high-pressure arterial system. Freeze-dried arterial allografts are probably not antigenic.

Raman, J.; Hargrave, J.C.

1990-02-01

139

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

NASA Technical Reports Server (NTRS)

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.

Cutbirth, J. Michael

2012-01-01

140

Freezing kinetics in overcompressed water  

Microsoft Academic Search

The transformation of water into ice is among the most common first order phase transitions occurring in nature, but it is far from being an ordinary one. Water has unusual physical properties both as a liquid and as a solid due largely to hydrogen bonding effects, which also play a major role in determining the characteristics of its freezing kinetics.

Marina Bastea; Sorin Bastea; John Reaugh; David Reisman

2007-01-01

141

Programmed-Temperature Normal Freezing  

Microsoft Academic Search

A normal freezing apparatus is described where the cooling-bath temperature can be programmed between 0.5 × 10 and 6.0°C\\/mm. Runs with n-hexadecane\\/n-tetradecane test mixtures indicate that improved efficiencies result from programming the cooling bath during the run.

T. H. Gouw

1967-01-01

142

Freezing Tolerance in Mytilus Edulis.  

National Technical Information Service (NTIS)

Mytilus edulis tolerates freezing to a tissue temperature of -10 deg C, while Venus mercenaria tolerates only -6 deg C. In both species, tissues are injured when 64 per cent of cellular water has been moved to form ice. In Mytilus, 20 percent of cell wate...

R. J. Williams

1969-01-01

143

Repeated Freeze-Thaw Cycles in Cryosurgery  

Microsoft Academic Search

FREEZING temperatures have been in use in surgery for many years as a means of local tissue destruction. Recent experimental investigation has shown that such freezing will give a reproducible area of cell death provided factors such as the temperature and the duration of application are constant. Additional virtues have been claimed for repeated, as opposed to single, freeze-thaw cycles

William Gill; James Fraser; David C. Carter

1968-01-01

144

Molten salt freeze seal. Final report  

Microsoft Academic Search

This report documents the results of the testing performed at Sandia National Laboratory, Albuquerque, New Mexico, on the applicability of a sodium freeze seal type valve stem in a molten salt environment. The freeze seal tests consisted of cycling the valve stem at set temperature intervals, checking the temperature distribution for freeze plug location, and verifying the actuator forces. In

Corugedo

1985-01-01

145

Depression (lesson)  

NSDL National Science Digital Library

Students reveal their preconceptions about depression, then use G2C Online to learn about symptoms of the disorder, genes, and neurotransmitters associated with it, and challenges involved in diagnosis and treatment.

2009-04-14

146

Postpartum depression  

MedlinePLUS

... alcohol, take illegal substances, or smoke (these also cause serious medical health risks for the baby) Did not plan the pregnancy, or had mixed feelings about the pregnancy Had depression, bipolar disorder or an anxiety disorder before your pregnancy, or ...

147

Postpartum Depression  

MedlinePLUS Videos and Cool Tools

... approximately half a million women who are at risk of developing postpartum depression. So, clearly this is an important condition to the public health of this country, these are prevalent conditions that ...

148

Adolescent Depression  

PubMed Central

Depression in adolescence and adulthood is common, afflicting up to 20 percent of these populations. It represents a significant public health concern and is associated with considerable suffering and functional impairment. Adolescent-onset depression tends to be a particularly malignant and recalcitrant condition, increasing the likelihood of recurrence and chronicity in adulthood. Clinical presentations for various medical and psychiatric conditions, as well as reactions to psychosocial stressors, can mimic or confound the picture of depression in adolescents. Therefore, careful assessment and differential diagnosis is essential. Effective treatments, both pharmacological and psychosocial in nature, exist, and so early detection and intervention is paramount. This article presents an overview of optimal prevention, assessment, and clinical decision-making strategies for managing depression in adolescents.

Cook, Mary N.; Peterson, John; Sheldon, Christopher

2009-01-01

149

[Bipolar depression and unipolar depression: differential diagnosis in clinical practice].  

PubMed

When assessing a patient with depression it is crucial not to miss a diagnosis of bipolar depression. In this review we suggest that it can be achieved, first, by consistently usingstandardised diagnostic criteria (e.g., DSM-IV-TR or ICD 10) and, second, by ascertaining the presence of some clinical features. The latter include previous episodes of mood elevation, current or past episodes of psychotic depression, onset of recurrent depressive disorder before the age of 25, a strong family history of mood disorder and suicide, lack of response or "wearing off" of response to well conducted antidepressant treatment, and an unusually fast response to antidepressants with features of elation. Although more and better research is required to establish the validity, sensitivity, specificity, and predictive value of each one of these features we suggest that from a practical point of view they would increase clinicians' awareness of bipolar depression. PMID:20919490

Leyton, Fanny; Barrera, Alvaro

2010-06-01

150

Denaturation of ~nzyme Protein by Freeze-Thawing and Freeze-Drying  

Microsoft Academic Search

The effects of freeze-thawing and freeze-drying on catalase, one of globular proteins, were examined for the purpose of investigating relations of the confor­ mation of protein to its stability against freeze-thawing and freeze-drying. Also the water content of the freeze-dried egg albumin, a representative protein, was measured with or without some additives, for the clarification of the mechanism of their

Naofumi HANAFUSA

151

Heat pump with freeze-up prevention  

DOEpatents

What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid prevents freeze up of the second heat exchanger by keeping the temperature above the dew point; and, optionally, provides heat for efficient operation.

Ecker, Amir L. (Dallas, TX)

1981-01-01

152

Freeze indicators with a controlled temperature response  

US Patent & Trademark Office Database

A freeze indicator can include an indicator dispersion having an aqueous liquid medium and organic material indicator particles dispersed in the aqueous liquid medium. The indicator dispersion can have an initial appearance before freezing and an irreversibly different appearance after freezing and can exhibit a freeze-onset temperature of about -1.9.degree. C. or higher. Some factors helpful to providing a relatively high freeze onset temperature are employment of a proteinaceous ice-nucleating agent, control of pH, use of a protein stabilizer and control of the ratio of protein stabilizer to ice-nucleating agent.

2012-02-28

153

Freeze Technology for Nuclear Applications - 13590  

SciTech Connect

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)

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

154

Managing your depression - teens  

MedlinePLUS

Recognizing depression in your teen; Helping your teen with depression ... treatment for major depressive disorder in children and adolescents: US Preventive Services Task Force Recommendation Statement. Pediatrics . ...

155

Freeze chromatography method and apparatus  

DOEpatents

A freeze chromatography method and apparatus are provided which enable separation of the solutes contained in a sample. The apparatus includes an annular column construction comprising cylindrical inner and outer surfaces defining an annular passage therebetween. One of the surfaces is heated and the other cooled while passing an eluent through the annular passageway so that the eluent in contact with the cooled surface freezes and forms a frozen eluent layer thereon. A mixture of solutes dissolved in eluent is passed through the annular passageway in contact with the frozen layer so that the sample solutes in the mixture will tend to migrate either toward or away the frozen layer. The rate at which the mixture flows through the annular passageway is controlled so that the distribution of the sample solutes approaches that at equilibrium and thus a separation between the sample solutes occurs. 3 figs.

Scott, C.D.

1987-04-16

156

Optimal Freeze Cycle Length for Renal Cryotherapy  

PubMed Central

Purpose To our knowledge the optimal freeze cycle length in renal cryotherapy is unknown. Ten-minute time based freeze cycles were compared to temperature based freeze cycles to ?20C. Materials and Methods Laparoscopic renal cryotherapy was performed on 16 swine. Time based trials consisted of a double 10-minute freeze separated by a 5-minute thaw. Temperature based trials were double cycles of 1, 5 or 10-minute freeze initiated after 1 of 4 sensors indicated ?20C. A 5-minute active thaw was used between freeze cycles. Control trials consisted of cryoneedle placement for 25 minutes without freeze or thaw. Viability staining and histological analysis were done. Results There was no difference in cellular necrosis between any of the temperature based freeze cycles (p = 0.1). Time based freeze cycles showed more nuclear pyknosis, indicative of necrosis, than the 3 experimental freeze cycles for the renal cortex (p = 0.05) but not for the renal medulla (p = 0.61). Mean time to ?20C for freeze cycle 1 was 19 minutes 10 seconds (range 9 to 46 minutes). In 4 of 21 trials (19%) ?20C was never attained despite freezing for 25 to 63 minutes. Conclusions There was no difference in immediate cellular necrosis among double 1, 5 or 10-minute freeze cycles. Cellular necrosis was evident on histological analysis for trials in which ?20C was attained and in freeze cycles based on time alone. With a standard 10-minute cryoablation period most treated parenchyma 1 cm from the probe never attained ?20C. Cell death appeared to occur at temperatures warmer than ?20C during renal cryotherapy.

Young, Jennifer Lee; Khanifar, Elham; Narula, Navneet; Ortiz-Vanderdys, Cervando Gerardo; Kolla, Surendra Babu; Pick, Donald Lowell; Sountoulides, Petros George; Kaufmann, Oskar Grau; Osann, Kathryn Elizabeth; Huynh, Victor Buu; Kaplan, Adam Geoffrey; Andrade, Lorena Aurora; Louie, Michael Ken; McDougall, Elspeth Marguerita; Clayman, Ralph Victor

2014-01-01

157

[Depression in dementia with Lewy bodies].  

PubMed

Depression is a risk factor for dementia in general, including Alzheimer's disease (AD), its premorbid signs are commonly observed, and the morbidity of depression is higher in dementia patients. Dementia with Lewy bodies (DLB) is considered to have an even higher depression prevalence and premorbid depression rate than other dementias such as AD. This led to depression being listed as a supportive feature in the 2005 criteria for the clinical diagnosis of DLB. However, studies investigating the difference in depression between AD and DLB failed to show consistent results. We examined the Geriatric Depression Scale score, which is designed specifically to rate depression in the elderly, for DLB and AD patients. The scores for DLB patients were twice as high as those for AD patients. There was no correlation between the GDS score and age, sex, or Mini-Mental Sate Examination scores. Depression-specific symptoms were more frequent in the DLB group than non-specific symptoms, while less than one third of DLB patients with very high GDS scores were diagnosed with depression or prescribed antidepressants for depressive symptoms. Other researchers reported that depression of DLB was associated with a higher prevalence of psychiatric symptoms other than major depression, and suggested that depression of DLB might be a part of psychiatric syndrome. There has been no systematic study on the validity or risk of pharmacological therapy, as well as the necessity of intervention, for depression or a high GDS score in DLB. Therefore, intervention must rely on the clinical decision of each doctor. In spite of the paucity of current findings, studies on depression of DLB may play a key role in the elucidation of its neuropathology and psychopathology and offer a new view point on understanding depression itself. PMID:24450145

Sakai, Kazuo; Yamane, Yumiko; Yamamoto, Yasuji; Maeda, Kiyoshi

2013-01-01

158

Effect of stress on melting and freezing in nanopores.  

PubMed

A thermodynamic treatment of the freezing of fluids confined to nanosized closed pores is presented. The model includes the effects of pressure in the liquid, the volume change on solidification, and the strain energy in both the solidifying material and the wall material. When applied to the system of Pb droplets in Al, the model predicts an elevation of the melting point, in agreement with experiment. PMID:16486845

Hoyt, J J

2006-02-01

159

Depression and Smoking  

MedlinePLUS

... Tools » Depression Basics » Depression and Smoking Depression and Smoking Why is depression more common in smokers? Nobody ... towards a healthier, new lifestyle. Start Today Quitting Smoking Happens one craving at a time. one monday ...

160

Ultrafast microfluidic mixer and freeze-quenching device.  

PubMed

The freeze-quenching technique is extremely useful for trapping meta-stable intermediates populated during fast chemical or biochemical reactions. The application of this technique, however, is limited by the long mixing time of conventional solution mixers and the slow freezing time of cryogenic fluids. To overcome these problems, we have designed and tested a novel microfluidic silicon mixer equipped with a new freeze-quenching device, with which reactions can be followed down to 50 micros. In the microfluidic silicon mixer, seven 10-microm-diameter vertical pillars are arranged perpendicular to the flow direction and in a staggered fashion in the 450-pL mixing chamber to enhance turbulent mixing. The mixed-solution jet, with a cross section of 10 microm x 100 microm, exits from the microfluidic silicon mixer with a linear flow velocity of 20 m/s. It instantaneously freezes on one of two rotating copper wheels maintained at 77 K and is subsequently ground into an ultrafine powder. The ultrafine frozen powder exhibits excellent spectral quality and high packing factor and can be readily transferred between spectroscopic observation cells. The microfluidic mixer was tested by the reaction between azide and myoglobin at pH 5.0. It was found that complete mixing was achieved within the mixing dead time of the mixer (20 micros), and the first observable point for this coupled device was determined to be 50 micros, which is approximately 2 orders of magnitude faster than commercially available instruments. PMID:14710815

Lin, Yu; Gerfen, Gary J; Rousseau, Denis L; Yeh, Syun-Ru

2003-10-15

161

Coagulation size of freezable water in poly(vinyl alcohol) hydrogels formed by different freeze\\/thaw cycle periods  

Microsoft Academic Search

The coagulation size of freezable water in a poly(vinyl alcohol) (PVA) hydrogel was investigated as a function of the freeze\\/thaw cycle period using thermal analysis. The melting temperature of ice in the gel shifted to a lower temperature than that of normal ice. This temperature depression can be interpreted in terms of the coagulation size of freezable water in the

Tatsuro Nakano; Takahiko Nakaoki

2011-01-01

162

The effects of IL2R? knockout on depression and contextual memory  

PubMed Central

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.

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

2010-01-01

163

The initial freezing temperature of foods at high pressure.  

PubMed

The Pure water (P,T)-phase diagram is known in the form of empirical equations or tables from nearly a century as a result of Bridgman's work. However, few data are available on other aqueous systems probably due to the difficulty of high-pressure measurements. As an alternative, six approaches are presented here to obtain the food phase diagrams in the range of pressure 0.1-210 MPa. Both empirical and theoretical methods are described including the use of an artificial neural network (ANN). Experimental freezing points obtained at the laboratory of the authors and from literature are statistically compared to the calculated ones. About 400 independent freezing data points of aqueous solutions, gels, and foods are analysed. A polynomial equation is the most accurate and simple method to describe the entire melting curve. The ANN is the most versatile model, as only one model allows the calculation of the initial freezing point of all the aqueous systems considered. Robinson and Stokes' equation is successfully extended to the high pressures domain with an average prediction error of 0.4 degrees C. The choice of one approach over the others depends mainly on the availability of experimental data, the accuracy required and the intended use for the calculated data. PMID:18409115

Guignon, B; Torrecilla, J S; Otero, L; Ramos, A M; Molina-García, A D; Sanz, P D

2008-04-01

164

The Richards Function Applied to Data from Freezing Tests of Growing Shoots  

Microsoft Academic Search

~~~~ Frost resistance of growing Salix viminalis 1. shoots was deter- mined by rating mortality percentage under two commonly used freezing conditions: a condition in which plants were encased in crushed ice and another in which plants were moistened with tap water prior to freezing. The mortality-temperature data were fitted with a logistic function (having a fixed inflection point halfway

Heinrich A. von Fircks; Theo Verwijst

165

Depression - elderly  

MedlinePLUS

... be hard to detect. Common symptoms such as fatigue, appetite loss, and trouble sleeping can be part of the aging process or a physical illness. As a result, early depression may be ignored, or confused with other conditions that are common in the elderly.

166

Postpartum Depression  

MedlinePLUS

What are the postpartum blues? About 2–3 days after childbirth, some women begin to feel depressed, anxious, and upset. They may feel angry with ... a baby These feelings, often called the postpartum blues , may come and go in the first few ...

167

Characteristics of sugar surfactants in stabilizing proteins during freeze-thawing and freeze-drying.  

PubMed

Sugar surfactants with different alkyl chain lengths and sugar head groups were compared for their protein-stabilizing effect during freeze-thawing and freeze-drying. Six enzymes, different in terms of tolerance against inactivation because of freeze-thawing and freeze-drying, were used as model proteins. The enzyme activities that remained after freeze-thawing and freeze-drying in the presence of a sugar surfactant were measured for different types and concentrations of sugar surfactants. Sugar surfactants stabilized all of the tested enzymes both during freeze-thawing and freeze-drying, and a one or two order higher amount of added sugar surfactant was required for achieving protein stabilization during freeze-drying than for the cryoprotection. The comprehensive comparison showed that the C10-C12 esters of sucrose or trehalose were the most effective through the freeze-drying process: the remaining enzyme activities after freeze-thawing and freeze-drying increased at the sugar ester concentrations of 1-10 and 10-100 ?M, respectively, and increased to a greater extent than for the other surfactants at higher concentrations. Results also indicate that, when a decent amount of sugar was also added, the protein-stabilizing effect of a small amount of sugar ester through the freeze-drying process could be enhanced. PMID:24797557

Imamura, Koreyoshi; Murai, Katsuyuki; Korehisa, Tamayo; Shimizu, Noriyuki; Yamahira, Ryo; Matsuura, Tsutashi; Tada, Hiroko; Imanaka, Hiroyuki; Ishida, Naoyuki; Nakanishi, Kazuhiro

2014-06-01

168

Relationship between the freezing points and structure of aqueous solutions  

Microsoft Academic Search

UDC 532.77 The aqueous nonelectrolyte systems CsHlzN 4- HaG, DMFA - HzO, and C 6 HlzN 4 -n-C4 HgOH- HzO have been studied by the cryoscopic method over a wide range of concentrations. The diagrams obtained have been interpreted on the basis of the assumption that there is a direct relationship between the crystallization temperatures and the structural changes in

A. A. Énnan; V. A. Lapshin

1972-01-01

169

Alternating Current Corona in Foul Weather II - Below Freezing Point  

Microsoft Academic Search

The mechanism of ac corona caused by the presence of ice particles is shown. Two kinds of precipitation are distinguished: the snow-like and hail-like forms. Conditions of snowcover formation on transmission-line conductors are analyzed. This cover may result in the highest corona energy losses, caused mainly by steady pulseless corona in the positive, and Trichel impulses in the negative, half-cycle.

L. Boulet; L. Cahill; B. J. Jakubczyk

1966-01-01

170

Metabolic Activity of Permafrost Bacteria below the Freezing Point  

PubMed Central

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.

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

2000-01-01

171

Maternal Depression and Infant Temperament Characteristics  

PubMed Central

One hundred-thirty-nine women participated in this longitudinal study from the third trimester of pregnancy through 8-months postpartum. Women completed depression scales at several time points and rated their infant’s characteristics and childcare stress at 2- and 6-months postpartum. Mothers’ reports of infant temperament were significantly different for depressed and non-depressed mothers, with depressed mothers reporting more difficult infants at both measurement points. These differences remained after controlling for histories of maternal abuse or prenatal anxiety, which occurred more often in the depressed mothers. There were no significant differences in childcare stress or perceived support between the groups. Infant temperament and childcare stress did not change over time. Recommendations for practice include consistent ongoing evaluations of the “goodness of fit” within the dyad and exploring interventions for depressed mothers that provide guidance about interactions with their infants and the appropriateness of the infant behaviors.

McGrath, Jacqueline M.; Records, Kathie; Rice, Michael

2008-01-01

172

Freeze Drying: Potential for Powdered Nanoparticulate Product  

Microsoft Academic Search

Nanoparticles were prepared by using an emulsion solvent evaporation method. Further, the drying of an anti-cancer drug of proprietary nature (nanosized) was carried out by a freeze-drying technique to get a free-flowing powder. A systematic approach was developed to study the freeze-drying technique for polymeric nanoparticles. Initially, the freeze-thawing experiments were carried out with varying concentrations of cryoprotectants to screen

V. V. Patil; P. P. Dandekar; V. B. Patravale; B. N. Thorat

2010-01-01

173

Freeze coring soft sediments in tropical lakes  

Microsoft Academic Search

A new freeze corer is described that is specifically designed for operation in warm tropical lakes. It combines the standard wedge-shaped freeze-on container with a 20-liter thermos from which pellets of solid CO2 descend into the wedge to replace those that have sublimated. This extends the duration of effective freezing from ~20 to ~45 min, sufficient to form an adequate

Dirk Veerschuren

2000-01-01

174

Measuring freezing tolerance: survival and regrowth assays.  

PubMed

Screening plants for freezing tolerance under tightly controlled conditions is an invaluable technique for studying freezing tolerance and selecting for improved winterhardiness. Artificial freezing tests of cereal plants historically have used isolated crown and stem tissue prepared by "removing all plant parts 3 cm above and 0.5 cm below the crown tissue" (Fowler et al., Crop Sci 21:896-901, 1981). Here, we describe a method of conducting freezing tolerance tests using intact plants grown in small horticultural containers, including suggested methods for collecting and analyzing the data. PMID:24852624

Skinner, Daniel Z; Garland-Campbell, Kimberly

2014-01-01

175

Triple point of Lennard-Jones fluid in slit nanopore: Solidification of critical condensate  

NASA Astrophysics Data System (ADS)

We report the results of a molecular dynamics simulation that looked for the triple point of Lennard-Jones fluid in slit-shaped nanopores. The simulation method employed for this purpose is able to maintain vapor-liquid coexistence in a nanopore at a specific equilibrium bulk-phase pressure. The triple point is the freezing point of the critical condensate. The triple-point temperature could be higher or lower than the bulk triple point, depending on the pore size. This is thought to be due to two opposing factors: the elevating effect of the pore-wall potential energy, and the depressing effect of the capillary condensate's tensile condition. Because of the cancellation, the deviation of the triple-point temperature from the bulk triple-point temperature was not considered significant. The pressure of the triple point, however, was significantly different from that of the bulk triple point. A simple model to describe the triple point is developed and shown to agree well with the results of the simulation. The importance of the two factors in nanoscale pores, which cannot be described by the classic Gibbs-Thomson equation, is emphasized.

Kanda, Hideki; Miyahara, Minoru; Higashitani, Ko

2004-04-01

176

Effect of freeze-drying, freezing and frozen storage of blood plasma on fibrin network characteristics  

Microsoft Academic Search

Introduction: We investigated the effect of freezing, freeze-drying and the duration of frozen storage of blood plasma on fibrin network characteristics of clots subsequently produced. Materials and methods: Fibrin network characteristics of clots made from freeze-dried and frozen plasma were compared to those made from fresh plasma. Freeze-dried pooled plasma was reconstituted and frozen each month for 4 months to

Marlien Pieters; Johann C Jerling; John W Weisel

2002-01-01

177

Role of saccharides for the freeze-thawing and freeze drying of liposome  

Microsoft Academic Search

For the preservation of liposomes, freeze-thawing and freeze-drying have been studied by various workers with saccharides (SA) and a freeze-dried liposome preparation is now commercially available. However, the mechanism of stabilizing action of SA in these processes, especially freeze-drying, is not yet fully understood. The interaction of egg yolk phosphatidylcholine (EPC: liquid crystaline state) and DPPC (gel state) liposomes with

Koichiro Miyajima

1997-01-01

178

Mechanisms of deterioration of nutrients. [of freeze dried foods  

NASA Technical Reports Server (NTRS)

Methods which produce freeze dried foods of improved quality were examined with emphasis on storage stability. Specific topics discussed include: microstructure of freeze dried systems, investigation of structural changes in freeze dried systems, artificial food matrices, osmotic preconcentration to yield improved quality freeze dried fruits, and storage stability of osmotically preconcentrated freeze dried fruits.

Karel, M.; Flink, J. M.

1976-01-01

179

Depression: Fact Sheet for Parents  

MedlinePLUS

... Care, second edition Depression: A Fact Sheet for Parents What is depression? • Depression is a set of ... of depression? • Teens with one or more depressed parents are more likely to develop depression (the effects ...

180

Executive functioning moderates the relationship between motivation and adolescent depressive symptoms.  

PubMed

We investigated the association between adolescent depressive symptoms and components of executive functioning (EF), including planning (Tower of London), set-shifting (Wisconsin Card Sorting Task), and inhibition (Stop Signal Task) in a community sample of 12-14 year olds. Further, EF was tested as a moderator of motivation (as operationalized by revised Reinforcement Sensitivity Theory) effects on depressive symptoms. Results suggested that planning ability was associated with depressive symptoms. Furthermore, planning ability moderated the relationship between motivation (fight-flight- freeze system; FFFS) and depressive symptoms, such that among adolescents with poor planning ability the FFFS positively predicted depressive symptoms, but among adolescents with strong planning ability the FFFS negatively predicts depressive symptoms. Neither set-shifting nor inhibition was associated with depressive symptoms. Findings highlight the need to consider multiple components of EF and to integrate motivational and executive dysfunction models to the study of depression. PMID:23105161

Vergara-Lopez, Chrystal; Lopez-Vergara, Hector I; Colder, Craig R

2013-01-01

181

Executive functioning moderates the relationship between motivation and adolescent depressive symptoms  

PubMed Central

We investigated the association between adolescent depressive symptoms and components of executive functioning (EF), including planning (Tower of London), set-shifting (Wisconsin Card Sorting Task), and inhibition (Stop Signal Task) in a community sample of 12–14 year olds. Further, EF was tested as a moderator of motivation (as operationalized by revised Reinforcement Sensitivity Theory) effects on depressive symptoms. Results suggested that planning ability was associated with depressive symptoms. Furthermore, planning ability moderated the relationship between motivation (fight-flight- freeze system; FFFS) and depressive symptoms, such that among adolescents with poor planning ability the FFFS positively predicted depressive symptoms, but among adolescents with strong planning ability the FFFS negatively predicts depressive symptoms. Neither set-shifting nor inhibition was associated with depressive symptoms. Findings highlight the need to consider multiple components of EF and to integrate motivational and executive dysfunction models to the study of depression.

Vergara-Lopez, Chrystal; Lopez-Vergara, Hector I.; Colder, Craig R.

2012-01-01

182

Influence of formulation pH and suspension state on freezing-induced agglomeration of aluminum adjuvants.  

PubMed

Freezing and thawing of vaccines containing aluminum adjuvants can lead to formation of aggregates and loss in vaccine potency. We sought to understand whether and to what extent the freeze-thaw damage to aluminum adjuvants would differ based on suspension state (flocculation and settlement) at the time of freezing. As flocculation and settlement characteristics of aluminum adjuvants are driven largely by the electrostatic charges on the adjuvant particles, which, in turn, are strongly influenced by the pH of the suspension, we conducted freeze-thaw studies on both Adjuphos and Alhydrogel™ samples at three pH levels (4, 6.5, and 7.2) in buffer solutions with 9% sucrose. Significantly less aggregation occurred in the buffered sucrose solutions at the pH furthest from the aluminum adjuvant point of zero charge during slow freezing at -20°C. The freezing-induced aggregation for the samples with 9% sucrose at each pH was minimal during fast freezing at -70°C and -115°C. Suspensions that were flocculated and settled to a greater extent experienced the most freeze-thaw aggregation, whereas suspensions that were frozen before significant flocculation and settlement occurred showed little or no aggregation. Because pH of formulation can affect flocculation and settling time, it indirectly affects the extent of freeze-thaw aggregation. PMID:22113733

Salnikova, Maya S; Davis, Harrison; Mensch, Christopher; Celano, Lauren; Thiriot, David S

2012-03-01

183

Particle Sorting by Repeated Freezing and Thawing  

Microsoft Academic Search

If a hetrogeneous mixture of particles of various sizes is frozen and thawed repeatedly, the particles are sorted into relatively uniform groups by size. The movement of particles depends on the amount of water between the ice-water interface and the particle, the rate of freezing, the distribution of the particles by size, and the orientation of the freeze-thaw plane.

Arturo E. Corte

1963-01-01

184

Inherent freeze protection for solar water heaters  

SciTech Connect

Research and development of a method for protection of a solar collector from freezing is described. The method is shown to be technically and economically feasible. A prototype water heating system using the inherent freeze protection method was successfully operated during the winter of 1980 to 1981.

Jeter, S.M.; Leonaitis, L.L.; Leonaitis, L.L.

1981-05-01

185

Recovery of White Blood Cells After Freezing.  

National Technical Information Service (NTIS)

Whereas the red cells recover from the actual congelation of all the water freezable at -3C, the neutrophils are already injured when only a fraction of the water freezable at -1.5C is congealed. Electron microscope studies of freeze-dried or freeze-subsi...

B. J. Luyet L. J. Menz G. L. Rapatz D. Rasmussen

1971-01-01

186

Two simple freeze drying microscope stages  

Microsoft Academic Search

In many instances it is advantageous to make real-time observations of freeze drying phenomena on a microscopic level. Two simple vacuum freeze drying chambers, suitable for use with the optical microscope at higher magnifications (600×), are described and examples of their use are noted.

James M. Flink; Frederik Gejl-Hansen

1978-01-01

187

Can freezing cause floods on Mars?  

Microsoft Academic Search

Floodwaters on Mars likely originated from aquifers confined below a cryosphere. We use an analytical solution to examine freezing-induced pressurization as a mechanism for releasing groundwater. The results suggest that freezing of an aquifer of global extent under the optimal conditions, i.e., perfectly confined and with low compressibility and high permeability relative to the terrestrial analogs, can release enough floodwaters

Chi-yuen Wang; Michael Manga; Jeffrey C. Hanna

2006-01-01

188

Molten Salt Freeze Seal. Final Report.  

National Technical Information Service (NTIS)

This report documents the results of the testing performed at Sandia National Laboratory, Albuquerque, New Mexico, on the applicability of a sodium freeze seal type valve stem in a molten salt environment. The freeze seal tests consisted of cycling the va...

J. J. Corugedo

1985-01-01

189

Colloid-facilitated mobilization of metals by freeze-thaw cycles.  

PubMed

The potential of freeze-thaw cycles to release colloids and colloid-associated contaminants into water is unknown. We examined the effect of freeze-thaw cycles on the mobilization of cesium and strontium in association with colloids in intact cores of a fractured soil, where preferential flow paths are prevalent. Two intact cores were contaminated with cesium and strontium. To mobilize colloids and metal cations sequestered in the soil cores, each core was subjected to 10 intermittent wetting events separated by 66 h pauses. During the first five pauses, the cores were dried at room temperature, and during last five pauses, the cores were subjected to 42 h of freezing followed by 24 h of thawing. In comparison to drying, freeze-thaw cycles created additional preferential flow paths through which colloids, cesium, and strontium were mobilized. The wetting events following freeze-thaw intervals mobilized about twice as many colloids as wetting events following drying at room temperature. Successive wetting events following 66 h of drying mobilized similar amounts of colloids; in contrast, successive wetting events after 66 h of freeze-thaw intervals mobilized greater amounts of colloids than the previous one. Drying and freeze-thaw treatments, respectively, increased and decreased the dissolved cesium and strontium, but both treatments increased the colloidal cesium and strontium. Overall, the freeze-thaw cycles increased the mobilization of metal contaminants primarily in association with colloids through preferential flow paths. These findings suggest that the mobilization of colloid and colloid-associated contaminants could increase when temperature variations occur around the freezing point of water. Thus, climate extremes have the potential to mobilize contaminants that have been sequestered in the vadose zone for decades. PMID:24377325

Mohanty, Sanjay K; Saiers, James E; Ryan, Joseph N

2014-01-21

190

Freezing kinetics in overcompressed water  

NASA Astrophysics Data System (ADS)

The transformation of water into ice is among the most common first order phase transitions occurring in nature, but it is far from being an ordinary one. Water has unusual physical properties both as a liquid and as a solid due largely to hydrogen bonding effects, which also play a major role in determining the characteristics of its freezing kinetics. We report high pressure dynamic compression experiments of liquid water along a quasi-adiabatic path leading to the formation of ice VII. We observe dynamic features resembling Van der Waals loops and find that liquid water is compacted to a metastable state close to the ice density before the onset of crystallization. By analyzing the characteristic kinetic time scale involved we estimate the nucleation barrier and conclude that liquid water has been compressed to a high pressure state close to its thermodynamic stability limit.

Bastea, Marina; Bastea, S.; Reaugh, J.; Reisman, D.

2007-03-01

191

Oocyte freezing: timely reproductive insurance?  

PubMed

Cryopreservation of unfertilised oocytes for later use in initiating pregnancy is now a viable technology, with acceptable pregnancy rates (over 20% per thaw cycle). Oocyte cryopreservation used as a form of insurance against "social" (age-related) infertility can improve the lifetime chance of pregnancy in women who defer pregnancy into their late 30s or early 40s. We report two pregnancies using oocytes that were frozen for social rather than medical reasons, as part of a larger series of nine pregnancies using cryopreserved oocytes. Use of oocytes harvested and frozen from women aged under 35 years may more than double the chance of pregnancy for a 41-year-old woman. The disadvantages of oocyte freezing for social infertility reasons include cost, the usual risks associated with in-vitro fertilisation, and the lack of a guarantee of eventual pregnancy. PMID:19296788

Molloy, David; Hall, Barbara A; Ilbery, Mariannne; Irving, Jacqui; Harrison, Keith L

2009-03-01

192

Depression: What We Know.  

ERIC Educational Resources Information Center

This booklet is concerned with the area of clinical depression. Questions about clinical depression are briefly answered in an overview section and are examined in greater detail in the five chapters that follow. In chapter 1, depression is defined and various types of depression are identified. The origins of depression are explored in the second…

Lobel, Brana; Hirschfeld, Robert M. A.

193

Realization at IMGC of the ITS90 Fixed Points from the Argon Triple Point Upwards  

Microsoft Academic Search

The actual status of IMGC facilities for the realization of the ITS-90 fixed points is illustrated, including new apparatus for the realization of the triple point of argon and of the freezing points of gold and copper. For each fixed point very long phase transitions are obtained, and several thermometers can be calibrated on each plateau. The present apparatus is

P. Marcarino; P. P. M. Steur; R. Dematteis

2003-01-01

194

Nutritional interventions in depression and perinatal depression.  

PubMed

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

Rechenberg, Kaitlyn; Humphries, Debbie

2013-06-01

195

Survey of depression by Beck Depression Inventory in uremic patients undergoing hemodialysis and hemodiafiltration.  

PubMed

High prevalence of depression has been reported in patients with end stage kidney disease and depression is associated with increased morbidity and mortality. We aimed to investigate the prevalence of depression in patients receiving standard hemodialysis (SHD) and hemodiafiltration (HDF) and compare the associated factors between these treatment modalities. The Beck Depression Inventory (BDI) was used to survey for major depressive symptoms. Demographic and biochemical data were reviewed and collected. Point prevalence of depression in HDF patients was significantly lower than SHD patients (23.9% vs. 43.1%, P < 0.05). The BDI score was also higher in SHD than HDF group (13.2 ± 11.6 vs. 8.7 ± 11.2, P < 0.05). SHD patients with major depressive symptoms had significantly lower levels of hemoglobin, albumin, creatinine, sodium and hand grip strength but had higher prevalence of diabetes and high sensitivity C-reactive protein (hs-CRP) levels. In HDF patients, phosphorus level was significantly lower in patients with major depressive symptoms. Logistic regression analysis revealed that hs-CRP, serum sodium and hand grip strength were significantly associated with major depressive symptoms in patients treated with SHD; while serum phosphorus was identified in HDF groups. We concluded that prevalence of depression was high in dialysis patients. Patients receiving HDF had a lower mean BDI score and a nearly 50% lower prevalence rate of major depressive symptoms than that of SHD. Factors associated with depression were different between two modalities. PMID:23190518

Su, Shu-Fen; Ng, Hwee-Yeong; Huang, Tiao-Lai; Chi, Po-Jui; Lee, Yueh-Ting; Lai, Chun-Ren; Lin, Yau-Hsing; Huang, Pei-Chen; Lee, Chien-Te

2012-12-01

196

Tratamento da depressão bipolar The Treatment of Bipolar Depression  

Microsoft Academic Search

The treatment of bipolar depression has been an area of debate. The use of antidepressants, particularly the triciclics, has been associated with worse clinical outcomes. Evidence points to a limited efficacy of traditional mood stabilizers such as lithium, valproate and carbamazepine in the treatment of bipolar depression. In cases where depression is more severe, there is evidence that antidepressants may

BENY LAFER; MARCIA B RITTO; MACEDO SOARES

2005-01-01

197

The GABAergic deficit hypothesis of major depressive disorder  

Microsoft Academic Search

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

B Luscher; Q Shen; N Sahir

2011-01-01

198

Vulnerability for Depression.  

National Technical Information Service (NTIS)

The vulnerability to depression and the antecedents for depression were collected and analyzed for an epidemiological pilot study of depression. Results of one test showed those categorized as 'invulnerables' as having a more positive opinion of their soc...

P. M. Lewinsohn

1980-01-01

199

Depression and Multiple Sclerosis  

MedlinePLUS

... to manage the emotional impact of MS. Treating depression People who are depressed often want to withdraw ... Look So Good" (.pdf) Download Brochure Talk About Depression Provide and receive support, information and advice related ...

200

How Does Depression Develop?  

MedlinePLUS

How Does Depression Develop? How Does Depression Develop? htmHowDepressionDevelops Your genes, hormones and life experiences can all contribute. 362664 InteliHealth 2010-09-27 t InteliHealth/Harvard Medical ...

201

Preclinical Models of Depression.  

National Technical Information Service (NTIS)

New animal models of human depression, especially endogenous depression, were developed. Depression was induced by means other than drugs. The model was validated by behavioral, neuroendocrine and neurochemical resemblances to the human disorder and by re...

B. J. Carroll

1983-01-01

202

Alcoholism & depression.  

PubMed

One out of 2 Americans report drinking on a routine basis, making the excessive consumption of alcohol the third leading cause of preventable death in America (). Alcoholism and depression are common comorbidities that home healthcare professionals frequently encounter. To achieve the best patient outcomes, alcoholism should be addressed initially. Although all age groups are at risk, alcoholism and depression occur in more than 8 percent of older adults. Prevention through identifying alcohol use early in adolescence is vital to reduce the likelihood of alcohol dependence. This article provides an overview of the long-term effects of alcohol abuse, including alcoholic cirrhosis and hepatic encephalopathy. The diagnostic criteria for substance dependence and ideas for nonthreatening screening questions to use with patients who are adolescent or older are discussed. While providing patient care, home healthcare nurses share the patient's intimate home environment. This environment is perceived as a safe haven by the patient and home care nurses can take advantage of counseling and treatment opportunities in this nonthreatening environment. PMID:23026991

Hall, Mellisa

2012-10-01

203

New particle dependant parameterizations of heterogeneous freezing processes.  

NASA Astrophysics Data System (ADS)

For detailed investigations of cloud microphysical processes an adiabatic air parcel model with entrainment is used. It represents a spectral bin model which explicitly solves the microphysical equations. The initiation of the ice phase is parameterized and describes the effects of different types of ice nuclei (mineral dust, soot, biological particles) in immersion, contact, and deposition modes. As part of the research group INUIT (Ice Nuclei research UnIT), existing parameterizations have been modified for the present studies and new parameterizations have been developed mainly on the basis of the outcome of INUIT experiments. Deposition freezing in the model is dependant on the presence of dry particles and on ice supersaturation. The description of contact freezing combines the collision kernel of dry particles with the fraction of frozen drops as function of temperature and particle size. A new parameterization of immersion freezing has been coupled to the mass of insoluble particles contained in the drops using measured numbers of ice active sites per unit mass. Sensitivity studies have been performed with a convective temperature and dew point profile and with two dry aerosol particle number size distributions. Single and coupled freezing processes are studied with different types of ice nuclei (e.g., bacteria, illite, kaolinite, feldspar). The strength of convection is varied so that the simulated cloud reaches different levels of temperature. As a parameter to evaluate the results the ice water fraction is selected which is defined as the relation of the ice water content to the total water content. Ice water fractions between 0.1 and 0.9 represent mixed-phase clouds, larger than 0.9 ice clouds. The results indicate the sensitive parameters for the formation of mixed-phase and ice clouds are: 1. broad particle number size distribution with high number of small particles, 2. temperatures below -25°C, 3. specific mineral dust particles as ice nuclei such as illite or montmorillonite. Coupled cases of deposition and contact freezing show that they are hardly in competition because of differences in the preferred particle sizes. In the contact mode, small particles are less efficient for collisions as well as less efficient as ice nuclei so that these are available for deposition freezing. On the other hand, immersion freezing is the dominant process when it is coupled with deposition freezing. As it is initiated earlier the formed ice particles consume water vapor for growing. The competition of combined contact and immersion freezing leads to lower ice water contents because more ice particles are formed via the immersion mode. In general, ice clouds and mixed-phase clouds with high ice water fractions are not directly the result of primary ice formation but of secondary ice formation and growth of ice particles at the expense of liquid drops.

Diehl, Karoline; Mitra, Subir K.

2014-05-01

204

Exploring the Nature of Contact Freezing  

NASA Astrophysics Data System (ADS)

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.

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

2012-12-01

205

Chilled water coil freeze protection via internal drying  

SciTech Connect

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.

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

1997-12-01

206

Freeze Denaturation of Fish Muscle Proteins  

NASA Astrophysics Data System (ADS)

Studies on the freeze denaturation of fish muscle proteins were reviewed with emphasis given to changes in their physicochemical and biochemical properties during frozen storage. Denaturation of actomyosin commonly occurs during frozen storage and side-to-side aggregation of myosin molecules apppears to major role in this reaction. The author's group performed freezing studies with isolated preparations of proteins from carp muscle, namely actomyosin, myosin, H-meromyosin, L-meromyosin, and actin. Freeze denaturation occurred with indvidual proteins as well as with their subunits. Not only aggregation but also some conformational changes were observed. Denaturation was inhibited in the presence of added glutamate.

Tsuchiya, Takahide

207

Molten salt freeze seal. Final report  

SciTech Connect

This report documents the results of the testing performed at Sandia National Laboratory, Albuquerque, New Mexico, on the applicability of a sodium freeze seal type valve stem in a molten salt environment. The freeze seal tests consisted of cycling the valve stem at set temperature intervals, checking the temperature distribution for freeze plug location, and verifying the actuator forces. In addition to the test results, this report also documents the engineering analysis and other tasks performed before testing to form a basis for predicted test conditions and recommendations for the test program.

Corugedo, J.J.

1985-08-01

208

Anhedonia, Depressed Mood, and Smoking Cessation Outcome  

PubMed Central

Objective Although the relation between lifetime depression and smoking cessation outcome has been well-studied, the proposition that different symptomatic expressions of depression exert disparate predictive effects on risk of smoking cessation failure has largely gone uninvestigated. This study analyzed the individual contributions of depression's two hallmark affective symptoms, anhedonia (i.e., diminished interest in normally enjoyable activities) and depressed mood (i.e., elevated sadness), to the prediction of smoking cessation outcome. Method Participants were adult daily smokers (N=1469; Mean age = 45 years, 58% Female, 84% White) enrolled in a smoking cessation treatment study. Lifetime history of anhedonia and depressed mood were classified via structured interview prior to quit day. Seven-day point prevalence smoking abstinence was assessed at 8-weeks and 6-months post-quit. Results When examined separately, both lifetime anhedonia, OR(95% CI)=1.42(1.16-1.73), p=.004, and depressed mood, OR(95% CI)=1.35(1.11-1.63), p=.002, predicted increased odds of relapse. These relations remained after adjusting for covariates, including lifetime depressive disorder, which did not predict outcome. After controlling for the covariation between lifetime anhedonia and depressed mood, anhedonia predicted cessation outcome, OR(95% CI)=1.31(1.05-1.62), p=.02, while depressed mood did not, p=.19. Symptom duration (>2 weeks), treatment, and substance use disorder did not modify relations of lifetime anhedonia and depressed mood with cessation outcome. Conclusions Results suggest that: (1) symptoms of affective disturbance capture depression-relevant risk of cessation failure, which is not adequately demarcated by the lifetime depressive disorder diagnosis; and (2) anhedonia is a more sensitive index of this affective disturbance than depressed mood per se. Clinical attention to anhedonia may facilitate smoking cessation.

Leventhal, Adam M.; Piper, Megan E.; Japuntich, Sandra J.; Baker, Timothy B.; Cook, Jessica W.

2014-01-01

209

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

PubMed Central

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.

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

2014-01-01

210

Use of manometric temperature measurement (MTM) and SMART freeze dryer technology for development of an optimized freeze-drying cycle.  

PubMed

This report provides, for the first time, a summary of experiments using SMART Freeze Dryer technology during a 9 month testing period. A minimum ice sublimation area of about 300 cm(2) for the laboratory freeze dryer, with a chamber volume 107.5 L, was found consistent with data obtained during previous experiments with a smaller freeze dryer (52 L). Good reproducibility was found for cycle design with different type of excipients, formulations, and vials used. SMART primary drying end point estimates were accurate in the majority of the experiments, but showed an over prediction of primary cycle time when the product did not fully achieve steady state conditions before the first MTM measurement was performed. Product resistance data for 5% sucrose mixtures at varying fill depths were very reproducible. Product temperature determined by SMART was typically in good agreement with thermocouple data through about 50% of primary drying time, with significant deviations occurring near the end of primary drying, as expected, but showing a bias much earlier in primary drying for high solid content formulations (16.6% Pfizer product) and polyvinylpyrrolidone (40 kDa) likely due to water "re-adsorption" by the amorphous product during the MTM test. PMID:17853427

Gieseler, Henning; Kramer, Tony; Pikal, Michael J

2007-12-01

211

Depressive Symptoms After CABG Surgery: A Meta-analysis  

PubMed Central

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.

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

2013-01-01

212

Automated Assessment of Pavlovian Conditioned Freezing and Shock Reactivity in Mice Using the Video Freeze System  

PubMed Central

The Pavlovian conditioned freezing paradigm has become a prominent mouse and rat model of learning and memory, as well as of pathological fear. Due to its efficiency, reproducibility and well-defined neurobiology, the paradigm has become widely adopted in large-scale genetic and pharmacological screens. However, one major shortcoming of the use of freezing behavior has been that it has required the use of tedious hand scoring, or a variety of proprietary automated methods that are often poorly validated or difficult to obtain and implement. Here we report an extensive validation of the Video Freeze system in mice, a “turn-key” all-inclusive system for fear conditioning in small animals. Using digital video and near-infrared lighting, the system achieved outstanding performance in scoring both freezing and movement. Given the large-scale adoption of the conditioned freezing paradigm, we encourage similar validation of other automated systems for scoring freezing, or other behaviors.

Anagnostaras, Stephan G.; Wood, Suzanne C.; Shuman, Tristan; Cai, Denise J.; LeDuc, Arthur D.; Zurn, Karl R.; Zurn, J. Brooks; Sage, Jennifer R.; Herrera, Gerald M.

2009-01-01

213

Trehalose levels and survival ratio of freeze-tolerant versus freeze-sensitive yeasts.  

PubMed Central

Five freeze-tolerant yeast strains suitable for frozen dough were compared with ordinary commercial bakers' yeast. Kluyveromyces thermotolerans FRI 501 cells showed high survival ability after freezing when their resting cells were fermented for 0 to 180 min in modified liquid medium, and they grew to log and stationary phases. Among the freeze-tolerant strains of Saccharomyces cerevisiae, FRI 413 and FRI 869 showed higher surviving and trehalose-accumulating abilities than other S. cerevisiae strains, but were affected by a prolonged prefermentation period and by growth phases. The freeze tolerance of the yeasts was, to some extent, associated with the basal amount of intracellular trehalose after rapid degradation at the onset of the prefermentation period. In the freeze-sensitive yeasts, the degree of hydrolysis of trehalose may thus be affected by the kind of saccharide, unlike in freeze-tolerant yeasts.

Hino, A; Mihara, K; Nakashima, K; Takano, H

1990-01-01

214

Postpartum depression  

PubMed Central

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.

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

2014-01-01

215

Gullied Depression  

NASA Technical Reports Server (NTRS)

26 February 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows gullies formed in the wall of a depression located on the floor of Rabe Crater west of the giant impact basin, Hellas Planitia. Gullies such as these are common features on Mars, but the process by which they are formed is not fully understood. The debate centers on the role and source of fluids in the genesis of these features.

Location near: 44.1oS, 325.9oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

2006-01-01

216

Clinimetrics of freezing of gait.  

PubMed

The clinical assessment of freezing of gait (FOG) provides great challenges. Patients often do not realize what FOG really is. Assessing FOG is further complicated by the episodic, unpredictable, and variable presentation, as well as the complex relationship with medication. Here, we provide some practical recommendations for a standardized clinical approach. During history taking, presence of FOG is best ascertained by asking about the characteristic feeling of "being glued to the floor." Detection of FOG is greatly facilitated by demonstrating what FOG actually looks like, not only to the patient but also to the spouse or other carer. History taking further focuses on the specific circumstances that provoke FOG and on its severity, preferably using standardized questionnaires. Physical examination should be done both during the ON and OFF state, to judge the influence of treatment. Evaluation includes a dedicated "gait trajectory" that features specific triggers to elicit FOG (gait initiation; a narrow passage; dual tasking; and rapid 360 degrees axial turns in both directions). Evaluating the response to external cues has diagnostic importance, and helps to determine possible therapeutic interventions. Because of the tight interplay between FOG and mental functions, the evaluation must include cognitive testing (mainly frontal executive functions) and judgment of mood. Neuroimaging is required for most patients in order to detect underlying pathology, in particular lesions of the frontal lobe or their connections to the basal ganglia. Various quantitative gait assessments have been proposed, but these methods have not proven value for clinical practice. PMID:18668628

Snijders, Anke H; Nijkrake, Maarten J; Bakker, Maaike; Munneke, Marten; Wind, Carina; Bloem, Bastiaan R

2008-01-01

217

Threshold temperatures mediate the impact of reduced snow cover on overwintering freeze-tolerant caterpillars  

NASA Astrophysics Data System (ADS)

Decreases in snow cover due to climate change could alter the energetics and physiology of ectothermic animals that overwinter beneath snow, yet how snow cover interacts with physiological thresholds is unknown. We applied numerical simulation of overwintering metabolic rates coupled with field validation to determine the importance of snow cover and freezing to the overwintering lipid consumption of the freeze-tolerant Arctiid caterpillar Pyrrharctia isabella. Caterpillars that overwintered above the snow experienced mean temperatures 1.3°C lower than those below snow and consumed 18.36 mg less lipid of a total 68.97-mg reserve. Simulations showed that linear temperature effects on metabolic rate accounted for only 30% of the difference in lipid consumption. When metabolic suppression by freezing was included, 93% of the difference between animals that overwintered above and below snow was explained. Our results were robust to differences in temperature sensitivity of metabolic rate, changes in freezing point, and the magnitude of metabolic suppression by freezing. The majority of the energy savings was caused by the non-continuous reduction in metabolic rate due to freezing, the first example of the importance of temperature thresholds in the lipid use of overwintering insects.

Marshall, Katie E.; Sinclair, Brent J.

2012-01-01

218

Depression in Children and Teens  

MedlinePLUS

... Return to Web version Depression in Children and Teens Depression in Children and Teens How are the symptoms ... might mean your child is depressed. Why do young people get depressed? Many things can cause depression, ...

219

A Generalized Correlation for Heat and Mass Transfer in Freezing, Drying, Frying, and Freeze Drying  

Microsoft Academic Search

Experiments on air freezing, deep frying, freeze drying, and air drying on similar samples of 12 mm slice of potato were carried out. The temperature change with time was measured at three locations across the thickness of the potato. All the measurements done on frying, freeze-drying, and air-drying showed the existence of a moving interface that recedes towards the center of

Mohammed Farid; Sally Butcher

2003-01-01

220

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

Microsoft Academic Search

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

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

2010-01-01

221

Viability of mass algal cultures preserved by freezing and freeze-drying  

Microsoft Academic Search

The microalgae Chaetoceros sp. and Phaeodactylum tricornutum were grown in semicontinuous 15 1 cultures, a volume commonly used for mid-scale inocula in aquacultural practices. The daily yields were concentrated and stored by freezing and freeze-drying for up to 1 month. After slow or fast freezing without the protective agents glycerol or Me2SO, neither of the microalgae was capable of active

Beatriz Cordero; Domenico Voltolina

1997-01-01

222

Steam Consumption Reduction by Eutectic Freeze Crystallization.  

National Technical Information Service (NTIS)

Steam production in American beet sugar factories can be reduced by 600 pounds per ton of beets by using hydrate freeze crystallization in place of pan evaporators for sugar crystallization. This is a relatively constant number, regardless of current fact...

S. E. Bichsel M. Cleary T. S. Barron J. A. Heist

1985-01-01

223

Cell-encapsulating droplet formation and freezing  

NASA Astrophysics Data System (ADS)

Cell-encapsulating droplets are vitrified for biopreservation applications. The dynamics of micro-droplet formation and its freezing mechanism are analyzed numerically and experimentally. In addition, the microdroplet encapsulation technique is applied to cryopreserve cells.

Ryoun Youn, Jae; Seok Song, Young

2012-09-01

224

Energies of freezing and frost desiccation.  

PubMed

A stable cellulose paper system was studied to relate water distribution data, as obtained previously from plant tissues, to the analysis of freezing energy. Water distribution data for the cellulose system were obtained by several techniques and were coordinated with calorimetric data. The effect of the cellulose system on the latent heat of freezing was evaluated to estimate activation energies as functions of the amount of associated liquid water. Similar activation energies of water phase transitions in critical plant tissue systems may be heritable characteristics that affect freezing stress. Adhesion energy, that develops between ice and hydrophilic polymer systems as they compete for liquid water in a complex interface, was suggested as one possible source of freezing stress. This does not occur in frost desiccation. PMID:16658785

Olien, C R

1974-05-01

225

Role of growth phase and ethanol in freeze-thaw stress resistance of Saccharomyces cerevisiae.  

PubMed

The freeze-thaw tolerance of Saccharomyces cerevisiae was examined throughout growth in aerobic batch culture. Minimum tolerance to rapid freezing (immersion in liquid nitrogen; cooling rate, approximately 200 degrees C min-1) was associated with respirofermentative (exponential) growth on glucose. However, maximum tolerance occurred not during the stationary phase but during active respiratory growth on ethanol accumulated during respirofermentative growth on glucose. The peak in tolerance occurred several hours after entry into the respiratory growth phase and did not correspond to a transient accumulation of trehalose which occurred at the point of glucose exhaustion. Substitution of ethanol with other carbon sources which permit high levels of respiration (acetate and galactose) also induced high freeze-thaw tolerance, and the peak did not occur in cells shifted directly from fermentative growth to starvation conditions or in two respiratorily incompetent mutants. These results imply a direct link with respiration, rather than exhaustion of glucose. The role of ethanol as a cryoprotectant per se was also investigated, and under conditions of rapid freezing (cooling rate, approximately 200 degrees C min-1), ethanol demonstrated a significant cryoprotective effect. Under the same freezing conditions, glycerol had little effect at high concentrations and acted as a cryosensitizer at low concentrations. Conversely, under slow-freezing conditions (step freezing at -20, -70, and then -196 degrees C; initial cooling rate, approximately 3 degrees C min-1), glycerol acted as a cryoprotectant while ethanol lost this ability. Ethanol may thus have two effects on the cryotolerance of baker's yeast, as a respirable carbon source and as a cryoprotectant under rapid-freezing conditions. PMID:8476282

Lewis, J G; Learmonth, R P; Watson, K

1993-04-01

226

Role of growth phase and ethanol in freeze-thaw stress resistance of Saccharomyces cerevisiae.  

PubMed Central

The freeze-thaw tolerance of Saccharomyces cerevisiae was examined throughout growth in aerobic batch culture. Minimum tolerance to rapid freezing (immersion in liquid nitrogen; cooling rate, approximately 200 degrees C min-1) was associated with respirofermentative (exponential) growth on glucose. However, maximum tolerance occurred not during the stationary phase but during active respiratory growth on ethanol accumulated during respirofermentative growth on glucose. The peak in tolerance occurred several hours after entry into the respiratory growth phase and did not correspond to a transient accumulation of trehalose which occurred at the point of glucose exhaustion. Substitution of ethanol with other carbon sources which permit high levels of respiration (acetate and galactose) also induced high freeze-thaw tolerance, and the peak did not occur in cells shifted directly from fermentative growth to starvation conditions or in two respiratorily incompetent mutants. These results imply a direct link with respiration, rather than exhaustion of glucose. The role of ethanol as a cryoprotectant per se was also investigated, and under conditions of rapid freezing (cooling rate, approximately 200 degrees C min-1), ethanol demonstrated a significant cryoprotective effect. Under the same freezing conditions, glycerol had little effect at high concentrations and acted as a cryosensitizer at low concentrations. Conversely, under slow-freezing conditions (step freezing at -20, -70, and then -196 degrees C; initial cooling rate, approximately 3 degrees C min-1), glycerol acted as a cryoprotectant while ethanol lost this ability. Ethanol may thus have two effects on the cryotolerance of baker's yeast, as a respirable carbon source and as a cryoprotectant under rapid-freezing conditions.

Lewis, J G; Learmonth, R P; Watson, K

1993-01-01

227

Composition and freezing of aqueous H2SO4/HNO3 solutions under polar stratospheric conditions  

NASA Technical Reports Server (NTRS)

The results of laboratory investigations of the freezing behavior of aqueous acid solutions indicate that in the stratosphere H2SO/H2O aerosol droplets would not freeze at temperatures above the ice frost point in the absence of HNO3; however, in the presence of typical levels of HNO3 liquid sulfuric acid aerosols take up significant amounts of HNO3 and H2O vapors and freeze much more readily. This is a consequence of the very rapid change in composition of the liquid droplets as the temperature drops to within two to three degrees of the equilibrium temperature at which HNO3 and H2O vapors would co-condense to form a liquid solution. In the high latitude stratosphere this HNO3/H2O 'dew point' is typically around 192-194 K at 100 mbar.

Beyer, K. D.; Seago, S. W.; Chang, H. Y.; Molina, M. J.

1994-01-01

228

Passive freeze protection for solar collectors  

Microsoft Academic Search

Freeze damage is an important practical problem for water-type solar collectors. In the past, electric resistance heaters, drain systems, and separate ethylene glycol-water collection loops have commonly been used to prevent freezing. These techniques are effective but involve active components such as controls, heaters, valves, solenoids, pumps, heat exchangers, etc., that increase costs, degrade reliability and\\/or reduce overall efficiency. This

L. W. Bickle

1975-01-01

229

Freezing Characteristics of Rigid Plant Tissues (Development of Cell Tension during Extracellular Freezing).  

PubMed Central

The freezing characteristics and development of cell tension during extracellular freezing were examined in supercooling stem tissues of riverbank grapes (Vitis riparia) and cold-hardened leaves of live oak (Quercus virginiana) and mountain cranberry (Vaccinium vitis-idaea). Dormant stem xylem and pith tissues of river-bank grapes were resistant to freeze-induced dehydration above the homogeneous nucleation temperature, and they developed cell tension reaching a maximum of 27 MPa. Similarly, extracellular freezing induced cell tension in the leaves of live oak and mountain cranberry. Maximum cell tension in the leaves of live oak was 16.8 MPa and 8.3 MPa in the leaves of mountain cranberry. Following peak tensions in the leaves, a decline in the pressure was observed with progressive freezing. The results suggest that resistance to cell deformation during extracellular freezing due to cell-wall rigidity can lead to reduced cell dehydration and increased cell tension. A relationship to predict freezing behavior in plant tissues based on cell rigidity is presented. Based on cell-water relations and ice nucleation rates, cell-wall rigidity has been shown to effect the freezing characteristics of plant tissues, including freeze-induced dehydration, supercooling, and homogeneous nucleation temperatures.

Rajashekar, C. B.; Burke, M. J.

1996-01-01

230

Freeze Drying of Foods for the Armed Services.  

National Technical Information Service (NTIS)

The report reviews the development and use of freeze-dried food products for the Armed Services. It covers the various products and ration systems that have been developed, the basic parameters of freeze-drying and freeze-dried foods, commercial freeze-dr...

J. M. Tuomy

1971-01-01

231

Simulation and application of GPR in Artificial Freezing Engineering  

Microsoft Academic Search

In Artificial Freezing Engineering(AFE), the distribution of freezing soil and its defects are important to engineering safety. Based on relative permittivity measured by vector network analyzer, electromagnetic models of artificial freezing walls were made. Then Ground Penetrating Radar (GPR) exploration of AFE was simulated by Time Domain Finite Element Method (TD-FEM) coupled with freezing temperature calculation. GPR were also used

Song Lei; Zhang Xiaojun; Li Haipeng; Zhang Houquan

2010-01-01

232

Baseline Reaction Time Predicts 12Month Smoking Cessation Outcome in Formerly Depressed Smokers  

Microsoft Academic Search

Burgeoning evidence points to a positive association between cigarette smoking and depression. Moreover, depressive symptomatology, whether historical, current, or subsyndromal, appears to negatively influence smoking cessation efforts. Whereas depression is typically assessed via clinical interview or self-report, rarely are the known neurocognitive deficits linked to depression (e.g., global slowing) assessed in the context of smoking cessation research. Hence, this study

Jon D. Kassel; Marisa Yates; Richard A. Brown

2007-01-01

233

Spacecraft Radiator Freeze Protection Using a Regenerative Heat Exchanger with Bypass Setpoint Temperature Control  

NASA Technical Reports Server (NTRS)

Spacecraft radiators are sized for their maximum heat load in their warmest thermal environment, but must operate at reduced heat loads and in colder environments. For systems where the radiator environment can be colder than the working fluid freezing temperature, radiator freezing becomes an issue. Radiator freezing has not been a major issue for the Space Shuttle and the International Space Station (ISS) active thermal control systems (ATCSs) because they operate in environments that are warm relative to the freezing point of their external coolants (Freon-21 and ammonia, respectively). For a vehicle that lands at the Lunar South Pole, the design thermal environment is 215K, but the radiator working fluid must also be kept from freezing during the 0 K sink of transit. A radiator bypass flow control design such as those used on the Space Shuttle and ISS requires more than 30% of the design heat load to avoid radiator freezing during transit - even with a very low freezing point working fluid. By changing the traditional ATCS architecture to include a regenerating heat exchanger inboard of the radiator and by using a regenerator bypass flow control valve to maintain system setpoint, the required minimum heat load can be reduced by more than half. This gives the spacecraft much more flexibility in design and operation. The present work describes the regenerator bypass ATCS setpoint control methodology. It includes analytical results comparing the performance of this system to the traditional radiator bypass system. Finally, a summary of the advantages of the regenerator bypass system are presented.

Ungar, Eugene K.

2008-01-01

234

The Great Depression  

NSDL National Science Digital Library

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. ...

Randyandamber

2007-11-30

235

Depression and pancreatic cancer  

Microsoft Academic Search

Although pancreatic carcinoma and depression have been linked for years, the prevalence and relationship of these often coexisting diseases are still poorly understood. A clinical gestalt asserts that many patients present with depression before pancreatic carcinoma is diagnosed. Published studies reviewing this issue have found that many patients with pancreatic cancer are depressed. If the definition of depression is broadened

A. D. Boyd; M. Riba

2007-01-01

236

Depression at adolescence  

Microsoft Academic Search

BACKGROUND Mental disorders affect young people disproportionately and are increasing in prevalence. Knowledge about depression in adolescents and skill in its management lags behind that for adults. Depression is the most common mental disorder and untreated depression is associated with significant adverse effects. Depression is also a major predictor of suicidal behaviour and suicide. The role of the general practitioner

N. Zdanowicz; E. Coremans; C. Reynaert; Mark Stemmler; Sydney Ey; Kathryn E. Grant

2002-01-01

237

Embodiment, mindfulness, and depression  

Microsoft Academic Search

In this paper we will present results of a series of studies investigating the embodiment of depression. The first series of studies analyzed gait patterns in depression. Using a motion capture system we investigated (1) whether dynamic gait patterns of currently and formerly depressed patients differ from never depressed people and (2) whether mindfulness-based cognitive therapy (MBCT) normalize gait patterns

J. Michalak; J. Burg; T. Heidenreich; N. F. Troje

2011-01-01

238

Childhood and Adolescent Depression  

Microsoft Academic Search

Major depression affects 3 to 5 percent of children and adolescents. Depression negatively impacts growth and devel- opment, school performance, and peer or family relationships and may lead to suicide. Biomedical and psychosocial risk factors include a family history of depression, female sex, childhood abuse or neglect, stressful life events, and chronic illness. Diagnostic criteria for depression in children and

SHASHI K. BHATIA; SUBHASH C. BHATIA

2007-01-01

239

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

PubMed

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

Wang, Yuan-Pang; Gorenstein, Clarice

2013-09-01

240

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

PubMed Central

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.

Wang, Yuan-Pang; Gorenstein, Clarice

2013-01-01

241

A new freeze casting technique for ceramics  

NASA Astrophysics Data System (ADS)

A new freeze casting technique for ceramics capable of manufacturing near room temperature with a sublimable vehicle has been developed in order to eliminate expensive processes under extremely cold temperatures in the conventional freeze casting. Fluid concentrated slurries of Al2O 3 powder in molten camphene (C10H16) were successfully prepared at 55°C with a small amount of a dispersant. These slurries were quickly solidified (frozen) at room temperature to yield a rigid solid green body, where the frozen camphene was easily removed by sublimation (freeze-drying) with negligible shrinkage. Sintering was successfully conducted without any special binder burnout process to yield dense sintered bodies (over 98% T.D). An organic alloy with a eutectic composition in the naphthalene (C 10H8)-camphor (C10H16O) binary system with a eutectic temperature of 31°C was also found to be a successful vehicle for the new ceramic freeze casting. The fabrication processes are almost the same as those with camphene. It was found that vehicles with off-eutectic compositions resulted in large voids in the sintered body due to the ceramic particle rejection by pro-eutectic crystals during freezing. At the eutectic composition, fine lamellar microstructure in the solidified vehicle inhibits the particle rejection. The proposed advantages of the new freeze casting technique with a sublimable vehicle include; (1) elimination of extremely cold temperatures used in conventional freeze casting; (2) elimination of troublesome binder burnout process; and (3) fast manufacturing cycle due to quick solidification. Porous ceramic bodies with unique interconnected pore channels were fabricated by the new freeze casting with lower solid content. The unique channels surrounded by fully dense walls have nearly circular cross-sections unlike conventional aqueous freeze casting. The porosity and the channel diameters are controllable by the solid content in the slurry. The unique channels are replicas of entangled dendrites of frozen camphene, which sublimes during freeze-drying process. The unique porous structure with interconnected pore channels, which is completely new, is considered potentially useful in many applications such as filters and implantable bone scaffolds.

Araki, Kiyoshi

242

An approach to managing depression Defining and measuring outcomes  

Microsoft Academic Search

OBJECTIVE To provide family physicians with a contemporary approach to formulating a treatment model for major depressive disorder that integrates definitions of new therapeutic end points, familiarizes them with tools for assessing these end points, and describes newer methods for enhancing outcome. SOURCES OF INFORMATION Canadian Psychiatric Association Guidelines for the Treatment of Depressive Disorders, relevant articles from a MEDLINE

Atul Khullar; Roger S. McIntyre

243

Intercomparing the Freezing Behaviour of Silver Cells of the NRC and the ITRI  

NASA Astrophysics Data System (ADS)

Equilibrium freezing points of four silver ingots were intercompared. A spread of values of about 18 mK was found between the, presumably, purest and the most impure sample. The influence of furnace temperature upon the plateau temperature, via non-equilibrium effects at the solid-liquid interface, is discussed.

Ancsin, J.; Yeh, T. I.; Lin, J.; Chu, Yung-Hsiang

1993-01-01

244

Predicting Arabidopsis Freezing Tolerance and Heterosis in Freezing Tolerance from Metabolite Composition  

PubMed Central

Heterosis, or hybrid vigor, is one of the most important tools in plant breeding and has previously been demonstrated for plant freezing tolerance. Freezing tolerance is an important trait because it can limit the geographical distribution of plants and their agricultural yield. Plants from temperate climates increase in freezing tolerance during exposure to low, non-freezing temperatures in a process termed ‘cold acclimation’. Metabolite profiling has indicated a major reprogramming of plant metabolism in the cold, but it has remained unclear in previous studies which of these changes are related to freezing tolerance. In the present study, we have used metabolic profiling to discover combinations of metabolites that predict freezing tolerance and its heterosis in Arabidopsis thaliana. We identified compatible solutes and, in particular, the pathway leading to raffinose as crucial statistical predictors for freezing tolerance and its heterosis, while some TCA cycle intermediates contribute only to predicting the heterotic phenotype. This indicates coordinate links between heterosis and metabolic pathways, suggesting that a limited number of regulatory genes may determine the extent of heterosis in this complex trait. In addition, several unidentified metabolites strongly contributed to the prediction of both freezing tolerance and its heterosis and we present an exemplary analysis of one of these, identifying it as a hexose conjugate.

Korn, Marina; Gartner, Tanja; Erban, Alexander; Kopka, Joachim; Selbig, Joachim; Hincha, Dirk K.

2010-01-01

245

Freezing and Freeze-Drying of Serratia Marcescens Suspended in Sodium Chloride.  

National Technical Information Service (NTIS)

Studies were made of the effects of NaCl upon the survival of Serratia marcescens after freezedrying or freeze-thawing. Freeze-dried cells showed lowest survival in the presence of 5% NaCl; higher and lower concentrations yielded higher recovery levels. C...

L. Zimmerman

1964-01-01

246

Investigations on Freezing and Freeze-Drying of Selected Fruits and Vegetables.  

National Technical Information Service (NTIS)

Investigations were made on the mode of invasion of fruit and vegetable tissue by ice and the changes produced by freezing and thawing and freeze-drying of the tissues as well as rehydration evaluations. In general three methods of exploring the effects o...

B. J. Luyet

1968-01-01

247

Resistance to freezing and freeze-drying storage processes of potential probiotic bifidobacteria  

Microsoft Academic Search

The resistance to freezing at -135 °C and freeze-drying of potentially probiot- ic bifidobacteria strains isolated from human habitat and from commercial probiotic prod- ucts already present in the Italian market were tested. The analysis was conducted in two different cryoprotectives, sucrose and skim milk. The strains of Bifidobacterium animalis, the only species found in the commercial probiotic product, were

M. MODESTO; P. MATTARELLI; B. BIAVATI

2004-01-01

248

Associations among smoking, anhedonia, and reward learning in depression.  

PubMed

Depression and cigarette smoking co-occur at high rates. However, the etiological mechanisms that contribute to this relationship remain unclear. Anhedonia and associated impairments in reward learning are key features of depression, which also have been linked to the onset and maintenance of cigarette smoking. However, few studies have investigated differences in anhedonia and reward learning among depressed smokers and depressed nonsmokers. The goal of this study was to examine putative differences in anhedonia and reward learning in depressed smokers (n=36) and depressed nonsmokers (n=44). To this end, participants completed self-report measures of anhedonia and behavioral activation (BAS reward responsiveness scores) and as well as a probabilistic reward task rooted in signal detection theory, which measures reward learning (Pizzagalli, Jahn, & O'Shea, 2005). When considering self-report measures, depressed smokers reported higher trait anhedonia and reduced BAS reward responsiveness scores compared to depressed nonsmokers. In contrast to self-report measures, nicotine-satiated depressed smokers demonstrated greater acquisition of reward-based learning compared to depressed nonsmokers as indexed by the probabilistic reward task. Findings may point to a potential mechanism underlying the frequent co-occurrence of smoking and depression. These results highlight the importance of continued investigation of the role of anhedonia and reward system functioning in the co-occurrence of depression and nicotine abuse. Results also may support the use of treatments targeting reward learning (e.g., behavioral activation) to enhance smoking cessation among individuals with depression. PMID:25022776

Liverant, Gabrielle I; Sloan, Denise M; Pizzagalli, Diego A; Harte, Christopher B; Kamholz, Barbara W; Rosebrock, Laina E; Cohen, Andrew L; Fava, Maurizio; Kaplan, Gary B

2014-09-01

249

Freeze thaw cycles in Toronto, Canada in a changing climate  

NASA Astrophysics Data System (ADS)

Freeze thaw cycles are examined in Toronto Canada. Using data from 1960 to 1989 for three Toronto area weather stations, trends in freeze thaw activity, the relationship to mean monthly temperature and projections of freeze thaw activity are examined. For downtown Toronto the annual frequency of freeze thaw cycles is decreasing significantly, most notably in the shoulder months of October and April. At the Pearson International Airport and the Toronto Island Airport similar annual trends were not found, however there was evidence of decreased freeze thaw activity in April and October. Polynomial curve fitting provided functional relationships between mean monthly temperature and freeze thaw activity. These relationships enabled the assessment of freeze thaw activity under synthetic warming conditions. The results of this analysis show that the warming of the magnitude typically projected for the rest of this century will not likely generate a significant change in the freeze thaw activity although there are indications that the freeze thaw season will contract.

Ho, E.; Gough, W. A.

2006-01-01

250

Freeze drying for morphological control of inter-penetrating polymer networks  

NASA Technical Reports Server (NTRS)

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.

Hansen, Marion G.; Pater, Ruth H.

1990-01-01

251

Depression and the heart  

PubMed Central

Cardio Vascular disease (CVD) as well as depression are both highly prevalent disorders and both of them cause a significant decrease in quality of life and increase the economic burden for the patient. Depressed individuals are more likely to develop angina, fatal or non-fatal myocardial infarction, than those who are not depressed. Over the past decade, evidence has accumulated to suggest that depression may be a risk factor for cardiac mortality in patients with established coronary artery disease (CAD). The ‘vicious cycle’ linking CVD to major depression and depression to CVD, deserves greater attention from both cardio-vascular and psychiatric investigators.1

Saran, R.K.; Puri, Aniket; Agarwal, Manu

2012-01-01

252

Heat transfer coefficient of cryotop during freezing.  

PubMed

Cryotop is an efficient vitrification method for cryopreservation of oocytes. It has been widely used owing to its simple operation and high freezing rate. Recently, the heat transfer performance of cryotop was studied by numerical simulation in several studies. However, the range of heat transfer coefficient in the simulation is uncertain. In this study, the heat transfer coefficient for cryotop during freezing process was analyzed. The cooling rates of 40 percent ethylene glycol (EG) droplet in cryotop during freezing were measured by ultra-fast measurement system and calculated by numerical simulation at different value of heat transfer coefficient. Compared with the results obtained by two methods, the range of the heat transfer coefficient necessary for the numerical simulation of cryotop was determined, which is between 9000 W/(m(2)·K) and 10000 W/(m (2)·K). PMID:23812315

Li, W J; Zhou, X L; Wang, H S; Liu, B L; Dai, J J

2013-01-01

253

Estimation of short musical fragments in normal subjects and patients with chronic depression  

Microsoft Academic Search

Emotional estimation of short fragments of classical music was analyzed in healthy subjects and patients with depressive neurosis\\u000a and retarded depression (the depressive phase of maniac-depressive psychosis). The values and stability of point estimates\\u000a varied between the studied groups. Narrowing of the range of emotional estimates was found in depressed patients. Standard\\u000a deviation of estimates was related to musical key

Ya. A. Al’tman; Yu. O. Alyanchikova; B. M. Guzikov; L. E. Zakharova

2000-01-01

254

Measuring freezing tolerance: electrolyte leakage and chlorophyll fluorescence assays.  

PubMed

Quantitative assessment of freezing tolerance is essential to unravel plant adaptations to cold temperatures. Not only the survival of whole plants but also impairment of detached leaves after a freeze-thaw cycle can be used to accurately quantify plant freezing tolerance in terms of LT50 values. Here we describe two methods to determine the freezing tolerance of detached leaves using different physiological parameters. Firstly, we illustrate how to assess the integrity of (predominantly) the plasma membrane during freezing using an electrolyte leakage assay. Secondly, we provide a chlorophyll fluorescence imaging protocol to determine the freezing tolerance of the photosynthetic apparatus. PMID:24852625

Thalhammer, Anja; Hincha, Dirk K; Zuther, Ellen

2014-01-01

255

Structural precursor to freezing in the hard-disk and hard-sphere systems  

NASA Astrophysics Data System (ADS)

We show that the simplest model fluids in two and three dimensions, namely, the hard-disk and hard-sphere fluids, exhibit a structural precursor to the freezing transition, which manifests itself as a shoulder in the second peak of the radial distribution function. This feature is not present in the radial distribution function of the low-density fluid. Close examination of the two-dimensional fluid configurations in the vicinity of the freezing transition reveals that the shoulder corresponds to the formation of a distinct structural motif, identifiable as a four-particle hexagonally close-packed arrangement. As the dense fluid approaches the freezing transition, the ordered arrangements form large embryonic domains, commensurate with those seen in the crystal at the melting point. Contrary to the notion that the split second peak is a signature of the amorphous solid, our results support the idea that it is a precursor to the development of long-range order.

Truskett, Thomas M.; Torquato, Salvatore; Sastry, Srikanth; Debenedetti, Pablo G.; Stillinger, Frank H.

1998-09-01

256

[Alzheimer's disease and depression].  

PubMed

In Alzheimer's disease (AD) patients, depression is not rare. The prevalence of major depressive episodes has been reported to be within the range of 20-25% in AD patients, despite there being no association between the severity of AD and prevalence of comorbid depressive symptoms or diagnosed depression. Depression in AD patients is associated with greater impairment of the quality of life and an increased caregiver burden. As well as earlier placement in a nursing home, bio-psycho-social factors are also associated with the manifestation of depression in AD patients, and biological factors, such as the brain pathology, may be the main influence. Depressive mood, loss of interest, and anxiety are among the most marked symptoms of depression in AD patients. In comparison with major depressive disorder, in depression in AD, psychomotor retardation is more prominent, while, in major depressive disorder, somatic anxiety is more marked. In the treatment of depression in AD, non-pharmacological and pharmacological therapies are applied. Basically, support and encouragement are required. In addition, psychosocial interventions, such as validation, reminiscence, physical exercise, and interventions for caregivers of those with dementia have been reported to be useful. The results of RCT with antidepressants are inconsistent. As the efficacy of cholinesterase inhibitor for depression in AD has been reported, it is reasonable to initially provide treatment with cholinesterase inhibitors rather than antidepressant therapy. PMID:24450144

Mizukami, Katsuyoshi

2013-01-01

257

Measuring salt and freezing temperature on roads  

NASA Astrophysics Data System (ADS)

Practical monitoring of the amount of salt spread on the road surface for de-icing purposes is technically difficult, especially if it has to be done in a commercially viable way. Possible solutions to this problem are discussed. As it has become customary to refer to the freezing temperature of a salted road, the physical meaning of such a temperature is scrutinised. It turns out that the meaning and the definition of freezing temperature are not clear, and that it also does not have the significance that is often associated with it. Some experimental results of salt measurements on a road are presented.

Turunen, Markus

1997-03-01

258

Freezing Characteristics of Molding Sand with Water by Cold Air Flow for Freeze Mold  

NASA Astrophysics Data System (ADS)

This paper reports the freezing characteristics of sand molded with "the freeze mold method". The freeze mold method is the casting process where little water is added to cast sand then they are frozen and become harden as a mold. Instead of using organic hardener, this molding technology possibly reduces resources and environment loading. We aimed at the practical application of the freeze mold method and chose cold airflow as the medium taking heat away from the mold. At first the sand with water was filled into a rectangular container that is the test section. Then cold air flowed into the container. Consequently, the mold was cooled and frozen by the cold airflow. The freezing behavior of the sample by cold airflow was investigated experimentally under the conditions of added water amount, superficial velocity, inflow air temperature and fixed bed height. As a result, the freezing completion time becomes long as the added water amount increases. However, an increase in the added water amount doesn't influence the pressure loss of the test section so much. Moreover, the empirical equation was derived to predict the freezing completion time.

Horibe, Akihiko; Inaba, Hideo; Haruki, Naoto; Miyagawa, Yasunori

259

Metabolic syndrome and major depressive disorder: Co-occurrence and pathophysiologic overlap  

Microsoft Academic Search

The metabolic syndrome and its components are associated with depressive symptomatology. This article discusses the rate of\\u000a co-occurrence and the points of pathophysiologic commonality between the metabolic syndrome and major depressive disorder.

Roger S. McIntyre; Natalie L. Rasgon; David E. Kemp; Ha T. Nguyen; Candy W. Y. Law; Valerie H. Taylor; Hanna O. Woldeyohannes; Mohammad T. Alsuwaidan; Joanna K. Soczynska; Byungsu Kim; Maria T. Lourenco; Linda S. Kahn; Benjamin I. Goldstein

2009-01-01

260

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

PubMed

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. © 2014 European Union 103:2088-2097, 2014. PMID:24902839

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

2014-07-01

261

Process feasibility investigation of freezing free litho-litho-etch process for below 32nm hp  

NASA Astrophysics Data System (ADS)

Double patterning with 193nm immersion lithography becomes to most promising candidate for 32nm half pitch node and possibly below 32nm half pitch. Several double patterning methods have been suggested such as LELE (Litho-Etch -Litho-Etch), LLE (Litho-Litho-Etch) and Spacer defined process, however, LLE process is pointed out as low cost double patterning technique because of its simplicity. But LLE process needs new method to maintain 1st lithography pattern and additional freezing processes have been suggested In SPIE Advanced Lithography 2009, freezing free "Posi/Posi" process was introduced as candidate for LLE process. This is LLE process that uses two different positive tone photoresists without freezing process. The resist for 2nd lithography contains a specific solvent to prevent the mixing of two resists and there is an activation energy gap between 1st and 2nd resists to maintain 1st lithography pattern. The double patterning can be successfully processed by these specific resists without freezing process. In this study, the performance of this freezing free "Posi/Posi" process is investigated for pitch splitting pattern using 1.35 NA exposure tool. The imaging results including CD control capability, and etching results are collected for 32nm half pitch and below. Additionally the two-dimensional pattern imaging is also obtained for 76nm minimum pitch.

Nakamura, Tsuyoshi; Takeshita, Masaru; Yokoya, Jiro; Yoshii, Yasuhiro; Saito, Hirokuni; Takasu, Ryoichi; Ohmori, Katsumi

2010-03-01

262

Do You Have Major Depression?  

MedlinePLUS

... of this page please turn Javascript on. Feature: Depression Do You Have Major Depression? Past Issues / Fall 2009 Table of Contents Simple ... member may have major depression. —NIMH Types of Depression Just like other illnesses, such as heart disease, ...

263

Major depression with psychotic features  

MedlinePLUS

... depression along with loss of touch with reality (psychosis). See also: Major depression Psychosis ... with psychotic depression have symptoms of depression and psychosis. Psychosis is a loss of contact with reality. ...

264

Metabolic depression: a historical perspective.  

PubMed

An extended period of inactivity and reduced metabolic rate of many animals and plants, as well as unicellular organisms, has long been recognized by natural historians, e.g., Aristotle and Pliny. Biologists have studied this phenomenon since the 1550s (Gessner) and 1700s (Van Leeuwenhoek, Buffon). The period of inactivity can be less than a day, a few consecutive days or weeks, an entire season, or even many years. It can involve very different physiological states in response to a variety of environmental stimuli, such as extreme temperatures or unavailability of food or water. These periods of inactivity have been described and classified according to the group of organisms in question, extent and duration of the metabolic depression, ambient and body temperatures, state of body water (frozen or hyperosmotic), or availability of oxygen. Cryptobiosis, or "hidden life," is an extreme form of inactivity, with often complete cessation of metabolism. It was first described in the 1700s, was further characterized in the 1800s, and in the 1900s physiological studies delineated the extent of metabolic depression. Molecular mechanisms for cryptobiosis have been sought since the late 1900s. Cryptobiosis includes three physiological states, anhydrobiosis (desiccation), osmobiosis (high osmotic concentration), and cryobiosis (freezing), where metabolic depression is associated with an altered physical state of cell water and often involves accumulation of compatible solutes, and one physiological state, anoxybiosis (anoxia), where metabolic depression occurs at the normal cellular hydration state. Dormancy (torpor) is a less extreme form of inactivity, associated with a moderate reduction in metabolic rate (hypometabolism). Although first described by Aristotle and Pliny, studies in the 1900s delineated the basic physiological changes that accompany dormancy. Dormancy allows avoidance of unfavorable short- or long-term climatic conditions and conservation of energy and water. Hibernation is long-term multiday torpor during winter, whereas aestivation is dormancy during summer. In ectotherms, the metabolic depression that accompanies dormancy is intrinsic, with metabolic rate declining to about 10 to 20% of resting metabolic rate at the same body temperature. The molecular mechanisms for intrinsic metabolic depression are poorly understood. In endotherms, torpor involves a fundamental physiological change in body temperature regulation that markedly reduces metabolic rate and water loss, often to <10% of the normothermic resting metabolic rate at the same ambient temperature. Most of this reduction in metabolic rate reflects the decreased setpoint for thermoregulation resulting in reduced metabolic heat production and a Q(10) effect; there may be some intrinsic molecular-based metabolic depression in some hibernators. Dormancy allows species to exploit ephemeral environments and colonise habitats that would otherwise be unsuitable for growth or survival at certain times of the year. There are costs to dormancy, but for many species, the energetic and hygric advantages outweigh these costs. PMID:20069402

Withers, Philip C; Cooper, Christine E

2010-01-01

265

Postpartum Depression Action Plan  

MedlinePLUS

MENU Return to Web version Postpartum Depression | Postpartum Depression Action Plan Patient __________________________ Physician/NP/PA __________________ Clinic ____________________________ Phone Number ____________________ Choose one area and add other areas as you begin to ...

266

Older Adults and Depression  

MedlinePLUS

... treatment. If left untreated, depression can lead to suicide. Depression is a common problem among older adults, ... not wanting to eat at all Thoughts of suicide, suicide attempts Aches or pains, headaches, cramps, or ...

267

Depression in Indian history.  

PubMed

This write up on some aspects of Indian history of depression touches briefly on references to some aspects of depression in Ayurveda, in philosophical texts and in the epics Ramayana and Mahabharata. PMID:11002619

Rao, A V

2000-05-01

268

Screening for Depression  

MedlinePLUS

... be used without permission. Education Mood Disorders Depression Bipolar Disorder Anxiety Screening Center Co-occurring Illnesses/Disorders ... wellness for people who live with depression and bipolar disorder. Because DBSA was created for and is ...

269

How Is Depression Diagnosed?  

MedlinePLUS

... Harvard Medical Content 2012-03-05 How Is Depression Diagnosed? Diagnosis means "to know." The more health- ... all medical problems, including psychiatric ones. To diagnose depression, your health-care provider will probably perform the ...

270

Genetic biomarkers of depression  

PubMed Central

Depression is a term that has been used to describe a variety of ailments, ranging from minor to incapacitating. Clinically significant depression, termed as major depression, is a serious condition characterized not only by depressed mood but also by a cluster of somatic, cognitive, and motivational symptoms. Significant research efforts are aimed to understand the neurobiological as well as psychiatric disorders, and the evaluation of treatment of these disorders is still based solely on the assessment of symptoms. In order to identify the biological markers for depression, we have focused on gathering information on different factors responsible for depression including stress, genetic variations, neurotransmitters, and cytokines and chemokines previously suggested to be involved in the pathophysiology of depression. The present review illustrates the potential of biomarker profiling for psychiatric disorders, when conducted in large collections. The review highlighted the biomarker signatures for depression, warranting further investigation.

Tamatam, Anand; Khanum, Farhath; Bawa, Amarinder Singh

2012-01-01

271

Nondysphoric depression following stroke.  

PubMed

Right hemisphere damage may influence the presentation of depressive disorders ensuing after stroke by disrupting emotion processing mechanisms. Three-hundred and one consecutive admissions for acute stroke were examined and subjects meeting previously validated criteria for nondysphoric depression (i.e., depressive ideation without endorsement of sad emotions) were compared to dysphoric depression, and to nondepressed patients. Compared to dysphoric depression, nondysphoric depression showed more frequent right anterior hemisphere lesions and more psychomotor slowing, self-depreciation, and severe sad affect. Psychopathological features and location of damage suggest that nondysphoric depression may be a special presentation of depressive disorder following stroke in which right hemisphere damage limits the apprehension of personal emotional changes. PMID:18305284

Paradiso, Sergio; Vaidya, Jatin; Tranel, Daniel; Kosier, Todd; Robinson, Robert G

2008-01-01

272

Method of treating depression  

DOEpatents

Methods for treatment of depression-related mood disorders in mammals, particularly humans are disclosed. The methods of the invention include administration of compounds capable of enhancing glutamate transporter activity in the brain of mammals suffering from depression. ATP-sensitive K.sup.+ channel openers and .beta.-lactam antibiotics are used to enhance glutamate transport and to treat depression-related mood disorders and depressive symptoms.

Henn, Fritz

2013-04-09

273

National Costs of Depression  

Microsoft Academic Search

A depressive disorder is an illness that involves the body, mood, and thoughts. Major depression is manifested by feelings of sadness, anxiety, pessimism, and low self-esteem that interfere with normal functioning. Depression involves changes to brain chemistry and imbalances in neurotransmitters. A less severe or common form of depres- sion is dysthymia, which many not disable, but can keep one

274

Depression and Heart Disease  

MedlinePLUS Videos and Cool Tools

... player. Depression and Heart Disease HealthDay June 19, 2014 Related MedlinePlus Pages Depression Heart Disease in Women Women's Health Transcript Young women struggling with depression face a higher risk of suffering a heart attack new research reveals. Young women also face more than twice ...

275

Prevention of Depression.  

ERIC Educational Resources Information Center

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…

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

276

Reward and anxiety in genetic animal models of childhood depression.  

PubMed

One of the most important criteria for major depressive disorder in adults and in children and adolescents as well, is the loss of interest in or pleasure from typically enjoyable experiences or activities: anhedonia. Anxiety is frequently co-morbid with depression. We examined reward and anxiety in genetic animal models of childhood depression. Two different "depressed" lines were studied: the Flinders Sensitive Line (FSL) and their controls, Sprague-Dawley (SD) rats and the Wistar Kyoto (WKY) line and their controls, Wistar rats. Recently, we found that prepubertal rats (about 35 days old) from these lines exhibited increased immobility in the swim test, and abnormal social play observed after 24-h isolation. We hypothesized that FSL and WKY prepubertal rats will further show anhedonia in two different behavioral assays: the conditioned place preference test (CPP), examining the rewarding aspect of social interaction and the saccharin preference test. Behavior in the open field paradigm and freezing behavior in the CPP apparatus were also used as measures of anxiety. WKY, but not FSL prepubertal rats, consumed less of the saccharin solution compared to their control line. FSL, and WKY prepubertal rats found social interaction to be rewarding to a similar extent as their control lines, in the CPP test. Only the WKY rats showed anxiety in behavior in the open field and freezing behavior in the CPP paradigm. The results suggest that WKY prepubertal rats are anxious and sensitive to stress-induced anhedonia, while FSL prepubertal rats exhibit none of these symptoms. PMID:16055204

Malkesman, O; Braw, Y; Zagoory-Sharon, O; Golan, O; Lavi-Avnon, Y; Schroeder, M; Overstreet, D H; Yadid, G; Weller, A

2005-10-14

277

7 CFR 58.638 - Freezing the mix.  

Code of Federal Regulations, 2010 CFR

...false Freezing the mix. 58.638 Section...Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT...UNDER THE AGRICULTURAL MARKETING ACT OF 1946 AND THE...638 Freezing the mix. After the...

2010-01-01

278

7 CFR 58.638 - Freezing the mix.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 false Freezing the mix. 58.638 Section 58.638 Agriculture...Agriculture (Continued) AGRICULTURAL MARKETING SERVICE, DEPARTMENT OF AGRICULTURE...Procedures § 58.638 Freezing the mix. After the mix enters the...

2009-01-01

279

Perceptions of depression among recovered-depressed and never-depressed individuals.  

PubMed

Research on lay beliefs about depression has shown that recovered-depressed people evaluate their own depressive experiences as more distressing than do those who have never experienced major depression. This study tested whether history of depression would influence beliefs about others' experiences of depression. Recovered-depressed (n = 63) and never-depressed adults (n = 64) completed the Self-Appraisal Questionnaire (R-SAQ; J.C. Coyne & M.M. Calarco, 1995) revised to address perceptions of others' experiences of depression. History of depression was not associated with R-SAQ scores. In supplementary analyses, self-reported depression proneness was also uncorrelated with perceptions of others' depression. People without a history of major depression were just as likely to recognize the highly debilitating nature of depression for others. Although nondepressed people frequently fail to convey empathy to friends or relatives who are depressed, this failure probably does not reflect lack of knowledge that depression is incapacitating. PMID:16538660

Wernicke, Rachel A; Pearlman, Michelle Y; Thorndike, Frances P; Haaga, David A F

2006-06-01

280

Clinical and molecular genetics of psychotic depression.  

PubMed

This review provides a comprehensive overview of clinical and molecular genetic as well as pharmacogenetic studies regarding the clinical phenotype of "psychotic depression." Results are discussed with regard to the long-standing debate on categorical vs dimensional disease models of affective and psychotic disorders on a continuum from unipolar depression over bipolar disorder and schizoaffective disorder to schizophrenia. Clinical genetic studies suggest a familial aggregation and a considerable heritability (39%) of psychotic depression partly shared with schizoaffective disorder, schizophrenia, and affective disorders. Molecular genetic studies point to potential risk loci of psychotic depression shared with schizoaffective disorder (1q42, 22q11, 19p13), depression, bipolar disorder, and schizophrenia (6p, 8p22, 10p13-12, 10p14, 13q13-14, 13q32, 18p, 22q11-13) and several vulnerability genes possibly contributing to an increased risk of psychotic symptoms in depression (eg, BDNF, DBH, DTNBP1, DRD2, DRD4, GSK-3beta, MAO-A). Pharmacogenetic studies implicate 5-HTT, TPH1, and DTNBP1 gene variation in the mediation of antidepressant treatment response in psychotic depression. Genetic factors are suggested to contribute to the disease risk of psychotic depression in partial overlap with disorders along the affective-psychotic spectrum. Thus, genetic research focusing on psychotic depression might inspire a more dimensional, neurobiologically and symptom-oriented taxonomy of affective and psychotic disorders challenging the dichotomous Kraepelinian view. Additionally, pharmacogenetic studies might aid in the development of a more personalized treatment of psychotic depression with an individually tailored antidepressive/antipsychotic pharmacotherapy according to genotype. PMID:23512949

Domschke, Katharina

2013-07-01

281

Unitarity Constraints on Asymmetric Freeze-In  

SciTech Connect

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.

Hook, Anson; /SLAC

2011-08-15

282

Polybutylene pipe freeze/thaw reliability testing  

SciTech Connect

This paper discusses the ability of polybutylene pipe to withstand repeated freezing and thawing. The test apparatus, test procedure, list of chronological events, and results are discussed. Polybutylene piping has potential use in active solar heating systems and integral-collector-storage systems.

Farrington, R.B.

1987-04-01

283

Cryogenic Pipe Freezing - A Theoretical Model.  

National Technical Information Service (NTIS)

A theoretical simplified model for cryogenic pipe freezing, which is based on a steady-state approximation, has been developed in this work. A comparison with experimental results shows a relatively good agreement with the heat flux data obtained from dir...

H. Tinoco

1988-01-01

284

Global Annual Freezing and Thawing Indices  

NSDL National Science Digital Library

The National Snow and Ice Data Center provide these data showing the "cumulative number of degree-days when air temperatures are below and above zero degrees Celsius." Two data files, one each for the freezing and thaw data, and a readme file are available. A Fortran program is provided in the data documentation to read the data that are in flat binary format.

285

Fast hadron freeze-out generator  

NASA Astrophysics Data System (ADS)

We have developed a fast Monte Carlo procedure of hadron generation that allows one to study and analyze various observables for stable hadrons and hadron resonances produced in ultrarelativistic 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 parametrization or a numerical solution of relativistic hydrodynamics with given initial conditions and equation of state. Besides standard spacelike sectors associated with the volume decay, the hypersurface may also include nonspacelike 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 parametrizations 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/.

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

2006-12-01

286

Freezing, Thawing, and Packaging Cells for Transport  

PubMed Central

Cultured mammalian cells are used extensively in cell biology studies. It requires a number of special skills in order to be able to preserve the structure, function, behavior, and biology of the cells in culture. This video describes the basic skills required to freeze and store cells and how to recover frozen stocks.

Ricardo, Richard; Phelan, Katy

2008-01-01

287

Melting, freezing, and coalescence of gold nanoclusters  

Microsoft Academic Search

We present a detailed molecular-dynamics study of the melting, freezing, and coalescence of gold nanoclusters within the framework of the embedded-atom method. Concerning melting, we find the process first to affect the surface (``premelting''), then to proceed inwards. The curve for the melting temperature vs cluster size is found to agree reasonably well with predictions of phenomenological models based on

Laurent J. Lewis; Pablo Jensen; Jean-Louis Barrat

1997-01-01

288

Effects of Repeated Freezing on Paper Strength.  

National Technical Information Service (NTIS)

The report describes an investigation into the effects of repeated freezing on paper strength. Six different papers from the Swedish National Testing Institute's collection of tested paper from the period 1920-1921 were chosen. Three papers made of rag pu...

M. Antonsson M. L. Samuelsson

1996-01-01

289

Risk factors for depressive symptomatology in a drug using population.  

PubMed Central

This study employs a prospective design to examine possible personality, drug use, stressful life event, and social support-related variables associated with the onset of a depressive episode in a cohort of psychoactive drug using young adults. Two waves of data, collected one year apart, were available on 942 individuals. Cases (n = 62) were free of depressive symptoms at time 1 but reported significant symptomatology at time 2 as measured by the depression subscale of the Brief Symptom Inventory. Controls (n = 490) were those free of depressive symptoms at both time points. In multivariate analyses, users of the central nervous system depressant methaqualone had a nearly four-fold elevated risk for depressed mood as compared to nonusers. Additional risk factors significant after multivariate adjustment included lower self-esteem at time 1 and negative life events. These results highlight the multifactorial nature of depressive symptomatology.

Buckner, J C; Mandell, W

1990-01-01

290

The SENSITIVE TO FREEZING2 Gene, Required for Freezing Tolerance in Arabidopsis thaliana, Encodes a ?-Glucosidase  

PubMed Central

The sensitive to freezing2-1 (sfr2-1) mutation causes freezing sensitivity in Arabidopsis thaliana. By mapping, transgenic complementation, and sequencing, sfr2-1 was revealed to be a mutation in gene At3g06510. A new knockout allele was obtained, and its identical freezing-sensitive phenotype confirmed that the SFR2 gene product is essential for freezing tolerance. Transcription of SFR2 was observed to be constitutive rather than stress inducible and was distributed throughout most aerial tissues. SFR2 encodes a protein homologous to family 1 glycosyl hydrolases (?-glycosidases), but the predicted AtSFR2 protein is divergent from all other family 1 ?-glycosidases of Arabidopsis, showing closer homology to the sequences of several ?-glycosidases from thermophilic archea and bacteria. After purification from a heterologous expression system, AtSFR2 displayed a specific hydrolytic activity against ?-d-glucosides.

Thorlby, Glenn; Fourrier, Nicolas; Warren, Gareth

2004-01-01

291

Ultrasonic emissions from conifer xylem exposed to repeated freezing  

Microsoft Academic Search

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,

Stefan Mayr; Verena Zublasing

2010-01-01

292

Real-time frame-freezing detection system evaluation  

Microsoft Academic Search

This paper describes implementation and evaluation of real-time system for frame-freezing detection in video signals. Frame freezing effect is manifested in cut scenes in video on end-user display devices, which significantly reduces visual quality. In order to efficiently monitor and detect this effect in multimedia systems we propose a realtime frame-freezing detection system that incorporates previously developed frame-freezing detection algorithm.

Darko Lulic; Zoran Marceta; Nikola Vranic; Vladimir Zlokolica; Miodrag Temerinac

2011-01-01

293

Aquaporin-mediated improvement of freeze tolerance of Saccharomyces cerevisiae is restricted to rapid freezing conditions.  

PubMed

Previous observations that aquaporin overexpression increases the freeze tolerance of baker's yeast (Saccharomyces cerevisiae) without negatively affecting the growth or fermentation characteristics held promise for the development of commercial baker's yeast strains used in frozen dough applications. In this study we found that overexpression of the aquaporin-encoding genes AQY1-1 and AQY2-1 improves the freeze tolerance of industrial strain AT25, but only in small doughs under laboratory conditions and not in large doughs under industrial conditions. We found that the difference in the freezing rate is apparently responsible for the difference in the results. We tested six different cooling rates and found that at high cooling rates aquaporin overexpression significantly improved the survival of yeast cells, while at low cooling rates there was no significant effect. Differences in the cultivation conditions and in the thawing rate did not influence the freeze tolerance under the conditions tested. Survival after freezing is determined mainly by two factors, cellular dehydration and intracellular ice crystal formation, which depend in an inverse manner on the cooling velocity. In accordance with this so-called two-factor hypothesis of freezing injury, we suggest that water permeability is limiting, and therefore that aquaporin function is advantageous, only under rapid freezing conditions. If this hypothesis is correct, then aquaporin overexpression is not expected to affect the leavening capacity of yeast cells in large, industrial frozen doughs, which do not freeze rapidly. Our results imply that aquaporin-overexpressing strains have less potential for use in frozen doughs than originally thought. PMID:15184134

Tanghe, An; Van Dijck, Patrick; Colavizza, Didier; Thevelein, Johan M

2004-06-01

294

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

Microsoft Academic Search

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

Shan Jiang; Steven L Nail

1998-01-01

295

[Depression and diet ].  

PubMed

Especially low vitamin B12 or folate and low intake of omega-3-fatty acids, but also low vitamin D may associate with increased risk of depression. B12 and folate may also be useful in the treatment of depression. The importance of individual fatty acids is unclear. The causal relationship between depression and diet, the efficacy of vitamins or dietary supplements in the treatment of depression, or the impact of diet compared with other treatment options need to be scrutinized. An overall healthy diet rich in vitamin B12, D or folate and fish oils may have positive effect also on depression. PMID:24881142

Seppälä, Jussi; Kauppinen, Anne; Kautiainen, Hannu; Vanhala, Mauno; Koponen, Hannu

2014-01-01

296

Understanding childhood depression.  

PubMed

Major depressive disorder in children is a severe and a chronically disabling disorder. This population appears to be a special group in terms of consequences of poor psychosocial and academic outcome and increased risk of substance abuse, and suicide. Studies have revealed several major findings in genetic, familial, psychological, and biological aspects of such depression, some of which have explored into the issue of its relationship with adult depression. Considerable advances have been made now in the area of childhood depression providing a better understanding of its nature. We review literature available on historical aspect, epidemiology, clinical characteristics, and aetiology of childhood depression. PMID:17431280

Malhotra, Savita; Das, Partha Pratim

2007-02-01

297

Freezing in Parkinson's disease: a spatiotemporal motor disorder beyond gait.  

PubMed

Freezing of gait (FOG) is an incapacitating problem in Parkinson's disease that is difficult to manage therapeutically. We tested the hypothesis that impaired rhythm and amplitude control is a common mechanism of freezing which is also present during other rhythmic tasks. Therefore, we compared the occurrence and spatiotemporal profiles of freezing episodes during upper limb motion, lower limb motion, and FOG. Eleven freezers, 12 non-freezers, and 11 controls performed a rhythmic bilateral finger movement task. The triggering effect of movement speed, amplitude, and coordination pattern was evaluated. Regression slopes and spectral analysis addressed the spatial and temporal kinematic changes inherent to freezing episodes. The FOG Questionnaire score significantly predicted severity of upper limb freezing, present in 9 freezers, and of foot freezing, present in 8 freezers. Similar to gait, small-amplitude movements tended to trigger upper limb freezing, which was preceded by hastened movement and a strong amplitude breakdown. Upper limb freezing power spectra were broadband, including increased energy in the "freeze band" (3-8 Hz). Contrary to FOG, unilateral upper limb freezing was common and occurred mainly on the disease-dominant side. The findings emphasize that a core motor problem underlies freezing which can affect various movement effectors. This deficit may originate on the disease-dominant body side and interfere with amplitude and timing regulation during repetitive limb movements. These results may shift current thinking on the origins of freezing as being not exclusively a gait failure. PMID:22020744

Vercruysse, Sarah; Spildooren, Joke; Heremans, Elke; Vandenbossche, Jochen; Levin, Oron; Wenderoth, Nicole; Swinnen, Stephan P; Janssens, Luc; Vandenberghe, Wim; Nieuwboer, Alice

2012-02-01

298

Modification of physical properties of freeze-dried rice  

NASA Technical Reports Server (NTRS)

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.

Huber, C. S.

1971-01-01

299

Factors Influencing Freezing of Supercooled Water in Tender Plants1  

Microsoft Academic Search

Seedlings of beans (Phaseolus vulgaris), corn (Zea mays), and tomatoes (Lycopersicon esculentum) were grown in the greenhouse and then exposed to controlled freezing conditions in a growth chamber. Variables were adjusted to determine the influence of plant water potential, freez- ing time, and external dew formation on the seedlings' susceptibility to frost injury. Freezing, detected visually and by release of

J. W. Cary

1970-01-01

300

Controlling the freezing process: a robotic device for rapidly freezing biological tissues with millisecond time resolution.  

PubMed

A robotic cryogenic device was developed which allows freezing of thick biological tissues with millisecond time resolution. The device consists of two horizontally oriented hammers (pre-cooled with liquid N(2)) driven by two linear servo-motors. The tissue sample is bathed in Ringers contained in a chamber which drops rapidly out of the way just as the hammers approach. A third linear motor is vertically oriented, and permits the rapidly dropping chamber to smoothly decelerate. All movements were performed by the three motors and four solenoids controlled by a PC. Mechanical adjustments, that change the size of the gap between the hammers at the end position, permit the final thickness of the frozen tissue to be varied. Here we show that the freezing time increased with the square of the final thickness of the frozen bundle. However, when bundles of different original thicknesses (up to at least 1mm) were compressed to the same final thickness (e.g., 0.2mm), they exhibited nearly equal freezing times. Hence, by being able to adjust the final thickness of the frozen bundles, the device not only speeds the rate of freezing, but standardizes the freezing time for different diameter samples. This permits the use of freezing for accurate determination of the kinetics of cellular processes in biological tissue. PMID:17640628

Tikunov, Boris A; Rome, Lawrence C

2007-10-01

301

Depressive symptoms in institutionalized older adults.  

PubMed

OBJECTIVE To estimate the prevalence of depressive symptoms among institutionalized elderly individuals and to analyze factors associated with this condition. METHODS This was a cross-sectional study involving 462 individuals aged 60 or older, residents in long stay institutions in four Brazilian municipalities. The dependent variable was assessed using the 15-item Geriatric Depression Scale. Poisson's regression was used to evaluate associations with co-variables. We investigated which variables were most relevant in terms of presence of depressive symptoms within the studied context through factor analysis. RESULTS Prevalence of depressive symptoms was 48.7%. The variables associated with depressive symptoms were: regular/bad/very bad self-rated health; comorbidities; hospitalizations; and lack of friends in the institution. Five components accounted for 49.2% of total variance of the sample: functioning, social support, sensory deficiency, institutionalization and health conditions. In the factor analysis, functionality and social support were the components which explained a large part of observed variance. CONCLUSIONS A high prevalence of depressive symptoms, with significant variation in distribution, was observed. Such results emphasize the importance of health conditions and functioning for institutionalized older individuals developing depression. They also point to the importance of providing opportunities for interaction among institutionalized individuals. PMID:24897042

Santiago, Lívia Maria; Mattos, Inês Echenique

2014-04-01

302

Early Childhood Depression  

PubMed Central

Although empirical evidence has recently validated clinical depression in children as young as age 3, few data are available to guide treatment of early childhood depression. Considering this gap in the literature, a novel dyadic psychotherapeutic model, Parent Child Interaction Therapy–Emotion Development, based on a well-known and effective manualized treatment for disruptive preschoolers, is currently being tested for use in depression. To balance safety and efficacy, dyadic developmental approaches are currently recommended as the first line of treatment for preschool depression. In the absence of data on the safety and efficacy of antidepressants in preschool depression, these agents are not recommended as a first- or second-line treatment at this time. This article provides an illustrative case example of preschool depression, outlines key considerations in differential diagnosis, and describes this novel form of treatment. It also clarifies parameters for the rare situations in which antidepressants may be tried when psychotherapeutic options fail and depression is severe and impairing.

Luby, Joan L

2010-01-01

303

Depression in adolescence  

PubMed Central

Unipolar depressive disorder in adolescence is common worldwide but often unrecognised. The incidence, notably in girls, rises sharply after puberty and, by the end of adolescence, the 1 year prevalence rate exceeds 4%. The burden is highest in low-income and middle-income countries. Depression is associated with sub stantial present and future morbidity, and heightens suicide risk. The strongest risk factors for depression in adolescents are a family history of depression and exposure to psychosocial stress. Inherited risks, developmental factors, sex hormones, and psychosocial adversity interact to increase risk through hormonal factors and associated perturbed neural pathways. Although many similarities between depression in adolescence and depression in adulthood exist, in adolescents the use of antidepressants is of concern and opinions about clinical management are divided. Effective treatments are available, but choices are dependent on depression severity and available resources. Prevention strategies targeted at high-risk groups are promising.

Thapar, Anita; Collishaw, Stephan; Pine, Daniel S; Thapar, Ajay K

2012-01-01

304

Foam-Mat Freeze Drying of Egg White—Mathematical Modeling Part II: Freeze Drying and Modeling  

Microsoft Academic Search

Foam-mat freeze drying is one of the promising methods of drying, which utilizes advantages of both freeze drying and foam-mat drying. Egg white with its excellent foaming properties makes a suitable candidate for foam-mat freeze drying. Experiments were conducted to study foam-mat freeze drying of egg white, in an effort to determine the suitability of this method. Xanthan gum (XG)

Arun Muthukumaran; Cristina Ratti; Vijaya G. S. Raghavan

2008-01-01

305

Microstructure and adsorption properties of gelatinized-tapioca starch beads modified by freezing and a freeze-drying method  

Microsoft Academic Search

The effects of two freezing methods: slow freezing (SF) at -20°C for 24 hours, and quick freezing (QF) at -176°C for 5-10 min and three commercial brands of Golden Chef®, Special Sacoo® or Thaiworld® on moisture content, microstructure, porosity, total bulk volume, adsorption properties (initial adsorption, adsorption capacity and adsorption behaviour) and gel strength of freeze-dried-gelatinized tapioca starch beads (FDTB)

P. Rattanapitigorn; P. Raviyan; C. Khanongnuch; L. Ozimek

306

Supercooling of type 1 polar stratospheric clouds: The freezing of submicron nitric acid aerosols having HNO3 mol fractions less than 0.5  

NASA Astrophysics Data System (ADS)

We report the freezing temperatures for nitric acid/water aerosol particles having radii about 0.2 ?m and concentrations in the range 0.24 < xHNO3 < 0.46 (xHNO3 = nitric acid mol fraction). The aerosols supercool by up to 85 K. The droplets having xHNO3 = 0.33 have the highest freezing point in this concentration range; they supercool by 60 K and produce nitric acid dihydrate (NAD) upon freezing. We describe a simplified principal components analysis that improves the detection of the freezing point and allows the identification of the solid that precipitates upon freezing. This procedure shows that for the temperature range and experimental conditions explored, only NAD precipitates in the concentration range 0.33 < xHNO3 < 0.42 and both NAD and nitric acid trihydrate (NAT) precipitate for the range 0.24 < xHNO3 < 0.33. The temperature dependences of our measured freezing points correlate strongly with NAD saturation ratios, but have no relationship with NAT supersaturation at any concentration. Thus NAD nucleates preferentially from supercooled aerosols in this composition range, probably because of kinetic constraints on the nucleation of NAT. We conclude that NAD nucleation is possible during rapid cooling events in the polar stratosphere, if temperatures lower than 185 K are reached. During the freezing of stratospheric aerosol droplets in this concentration range, it seems likely that NAD nucleates first, thereby providing a surface on which NAT may crystallize.

Bertram, A. K.; Dickens, D. B.; Sloan, J. J.

2000-04-01

307

Definition of Hydrologic Response Units in Depression Plagued Digital Elevation Models  

NASA Astrophysics Data System (ADS)

Definition of hydrologic response units using digital elevation models (DEMs) is sensitive to the occurrence of topographic depressions. Real depressions can be important to the hydrology and biogeochemistry a catchment, often coinciding with areas of surface saturation. Artifact depressions, in contrast, result in digital "black holes", artificially truncating the hydrologic flow lengths and altering hydrologic flow directions, parameters that are often used in defining hydrologic response units. Artifact depressions must be removed from DEMs prior to definition of hydrologic response units. Depression filling or depression trenching techniques can be used to remove these artifacts. Depression trenching methods are often considered more appropriate because they preserve the topographic variability within a depression thus avoiding the creation of spurious flat areas. Current trenching algorithms are relatively slow and unable to process very large or noisy DEMs. A new trenching algorithm that overcomes these limitations is described. The algorithm does not require finding depression catchments or outlets, nor does it need special handling for nested depressions. Therefore, artifacts can be removed from large or noisy DEMs efficiently, while minimizing the number of grid elevations requiring modification. The resulting trench is a monotonically descending path starting from the lowest point in a depression, passing through the depression's outlet, and ending at a point of lower elevation outside the depression. The importance of removing artifact depressions is demonstrated by showing hydrologic response units both before and after the removal of artifact depressions from the DEM.

Lindsay, J. B.; Creed, I. F.

2002-12-01

308

The effects of freeze drying and freeze drying additives on the prothrombin time and the international sensitivity index  

Microsoft Academic Search

AIM: To determine whether freezing, freeze drying protective additives, or freeze drying of plasma samples from patients on coumarin treatment and from normal individuals affects prothrombin times or the international sensitivity index (ISI) calibration. METHODS: The effect of the addition of the protective additives singly and combined on the prothrombin time of coumarin samples and normal samples before and after

L. Poller; M. Keown; S. A. Shepherd; C. R. Shiach; S. Tabeart

1999-01-01

309

Wetting, Freezing and Capillary Condensation in Porous Media  

NASA Astrophysics Data System (ADS)

In recent torsional oscillator experiments on porous Vycor partially filled with hydrogen, the oscillator frequency began to increase at a characteristic temperature below the bulk triple point. This was interpreted to mean that hydrogen was being expelled from the pores. (M.Schindler, A.Dertinger, Y.Kondo and F.Pobell, Phys. Rev. B53, 11451 (1996).) Since this effect has not been seen in other measurements involving liquids in porous media, we have used an ultrasonic technique to study the adsorption of a simple liquid, argon, in Vycor. Above the bulk triple point, adsorption isotherms show wetting and eventually capillary condensation in the pores. Below argon's triple point (84 K), however, the suppression of freezing in the pores results in a free energy which is larger for the confined liquid than for bulk. Argon then preferentially forms solid outside the Vycor sample resulting in incomplete filling of the Vycor for isotherms below the bulk triple point. Argon may even leave the pores as the sample is cooled.

Paetkau, Mark; Beamish, John

1997-03-01

310

Spacecraft Radiator Freeze Protection Using a Regenerative Heat Exchanger  

NASA Technical Reports Server (NTRS)

An active thermal control system architecture has been modified to include a regenerative heat exchanger (regenerator) inboard of the radiator. Rather than using a radiator bypass valve a regenerative heat exchanger is placed inboard of the radiators. A regenerator cold side bypass valve is used to set the return temperature. During operation, the regenerator bypass flow is varied, mixing cold radiator return fluid and warm regenerator outlet fluid to maintain the system setpoint. At the lowest heat load for stable operation, the bypass flow is closed off, sending all of the flow through the regenerator. This lowers the radiator inlet temperature well below the system set-point while maintaining full flow through the radiators. By using a regenerator bypass flow control to maintain system setpoint, the required minimum heat load to avoid radiator freezing can be reduced by more than half compared to a radiator bypass system.

Ungar, Eugene K.; Schunk, Richard G.

2011-01-01

311

Psychosocial factors associated with depression severity in pregnant adolescents  

PubMed Central

Adolescent depression during pregnancy is associated with increased morbidity for the teen and her infant. This cross-sectional study explored the relationships among the independent histories of alcohol use, drug use, depression, and abuse (physical or sexual) on depression severity in a diverse group of 116 pregnant adolescents (mean age=16) who attended an urban prenatal clinic. Ever having had an alcoholic drink was a significant predictor of higher depressive scores on Children's Depression Rating Scale-Revised, ?=3.3 (0.8, 5.7); p<0.05. History of abuse was associated with a significant 4.3-point higher mean depressive score, ?=4.3 (1.8, 6.7), p<0.001, and remained a statistically significant predictor of more severe depressive symptoms after adjustment for history of alcohol use, history of drug use, and history of depression. This study identified that a history of physical or sexual abuse is a significant factor related to the severity of depressive symptoms in pregnant adolescents, independent of a history of alcohol, drug use, or depression. These findings suggest that an assessment of history of alcohol use, as well as abuse history, may increase the likelihood of identifying adolescents at risk for antenatal depression.

Zlotnick, Caron; Raker, Christina; Kuo, Caroline; Phipps, Maureen G.

2014-01-01

312

Depression and Parkinson's disease.  

PubMed

Depression occurs in approximately 45% of all patients with Parkinson's disease (PD), reduces quality of life independent of motor symptoms and seems to be underrated and undertreated. Characteristics of symptoms differ from major depression. Because of overlapping clinical symptoms, diagnosis is based on subjectively experienced anhedonia and feeling of emptiness. Available rating scales for major depression may not be adequate to correctly measure severity of depression in PD. Anxiety and depression may manifest as first symptoms of PD many years before motor symptoms. Serotonergic, noradrenergic and dopaminergic mechanisms play key roles in the etiology of depression in PD. Tricyclic and newer, selective antidepressants including serotonin and noradrenaline reuptake inhibitors (SSRI, SNRI) appear to be effective in treating depression in PD. Selective reuptake inhibitors seem to have a favorable side effect profile. Recent controlled studies show antidepressant effects of pramipexole in bipolar II depression. New dopamine agonists pramipexole and ropinirole appear to ameliorate depressive symptoms in PD in addition to effects on motor symptoms. There is a lack of appropriate rating scales and controlled studies regarding depression in PD. PMID:15675721

Lemke, Matthias R; Fuchs, Gerd; Gemende, Irene; Herting, Birgit; Oehlwein, Christian; Reichmann, Heinz; Rieke, Jürgen; Volkmann, Jens

2004-09-01

313

Depression Predicts All-Cause Mortality  

PubMed Central

OBJECTIVE Depression affects up to 20–25% of adults with type 2 diabetes and may increase all-cause mortality, but few well-designed studies have examined the effects of depression on the full range of cardiovascular disease outcomes in type 2 diabetes. RESEARCH DESIGN AND METHODS A total of 2,053 participants in the ACCORD (Action to Control Cardiovascular Risk in Diabetes) Health-Related Quality of Life substudy completed the Patient Health Questionnaire (PHQ)-9 measure of depression symptoms at baseline and 12, 36, and 48 months. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) (95% CI) for the time-varying impact of depression on protocol-defined clinical outcomes with and without adjustment for demographic, trial-related, clinical, and behavioral variables. RESULTS In fully adjusted models, depression was not significantly related to the ACCORD primary composite outcome (cardiovascular death, nonfatal heart attack, or stroke) (HR 1.53 [95% CI 0.85–2.73]) or to the ACCORD microvascular composite outcome (0.93 [0.53–1.62]), but all-cause mortality was significantly increased both in those with PHQ-assessed probable major depression (2.24 [1.24–4.06]) and PHQ score of ?10 (1.84 [1.17–2.89]). The effect of depression on all-cause mortality was not related to previous cardiovascular events or to assignment to intensive or standard glycemia control. Probable major depression (by PHQ-9) had a borderline impact on the ACCORD macrovascular end point (1.42 [0.99–2.04]). CONCLUSIONS Depression increases the risk of all-cause mortality and may increase the risk of macrovascular events among adults with type 2 diabetes at high risk for cardiovascular events.

Sullivan, Mark D.; O'Connor, Patrick; Feeney, Patricia; Hire, Don; Simmons, Debra L.; Raisch, Dennis W.; Fine, Lawrence J.; Narayan, K.M. Venkat; Ali, Mohammad K.; Katon, Wayne J.

2012-01-01

314

Combining psychotherapy and antidepressants in the treatment of depression  

Microsoft Academic Search

Objective: To compare the efficacy of antidepressants with that of antidepressants plus psychotherapy (“combined therapy”) in the treatment of depression. Method: 6 month randomised clinical trial of antidepressants (N=84) and combined therapy (N=83) in ambulatory patients with Major Depression and a 17-item HDRS baseline score of at least 14 points. The antidepressant protocol provides for three successive steps in case

F de Jonghe; S Kool; G van Aalst; J Dekker; J Peen

2001-01-01

315

Detecting depression among adolescents in Santiago, Chile: sex differences  

PubMed Central

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.

2013-01-01

316

Traumatic Brain Injury and Depression. Comparative Effectiveness Review Number 25.  

National Technical Information Service (NTIS)

The prevalence of depression after traumatic brain injury (TBI) was approximately 30 percent across multiple time points up to and beyond a year. Based on structured clinical interviews, on average 27 percent met criteria for depression 3 to 6 months from...

F. T. Phibbs J. J. Eicken J. J. Seroogy J. N. McKoy M. L. McPheeters O. D. Guillamondegui P. T. Alexander R. N. Jerome S. A. Montgomery

2011-01-01

317

Prevalence of depression among memory clinic patients as measured by the Cornell Scale of Depression in Dementia.  

PubMed

Objectives: Depression in dementia is common, but the prevalence rates differ according to the populations studied and which diagnostic tools are being used. The aim of this study is to explore the prevalence of depression among patients referred to a memory clinic or an outpatient clinic as measured by the Cornell Scale of Depression in dementia (CSDD) and to investigate which factors are associated with depression. Method: The CSDD was completed for 1470 patients on their first visit to a memory clinic or an outpatient clinic. The prevalence of depression using three different cut-off points was calculated. Logistic regression and correlation analyses were performed. Results: Half of the patients had dementia. The mean CSDD was 6.7 (SD: 5.3) for the whole group, and 50.2% had a score above 5, whereas 37.5% had depression defined as a CSDD score above 7, and 14.1% had a score above 12. The mean scores were higher among those with dementia other than Alzheimer's disease, those with previous depression, and those with greater impairment in the activities of daily living (ADL). In the logistic regression analyses, younger age, ADL dysfunction, and previous depression were significantly associated with higher CSDD scores. Conclusion: We found that depressive symptoms are common among patients referred for a dementia assessment in specialist health care. The strongest factors associated with depressive symptoms were younger age, ADL impairment, and previous depression. PMID:23998196

Knapskog, Anne-Brita; Barca, Maria L; Engedal, Knut

2014-07-01

318

Ground freezing for containment of hazardous waste  

SciTech Connect

The freezing of ground for the containment of subsurface hazardous waste is a promising method that is environmentally friendly and offers a safe alternative to other methods of waste retention in many cases. The frozen soil method offers two concepts for retaining waste. One concept is to freeze the entire waste area into a solid block of frozen soil thus locking the waste in situ. For small areas where the contaminated soil does not include vessels that would rupture from frost action, this concept may be simpler to install. A second concept, of course, is to create a frozen soil barrier to confine the waste within prescribed unfrozen soil boundaries; initial research in this area was funded by EPA, Cincinnati, OH, and the Army Corps of Engineers. The paper discusses advantages and limitations, a case study from Oak Ridge, TN, and a mesh generation program that simulates the cryogenic technology.

Sayles, F.N.; Iskandar, I.K.

1998-07-01

319

Freeze-out parameters: lattice meets experiment.  

PubMed

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 us 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. PMID:23971565

Borsányi, S; Fodor, Z; Katz, S D; Krieg, S; Ratti, C; Szabó, K K

2013-08-01

320

Fundamentals of spray freezing of instant coffee  

Microsoft Academic Search

The freezing of single 2mm diameter droplets of coffee solution in cold moving air down to ?15°C has been studied for 10–50wt.% coffee solutions in a novel temperature monitoring apparatus and in a similar device installed within a nuclear magnetic resonance (NMR) spectrometer. Heat transfer measurements and modelling confirmed that droplet internal temperatures were almost uniform (low Biot number regime),

C. S. MacLeod; J. A. McKittrick; J. P. Hindmarsh; M. L. Johns; D. I. Wilson

2006-01-01

321

Drying a tuberculosis vaccine without freezing  

Microsoft Academic Search

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

Y.-L. Wong; Samantha Sampson; W. A. Germishuizen; Sunali Goonesekera; Giovanni Caponetti; Jerry Sadoff; B. R. Bloom; David Edwards

2007-01-01

322

Introduction: plant cold acclimation and freezing tolerance.  

PubMed

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

Hincha, Dirk K; Zuther, Ellen

2014-01-01

323

Atmospheric freeze drying assisted by power ultrasound  

NASA Astrophysics Data System (ADS)

Atmospheric freeze drying (AFD) is considered an alternative to vacuum freeze drying to keep the quality of fresh product. AFD allows continuous drying reducing fix and operating costs, but presents, as main disadvantage, a long drying time required. The application of power ultrasound (US) can accelerate AFD process. The main objective of the present study was to evaluate the application of power ultrasound to improve atmospheric freeze drying of carrot. For that purpose, AFD experiments were carried out with carrot cubes (10 mm side) at constant air velocity (2 ms-1), temperature (-10°C) and relative humidity (10%) with (20.5 kWm-3,USAFD) and without (AFD) ultrasonic application. A diffusion model was used in order to quantify the influence of US in drying kinetics. To evaluate the quality of dry products, rehydration capacity and textural properties were determined. The US application during AFD of carrot involved the increase of drying rate. The effective moisture diffusivity identified in USAFD was 73% higher than in AFD experiments. On the other hand, the rehydration capacity was higher in USAFD than in AFD and the hardness of dried samples did not show significant (p<0.05) differences. Therefore, US application during AFD significantly (p<0.05) sped-up the drying process preserving the quality properties of the dry product.

Santacatalina, J. V.; Cárcel, J. A.; Simal, S.; Garcia-Perez, J. V.; Mulet, A.

2012-12-01

324

Diabetes and depression.  

PubMed

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

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

2014-06-01

325

Depression and neurological disorders.  

PubMed

Depression is the most common psychiatric disorder in neurological disorders such as epilepsy, multiple sclerosis, stroke, and Parkinsons disease. It is associated with reduction of quality of life, functional impairment, and higher mortality. The diagnosis of depression in neurological disorders is difficult because of the overlapping symptoms. Neurological disorders are usually associated with sleep and appetite disturbances, fatigue, apathy, and lack of concentration, which is similar to those of depression. The etiology of depression with neurological disorders is unknown, but the interaction between biological, psychosocial, and neuropathological factors could be responsible for it. Few controlled trials have been carried out to investigate the efficacy of psychotherapeutic and pharmacological interventions in this population, and it seems that they are effective in improving depression, quality of life, and survival. Studies pertaining to prevention of depression in neurological disorders are promising. PMID:21048620

Bassiony, Medhat M

2009-07-01

326

Treatment-Resistant Depression  

Microsoft Academic Search

Our ability to treat depression has improved with the availability of receptor-specific and chemically diverse groups of antidepressants. Even now, most of the short-term studies indicate that about 20% of depressed patients remain resistant to treatment. Therefore, it is important to properly assess the treatment-resistant depressed (TRD) patients and to separate the truly refractory patients from those inadequately treated. Undiagnosed

Jambur Ananth

1998-01-01

327

Depression and attachment problems.  

PubMed Central

This study investigated the characteristics related to attachment of 42 depressed psychiatric patients and 42 non-depressed psychiatric controls. The depressed subjects demonstrated an anxious pattern of attachment, characterized by either intense care-seeking in relation to their attachment figure or angry withdrawal from their attachment figure when their desire for security was frustrated. The results are discussed in terms of Bowlby's attachment construct.

Pettem, O; West, M; Mahoney, A; Keller, A

1993-01-01

328

Major Depressive Disorder  

Microsoft Academic Search

Major depressive disorder or “unipolar depression” is a common condition likely related to several etiologies. Recent research\\u000a has focused on the biological underpinnings of major depressive disorder as well as treatment advances, involving both pharmacotherapy\\u000a and psychotherapy. In this chapter, the epidemiology, clinical picture, biological theories regarding etiology, clinical presentation\\u000a in primary care and mental health jhysettings, and treatment of

David L. Dunner

329

Neurobiology of Depression  

Microsoft Academic Search

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

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

2002-01-01

330

Epidemiology of depression  

Microsoft Academic Search

Review of the published literature produces 1-year prevalence rates for major depressive disorder DSM-III between 2.6 and 6.2%, for dysthymia between 2.3 and 3.7%, bipolar disorder 1.0–1.7%. Data from the prospective Zurich Study with four interviews over 10 years give relatively high 10-year prevalence rates for subjects from age 20 to 30 (14.4% major depression, 10.5% recurrent brief depression, 0.9%

J. Angst

1992-01-01

331

Depression-like deficits in rats improved by subchronic modafinil  

Microsoft Academic Search

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

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

2009-01-01

332

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

333

[Recurrent brief depressions].  

PubMed

Recurrent brief depression is a new diagnostical entity recently individualized among depressive disorders and characterized by repeated brief depressive episodes of a few days duration at least once a month over one year. The disorder generally of early onset seems to be present in 14.6% of the population up to 35 years and is associated with marked family and social disturbances as well as with a high rate of suicide attempts. The adequate treatment of recurrent brief depression has still to be defined and fluoxetine-type antidepressants appear devoid of efficacy. PMID:9453189

Ansseau, M

1997-11-01

334

Cognitive Aspects of Depression  

PubMed Central

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.

Joormann, Jutta; Gotlib, Ian H.

2012-01-01

335

Heart failure and depression.  

PubMed

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

Newhouse, Amy; Jiang, Wei

2014-04-01

336

Predictors of Persistence After a Positive Depression Screen Among Adolescents  

PubMed Central

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.

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

2012-01-01

337

Sudden Gains and Critical Sessions in Cognitive—Behavioral Therapy for Depression  

Microsoft Academic Search

In this study of cognitive—behavioral therapy for depression, many patients experienced large symptom improvements in a single between-sessions interval. These sudden gains' average magnitude was 11 Beck Depression Inventory points, accounting for 50% of these patients' total improvement. Patients who experienced sudden gains were less depressed than the other patients at posttreatment, and they remained so 18 months later. Substantial

Tony Z. Tang; Robert J. DeRubeis

2000-01-01

338

Sudden Gains and Critical Sessions in Cognitive–Behavioral Therapy for Depression  

Microsoft Academic Search

In this study of cognitive–behavioral therapy for depression, many patients experienced large symptom improvements in a single between-sessions interval. These sudden gains’ average magnitude was 11 Beck Depression Inventory points, accounting for 50% of these patients’ total improvement. Patients who experienced sudden gains were less depressed than the other patients at posttreatment, and they remained so 18 months later. Substantial

Tony Z. Tang; Robert J. DeRubeis

1999-01-01

339

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

ERIC Educational Resources Information Center

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…

Schick, Tom

340

“The top of my head came off?”: An interpretative phenomenological analysis of the experience of depression  

Microsoft Academic Search

This study explored what it is actually like to be depressed, that is, to capture the content and complexity of this experience from the view point of the sufferer. We present a case study using interpretative phenomenological analysis (IPA) of one man diagnosed with reactive depression. A semi-structured interview explored the experience of depression. The interview was transcribed and analysed

John Rhodes; Jonathan A. Smith

2010-01-01

341

Prevalence and correlates of depression symptoms at 10 years after heart transplantation: continuous attention required  

Microsoft Academic Search

This study investigates the presence and correlates of symptoms of depression at 5 and 10 years after heart transplantation, with particular attention given to patients showing symptoms at both time points. Prevalence of depression symptoms were studied in 41 patients, prospectively, at 5 and 10 years after heart transplantation. We examined potential correlates of depression symptoms (i.e. worse functional capacity,

Fabienne Dobbels; Sabina De Geest; Sandra Martin; Johan Van Cleemput; Walter Droogne; Johan Vanhaecke

2004-01-01

342

The Zurich study —A prospective epidemiological study of depressive, neurotic and psychosomatic syndromes  

Microsoft Academic Search

Summary How common and how significant are brief depressive episodes (BDE) lasting less than 2 weeks? The authors propose splitting the BDE into two groups: one occurring monthly over 1 year of observation, termed ‘recurrent brief depression’BD), and those occurring less frequently, labeled ‘recurrent brief depression’ BD). From a medical point of view, the RBD are a relevant group. Different

J. Angst; A. Dobler-Mikola

1985-01-01

343

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

PubMed

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

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

2010-05-01

344

Screening for depression in chronic hemodialysis patients: comparison of the Beck Depression Inventory, primary nurse, and nephrology team.  

PubMed

Depression in patients with end-state renal disease (ESRD) is both underdiagnosed and treated, which may contribute to an increase in morbidity and mortality. Efforts aimed at screening, diagnosing, and treating depression could potentially modify outcomes in this population. The purpose of this study was to compare the prevalence of depression, as measured by the Beck Depression Inventory (BDI-II), the primary nurse, and nephrology team, among a cohort of patients receiving chronic hemodialysis (HD). A secondary objective was to identify patient variables associated with depression. Patients were screened for depression at the same time point, using the BDI-II, the primary nurse and the nephrology team. Depression was defined as a BDI-II score > or =14. Agreement between the BDI-II score, nurse, and nephrology team assessment of depression was compared using a kappa score and receiver-operating characteristic (ROC) curves were generated. One hundred and twenty-four of an eligible 154 patients completed the study. Depression as measured by a BDI-II> or =14, the nurse and the team was diagnosed in 38.7%, 41.9%, and 24.2% of patients, respectively. With the BDI-II as the gold standard, the nurses' diagnosis of depression had an agreement of 74.6% vs. only 24.2% agreement with the nephrology team. A previous history of malignancy was the only variable associated with the diagnosis of depression. Depression is common among patients on HD, supporting the need for a routine depression-screening program. The primary dialysis nurse is in a key position to identify patients with depression and should be considered as an integral part of the nephrology team. PMID:16441825

Wilson, Barbara; Spittal, Joan; Heidenheim, Paul; Herman, Margaret; Leonard, Margaret; Johnston, Ann; Lindsay, Robert; Moist, Louise

2006-01-01

345

Depression in patients with chronic venous ulceration.  

PubMed

As leg ulcer research has generally focused on aspects of treatment, the psychosocial impact of leg ulceration remains understudied. This article reports the findings of a study exploring the prevalence of anxiety and depression in 190 patients with chronic venous ulceration across 9 Trusts in the northwest of England. The hospital anxiety and depression scale (HADS) was used to screen patients for the presence of anxiety and depression using a cut-off point of 9 for level of "caseness". A total of 52 (27%) people scored as depressed while 50 (26%) scored as anxious. The two symptoms which appeared to be associated with anxiety and depression were pain and odour, while there was no association found between living alone, mobility and exudate. These findings suggest that the focus of care needs to be redirected for many patients for whom cure is not an option, but who are left to live with a chronic wound. Furthermore, psychological factors, including depression, should be a focus in assessment and ongoing review of patients with leg ulceration. PMID:16835511

Jones, June; Barr, Wally; Robinson, Jude; Carlisle, Caroline

346

Counseling Interventions with Depressed Children.  

ERIC Educational Resources Information Center

Defines depression and anxiety in children and addresses assessment issues. Describes nine specific interventions within the home and school that have helped depressed children. Provides case example of depressed sixth grade boy. (ABL)

Downing, Jerry

1988-01-01

347

The role of solvation on the conformational change during repeated freezing–thawing treatment to an extremely dilute aqueous solution of poly(vinyl alcohol)  

Microsoft Academic Search

The effect of solvation–desolvation process on the conformational change of poly(vinyl alcohol) in an extremely dilute aqueous solution during the repeated freezing–thawing treatment was investigated by a differential refractometer. It was found that the hydrodynamic volume of PVA decreased regularly and smoothly with the number of freezing–thawing cycles treatment increasing, as the intra-molecular entanglement points made the polymer chain contract,

Hu Yang; Rongshi Cheng; Hongfeng Xie; Zhiliu Wang

2005-01-01

348

Postpartum Depression: An Overview.  

ERIC Educational Resources Information Center

Occurring in about 12 percent of postpartum women, postpartum depression has been focus of considerable research. Variables that have been correlated with postpartum depression range from biological causes, to lack of social support, to relationship with husband, to attributional styles, to psychodynamic explanations. There is need for more…

Albright, Angela

1993-01-01

349

Depression Begets Depression: Comparing the Predictive Utility of Depression and Anxiety Symptoms to Later Depression  

ERIC Educational Resources Information Center

Background: The high comorbidity between depressive and anxiety disorders, especially among females, has called into question the independence of these two symptom groups. It is possible that childhood anxiety typically precedes depression in girls. Comparing of the predictive utility of symptoms of anxiety with the predictive utility of symptoms…

Keenan, Kate; Feng, Xin; Hipwell, Alison; Klostermann, Susan

2009-01-01

350

Depression in the Workplace  

MedlinePLUS

... to depressive disorders and in 76% of those cases, the employee was female iii . In a study of First Chicago Corporations, depressive disorders accounted for more than half of all medical plan dollars paid for mental health problems. The amount for treatment of these claims ...

351

Alzheimer's Disease and Depression.  

ERIC Educational Resources Information Center

Reviews research on depression in Alzheimer's disease (AD). Discusses evidence suggesting that depression affects many AD patients and can have profound effects on patient long-term functioning and caregiver well-being. Notes that field is dominated by studies of prevalence, as opposed to studies of etiology, association with other aspects of…

Teri, Linda; Wagner, Amy

1992-01-01

352

[Psychotherapy of depression].  

PubMed

A distinct separation between a pathological grief reaction and "psychosomatic" depressive syndromes is suggested, which would offer the possibility of selecting a specific psychotherapeutic method. The so-called regrief therapy (Volkan) is recommended for the treatment of the pathological grief reaction and supportive and expressive psychoanalytical methods for the "psychosomatic" depressive syndromes. PMID:3984351

Schuster, P; Strotzka, H

1985-02-15

353

'I am not a depressed person': How identity conflict affects help-seeking rates for major depressive disorder  

PubMed Central

Background There is a significant treatment gap for patients with depression. A third of sufferers never seek help, and the vast majority of those who do only do so after considerable delay. Little is understood regarding poor help-seeking rates amongst people with depression, with existing research mainly focussed on the impact of barriers to treatment. The current study explored psychological factors affecting help-seeking behaviour in clinically depressed individuals. Methods Semi-structured interviews were conducted with 20 current or previously clinically depressed participants who either had or had not sought professional help. Thematic analysis was used to analyse results. Results The onset of depressive symptoms created conflict with participants’ identity and personal goals. Delays in seeking help were primarily attributed to the desire to protect identity and goals from the threat of depressive symptoms. Participants used avoidance strategies to reduce the perceived threat of depressive symptoms on identity. These strategies interfered with help-seeking. Help-seeking was only undertaken once participants reached a point of acceptance and began to make concessions in their identity and goals, at which time they reduced their use of avoidance. Conclusions Difficulties resolving conflict between identity and depressive symptoms may account for significant delays in seeking help for depression. The results have implications for predicting health behaviour and improving treatment uptake for depression, and may inform existing help-seeking models.

2012-01-01

354

Effects of Symptom Reduction and Psychotropic Medication on Cognitive Impairment in Depression  

Microsoft Academic Search

Background: Depression is related to cognitive performance. This follow-up study examines the influence of depression symptoms and psychopharmacological treatment on change in the cognitive performance of patients with depressive episodes over a 2-year period. Sampling and Methods: Sixty-two in- and outpatients with depression of varying severity (ICD-10: F31–F33) were examined in an open prospective naturalistic observational study with 3 points

K. Frasch; C. Bullacher; M. Jäger; R. Kilian; M. Rink; R. Wittek; T. Becker; N. U. Neumann

2009-01-01

355

Elderly and depression.  

PubMed

It is believed that it is 'normal' for the elderly per sons to become depressed and many cases aren't recognized and thus lead to untold misery for the sufferers and their families. We have found that majority of the clients under study were females belonging to low socio economic status, uneducated and unemployed. Majority of the clients had moderate depression (58%), And about 19% of them had severe depression. The problems related to subjective depressive feelings were investigated through a structured questionnaire surveyed among 100 elderly clients in Udhyava Village of Udupi district. We conclude that there is a significant relationship between family--friend relationships and depressive feelings of aged people. PMID:18341166

Devi, Elsa Sanatombi; Neenu, A; Anu, P; Rosemary, J; Anju, B; Dalphina, S; Divya, K Y; Sonia, J; Bindu, M; Anit, J N

2007-10-01

356

COGNITIVE DYSFUNCTION IN DEPRESSION  

PubMed Central

Cognitive Dysfunction' was assessed in 30patients diagnosed to have Major Depression (DSM III R), using the PCI memory scale and the Wechsler Adult Performance Intelligence Scale, form PR both of which have been developed and standardised in India. Depressed patients revealed marked impairment on tests of attention and concentration, and immediate and delayed recall on tests of memory (PCI); while tests of performance (WAPIS) revealed global impairment. This impairment reversed with recovery from depression. While improved test scores occured along with improvement in depression, there was no direct correlation between the two i.e. the degree of improvement in WAPIS/PGI total scores was not directly proportional to the degree of improvement in depression scores.

John, Sajiv; Kuruvilla, K.

1992-01-01

357

[Depression and physical illness].  

PubMed

Depression associated to a physical illness may be under-recognized or under-treated because of its diagnosis related difficulties and the trivialization of its presence in such a context. Now, this association contributes to physical illness' worsening, increased impairment, and may be responsible of care withdrawal, and even of suicide. The association between depression and physical illness may be a simple coincidence, or a psychological reaction to physical illness or else is the direct consequence of the somatic disease through biological disturbances or the iatrogenic effects of the disease treatment. It is also known, that depressive mood constitutes a significant risk factor for the development of various somatic disorders. Finally, a depression should be evoked when facing unexplained physical complaints. The entanglement between depression and physical illness needs to be particularly careful with prescriptions and especially an increased vigilance about drugs interactions. PMID:18506976

Hazen, Constance; Soudry, Yaël; Consoli, Silla M

2008-02-29

358

Depression and Bipolar Support Alliance  

MedlinePLUS

... Forces JOINT COMMISSION LAUNCHES EDUCATIONAL CAMPAIGN ON ADULT DEPRESSION Educational Brochure Provides Guidance on Recognizing and Treating Depression [PDF] TRAINING VETERANS DBSA Awarded VA Contract to ...

359

Core Depressive Symptoms In Depressed Cancer OutpatientsB  

PubMed Central

Objective: This study aimed to estimate the prevalence of core depressive symptoms among cancer outpatients diagnosed with depressive or adjustment disorders with depressed mood. We also aimed to detect potential differences between patient self-assessment and psychiatrist evaluation in classifying the severity of depression. Methods: Fifty-two outpatients diagnosed with solid tumor malignancy and depressive or adjustment disorder with depressed mood were assessed using the Hamilton Depression Rating Scale (HAMD-17) (and its shortened version the HAMD-7) and the Zung Self-Rating Depression Scale (ZSDS) (and its shortened version BZSDS). Results: Based on HAMD-7 results, the prevalence of moderate depression was low (7.7%); using the BZSDS moderate depression was absent. Mild depression was identified in 82.3% and 73% of our subjects using the HAMD-7 and the BZSDS, respectively. The strength of agreement between psychiatrist and patients’ self-evaluation for mild depression was “slight”, employing the original and the abbreviated versions of both scales. Conclusion: Our findings suggest that the prevalence of core depressive symptoms is very low in cancer patients diagnosed with depressive disorder. The lack of a strong agreement between psychiatrist and patient in classifying the severity of depression highlights the importance of factors such as well-being and functional status among depressed cancer patients in their self assessment of depression.

Pasquini, Massimo; Berardelli, Isabella; Cabra, Ambra; Maraone, Annalisa; Matteucci, Gabriella; Biondi, Massimo

2011-01-01

360

Depression in epilepsy  

PubMed Central

Objective: To estimate the prevalence of depression in persons with epilepsy (PWE) and the strength of association between these 2 conditions. Methods: The MEDLINE (1948–2012), EMBASE (1980–2012), and PsycINFO (1806–2012) databases, reference lists of retrieved articles, and conference abstracts were searched. Content experts were also consulted. Two independent reviewers screened abstracts and extracted data. For inclusion, studies were population-based, original research, and reported on epilepsy and depression. Estimates of depression prevalence among PWE and of the association between epilepsy and depression (estimated with reported odds ratios [ORs]) are provided. Results: Of 7,106 abstracts screened, 23 articles reported on 14 unique data sources. Nine studies reported on 29,891 PWE who had an overall prevalence of active (current or past-year) depression of 23.1% (95% confidence interval [CI] 20.6%–28.31%). Five of the 14 studies reported on 1,217,024 participants with an overall OR of active depression of 2.77 (95% CI 2.09–3.67) in PWE. For lifetime depression, 4 studies reported on 5,454 PWE, with an overall prevalence of 13.0% (95% CI 5.1–33.1), and 3 studies reported on 4,195 participants with an overall OR of 2.20 (95% CI 1.07–4.51) for PWE. Conclusions: Epilepsy was significantly associated with depression and depression was observed to be highly prevalent in PWE. These findings highlight the importance of proper identification and management of depression in PWE.

Fiest, Kirsten M.; Dykeman, Jonathan; Patten, Scott B.; Wiebe, Samuel; Kaplan, Gilaad G.; Maxwell, Colleen J.; Bulloch, Andrew G.M.

2013-01-01

361

Freeze Tolerant Radiator for an Advanced EMU  

NASA Technical Reports Server (NTRS)

During an Extravehicular Activity (EVA), the astronaut s metabolic heat and the heat produced by the Portable Life Support Unit (PLSS) must be rejected. This heat load is currently rejected by a sublimator, which vents up to eight pounds of water each EVA. However, for advanced space missions of the future, water venting to space needs to be minimized because resupply impacts from earth will be prohibitive. If this heat load could be radiated to space from the PLSS, which has enough surface area to radiate most of the heat, the amount of water now vented could be greatly reduced. Unfortunately, a radiator rejects heat at a relatively constant rate, but the astronauts generate a variable heat load depending on how hard they are working. Without a way to vary the heat removal rate, the astronaut would experience cold discomfort or even frostbite. A proven method allowing a radiator to be turned-down is to sequentially allow tubes that carry the heat transfer fluid to the radiator to freeze. A drawback of current freezable radiators using this method is that they are far to heavy for use on a PLSS, because they use heavy construction to prevent the tubes from bursting as they freeze and thaw. This creates the need for a large radiator to reject most of the heat but with a lightweight tube that doesn t burst as it freezes and thaws. The new freezable radiator for the Extravehicular Mobility Unit (EMU) has features to accommodate the expansion of the radiator fluid when it freezes, and still have the high tube to fin conductance needed to minimize the number and weight of the tubes. Radiator fluid candidates are water and a propylene glycol-water mixture. This design maintains all materials within their elastic limits so that large volume changes can be achieved without breaking the tube. This concept couples this elastic expansion with an extremely lightweight, extremely high conductivity carbon fiber fin that can carry the heat needed to thaw a frozen tube. By using most of the exposed surface area of the PLSS as a radiator, the system can reject about 75% of the highest heat load, and reduce the loss of water through sublimation by a factor of four. The proposed radiator and a small water tank can be no heavier than the current system.

Copeland, Robert J.; Elliott, Jeannine; Weislogel, Mark

2004-01-01

362

A remote controlled freeze corer for sampling unconsolidated surface sediments  

Microsoft Academic Search

A new coring device is presented which allows the recovery of loose watery surface sediments and the water\\/sediment interface\\u000a byin situ freezing, resulting in well preserved samples. The instrument consists of a tripod with adjustable legs, a hydraulic system,\\u000a an insulated thermos (with two electrical pumps), and a wedge-shaped freeze box. Alcohol chilled with dry ice is the freezing\\u000a agent.

A. F. Lotter; I. Renberg; H. Hansson; R. Stöckli; M. Sturm

1997-01-01

363

A remote controlled freeze corer for sampling unconsolidated surface sediments  

Microsoft Academic Search

A new coring device is presented which allows the recovery of loose watery surface sediments and\\u000athe water\\/sediment interface by in situ freezing, resulting in well preserved samples. The instrument\\u000aconsists of a tripod with adjustable legs, a hydraulic system, an insulated thermos (with two\\u000aelectrical pumps), and a wedge-shaped freeze box. Alcohol chilled with dry ice is the freezing

A. F. Lotter; I. Renberg; H. Hansson; R. Stöckli; M. Sturm

1997-01-01

364

Risk factors for depression in patients undergoing hematopoietic cell transplantation.  

PubMed

Despite the prevalence and known adverse impacts of depression after hematopoietic cell transplantation (HCT), little is known about the trajectory of depression occurring after HCT, or which pretransplantation risk factors might help predict new or worsening post-HCT depression. This secondary analysis evaluated the relationships between pre-HCT patient-reported outcomes and demographic characteristics and post-HCT depression. A total of 228 adult HCT patients were evaluated pre-HCT (T1) and again at 6 to 7 weeks post-HCT (T2), using touch-screen computers in the transplantation clinic during participation in a larger trial. Measures evaluated included the Symptom Distress Scale, the EORTC QLQ-C30 for quality of life, a single-item pain intensity question, and the Patient Health Questionnaire 9 for measurement of depression. At T1, rates of depression were quite low, with only 6% of participants reporting moderate or higher depression. At T2, however, the prevalence of moderate or higher depression was 31%. We observed a strong linear relationship in PHQ-9 scores between T1 and T2 (P < .0001). Depression score at T1 was a significant predictor of depression score at T2 (P = .03), as was poorer emotional function at T1 (P < .01). Our results indicate that post-HCT depression is common, even in patients with a low pre-HCT depression score. Frequent screening for symptoms of depression at critical time points, including 6 to 7 weeks post-HCT, are needed in this population, followed by referrals to supportive care as appropriate. PMID:24650679

Artherholt, Samantha B; Hong, Fangxin; Berry, Donna L; Fann, Jesse R

2014-07-01

365

Theory in Practice: Helping Providers Address Depression in Diabetes Care  

PubMed Central

Introduction A Continuing Education (CE) program based on the theory of planned behavior was designed to understand and improve health care providers’ practice patterns in screening, assessing, and treating and/or referring patients with diabetes for depression treatment. Methods Participants completed assessments of attitudes, confidence, intentions, and behaviors regarding depression management at three time points: immediately prior to the CE program (baseline), immediately after the CE program (posttest) and six-weeks after the CE program (follow-up). Results Ninety eight providers attended the CE program; 71 completed the baseline assessment; 66 completed the posttest assessment, and 37 completed the 6-week follow-up. Compared to baseline, at posttest providers reported significantly more favorable attitudes, fewer negative attitudes, greater confidence, and greater intention to address depression with their diabetes patients. At six weeks follow-up, there was a marginally significant increase in educating patients about depression, but no other depression management practices changed. Intention to change and confidence predicted some depression practice patterns at follow-up. Fewer barriers were a consistent predictor of depression practice patterns at follow-up. Discussion In the short-term, provider attitudes, confidence, and intentions to address depression with their patients improved. Intention, confidence, and especially barriers are important intervention targets. Lessons for Practice Depression is a common comorbidity of diabetes. Healthcare providers must be better prepared to manage depression in their diabetes patients. Educating health professionals is one approach to improving depression care. Healthcare systems must address barriers to providers’ efforts to manage depression. Continuing education programs should aim to enhance providers’ intentions, confidence, and skills to overcome barriers to addressing depression in clinical care.

Osborn, Chandra Y.; Kozak, Cindy; Wagner, Julie

2011-01-01

366

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

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

W. D. ZHUANG; T. W. EAGAR

367

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

Microsoft Academic Search

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

M. W. Woo; A. S. Mujumdar

2010-01-01

368

Viscoelastic analysis of interaction between freezing wall and outer shaft wall in freeze sinking  

Microsoft Academic Search

In order to reasonably determine the external load of outer freezing shaft wall, it is necessary to conduct interaction study between frozen soil wall and outer shaft wall. First, based on the characteristic of three-stage compressive deformation of foam board, a relational expression of such radial deformations as frozen soil wall, outer shaft wall, and foam board is established; then

Yan-sen Wang; Zhi-jiang Yang; Wei-hao Yang

2009-01-01

369

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

Microsoft Academic Search

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

S. M. Johnson; M. I. Gusman

1993-01-01

370

Design of a blood-freezing system for leukemia research  

NASA Technical Reports Server (NTRS)

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.

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

1978-01-01

371

Freezing and Melting, Precipitation Type, and Numerical Weather Prediction  

NSDL National Science Digital Library

This Webcast, Freezing and Melting, Precipitation Type, and Numerical Weather Prediction, is based on a COMET classroom presentation by Dr. Gary Lackmann at the 2nd MSC Winter Weather Course held in Boulder, Colorado on 22 February 2002. Dr. Lackmann reviews the basic thermodynamics of freezing and melting and how operational models represent these processes. He also touches upon the biases that occur in the models by looking at examples of melting snow aloft, melting snow at the surface, freezing aloft (ice pellets), and freezing rain. Dr. Lackmann is a faculty member in the Department of Marine, Earth, and Atmospheric Sciences at North Carolina State University.

Spangler, Tim

2002-01-01

372

A molecular dynamics study of freezing in a confined geometry  

NASA Technical Reports Server (NTRS)

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.

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

1992-01-01

373

A calorimeter to detect freezing in supercooled water droplets  

NASA Astrophysics Data System (ADS)

This apparatus suspends a 1 ?l water droplet on an ultraminiature thermistor and uses a Peltier cooling device to supercool the droplet. Electrical connections to the thermistor allow the temperature of the droplet to be constantly monitored, and they also permit direct electrical heating of the droplet after freezing has occurred. Deionized water droplets can be readily supercooled to temperatures of -20 °C before freezing, and repeated determinations of the freezing temperature for the same droplet are straightforward. The temperature characteristics of the phase change are very well defined, and the apparatus therefore permits many other investigations on the provocation of freezing in a supercooled droplet.

Harrison, R. G.; Lodge, B. N.

1998-11-01

374

Optical coherence tomography-based freeze-drying microscopy  

PubMed Central

A new type of freeze-drying microscope based upon time-domain optical coherence tomography is presented here (OCT-FDM). The microscope allows for real-time, in situ 3D imaging of pharmaceutical formulations in vials relevant for manufacturing processes with a lateral resolution of <7 ?m and an axial resolution of <5 ?m. Correlation of volumetric structural imaging with product temperature measured during the freeze-drying cycle allowed investigation of structural changes in the product and determination of the temperature at which the freeze-dried cake collapses. This critical temperature is the most important parameter in designing freeze-drying processes of pharmaceutical products.

Mujat, Mircea; Greco, Kristyn; Galbally-Kinney, Kristin L.; Hammer, Daniel X.; Ferguson, R. Daniel; Iftimia, Nicusor; Mulhall, Phillip; Sharma, Puneet; Pikal, Michael J.; Kessler, William J.

2011-01-01

375

Freezing efficiency of Silver Iodide, ATD and Kaolinite in the contact freezing mode  

NASA Astrophysics Data System (ADS)

The importance of heterogeneous ice nucleation via contact freezing is one of the open questions in the atmospheric science community. In our laboratory, we built the Collision Nucleation CHamber (CLINCH) (Ladino et al. 2011) in which falling cloud droplets can collide with aerosol particles. In this study, contact freezing experiments are conducted to investigate the ice nucleation ability of silver iodide (AgI), kaolinite and Arizona Test Dust (ATD). Silver iodide has been known for its ice nucleation ability since 1940s (Vonnegut 1947) while kaolinite is a clay mineral and known to be a moderate ice nucleus. ATD is a commercial dust sample used by many groups to compare different setups. In CLINCH, size selected aerosol particles collide with water droplets of 80 µm diameter. With the extension in chamber length it is possible to vary the interaction time of ice nuclei and the droplets. Our experiments are performed between -10 to -36 ºC for various concentrations of ice nuclei and different interaction times. The frozen fraction of the droplets is determined using the custom-made depolarization detector IODE (Nicolet et al., 2010). Depolarization of linearly polarized incident laser light is used to determine the ratio of frozen droplets to all droplets. Frozen fractions of the three particle types with different residence times from CLINCH will be presented in this study. The number of collisions between a single droplet and several aerosol particles can be calculated by accounting for the theoretical collision efficiency at the experimental conditions in order to obtain the freezing efficiency (frozen fraction/number of collisions). Nucleation efficiency is compared with other contact freezing studies and with immersion freezing

Nagare, Baban; Marcolli, Claudia; Stetzer, Olaf; Lohmann, Ulrike

2014-05-01

376

A Holistic Description of Immersion Freezing of Water and Aqueous Solution Droplets Using a Water Activity Based Model  

NASA Astrophysics Data System (ADS)

Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation in the atmosphere where it results in the glaciation of mixed-phase and cirrus clouds. Using a variety of IN types suspended in various aqueous solutions and pure water, we find that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, aw, which is the ratio of the vapor pressure of the solution and the saturation water vapor pressure under the same conditions and, in equilibrium, is equivalent to relative humidity (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, Jhet, to be uniquely expressed by T and aw, a result termed the aw based immersion freezing model (ABIFM). This method is independent of the nature of the solute, applicable for pure water droplet freezing which is significant for mixed-phase cloud formation, and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing capable of predicting of freezing temperatures, Jhet, frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas and cooling rates of droplets containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as IN surface area increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The experimental data implicitly questions the common notion that one active site initiates the formation of an ice embryo leading to the crystallization of the aqueous phase. The log10(Jhet) values for the various IN types derived exclusively by T and aw, provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total IN surface area, and cloud activation timescales typical of atmospheric conditions. Lastly, we demonstrate that ABIFM can be used to derive frozen fractions of droplets and ice particle production for atmospheric models of cirrus and mixed phase cloud conditions.

Knopf, D. A.; Alpert, P. A.

2013-12-01

377

Freeze-fracture scanning electron microscopy and comparative freeze-etching study of parallel fiber-Purkinje spine synapses of vertebrate cerebellar cortex.  

PubMed

The three dimensional surface morphology, topographical arrangement and intramembrane features of parallel fiber-Purkinje spine synapses of teleost fishes and Swiss albino mice cerebellar cortex have been complementarily studied with the scanning electron microscope (SEM) using the freeze-fracture method and with transmission electron microscope (TEM) by means of freeze-etching replica and thin-sectioning techniques. The SEM fractographs revealed for the first time the outer surface morphology of non-synaptic segments and synaptic varicosities of parallel fibers, which showed clusters of spheroidal synaptic vesicles joined by an amorphous substance. Freeze-etching preparations showed an 'en face' view of P face parallel fiber varicosity (presynaptic P face) characterized by a depressed synaptic active zone with exocytotic vesicle sites, round IMPs (7.5-15 nm), and rod particles (38.5-53 nm in length). Conversely the presynaptic E face exhibited a smooth surface, randomly distributed pits and very low density distribution of round IMPs. The P face of Purkinje spine membrane (postsynaptic P face) showed high density distribution of round or ovoid IMPs, 8-18.5 nm in diameter, and rod IMPs up to 79.2 nm in length. IMPs were also observed beneath the postsynaptic membrane (subsynaptic IMPs) corresponding to the localization of postsynaptic density. The E face of Purkinje spine membrane (postsynaptic E face) showed aggregation of round IMPs, 5.6-17.4 nm in diameter, at the synaptic active zone. Some of these IMPs, particularly the large ones, may morphologically represent the glutamate-receptor ion channels complex. The subsynaptic IMPs may correspond to protein kinases. Granular material and fine filaments were observed in the postsynaptic density. A better insight into the topographical relationship between pre- and postsynaptic structures was obtained of flat and invaginated spine synapses and beside a more realistic view of their glial ensheathment. The SEM fractographs and freeze-etching images were compared with corresponding TEM thin sections for orientation and proper identification of pre- and postsynaptic structures. PMID:2337890

Castejón, O J

1990-04-01

378

Depressive thinking and depression: relations with personality and social resources.  

PubMed

The mechanisms by which social supports and personality variables may buffer against psychopathology are not well understood. We studied depression, depressive cognitions, social supports, and self-esteem in a sample of 68 spouse-caregivers of patients with Alzheimer's Disease in an attempt to identify possible buffering mechanisms of the latter two variables. Specifically, we hypothesized that the well-known relation of depressive cognitions to depression would vary as a function of satisfaction with social supports and with level of self-esteem. Hierarchical multiple regression analyses conducted to predict depression revealed significant and independent main effects for depressive cognitions (p less than .01), social supports (p less than .025), and self-esteem (p less than .001), with depressive cognitions associated with higher depression and the other two variables associated with reduced depression (R2 = .53 for the three main effects). In addition, the relation of depressive cognitions with depression varied substantially depending on the level of social supports (p less than .01); caregivers with high levels of depressive cognitions had high levels of depression only if social supports were low (R2 = .61 including interaction). Self-esteem and depressive cognitions showed a similar interaction, but it failed to reach significance. Analyses to determine whether self-esteem and social supports were directly associated with lower depressive cognitive activity yielded a main effect for self-esteem only (p less than .03). Thus, whereas social supports and self-esteem were directly associated with lower depression, only the social supports variable was further associated with reduced depression because it apparently buffered the impact of depressive thinking. Self-esteem was also indirectly associated with lower depression via its relation with lower depressive thinking. Implications of our results for cognitive theories of depression and for the psychosocial mechanisms of stress buffering are discussed. PMID:3585698

Pagel, M; Becker, J

1987-05-01

379

Fundamental Boiling and RP-1 Freezing Experiments  

NASA Technical Reports Server (NTRS)

This paper describes results from experiments performed to help understand certain aspects of the MC-1 engine prestart thermal conditioning procedure. The procedure was constrained by the fact that the engine must chill long enough to get quality LOX at the LOX pump inlet but must be short enough to prevent freezing of RP-1 in the fuel pump. A chill test of an MC-1 LOX impeller was performed in LN2 to obtain data on film boiling, transition boiling and impeller temperature histories. The transition boiling data was important to the chill time so a subsequent experiment was performed chilling simple steel plates in LOX to obtain similar data for LOX. To address the fuel freezing concern, two experiments were performed. First, fuel was frozen in a tray and its physical characteristics were observed and temperatures of the fuel were measured. The result was physical characteristics as a function of temperature. Second was an attempt to measure the frozen thickness of RP-1 on a cold wall submerged in warm RP-1 and to develop a method for calculating that thickness for other conditions.

Goode, Brian; Turner, Larry D. (Technical Monitor)

2001-01-01

380

Lesbians' constructions of depression.  

PubMed

Lesbians are a marginalized group of women living in a heteronormative society. This study describes lesbians' subjective experiences of depression, and identifies the ways that dominant and alternative discourses shaped their understandings of depression and sexuality. Twelve self-identified lesbians participated in up to three in-depth interviews conducted over a 9-month period. Thematic analysis led to themes that explicated their physical and emotional descriptions of depression; identified troubled interpersonal relationships as a primary source of depression; and discussed the means implemented to cope with depression, including taking medication, engaging in therapy, developing social support networks, and discovering their own spirituality. Depression and sexuality were understood within the framework of the dominant discourses of (1) medical model, (2) dysfunctional family, and (3) organized religion; and the alternative discourses of (1) lesbian identity, (2) alternative families, and (3) spirituality. Nurses in clinical practice can assist depressed lesbian clients by bolstering explorations of spirituality and the development of strong support networks within the lesbian and gay communities. Politically, institutionalized heteronormativity must be attacked at every level. PMID:19350435

Barnard, Amy

2009-05-01

381

Lesbians' Constructions of Depression  

PubMed Central

Lesbians are a marginalized group of women living in a heteronormative society. This study describes lesbians’ subjective experiences of depression, and identifies the ways that dominant and alternative discourses shaped their understandings of depression and sexuality. Twelve self-identified lesbians participated in up to three in-depth interviews conducted over a nine month period. Thematic analysis led to themes that explicated their physical and emotional descriptions of depression; identified troubled interpersonal relationships as a primary source of depression; and the means implemented to cope with depression, including taking medication, engagement in therapy, developing social support networks, and discovering their own spirituality. Depression and sexuality were understood within the framework of the dominant discourses of (1) medical model (2) dysfunctional family and (3) organized religion; and the alternative discourses of (1) lesbian identity, (2) alternative families and (3) spirituality. Nurses in clinical practice can assist depressed lesbians clients by bolstering explorations of spirituality and the development of strong support networks within the lesbian and gay communities. Politically, institutionalized heteronormativity must be attacked at every level.

Barnard, Amy

2009-01-01

382

Age and depression.  

PubMed

In this study, the relationship between age and depression is analyzed, looking for effects of maturity, decline, life-cycle stage, survival, and historical trend. The data are from a 1990 sample of 2,031 U.S. adults and a 1985 sample of 809 Illinois adults. The results show that depression reaches its lowest level in the middle aged, at about age 45. The fall of depression in early adulthood and rise in late life mostly reflects life-cycle gains and losses in marriage, employment, and economic well-being. Depression reaches its highest level in adults 80 years old or older, because physical dysfunction and low personal control add to personal and status losses. Malaise from poor health does not create a spurious rise of measured depression in late adulthood. However, some of the differences among age groups in depression reflect higher education in younger generations, and some reflect different rates of survival across demographic groups that also vary in their levels of depression. PMID:1401846

Mirowsky, J; Ross, C E

1992-09-01

383

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

PubMed

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

Patrykiejew, A; Soko?owski, S

2010-01-01

384

Depression and Insulin Resistance  

PubMed Central

OBJECTIVE To examine the association between depressive disorder and insulin resistance in a sample of young adults using the Composite International Diagnostic Interview to ascertain depression status. RESEARCH DESIGN AND METHODS Cross-sectional data were collected from 1,732 participants aged between 26 and 36 years. Insulin resistance was derived from blood chemistry measures of fasting insulin and glucose using the homeostasis model assessment method. Those identified with mild, moderate, or severe depression were classified as having depressive disorder. RESULTS The 12-month prevalence of depressive disorder was 5.4% among men and 11.7% among women. In unadjusted models mean insulin resistance was 17.2% (95% CI 0.7–36.0%, P = 0.04) higher in men and 11.4% (1.5–22.0%, P = 0.02) higher in women with depressive disorder. After adjustment for behavioral and dietary factors, the increased level of insulin resistance associated with depressive disorder was 13.2% (?3.1 to 32.3%, P = 0.12) in men and 6.1% (?4.1 to 17.4%, P = 0.25) in women. Waist circumference was identified as a mediator in the relationship between depression and insulin resistance, reducing the ? coefficient in the fully adjusted models in men by 38% and in women by 42%. CONCLUSIONS A positive association was found between depressive disorder and insulin resistance in this population-based sample of young adult men and women. The association seemed to be mediated partially by waist circumference.

Pearson, Sue; Schmidt, Mike; Patton, George; Dwyer, Terry; Blizzard, Leigh; Otahal, Petr; Venn, Alison

2010-01-01

385

Effect of long-term freezing and freeze-thaw cycles on indigenous and inoculated microorganisms in dewatered blackwater.  

PubMed

Wastewater treatment in many Arctic regions is inadequate, even nonexisting. Natural freezing of wastewater in those areas may be beneficial for reduction of microorganisms. The aim of this study was to investigate the effect of long-term freezing, and repeated freezing and thawing, on indigenous coliforms, fecal streptococci, and antibiotic-resistant (AR) bacteria, and inoculated Salmonella Enteriditis and E. coli bacteriophage ?X174 in dewatered blackwater. At the end of the long-term freezing experiment (10 months), an MPN recovery study was done, including the microbial groups that had shown the largest reduction, using tryptone soy broth at incubation temperatures of 10 and 20 °C overnight for the coliforms and AR bacteria, and buffered peptone water at incubation temperature of 37 °C for 18-20 h for Salmonella. Fecal streptococci were more resistant to long-term freezing than the coliform group. Total number of AR bacteria decreased slowly but constantly over the 10-month freezing period. Salmonella rapidly decreased and were nondetectable within a week but exhibited some recovery after 10 months of freezing, whereas limited or no recovery of coliforms and AR-bacteria was detected. Bacteriophages showed limited reduction during the long-term freezing. Repeated freezing and thawing increased the reduction of all tested microbial groups markedly. PMID:23113759

Gunnarsdóttir, Ragnhildur; Müller, Karoline; Jensen, Pernille Erland; Jenssen, Petter Deinboll; Villumsen, Arne

2012-11-20

386

Increased spring freezing vulnerability for alpine shrubs under early snowmelt.  

PubMed

Alpine dwarf shrub communities are phenologically linked with snowmelt timing, so early spring exposure may increase risk of freezing damage during early development, and consequently reduce seasonal growth. We examined whether environmental factors (duration of snow cover, elevation) influenced size and the vulnerability of shrubs to spring freezing along elevational gradients and snow microhabitats by modelling the past frequency of spring freezing events. We sampled biomass and measured the size of Salix herbacea, Vaccinium myrtillus, Vaccinium uliginosum and Loiseleuria procumbens in late spring. Leaves were exposed to freezing temperatures to determine the temperature at which 50 % of specimens are killed for each species and sampling site. By linking site snowmelt and temperatures to long-term climate measurements, we extrapolated the frequency of spring freezing events at each elevation, snow microhabitat and per species over 37 years. Snowmelt timing was significantly driven by microhabitat effects, but was independent of elevation. Shrub growth was neither enhanced nor reduced by earlier snowmelt, but decreased with elevation. Freezing resistance was strongly species dependent, and did not differ along the elevation or snowmelt gradient. Microclimate extrapolation suggested that potentially lethal freezing events (in May and June) occurred for three of the four species examined. Freezing events never occurred on late snow beds, and increased in frequency with earlier snowmelt and higher elevation. Extrapolated freezing events showed a slight, non-significant increase over the 37-year record. We suggest that earlier snowmelt does not enhance growth in four dominant alpine shrubs, but increases the risk of lethal spring freezing exposure for less freezing-resistant species. PMID:24435708

Wheeler, J A; Hoch, G; Cortés, A J; Sedlacek, J; Wipf, S; Rixen, C

2014-05-01

387

Depressive symptoms amongst asthmatic children's caregivers.  

PubMed

We wanted to find out, whether the number of depressive symptoms is higher amongst asthmatic children's caregivers, compared to international data, to the Hungarian population average, and to parents of children with chronic renal disease. Are these depressive symptoms connected to the children's psychological status, asthma severity or current asthma symptoms? One-hundred and eight, 7- to 17-yr-old asthmatic children were enrolled, who have been treated at the Semmelweis University, First Department of Pediatrics. Children were suffering from asthma for at least 1 yr, with a median of 8 yr (1-16 yr), they started to develop asthmatic symptoms between the age of 0.5-14 yr (median: 3 yr). We also identified 27 children with chronic renal diseases and their caregivers, who functioned as a control group. Children were asked to complete the Hungarian-validated versions of the Child Depression Inventory, the Spielberger State Anxiety Inventory for Children and the Juniper Pediatric Asthma Quality of Life Questionnaire. Asthma severity and current symptoms were also documented, 56% had no symptoms on the preceding week. Caregivers were asked to complete the Hungarian versions of the Beck Depression Inventory (BDI) short form, the Spielberger Anxiety Inventory and the Juniper Pediatric Asthma Caregivers' Quality of Life Questionnaire. Caregivers of asthmatic children had significantly more depressive symptoms (7.73 +/- 6.69 s.d.) than the age-specific normal population (p < 0.01). Caregivers of renal patients also experience more depressive symptoms (9.61 +/- 7.43 s.d.) than their healthy peers, but difference between the two chronic diseases' group did not prove to be significant. Asthmatic children's caregivers who scored more points on the BDI than the population average suffer from more anxiety symptoms, but their quality of life is not worse than the caregivers' with less depressive points. Depressive symptoms were neither connected to the children's psychological and asthmatic symptoms nor quality of life. Amongst caregivers of asthmatic children, at least mild depressive symptoms were represented amongst 39% of men and 33% of women. Gender difference was not significant, despite observations in the normal Hungarian population. Amongst caregivers of renal patients, depressive symptoms were represented in 14% of men and 50% of women. Gender difference was significant. (p = 0.05). Significant difference was observed between male asthmatic and renal caregivers, albeit difference was not significant between the female groups. No difference was found in depressive symptoms according to caregivers' level of education. Caregivers of children with asthma have more depressive symptoms than the average Hungarian population, but their results do not differ from caregivers taking care of children with chronic renal diseases. Caregivers of asthmatic children having at least mild depressive symptoms tend to have higher anxiety symptoms as well. Up to date, childhood chronic disease management and long-term care should also focus on parental psychology, mainly on depression and anxiety, as prevalence is higher than in the average population. PMID:19744221

Szabó, Alexandra; Mezei, Györgyi; Kovári, Eva; Cserháti, Endre

2010-06-01

388

Hippocampal volume in geriatric depression  

Microsoft Academic Search

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

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

389

Heterogeneous freezing of ammonium sulfate and sodium chloride solutions by long chain alcohols  

NASA Astrophysics Data System (ADS)

High molecular weight organic compounds emitted during biomass burning can be transported to high altitudes where they may affect ice processes through heterogeneous nucleation. We show that freezing of solutions of ammonium sulfate and sodium chloride catalyzed by long chain alcohols is roughly consistent with the hypothesis that the water activity at the mean freezing temperature is a constant offset from the water activity at the melting point of the solution, though films of the longer chain alcohols may undergo structural changes at higher salt concentrations which cause a deviation from the constant offset. The heterogeneous nucleation rate coefficient, averaged over all solutions, alcohols, and droplet sizes is 6.0 × 104 +/- 4.0 × 104 cm-2 s-1, with no dependence on any of those parameters.

Cantrell, Will; Robinson, Carly

2006-04-01

390

Frost action of freezing ground surrounding underground storage of a cold liquid  

NASA Astrophysics Data System (ADS)

A small tank in the shape of a cylinder 80 cm in diameter and 50 cm in depth was placed in a basin, filled with a silty soil, of the frost test field in Tomakomai, Hokkaido Japan, with its top at the same level as the ground surface in the basin. The double wall (two steel sheets 10 cm apart) constituted the exterior of the side and bottom. As a cold liquid at temperature of -23 C was poured inside the gap of the double wall and circulated, the soil around the tank began to freeze sideways and downwards from the tank. Studies made are as follows: (1) the progress of the freezing front was measured and preestimated; (2) frost heaving characters of the tank and the ground surface around it were observed; (3) soil water migration was calculated by measuring moisture tensions at several points within the soil; (4) soil pressure acting on the tank was measured.

Kinosita, S.; Fukuda, M.; Ishizaki, T.; Yamamoto, H.

391

Freezing of polar stratospheric clouds in orographically induced strong warming events  

NASA Astrophysics Data System (ADS)

Results from laboratory experiments and microphysical modeling are presented that suggest a potential freezing nucleation mechanism for polar stratospheric cloud (PSC) particles above the water ice frost point (Tice). The mechanism requires very high HNO3 concentrations of about 58 wt% in the droplets, and leads to the freezing of nitric acid dihydrate (NAD) in a highly selective manner in the smallest droplets of an ensemble. In the stratosphere such liquid compositions are predicted to occur in aerosol droplets which are warmed adiabatically with rates of about +150 K/h from below 190 K to 194 K. Such rapid temperature changes have been observed in mountain leewaves that occur frequently in the stratosphere, clearly demonstrating the need for a stratospheric gravity wave climatology.

Tsias, A.; Prenni, A. J.; Carslaw, K. S.; Onasch, T. P.; Luo, B. P.; Tolbert, M. A.; Peter, Th.

1997-09-01

392

Freezing of a two-dimensional fluid into a crystalline phase: density functional approach.  

PubMed

A free-energy functional for a crystal proposed by Singh and Singh [Europhys. Lett. 88, 16005 (2009)] which contains both the symmetry conserved and symmetry broken parts of the direct pair correlation function has been used to investigate the crystallization of a two-dimensional fluid. The results found for fluids interacting via the inverse power potential u(r)=?(?/r)(n) for n=3,6, and 12 are in good agreement with experimental and simulation results. The contribution made by the symmetry broken part to the grand thermodynamic potential at the freezing point is found to increase with the softness of the potential. Our results explain why the Ramakrishnan-Yussouff [Phys. Rev. B 19, 2775 (1979)] free-energy functional gave good account of freezing transitions of hard-core potentials but failed for potentials that have soft core and/or attractive tail. PMID:23410333

Jaiswal, Anubha; Singh, Swarn L; Singh, Yashwant

2013-01-01

393

Rational design of an influenza subunit vaccine powder with sugar glass technology: Preventing conformational changes of haemagglutinin during freezing and freeze-drying  

Microsoft Academic Search

The development of a stable influenza subunit vaccine in the dry state was investigated. The influence of various carbohydrates, buffer types and freezing rates on the integrity of haemagglutinin after freeze-thawing or freeze-drying was investigated with a range of analytical and immunological methods. The use of fast freezing, Hepes buffer and carbohydrates (trehalose, inulin or dextran) as cryo- and lyoprotectants

J. P. Amorij; J. Meulenaar; W. L. J. Hinrichs; T. Stegmann; A. Huckriede; F. Coenen; H. W. Frijlink

2007-01-01

394

Depression, Dementia, and Delirium  

Microsoft Academic Search

Upon completion of the chapter, the student will be able to:\\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a State the epidemiology of depression, dementia, and delirium in older adults.\\u000a \\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a Describe the risk factors for the development of depression, dementia, and delirium.\\u000a \\u000a \\u000a \\u000a \\u000a 3. \\u000a \\u000a Understand the diagnostic workup of depression, dementia, and delirium.\\u000a \\u000a \\u000a \\u000a \\u000a 4. \\u000a \\u000a Develop a rational management plan for persons with depression, dementia, or delirium.

Rainier P. Soriano

395

Depression and Headaches  

MedlinePLUS

... a persistent and vague headache, for which no organic cause can be determined. For the patient, the ... develop bodily symptoms, and conversely people with painful organic diseases tend to become depressed. It should be ...

396

[Depression and circadian rhythm].  

PubMed

Adverse changes in circadian rhythms are an integral part of the clinical features of endogenous depression, and particularly of seasonal depression. Alongside twenty-four variations in the major symptoms, these forms of depression can be characterised psychometrically, physiologically and biologically. The most classical adverse changes are amplitude modifications, fluctuations and periodicity of the hormonal secretory rhythms. Pathophysiological and psychopathological models have been proposed to combat these abnormalities. The leading models include free course, phase advance (or instability) and hypnic models, or those based on disturbances of the internal clock. The main psychopathological models are those of endokinesis and psychosocial desynchronisation. The therapeutic applications of the pathophysiological models use manipulation of the wake-sleep cycle, phototherapy and melatonin and its derivatives : those of the psychopathological models used time-space management and development of resynchronisation capacities. The question determining whether these adverse changes are a cause or effect of depressive behaviour is unresolved. PMID:19268174

Azorin, J M; Kaladjian, A

2009-01-01

397

Depression and Pregnancy  

MedlinePLUS

... psychotherapy and/or medications. I have depression and am planning on getting pregnant. Is there anything I ... sad and have so little energy that I am having trouble going to my prenatal doctor’s appointments. ...

398

Depression and College Students  

MedlinePLUS

... campus suicide or crisis hotline Call the National Suicide Prevention Lifeline's toll-free, 24-hour hotline at 1- ... college students: results from the American Foundation for Suicide Prevention College Screening Project at Emory University. Depress Anxiety . ...

399

Suicide and Depression  

MedlinePLUS

Suicide and Depression Q&A Why do people kill themselves? Unfortunately, there is no simple answer to ... does not become an option. Do people attempt suicide to prove something or to get sympathy? No. ...

400

Depression and Osteoporosis  

MedlinePLUS

... Study of Osteoporotic Fractures Research Group. Archives of Internal Medicine . 1999 Mar 8; 159(5):484–90. 5. ... mass in premenopausal women with depression. Archives of Internal Medicine . 2007 Nov 26; 167(21):2329–36. 6. ...

401

Classification of depressive disorders.  

PubMed

The classification of depression is well established in major diagnostic systems and operational definitions now make the diagnosis of depression reasonably reliable. However, classification and diagnosis continue to be based on clinical presentation and course and are not currently informed by aetiological or pathophysiological considerations. It is still unclear, for example, whether or not categories such as melancholic depression represent distinct subforms of illness or whether a dimensional classification based on severity can capture clinical presentation adequately and more economically. Despite these caveats, there is some evidence that distinctions between various subforms of depression can predict treatment response and this can be useful for clinical practice as well as guiding research strategies. PMID:22923074

Cowen, Phillip J

2013-01-01

402

Stopping biological time: The freezing of living cells  

SciTech Connect

The fundamental physical-chemical events that occur during the freezing and thawing of cells are outlined and the manner in which cell permeability determines the response of the cell to freezing is discussed both in terms of physical response and in terms of survival. 40 refs., 12 figs.

Mazur, P.

1987-01-01

403

Heat of Freezing and Melting of Sea Ice.  

National Technical Information Service (NTIS)

Computations are presented which show that the latent heat of freezing ice in equilibrium with sea water is less than that associated with freezing pure water at 0C. The difference is due primarily to a temperature effect that is opposed to some extent by...

D. Anderson

1966-01-01

404

Evaluation of Human Sperm Function After Repeated Freezing and Thawing  

Microsoft Academic Search

Sperm storage via freezing has been useful for men who have difficulty masturbating during assisted reproductive tech- nology (ART) programs and before impotency caused by chemo- therapy, vasectomy, and other procedures. Studies were undertaken to evaluate the extent of cryoinjury to sperm after repeated freezing and thawing. The results showed that normozoospermic and oligo- zoospermic sperm survived after 3 repeated

ENOKA BANDULARATNE; ARIFF BONGSO

2002-01-01

405

Industrial applications of freeze concentration technology: Final report  

SciTech Connect

Often more energy-efficient than the separation technologies now in industrial use, freeze concentration techniques also offer advantages in product purity and quality. This applications analysis estimates that widespread adoption of freeze concentration could produce significant national energy savings, along with increasing baseload electricity consumption.

Barron, T.S.; Heist, J.A.; Hunt, K.M.; Wrobel, P.J.

1987-06-01

406

Free(z)ing Degrees of Freedom in Skill Acquisition  

Microsoft Academic Search

This study reports an empirical investigation into Bernstein's (1967) ideas that in the early stages of the acquisition of a movement skill the coordination problem is reduced by an initial freezing out of degrees of freedom, followed later in the learning process by the release of these degrees of freedom and their incorporation into a dynamic, controllable system. “Freezing” degrees

Beatrix Vereijken; Richard E. A. van Emmerik; H. T. A. Whiting; Karl M. Newell

1992-01-01

407

SFT: a consistent checkpointing algorithm with shorter freezing time  

Microsoft Academic Search

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

Xiaohui Wei; Jiubin Ju

1998-01-01

408

A multilayer freezer for freeze concentration of liquid milk  

Microsoft Academic Search

Over the past few decades, much progress has been made in the development of freeze concentration technology, and commercial freeze concentration plants have been established around the world. However, high costs still limit its use in many potential applications.A continuous, multilayer freezer was designed, constructed, and operated under different conditions. This process used a series of chambers, mounted as layers

Zhonglai Zhang; Richard W. Hartel

1996-01-01

409

Volume-Restricted Freezing of Living Cells and Tissues.  

National Technical Information Service (NTIS)

The effect of constant-volume freezing on the survival of red blood cells in diluted rabbit blood and of Artemia Salina (brine shrimp) in dimethyl sulfoxide (DMSO)-saline solution was examined. Constant-volume freezing significantly improved red-blood-cel...

S. D. Engstrom Y. E. Chu W. F. Sung M. S. Giroux

1977-01-01

410

Depression and obesity  

Microsoft Academic Search

The prevalence of depression (10%) and overweight (65%) indicates that there is a probability that they will co-occur, but are they functionally related? This report used the moderator\\/mediator distinction to approach this question. Moderators, such as severity of depression, severity of obesity, gender, socioeconomic status (SES), gene-by-environment interactions and childhood experiences, specify for whom and under what conditions effects of

Albert J Stunkard; Myles S Faith; Kelly C Allison

2003-01-01

411

ADHD and comorbid depression  

Microsoft Academic Search

Attention-deficit\\/hyperactivity disorder (ADHD) is prevalent, chronic, and often comorbid with other disorders. This article\\u000a reviews the literature on ADHD and comorbid major depressive disorder from childhood through adolescence and adulthood. We\\u000a also report findings from a study we conducted that examined the prevalence of ADHD and comorbid major depression in adults.\\u000a Diagnostic history data were analyzed in 524 adults (308

Lucy Cumyn; Lisa French; Lily Hechtman

2009-01-01

412

Rating Scales for Depression  

Microsoft Academic Search

\\u000a Over the past few decades, a number of clinician-rated and patient-rated instruments have been developed as primary efficacy\\u000a measures in depression clinical trials. All those scales have relative strengths and weaknesses and some of them have been\\u000a more successful than others, and have become the gold standards for depression clinical research. With all these measures\\u000a available and with the evidence

Cristina Cusin; Huaiyu Yang; Albert Yeung; Maurizio Fava

413

Depression and Postpartum Disorders  

Microsoft Academic Search

\\u000a In the first part of this chapter, an overview of prevalence and burden of depression in women across the lifespan will be\\u000a presented, as well as biopsychosocial etiological theories and a brief review of service use and treatment issues. The second\\u000a part of the chapter will focus specifically on prevalence, clinical, and health care use issues related to depression occurring

Heather A. Flynn

414

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

Microsoft Academic Search

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

DAVID K. WELLISCH; NANGEL M. LINDBERG

2001-01-01

415

Emerging from Depression: Treatment of Adolescent Depression Using the Major Treatment Models of Adult Depression.  

ERIC Educational Resources Information Center

Noting that adolescents who commit suicide are often clinically depressed, this paper examines various approaches in the treatment of depression. Major treatment models of adult depression, which can be directly applied to the treatment of the depressed adolescent, are described. Major treatment models and selected research studies are reviewed in…

Long, Kathleen M.

416

STEFINS: a steel freezing integral simulation program  

SciTech Connect

STEFINS (STEel Freezing INtegral Simulation) is a computer program for the calculation of the rate of solidification of molten steel on solid steel. Such computations arize when investigating core melt accidents in fast reactors. In principle this problem involves a coupled two-dimensional thermal and hydraulic approach. However, by physically reasonable assumptions a decoupled approach has been developed. The transient solidification of molten steel on a cold wall is solved in the direction normal to the molten steel flow and independent from the solution for the molten steel temperature and Nusselt number along the direction of flow. The solutions to the applicable energy equations have been programmed in cylindrical and slab geometries. Internal gamma heating of steel is included.

Frank, M.V.

1980-09-01

417

Freezing D2O clay gels.  

PubMed

To obtain the T1 surface value in smectites/D2O diluted suspensions or gels, as was obtained on a monolayer deuterated clay, we freeze them. The broad Pake's doublets similar to ice doublets and with the same T1 show that we can separate frozen from unfrozen D2O. The latter exhibits a narrower line and a single T1 and is attributed to the liquid surface water layer in rapid exchange with the nearby supercooled water, the quantity of which diminishes with the lowering of the temperature depending on the gel porosity. It is possible to measure the supercooled water quantity and to correct the T1 measured values to extract the T1 surface. The value extrapolated at room temperature allows the complete clay surface area measurement. The example of a montmorillonite is given and a comparison with laponite is made. PMID:9803898

Letellier, M

1998-01-01

418

Treatment of self-reported depression among Hispanics and African Americans.  

PubMed

This study applied the Behavioral Model for Vulnerable Populations framework to examine the correlates of depression and the receipt of medical treatment among low-income Hispanics and African Americans residing in public housing. We compared three groups: those who reported (1) self-diagnosed but without physician-diagnosed depression, (2) depression diagnosed by a physician but who did not receive pharmaceutical treatment, and (3) depression diagnosed by a physician and antidepressant pharmacotherapy consumed by patient. Random samples of 287 adults from three public housing communities were surveyed. Over 48% of this sample reported that they were suffering from depression. One out of three people who reported being depressed also said that a physician had never diagnosed his or her condition. Only 40% of those who said that a physician had diagnosed depression also reported taking antidepressant medication. Untreated depression among underserved racial and ethnic minorities is alarming and points to an urgent need for intervention. PMID:15937396

Bazargan, Mohsen; Bazargan-Hejazi, Shahrzad; Baker, Richard S

2005-05-01

419

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

SciTech Connect

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.

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

1993-04-01

420

Sexual minority status, peer harassment, and adolescent depression.  

PubMed

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

Martin-Storey, Alexa; Crosnoe, Robert

2012-08-01

421

Sexual Minority Status, Peer Harassment, and Adolescent Depression  

PubMed Central

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.

Martin-Storey, Alexa; Crosnoe, Robert

2012-01-01

422

Long-term stability of sterically stabilized liposomes by freezing and freeze-drying: Effects of cryoprotectants on structure  

Microsoft Academic Search

Liposomes are widely investigated for their use as drug delivery systems, where they have to meet strict stability criteria. Hence, it is of common interest to establish appropriate storage conditions to improve the shelf life of liposomes. In general, long-term stability can be achieved by freezing as well as freeze-drying, and different carbohydrates or polyalcohols, such as mannitol or glycerol

Brigitte Stark; Georg Pabst; Ruth Prassl

2010-01-01

423

Depression Care for Patients at Home (Depression CAREPATH): Home Care Depression Care Management Protocol  

PubMed Central

High levels of depressive symptoms are common and contribute to poorer clinical outcomes even in geriatric patients who are already taking antidepressant medication. The Depression CARE for PATients at Home (Depression CAREPATH) intervention was designed to meet the needs of medical and surgical patients who suffer from depression. The intervention’s clinical protocols are designed to guide clinicians in managing depression as part of routine home care.

Bruce, Martha L.; Raue, Patrick J.; Sheeran, Thomas; Reilly, Catherine; Pomerantz, Judith C.; Meyers, Barnett S.; Weinberger, Mark I.; Zukowski, Diane

2011-01-01

424

Depression Care for Patients at Home (Depression CAREPATH): home care depression care management protocol, part 2.  

PubMed

High levels of depressive symptoms are common and contribute to poorer clinical outcomes even in geriatric patients who are already taking antidepressant medication. The Depression CARE for PATients at Home (Depression CAREPATH) intervention was designed to meet the needs of medical and surgical patients who suffer from depression. The intervention's clinical protocols are designed to guide clinicians in managing depression as part of routine home care. PMID:21881429

Bruce, Martha L; Raue, Patrick J; Sheeran, Thomas; Reilly, Catherine; Pomerantz, Judith C; Meyers, Barnett S; Weinberger, Mark I; Zukowski, Diane

2011-09-01

425

A water activity based model of heterogeneous ice nucleation kinetics for freezing of water and aqueous solution droplets.  

PubMed

Immersion freezing of water and aqueous solutions by particles acting as ice nuclei (IN) is a common process of heterogeneous ice nucleation which occurs in many environments, especially in the atmosphere where it results in the glaciation of clouds. Here we experimentally show, using a variety of IN types suspended in various aqueous solutions, that immersion freezing temperatures and kinetics can be described solely by temperature, T, and solution water activity, a(w), which is the ratio of the vapour pressure of the solution and the saturation water vapour pressure under the same conditions and, in equilibrium, equivalent to relative humidity (RH). This allows the freezing point and corresponding heterogeneous ice nucleation rate coefficient, J(het), to be uniquely expressed by T and a(w), a result we term the a(w) based immersion freezing model (ABIFM). This method is independent of the nature of the solute and accounts for several varying parameters, including cooling rate and IN surface area, while providing a holistic description of immersion freezing and allowing prediction of freezing temperatures, J(het), frozen fractions, ice particle production rates and numbers. Our findings are based on experimental freezing data collected for various IN surface areas, A, and cooling rates, r, of droplets variously containing marine biogenic material, two soil humic acids, four mineral dusts, and one organic monolayer acting as IN. For all investigated IN types we demonstrate that droplet freezing temperatures increase as A increases. Similarly, droplet freezing temperatures increase as the cooling rate decreases. The log10(J(het)) values for the various IN types derived exclusively by Tand a(w), provide a complete description of the heterogeneous ice nucleation kinetics. Thus, the ABIFM can be applied over the entire range of T, RH, total particulate surface area, and cloud activation timescales typical of atmospheric conditions. Lastly, we demonstrate that ABIFM can be used to derive frozen fractions of droplets and ice particle production for atmospheric models of cirrus and mixed phase cloud conditions. PMID:24601020

Knopf, Daniel A; Alpert, Peter A

2013-01-01

426

Studies on Freezing RAM Semen in Absence of Glycerol.  

NASA Astrophysics Data System (ADS)

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.

Abdelnaby, Abdelhady Abdelhakeam

1988-12-01

427

Lifestyle medicine for depression  

PubMed Central

The prevalence of depression appears to have increased over the past three decades. While this may be an artefact of diagnostic practices, it is likely that there are factors about modernity that are contributing to this rise. There is now compelling evidence that a range of lifestyle factors are involved in the pathogenesis of depression. Many of these factors can potentially be modified, yet they receive little consideration in the contemporary treatment of depression, where medication and psychological intervention remain the first line treatments. “Lifestyle Medicine” provides a nexus between public health promotion and clinical treatments, involving the application of environmental, behavioural, and psychological principles to enhance physical and mental wellbeing. This may also provide opportunities for general health promotion and potential prevention of depression. In this paper we provide a narrative discussion of the major components of Lifestyle Medicine, consisting of the evidence-based adoption of physical activity or exercise, dietary modification, adequate relaxation/sleep and social interaction, use of mindfulness-based meditation techniques, and the reduction of recreational substances such as nicotine, drugs, and alcohol. We also discuss other potential lifestyle factors that have a more nascent evidence base, such as environmental issues (e.g. urbanisation, and exposure to air, water, noise, and chemical pollution), and the increasing human interface with technology. Clinical considerations are also outlined. While data supports that some of these individual elements are modifiers of overall mental health, and in many cases depression, rigorous research needs to address the long-term application of Lifestyle Medicine for depression prevention and management. Critically, studies exploring lifestyle modification involving multiple lifestyle elements are needed. While the judicious use of medication and psychological techniques are still advocated, due to the complexity of human illness/wellbeing, the emerging evidence encourages a more integrative approach for depression, and an acknowledgment that lifestyle modification should be a routine part of treatment and preventative efforts.

2014-01-01

428

Lifestyle medicine for depression.  

PubMed

The prevalence of depression appears to have increased over the past three decades. While this may be an artefact of diagnostic practices, it is likely that there are factors about modernity that are contributing to this rise. There is now compelling evidence that a range of lifestyle factors are involved in the pathogenesis of depression. Many of these factors can potentially be modified, yet they receive little consideration in the contemporary treatment of depression, where medication and psychological intervention remain the first line treatments. "Lifestyle Medicine" provides a nexus between public health promotion and clinical treatments, involving the application of environmental, behavioural, and psychological principles to enhance physical and mental wellbeing. This may also provide opportunities for general health promotion and potential prevention of depression. In this paper we provide a narrative discussion of the major components of Lifestyle Medicine, consisting of the evidence-based adoption of physical activity or exercise, dietary modification, adequate relaxation/sleep and social interaction, use of mindfulness-based meditation techniques, and the reduction of recreational substances such as nicotine, drugs, and alcohol. We also discuss other potential lifestyle factors that have a more nascent evidence base, such as environmental issues (e.g. urbanisation, and exposure to air, water, noise, and chemical pollution), and the increasing human interface with technology. Clinical considerations are also outlined. While data supports that some of these individual elements are modifiers of overall mental health, and in many cases depression, rigorous research needs to address the long-term application of Lifestyle Medicine for depression prevention and management. Critically, studies exploring lifestyle modification involving multiple lifestyle elements are needed. While the judicious use of medication and psychological techniques are still advocated, due to the complexity of human illness/wellbeing, the emerging evidence encourages a more integrative approach for depression, and an acknowledgment that lifestyle modification should be a routine part of treatment and preventative efforts. PMID:24721040

Sarris, Jerome; O'Neil, Adrienne; Coulson, Carolyn E; Schweitzer, Isaac; Berk, Michael

2014-01-01

429

The effects of freeze drying and freeze drying additives on the prothrombin time and the international sensitivity index.  

PubMed Central

AIM: To determine whether freezing, freeze drying protective additives, or freeze drying of plasma samples from patients on coumarin treatment and from normal individuals affects prothrombin times or the international sensitivity index (ISI) calibration. METHODS: The effect of the addition of the protective additives singly and combined on the prothrombin time of coumarin samples and normal samples before and after freeze drying was observed using high and low ISI reference thromboplastins. ISI values were also determined. RESULTS: Freezing caused a prolongation of prothrombin time in the normal plasma samples with both reagents, which was significant with the low ISI human. Prolongation (non-significant) of the prothrombin time in coumarin plasma samples occurred with the human reagent only. Significant prolongation of normal prothrombin time by some of the protective additives before and after freeze drying was observed with both thromboplastins but to a greater extent with the human. Significant prolongation of prothrombin time in coumarin plasma samples was observed, but again was more marked with human thromboplastin. An approximate ISI was determined on the 20 coumarin samples. The only marked ISI change was with the WHO human thromboplastin after freeze drying of plasma, where a decrease from 0.95 to 0.90 was observed, corresponding to a marked prothrombin ratio increase. CONCLUSIONS: Freeze drying additives and the freeze drying procedure prolong normal and coumarin prothrombin times, with low ISI thromboplastin. Less marked prolongations occurred with a high ISI rabbit reagent, coumarin samples showing more significant prolongations. Marked ISI change in freeze dried plasma was only recorded with the low ISI ECAA human reagent. Frozen normal plasma samples cannot be used with confidence for ISI calibrations.

Poller, L; Keown, M; Shepherd, S A; Shiach, C R; Tabeart, S

1999-01-01

430

Communication: A simple method for simulation of freezing transitions.  

PubMed

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

Orkoulas, G; Nayhouse, Michael

2011-05-01

431

Agomelatine, melatonin and depressive disorder.  

PubMed

Alteration of nocturnal melatonin production, along with circadian rhythm disturbance, has been demonstrated in several psychiatric disorders. It has been postulated that such disturbances might be causal reflecting a more fundamental abnormality of the function of the suprachiasmatic nucleus (SCN). The SCN contains the body's master 'clock' while the pineal-SCN nexus is intricate to the nighttime production of melatonin. The more compelling case for causality is made for major depressive disorder (MDD). Lending weight to this proposition is the introduction of agomelatine as an antidepressant agent. Through its actions on melatonin receptors agomelatine can resynchronise circadian rhythms. The circadian hypothesis would posit that normalisation of disturbance would be sufficient of itself to alleviate the symptoms of MDD. Thus, strategies designed to bring about resynchronisation of circadian rhythms should be therapeutically effective in depression. Critical examination of the efficacy of such interventions in MDD suggests that the circadian alteration may be necessary but is not sufficient for an antidepressant effect. Exogenous melatonin administration and bright light therapy have mixed results in limited controlled clinical evaluations. Furthermore, agomelatine has other actions which pre-clinical studies suggest are as important to its therapeutic effects as are its actions on melatonin receptors ipso facto its resynchronising properties. Whether circadian effects are antidepressant remains a moot point and awaits the clinical evaluation of highly selective resynchronising agents. PMID:23484857

Norman, Trevor R

2013-04-01

432

Impact of defense style on brief psychotherapy of postpartum depression.  

PubMed

In this study, we evaluated the impact of defense style (DS) on outcome and its relation to the therapeutic alliance. Women with postpartum depression were allocated to a brief psychotherapeutic intervention. To evaluate DS and the therapeutic alliance, the Defense Style Questionnaire and the Working Alliance Inventory were employed. The main outcome was the Edinburgh Postnatal Depression Scale score at end point; anxiety and retention in treatment were also evaluated. Fifty-nine patients were included; 46 completed the therapy and 65.4% responded (Edinburgh Postnatal Depression Scale score <10). Intense use of immature defenses was related to persistence of depression and anxiety symptoms at end point, even when controlled for potential confounders. Results tended to confirm a hierarchy of DSs independently of the alliance. Clinicians should be aware of possible differential responses to brief psychotherapies related to DS. PMID:18043530

Magalhães, Pedro Vieira da Silva; Pinheiro, Ricardo Tavares; Faria, Augusto Duarte; Osório, Camila Moreira; da Silva, Ricardo Azevedo; Botella, Luis

2007-10-01

433

Trajectories of Resilience, Depression, and Anxiety Following Spinal Cord Injury  

Microsoft Academic Search

Purpose\\/Objective: To investigate longitudinal trajectories of depression and anxiety symptoms following spinal cord injury (SCI) as well as the predictors of those trajectories. Research Method\\/Design: A longitudinal study of 233 participants assessed at 4 time points: within 6 weeks, 3 months, 1 year, and 2 years from the point of injury. Data were analyzed using latent growth mixture modeling to

George A. Bonanno; Paul Kennedy; Isaac R. Galatzer-Levy; Peter Lude; Mangus L. Elfström

2012-01-01

434

Metabolic changes in Avena sativa crowns recovering from freezing.  

PubMed

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

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

2014-01-01

435

Freeze-thaw durability of air-entrained concrete.  

PubMed

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

Shang, Huai-Shuai; Yi, Ting-Hua

2013-01-01

436

Metabolic Changes in Avena sativa Crowns Recovering from Freezing  

PubMed Central

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.

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

2014-01-01

437

Assigning thermodynamic temperatures to high-temperature fixed-points  

NASA Astrophysics Data System (ADS)

Workpackage five of the High Temperature Fixed-Point research programme will determine the thermodynamic temperature for the equilibrium melting transition of the pure eutectic systems of Re-C, Pt-C and Co-C and, in addition, the freezing point of Cu. Measurements of four different cells of each type will be made by nine participating laboratories. This paper describes how the melt sensitivity to the rate of the previous freeze, furnace effects and cell impurities will be accounted for and how the results will be combined allowing for all existing correlations.

Woolliams, E. R.; Bloembergen, P.; Machin, G.

2013-09-01

438

Magnesium in depression.  

PubMed

Magnesium is one of the most essential mineral in the human body, connected with brain biochemistry and the fluidity of neuronal membrane. A variety of neuromuscular and psychiatric symptoms, including different types of depression, was observed in magnesium deficiency. Plasma/serum magnesium levels do not seem to be the appropriate indicators of depressive disorders, since ambiguous outcomes, depending on the study, were obtained. The emergence of a new approach to magnesium compounds in medical practice has been seen. Apart from being administered as components of dietary supplements, they are also perceived as the effective agents in treatment of migraine, alcoholism, asthma, heart diseases, arrhythmias, renal calcium stones, premenstrual tension syndrome etc. Magnesium preparations have an essential place in homeopathy as a remedy for a range of mental health problems. Mechanisms of antidepressant action of magnesium are not fully understood yet. Most probably, magnesium influences several systems associated with development of depression. The first information on the beneficial effect of magnesium sulfate given hypodermically to patients with agitated depression was published almost 100 years ago. Numerous pre-clinical and clinical studies confirmed the initial observations as well as demonstrated the beneficial safety profile of magnesium supplementation. Thus, magnesium preparations seem to be a valuable addition to the pharmacological armamentarium for management of depression. PMID:23950577

Serefko, Anna; Szopa, Aleksandra; Wla?, Piotr; Nowak, Gabriel; Radziwo?-Zaleska, Maria; Skalski, Micha?; Poleszak, Ewa

2013-01-01

439

Hypothyroidism and Depression  

PubMed Central

Background: A relationship between hypothyroidism and depression has been assumed for many years; however, the true nature of this association has been difficult to define with many conflicting studies. In recent years, our knowledge in this area has increased significantly with large cohort studies and genetically driven studies being published. Objectives: We reviewed the literature on thyroid function and depression to determine if this relationship has been clarified. Methods: We performed a search on the Pubmed database using the terms ‘thyroid? ’ and ‘mental health? ’, ‘depression? ’ and ‘well-being? ’. Results: Large epidemiological studies generally suggest no association between thyroid function and depression in subjects without thyroid disease. Subjects on thyroxine have poorer psychological well-being than subjects with no thyroid disease even if biochemically euthyroid, they also show an association between thyroid function and well-being. Whilst there is some early evidence that genetic factors can influence well-being on thyroxine and response to combination therapy, there is also evidence to suggest that much morbidity on thyroxine may be due to initial misdiagnosis and mis-attribution of symptoms. Conclusion: Despite the large number of studies, the relationship between thyroid function and depression remains poorly defined. Clarification of the proportion of subjects on thyroxine incorrectly may assist the large (perhaps genetically driven) studies needed to move forward in this area, as it is expected that they cloud the results.

Dayan, Colin M.; Panicker, Vijay

2013-01-01

440

[Metabolic syndrome and depression].  

PubMed

The metabolic syndrome is defined as a constellation of metabolic abnormalities, including glucose intolerance, obesity, dyslipidaemia, and hypertension. It is associated with an elevated risk for cardiovascular disease and type 2 diabetes. Over the past 20 years, a worldwide increase of the metabolic syndrome has taken place. In the USA, 21% to 39% of the general population suffer from metabolic syndrome; in Europe prevalence rates are lower. At the same time, depressive disorders, which are associated with a 1.5 to 2.5 fold risk for cardiovascular events, are increasing. The combination of metabolic syndrome and depression multiplies the risk for severe complications: Due to behavioural, physiological, genetic, and treatment-induced factors, depression stimulates the development of a metabolic syndrome. In reverse, the metabolic syndrome favours development and maintenance of the metabolic syndrome. Consequently, in patients suffering from metabolic syndrome and depression, both disorders must be treated simultaneously. The treatment plan includes weight reduction, physical activity, psychoeducation, family interventions, the patient's subjective explanatory and treatment models, cognitive techniques, and problem solving techniques. Weight, blood pressure, fastening glucose, haemoglobin A1c, and lipids must be controlled in order to monitor treatment progress. Additional drug treatment can be appropriate for hypertension, dyslipidaemia, hyperglycaemia, and depression. Under these conditions, sustained improvements of individual well-being, psychosocial risk-factors, functional limitations, glycemic control, hypertension, and obesity are possible. PMID:16941396

Löwe, B; Hochlehnert, A; Nikendei, C

2006-08-01

441

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

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

Osvaldo P. Almeida; Shirley A. Almeida

1999-01-01

442

Depression and Coronary Heart Disease  

PubMed Central

There are exciting findings in the field of depression and coronary heart disease. Whether diagnosed or simply self-reported, depression continues to mark very high risk for a recurrent acute coronary syndrome or for death in patients with coronary heart disease. Many intriguing mechanisms have been posited to be implicated in the association between depression and heart disease, and randomized controlled trials of depression treatment are beginning to delineate the types of depression management strategies that may benefit the many coronary heart disease patients with depression.

Davidson, Karina W.

2012-01-01

443

Depression and coronary heart disease.  

PubMed

There are exciting findings in the field of depression and coronary heart disease. Whether diagnosed or simply self-reported, depression continues to mark very high risk for a recurrent acute coronary syndrome or for death in patients with coronary heart disease. Many intriguing mechanisms have been posited to be implicated in the association between depression and heart disease, and randomized controlled trials of depression treatment are beginning to delineate the types of depression management strategies that may benefit the many coronary heart disease patients with depression. PMID:23227360

Davidson, Karina W

2012-01-01

444

Spatiotemporal measurement of freezing-induced deformation of engineered tissues.  

PubMed

In order to cryopreserve functional engineered tissues (ETs), the microstructure of the extracellular matrix (ECM) should be maintained, as well as the cellular viability since the functionality is closely related to the ECM microstructure. Since the post-thaw ECM microstructure is determined by the deformation of ETs during cryopreservation, freezing-induced deformation of ETs was measured with a newly developed quantum dot (QD)-mediated cell image deformetry system using dermal equivalents as a model tissue. The dermal equivalents were constructed by seeding QD-labeled fibroblasts in type I collagen matrices. After 24 h incubation, the ETs were directionally frozen by exposing them to a spatial temperature gradient (from 4 degrees C to -20 degrees C over a distance of 6 mm). While being frozen, the ETs were consecutively imaged, and consecutive pairs of these images were two-dimensionally cross-correlated to determine the local deformation during freezing. The results showed that freezing induced the deformation of ET, and its magnitude varied with both time and location. The maximum local dilatation was 0.006 s(-1) and was always observed at the phase change interface. Due to this local expansion, the unfrozen region in front of the freezing interface experienced compression. This expansion-compression pattern was observed throughout the freezing process. In the unfrozen region, the deformation rate gradually decreased away from the freezing interface. After freezing/thawing, the ET experienced an approximately 28% decrease in thickness and 8% loss in weight. These results indicate that freezing-induced deformation caused the transport of interstitial fluid, and the interstitial fluid was extruded. In summary, the results suggest that complex cell-fluid-matrix interactions occur within ETs during freezing, and these interactions determine the post-thaw ECM microstructure and eventual post-thaw tissue functionality. PMID:20459191

Teo, Ka Yaw; Dutton, J Craig; Han, Bumsoo

2010-03-01

445

Size Control in Production and Freeze-Drying of Poly-?-Caprolactone Nanoparticles.  

PubMed

This work is focused on the control of poly-?-caprolactone nanoparticle characteristics, notably size and size distribution, in both the production and preservation (by using freeze-drying) stages. Nanoparticles were obtained by employing the solvent displacement method in a confined impinging jets mixer. The effect of several operating conditions, namely, initial polymer concentration and solvent-to-antisolvent flow rate ratio, and the influence of postprocessing conditions, such as final dilution and solvent evaporation, on nanoparticle characteristics was investigated. Further addition of antisolvent (water) after preparation was demonstrated to be effective in obtaining stable nanoparticles, that is, avoiding aggregation that would result in larger particles. On the contrary, solvent (acetone) evaporation was shown to have a small effect on the final nanoparticle characteristics. Eventually, freeze-drying of the solutions containing nanoparticles, after solvent evaporation, was also investigated. To ensure maximum nanoparticles stability, lyoprotectants (e.g., sucrose and mannitol) and steric stabilizers (e.g., Cremophor EL and Poloxamer 388) had to be added to the suspensions. The efficacy of the selected lyoprotectants, in the presence (or absence) of steric stabilizers, and in various concentrations, to avoid particle aggregation during the freeze-drying process was investigated, thus pointing to the optimal formulation. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci. PMID:24737658

Zelenková, Tereza; Fissore, Davide; Marchisio, Daniele L; Barresi, Antonello A

2014-06-01

446

Freezing fingers syndrome, primary and secondary Raynaud's phenomenon: characteristic features with hand thermography.  

PubMed

The aim of the present study was to establish a thermographic model of healthy subjects' hands and compare it with a model of the hands of patients with freezing fingers syndrome, a group usually regarded as a healthy population. A further aim was to establish the thermographic parameters that distinguish primary Raynaud's phenomenon (RP) from secondary RP. The study was conducted on a group of 74 subjects, divided into 3 groups: patients with freezing hands symptoms (G1), those with primary RP (G2), and those with limited scleroderma (G3). In addition, 69 healthy volunteers served as a control group (G4). The most distinctive features of healthy subjects' hands are the thermal symmetry between left to right measurements (?T<0.5°C) and between mean temperatures of the metacarpus and digits (?T<0.5°C (1°C maximum)). A negative correlation was found between mean hands temperature and age of subjects in G4 (p<0.0001). All the temperatures observed in G4 subjects were significantly higher than among patients in G1, G2 and G3 (p<0.001). No significant differences were found between mean temperatures in G2 and G3. RP should be suspected when differences between mean temperatures of the metacarpus and digits are ?to 3ºC. Moreover, we suggest that a cut-off point >1ºC is established for subjects with "freezing" symptoms. PMID:23314682

Chlebicka, Iwona; Matusiak, ?ukasz; Maj, Joanna; Baran, Eugeniusz; Szepietowski, Jacek C

2013-07-01

447

Interpretation of freezing nucleation experiments: singular and stochastic; sites and surfaces  

NASA Astrophysics Data System (ADS)

Publications of recent years dealing with laboratory experiments of immersion freezing reveal uncertainties about the fundamentals of heterogeneous freezing nucleation. While it appears well accepted that there are two major factors that determine the process, namely fluctuations in the size and configuration of incipient embryos of the solid phase and the role of the substrate to aid embryo formation, views have been evolving about the relative importance of these two elements. The importance of specific surface sites is being established in a growing number of experiments and a number of approaches have been proposed to incorporate these results into model descriptions. Many of these models share a common conceptual basis yet diverge in the way random and deterministic factors are combined. The divergence can be traced to uncertainty about the permanence of nucleating sites, to the lack of detailed knowledge about what surface features constitute nucleating sites, and to the consequent need to rely on empirical or parametric formulas to define the population of sites of different effectiveness. The goal of this paper is to demonstrate that recent experiments and models, consistent with earlier work, point to the existence and primary role of permanent nucleating sites and to the continued need for empirically based formulations of heterogeneous freezing. The paper focuses on three identifiably separate but interrelated issues: (i) the combination of singular and stochastic factors, (ii) the role of specific surface sites, and (iii) the modeling of heterogeneous ice nucleation.

Vali, G.

2014-01-01

448