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1

Study of freezing-point depression of selected food extracts  

SciTech Connect

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

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

1996-12-31

2

Structurally Caused Freezing Point Depression of Biological Tissues  

PubMed Central

When investigating the freezing behaviour (by thermal analysis) of the glycerol-extracted adductor muscle of Mytilus edulis it was observed that the temperature of ice formation in the muscular tissue was up to 1.5°C lower than the freezing point of the embedding liquid, a 0.25 N KCl solution with pH = 4.9 with which the tissue had been equilibrated prior to the freezing experiment. A smaller freezing point depression was observed if the pH values of the embedding 0.25 N KCl solution were above or below pH = 4.9. Reasoning from results obtained previously in analogous experiments with artificial gels, the anomalous freezing depression is explained by the impossibility of growing at the normal freezing temperature regular macroscopic crystals inside the gel, due to the presence of the gel network. The freezing temperature is here determined by the size of the microprisms penetrating the meshes of the network at the lowered freezing temperature. This process leads finally to an ice block of more or less regular structure in which the filaments are embedded. Prerequisite for this hindrance of ideal ice growth is a sufficient tensile strength of the filamental network. The existence of structurally caused freezing point depression in biological tissue is likely to invalidate many conclusions reported in the literature, in which hypertonicity was deduced from cryoscopic data. PMID:13971682

Bloch, Rene; Walters, D. H.; Kuhn, Werner

1963-01-01

3

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

4

Measurement of Freezing Point Depression of Selected Food Solutions  

NASA Astrophysics Data System (ADS)

Freezing point depression of selected food solutions were measured at various concentrations in order to reveal the characteristics of solid-liquid phase equilibrium. The measurement were carried out on a hand made apparatus that was calibrated before the measurement by some of selected reagents (acid and sugar) with known thermal properties. The results revealed that the freezing point depression of selected food solutions deviated from the behavior of the ideal solution with increasing solute concentration, so the water activity for non-ideal solution were introduced to the freezing point depression equation. Further, assuming that the heat of fusion was a equation of temperature, thus the following new equation was led, ln {(1-Xs)/(l-Xs+?·Xs + ?·Xs2)} = A(1/To - 1/Tf) - Bln(To/Tf) The goodness of fit of the equation showed the best results. Futhermore, by using the parameters a formula of freezing ratio and the relative water activities, which showed deviation from the ideal solution, were derived.

Murata, Satoshi; Tanaka, Fumihiko; Matsuoka, Takahisa

5

THE FREEZING POINT DEPRESSION OF MAMMALIAN TISSUES AFTER SUDDEN HEATING IN BOILING DISTILLED WATER  

Microsoft Academic Search

The calculated freezing point depression of freshly excised boiled mammalian tissue is approximately the same as that of plasma. The boiling procedure was chosen to eliminate the influence of metabolism on the level of the freezing point depression. Problems created by the boiling, such as equilibrium between tissue and diluent, change in activity coefficient by dilution, and loss of CO~

J. W. Th. Appelboom; WILLIAM A. BRODSK; WILLIAM S. TUTTLE; ISRAEL DIAMOND

1958-01-01

6

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

7

Preliminary report on fluid inclusions from halites in the Castile and lower Salado formations of the Delaware Basin, southeastern New Mexico. [Freezing-point depression  

SciTech Connect

A suite of samples composed primarily of halite from the upper Castile and lower Salado Formations of the Permian Basin was selected from Waste Isolation Pilot Plant (WIPP) core for a reconnaissance study of fluid inclusions. Volume percent of these trapped fluids averaged 0.7% to 1%. Freezing-point depressions varied widely and appeared to be unrelated to fluid-inclusion type, to sedimentary facies, or to stratigraphic depth. However, because very low freezing points were usually associated with anhydrite, a relation may exist between freezing-point data and lithology. Dissolved sulfate values were constant through the Castile, then decreased markedly with lesser depth in the lower Salado. This trend correlates very well with observed mineralogy and is consistent with an interpretation of the occurrence of secondary polyhalite as a result of gypsum or anhydrite alteration with simultaneous consumption of dissolved sulfate from the coexisting fluids. Together with the abundance and distribution of fluid inclusions in primary or ''hopper'' crystal structures, this evidence suggests that inclusions seen in these halites did not migrate any significant geographical distance since their formation. 28 refs., 17 figs., 2 tabs.

Stein, C.L.

1985-09-01

8

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.)

9

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...

10

Improve online freeze and cloud point control  

SciTech Connect

To improve financial performance, petroleum refiners want tighter control on individual processing units. Consequently, modern refineries are moving product-quality analytical functions closer to process. Historically, processing units sent product samples to the laboratory and made adjustments based on analytical results. In some cases, the lag time between sample procurement an data return could be several hours. During this time, the unit could be producing off-spec product or operating in a nonoptimized mode while waiting on lab results. Under these conditions, the cost to the refinery could mean the difference between a profit or loss. Many quality requirements are associated with the refined products. Some are regulatory mandates, others are market or seasonally driven and some are driven by yield and process optimization objectives. For example, freeze and cloud point are process control parameters that can increase yields and improve financial performance. Opting to use online analyzers to monitor/control freeze and cloud point specifications has potential economical advantages. The paper discusses freeze and cloud point data, common problems with analyzers, and two case histories of monitoring petroleum refinery streams.

Davidson, F.; Tsang, C. [Phase Technology, Richmond, British Columbia (Canada)

1997-01-01

11

When the Melting and Freezing Points are not the Same  

Microsoft Academic Search

Almost every solid has a melting point, and almost every liquid has a freezing point. These two points are one and the same, just viewed from different perspectives: ice melts at zero degrees Celsius--the highest temperature at which it can be a stable solid--whereas water freezes at zero degrees C--the lowest temperature at which it can be a stable liquid.

R. Stephen Berry

1990-01-01

12

Open Zinc Freezing-Point Cell Assembly and Evaluation  

NASA Astrophysics Data System (ADS)

An open metal freezing-point cell design has been developed in the Laboratory of Metrology and Quality. According to our design, a zinc cell was successfully assembled. The paper presents the needed parts for the cell, the cleaning process, and sealing of the cell. The assembled cell was then evaluated by comparison with two commercial closed zinc cells of different manufacturers. The freezing plateaus of the cells were measured, and a direct cell comparison was made. It was shown that the assembled open cell performed better than the used closed cell and was close to the brand new closed cell. The nominal purity of the zinc used for the open cell was 7 N, but the freezing plateau measurement suggests a higher impurity concentration. It was assumed that the zinc was contaminated to some extent during the process of cutting as its original shape was an irregular cylinder. The uncertainty due to impurities for the assembled cell is estimated to be 0.3 mK. Furthermore, the immersion profile and the pressure coefficient were measured. Both results are close to their theoretical values.

Žužek, V.; Batagelj, V.; Drnovšek, J.; Bojkovski, J.

2014-07-01

13

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

14

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

15

Fuel freeze-point investigations. Final report, September 1982-March 1984  

SciTech Connect

The objective of this program was to conduct a detailed assessment of the low-temperature environment to which USAF aircraft are exposed for the purpose of defining a maximum acceptable fuel freeze-point and also to define any operational changes required with the use of a high freeze-point fuel. A previous study of B-52, C-141, and KC-135 operational missions indicated that the -58 C freeze point specification was too conservative. Based on recommendations resulting from the previous program, several improvements in the method of analysis were made, such as: expansion of the atmospheric temperature data base, the addition of ground temperature analysis, the addition of fuel-freezing analysis to the one-dimensional fuel-temperature computer program, and the examination of heat transfer in external fuel tanks, such as pylon or tip tanks. The B-52, C-141, and KC-135 mission were analyzed again, along with the operational missions of two tactical airplanes, the A-10 and F-15; -50C was determined to be the maximum allowable freeze point for a general-purpose USAF aviation turbine fuel. Higher freeze points can be tolerated if the probability of operational interference is acceptably low or if operational changes can be made. Study of atmospheric temperatures encountered for the missions of the five-study aircraft indicates that a maximum freeze point of -48 C would not likely create any operational difficulties in Northern Europe.

Desmarais, L.A.; Tolle, F.F.

1984-07-01

16

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

17

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

NASA Astrophysics Data System (ADS)

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

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

2008-06-01

18

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

19

Ozonized vegetable oil as pour point depressant for neat biodiesel  

Microsoft Academic Search

The use of ozonized vegetable oils as pour point depressant for neat biodiesel was evaluated. Ozonized vegetable oils (1–1.5% by weight) were effective in reducing the pour point of biodiesel prepared from sunflower oil, soybean oil and rapeseed oil to ?24, ?12 and ?30°C, respectively. Cloud point however remained unaffected. In the case of palm oil biodiesel, significant reduction was

Nestor U. Soriano; Veronica P. Migo; Masatoshi Matsumura

2006-01-01

20

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

21

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

NASA Astrophysics Data System (ADS)

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

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

2003-09-01

22

A method for on-line determination of residual water content and sublimation end-point during freeze-drying  

Microsoft Academic Search

Freeze-drying is a discontinuous process mainly used in the food and pharmaceutical industry to preserve the initial properties of raw products after dehydration. To date, the freeze-drying process has been monitored according to time-dependent empirical rules. Several authors have attempted to develop measuring systems for the on-line determination of the dehydration rate (freeze-drying kinetics) and the sublimation end-point. Of the

N. Genin; F. Rene; G. Corrieu

1996-01-01

23

The frozen soul: sin and forgiveness in Miura Ayako's Freezing Point  

Microsoft Academic Search

Miura Ayako (1922–99) rose from obscurity to literary stardom on the basis of her first novel, Hy?ten, published serially in 1964–5, and became in the process not only one of Japan's best-selling novelists but also one of its leading Christian voices. Hy?ten (Freezing point), one of the best-known and most widely read novels of the past few decades, follows the

Philip Gabriel

2005-01-01

24

The Nonparametric Analysis of Point Process Data: The Freezing History of Lake Konstanz.  

NASA Astrophysics Data System (ADS)

Climate records sometimes have the form of point processes (i.e., observations of the times of occurrence of a specified type of event). A central problem in the analysis of point process data is the estimation of the rate function, defined as the expected number of events occurring in a time interval of unit length. This paper describes some simple nonparametric methods for estimating the rate function and for assessing its statistical significance. The methods are applied to the freezing history of Lake Konstanz.

Solow, Andrew R.

1991-01-01

25

Determination of end point of primary drying in freeze-drying process control.  

PubMed

Freeze-drying is a relatively expensive process requiring long processing time, and hence one of the key objectives during freeze-drying process development is to minimize the primary drying time, which is the longest of the three steps in freeze-drying. However, increasing the shelf temperature into secondary drying before all of the ice is removed from the product will likely cause collapse or eutectic melt. Thus, from product quality as well as process economics standpoint, it is very critical to detect the end of primary drying. Experiments were conducted with 5% mannitol and 5% sucrose as model systems. The apparent end point of primary drying was determined by comparative pressure measurement (i.e., Pirani vs. MKS Baratron), dew point, Lyotrack (gas plasma spectroscopy), water concentration from tunable diode laser absorption spectroscopy, condenser pressure, pressure rise test (manometric temperature measurement or variations of this method), and product thermocouples. Vials were pulled out from the drying chamber using a sample thief during late primary and early secondary drying to determine percent residual moisture either gravimetrically or by Karl Fischer, and the cake structure was determined visually for melt-back, collapse, and retention of cake structure at the apparent end point of primary drying (i.e., onset, midpoint, and offset). By far, the Pirani is the best choice of the methods tested for evaluation of the end point of primary drying. Also, it is a batch technique, which is cheap, steam sterilizable, and easy to install without requiring any modification to the existing dryer. PMID:20058107

Patel, Sajal M; Doen, Takayuki; Pikal, Michael J

2010-03-01

26

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

27

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

28

Absolute Spectral Radiometric Determination of the Thermodynamic Temperatures of the Melting\\/Freezing Points of Gold, Silver and Aluminium  

Microsoft Academic Search

Narrow band filter radiometers have been used to measure the spectral radiance of black bodies held at the melting\\/freezing points of aluminium, silver and gold with an accuracy of 0,04%. Descriptions are given of the optical components and the techniques used for their characterization. As the measurements are absolute, the thermodynamic temperatures of these points can be calculated directly from

N. P. Fox; J. E. Martin; D. H. Nettleton

1991-01-01

29

Freeze-dried plasma at the point of injury: from concept to doctrine.  

PubMed

While early plasma transfusion for the treatment of patients with ongoing major hemorrhage is widely accepted as part of the standard of care in the hospital setting, logistic constraints have limited its use in the out-of-hospital setting. Freeze-dried plasma (FDP), which can be stored at ambient temperatures, enables early treatment in the out-of-hospital setting. Point-of-injury plasma transfusion entails several significant advantages over currently used resuscitation fluids, including the avoidance of dilutional coagulopathy, by minimizing the need for crystalloid infusion, beneficial effects on endothelial function, physiological pH level, and better maintenance of intravascular volume compared with crystalloid-based solutions. The Israel Defense Forces Medical Corps policy is that plasma is the resuscitation fluid of choice for selected, severely wounded patients and has thus included FDP as part of its armamentarium for use at the point of injury by advanced life savers, across the entire military. We describe the clinical rationale behind the use of FDP at the point-of-injury, the drafting of the administration protocol now being used by Israel Defense Forces advanced life support providers, the process of procurement and distribution, and preliminary data describing the first casualties treated with FDP at the point of injury. It is our hope that others will be able to learn from our experience, thus improving trauma casualty care around the world. PMID:24089000

Glassberg, Elon; Nadler, Roy; Gendler, Sami; Abramovich, Amir; Spinella, Philip C; Gerhardt, Robert T; Holcomb, John B; Kreiss, Yitshak

2013-12-01

30

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. PMID:15306323

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

2004-01-01

31

When hot water freezes before cold  

E-print Network

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

J. I. Katz

2006-04-27

32

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

E-print Network

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

Allen, Leslie H.

33

Final report for the APMP.T-K4: Comparison of realizations of aluminium freezing-point temperatures  

NASA Astrophysics Data System (ADS)

The comparison APMP.T-K4 is the regional extension of the CCT-K4: an intercomparison of the realizations of the freezing-points of Al (660.323 °C) and Ag (961.78 °C). The comparison was organized in two loops and four sub-loops with high temperature standard platinum resistance thermometers (HTSPRTs) as transfer thermometers in the freezing-point comparisons. The comparison involved eight APMP NMIs (KRISS, NMIJ, SCL, NMC, CMS, NIMT, SIRIM, NPL), and KRISS and NMIJ acted as linking laboratories to the CCT-K4. The transfer HTSPRTs showed a strong drift during the transportation between the NMIs. In the case of the Ag freezing-point comparison, the comparison results were scattered much more than expected. In the APMP meeting held in 2009, the participants agreed that the Ag comparison results would be omitted in the report. It revealed that the measurement results at the Al freezing-point of participants were in agreement with the key comparison reference value of the CCT-K4 within 4 mK except for one laboratory. Details of the comparison results, the uncertainty evaluation and the drift of the HTSPRTs are described in this report. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Gam, K. S.; Joung, W.; Yamazawa, K.; Cheung, C. P.; Y Kho, H.; Wang, L.; Tsai, S. F.; Norranim, U.; Hafidzah, O.; Gupta, J. K.

2013-01-01

34

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

35

DFT and MM calculation: the performance mechanism of pour point depressants study  

Microsoft Academic Search

Adding pour point depressants (PPDs) to lower the cold filter plugging point (CFPP) of oils has been widely used as the most valuable way in the world. To develop the new type of PPDs according to the oils of different kinds, many researchers have tried to study the performance mechanism of PPDs with different methods. In this article, we have

Jinli Zhang; Chuanjie Wu; Wei Li; Yiping Wang; Hui Cao

2004-01-01

36

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

PubMed Central

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

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

2014-01-01

37

A NOTE ON THE FREEZING-POINTS OF THE URINES OF TWO FRESH-WATER FISHES: THE CATFISH (AMEIURUS NEBULOSUS@ AND THE SUCKER (CATOSTOMUS COMMERSONI1)  

Microsoft Academic Search

In his book, Osmotic Regulation in Aquatic Animals, Krogh (1939) comments on the scarcity of available data for the osmotic concentra tion of the urines of fresh-water fishes. Since such data are appar ently not available for two of our common local forms, the catfish (Ameiurus nebulosus) and the sucker (Catostomus commersonii), we have been interested to make freezing-point determinations

CHARLOTTE HAYWOOD; MARY JEANNE CLAPP

38

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

39

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

40

Molecular dynamics simulation guiding the improvement of EVA-type pour point depressant  

Microsoft Academic Search

Addition of pour point depressants (PPDs) has been proved to be an efficient way to inhibit wax deposition of diesel fuels. However, the complexity of the oil is far beyond current commercial PPD products. So far it mainly depends on syntheses of numerous candidate compounds followed by repeating experimental measurements in order to improve the efficiency of PPDs. In this

Chuanjie Wu; Jin-li Zhang; Wei Li; Nan Wu

2005-01-01

41

Evaluation of Effect of Polymeric Pour Point Depressant Additives on Indian Waxy Crude Oil  

Microsoft Academic Search

Wax deposition in oil production constitutes a critical and difficult-to-control problem in terms of productivity and production operation costs going from the reservoir to surface facilities. In the present work, four polymeric additives were prepared and used as pour point depressants (PPD) for Limbodara (Indian) crude oil via polymerization of different undecylenates with maleic anhydride with a further reaction with

S. Deshmukh; D. Bharambe

2009-01-01

42

Depression  

MedlinePLUS

... the patient is under anesthesia. Healthy Minds TV - Depression Suicide Prevention Lifeline Depression education campaign from the Partnership ... from The Joint Commission: Let's Talk Facts Brochures: Depression Teen Suicide ECT

43

Depression  

MedlinePLUS

... usually feel better with the right treatment. What Causes Depression? There is no one cause of depression. For ... changes in the brain can affect mood and cause depression. Sometimes, those under a lot of stress, like ...

44

Depression  

MedlinePLUS

... com mh010106 Last reviewed: 07/28/2013 2 Causes of Depression Combination of genetic, psychological, and environmental factors can cause depression. Major depression is often associated with changes in ...

45

Freezing in confined geometries  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

46

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

47

Depressants  

MedlinePLUS

... illicit market. Teens can obtain depressants from the family medicine cabinet, friends, family members, the Internet, doctors, and ... illicit market. Teens can obtain depressants from the family medicine cabinet, friends, family members, the Internet, doctors, and ...

48

Depression  

MedlinePLUS

... loss Feelings of worthlessness Thoughts of death or suicide Depression is a disorder of the brain. There are a variety of causes, including genetic, environmental, psychological, and biochemical factors. Depression ...

49

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

E-print Network

Size-dependent melting point depression of nanostructures: Nanocalorimetric measurements M. Zhang in terms of existing melting point depression models. Excellent agreement with the homogeneous melting depression--small particles have a lower melting point than bulk material.3�5 This results from the increas

Allen, Leslie H.

50

Depression  

MedlinePLUS

... long time following a loss may require treatment. Depression and Suicide Though it is widely believed that suicide more ... men age 85 and older have the highest suicide rate in the United States. Types of Depression There are several types of depression. The most ...

51

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

52

Influence of freezing temperatures on a cactus, Coryphantha vivipara  

Microsoft Academic Search

Coryphantha vivipara (Nutt.) Britton & Rose var. deserti (Engelm.) W.T. Marshall (Cactaceae) survived snow and tissue temperatures of-12°C in southern Nevada. However, the freezing point depression of the cell sap was only about 0.9°C. When the nocturnal air temperature in the laboratory was reduced from 10°C to-10°C for one night, the optimum temperature for CO2 uptake shifted from 10°C to

Park S. Nobel

1981-01-01

53

Study on performance mechanism of pour point depressants with differential scanning calorimeter and X-ray diffraction methods  

Microsoft Academic Search

Adding pour point depressants (PPD) to lower the Cold Filter Plugging Point (CFPP) of diesel fuels is an effective and economic way of improving the cold flow properties of the oils. EVAP is a new type of PPD and has an excellent effect in lowering the CFPP of most Chinese diesel fuels. To further the development of this PPD product,

Jinli Zhang; Chuanjie Wu; Wei Li; Yiping Wang; Zhenting Han

2003-01-01

54

Development of a complex type of pour point-viscosity depressant and infrared spectrum research  

SciTech Connect

EMS, a complex type of pour point-viscosity depressant for crudes, is composed of EVA, MVA [molecular structure shown for both in the paper] and Surfactant. After adding EMS into the crudes, a very nice result in reducing pour point and viscosity for Daqing, Jianghan and Jidong crudes was obtained. From the research result of infrared spectroscopy of the interactions between EMS or its components and wax or mixture of resin and asphaltene isolated from three crudes, it has been shown that the area ratio of the double absorption peaks of 719 cm{sup {minus}1} and 729 cm{sup {minus}1} or 1,368 cm{sup {minus}1} and 1,378 cm{sup {minus}1} changed remarkably after EMS or its components were added into wax. It can be inferred that the cocrystallization probably happened between the EMS or its components and the wax. The position of the 4,000--3,000 cm{sup {minus}1} infrared absorption peak of the mixture of resin and asphaltene moved to the lower wavenumber, and the ratio of the area of 1,373 cm{sup {minus}1} absorption peak (methyl) to the combination area of 748, 810 and 871 cm{sup {minus}1} absorption peak (aromatics) increased remarkably. It can be inferred that the pour point-viscosity depressant molecules destroyed the original hydrogen bonds and overlapping of the aromatic ring planes among resin and asphaltene molecules to form a new cubic molecular structure and new hydrogen bonds with the results the viscosity of crude oil will be reduced.

Zhang Fusheng; Wang Biao [Scientific Research Inst. of Petroleum Exploration and Development, Beijing (China)

1995-11-01

55

Depression.  

PubMed

This is an invited article on how my career as an epidemiologist studying depression unfolded. The role of the Civil Rights movement in opening the PhD doors to women at Yale began my career. The unfolding of depression studies are described. These studies included a clinical trial of medication and what later was known as interpersonal psychotherapy (IPT), the first community survey of psychiatric disorder, family genetic and brain imaging studies or depression and anxiety disorders. I hope the new generation will have the wonderful opportunities I have had. PMID:19344866

Weissman, Myrna

2009-04-01

56

Depression  

MedlinePLUS

... care provider will find out how severe your depression is (mild, moderate, or severe) and look for the cause by doing a: Health history Mental health interview Physical examination If there is a risk of suicide, you may need to stay in the hospital ...

57

Freeze-fracture cytochemistry: replicas of critical point-dried cells and tissues after fracture-label.  

PubMed

Applications of the new fracture-labeling techniques for the observation of cytochemical labels on platinum-carbon replicas are described. Frozen cells, embedded in a cross-linked protein matrix, and frozen tissues are fractured with a scalpel under liquid nitrogen, thawed, labeled, dehydrated by the critical point drying method, and replicated. This method allows direct, high-resolution, two-dimensional chemical and immunological characterization of the cellular membranes in situ, as well as detection of sites within cross-fractured cytoplasm and extracellular matrix. PMID:7244630

da Silva, P P; Kachar, B; Torrisi, M R; Brown, C; Parkison, C

1981-07-10

58

Satellite freeze forecast system  

NASA Technical Reports Server (NTRS)

Provisions for back-up operations for the satellite freeze forecast system are discussed including software and hardware maintenance and DS/1000-1V linkage; troubleshooting; and digitized radar usage. The documentation developed; dissemination of data products via television and the IFAS computer network; data base management; predictive models; the installation of and progress towards the operational status of key stations; and digital data acquisition are also considered. The d addition of dew point temperature into the P-model is outlined.

Martsolf, J. D. (principal investigator)

1983-01-01

59

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

60

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

61

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

62

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. PMID:23862109

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

2013-01-01

63

A Low-Cost Point-of-Care Testing System for Psychomotor Symptoms of Depression Affecting Standing Balance: A Preliminary Study in India.  

PubMed

The World Health Organization estimated that major depression is the fourth most significant cause of disability worldwide for people aged 65 and older, where depressed older adults reported decreased independence, poor health, poor quality of life, functional decline, disability, and increased chronic medical problems. Therefore, the objectives of this study were (1) to develop a low-cost point-of-care testing system for psychomotor symptoms of depression and (2) to evaluate the system in community dwelling elderly in India. The preliminary results from the cross-sectional study showed a significant negative linear correlation between balance and depression. Here, monitoring quantitative electroencephalography along with the center of pressure for cued response time during functional reach tasks may provide insights into the psychomotor symptoms of depression where average slope of the Theta-Alpha power ratio versus average slope of baseline-normalized response time may be a candidate biomarker, which remains to be evaluated in our future clinical studies. Once validated, the biomarker can be used for monitoring the outcome of a comprehensive therapy program in conjunction with pharmacological interventions. Furthermore, the frequency of falls can be monitored with a mobile phone-based application where the propensity of falls during the periods of psychomotor symptoms of depression can be investigated further. PMID:24205436

Dutta, Arindam; Kumar, Robins; Malhotra, Suruchi; Chugh, Sanjay; Banerjee, Alakananda; Dutta, Anirban

2013-01-01

64

A Low-Cost Point-of-Care Testing System for Psychomotor Symptoms of Depression Affecting Standing Balance: A Preliminary Study in India  

PubMed Central

The World Health Organization estimated that major depression is the fourth most significant cause of disability worldwide for people aged 65 and older, where depressed older adults reported decreased independence, poor health, poor quality of life, functional decline, disability, and increased chronic medical problems. Therefore, the objectives of this study were (1) to develop a low-cost point-of-care testing system for psychomotor symptoms of depression and (2) to evaluate the system in community dwelling elderly in India. The preliminary results from the cross-sectional study showed a significant negative linear correlation between balance and depression. Here, monitoring quantitative electroencephalography along with the center of pressure for cued response time during functional reach tasks may provide insights into the psychomotor symptoms of depression where average slope of the Theta-Alpha power ratio versus average slope of baseline-normalized response time may be a candidate biomarker, which remains to be evaluated in our future clinical studies. Once validated, the biomarker can be used for monitoring the outcome of a comprehensive therapy program in conjunction with pharmacological interventions. Furthermore, the frequency of falls can be monitored with a mobile phone-based application where the propensity of falls during the periods of psychomotor symptoms of depression can be investigated further. PMID:24205436

Dutta, Arindam; Kumar, Robins; Malhotra, Suruchi; Chugh, Sanjay; Banerjee, Alakananda; Dutta, Anirban

2013-01-01

65

VISUALIZATION OF FREEZING DAMAGE  

Microsoft Academic Search

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

HARVEY BANK; PETER MAZUR

1973-01-01

66

To freeze or not to freeze: adaptations for overwintering by hatchlings of the North American painted turtle.  

PubMed

Many physiologists believe that hatchling painted turtles (Chrysemys picta) provide a remarkable, and possibly unique, example of 'natural freeze-tolerance' in an amniotic vertebrate. However, the concept of natural freeze-tolerance in neonatal painted turtles is based on results from laboratory studies that were not placed in an appropriate ecological context, so the concept is suspect. Indeed, the weight of current evidence indicates that hatchlings overwintering in the field typically withstand exposure to ice and cold by avoiding freezing altogether and that they do so without benefit of an antifreeze to depress the equilibrium freezing point for bodily fluids. As autumn turns to winter, turtles remove active nucleating agents from bodily fluids (including bladder and gut), and their integument becomes a highly efficient barrier to the penetration of ice into body compartments from frozen soil. In the absence of a nucleating agent or a crystal of ice to 'catalyze' the transformation of water from liquid to solid, the bodily fluids remain in a supercooled, liquid state. The supercooled animals nonetheless face physiological challenges, most notably an increased reliance on anaerobic metabolism as the circulatory system first is inhibited and then caused to shut down by declining temperature. Alterations in acid/base status resulting from the accumulation of lactic acid may limit survival by supercooled turtles, and sublethal accumulations of lactate may affect behavior of turtles after the ground thaws in the spring. The interactions among temperature, circulatory function, metabolism (both aerobic and anaerobic), acid/base balance and behavior are fertile areas for future research on hatchlings of this model species. PMID:15277545

Packard, Gary C; Packard, Mary J

2004-08-01

67

Validity of a portable urine refractometer: the effects of sample freezing.  

PubMed

The use of portable urine osmometers is widespread, but no studies have assessed the validity of this measurement technique. Furthermore, it is unclear what effect freezing has on osmolality. One-hundred participants of mean (±SD) age 25.1 ± 7.6 years, height 1.77 ± 0.1 m and weight 77.1 ± 10.8 kg provided single urine samples that were analysed using freeze point depression (FPD) and refractometry (RI). Samples were then frozen at -80°C (n = 81) and thawed prior to re-analysis. Differences between methods and freezing were determined using Wilcoxon's signed rank test. Relationships between measurements were assessed using intraclass correlation coefficients (ICC) and typical error of estimate (TE). Osmolality was lower (P = 0.001) using RI (634.2 ± 339.8 mOsm · kgH2O(-1)) compared with FPD (656.7 ± 334.1 mOsm · kgH2O(-1)) but the TE was trivial (0.17). Freezing significantly reduced mean osmolality using FPD (656.7 ± 341.1 to 606.5 ± 333.4 mOsm · kgH2O(-1); P < 0.001), but samples were still highly related following freezing (ICC, r = 0.979, P < 0.001, CI = 0.993-0.997; TE = 0.15; and r=0.995, P < 0.001, CI = 0.967-0.986; TE = 0.07 for RI and FPD respectively). Despite mean differences between methods and as a result of freezing, such differences are physiologically trivial. Therefore, the use of RI appears to be a valid measurement tool to determine urine osmolality. PMID:23205563

Sparks, S Andy; Close, Graeme L

2013-01-01

68

Rapid determination of vial heat transfer parameters using tunable diode laser absorption spectroscopy (TDLAS) in response to step-changes in pressure set-point during freeze-drying.  

PubMed

The purpose of this study was to perform a rapid determination of vial heat transfer parameters, that is, the contact parameter K(cs) and the separation distance l(v), using the sublimation rate profiles measured by tunable diode laser absorption spectroscopy (TDLAS). In this study, each size of vial was filled with pure water followed by a freeze-drying cycle using a LyoStar II dryer (FTS Systems) with step-changes of the chamber pressure set-point at to 25, 50, 100, 200, 300, and 400 mTorr. K(cs) was independently determined by nonlinear parameter estimation using the sublimation rates measured at the pressure set-point of 25 mTorr. After obtaining K(cs), the l(v) value for each vial size was determined by nonlinear parameter estimation using the pooled sublimation rate profiles obtained at 25 to 400 mTorr. The vial heat transfer coefficient K(v), as a function of the chamber pressure, was readily calculated, using the obtained K(cs) and l(v) values. It is interesting to note the significant difference in K(v) of two similar types of 10 mL Schott tubing vials, primary due to the geometry of the vial-bottom, as demonstrated by the images of the contact areas of the vial-bottom. PMID:18683861

Kuu, Wei Y; Nail, Steven L; Sacha, Gregory

2009-03-01

69

Freezing Combination Main Dishes  

E-print Network

Making your own frozen prepared foods can be economical. You can cook enough for several meals with little extra effort when you have the time. For best results, remember that freezing maintains, but does not improve, quality. Use only fresh, high-quality food ingredients. Underripe fruits and vegetables lack flavor, and overripe ones are flat and tough, or soft and mushy after freezing. Meat or poultry that is tender before freezing will stay tender after freezing if it is properly prepared, packaged, frozen, and stored. Cleanliness Observe strict cleanliness in preparing food for the home freezer. Freezer temperatures of 0 degrees F or below do not kill bacteria in food; they simply stop bacteria from multiplying. After the frozen food is thawed, bacteria will grow and multiply again. Strict cleanliness keeps the number of bacteria at a minimum before foods are frozen. Foods to Use and Foods to Avoid You may use many of your own favorite recipes for freezing. Prepare the food in the usual way. Cook thoroughly but do not overcook. There may be further cooking when reheated. Foods That Freeze Well • Cooked chicken or turkey in casseroles. • Stews and goulashes made with beef, lamb, pork, or veal. Most vegetables used in these combination dishes, such as peas, carrots, celery, or small quantities of onion also freeze well. However, potatoes may not be satisfactory. • Baked meat loaf. • Cooked dried beans, such as bean soup and baked beans. Because freezing softens beans somewhat, cook until barely tender for best quality. Limit storage time to two weeks if seasoned with ham or bacon. Foods That Do Not Freeze Well The flavor and texture of some foods become poor during freezing. Avoid using these foods. • Cooked egg white toughens. • Mature potatoes which tend to disintegrate, become watery, or darken. New potatoes are better. • Fried foods tend to lose crispness and become soggy. • Avoid freezing cured meats; salt hastens rancidity. • Fresh salad greens, raw tomatoes, raw apples and grapes become soft, soggy, and mushy.

unknown authors

70

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

71

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

72

Freeze-Thaw  

Microsoft Academic Search

Although attempting to consider the impact of freeze-thaw, the monitoring of associated thermal conditions must, effectively,\\u000a be context free. This is important for several reasons. First, although freeze-thaw is being evaluated, data must be of a\\u000a nature that also allows determination of the spatial and temporal role of other processes. Second, by being ‘holistic’ rather\\u000a than (assumed) ‘specific’ in character

Kevin Hall

73

Two-dimensional freezing criteria for crystallizing colloidal monolayers  

SciTech Connect

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 Loewen-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; Han Yilong [Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay (Hong Kong); Alsayed, Ahmed M. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd St., Philadelphia, Pennsylvania 19104 (United States); Complex Assemblies of Soft Matter, CNRS/UPENN/Rhodia UMI 3254, Bristol, Pennsylvania 19007 (United States); Yodh, Arjun G. [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd St., Philadelphia, Pennsylvania 19104 (United States)

2010-04-21

74

Report to the CCT on COOMET comparison COOMET.T-K3.1 (previously COOMET.T-S1): Key regional comparison of the national standards of temperature in the range from the triple point of water to the freezing point of zinc  

NASA Astrophysics Data System (ADS)

In the framework of the CIPM MRA, a first COOMET comparison "Comparison of the ITS-90 realizations in the range from 0.01 °C to 429.7485 °C (from the triple point of water to the freezing point of zinc)", registered in the KCDB under the identifier "COOMET.T-K3", was carried out in 2005-2007. Four national metrology institutes took part in this comparison: VNIIM (Russian Federation), SMU (Slovakia), BelGIM (Republic of Belarus) and NSC IM (Ukraine), and two of them (VNIIM and SMU) ensured the linkage with key comparisons CCT-K3 and CCT-K4, in order to disseminate the metrological equivalence to the measurement standards of NSC IM and BelGIM. NSC IM, however, had to withdraw its results, and at the meeting of Technical Committee T-10 of COOMET it was decided to carry out a supplementary bilateral comparison between VNIIM and the NSC IM for realization of the ITS-90 in the same range of temperature. This was registered in the KCDB under the identifier COOMET.T-S1 and measurements were performed in 2008-2009. From the results presented in this report, it is possible to draw the conclusion that the COOMET supplementary comparison COOMET.T-S1 demonstrates the CMC uncertainties claimed by the NSC IM for the melting point of gallium 0.236 mK (k = 2), and the freezing points of indium 1.040 mK (k = 2), tin 0.858 mK (k = 2) and zinc 0.944 mK (k = 2). In September 2012 the Working Group on key Comparisons (WG 7) of the CCT upgraded this comparison to a COOMET key comparison of the 'CCT-K3' type. It is now identified as COOMET.T-K3.1. In April 2013 this report was superseded by item 03006 in the Technical Supplement of 2013. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Pokhodun, A. I.

2010-01-01

75

Atmosphere-ground modelling of freeze and thaw processes in permafrost regions  

NASA Astrophysics Data System (ADS)

The aim of this proposed project is to realistically simulate the water and energy exchange processes between atmosphere and ground in permafrost regions by using a coupled soil-atmosphere model system. The project will be focused on freezing and thawing processes of the ground, in particular permafrost degradation processes such as changes in the active layer thickness. The coupled model system consists of the non-hydrostatic mesoscale model KAMM (Karlsruhe Atmospheric Mesoscale Model) and the soil vegetation atmosphere transport (SVAT) model VEG3D, recently extended to incorporate explicit treatment of the snow cover evolution. In order to simulate the evolution of frozen ground and to address permafrost specific processes, the SVAT model has to be extended to incorporate the occurrence of frozen water. Parameterisations for processes associated with freezing and thawing, such as freezing point depression and changes in unfrozen water circulation will be included. Model validation will be performed using data sets from different permafrost sites, including monitoring data of ground temperature, soil water content and standard meteorological parameters. Model simulations will be conducted on different temporal and spatial scales, especially for comparative analyses of similar atmospheric episodes in different Arctic and Alpine regions.

Hauck, C.; Kneisel, C.; Kottmeier, C.

2003-04-01

76

Ultrasound-Assisted Freezing  

NASA Astrophysics Data System (ADS)

Freezing is a well-known preservation method widely used in the food industry. The advantages of freezing are to a certain degree counterbalanced by the risk of damage caused by the formation and size of ice crystals. Over recent years new approaches have been developed to improve and control the crystallization process, and among these approaches sonocrystallization has proved to be very useful, since it can enhance both the nucleation rate and the crystal growth rate. Although ultrasound has been successfully used for many years in the evaluation of various aspects of foods and in medical applications, the use of power ultrasound to directly improve processes and products is less popular in food manufacturing. Foodstuffs are very complex materials, and research is needed in order to define the specific sound parameters that aid the freezing process and that can later be used for the scale-up and production of commercial frozen food products.

Delgado, A. E.; Sun, Da-Wen

77

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

78

Freeze Branding Horses  

E-print Network

Freeze branding of horses has many advantages. It is safe, economical, simple to do and relatively painless. It can be done on horses of any age and does not damage the horse's hide. This publication gives complete, step-by-step instructions...

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

2001-06-29

79

Cryogenic freezing system  

SciTech Connect

The operation of a prior art freezer installation for freezing food can be improved by: providing air curtains at the doors of the freezer; using a pulse bag filter for separating ice from the air leaving the freezer; and ensuring that the air leaving the freezer is colder than -800 F.

Prentice, A.L.

1982-03-02

80

Freezing Index Maps of Maine.  

National Technical Information Service (NTIS)

The depth of frost penetration can be calculated by means of the modified Berggren formula whose dependent variables are various soils characteristics and air freezing index. Because the last comprehensive study of the distribution of freezing indexes in ...

N. Bigelow

1969-01-01

81

Freezing Poultry for Home Use  

E-print Network

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

Davis, Michael

2006-08-31

82

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/ ...

83

Major depression  

MedlinePLUS

... major; Depression - clinical; Clinical depression; Unipolar depression; Major depressive disorder ... Doctors do not know the exact causes of depression. It is believed ... responsible. This may be due to a problem with your genes. Or ...

84

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

85

NATURAL FREEZING SURVIVAL IN ANIMALS  

Microsoft Academic Search

Natural freeze-tolerance supports the winter survival of many animals including numerous terrestrial insects, many intertidal marine invertebrates, and selected species of terrestrially hibernating amphibians and reptiles. Freeze-tolerant an- imals typically endure the conversion of 50% or more of total body water into extracellular ice and employ a suite of adaptations that counter the negative con- sequences of freezing. Specific adaptations

Kenneth B. Storey; Janet M. Storey

1996-01-01

86

Winter Depression  

NSDL National Science Digital Library

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

87

Comp aratrve Ultrastructure of Fat Body Cells of Freeze-susceptible and Freeze-tolerant Eurosta solidaginis Larvae After Chemical Fixation and High Pressure Freezing  

Microsoft Academic Search

Cold-hard- ening includes the elevation of the supercooling point, the temperature at which body water spontaneously freezes, and the accumulation of the low-molecular-mass cryoprotectants, glycerol, sorbitol and trehalose. Although it is generally believed that freezing survival is only possible if the ice lattice is restricted to the extracellular space, the larval fat body cells survive intracellular ice formation. Fat body

R. TODD MORASON; ALLAN L. ALLENSPACH; RICHARD E. LEE JR

88

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

89

Inactivation of Kudoa septempunctata in Olive Flounder Meat by Liquid Freezing.  

PubMed

Kudoa septempunctata in olive flounder meat was inactivated using 3 distinct freezing methods? liquid freezing for 5 min, air blast freezing at ?30? for 5 h, and ?80? for 1 h. The fracture curve of olive flounder meat subjected to liquid freezing resembled that of meat stored at 4?, indicating that the structure of olive flounder muscle was well preserved. In contrast, air blast freezing induced the disappearance of the fracture point in the fracture curve, indicating that there was deterioration in the meat quality. Liquid freezing preserved the transparency of olive flounder meat to the same degree as that of meat stored at 4°C. However, air blast freezing induced meat cloudiness. These results indicate that liquid freezing can be used for K. septempunctata inactivation without affecting the meat quality. PMID:25252645

Ohnishi, Takahiro; Akuzawa, Sayuri; Furusawa, Hiroko; Yoshinari, Tomoya; Kamata, Yoichi; Sugita-Konishi, Yoshiko

2014-01-01

90

Seasonal accumulation of acetylated triacylglycerols by a freeze-tolerant insect.  

PubMed

Most animals store energy as long-chain triacylglycerols (lcTAGs). Trace amounts of acetylated triacylglycerols (acTAGs) have been reported in animals, but are not accumulated, likely because they have lower energy density than lcTAGs. Here we report that acTAGs comprise 36% of the neutral lipid pool of overwintering prepupae of the goldenrod gall fly, Eurosta solidaginis, while only 17% of the neutral lipid pool is made up of typical lcTAGs. These high concentrations of acTAGs, present only during winter, appear to be synthesized by E. solidaginis and are not found in other freeze-tolerant insects, nor in the plant host. The mixture of acTAGs found in E. solidaginis has a significantly lower melting point than equivalent lcTAGs, and thus remains liquid at temperatures at which E. solidaginis is frozen in the field, and depresses the melting point of aqueous solutions in a manner unusual for neutral lipids. We note that accumulation of acTAGs coincides with preparation for overwintering and the seasonal acquisition of freeze tolerance. This is the first observation of accumulation of acTAGs by an animal, and the first evidence of dynamic interconversion between acTAGs and lcTAGs during development and in response to stress. PMID:24790101

Marshall, Katie E; Thomas, Raymond H; Roxin, Aron; Chen, Eric K Y; Brown, Jason C L; Gillies, Elizabeth R; Sinclair, Brent J

2014-05-01

91

Postpartum Depression  

MedlinePLUS

... for herself or her family. What is postpartum depression? Postpartum depression is a mood disorder that can ... for themselves or for others. What causes postpartum depression? Postpartum depression does not have a single cause, ...

92

Postpartum Depression  

MedlinePLUS

... 2 weeks without any treatment. What is postpartum depression? Women with postpartum depression have intense feelings of sadness, anxiety, or despair ... to do their daily tasks. When does postpartum depression occur? Postpartum depression can occur up to 1 ...

93

Melting point of ice in aqueous saccharide solutions  

NASA Astrophysics Data System (ADS)

The melting point of ice in trehalose and sucrose solutions was measured by in situ observations of a minute ice crystal. It was found that the concentration dependence of the melting point of ice in both trehalose and sucrose solutions was identical. Such a concentration dependence of the melting point was in agreement with the equation of freezing point depression for dilute aqueous solutions up to about 1 molal. In addition, the measured values of the melting point decreased rapidly with an increase in the concentration. These experimental results for an equilibrium state were discussed by comparing them with the results for a nonequilibrium state, i.e., the results obtained for growing ice crystals in saccharide solutions.

Sei, Tadanori; Gonda, Takehiko

2006-07-01

94

A NEW FREEZING-ULTRAMICROTOME  

Microsoft Academic Search

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

H. Moor; K. MtSHLETHALER; H. WALDNER; A. FREY-WYSSLING

1961-01-01

95

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

96

Understanding Slag Freeze Linings  

NASA Astrophysics Data System (ADS)

Slag freeze linings, the formation of protective deposit layers on the inner walls of furnaces and reactors, are increasingly used in industrial pyrometallurgical processes to ensure that furnace integrity is maintained in these aggressive, high-temperature environments. Most previous studies of freeze-linings have analyzed the formation of slag deposits based solely on heat transfer considerations. These thermal models have assumed that the interface between the stationary frozen layer and the agitated molten bath at steady-state deposit thickness consists of the primary phase, which stays in contact with the bulk liquid at the liquidus temperature. Recent experimental studies, however, have clearly demonstrated that the temperature of the deposit/liquid bath interface can be lower than the liquidus temperature of the bulk liquid. A conceptual framework has been proposed to explain the observations and the factors influencing the microstructure and the temperature of the interface at steady-state conditions. The observations are consistent with a dynamic steady state that is a balance between (I) the rate of nucleation and growth of solids on detached crystals in a subliquidus layer as this fluid material moves toward the stagnant deposit interface and (II) the dissolution of these detached crystals as they are transported away from the interface by turbulent eddies. It is argued that the assumption that the interface temperature is the liquidus of the bulk material represents only a limiting condition, and that the interface temperature can be between T liquidus and T solidus depending on the process conditions and bath chemistry. These findings have implications for the modeling approach and boundary conditions required to accurately describe these systems. They also indicate the opportunity to integrate considerations of heat and mass flows with the selection of melt chemistries in the design of future high temperature industrial reactors.

Fallah-Mehrjardi, Ata; Hayes, Peter C.; Jak, Evgueni

2014-08-01

97

Understanding Slag Freeze Linings  

NASA Astrophysics Data System (ADS)

Slag freeze linings, the formation of protective deposit layers on the inner walls of furnaces and reactors, are increasingly used in industrial pyrometallurgical processes to ensure that furnace integrity is maintained in these aggressive, high-temperature environments. Most previous studies of freeze-linings have analyzed the formation of slag deposits based solely on heat transfer considerations. These thermal models have assumed that the interface between the stationary frozen layer and the agitated molten bath at steady-state deposit thickness consists of the primary phase, which stays in contact with the bulk liquid at the liquidus temperature. Recent experimental studies, however, have clearly demonstrated that the temperature of the deposit/liquid bath interface can be lower than the liquidus temperature of the bulk liquid. A conceptual framework has been proposed to explain the observations and the factors influencing the microstructure and the temperature of the interface at steady-state conditions. The observations are consistent with a dynamic steady state that is a balance between (I) the rate of nucleation and growth of solids on detached crystals in a subliquidus layer as this fluid material moves toward the stagnant deposit interface and (II) the dissolution of these detached crystals as they are transported away from the interface by turbulent eddies. It is argued that the assumption that the interface temperature is the liquidus of the bulk material represents only a limiting condition, and that the interface temperature can be between T liquidus and T solidus depending on the process conditions and bath chemistry. These findings have implications for the modeling approach and boundary conditions required to accurately describe these systems. They also indicate the opportunity to integrate considerations of heat and mass flows with the selection of melt chemistries in the design of future high temperature industrial reactors.

Fallah-Mehrjardi, Ata; Hayes, Peter C.; Jak, Evgueni

2014-09-01

98

9 CFR 590.536 - Freezing operations.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Freezing operations. 590...Animal Products FOOD SAFETY AND INSPECTION...Requirements § 590.536 Freezing operations. (a...examination after freezing to determine their fitness for human food. Any such...

2013-01-01

99

9 CFR 590.534 - Freezing facilities.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Freezing facilities. 590.534 ...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Requirements § 590.534 Freezing facilities. (a) Freezing rooms, either on or off...

2013-01-01

100

9 CFR 590.534 - Freezing facilities.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Freezing facilities. 590.534 ...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Requirements § 590.534 Freezing facilities. (a) Freezing rooms, either on or off...

2010-01-01

101

9 CFR 590.534 - Freezing facilities.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Freezing facilities. 590.534 ...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Requirements § 590.534 Freezing facilities. (a) Freezing rooms, either on or off...

2012-01-01

102

9 CFR 590.534 - Freezing facilities.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Freezing facilities. 590.534 ...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Requirements § 590.534 Freezing facilities. (a) Freezing rooms, either on or off...

2011-01-01

103

9 CFR 590.534 - Freezing facilities.  

...2014-01-01 2014-01-01 false Freezing facilities. 590.534 ...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Requirements § 590.534 Freezing facilities. (a) Freezing rooms, either on or off...

2014-01-01

104

9 CFR 590.536 - Freezing operations.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Freezing operations. 590...Animal Products FOOD SAFETY AND INSPECTION...Requirements § 590.536 Freezing operations. (a...examination after freezing to determine their fitness for human food. Any such...

2012-01-01

105

9 CFR 590.536 - Freezing operations.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Freezing operations. 590...Animal Products FOOD SAFETY AND INSPECTION...Requirements § 590.536 Freezing operations. (a...examination after freezing to determine their fitness for human food. Any such...

2010-01-01

106

9 CFR 590.536 - Freezing operations.  

...2014-01-01 false Freezing operations. 590...Animal Products FOOD SAFETY AND INSPECTION...Requirements § 590.536 Freezing operations. (a...examination after freezing to determine their fitness for human food. Any such...

2014-01-01

107

9 CFR 590.536 - Freezing operations.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Freezing operations. 590...Animal Products FOOD SAFETY AND INSPECTION...Requirements § 590.536 Freezing operations. (a...examination after freezing to determine their fitness for human food. Any such...

2011-01-01

108

Freezing in Sealed Capillaries for Preparation of Frozen Hydrated Sections  

PubMed Central

We have investigated the freezing of specimens in a confined volume for preparation of vitreous samples for cryosectioning. With 15% dextran as a cryoprotectant, a sample sealed in a copper tube begins to freeze into crystalline ice when plunged into liquid ethane. Crystallization rapidly causes an increase in the pressure to the point that much of the sample freezes in a vitreous state. We used synchrotron X-ray diffraction of samples frozen with various amounts of dextran to characterize the ice phases and crystal orientation, providing insights on the freezing process. We have characterized cryosections obtained from these samples to explore the optimum amount of cryoprotectant. Images of cryosectioned bacteria frozen with various levels of cryoprotectant illustrate effects of cryoprotectant concentration. PMID:22077543

Yakovlev, Sergey; Downing, Kenneth H.

2014-01-01

109

Caregiver Depression  

MedlinePLUS

... will not sell or share your name. Caregiver Depression Tweet Bookmark this page | Email | Print Many caregivers ... depression See your doctor Treatment Coping Symptoms of depression Caregiving is hard ? and can lead to feelings ...

110

Nuclear freeze: myths and realities  

SciTech Connect

A nuclear freeze would create serious problems for US strategic and political interests, and would not achieve the professed goal of a lower probability of nuclear war. It could increase strategic instability and reinforce the morally questionable Mutual Assured Destruction (MAD) approach of using civilian populations as hostages. Compliance would not be verifiable, and Soviet compliance would be doubtful. A review of the strategic and political implications and the basic assumptions of freeze advocates suggests that the movement has proved useful in forcing advocates of other positions to sharpen and refine their arguments. The challenge for freeze opponents is to make it clear to the public that the proposed freeze would benefit the Soviets and to offer viable alternatives for nuclear policy. 15 references.

Weinrod, W.B.

1983-03-03

111

Freezing times of regularly shaped food items  

Microsoft Academic Search

The freezing of food is one of the most significant applications of refrigeration. In order for freezing operations to be cost-effective, it is necessary to optimally design the refrigeration equipment. This requires estimation of the freezing times of foods. Numerous semianalytical\\/empirical methods for predicting food freezing times have been proposed. The designer of food refrigeration facilities is thus faced with

Bryan R. Becker; Brian A. Fricke

1999-01-01

112

Freezing and ice crystals formed in a cylindrical food model: part I. Freezing at atmospheric pressure  

Microsoft Academic Search

Cylindrical gelatin gels were frozen at atmospheric pressure with different operating conditions (air-blast freezing at different air temperatures and brine freezing). A method to calculate a local freezing rate was proposed to take into account the variation of freezing rate as a function of the radius. A linear evolution of the local freezing rate according to the radius was observed

D Chevalier; A Le Bail; M Ghoul

2000-01-01

113

Seasonal depression  

Microsoft Academic Search

Objective: In DSM-IV, winter seasonal affective disorder (SAD) is classified as a seasonal pattern of recurrent major depressive episodes in winter with full remission of symptoms in summer. However, other groups with “winter depression” have been identified, including patients with incomplete summer remission (ISR) and subsyndromal SAD (sub-SAD, winter depressive symptoms that do not meet criteria for major depression). In

Raymond W Lam; Edwin M Tam; Lakshmi N Yatham; I-Shin Shiah; Athanasios P Zis

2001-01-01

114

Freeze concentration effects on ice (photo) chemical kinetics investigated by UV-Vis spectroscopy  

NASA Astrophysics Data System (ADS)

We will describe the setup of a fiber coupled UV-Vis spectrometer to investigate the chemistry and photochemistry of aqueous solutions before and after freezing. The photochemical degradation of pyranine at the isosbestic point was investigated. Direct photochemical degradation was minor compared to indirect degradation through hydroxyl radical (OH) attack at room temperature. At -10 C indirect OH degradation was increased relative to room temperature studies, and has been attributed to the freeze concentration effect. The reaction of bromate with bromide in the presence of acid to form molecular bromine was investigated. Upon freezing the formation rate of bromine significantly increases, which we attribute to the freeze concentration effect.

Newberg, J. T.; Arble, C.; Zhang, J.

2013-12-01

115

The original Plank equation and its use in the development of food freezing rate predictions  

Microsoft Academic Search

A large number of methods to predict freezing and thawing times for foodstuffs have been proposed. Normally the original Plank equation is used as the starting point, but since this equation does not include the times below and above the freezing itself, several attempts have been made to improve it by adding new terms and parameters, to make it suitable

Miguel López-Leiva; Bengt Hallström

2003-01-01

116

Freezing of 4 He and its liquid-solid interface from density functional theory  

E-print Network

of the crystal growth can be studied over a wide temperature range, in principle down to absolute zero. Helium phenomenon of crystallization waves, i.e., melting-freezing waves which can easily propagate on the liquid freezing in classical systems for a review see, e.g., Refs. 12­14 . The common point of vi

Caupin, Frédéric

117

Freeze-fracture cytochemistry: partition of glycophorin in freeze- fractured human erythrocyte membranes  

PubMed Central

Thin-section and critical-point-dried fracture-labeled preparations are used to determine the distribution and partition of glycophorin- associated wheat germ agglutinin (WGA) binding sites over protoplasmic and exoplasmic faces of freeze-fractured human erythrocyte membranes. Most wheat germ agglutinin binding sites are found over exoplasmic faces. Label is sparse over the protoplasmic faces. These results contrast with previous observations of the partition of band 3 component where biochemical analysis and fracture-label of concanavalin A (Con A) binding sites show preferential partition of this transmembrane protein with the protoplasmic face. Presence of characteristic proportions of WGA and Con A binding sites over each fracture face is interpreted to indicate the operation of a stochastic process during freeze-fracture. This process appears modulated by the relative expression of each transmembrane protein at either surface as well as by their association to components of the erythrocyte membrane skeleton. PMID:7096449

1982-01-01

118

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

SciTech Connect

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

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

2007-05-17

119

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. PMID:20011523

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

2009-01-01

120

Performance of residential air-to-air heat exchangers during operation with freezing and periodic defrosts  

SciTech Connect

In a laboratory study of the performance of residential air-to-air heat exchangers during operation with freezing and periodic defrosts, freezing caused the temperature efficiency of a cross-flow heat exchanger to decrease at a rate ranging from 1.5 to 13.2 percentage points per hour. Much smaller rates of decrease in temperature efficiency, 0.6 to 2.0 percentage points per hour, occurred during tests with a counterflow heat exchanger. The rate of decrease in efficiency depended on the airstream temperatures and humidities and the duration of the period of freezing. The amount of time required to defrost the heat exchanger's core was 6 to 26% of the total operating time. The average temperature efficiency for freeze-defrost cycles ranged from 48 to 64% in tests of the cross-flow exchanger and 70 to 82% in tests of the counterflow exchanger. When the frequency and duration of defrosts were nearly optimal, approximately a 10 to 15 percentage point decrease in average temperature efficiency was attributed to the freezing and required defrosts. The results suggested that the rate of performance deterioration due to freezing can be reduced by avoiding small airflow passages that can easily be plugged with ice and by designing the exchanger so that condensed water does not drain toward the cold regions of the core. Based on this investigation, suggestions are made for future experimental studies of freezing and for improved control of freeze-protection systems. 1 reference, 8 figures, 2 tables.

Fisk, W.; Archer, K.; Chant, R.; Hekmat, D.; Offermann, F.; Pedersen, B.

1984-11-01

121

Cytokines, Stress, and Depression  

Microsoft Academic Search

From the data that are reviewed in this volume, several important points emerge: (1) cytokines administered to patients and\\u000a laboratory animals induce symptoms of depression, including, depressed mood, decreased interest in daily activities, anhedonia,\\u000a reduced food intake, sleep disorders, hyperactivity of the HPA axis, and glucocorticoid resistance; (2) exposure to stressors\\u000a can induce the expression of cytokines at the periphery

Robert Dantzer; Emmanuelle E. Wollman; Ljubisa Vitkovic; Raz Yirmiya

122

Energy and its involvement in depression  

E-print Network

depression diagnosis and BDI, an overall exhaustion factor accounted for the majority of variance, 67% and 71% respectively, These analyses suggest that the primary relationship is between energy and depression. This moderating effect is especially... in the DSM-III-R. Based on this description, they rated their depression on a five-point scale from not at all to very depressed. If they expressed that they were moderately or very depressed they were eliminated from the study and presented...

Duncan, Katherine Dusek

2012-06-07

123

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

124

Fuel Cell Freeze Startup and Landscape of FC Freeze Patents  

E-print Network

has a temperature below the freezing temperature of water. The supply of electric current for startup. · Use component/system models to evaluate merits of various solutions from fuel efficiency integrity · Fuel starvation (Elimination of water droplets from flow fields) · Cathode ice formation

125

Postpartum Depression  

MedlinePLUS

... do not need treatment. The symptoms of postpartum depression last longer and are more severe. You may ... treatment right away, often in the hospital. Postpartum depression can begin anytime within the first year after ...

126

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

SciTech Connect

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

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

1996-11-01

127

Understanding Depression  

PubMed Central

To understand the effects of depression on a patient's life, the physician must be aware how depression manifests itself. Somatic tension, strategies to relieve discomfort and social withdrawal must be recognized as symptoms of depression. An awareness of life situations which can give rise to these symptoms, as well as the effect of the physician's own reactions to the patient's depression, are helpful. PMID:21289767

McNair, F. E.

1981-01-01

128

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

129

Time dependence of immersion freezing  

NASA Astrophysics Data System (ADS)

The time dependence of immersion freezing was studied for temperatures between 236 K and 243 K. Droplets with single immersed, size-selected 400 nm and 800 nm kaolinite particles were produced at 300 K, cooled down to supercooled temperatures typical for mixed-phase cloud conditions, and the fraction of frozen droplets with increasing residence time was detected. To simulate the conditions of immersion freezing in mixed-phase clouds we used the Zurich Ice Nucleation Chamber (ZINC) and its vertical extension, the Immersion Mode Cooling chAmber (IMCA). We observed that the frozen fraction of droplets increased with increasing residence time in the chamber. This suggests that there is a time dependence of immersion freezing and supports the importance of a stochastic component in the ice nucleation process. The rate at which droplets freeze was observed to decrease towards higher temperatures and smaller particle sizes. Comparison of the laboratory data with four different ice nucleation models, three based on classical nucleation theory with different representations of the particle surface properties and one singular, suggest that the classical, stochastic approach combined with a distribution of contact angles is able to reproduce the ice nucleation observed in these experiments most accurately. Using the models to calculate the increase in frozen fraction at typical mixed-phase cloud temperatures over an extended period of time, yields an equivalent effect of -1 K temperature shift and an increase in time scale by a factor of ~10.

Welti, A.; Lüönd, F.; Kanji, Z. A.; Stetzer, O.; Lohmann, U.

2012-05-01

130

Ultrasonic monitoring of food freezing  

Microsoft Academic Search

The time of flight of an ultrasonic pulse moving parallel to the direction of heat flux was measured in blocks of food (gelatin, chicken, beef) during freezing. Echoes were recorded from the food surfaces and from the moving ice front within the food. The changing return times of these echoes were used to calculate the percentage of the food frozen

Halldor Sigfusson; Gregory R. Ziegler; John N. Coupland

2004-01-01

131

Performance of residential air-to-air heat exchangers during operation with freezing and periodic defrosts  

Microsoft Academic Search

In a laboratory study of the performance of residential air-to-air heat exchangers during operation with freezing and periodic defrosts, freezing caused the temperature efficiency of a cross-flow heat exchanger to decrease at a rate ranging from 1.5 to 13.2 percentage points per hour. Much smaller rates of decrease in temperature efficiency, 0.6 to 2.0 percentage points per hour, occurred during

W. Fisk; K. Archer; R. Chant; D. Hekmat; F. Offermann; B. Pedersen

1984-01-01

132

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

Microsoft Academic Search

Freeze tolerance is a complex cold-hardiness adaptation that has independently evolved in a diverse group of organisms, including several ectothermic vertebrates. Because little is known about the mechanistic basis for freeze tolerance in reptiles, we compared responses to experimental freezing in winter-acclimatized hatchlings representing nine taxa of temperate North American turtles, including ones that tolerated freezing and others that did

Jon P. Costanzo; Patrick J. Baker; Richard E. Lee Jr

2006-01-01

133

Freezing: an underutilized food safety technology?  

Microsoft Academic Search

Freezing is an ancient technology for preserving foods. Freezing halts the activities of spoilage microorganisms in and on foods and can preserve some microorganisms for long periods of time. Frozen foods have an excellent overall safety record. The few outbreaks of food-borne illness associated with frozen foods indicate that some, but not all human pathogens are killed by commercial freezing

Douglas L. Archer

2004-01-01

134

Freeze\\/thaw power system. [water expansion  

Microsoft Academic Search

A freeze-thaw power cycle is described that includes a piston driven by the expansion power of a fluid such as water in a cyclinder on freezing and the thawing thereof with alternate, rapid freezing and thawing of the fluid by low and high temperature means with heat transfer rates facilitated by the use of heat pipes or tubes or other

1978-01-01

135

Atmospheric Freeze Drying—A Review  

Microsoft Academic Search

This review article focuses on the development of atmospheric freeze drying (AFD): technological aspects, product possibilities, physical properties of products, drying kinetics, modeling, and simulation. The main motivation for developing atmospheric freeze drying as a new drying technology is the desire to reduce the energy consumption compared to vacuum freeze drying while maintaining a high product quality. One technical solution

I. C. Claussen; T. S. Ustad; I. Strømmen; P. M. Walde

2007-01-01

136

Infants of depressed mothers.  

PubMed

Depression is the most frequent psychiatric disorder and has long-term, compromising effects on the mother-infant relationship and the child's development. The infant continuously faces a climate of negative affect that disrupts the interactive experience of the infant and the mother. This article presents findings on the impact of maternal depression on the infant affective state and the specific interactive patterns associated with infant affect regulation. Mother-infant interactions were studied using microanalytic, second-by-second methods in the laboratory and also by using naturalistic home observations. The empirical findings highlight the impact of maternal depression on the infant affective state and on the capacity for repairing states of miscoordination. The impact is seen not only in severely and acutely depressed mothers, but in mothers who have only high levels of depressive symptoms. These infants develop negative affective states that bias their interactions with others and exacerbate their affective problems. Further findings with regard to gender-specific effects show that male infants are more vulnerable than female infants to maternal depression. The findings point out the need for therapeutic interventions that focus on the mother-infant dyad and infant affective state in the treatment of maternal depression. PMID:19373622

Tronick, Edward; Reck, Corrina

2009-01-01

137

Biotechnological applications of plant freezing associated Ghislain Breton1  

E-print Network

, freezing tolerance, frozen food, genetic engineering, organ preservation, osmoprotectants, osmotic stress57 Biotechnological applications of plant freezing associated proteins Ghislain Breton1 , Jean and freezing conditions. The identification of these freezing tolerance associated proteins and the elucidation

Sarhan, Fathey

138

Real Stories of Depression  

MedlinePLUS

... Information > Depression > Men and Depression Real Stories of Depression More Public Service Announcements (PSAs) Signs and Symptoms ... Sierra , Trauma and Recovery Specialist Share Men and Depression Depression in Men Signs & Symptoms Depression Treatment Getting ...

139

Psychosocial treatments for adolescent depression  

Microsoft Academic Search

Major Depressive Disorders affect between 2% and 5% of adolescents at any one point in time. Depression in adolescence is associated with serious psychosocial deficits and has negative effects on functioning during young adulthood. Starting with the pioneering work of Lenore Butler and her colleagues, many psychosocial interventions have been developed and studied, with generally positive results. On the basis

Peter M Lewinsohn; Gregory N Clarke

1999-01-01

140

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

141

Differentiation between major and minor depression.  

PubMed

Though the concept of Major Depression was generated by clinicians using depressed inpatients as models, a polydiagnostic study in 600 psychiatric inpatients with heterogenous psychological disturbances revealed that all six competing operational definitions of Major Depression (including DSM-III-R and ICD-10) were too restrictive to serve as a general concept of depression. Another polydiagnostic study in 500 primary care outpatients showed that more than two-thirds of all non-chronic depressed cases were below the severity threshold of Major Depression: these patients are classified as Depression Not Otherwise Specified (NOS) by DSM-III-R. Loosening of the over-restrictive time criteria would broaden the concept of Major Depression so as to meet the requirements of a general concept of depression, while the definition of Minor Depression below the threshold of Major Depression would add to a reduction of cases of NOS Depression by more than 80%. For the evaluation of antidepressant drugs in outpatient samples, we propose that patients with these modified definitions of Major and Minor Depression be included, provided they meet a minimum severity criterion of 13 or more points on the Hamilton Depression Scale; four-fifths of the modified Major Depression group and one-third of the Minor Depression group do in fact meet this criterion. PMID:1546147

Philipp, M; Delmo, C D; Buller, R; Schwarze, H; Winter, P; Maier, W; Benkert, O

1992-01-01

142

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

143

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

144

Exact theory of freeze out  

E-print Network

By considering the kinetic equations for the relic particles and the bath particles supposed in thermal and chemical equilibrium in the early Universe, we show that the problem of finding the present relic abundance is exactly defined by a system of two equations, the usual Boltzmann equation and a new one previously not recognized. The analytical solution of the latter gives the abundance down to a matching temperature that can be identified with freeze out temperature $x_f=m/T_f$, while the usual Boltzmann equation is valid only for $x \\ge x_f$. The dependence of the present relic abundance on the abundance at an intermediate temperature is an exact result and not the consequence of the so called freeze out approximation. We also suggest an analytical approximation that furnishes the relic abundance accurate at the level of $1\\%-2\\%$ in the case of $S$-wave and $P$-wave scattering cross sections.

Cannoni, Mirco

2014-01-01

145

Exact theory of freeze out  

E-print Network

By considering the kinetic equations for the relic particles and the bath particles supposed in thermal and chemical equilibrium in the early Universe, we show that the problem of finding the present relic abundance is exactly defined by a system of two equations, the usual Boltzmann equation and a new one previously not recognized. The analytical solution of the latter gives the abundance down to a matching temperature that can be identified with freeze out temperature $x_f=m/T_f$, while the usual Boltzmann equation is valid only for $x \\ge x_f$. The dependence of the present relic abundance on the abundance at an intermediate temperature is an exact result and not the consequence of the so called freeze out approximation. We also suggest an analytical approximation that furnishes the relic abundance accurate at the level of $1\\%-2\\%$ in the case of $S$-wave and $P$-wave scattering cross sections.

Mirco Cannoni

2014-07-15

146

Commercial Application of Freeze Crystallization  

E-print Network

Comparison The curve for evaporation represenls the installed cost for a multiple effecl, steam driven system. Our cost estimates indicate Ihe total installed capital cost for a mechanical vapor recompression unit would be somewhat higher. We expect... will lower substantially in future generation designs, perhaps even approaching the cost of mechanical vapor recompression evaporation. POWER CONSUMPTION An adherent advantage of freeze crystallization is the low phase change energy required...

Gorgol, R. G.

147

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. PMID:21536169

Park, Mijung; Unutzer, Jurgen

2011-01-01

148

Control of glycerol production by rainbow smelt ( Osmerus mordax) to provide freeze resistance and allow foraging at low winter temperatures  

Microsoft Academic Search

The rainbow smelt (Osmerus mordax) is a small anadromous fish that actively feeds under the ice at temperatures as low as the freeze point of seawater. Freezing is avoided through the production of both non-colligative antifreeze protein (AFP) and glycerol that acts in a colligative manner. Glycerol is constantly lost across the gills and skin, thus glycerol production must continue

William R. Driedzic; K. Vanya Ewart

2004-01-01

149

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

150

Depression (PDQ)  

MedlinePLUS

... cause depression include the following: A personal or family history of depression or suicide . A personal history of alcoholism or drug abuse . A personal history of mental problems. A weak social support system (not being married, having few family members or friends, having a job where you ...

151

Postpartum depression  

Microsoft Academic Search

The aim of this study was to explore the lived experiences of postpartum depression among the Middle Eastern women living in Sydney, Australia. A phenomenologic research design was used to conduct in-depth, unstructured interviews with a purposive sample of 45 mothers who had experienced postpartum depression. The interviews were conducted in the mothers’ homes. Transcriptions of these interviews were analyzed

Violeta Lopez Nahas; Sharon Hillege; Nawal Amasheh

1999-01-01

152

Postpartum Depression  

MedlinePLUS

... within 10 days after delivery. What is postpartum depression? Some womens have more severe symptoms of the baby blues ... have any of the other symptoms of postpartum depression, remember that many other women have had the same experience. You're not " ...

153

Metabolic Activity of Permafrost Bacteria below the Freezing Point  

Microsoft Academic Search

Metabolic activity was measured in the laboratory at temperatures between 5 and 220°C on the basis of incorporation of 14 C-labeled acetate into lipids by samples of a natural population of bacteria from Siberian permafrost (permanently frozen soil). Incorporation followed a sigmoidal pattern similar to growth curves. At all temperatures, the log phase was followed, within 200 to 350 days,

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

2000-01-01

154

Transverse freezing of thin liquid films  

NASA Astrophysics Data System (ADS)

A pair of coupled non-linear partial differential equations is derived using lubrication theory that govern the morphology of a thin, liquid film of a pure and a binary metal alloy, bounded by the liquid's solid phase and a passive gas phase. The analysis is motivated by the directional freezing of metallic foams, and is a first attempt to model transverse freezing in thin films that form in foam networks, but also applies to thin film layers in general. Both the no-slip crystal-melt and the free melt-gas interfaces are deformable. The governing pair of non-linear differential equations for the most general case incorporate crystal-melt and melt-gas surface tension, latent heat, heat transfer, volume change, molecular interactions, thermocapillary and dilute phase concentration effects. Linear analysis of a uniform film reveals a variety of instabilities. A unique wavenumber is selected at the onset of instability in the case of an applied temperature gradient with vanishing crystal-melt surface tension. This system reproduces the isothermal result for a rigid solid-liquid interface in which a band of wavenumbers is unstable. A new long-wave instability has been identified, for the case with CM surface tension, that is due to the coupling of the interfaces. Numerical solutions of the fully non-linear system provide film evolution and rupture times, and show that, near the critical conditions, rupture can occur by the growth of standing or traveling waves. The numerics also reveals complex non-linear interactions between unstable modes. It is found that for most unstable initial conditions, the crystal-melt interface retreats by melting away from the tip region of the encroaching melt-gas interface due to a rise in heat flux as the film thins near the rupture point.

Beerman, Michael

155

Predicting Freezing for Some Repulsive Potentials  

SciTech Connect

We propose a simple method to approximately predict the freezing (fluid-solid) phase transition in systems of particles interacting via purely repulsive potentials. The method is based on the striking universality of the freezing curve for the model Yukawa and inverse-power-law interactions. This method is applied to draw an exemplary phase diagram of complex plasmas. We suggest that it can also be used to locate freezing transition in other substances with similar properties of interaction.

Khrapak, S. A.; Morfill, G. E. [Max-Planck-Institut fuer extraterrestrische Physik, D-85741 Garching (Germany)

2009-12-18

156

Mechanism of freeze-drying drug nanosuspensions.  

PubMed

Drug nanoparticles prepared in a liquid medium are commonly freeze-dried for the preparation of an oral dosage in solid dosage form. The freezing rate is known to be a critical parameter for redispersible nanoformulations. However, there has been controversy as to whether a fast or slow freezing rate prevents irreversible aggregation. A systematic investigation is presented herein regarding the effect of both the molecular weight of the cryoprotectant and the freezing rate in order to elucidate the mechanism underlying irreversible aggregation. It was found that irreversible aggregation occurred during drying rather than freezing, although a proper freezing rate is critical. A more homogeneous distribution of the cryoprotectant and drug nanoparticles led to more redispersible powders. Thus, keeping the local concentration distribution of the nanoparticles and cryoprotectant fixed during the freezing step plays a critical role in how the freezing rate affects the redispersibility. The kinetic approach of excluding the tendency of ice crystal growth permitted an explanation of the controversial results. This study will facilitate an in-depth understanding of the aggregation process of nanoparticles or proteins during freeze-drying. PMID:22877696

Chung, Nae-Oh; Lee, Min Kyung; Lee, Jonghwi

2012-11-01

157

Reptile freeze tolerance: metabolism and gene expression.  

PubMed

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

Storey, Kenneth B

2006-02-01

158

Depression and Chronic Pain  

MedlinePLUS

... difficult, so proper treatment is important. What is depression? Major depressive disorder, or depression, is a serious ... older have depression. 1 Signs and Symptoms of Depression Ongoing sad, anxious, or empty feelings Feeling hopeless ...

159

Depression and Stroke  

MedlinePLUS

... difficult, so proper treatment is important. What is depression? Major depressive disorder, or depression, is a serious ... older have depression. 1 Signs and Symptoms of Depression Ongoing sad, anxious, or empty feelings Feeling hopeless ...

160

Depression and Cancer  

MedlinePLUS

... difficult, so proper treatment is important. What is depression? Major depressive disorder, or depression, is a serious ... older have depression. 1 Signs and Symptoms of Depression Ongoing sad, anxious, or empty feelings Feeling hopeless ...

161

Depression and Smoking  

MedlinePLUS

Home » Tools » Depression Basics » Depression and Smoking Depression and Smoking Why is depression more common in smokers? Nobody knows for sure why smokers are more likely to have depression than non- ...

162

Depression and Diabetes  

MedlinePLUS

... difficult, so proper treatment is important. What is depression? Major depressive disorder, or depression, is a serious ... older have depression. 1 Signs and Symptoms of Depression Ongoing sad, anxious, or empty feelings Feeling hopeless ...

163

Depression and Heart Disease  

MedlinePLUS

... difficult, so proper treatment is important. What is depression? Major depressive disorder, or depression, is a serious ... older have depression. 1 Signs and Symptoms of Depression Ongoing sad, anxious, or empty feelings Feeling hopeless ...

164

Suicide and Depression  

MedlinePLUS

... symptoms of depression and the warning signs of suicide help people understand that depression and related depressive illnesses are both preventable and treatable. What causes a depressive illness? Depressive illnesses are biological illnesses ...

165

Reliable Change in Depression during Behavioral Weight Loss Treatment among Women with Major Depression  

PubMed Central

Although behavioral weight loss interventions generally have been shown to improve depressive symptoms, little is known as to whether some people with major depressive disorder experience worsening of depression during a weight loss intervention. We examined rates and predictors of change in depression symptoms among 148 obese women with major depressive disorder who participated in a trial comparing depression treatment plus behavioral weight loss treatment (Behavioral Activation; BA) to behavioral weight loss treatment alone (Lifestyle Intervention; LI). A statistically reliable change in depression was calculated as ? 9 points on the Beck Depression Inventory in this sample. At 6 months, 73% of participants in BA and 54% of participants in LI showed reliable improvement in depression symptoms and 1.5% of participants in BA and 1.3% of participants in LI showed reliable worsening in depression symptoms. Rates of reliable change were similar at 12 months. Participants who experienced reliable improvement in depression lost significantly more weight than those who did not in both conditions. In the LI condition, baseline psychiatric variables and change in physical activity during treatment were also related to reliable improvement in depression. We found no evidence for an iatrogenic effect of behavioral weight loss treatment on depressive symptoms among obese women with major depressive disorder; rather, behavioral weight loss treatment appears to be associated with significant concurrent improvement in depression. Even greater rates of reliable improvement were observed when depression treatment was added to weight loss treatment. PMID:23592677

Busch, Andrew M.; Whited, Matthew C.; Appelhans, Bradley M.; Schneider, Kristin L.; Waring, Molly E.; DeBiasse, Michele A.; Oleski, Jessica L.; Crawford, Sybil L.; Pagoto, Sherry L.

2012-01-01

166

Food freezing with simultaneous surface dehydration: approximate prediction of freezing time  

Microsoft Academic Search

Freezing of unpackaged foods induces mass transfer in the form of surface ice sublimation, which in turn modifies heat transfer conditions. At present there are no simplified methods for predicting freezing times when surface dehydration occurs. This paper uses a previously developed model for the simulation of simultaneous heat and mass transfer during food freezing and storage to generate a

Laura A. Campañone; Viviana O. Salvadori; Rodolfo H. Mascheroni

2005-01-01

167

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

168

Major depression.  

PubMed

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

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

2014-09-01

169

Water sorption and time-dependent crystallization behaviour of freeze-dried lactose–salt mixtures  

Microsoft Academic Search

Water sorption properties of freeze-dried lactose, lactose\\/CaCl2, lactose\\/NaCl, lactose\\/MgCl2, and lactose\\/KCl mixtures in their molar ratio of (9:1) were investigated. Brunauer–Emmett–Teller (BET) and Guggenheim–Anderson–de Boer (GAB) models were used to model water sorption properties. Water is known to function as a plasticizer, depressing the glass transition and facilitating crystallization. Crystallization in the present study resulted in loss of sorbed water

A. M. Elmonsef Omar; Yrjö H. Roos

2007-01-01

170

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

171

Managing Depression  

MedlinePLUS

... Fatigue • Sadness, depressed mood • Loss of appetite with weight loss • No interest or pleasure in daily activities • Withdrawal from family and friends • Sleep problems • Feelings of worthlessness, hopelessness, guilt • Difficulty focusing ...

172

Innovation in Monitoring Food Freeze Drying  

Microsoft Academic Search

This paper aims to extend the field of application of the pressure rise, test technique, from freeze drying of pharmaceutical or biological products in vials to freeze drying of liquids or foodstuff in trays. The proposed method, which is based on DPE algorithm, has been adapted to monitor the drying of liquids in trays and of individually quick frozen products.

Roberto Pisano; Antonello A. Barresi; Davide Fissore

2011-01-01

173

Freezing in residential air-to-air heat exchangers: an experimental study  

SciTech Connect

Mechanical ventilation of residences, with heat recovery in air-to-air heat exchangers, is an increasingly common practice. When this technique of ventilation is used in cold climates, however, freezing can occur in the air-to-air heat exchanger and substantially reduce its performance. A laboratory investigation was conducted to determine the indoor and outdoor environmental conditions that lead to freezing, the impact of freezing on performance, and the effect on performance of a common freeze protection strategy based on periodic defrosts. In experiments with three different models of air-to-air heat exchangers, the temperature of the inlet cold airstream at which freezing was initiated ranged from -3/sup 0/C to -12/sup 0/C and varied with the humidity of the inlet warm airstream. Freezing caused the temperature efficiency of a cross-flow heat exchanger to decrease at a rate that ranged from 1.5 to 13.2 percentage points per hour. Small rates of decrease in efficiency (0.6 to 2.0 percentage points per hour) resulted from freezing in a counterflow exchanger. The rate of decrease in efficiency depended on the airstream temperatures and humidities, and the duration of the period of freezing. The amount of time required to defrost the heat exchanger's core was 6 to 26% of the total operating time. The average temperature efficiency for freeze-defrost cycles ranged from 48 to 64 percent in tests of the cross-flow exchanger and 70 to 82 percent in tests of the counterflow exchanger. When the frequency and duration of defrosts were nearly optimal, approximately a ten to fifteen percentage point decrease in average temperature efficiency was attributed to the freezing and required defrosts. The results suggested that the rate of performance deteriorations due to freezing can be reduced by avoiding small airflow passages that can easily be plugged with ice and by designing the exchanger so that condensed water does not drain toward the cold regions of the core.

Fisk, W.J.; Archer, K.M.; Chant, R.E.; Hekmat, D.; Offermann, F.J.; Pedersen, B.S.

1983-09-01

174

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

E-print Network

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

Paris-Sud XI, Université de

175

A Phase-Field Solidification Model of Almost Pure ITS-90 Fixed Points  

NASA Astrophysics Data System (ADS)

A two-dimensional axisymmetric phase-field model of thermo-solutal solidification in freezing-point cells used for calibrating standard platinum resistance thermometers for realization and dissemination of the International Temperature Scale of 1990 is presented. The cell is essentially a graphite crucible containing an ingot of very pure metal (of order 99.9999 %). A graphite tube is inserted along the axis of the ingot to enable immersion of the thermometer in the metal. In this study, the metal is tin (freezing temperature of 231.928° C). During the freezing of these cells, a steady, reproducible temperature is realized, with a defined temperature that can be used to calibrate thermometers with uncertainties {<}1 mK. The model is applied to understand the effect of experimental parameters, such as initiation technique and furnace homogeneity, on the measured freezing curve. Results show that freezing curves whose behavior is consistent with the Scheil theory of solidification can be obtained with a specific furnace temperature profile, and provided that the freeze is of a long duration, the results are consistent with previous one-dimensional models and experiments. Morphological instability is observed with the inner interface initiation technique, causing the interface to adopt a cellular structure. This elevates the measured temperature, in accordance with the Gibbs-Thomson effect. In addition, the influence of initiation techniques on the solidification behavior is examined. The model indicates that an initially smooth inner mantle can `de-wet' from the thermometer well-forming agglomerated solid droplets, following recalescence, under certain conditions. This manifests as a measured temperature depression due to the Gibbs-Thomson effect, with a magnitude of 100 {\\upmu } K to 200 {\\upmu } K in simulations. The temperature rises to that of the stable outer mantle as freezing progresses and the droplets re-melt. It is demonstrated that the effect occurs below a critical mantle thickness. A physical explanation for the origin of the effect is offered showing that it is consistent with solid-state de-wetting phenomena. Consideration is also given to the limitations of the current model configuration.

Large, M. J.; Pearce, J. V.

2014-08-01

176

A Phase-Field Solidification Model of Almost Pure ITS-90 Fixed Points  

NASA Astrophysics Data System (ADS)

A two-dimensional axisymmetric phase-field model of thermo-solutal solidification in freezing-point cells used for calibrating standard platinum resistance thermometers for realization and dissemination of the International Temperature Scale of 1990 is presented. The cell is essentially a graphite crucible containing an ingot of very pure metal (of order 99.9999 %). A graphite tube is inserted along the axis of the ingot to enable immersion of the thermometer in the metal. In this study, the metal is tin (freezing temperature of ). During the freezing of these cells, a steady, reproducible temperature is realized, with a defined temperature that can be used to calibrate thermometers with uncertainties mK. The model is applied to understand the effect of experimental parameters, such as initiation technique and furnace homogeneity, on the measured freezing curve. Results show that freezing curves whose behavior is consistent with the Scheil theory of solidification can be obtained with a specific furnace temperature profile, and provided that the freeze is of a long duration, the results are consistent with previous one-dimensional models and experiments. Morphological instability is observed with the inner interface initiation technique, causing the interface to adopt a cellular structure. This elevates the measured temperature, in accordance with the Gibbs-Thomson effect. In addition, the influence of initiation techniques on the solidification behavior is examined. The model indicates that an initially smooth inner mantle can `de-wet' from the thermometer well-forming agglomerated solid droplets, following recalescence, under certain conditions. This manifests as a measured temperature depression due to the Gibbs-Thomson effect, with a magnitude of to in simulations. The temperature rises to that of the stable outer mantle as freezing progresses and the droplets re-melt. It is demonstrated that the effect occurs below a critical mantle thickness. A physical explanation for the origin of the effect is offered showing that it is consistent with solid-state de-wetting phenomena. Consideration is also given to the limitations of the current model configuration.

Large, M. J.; Pearce, J. V.

2014-07-01

177

Freezing and thawing or freezing, thawing, and aging effects on beef tenderness.  

PubMed

The objective of this study was to determine the effect of freezing and thawing or freezing and thawing with an additional aging period after frozen storage on the tenderness of longissimus lumborum (LL) and semitendinosus (ST) steaks relative to aged, fresh steaks. Left-side LL and ST (n = 35 each) were obtained from U.S. Select carcasses classified at the grading stand by the U.S. Meat Animal Research Center visible and near-infrared spectroscopy tenderness system to have predicted slice shear force greater than 16.5 kg at 14 d postmortem. At 2 d postmortem, 2.54 cm thick steaks were cut from each muscle and assigned to 1 of the following treatments: 2 d fresh (2FRESH), 2 d freeze + thaw (2FREEZE), 2 d freeze + thaw + 12 d age (2FREEZE+12AGE), 14 d fresh (14FRESH), 14 d freeze + thaw (14FREEZE), 14 d freeze + thaw + 14 d age (14FREEZE+14AGE), and 28 d fresh (28FRESH). Steaks assigned to a freezing treatment were frozen at -26°C for 30 d before thawing/cooking or thawing with an additional aging period at 2°C. Slice shear force for LL and ST was lower (P < 0.01) for 2FREEZE (27.4 and 24.5 kg) and 14FREEZE (22.4 and 22.4 kg) compared to 2FRESH (33.0 and 29.2 kg) and 14FRESH (25.3 and 25.5 kg), respectively. Slice shear force for LL and ST was lower (P < 0.01) for 2FREEZE+12AGE (17.8 and 20.8 kg) and 14FREEZE+14AGE (14.6 and 19.0 kg) compared to 14FRESH (25.3 and 25.5 kg) and 28FRESH (18.7 and 21.7 kg), respectively. Desmin degradation for LL was not different (P > 0.05) between 2FREEZE (21.0%) and 2FRESH (14.6%) or between 14FREEZE (40.4%) and 14FRESH (38.4%); however, desmin degradation was higher (P < 0.06) in 2FREEZE+12AGE (46.7%) and 14FREEZE+14AGE (71.1%) when compared to 14FRESH (38.4%) and 28FRESH (60.5%), respectively. Cooking loss for LL was higher (P < 0.01) in 2FREEZE+12AGE (15.2%) compared to 14FRESH (14.0%) but was not different (P > 0.05) between 14FREEZE+14AGE (15.0%) and 28FRESH (14.3%). Freezing and thawing or a combination of freezing, thawing, and aging resulted in increased tenderness for LL and ST steaks when compared to fresh steaks with the same aging time. These results indicate freezing could be incorporated into normal commercial product distribution processes to improve the consistency of meat tenderness. Researchers who freeze steaks before tenderness assessment should be aware and acknowledge that freezing affects tenderness data. PMID:24671601

Grayson, A L; King, D A; Shackelford, S D; Koohmaraie, M; Wheeler, T L

2014-06-01

178

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

179

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

180

Hot big bang or slow freeze?  

E-print Network

We confront the big bang for the beginning of the universe with an equivalent picture of a slow freeze - a very cold and slowly evolving universe. In the freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The freeze and big bang pictures both describe the same observations or physical reality. We present a simple "crossover model" without a big bang singularity. In the infinite past space-time is flat. Our model is compatible with present observations, describing the generation of primordial density fluctuations during inflation as well as the present transition to a dark energy dominated universe.

C. Wetterich

2014-01-21

181

Hot big bang or slow freeze?  

NASA Astrophysics Data System (ADS)

We confront the big bang for the beginning of the universe with an equivalent picture of a slow freeze - a very cold and slowly evolving universe. In the freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The freeze and big bang pictures both describe the same observations or physical reality. We present a simple “crossover model” without a big bang singularity. In the infinite past space-time is flat. Our model is compatible with present observations, describing the generation of primordial density fluctuations during inflation as well as the present transition to a dark energy-dominated universe.

Wetterich, C.

2014-09-01

182

Freezing precipitation in the Southeastern United States  

E-print Network

- ample of freezing precipitation coating trees is shown in Fig, 1~ a photograph taken during a storm in College Station~ Texas~ on 6 November 1959 ' It is most ccmmonly referred to as an ice storm, a glaze storm~ or freezing rain (or freezing drizzle... dollars in damages to trees alone Tnese and other significan't sto ms occurring $n tha - ou heastern Wn1tEK3 Sta'tes ( 1 the past 30 years) are listed in Ta?le 1, The amount of ice forming on e~ose i objects varies frc. . storm to storm. According...

Young, William Robert

2012-06-07

183

Elastic properties and freezing of argon confined in mesoporous glass  

NASA Astrophysics Data System (ADS)

We study the elastic properties of argon confined in mesoporous Vycor glass with a mean pore diameter of 8 nm. For this purpose volumetric adsorption and desorption measurements are combined with simultaneous ultrasonic measurements. Therewith we obtain the effective shear modulus as a function of the pore filling reflecting both the spatial arrangement and the freezing process of confined argon. Below the freezing point of argon the adsorption process proceeds in three steps. (I) The first adsorbed layers of argon do not contribute to the measured shear modulus, i.e., they do not behave like a solid. (II) In an intermediate range of pore filling the shear modulus increases linearly with increasing amount of adsorbate, i.e., the process of freezing starts, probably with the formation of capillary sublimate. (III) At a certain filling fraction an abrupt rise of the shear modulus up to a plateau value is observed. This step indicates either a change in the spatial distribution of the capillary condensate or a change in its intrinsic properties. The lower the temperature, the smaller the characteristic filling fractions at which these transitions occur. During desorption a hysteresis of the shear modulus, of the attenuation, and hence of the state of the adsorbate is observed.

Schappert, Klaus; Pelster, Rolf

2008-11-01

184

Depression in Older Adults  

MedlinePLUS

... You are here Home » Depression In Older Adults Depression In Older Adults Depression affects more than 19 ... combination of both. [8] Older Adult Attitudes Toward Depression: According to a Mental Health America survey [9] ...

185

Understanding Depression (For Parents)  

MedlinePLUS

... changes in mood from depression to mania. Continue Causes of Depression Depression usually isn't caused by one event ... on with their kids, but parents don't cause depression. However, it is true that parental separation, illness, ...

186

Freeze concentration beats the heat  

SciTech Connect

This paper reports on freeze concentration (FC) which saves energy and money in packaging, shipping, and storing food products. FC---in contrast to existing heat-evaporation processes---retains volatile flavor and aroma compounds in food products so that no additives are required to restore the taste and smell of the original product. In recent tests on orange, grapefruit, and pineapple juices, reconstituted FC juices were found to be superior in taste to juices produced by evaporation and similar to the original pasteurized juices. The dairy industry, which is the largest user of energy for concentration in the food sector, is looking to FC for new products such as frozen concentrated milk as well as better use of the milk by-products of cheese production. The biggest potential for new FC applications is in those industries that consume large amounts of energy for separation processing, according to a 1987 report prepared for EPRI. In the food industry, this includes milk, vinegar, and beer producers. Potential applications also abound in the pulp and paper, pharmaceutical, chemical, and petroleum industries. FC separates substances via crystallization at substantial energy savings.

Rosen, J.

1990-12-01

187

Sublimation of Formaldehyde in Freeze-Drying.  

National Technical Information Service (NTIS)

Formaldehyde solution, commonly used to inactivate bacterial, rickettsial and viral suspensions during the preparation of vaccine, is known to have a deleterious effect on many antigens during freeze-drying. Sublimation of formaldehyde in shell-frozen and...

P. L. Altieri, S. Berman, J. P. Lowenthal

1977-01-01

188

Freeze Crystallization Processes: Efficiency by Flexibility  

E-print Network

Energy consumption in fractionating solutions by distillation and evaporation can be reduced by 70% to 90% by using freeze crystallization processes. The thermodynamic bases for the substantially lower energy requirements include: 1) The phase...

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

1983-01-01

189

Freezing Time Estimation for a Cylindrical Food Using an Inverse Method  

NASA Astrophysics Data System (ADS)

Most of the published methods for estimating the freezing time require thermal properties of the product and any relevant heat transfer coefficients between the product and the cooling medium. However, the difficulty of obtaining thermal data for use in industrial freezing system of food has been pointed out. We have developed a new procedure for estimating the time to freeze a food of a slab by using the inverse method, which does not require the knowledge of thermal properties of the food being frozen. The method of applying inverse method to estimation of freezing time depends on the shape of the body to be frozen. In this paper, we explored the method of applying inverse method to the food body of cylindrical shape, using selected explicit expressions to describe the temperature profile. The temperature profile was found to be successfully approximated by a logarithmic function, with which an approximate equation to describe the freezing time was derived. An inversion procedure of estimating freezing time associated with the approximate equation, was validated via a numerical experiment.

Hu, Yao Xing; Mihori, Tomoo; Watanabe, Hisahiko

190

Freezing of gait in Chinese patients with Parkinson Disease.  

PubMed

A total of 474 Chinese Parkinson disease (PD) patients were evaluated to explore the prevalence and clinical correlates of freezing of gait (FOG) in this cross-sectional study. Two hundred and twenty-one PD patients (46.62%) reported FOG (freezers). FOG occurred more frequently in older patients and patients with low limbs as the site of onset, longer disease duration and higher Hoehn and Yahr (H&Y) stage (P<0.05). After adjusting for confounding factors, the freezers had higher scores for the Unified PD Rating Scale (UPDRS) part III, Non-Motor Symptoms Scale (NMSS), PD Questionnaire 39 (PDQ-39), Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA), and lower scores for the Mini-Mental status examination (MMSE), frontal assessment battery (FAB) and Montreal Cognitive Assessment (MoCA) compared with the non-freezers (P<0.05). The binary logistic regression analysis indicated that festination, falls, a high daily dose of levodopa, the use of a dopamine receptor agonist, a high H&Y stage, the severity of urinary symptoms and a high HAMD score were associated with FOG. FOG is a relatively common disabling symptom in Chinese PD patients. Patients that were older, or reported a longer disease duration, low limbs as the site of onset and a more severe disability were more likely to experience FOG. Non-motor symptoms, especially urinary symptoms and depression, may also be related to FOG. PMID:25043665

Ou, Ruwei; Guo, Xiaoyan; Song, Wei; Cao, Bei; Yang, Jing; Wei, Qianqian; Shao, Na; Shang, Huifang

2014-10-15

191

On Freezing and Reactivating Learnt Clauses  

Microsoft Academic Search

\\u000a In this paper, we propose a new dynamic management policy of the learnt clause database in modern sat solvers. It is based on a dynamic freezing and activation principle of the learnt clauses. At a given search state, using\\u000a a relevant selection function, it activates the most promising learnt clauses while freezing irrelevant ones. In this way,\\u000a clauses learned at

Gilles Audemard; Jean-Marie Lagniez; Bertrand Mazure; Lakhdar Saïs

192

Freezing of Xylem Sap Without Cavitation  

PubMed Central

Freezing of stem sections and entire twigs of hemlock (Tsuga canadensis) has been demonstrated to occur without increasing the resistance to the movement of water through the frozen part after rewarming. This was interpreted to mean that freezing did not produce cavitation in the xylem sap even though A) the sap was unquestionably frozen; B) it contained dissolved gases; and C) it was under tension before freezing and after. Freezing stem sections of some other evergreen gymnosperms during the summer again produced no evidence for cavitation of the xylem sap. On the other hand, freezing stem sections of some angiosperms invariably increased the resistance to sap flow leading to wilting and death in a few hours when the sap tension was at normal daytime values at the time of freezing. These results were interpreted to mean that the bordered pits on the tracheids of gymnosperms function to isolate the freezing sap in each tracheid so that the expansion of water upon freezing not only eliminates any existing tension but also develops positive pressure in the sap. Dissolved gases frozen out of solution may then be redissolved under this positive pressure as melting occurs. As the bubbles are reduced in size by this ice pressure developed in an isolated tracheid, further pressure is applied by the surface tension of the water against air. If the bubbles are redissolved or are reduced to sufficient small size by the time the tension returns to the sap as the last ice crystals melt, then the internal pressure from surface tension in any existing small bubbles may exceed the hydrostatic tension of the melted sap and the bubbles cannot expand and will continue to dissolve. PMID:16656485

Hammel, H. T.

1967-01-01

193

Compression of cooked freeze-dried carrots  

E-print Network

. Reduction in volume of up to 18-fold can be obtained by com- pressing dehydrated vegetables (Rabman, 1969). During World War II, the United Kingdom produced dehydrated cabbage and carrots in compressed blocks (Gooding and Rolfe, 1967). Fairbrother (1968...-propanol at low concentration by freeze-drying carbohydrate solutions. J. of Food Sci. 37:617. Flosdorf, E. W. 1949. "Freeze-drying, " Reinhold Publishing Co. , New York. Gooding, E. B. B. and Rolfe, E. J. 1957. Some Recent Work on Dehy- dration...

Macphearson, Bruce Alan

2012-06-07

194

Nonpsychotic Postpartum Depression Among Adolescent Mothers  

Microsoft Academic Search

This study examined the extent to which childbearing increases vulnerability to clinical depression and depressive symptomatology among primiparous adolescent girls (ages 14 to 18). Childbearing Ss (n = 128) were assessed during pregnancy, 6 weeks postpartum, and 1 year postpartum. Matched nonchildbearing Ss (n = 114) were assessed at corresponding time points. Six weeks postpartum, 6% of the childbearing adolescents

Beth R. Troutman; Carolyn E. Cutrona

1990-01-01

195

Depressed Mood in Adolescence: Who Goes Unnoticed?  

ERIC Educational Resources Information Center

Depression in adolescence typically has a debilitating toll in terms of academic and social functioning, and it predicts a variety of negative outcomes later. Previous research points out that once on a depressed trajectory in development, an individual becomes more likely to stay on this course because of the tendency to both alienate and…

Watson, Cary M.; Quatman, Teri; Swanson, Connie

196

Moments of the particle phase-space density at freeze-out and coincidence probabilities  

E-print Network

It is pointed out that the moments of phase-space particle density at freeze-out can be determined from the coincidence probabilities of the events observed in multiparticle production. A method to measure the coincidence probabilities is described and its validity examined.

A. Bialas; W Czyz; K. Zalewski

2005-08-29

197

Enhanced uptake of atmospheric CO2 during freezing of seawater: A field study in Storfjorden, Svalbard  

Microsoft Academic Search

The waters of Storfjorden, a fjord in southern Svalbard, were investigated in late April 2002. The temperature was at the freezing point throughout the water column; the salinity in the top 30 m was just above 34.8, then increased nearly linearly to about 35.8 at the bottom. Nutrient and oxygen concentrations showed a minimal trend all through the water column,

Leif G. Anderson; Eva Falck; E. Peter Jones; Sara Jutterström; Jim H. Swift

2004-01-01

198

Shyness Predicts Depressive Symptoms among Adolescents : A Prospective Study  

ERIC Educational Resources Information Center

This study examines the relation between shyness, social support and depressive symptoms in a sample of 259 students (aged 14-16 years) in two secondary schools. Results at both time-points showed positive associations of depressive symptoms with shyness and with being female and negative associations of depressive symptoms with social support and…

Murberg, Terje A.

2009-01-01

199

Altered BDNF and Dopamine Levels In Depression  

NSDL National Science Digital Library

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

2009-12-26

200

Natural freezing as a wastewater treatment method: E. coli inactivation capacity  

Microsoft Academic Search

Inactivation capacity of E. coli (strain ATCC 15597) in water by natural freezing was examined via two freezing methods: spray freezing and freezing in a freezer. The effect of freezing temperature (?5, ?15 and ?35°C), storage time, freeze–thaw cycles on the survival of the test organism were investigated. In addition, the number of cells injured by the freezing process was

W. Gao; D. W. Smith; Y. Li

2006-01-01

201

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.

202

Nutritional Interventions in Depression and Perinatal Depression  

PubMed Central

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

2013-01-01

203

UltraViolet Freeze-in  

E-print Network

If dark matter is thermally decoupled from the visible sector, the observed relic density can potentially be obtained via freeze-in production of dark matter. Typically in such models it is assumed that the dark matter is connected to the thermal bath through feeble renormalisable interactions. Here, rather, we consider the case in which the hidden and visible sectors are coupled only via non-renormalisable operators. This is arguably a more generic realisation of the dark matter freeze-in scenario, as it does not require the introduction of diminutive renormalisable couplings. We examine general aspects of freeze-in via non-renormalisable operators in a number of toy models and present several motivated implementations in the context of Beyond the Standard Model physics. Specifically, we study models related to the Peccei-Quinn mechanism and Z' portals.

Elahi, Fatemeh; Unwin, James

2014-01-01

204

Determination of ethanol in whey-sugar solutions by freezing. [Kluyveromyces fragilis and Saccharomyces cerevisiae  

SciTech Connect

The composition of solutions undergoing yeast fermentation was stimulated by using direct-acid-set cottage cheese whey containing increasing amounts of EtOH (0 to 5.4%) with decreasing amounts of sucrose (10 to 0%). Each decrease of 0.54 g EtOH decreased specific gravity by 0.0046 unit and lowered the freezing point by 0.159 H (the Hortvet unit). Whey containing 10% added sucrose was treated as follows: (a) inoculated with Kluyveromyces fragilis, (b) carbohydrate splitting enzymes added and inoculated with Kluyveromyces fragilis and (c) carbohydrate splitting enzymes added and inoculated with Saccharomyces cerevisiae. All mixtures were incubated 48 h at 32 degrees during which 6 samples from each treatment were analyzed for total solids, specific gravity and freezing point. No difference was noted between samples treated with enzymes or those treated with the 2 yeasts cultured as related to decrease in total solids concentration or specific gravity. Each 0.001 H decrease in freezing point was accompanied by a total solids decrease of 0.006 g/100 g whey in the nonenzyme treated sample, and 0.008 g and 0.010 g/100 g whey in the enzyme-treated samples inoculated with Kluyveromyces fragilis and Saccharomyces cerevisiae, respectively. Each 0.001 H change in freezing point was equivalent to a change of 0.00003 specific gravity unit in the nonenzyme-treated sample and 0.000043 and 0.000048 specific gravity unit in the enzyme-treated samples inoculated with Kluyveromyces fragilis and Saccharomyces cerevisiae, respectively. The precision with which freezing point can be determined suggests its use in evaluating the amount of EtOH produced during fermentation.

Demott, B.J.

1982-01-01

205

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

PubMed

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

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

2013-07-15

206

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

PubMed

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

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

2006-09-01

207

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 ...

208

Depression and Suicide Risk  

MedlinePLUS

... as if life isn’t worth living. i Depression and Suicide Risk (2014) Prevalence: Ranges of lifetime ... disorder due to another medical disorder Relationship Between Depression & Suicide: Depression is the psychiatric diagnosis most 1. ...

209

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

210

Depression and Parkinson's Disease  

MedlinePLUS

... see the NIMH booklet on Depression . What is Parkinson's disease? Parkinson's disease is a chronic disorder that ... or prevent Parkinson's disease. How are depression and Parkinson's disease linked? For people with depression and Parkinson's ...

211

Breast Cancer and Depression  

MedlinePLUS Videos and Cool Tools

... the lower right-hand corner of the player. Breast Cancer and Depression HealthDay October 28, 2014 Related MedlinePlus Pages Breast Cancer Depression Women's Health Transcript Depression is a disabling ...

212

Optimization of the secondary drying step in freeze drying using TDLAS technology.  

PubMed

The secondary drying phase in freeze drying is mostly developed on a trial-and-error basis due to the lack of appropriate noninvasive process analyzers. This study describes for the first time the application of Tunable Diode Laser Absorption Spectroscopy, a spectroscopic and noninvasive sensor for monitoring secondary drying in laboratory-scale freeze drying with the overall purpose of targeting intermediate moisture contents in the product. Bovine serum albumin/sucrose mixtures were used as a model system to imitate high concentrated antibody formulations. First, the rate of water desorption during secondary drying at constant product temperatures (-22 °C, -10 °C, and 0 °C) was investigated for three different shelf temperatures. Residual moisture contents of sampled vials were determined by Karl Fischer titration. An equilibration step was implemented to ensure homogeneous distribution of moisture (within 1%) in all vials. The residual moisture revealed a linear relationship to the water desorption rate for different temperatures, allowing the evaluation of an anchor point from noninvasive flow rate measurements without removal of samples from the freeze dryer. The accuracy of mass flow integration from this anchor point was found to be about 0.5%. In a second step, the concept was successfully tested in a confirmation experiment. Here, good agreement was found for the initial moisture content (anchor point) and the subsequent monitoring and targeting of intermediate moisture contents. The present approach for monitoring secondary drying indicated great potential to find wider application in sterile operations on production scale in pharmaceutical freeze drying. PMID:21359604

Schneid, Stefan C; Gieseler, Henning; Kessler, William J; Luthra, Suman A; Pikal, Michael J

2011-03-01

213

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

214

[Depressive symptoms and sexuality].  

PubMed

The mutually reinforcing dyad of depressive symptoms and erectile dysfunction is scientifically established. The cure of depression improves sexual dysfunction (SD) and the treatment of SD induces improvement of depression. Most of anti-depressants induce negative sexual side effects that lead to non-compliance of these treatments. The knowledge of interrelation between depression, anti-depressants and sexuality is of great importance in clinical practice. PMID:25148948

Porto, Robert

2014-10-01

215

Depression in adolescence.  

PubMed

Major depression is a common mental health disorder in adolescents that predicts a significant risk for recurrence in adulthood. Suicide is the third most frequent cause of deaths in this age group, and depression is a significant risk factor for suicidal ideation and attempts. Risks for depression and suicidal ideation are reviewed, and subtypes of depression are discussed. Difficulties associated with identification of depression and suicidal ideation in adolescents and biologic therapies for adolescent depression are reviewed. PMID:11753112

Sampson, S M; Mrazek, D A

2001-12-01

216

Freezing cleans food processing wastewater  

SciTech Connect

Snowfluent is a technology which atomizes wastewater effluent and sprays it into the air as ice crystals at cold temperatures. It has been found effective in treating municipal sewage and food processing wastes. This bulletin reviews pilot- and production-scale studies conducted at an Alberta malt producer to test whether the Snowfluent process has further applications for the treatment of food processing wastes. The study was designed to determine the percentage of nutrients removed by the technology, the point at which contaminants are reduced, the effect of the process on the shallow water table, and the health risk to operators involved.

Not Available

1998-01-01

217

Importance of using complementary process analyzers for the process monitoring, analysis, and understanding of freeze drying.  

PubMed

The aim of the present paper is to demonstrate the importance of using complementary process analyzers (PAT tools) for the process monitoring, analysis, and understanding of freeze drying. A mannitol solution was used as a model system. Raman spectroscopic, near-infrared (NIR) spectroscopic, plasma emission spectroscopic, and wireless temperature measurements (TEMPRIS) were simultaneously performed in-line and real-time during each freeze-drying experiment. The combination of these four process analyzers to monitor a freeze-drying process is unique. The Raman and NIR data were analyzed using principal component analysis (PCA) and multivariate curve resolution (MCR), while the plasma emission spectroscopic and wireless temperature measurement data were analyzed using univariate data analysis. It was shown that the considered process analyzers do not only complement but also mutually confirm each other with respect to process step end points, physical phenomena occurring during freeze drying (process understanding), and product characterization (solid state). Furthermore and most important, the combined use of the process analyzers helped to identify flaws in previous studies in which these process analyzers were studied individually. Process analyzers might wrongly indicate that some process steps are fulfilled. Finally, combining the studied process analyzers also showed that more information per process analyzer can be obtained than previously described. A combination of Raman and plasma emission spectroscopy seems favorable for the monitoring of nearly all critical freeze-drying process aspects. PMID:19681620

De Beer, T R M; Wiggenhorn, M; Veillon, R; Debacq, C; Mayeresse, Y; Moreau, B; Burggraeve, A; Quinten, T; Friess, W; Winter, G; Vervaet, C; Remon, J P; Baeyens, W R G

2009-09-15

218

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. PMID:24219183

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

2014-01-01

219

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

E-print Network

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

Koutstaal, Wilma

220

Doering 6/2004 Freezing Cell Lines  

E-print Network

and thawing are below. Reagents/equipment: Sterile freezer vials 50% glycerol, sterile Dry ice/ethanol bath a few times. 5. Freeze the vials on dry ice or in a dry ice/ethanol bath. 6. Store the vials you plan to thaw. Remove the vial you need from the freezer (ideally to dry ice) and quickly scratch

Doering, Tamara

221

TISSUE FREEZING METHODS FOR CRYOSTAT SECTIONING  

E-print Network

, sucrose cryoprotected tissue freezing ­ Tissue is in OCT and may be frozen using dry ice or the flash - and depending on the method prepare liquid nitrogen, isopentane, dry ice. · Label ahead of time - cryo molds, aluminum foil, specimen bags while at room temperature. · Covered Foam cooler with crushed dry ice

Chisholm, Rex L.

222

Freeze fracturing of elastic porous media  

E-print Network

The physical motivation behind this thesis is the phenomenon of fracturing of rocks and other porous media due to ice growth inside pre-existing faults and large pores. My aim is to explain the basic physical processes taking place inside a freezing...

Vlahou, Ioanna

2012-06-12

223

Theoretical prediction of ‘optimal’ freezing programmes  

Microsoft Academic Search

We have developed a quantitative description of the osmotic behaviour of cells during freezing without a presupposed value of the cooling rate. Instead, at all times the intracellular supercooling is maximised provided that it does not exceed a predetermined value ‘p’ (e.g., 2°C). This should preclude intracellular ice formation, but also ensures that the osmotic gradient and the CPA concentration

H. Woelders; A. Chaveiro

2004-01-01

224

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

225

Freeze-Dehydration by Microwave Energy.  

National Technical Information Service (NTIS)

A general unsteady state analysis is used to derive a mathematical model of the freeze-drying process using microwave heating. The temperature and water vapor concentration profiles inside the material being dried are calculated. The model is applied to s...

P. R. F. Peltre

1974-01-01

226

Effects of freezing on plant mesophyll cells.  

PubMed

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

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

1988-01-01

227

Deliquesence and freezing of stratospheric aerosol observed by balloonborne backscattersondes  

SciTech Connect

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

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

1995-05-15

228

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

229

Tandem High-pressure Freezing and Quick Freeze Substitution of Plant Tissues for Transmission Electron Microscopy.  

PubMed

Since the 1940s transmission electron microscopy (TEM) has been providing biologists with ultra-high resolution images of biological materials. Yet, because of laborious and time-consuming protocols that also demand experience in preparation of artifact-free samples, TEM is not considered a user-friendly technique. Traditional sample preparation for TEM used chemical fixatives to preserve cellular structures. High-pressure freezing is the cryofixation of biological samples under high pressures to produce very fast cooling rates, thereby restricting ice formation, which is detrimental to the integrity of cellular ultrastructure. High-pressure freezing and freeze substitution are currently the methods of choice for producing the highest quality morphology in resin sections for TEM. These methods minimize the artifacts normally associated with conventional processing for TEM of thin sections. After cryofixation the frozen water in the sample is replaced with liquid organic solvent at low temperatures, a process called freeze substitution. Freeze substitution is typically carried out over several days in dedicated, costly equipment. A recent innovation allows the process to be completed in three hours, instead of the usual two days. This is typically followed by several more days of sample preparation that includes infiltration and embedding in epoxy resins before sectioning. Here we present a protocol combining high-pressure freezing and quick freeze substitution that enables plant sample fixation to be accomplished within hours. The protocol can readily be adapted for working with other tissues or organisms. Plant tissues are of special concern because of the presence of aerated spaces and water-filled vacuoles that impede ice-free freezing of water. In addition, the process of chemical fixation is especially long in plants due to cell walls impeding the penetration of the chemicals to deep within the tissues. Plant tissues are therefore particularly challenging, but this protocol is reliable and produces samples of the highest quality. PMID:25350384

Bobik, Krzysztof; Dunlap, John R; Burch-Smith, Tessa M

2014-01-01

230

Foliar applied urea improves freezing protection to avocado and peach  

Microsoft Academic Search

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

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

1996-01-01

231

47 CFR 64.1190 - Preferred carrier freezes.  

Code of Federal Regulations, 2012 CFR

...of the specific procedures necessary to lift a preferred carrier freeze; an explanation...change in carrier selection unless he or she lifts the freeze. (iii) An explanation of...change in carrier selection unless she or he lifts the preferred carrier freeze; and...

2012-10-01

232

Depression's forgotten genealogy: notes towards a history of depression.  

PubMed

The history of depression remains unwritten, yet historians harbor plentiful assumptions about its pre-1800 past. These views are necessarily colored, even shaped, by modern views of depression formed after its nineteenth-century medicalization. A history of depression from ancient to modern times is an impossible task to complete successfully and would require, as a minimum, the historian's utmost vigilance to nuance, difference, and the inclusion of non-medical literature, especially poetry, drama and non-didactic prose. Nevertheless, five points about depression's pre-1800 European profile can confidently be made: (1) it developed along lines of female rather than male gender; (2) was transformed in the long eighteenth century when it blended with male madness under the sway of the cults of a pan-European sensibility movement; (3) always embedded a problematic pseudo-depressive state, or feigned version, which acted to permit female escape from dire socio-economic situation; (4) included sustained chronic duration as a requirement in its theory from the Renaissance forward; (5) is richly documented in its pre-1800 versions in imaginative literature, its often overlooked genealogy. PMID:11624608

Rousseau, G

2000-03-01

233

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. PMID:24141845

Wang, Yuan-Pang; Gorenstein, Clarice

2013-01-01

234

The WAG/Rij strain: a genetic animal model of absence epilepsy with comorbidity of depression [corrected].  

PubMed

A great number of clinical observations show a relationship between epilepsy and depression. Idiopathic generalized epilepsy, including absence epilepsy, has a genetic basis. The review provides evidence that WAG/Rij rats can be regarded as a valid genetic animal model of absence epilepsy with comorbidity of depression. WAG/Rij rats, originally developed as an animal model of human absence epilepsy, share many EEG and behavioral characteristics resembling absence epilepsy in humans, including the similarity of action of various antiepileptic drugs. Behavioral studies indicate that WAG/Rij rats exhibit depression-like symptoms: decreased investigative activity in the open field test, increased immobility in the forced swimming test, and decreased sucrose consumption and preference (anhedonia). In addition, WAG/Rij rats adopt passive strategies in stressful situations, express some cognitive disturbances (reduced long-term memory), helplessness, and submissiveness, inability to make choice and overcome obstacles, which are typical for depressed patients. Elevated anxiety is not a characteristic (specific) feature of WAG/Rij rats; it is a characteristic for only a sub-strain of WAG/Rij rats susceptible to audiogenic seizures. Interestingly, WAG/Rij rats display a hyper-response to amphetamine similar to anhedonic depressed patients. WAG/Rij rats are sensitive only to chronic, but not acute, antidepressant treatments, suggesting that WAG/Rij rats fulfill a criterion of predictive validity for a putative animal model of depression. However, more and different antidepressant drugs still await evaluation. Depression-like behavioral symptoms in WAG/Rij rats are evident at baseline conditions, not exclusively after stress. Experiments with foot-shock stress do not point towards higher stress sensitivity at both behavioral and hormonal levels. However, freezing behavior (coping deficits) and blunted response of 5HT in the frontal cortex to uncontrollable sound stress, increased c-fos expression in the terminal regions of the meso-cortico-limbic brain systems and greater DA response of the mesolimbic system to forced swim stress suggest that WAG/Rij rats are vulnerable to some, but not to all types of stressors. We propose that genetic absence epileptic WAG/Rij rats have behavioral depression-like symptoms, are vulnerable to stress and might represent a model of chronic low-grade depression (dysthymia). Both 5HT and DAergic abnormalities detected in the brain of WAG/Rij rats are involved in modulation of vulnerability to stress and provocation of behavioral depression-like symptoms. The same neurotransmitter systems modulate SWDs as well. Recent studies suggest that the occurrence and repetition of absence seizures are a precipitant of depression-like behavior. Whether the neurochemical changes are primary to depression-like behavioral alterations remains to be determined. In conclusion, the WAG/Rij rats can be considered as a genetic animal model for absence epilepsy with comorbidity of dysthymia. This model can be used to investigate etiology, pathogenic mechanisms and treatment of a psychiatric comorbidity, such as depression in absence epilepsy, to reveal putative genes contributing to comorbid depressive disorder, and to screen novel psychotropic drugs with a selective and/or complex (dual) action on both pathologies. PMID:21093520

Sarkisova, Karine; van Luijtelaar, Gilles

2011-06-01

235

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

236

Depression and Headaches  

MedlinePLUS

Home » Depression and Headache Depression and Headache Submitted by Admin on Thu, 2007-10-25 17:37 It is well known that the patient having ... in patients with depressive reactions. The presence of depression is often subtle and the diagnosis is often ...

237

Depressive personality disorder  

Microsoft Academic Search

This article reviews the theoretical construct of depressive personality disorder and its related research. The history of depressive personality disorder is reviewed. It is concluded that differing theories converge on similar descriptions and mechanisms of development for the depressive personality disorder. Substantial empirical work supports the diagnostic distinctiveness of depressive personality disorder in clinical populations. Past and current assessment devices

Steven K. Huprich

1998-01-01

238

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

239

Seasonal freeze resistance of rainbow smelt (Osmerus mordax) is generated by differential expression of glycerol-3-phosphate dehydrogenase, phosphoenolpyruvate carboxykinase, and antifreeze protein genes.  

PubMed

In winter, rainbow smelt (Osmerus mordax) accumulate glycerol and produce an antifreeze protein (AFP), which both contribute to freeze resistance. The role of differential gene expression in the seasonal pattern of these adaptations was investigated. First, cDNAs encoding smelt and Atlantic salmon (Salmo salar) phosphoenolpyruvate carboxykinase (PEPCK) and smelt glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were cloned so that all sequences required for expression analysis would be available. Using quantitative PCR, expression of beta actin in rainbow smelt liver was compared with that of GAPDH in order to determine its validity as a reference gene. Then, levels of glycerol-3-phosphate dehydrogenase (GPDH), PEPCK, and AFP relative to beta actin were measured in smelt liver over a fall-winter-spring interval. Levels of GPDH mRNA increased in the fall just before plasma glycerol accumulation, implying a driving role in glycerol synthesis. GPDH mRNA levels then declined during winter, well in advance of serum glycerol, suggesting the possibility of GPDH enzyme or glycerol conservation in smelt during the winter months. PEPCK mRNA levels rose in parallel with serum glycerol in the fall, consistent with an increasing requirement for amino acids as metabolic precursors, remained elevated for much of the winter, and then declined in advance of the decline in plasma glycerol. AFP mRNA was elevated at the onset of fall sampling in October and remained elevated until April, implying separate regulation from GPDH and PEPCK. Thus, winter freezing point depression in smelt appears to result from a seasonal cycle of GPDH gene expression, with an ensuing increase in the expression of PEPCK, and a similar but independent cycle of AFP gene expression. PMID:16555199

Liebscher, Ryan S; Richards, Robert C; Lewis, Johanne M; Short, Connie E; Muise, Denise M; Driedzic, William R; Ewart, K Vanya

2006-01-01

240

[Causes of depression].  

PubMed

This paper describes four nosological categories of depressive disorder according to the fundamental or prime cause: endogen depression, situative depression, psychogen depression and somatogen (also pharmacogen or addictive) depression. Recent advances in neurobiology provide the commun pathogenic mechanism distribuited in neurochemical, neuroendocrine and neuroinmune factors, with at the end a cellular and molecular sequence beyond the synapse. There is an increased risk of depression multiplied by three or four in the elderly, obese, unemployed and inmigrant and it is very frequent in terminally ill patients with a pervasive desire for death. Finally, eight personalized preventive guidelines enable to decrease the individual risk of depression in more than a fifty per cent. PMID:23350306

Fernández, Francisco Alonso

2011-01-01

241

Impurity and thermal modelling of SPRT fixed-points  

NASA Astrophysics Data System (ADS)

Impurities in pure metal fixed points for the calibration of standard platinum resistance thermometers (SPRTs) causes significant variations in the freezing temperature, of the order of sub-mK to several mK. This often represents the largest contribution to the overall uncertainty of the fixed point temperature, and it is therefore of great interest to explore ways of correcting for this effect. The sum of individual estimates (SIE) method, in which the contributions of all the impurities are summed, is the recommended way of determining the correction if one has an accurate knowledge of the impurities present and their low concentration liquidus slopes. However, due to the difficulty in obtaining reliable iningot impurity corrections, it remains useful to investigate the influence of impurities on freezing curves using modeling techniques, and ultimately to parameterize the freezing curve by e.g. least-squares fitting to make corrections to the temperature of the freeze. Some success in analyzing freezing curves has been achieved. When parameterizing experimentally determined freezing curves, it is necessary to reliably determine the freezing end-point, and minimize spurious thermal effects. We outline some methods for meeting these requirements. As the influence of impurities is always convolved with thermal influences it is instructive to construct a model which takes into account both heat and impurity transport. We describe the development of more sophisticated models which take both these effects into account.

Pearce, J. V.; Veltcheva, R. I.; Large, M. J.

2013-09-01

242

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

243

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

244

Can stress cause depression?  

PubMed

The central issue raised in this paper is: can stress cause depression? Phrased more precisely: can stress cause brain disturbances thought to underlie (certain forms of) depression or particular components of the depressive syndrome. Focussing on 5-HT and the stress hormones, this question was answered in the affirmative, based on the following two considerations: (1) changes in the 5-HT and stress hormone systems produced by sustained stress, mimic to a substantial extent the disturbances in these systems that may be observed in depression; (2) substantial evidence indicates that the 5-HT and stress hormone disturbances in depression are of pathophysiological significance and not merely a consequence of the depressed state or a product of stress generated by the depressed state. Furthermore, the question was raised whether a depression type could be identified particularly stress-inducible. This question, too, was answered in the affirmative. The depression type in question was named anxiety/aggression-driven depression and characterized on three levels: psychopathologically, biologically and psychologically. Preferential treatment of this depression type was discussed. In studying stress-inducible depression biological depression research should shift focus from depression per se to the neurobiological sequelae of stress. Treatment of stress-inducible depressions and particularly its prevention should be geared towards reduction of stress and stress sensitiveness, utilising both biological and psychological means. PMID:16166019

van Praag, Herman M

2005-01-01

245

Freeze Thaw Durability of Modern Concrete Mixtures  

E-print Network

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

246

Freeze-branding to permanently mark bats  

Microsoft Academic Search

We tested the effectiveness of freeze-branding as a permanent marking technique on 4 species of bats: Brazilian free-tailed bat (Tadarida brasiliensis), Townsend's big-eared bat (Corynorhinus townsendil), big brown bat (Eptesicus fuscus), and western small-footed myotis (Myotis ciliolabrum). Small copper branding irons (9.3 g and 15.6 g) were cooled in a mixture of dry ice and ethyl alcohol and applied to

Richard E. Sherwin; Shauna Haymond; Rebeccah Olsen

247

One-stage model of foods freezing  

Microsoft Academic Search

The freezing process in a NaCl eutectic solution is discussed taking into account both a non-constant specific heat and a non-constant thermal conductivity as potential functions of temperature. The non-linearity of the problem is introduced in the heat diffusion equation and in its boundary conditions. A strictly exact solution is used to solve it. By considering only conduction heat transfer

P. D. Sanz; M. Ramos; J. Aguirre-Puente

1999-01-01

248

Freezing and Frozen-Food Storage  

Microsoft Academic Search

\\u000a Food freezing is the preservation process that depends on the reduction of product temperature to levels well below the temperature\\u000a at which ice crystals begin to form within the food. By reducing the temperature of the product to -10 to -20°C, the normal\\u000a reactions that cause deterioration of foods are reduced to negligible or minimal rates. These temperature levels limit

Dennis R. Heldman; Richard W. Hartel

249

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

250

Cognitive function in unipolar major depression: A comparison of currently depressed, previously depressed, and never depressed individuals  

Microsoft Academic Search

There is a lack of consensus upon a conclusive cognitive profile characterizing unipolar major depression. Currently depressed (n?=?37), recovered previously depressed (n?=?81), and never depressed controls (n?=?50) underwent assessment of executive functions, working memory, attention, and psychomotor speed. Currently depressed yielded significantly lower test scores than previously and never depressed subjects on a measure of working memory. Both currently depressed

Marianne Halvorsen; Ragnhild Sørensen Høifødt; Ingvild Nordnes Myrbakk; Catharina Elisabeth Arfwedson Wang; Kjetil Sundet; Martin Eisemann; Knut Waterloo

2012-01-01

251

Steam consumption reduction by eutectic freeze crystallization  

SciTech Connect

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 factory energy use. Further reduction is limited by the juice heating needs in the purification operations. Steam for juice heating is 20 to 30% on beets, or 400 to 600 pounds of steam per ton. In efficient factories this is about the steam flow to the evaporators when the pan crystallizers are replaced by freeze crystallization. An approach is described here for a rapid evaluation of effects on the steam balance of basic process changes. It provides a visual guide to restructuring the steam balance that simplifies optimization when such changes are made. The graphic approach is useful in illustrating methods of reducing energy use in a sugar factory, in addition to the current analysis of integration of the hydrate freeze process. For example, membrane and vapor recompression evaporators for juice concentration must be accompanied by major factory modifications to produce any net savings of steam. The reason is the needs for specific steam quantity and quality for the pan evaporators and juice heaters, supplied through the current evaporator trains. Reduction of the steam rate below 25 to 35% on beets will require changes to the conventional juice purification process.

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

1985-01-01

252

Infrared Freezing of Euclidean QCD observables  

E-print Network

We consider the leading one-chain term in a skeleton expansion for QCD observables and show that for energies Q^2>\\Lambda^2, where Q^2=\\Lambda^2 is the Landau pole in the coupling, the skeleton expansion result is equivalent to the standard Borel integral representation, with ambiguities related to infrared (IR) renormalons. For Q^2skeleton expansion result is equivalent to a previously proposed modified Borel representation where the ambiguities are connected with ultraviolet (UV) renormalons. We investigate the Q^2-dependence of the perturbative corrections to the Adler D function, the GLS sum rule, and the polarized and unpolarized Bjorken sum rules. In all these cases the one-chain result changes sign in the vicinity of Q^2=\\Lambda^2, and then exhibits freezing behaviour, vanishing at Q^2=0. Finiteness at Q^2=\\Lambda^2 implies specific relations between the residues of IR and UV renormalons in the Borel plane. These relations, only one of which has previously been noted (though it remained unexplained) are shown to follow from the continuity of the characteristic function in the skeleton expansion. By considering the compensation of non-perturbative and perturbative ambiguities we are led to a result for the Q^2 dependence of these observables at all Q^2, in which there is a single undetermined non-perturbative parameter, and which involves the skeleton expansion characteristic function. The observables freeze to zero in the infrared. We briefly consider the freezing behaviour of the Minkowskian R_{e+e-} ratio.

Paul M. Brooks; C. J. Maxwell

2006-04-28

253

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

PubMed

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

Carson, Johnny L

2014-01-01

254

Intracellular freezing, viability, and composition of fat body cells from freeze-intolerant larvae of Sarcophaga crassipalpis.  

PubMed

Although it is often assumed that survival of freezing requires that ice formation must be restricted to extracellular compartments, fat body cells from freeze-tolerant larvae of the gall fly, Eurosta solidaginis (Diptera, Tephritidae) survive intracellular freezing. Furthermore, these cells are highly susceptible to inoculative freezing by external ice, undergo extensive lipid coalescence upon thawing, and survive freezing better when glycerol is added to the suspension medium. To determine whether these traits are required for intracellular freeze tolerance or whether they are incidental and possessed by fat body cells in general, we investigated the capacity of fat body cells from nondiapause-destined and diapause-destined (i.e., cold-hardy) larvae of the freeze-intolerant flesh fly Sarcophaga crassipalpis (Diptera, Sarcophagidae) to survive intracellular freezing. Fat body cells from both types of larvae were highly susceptible to inoculative freezing; all cells froze between -3.7 to -6.2 degrees C. The highest rates for survival of intracellular freezing occurred at -5 degrees C. The addition of glycerol to the media markedly increased survival rates. Upon thawing, the fat body cells showed little or no lipid coalescence. Fat body cells from E. solidaginis had a water content of only 35% compared to cells from S. crassipalpis larvae that had 52-55%; cells with less water may be less likely to be damaged by mechanical forces during intracellular freezing. PMID:11746564

Davis, D J; Lee, R E

2001-12-01

255

Sponsored by the Belgian Federal Science Policy Office (BELSPO)  

E-print Network

and freezing point rises freezing on: underplating and conduit blockage overdeepening: freezing point depressed ice cap Matanuska Glacier The miracle cure! #12;5 Controversial claims and assertions Background

Knight, Peter G.

256

Personality disorders in bipolar and depressive disorders  

Microsoft Academic Search

The association of mood disorders with personality disorders (PDs) is relevant from a clinical, therapeutic and prognostic point of view. To examine this issue, we compared the prevalence of DSM-III-R personality disorders assessed with SCID-II in patients with depressive (n=117) and bipolar (n=71) disorders both recovered from a major depressive index episode that needed hospital admission. PDs prevalence and comorbidity

Alessandro Rossi; Maria Grazia Marinangeli; Giancarlo Butti; Antonella Scinto; Loredana Di Cicco; Artemis Kalyvoka; Concetta Petruzzi

2001-01-01

257

Disruption of spine homeostasis causes depression.  

PubMed

Depression is one of the most burdensome diseases in the world. Although the exact pathogenesis remains unknown, stress is a well-known risk factor for the development of depression. Recently, stress has been known to induce loss of dendritic spines in neurons. Interestingly, also in human brains, higher levels of anxiety and depression scores are associated with decreased densities of spines in the hippocampus, supporting that the disturbance of spine homeostasis is deeply involved in the pathogenesis of depression. On the other hand, general serotonin vulnerability has been also proposed as a major risk factor in depression, where the paucity of available serotonin is involved in the pathogenesis of depression, indicating that the serotonergic system somehow possesses the ability to regulate spine homeostasis. However, the relationship between spine homeostasis and the serotonergic system is largely unknown. Thus, in this manuscript, I try to find the missing link between spine homeostasis and the serotonergic system. The hypothesis is as follows. First, stress reduces the number of spines. Since spine homeostasis is tightly regulated by the serotonergic system, the spine loss is compensated by activated serotonergic system in normal conditions. However, various factors, such as genetic predispositions and heavy stress, decrease the resilience of spine homeostasis. In such conditions, the serotonergic system cannot compensate spine homeostasis anymore, leading to disrupted spine homeostasis. Finally, disrupted spine homeostasis results in depression. The characteristic point of this hypothesis is that it can monistically explain the pathogenesis of depression, where disturbance of spine homeostasis is the main cause. PMID:23631853

Sato, Kohji

2013-07-01

258

[Depression in schizophrenia].  

PubMed

Depressive symptoms are frequent during schizophrenia. Depression occurs in the course of a schizo affective psychose or in the course of a schizophrenia (either with acute psychotic symptoms, either without acute psychotic symptoms). Differentiating depression from negative symptoms of schizophrenia or from antipsychotic drug induced side effects can be difficult. The question to know whether depression is intrinsic to the disease process itself whether it is secondary to the schizophrenic process is still a matter of inquiry. Efficacy of antidepressive drugs during depression in schizophrenia remains a matter of controversy. Depression increases the risk for pejorative evolution and for suicide in schizophrenia. PMID:2028202

Rigaud, A S

1991-03-01

259

Freeze tolerance and cryoprotection in caterpillars of the giant leopard moth ( Ecpantheria scribonia Lepidoptera: Arctiidae)  

Microsoft Academic Search

1. The giant leopard moth (Ecpantheria scribonia) caterpillars were collected during October in Pennsylvania (USA) in order to measure indicators of cold hardiness.2. The supercooling point rose 2–4°C with cold acclimation (3°C) but this change missed statistical significance (P=0.0653). Hemolymph osmolality and glycerol also rose over 50% and 4.5×, respectively.3. All caterpillars initially survived freezing at ?3°C for 5 days

Jack R. Layne

2005-01-01

260

Evidence for a role of raffinose in stabilizing photosystem II during freeze–thaw cycles  

Microsoft Academic Search

A role of non-reducing sugars like sucrose and raffinose in the protection of plant cells against damage during freezing has\\u000a been proposed for many species, but reports on physiological effects are conflicting. Non-aqueous fractionation of mesophyll\\u000a cell compartments in Arabidopsis thaliana was used to show that sucrose and raffinose accumulate in plastids during low temperatures, pointing to a physiological role

Markus Knaupp; Kumud B. Mishra; Ladislav Nedbal; Arnd G. Heyer

261

Freezing and ice crystals formed in a cylindrical food model: part II. Comparison between freezing at atmospheric pressure and pressure-shift freezing  

Microsoft Academic Search

Cylindrical gelatin gels were pressure-shift frozen at different pressure levels (100, 150 and 200 MPa). Temperature and pressure profiles were compared and the maximum supercooling obtained after pressure release was evaluated. A comparison between the freezing steps at atmospheric pressure and those of pressure-shift freezing was carried out to compare the time steps during the processes. The degree of supercooling

D. Chevalier; A. Le Bail; M. Ghoul

2000-01-01

262

Transmembrane ion distribution during recovery from freezing in the woolly bear caterpillar Pyrrharctia isabella (Lepidoptera: Arctiidae).  

PubMed

During extracellular freezing, solutes in the haemolymph are concentrated, resulting in osmotic dehydration of the cells, which must be reversed upon thawing. Here, we used freeze tolerant Pyrrharctia isabella (Lepidoptera: Arctiidae) larvae to examine the processes of ion redistribution after thawing. To investigate the effect of the intensity of cold exposure on ion redistribution after thawing, we exposed caterpillars to -14°C, -20°C or -30°C for 35h. To investigate the effect of duration of cold exposure on ion redistribution after thawing, we exposed the caterpillars to -14°C for up to 6 weeks while sampling several time points. The concentrations of Na(+), K(+), Mg(2+) and Ca(2+) were measured after thawing in the haemolymph, fat body, muscle, midgut tissue and hindgut tissue. Being frozen for long durations (>3 weeks) or at low temperatures (-30°C) both result in 100% mortality, although different ions and tissues appear to be affected by each treatment. Both water distribution and ion content changes were detected after thawing, with the largest effects seen in the fat body and midgut tissue. Magnesium homeostasis appears to be vital for post-freeze survival in these larvae. The movement of ions during thawing lagged behind the movement of water, and ion homeostasis was not restored within the same time frame as water homeostasis. Failure to regain ion homeostasis after thawing is therefore implicated in mortality of freeze tolerant insects. PMID:21575641

Boardman, Leigh; Terblanche, John S; Sinclair, Brent J

2011-08-01

263

Language use of depressed and depression-vulnerable college students  

E-print Network

Language use of depressed and depression-vulnerable college students Stephanie S. Rude, Eva-depressed, formerly-depressed, and never-depressed college students were examined for differences in language with depression is Emil Durkheim's (1951) social integration/disengagement model of suicide. This model posits

Pillow, Jonathan

264

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, ...

265

Background to Depression  

NSDL National Science Digital Library

Although writers have described episodes of depression since antiquity, only recently have we recognized that the depressive disorders are among the most common and disabling medical conditions throughout the world.

2009-04-14

266

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. PMID:22754217

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

2012-01-01

267

Depression in Women  

MedlinePLUS

... wanting to eat at all Thoughts of suicide, suicide attempts Aches or pains, headaches, cramps, or digestive problems What causes depression in women? Several factors may contribute to depression ...

268

Infrared freezing of Euclidean QCD observables  

SciTech Connect

We consider the leading one-chain term in a skeleton expansion for QCD observables and show that for energies Q{sup 2}>{lambda}{sup 2}, where Q{sup 2}={lambda}{sup 2} is the Landau pole of the coupling, the skeleton expansion result is equivalent to the standard Borel integral representation, with ambiguities related to infrared (IR) renormalons. For Q{sup 2}<{lambda}{sup 2} the skeleton expansion result is equivalent to a previously proposed modified Borel representation where the ambiguities are connected with ultraviolet (UV) renormalons. We investigate the Q{sup 2}-dependence of the perturbative corrections to the Adler-D function, the GLS sum rule and the polarized and unpolarized Bjorken sum rules. In all these cases the one-chain result changes sign in the vicinity of Q{sup 2}={lambda}{sup 2}, and then exhibits freezing behavior, vanishing at Q{sup 2}=0. Finiteness at Q{sup 2}={lambda}{sup 2} implies specific relations between the residues of IR and UV renormalon singularities in the Borel plane. These relations, only one of which has previously been noted (though it remained unexplained), are shown to follow from the continuity of the characteristic function in the skeleton expansion. By considering the compensation of nonperturbative and perturbative ambiguities we are led to a result for the Q{sup 2}-dependence of these observables at all Q{sup 2}, in which there is a single undetermined nonperturbative parameter, and which involves the skeleton expansion characteristic function. The observables freeze to zero in the infrared. We briefly consider the freezing behavior of the Minkowskian R{sub e{sup +}}{sub e{sup -}} ratio.

Brooks, Paul M.; Maxwell, C. J. [Institute for Particle Physics Phenomenology, University of Durham, South Road, DH1 3LE (United Kingdom)

2006-09-15

269

The Ammonia Freeze Explosion (AFEX) process  

SciTech Connect

The Ammonia Freeze Explosion (AFEX) process treats lignocellulose with high-pressure liquid ammonia, and then explosively releases the pressure. The combined chemical effect (cellulose decrystallization) and physical effect (increased accessible surface area) dramatically increase lignocellulose susceptibility to enzymatic attack. There are many adjustable parameters in the AFEX process: ammonia loading, water loading, temperature, time, blowdown pressure, and number of treatments. The effect of these parameters on enzymatic susceptibility was explored for three materials: Coastal bermudagrass, bagasse, and newspaper. Nearly quantitative sugar yields were demonstrated for Coastal bermudagrass and bagasse, using a very low enzyme loading (5 IU/g). Newspaper proved to be much more resistant to enzymatic hydrolysis.

Holtzapple, M.T.; Jae-Hoon Jun; Ganesh Ashok; Patibandla, S.L.; Dale, B.E. [Texas A& M Univ., College Station, TX (United States)

1991-12-31

270

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

271

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 (East Patchogue, NY)

2012-01-24

272

Air-cooled steam condensers non-freeze warranties  

SciTech Connect

What this paper is suggesting is the seller quote a condenser package with a LIMITED NON-FREEZE WARRANTY. Relieve the inexperienced buyer of the responsibility for selecting freeze protection design options. The seller cannot afford to over-design because of the added costs and the need for a competitive price. Yet he cannot under-design and allow the condenser tubes to freeze periodically and then pay the repair bills in accordance with the warranty.

Larinoff, M.W.

1995-09-01

273

Clinical and Molecular Genetics of Psychotic Depression  

PubMed Central

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

2013-01-01

274

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

275

THE DEPRESSION IN ADOLESCENCE  

Microsoft Academic Search

This work analyzes depression in adolescence from a perspective of psychopathology which discusses psychoanalysis theory and biological psychiatry. Within this context, it is used the term of depression and the promise of cure through the adjustment of neuro-hormonal deficits which are expected to be offset by medications. Psychoanalysis fosters a differentiation between the terms depression and melancholia and correlates the

Kátia Cristine; Cavalcante Monteiro

276

DEPRESSION IN ADOLESCENT RUNAWAYS  

Microsoft Academic Search

The aim of this study was to determine the depressive and self esteem scores among Malaysian runaways. Forty-four (44) identified runaways from 4 Juvenile Homes in Kuala Lumpur were asked to complete Kovac's Child Depressive Inventory (CDI) and Coppersmith's Self Esteeln Inventory. The results showed that 88.6 % of them had high depressive scores on the CDI with a mean

Nor Hamidah Salleh; Kasmini Kassim

1995-01-01

277

Die Genetik der Depression  

Microsoft Academic Search

Summary Earlyonset forms of depression are on the rise and affected children often are seriously impaired in their per? sonal and academic development. There is convincing evidence to show that unipolar depression and bipolar disorder are substantially influenced by genetic factors. Unfortunately studies of pediatric depression are somewhat limited compared with research in adults. Various approches including linkageand association studies

Regina Hünnerkopf; KlausPeter Lesch

278

Depression on Dialysis  

Microsoft Academic Search

Depression is the most common psychopathological condition among patients with end-stage renal disease (ESRD), yet it is still under-recognized and misdiagnosed. Depression reduces quality of life and has a negative clinical impact upon sufferers with chronic illness, including ESRD. This article discusses the negative effects of depression among the ESRD population treated with dialysis, the prevalence of the condition, the

Joseph Chilcot; David Wellsted; Maria Da Silva-Gane; Ken Farrington

2008-01-01

279

Psychosocial causes of depression.  

PubMed

Research has consistently determined that women have higher rates of depression than men. It is possible that the sex ratio of depression incidence varies according to time and place, and that this variation is a reflection of women's variable social circumstances. However, further research is needed to determine a convincing explanation for women's greater susceptibility to depression. PMID:11279872

Bebbington, P E

1999-01-01

280

Motivational deficit in depression  

Microsoft Academic Search

It was recently hypothesized that depression primarily is a motivational deficit, where motivation is defined as the product of expectancies and values. This hypothesis has been supported by literature indicating that depressives possess pessimistic expectancies or low outcome values. The present experiments directly tested the motivational hypothesis of depression by measuring both expectancies and absolute values. Experiment 1 supported the

Christopher Layne; James Merry; James Christian; Paul Ginn

1982-01-01

281

Food freezing with simultaneous surface dehydration: approximate prediction of weight loss during freezing and storage  

Microsoft Academic Search

Weight loss of unpackaged foods during freezing and later storage is an important quality and economic issue. It is originated on surface ice sublimation due to differences in water activity between food surface and the refrigerating air. Weight loss rate is determined by refrigerating conditions and product characteristics. The modelling of this phenomenon has merited very little attention; at present

Laura A. Campañone; Viviana O. Salvadori; Rodolfo H. Mascheroni

2005-01-01

282

Importance of Depression in Diabetes.  

ERIC Educational Resources Information Center

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

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

283

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. PMID:22254168

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

284

Reversible Photoinhibition in Antarctic Moss during Freezing and Thawing.  

PubMed

Tolerance of antarctic moss to freezing and thawing stress was investigated using chlorophyll a fluorescence. Freezing in darkness caused reductions in Fv/Fm (ratio of variable to maximum fluorescence) and Fo (initial fluorescence) that were reversible upon thawing. Reductions in Fv/Fm and Fo during freezing in darkness indicate a reduction in the potential efficiency of photosystem II that may be due to conformational changes in pigment-protein complexes due to desiccation associated with freezing. The absorption of light during freezing further reduced Fv/Fm and Fo but was also reversible. Using dithiothreitol (DTT), which inhibits the formation of the carotenoid zeaxanthin, we found reduced flurorescence quenching during freezing and reduced concentrations of zeaxanthin and antheraxanthin after freezing in DTT-treated moss. Reduced concentrations of zeaxanthin and antheraxanthin in DTT-treated moss were partially associated with reductions in nonphotochemical fluorescence quenching. The reversible photoinhibition observed in antarctic moss during freezing indicates the existence of processes that protect from photoinhibitory damage in environments where freezing temperatures occur in conjunction with high solar radiation levels. These processes may limit the need for repair cycles that require temperatures favorable for enzyme activity. PMID:12228644

Lovelock, C. E.; Jackson, A. E.; Melick, D. R.; Seppelt, R. D.

1995-11-01

285

Anoxia tolerance and freeze tolerance in hatchling turtles.  

PubMed

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

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

2005-04-01

286

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

287

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

288

Attentional Biases for Negative Interpersonal Stimuli in Clinical Depression  

Microsoft Academic Search

An information-processing paradigm was used to examine attentional biases in clinically depressed participants, participants with generalized anxiety disorder (GAD), and nonpsychiatric control participants for faces expressing sadness, anger, and happiness. Faces were presented for 1,000 ms, at which point depressed participants had directed their attention selectively to depression-relevant (i.e., sad) faces. This attentional bias was specific to the emotion of

Ian H. Gotlib; Elena Krasnoperova; Dana Neubauer Yue; Jutta Joormann

2004-01-01

289

In-line multipoint near-infrared spectroscopy for moisture content quantification during freeze-drying.  

PubMed

During the past decade, near-infrared (NIR) spectroscopy has been applied for in-line moisture content quantification during a freeze-drying process. However, NIR has been used as a single-vial technique and thus is not representative of the entire batch. This has been considered as one of the main barriers for NIR spectroscopy becoming widely used in process analytical technology (PAT) for freeze-drying. Clearly it would be essential to monitor samples that reliably represent the whole batch. The present study evaluated multipoint NIR spectroscopy for in-line moisture content quantification during a freeze-drying process. Aqueous sucrose solutions were used as model formulations. NIR data was calibrated to predict the moisture content using partial least-squares (PLS) regression with Karl Fischer titration being used as a reference method. PLS calibrations resulted in root-mean-square error of prediction (RMSEP) values lower than 0.13%. Three noncontact, diffuse reflectance NIR probe heads were positioned on the freeze-dryer shelf to measure the moisture content in a noninvasive manner, through the side of the glass vials. The results showed that the detection of unequal sublimation rates within a freeze-dryer shelf was possible with the multipoint NIR system in use. Furthermore, in-line moisture content quantification was reliable especially toward the end of the process. These findings indicate that the use of multipoint NIR spectroscopy can achieve representative quantification of moisture content and hence a drying end point determination to a desired residual moisture level. PMID:23351045

Kauppinen, Ari; Toiviainen, Maunu; Korhonen, Ossi; Aaltonen, Jaakko; Järvinen, Kristiina; Paaso, Janne; Juuti, Mikko; Ketolainen, Jarkko

2013-02-19

290

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

PubMed

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

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

2014-11-01

291

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

Microsoft Academic Search

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

THOMAS A. CHURCHILL; KENNETH B. STOREY

292

Perceptions of Depression among Never-Depressed and Recovered-Depressed People  

Microsoft Academic Search

We assessed perceptions of the impact of depression among two groups of currently nondepressed adults (Beck Depression Inventory score = 9). The recovered-depressed (RD) participants (n = 25) had a history of major depressive disorder but had been recovered for at least 2 months since the most recent depressive episode. Never-depressed (ND) participants (n = 25) had no history of

Lindsey Kirk; David A. F. Haaga; Ari Solomon; Cindy Brody

2000-01-01

293

Cytoplasmic structure in organotypic cultures of rat hippocampus prepared by rapid freezing and freeze-substitution fixation.  

PubMed

We have compared rapid freezing followed by freeze-substitution fixation with conventional aldehyde fixation as preparative methods for the electron microscopic study of organotypic cultures of neonatal rat hippocampus. Rapid freezing by contact with a copper block chilled by liquid helium was accomplished without mechanical distortion of superficial structures, and preserved structure to a depth of at least 20 microns without visible ice crystals. Freeze-substitution fixation in acetone/osmium tetroxide, followed by en bloc staining with tannic acid and uranyl acetate, provided satisfactory staining of cytoplasm and organelles. While both preparative techniques yielded generally satisfactory results, rapid freezing provided much better preservation of astrocytic lysosomal inclusions, and afforded new views of intermediate filament substructure. Rapid freezing and freeze-substitution fixation seemed especially well suited to the preservation of short filamentous proteins, such as those forming the membrane cytoskeleton of dendritic spines or those associated with synaptic vesicles. The combination of rapid freezing methods and organotypic culture provides an opportunity to examine cytoplasmic structure in tissue from deep regions of the brain which had previously been inaccessible to rapid freezing techniques. PMID:8497806

Pozzo Miller, L D; Landis, D M

1993-03-01

294

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

PubMed

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

Malone, S R; Ashworth, E N

1991-03-01

295

Depression during pregnancy  

PubMed Central

OBJECTIVE To review existing literature on depression during pregnancy and to provide information for family physicians in order to promote early detection and treatment. QUALITY OF EVIDENCE MEDLINE was searched from January 1989 through August 2004 using the key words depression, pregnancy, prenatal, and antenatal. Articles focusing on depression during pregnancy were chosen for review; these articles were based on expert opinion (level III evidence) and prospective studies (level II evidence). MAIN MESSAGE Pregnancy does not safeguard women against depressive illness. The Edinburgh Postnatal Depression Scale is an effective screening tool for identifying women with depressive symptoms during pregnancy. Once diagnosed with major depression, these patients need to be monitored closely for up to a year after delivery. Patients with mild-to-moderate illness should be referred for psychotherapy. More severely ill patients might require additional treatment with antidepressants. The most commonly used antidepressants are selective serotonin reuptake inhibitors and the serotonin and norepinephrine reuptake inhibitor, venlafaxine. For each patient, risk of treatment with an antidepressant needs to be compared with risk of not treating her depressive illness. CONCLUSION Early detection of depression during pregnancy is critical because depression can adversely affect birth outcomes and neonatal health and, if left untreated, can persist after the birth. Untreated postpartum depression can impair mother-infant attachments and have cognitive, emotional, and behavioural consequences for children. PMID:16121830

Ryan, Deirdre; Milis, Lisa; Misri, Nicholas

2005-01-01

296

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. PMID:22305766

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

2012-01-01

297

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

298

Dimensionality of coping and its relation to depression.  

PubMed

The dimensionality of coping, as measured by 65 items from 3 commonly used instruments, and the relation of coping and stress to concurrent and future depression were studied in a community sample of 742 older (greater than or equal to 50 years old) adults. Measures of coping, stress, and depression were obtained at 2 time points over a 2-year period. Depression was assessed by symptom checklist and by diagnostic interview. Three coping factors--Cognitive Self-Control, Ineffective Escapism, and Solace Seeking--that had adequate psychometric properties and accounted for 25% of the total item variance were identified. Ineffective Escapism was associated with current depression and had a direct and interactive effect on future depression, exacerbating the negative impact of stress rather than acting as a buffer. Although Cognitive Self-Control was unrelated to either concurrent or future depression, Solace Seeking significantly buffered the effect of stress in predicting a future diagnosis of depression. Stress and initial depression level predicted both measures of future depression. Gender (being female) predicted the future diagnosis of depression but not the increase of depressive symptoms. PMID:2324939

Rohde, P; Lewinsohn, P M; Tilson, M; Seeley, J R

1990-03-01

299

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. PMID:22777309

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

2014-01-01

300

Prevalence of depression and anxiety among cancer patients  

PubMed Central

Background: Depression and anxiety had negative effects on the quality of life of cancer patients, thus hospital anxiety and depression scale (HADS) is a useful instrument for screening these problems. This research was performed to assess the prevalence of their anxiety and depression. Methods: From 2012-2013, one hundred fifty patients with recent diagnosis of different cancers in Babol, Iran were assessed. A presumptive diagnosis of anxiety and depression was based on a four point 14-item HADS. The score of 0-7 means without clinical symptoms of anxiety or depression, 8-10 mild and 11-21 symptomatic anxiety or depression. The data were collected and analyzed. Results: Forty-four (29.3%) patients had mild anxiety, 25 (16.7%) symptomatic anxiety but mild and symptomatic depression were seen in 40 (26.7%) and 32 (21.3%) patients, respectively. There were significant relationships between anxiety, depression and the age group of the patients with higher frequency in older ages. There were significant relationships between anxiety and depression with the type of cancer and type of treatment. Breast and stomach cancer patients had the highest prevalence of anxiety and depression and the higher prevalence was observed in the patients who received chemotherapy as the single treatment. Conclusion: The results show that patients with breast and stomach cancer had the highest prevalence of anxiety and depression among all others cancer patients. PMID:25202445

Nikbakhsh, Novin; Moudi, Sussan; Abbasian, Setareh; Khafri, Soraya

2014-01-01

301

Freeze-fracture cytochemistry: localization of wheat-germ agglutinin and concanavalin A binding sites on freeze-fractured pancreatic cells  

PubMed Central

The combined application of thin-section and critical-point-drying "fracture-label" is used to determine the pattern of distribution and partition of wheat-germ agglutinin and concanavalin A binding sites on the membrane faces of freeze-fractured exocrine and endocrine rat pancreatic cells. Whereas the exoplasmic face of plasma membrane is preferentially labeled by both lectins, the endoplasmic reticulum and nuclear envelope are strongly and uniformly labeled by concanavalin A but not by wheat-germ agglutinin. The results support current views in the glycosylation of membrane proteins and do not support the backflow of sialidated glycoproteins to the endoplasmic reticulum. PMID:7031067

1981-01-01

302

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. PMID:23617306

2013-01-01

303

Systematics of Kinetic Freeze-out Properties in High Energy Collisions from STAR  

E-print Network

The main aim of the RHIC Beam Energy Scan (BES) program is to explore the QCD phase diagram which includes search for a possible QCD critical point and the phase boundary between QGP and hadronic phase. We report the collision energy and centrality dependence of kinetic freeze-out properties from the measured mid-rapidity ($|y|temperature $T_{\\rm{kin}}$ and average collective velocity $\\langle \\beta \\rangle$ parameters are extracted from blast-wave fits to the identified hadron spectra and systematically compared with the results from other collision energies including those at AGS, SPS and LHC. It is found that all results fall into an anti-correlation band in the 2-dimension ($T_{\\rm{kin}}$, $\\langle \\beta \\rangle$) distribution: the largest value of collective velocity and lowest temperature is reached in the most central collisions at the highest collision energy. The energy dependence of these freeze-out parameters are discussed.

Lokesh Kumar

2014-08-19

304

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

305

ORIGINAL PAPER Effect of freezing-thawing on nitrogen mineralization  

E-print Network

ORIGINAL PAPER Effect of freezing-thawing on nitrogen mineralization in vegetation soils of four the effect of freezing-thawing on nitrogen (N) mineralization of four vegetation soils from typical . Soil nitrogen mineralization . Soil water content . Temperate forest . Changbai Mountain 1 Introduction

Boyer, Edmond

306

Microwave freeze drying of sea cucumber ( Stichopus japonicus)  

Microsoft Academic Search

Freeze drying (FD) yields the best quality of dried sea cucumber but at the cost of long drying time and also the overall cost. Air drying (AD) gives an unacceptably poor quality product. To achieve faster drying along with a high quality product a microwave freeze drying (MFD) technique was developed to dry sea cucumbers. The relationship between corona discharge

Xu Duan; Min Zhang; Arun S. Mujumdar; Shaojin Wang

2010-01-01

307

Prospective Primary School Teachers' Perceptions on Boiling and Freezing  

ERIC Educational Resources Information Center

The aim of this study was to investigate the perceptions of prospective primary school teachers on the physical state of water during the processes of boiling and freezing. There were three stages in the investigation: First, open-ended questions concerning the boiling and freezing of water were given to two groups of prospective primary school…

Senocak, Erdal

2009-01-01

308

Observation of a freezing drizzle episode: A case study  

NASA Astrophysics Data System (ADS)

On 5 February 2012 an episode of freezing precipitation took place in the Guadarrama Mountains, at the center of the Iberian Peninsula. This precipitation affected high elevations, where temperatures remained below freezing because of snow cover that had accumulated from snowfall during the previous days. The case study was recorded by surface synoptic observations (SYNOP) at Navacerrada Pass meteorological observatory (belonging to the National Weather Service of Spain). To study winter cloud systems during the TEcoAgua project, a multichannel ground-based microwave radiometer (MMWR), Micro Rain Radar (MRR-2), and isothermal cloud chamber were installed in the study area, thus permitting the monitoring of the freezing precipitation event. Analysis using Meteosat Second Generation (MSG) satellite data and observations permitted the determination of factors that triggered the freezing precipitation event. Freezing drizzle was interspersed with the passage of a warm and cold front. During frontal passage, mid-level clouds inhibited the generation of freezing drizzle, with snowfall recorded in the study area. However, during the period between the two fronts, an absence of mid-level clouds permitted low-level orographic clouds to persist upwind of the mountain system, producing freezing drizzle at the surface. The decisive factors for the generation of freezing drizzle were high humidity at low levels, weak mesoscale updrafts caused by the topography, stability at mid levels, cloud-top temperatures warmer than - 15 °C, and low concentrations of ice nuclei.

Fernández-González, S.; Valero, F.; Sanchez, Jose L.; Gascón, E.; López, L.; García-Ortega, E.; Merino, A.

2014-11-01

309

Corn Seed Germination and Vigor Following Freezing during Seed Development  

Microsoft Academic Search

The potential for an early autumn frost to reduce corn (Zea mays L.) seed quality is a concern for seed producers. This study evaluated the effect of freezing rate, freezing temperature (26, 211C) and duration (4, 6 h), ear attachment, and endosperm composition on seed germination and vigor (accelerated aging (AA) and cold test) during seed development and maturation of

James Woltz; Dennis M. TeKrony; Dennis B. Egli

2006-01-01

310

In Vivo Detection of Membrane Injury at Freezing Temperatures  

PubMed Central

The release of hydrogen cyanide from Amelanchier alnifolia was monitored at 30 C and ?10 C following lethal freezing at both slow and fast rates. Assuming that hydrogen cyanide release indicates membrane damage, it was concluded that during a fatal freeze-thaw cycle membrane damage occurred during cell contraction and, therefore, was not dependent upon membrane area expansion during thawing. PMID:16661397

Stout, Darryl G.; Majak, Walter; Reaney, Martin

1980-01-01

311

In vivo detection of membrane injury at freezing temperatures.  

PubMed

The release of hydrogen cyanide from Amelanchier alnifolia was monitored at 30 C and -10 C following lethal freezing at both slow and fast rates. Assuming that hydrogen cyanide release indicates membrane damage, it was concluded that during a fatal freeze-thaw cycle membrane damage occurred during cell contraction and, therefore, was not dependent upon membrane area expansion during thawing. PMID:16661397

Stout, D G; Majak, W; Reaney, M

1980-07-01

312

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

313

Study of Ice Cream Freezing Process after Treatment with Ultrasound  

Microsoft Academic Search

Application of power ultrasound to Food freezing is a relatively new subject, cavitations is the most significant power which can not only lead to the production of gas bubbles in ice ream but also the occurrence of micro streaming, also it can promote ice nucleation to accelerate the heat and mass transfer process accompanying the freeze process. In this work

A. Mortazavi; F. Tabatabaie

314

Modeling solute segregation during freezing of peatland waters  

Microsoft Academic Search

Freezing of the shallow water in a peatland causes the downward movement of solutes. Field and laboratory data demonstrate that a considerable portion of the solutes are driven into the top soil from the overlying water by freezing. Such solute redistribution phenomena in peatlands are of interest for establishing the geochronology of deposits and determining the nature of pollutant burial.

Robert H. Kadlec; Xiang-Ming Li; Gerald B. Cotten

1988-01-01

315

Freeze-Outs: Transcontinental Analysis and Reform Proposals  

Microsoft Academic Search

One of the most crucial, but systematically neglected, comparative differences between corporate law systems in Europe and in the United States concerns the regulations governing freeze-out transactions in listed corporations. Freeze-outs can be defined as transactions in which the controlling shareholder exercises a legal right to buy out the shares of the minority, and consequently delists the corporation and brings

Marco Ventoruzzo

2010-01-01

316

Freezing of Barley Studied by Infrared Video Thermography  

Microsoft Academic Search

Freezing of barley (Hordeum vulgare), Hordeum murinum, and Holcus lanatus was studied using infrared video thermography. In the field, ice could enter H. lanatus leaves through hydathodes. In laboratory tests with barley, initially 0.4% of the leaf water froze, spreading in alternate strips of high and low freezing intensity longitudinally at 1 to 4 cm s21, and simultaneously spreading laterally

Roger S. Pearce; Michael P. Fuller

2001-01-01

317

Comparison of the New NPL Primary Standard Ag Fixed-Point Blackbody Source with the Primary Standard Fixed Point of PTB  

Microsoft Academic Search

Above the freezing point of silver (961.78 °C), the International Temperature Scale of 1990 is defined in terms of Planck's radiation law. The scale is maintained and disseminated using a validated and linear pyrometer in conjunction with a blackbody reference source at either the Ag, Au (1064.18 °C) or Cu (1084.62 °C) freezing point. In order to realize the scale

H. C. McEvoy; G. Machin; R. Friedrich; J. Hartmann; J. Hollandt

2003-01-01

318

Alcohol Use is Not Directly Related to the Perceived Control of Depressive Symptoms in Patients with Depressive Symptoms  

PubMed Central

Treatment-seeking patients (N?=?233) were recruited as they started a course of relapse prevention and coping with depression. The mean Beck depression inventory (BDI-II) score was 26 points, indicating a moderate degree of depression. The sample was recruited from different outpatient clinics and screened for alcohol-related problems with the alcohol use disorders identification test (AUDIT). Almost half of the total sample had a score on AUDIT >8 indicating an alcohol problem. The participants in this study did not undergo a clinical interview to check out if their symptoms, as assessed with BDI-II and AUDIT, were part of a formal diagnosis in accordance with the criteria in ICD 10 or DSM IV. A specific instrument, perceived uncontrollability of depression (UNCONTROL), was used to measure the persons’ perceived control of depressive symptoms; a set of statements about coping with depressive symptoms where high scores indicate lack of coping with the symptoms. Alcohol problems were not found to be significantly associated with the perceived control of ongoing depressive symptoms and did not moderate the relationship between depressive symptoms and the perceived control of depressive symptoms. The results question the assumption that alcohol use is related to coping with depressive symptoms in patients with alcohol abuse and depressive symptoms. PMID:24723895

Skule, Cecilie; Dallavara Lending, Hilde; Ulleberg, Pal; Berge, Torkil; Egeland, Jens; Landr?, Nils Inge

2014-01-01

319

Alcohol Use is Not Directly Related to the Perceived Control of Depressive Symptoms in Patients with Depressive Symptoms.  

PubMed

Treatment-seeking patients (N?=?233) were recruited as they started a course of relapse prevention and coping with depression. The mean Beck depression inventory (BDI-II) score was 26 points, indicating a moderate degree of depression. The sample was recruited from different outpatient clinics and screened for alcohol-related problems with the alcohol use disorders identification test (AUDIT). Almost half of the total sample had a score on AUDIT >8 indicating an alcohol problem. The participants in this study did not undergo a clinical interview to check out if their symptoms, as assessed with BDI-II and AUDIT, were part of a formal diagnosis in accordance with the criteria in ICD 10 or DSM IV. A specific instrument, perceived uncontrollability of depression (UNCONTROL), was used to measure the persons' perceived control of depressive symptoms; a set of statements about coping with depressive symptoms where high scores indicate lack of coping with the symptoms. Alcohol problems were not found to be significantly associated with the perceived control of ongoing depressive symptoms and did not moderate the relationship between depressive symptoms and the perceived control of depressive symptoms. The results question the assumption that alcohol use is related to coping with depressive symptoms in patients with alcohol abuse and depressive symptoms. PMID:24723895

Skule, Cecilie; Dallavara Lending, Hilde; Ulleberg, Pål; Berge, Torkil; Egeland, Jens; Landrø, Nils Inge

2014-01-01

320

The depressive situation.  

PubMed

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

A Jacobs, Kerrin

2013-01-01

321

The depressive situation  

PubMed Central

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

A. Jacobs, Kerrin

2013-01-01

322

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

323

Hot water can freeze faster than cold?!?  

E-print Network

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

Jeng, M

2005-01-01

324

Solar desalination by freezing and distillation  

NASA Astrophysics Data System (ADS)

It is noted that among seawater desalination processes the absorption-freeze vapor compression processes based on the thermal heat pump, although untested commercially and still in the development stage, appears technically and economically an attractive application of low-grade (exergy) solar heat. The distillation processes proposed here may be conveniently powered by low-grade solar heat (from flat plate solar collectors). It is expected that the scaling problem will be insignificant in comparison with that encountered in the conventional multistage flash process. The novel feature here is the use of enlarged capacity for heat exchange between distillate and brine via latent heat of solid-liquid phase change of a suitable hydrophobic intermediate heat transfer material.

Kvajic, G.

325

Hadron Freeze-Out and Unruh Radiation  

E-print Network

We consider hadron production in high energy collisions as an Unruh radiation phenomenon. This mechanism describes the production pattern of newly formed hadrons and is directly applicable at vanishing baryochemical potential, mu = 0. It had already been found to correctly yield the hadronisation temperature, T_h = sqrt(sigma / 2 pi) = 165 MeV in terms of the string tension sigma. Here we show that the Unruh mechanism also predicts hadronic freeze-out conditions, giving s/T_h^3 = 3 pi^2 / 4 = 7.4 in terms of the entropy density s and E/N = \\sqrt(2 pi sigma) = 1.09 for the average energy per hadron. These predictions provide a theoretical basis for previous phenomenological results and are also in accord with recent lattice studies.

Paolo Castorina; Alfredo Iorio; Helmut Satz

2014-09-10

326

Hadron Freeze-Out and Unruh Radiation  

E-print Network

We consider hadron production in high energy collisions as an Unruh radiation phenomenon. This mechanism describes the production pattern of newly formed hadrons and is directly applicable at vanishing baryochemical potential, mu = 0. It had already been found to correctly yield the hadronisation temperature, T_h = sqrt(sigma / 2 pi) = 165 MeV in terms of the string tension sigma. Here we show that the Unruh mechanism also predicts hadronic freeze-out conditions, giving s/T_h^3 = 3 pi^2 / 4 = 7.4 in terms of the entropy density s and E/N = \\sqrt(2 pi sigma) = 1.09 for the average energy per hadron. These predictions provide a theoretical basis for previous phenomenological results and are also in accord with recent lattice studies.

Castorina, Paolo; Satz, Helmut

2014-01-01

327

Free-energy functional for freezing transitions: Hard sphere systems freezing into crystalline and amorphous structures  

E-print Network

A free-energy functional that contains both the symmetry conserved and symmetry broken parts of the direct pair correlation function has been used to investigate the freezing of a system of hard spheres into crystalline and amorphous structures. The freezing parameters for fluid-crystal transition have been found to be in very good agreement with the results found from simulations. We considered amorphous structures found from the molecular dynamics simulations at packing fractions $\\eta$ lower than the glass close packing fraction $\\eta_{J}$ and investigated their stability compared to that of a homogeneous fluid. The existence of free-energy minimum corresponding to a density distribution of overlapping Gaussians centered around an amorphous lattice depicts the deeply supercooled state with a heterogeneous density profile.

Swarn Lata Singh; Atul S. Bharadwaj; Yashwant Singh

2011-01-31

328

A search for the Mpemba effect: When hot water freezes faster then cold water  

E-print Network

An explanation for why hot water will sometime freeze more rapidly than cold water is offered. Two specimens of water from the same source will often have different spontaneous freezing temperatures; that is, the temperature at which freezing begins. When both specimens supercool and the spontaneous freezing temperature of the hot water is higher than that of the cold water, then the hot water will usually freeze first, if all other conditions are equal and remain so during cooling. The probability that the hot water will freeze first if it has the higher spontaneous freezing temperature will be larger for a larger difference in spontaneous freezing temperature. Heating the water may lower, raise or not change the spontaneous freezing temperature. The keys to observing hot water freezing before cold water are supercooling the water and having a significant difference in the spontaneous freezing temperature of the two water specimens. We observed hot water freezing before cold water 28 times in 28 attempts und...

Brownridge, James D

2010-01-01

329

9 CFR 381.66 - Temperatures and chilling and freezing procedures.  

Code of Federal Regulations, 2011 CFR

...Temperatures and chilling and freezing procedures. 381.66 Section...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Temperatures and chilling and freezing procedures. (a) General...necessary for chilling and freezing ready-to-cook...

2011-01-01

330

9 CFR 381.66 - Temperatures and chilling and freezing procedures.  

Code of Federal Regulations, 2012 CFR

...Temperatures and chilling and freezing procedures. 381.66 Section...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Temperatures and chilling and freezing procedures. (a) General...necessary for chilling and freezing ready-to-cook...

2012-01-01

331

9 CFR 381.66 - Temperatures and chilling and freezing procedures.  

Code of Federal Regulations, 2013 CFR

...Temperatures and chilling and freezing procedures. 381.66 Section...Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE...Temperatures and chilling and freezing procedures. (a) General...necessary for chilling and freezing ready-to-cook...

2013-01-01

332

Studying the emergence of depression and depressive symptoms during adolescence  

Microsoft Academic Search

The special issue on the emergence and maintenance of depression and depressive symptoms is introduced. The special issue considers two typically separate lines of research, one focusing on severe clinical depression and another on depressive symptoms. The biological, social, and cognitive factors contributing to the emergence of depression in adolescence are highlighted in this special issue.

Jeanne Brooks-Gunn; Anne C. Petersen

1991-01-01

333

Evaluation and Validation of the Messinger Freezing Fraction  

NASA Technical Reports Server (NTRS)

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

Anderson, David N.; Tsao, Jen-Ching

2005-01-01

334

Inoculation triggers freezing at high subzerotemperatures in a freeze-tolerant frog (Rana sylvatica)and insect (Eurosta solidaginis)  

E-print Network

sylvatica)and insect (Eurosta solidaginis) hcr R. LnyNr, Jn.l OhioUniversity- Belmont,45425National .Road.Inoculationtriggersfreezingat high subzerotemperaturesin a freeze-tolerantfrog (Rana sylvatica) and insdct(Eurosta solidaginis possibility in two freeze-tolerantanimals,the wood frog, Ranasylvatica, andthegoldenrodgall fly, Eurosta

Lee Jr., Richard E.

335

Feasibility of high pressure freezing with freeze substitution after long-term storage in chemical fixatives.  

PubMed

Fixation of biological samples is an important process especially related to histological and ultrastructural studies. Chemical fixation was the primary method of fixing tissue for transmission electron microscopy for many years, as it provides adequate preservation of the morphology of cells and organelles. High pressure freezing (HPF) and freeze substitution (FS) is a newer alternative method that rapidly freezes non-cryoprotected samples that are then slowly heated in the FS medium, allowing penetration of the tissue to insure adequate fixation. This study addresses several issues related to tissue preservation for electron microscopy. Using mice liver tissue as model the difference between samples fixed chemically or with HPF immediately after excision, or stored before chemical or HPF fixation were tested with specific focus on the nuclear membrane. Findings are that immediate HPF is the method of choice compared to chemical fixation. Of the chemical fixatives, immediate fixation with 2.5% glutaraldehyde (GA)/formaldehyde (FA) is the best in preserving membrane morphology, 2.5% GA can be used as alternative for stored and then chemically processed samples, with 10% formalin being suitable as a storage medium only if followed by HPF fixation. Overall, storage leads to lower ultrastructural preservation, but HPF with FS can minimize these artifacts relative to other processing protocols. PMID:23818457

Venter, Chantelle; Van Der Merwe, Christiaan Frederick; Oberholzer, Hester Magdalena; Bester, Megan Jean; Taute, Helena

2013-09-01

336

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

337

Embodied intervention reduce depression  

NASA Astrophysics Data System (ADS)

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

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

2011-10-01

338

Effects of freezing on the survival of Escherichia coli and Bacillus and response to UV and chlorine after freezing.  

PubMed

Escherichia coli (E. coli) and Bacillus megaterium bacteria were frozen at -15 degrees C using a freezer and a spray freezing method. The frozen Bacillus spores were also exposed to UV and free chlorine. An average of 4.7-log inactivation was obtained from the spray ice with 2-day storage time, while the freezer freezing only caused 0.84-log reduction with the same storage time. Significantly higher inactivation levels were observed for the E. coli cells with 2-day storage compared with those without storage. The spray freezing was found more effective in killing the E. coli cells, while more cells were sublethally injured by the freezer freezing. Freezing did not kill the Bacillus megaterium spores, but affected their response to UV and chlorine. Greater inactivation levels were observed at higher free chlorine doses or longer contact time, and the UV fluence-response curve showed initial rapid kill followed by tailing for the frozen spores. PMID:17571840

Gao, W; Smith, D W; Li, Y

2007-05-01

339

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

Microsoft Academic Search

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

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

2012-01-01

340

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

341

Comparative validity of three screening questionnaires for DSM-IV depressive disorders and physicians’ diagnoses  

Microsoft Academic Search

Background: The aim of this study was to compare the validity of the Hospital Anxiety and Depression Scale (HADS), the WHO (five) Well Being Index (WBI-5), the Patient Health Questionnaire (PHQ), and physicians’ recognition of depressive disorders, and to recommend specific cut-off points for clinical decision making. Methods: A total of 501 outpatients completed each of the three depression screening

Bernd Löwe; Robert L. Spitzer; Kerstin Gräfe; Kurt Kroenke; Andrea Quenter; Stephan Zipfel; Christine Buchholz; Steffen Witte; Wolfgang Herzog

2004-01-01

342

A Case of Elderly Manic-Depression with Dementia-Like Symptoms in a Manic Phase  

Microsoft Academic Search

The authors present the case of an elderly manic-depressive woman who showed dementia-like symptoms only in the manic phase. The reasons why occurrence of endogenous bipolar depression (manic-depression) in the elderly is comparatively rare are considered from the point of the possibilty of latent disturbance of the brain, presbyophrenia, and pseudodementia.

M. Kawai; K. Miyamoto; M. Miyamoto

1990-01-01

343

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

ERIC Educational Resources Information Center

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

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

2012-01-01

344

Face Emotion Processing in Depressed Children and Adolescents with and without Comorbid Conduct Disorder  

ERIC Educational Resources Information Center

Studies of adults with depression point to characteristic neurocognitive deficits, including differences in processing facial expressions. Few studies have examined face processing in juvenile depression, or taken account of other comorbid disorders. Three groups were compared: depressed children and adolescents with conduct disorder (n = 23),…

Schepman, Karen; Taylor, Eric; Collishaw, Stephan; Fombonne, Eric

2012-01-01

345

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

346

Metabolic mechanisms for anoxia tolerance and freezing survival in the intertidal gastropod, Littorina littorea.  

PubMed

The gastropod mollusk, Littorina littorea L., is a common inhabitant of the intertidal zone along rocky coastlines of the north Atlantic. This species has well-developed anoxia tolerance and freeze tolerance and is extensively used as a model for exploring the biochemical adaptations that support these tolerances as well as for toxicological studies aimed at identifying effective biomarkers of aquatic pollution. This article highlights our current understanding of the molecular mechanisms involved in anaerobiosis and freezing survival of periwinkles, particularly with respect to anoxia-induced metabolic rate depression. Analysis of foot muscle and hepatopancreas metabolism includes anoxia-responsive changes in enzyme regulation, signal transduction, gene expression, post-transcriptional regulation of mRNA, control of translation, and cytoprotective strategies including chaperones and antioxidant defenses. New studies describe the regulation of glucose-6-phosphate dehydrogenase by reversible protein phosphorylation, the role of microRNAs in suppressing mRNA translation in the hypometabolic state, modulation of glutathione S-transferase isozyme patterns, and the regulation of the unfolded protein response. PMID:23507570

Storey, Kenneth B; Lant, Benjamin; Anozie, Obiajulu O; Storey, Janet M

2013-08-01

347

Cognitive deficits in depression  

E-print Network

samples to patients with moderate to severe depression leaving us with little information about the cognitive deficits associated with mild depression; 3) small sample sizes; and, 4) the use of tests with unknown psychometric properties. The present... that more capacity to attend and concentrate is available when arousal is moderately high than when arousal is low; this is the crux of his Capacity Limitation Theory. Depression may cause an extremely low level of arousal that results in decreased...

Haines, Mary Ellen

2012-06-07

348

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

349

Legal Ethics and Depression  

E-print Network

Legal Ethi cs and Depression By Michael H. Hoeflich "no" in many, if not most cases. And herein lies the problem. Recent scientific studies have made it very clear that most forms of major depression have definite physical pathologies... that often involve progressive chemical and physical changes to the brain.5 Further, a substantial number of those individ- uals who suffer from major depression have a genetic predis- position to do so. In addition, stress, particularly stress that also...

Hoeflich, Michael H.

2005-09-01

350

Depression and smoking cessation  

Microsoft Academic Search

The aim of this paper is to examine whether depression, assessed using the Beck Depression Inventory, is related to smoking cessation motivation and self-efficacy. In a population sample of 1,547 Finnish men and 1,856 Finnish women, aged between 25–64 years, there were 34% male and 21% female current smokers. The current smokers had higher mean depression scores than former or

Ari Haukkala; Antti Uutela; Erkki Vartiainen; Alfred Mcalister; Paul Knekt

2000-01-01

351

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

352

Depression in adolescence.  

PubMed

Adolescence is an important developmental period for understanding the nature, course, and treatment of depression. Recent research concerned with depressive mood, syndromes, and disorders during adolescence is reviewed, including investigations of the prevalence, course, risk factors, and prevention and treatment programs for each of these three levels of depressive phenomena in adolescence. A broad biopsychosocial perspective on adolescent depression is recommended, and possible directions for future integrative research are proposed. Based on current research and knowledge, implications for research, program, and national policy are considered. PMID:8442570

Petersen, A C; Compas, B E; Brooks-Gunn, J; Stemmler, M; Ey, S; Grant, K E

1993-02-01

353

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

354

Water Relations of Pachysandra Leaves during Freezing and Thawing 1  

PubMed Central

The evergreen herb Pachysandra terminalis becomes moderately frost-hardy in winter. The water relations of its frost-hardy leaves were studied during a freeze-thaw cycle. Leaf water potentials, measured by psychrometry at subfreezing temperatures, were identical with those of ice, indicating equilibrium freezing. Microscopic observations showed extracellular freezing of tissue water. As evidenced by thermal analysis, the freezing process starts with the crystallization of a minor volume which was identified as apoplasmic water. The following long-lasting exotherm indicated slow export of water from the protoplasts driven by extracellular crystallization. In partially frozen leaves, the fractions of liquid water were measured at several subfreezing temperatures by nuclear magnetic resonance spectroscopy. They were consistently greater than those calculated from the osmotic potentials of cellular fluid, and the differences increased with decreasing temperature. About 50% of the differences could be abolished by freeze-killing of the leaf and was thus ascribed to the effect of a (negative) pressure reinforcing the osmotic potential. The persistent part of the differences may have reflected a matric component. At ?7°C, the absolute values of both potentials were ?1.7 megapascals each. The water relations of Pachysandra leaves clearly indicate nonideal equilibrium freezing where negative pressures and matric potentials contribute to the leaf water potential and thus alleviate freeze-dehydration of the tissue. ImagesFigure 1Figure 5 PMID:16668501

Zhu, Jian-Jun; Beck, Erwin

1991-01-01

355

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. PMID:24675792

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

2014-01-01

356

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

357

Influence of Depressive Symptoms on Dopaminergic Treatment of Parkinson's Disease  

PubMed Central

Introduction: Depressive symptoms are very common in patients with Parkinson’s disease (PD) and have a significant impact on the quality of life. Dopaminergic medication has been shown to have an influence on the development of depressive symptoms. Materials and methods: The present study analyzed two groups of non-demented patients with PD, with and without depressive symptoms, and reported the correlations between antiparkinsonian medication [specifically levodopa (l-DOPA) and dopaminergic agonists] with depressive symptoms. Results: A strong statistically significant positive correlation between l-DOPA dosages and the level of depressive symptoms has been revealed, suggesting that higher l-DOPA dosages correlate with a worsening of depressive status. No significant correlation was found with dopamine agonists. Discussion: The results of this study show that in patients with PD, higher l-DOPA dosages correlate with worse depressive symptoms. From this point of view, PD patients need to be better diagnosed with respect to depressive symptoms and need additional treatment adjustment when clinical manifestations of depression are present. Clinicians must be aware that dopaminergic drugs are not sufficient to alleviate depressive symptoms.

Hanganu, Alexandru; Degroot, Clotilde; Monchi, Oury; Bedetti, Christophe; Mejia-Constain, Beatriz; Lafontaine, Anne-Louise; Chouinard, Sylvain; Bruneau, Marie-Andree

2014-01-01

358

Heterogeneous freezing of droplets with immersed mineral dust particles - measurements and parameterization  

NASA Astrophysics Data System (ADS)

During the measurement campaign FROST (FReezing Of duST), LACIS (Leipzig Aerosol Cloud Interaction Simulator) was used to investigate the immersion freezing behavior of size selected, coated and uncoated Arizona Test Dust (ATD) particles with a mobility diameter of 300 nm. Particles were coated with succinic acid (C4H6O4), sulfuric acid (H2SO4) and ammonium sulfate ((NH4)2SO4). Ice fractions at mixed-phase cloud temperatures ranging from 233.15 K to 239.15 K (±0.60 K) were determined for all types of particles. In this temperature range, pure ATD particles and those coated with C4H6O4 or small amounts of H2SO4 were found to be the most efficient ice nuclei (IN). ATD particles coated with (NH4)2SO4 were the most inefficient IN. Since the supercooled droplets were highly diluted before freezing occurred, a freezing point suppression due to the soluble material on the particles (and therefore in the droplets) cannot explain this observation. Therefore, it is reasonable to assume that the coatings lead to particle surface alterations which cause the differences in the IN abilities. Two different theoretical approaches based on the stochastic and the singular hypotheses were applied to clarify and parameterize the freezing behavior of the particles investigated. Both approaches describe the experimentally determined results, yielding parameters that can subsequently be used to compare our results to those from other studies. However, we cannot clarify at the current state which of the two approaches correctly describes the investigated immersion freezing process. But both approaches confirm the assumption that the coatings lead to particle surface modifications lowering the nucleation efficiency. The stochastic approach interprets the reduction in nucleation rate from coating as primarily due to an increase in the thermodynamic barrier for ice formation (i.e., changes in interfacial free energies). The singular approach interprets the reduction as resulting from a reduced surface density of active sites.

Niedermeier, D.; Hartmann, S.; Shaw, R. A.; Covert, D.; Mentel, T. F.; Schneider, J.; Poulain, L.; Reitz, P.; Spindler, C.; Clauss, T.; Kiselev, A.; Hallbauer, E.; Wex, H.; Mildenberger, K.; Stratmann, F.

2010-04-01

359

Immersion freezing on mineral dust particles  

NASA Astrophysics Data System (ADS)

Mineral dust is considered to play a major role in ice cloud nucleation in the troposphere. More than 1.000 Tg of mineral dust are aerosolized from the ground every year, 1-10% of these reach the upper troposphere [1]. At an altitude of about 8 km ice residual particle analysis has shown that about 50% of all ice nuclei (IN) are mineral dust[2]. In principle, natural occurring dusts may either be IN-active themselves or are carriers of organic and/or biological IN. Up to now the ice nucleation, i.e. cloud glaciation, has not been quantized. However, different authors report a high IN-activity for many mineral dust samples, although a systematic comparison between different minerals is still missing. Therefore, we studied selected mineral dust samples which were characterized by X-ray diffraction, FTIR spectroscopy, and scanning electron microscopy before use. Oil immersion measurements were performed on the most common minerals, clay materials and volcanic ash. The median freezing temperatures range from -21°C up to homogenous freezing at 38°C. Even though quite a few dust samples show a reasonable high IN-activity, their median freezing temperatures are low compared to biological samples [3, 4]. Furthermore, heat treatment of the dusts was applied in order to decompose and to denaturize organic and/or biological surfactants. Finally, some dust samples had a high loss of activity and thus were subjects of further experiments. These mineral dust particles were suspended in water and after an incubation time were removed. In some cases the washing water had become IN-active, but lost its activity after enzymatic treatment. The observed high IN-activity can thus be explained by adsorbed biological materials. The results suggest that some mineral dusts are IN-active, and if it is not intrinsic they may even enhance IN-activity of organic and biological IN if these are adsorbed on the dust particle surface. A relatively high IN-activity of the pure mineral dusts was only observed in quartz, clays, and mixed natural dusts (ATD), which are mainly composed of SiO2 and clays. References. [1] C. S. Zender, R. L. Miller and I. Tegen, Eos Trans. AGU, 2004,85, 509. [2] K. A. Pratt, P. J. DeMott, J. R. French, Z. Wang, D. L. Westphal, A. J. Heymsfield, C. H. Twohy, A. J. Prenni, K. A. Prather, Nat. Geosci., 2009, 2, 397-400. [3] B. Pummer, H. Bauer, J. Bernardi, S. Bleicher and H. Grothe, Atmos. Chem. Phys., 2012, 12, 2541-2550. [4] V. T. J. Phillips, C. Andronache, B. Christner, C. E. Morris, D. C. Sands, A. Bansemer, A. Lauer, C. McNaughton and C. Seman, Biogeosciences, 2009, 6, 987-1014.

Zolles, Tobias; Grothe, Hinrich; Pummer, Bernhard

2013-04-01

360

Is Enceladus' Internal Ocean Doomed to Freeze?  

NASA Astrophysics Data System (ADS)

Enceladus is geologically hyperactive, with plumes of water vapor, other volatiles such as ammonia, and salty particles erupting from its South Polar Terrain. The plumes are spatially associated with a region of greatly increased local heat flux, with a total power output 15.8 × 3.1 GW spread over an area of 70,000 km2 (e.g., Spencer and Nimmo 2013, AREPS 41), corresponding to a regional heat flux of 180-270 mW m-2. Tidal strains of the magnitude only possible in an ice shell that is decoupled from a rocky interior by an internal ocean or regional sea are required to generate this much heat (e.g., Behounkova et al. 2012, Icarus 219). Yet, numerous studies conclude that Enceladus' ocean cannot be in present-day thermodynamic steady state with a conductive or convective ice I shell (e.g., Roberts and Nimmo 2008, Icarus 194; Behounkova et al. 2012). Regardless of where Enceladus' tidal heating is concentrated (i.e., the poles), and regardless of whether its outer ice I shell convects, Enceladus' ocean is predicted to freeze on a geologically rapid time scale, implying that activity on Enceladus is only a transient or episodic phenomenon. These arguments strictly apply only to pure water ice oceans, however. We have previously argued that if the presence of salts or ammonia is allowed for, the ocean may be cooler and can be maintained essentially permanently by tidal heating in the ice above (McKinnon and Barr 2008, LPS XXXIX). Here we elaborate on the conditions under which Enceladus' ocean can be stabilized or even increase in thickness due to present-day tidal heating within the ice shell and the presence of salts and ammonia, which we now know are there (Waite et al. 2009, Nature 460; Postberg et al. 2011, Nature 474). As previous work has found, we cannot explain the present-day heat flow, but there is no fundamental reason that Enceladus' ocean or sea should completely freeze for present-day orbital eccentricities.

McKinnon, W. B.; Barr, A. C.

2013-12-01

361

Viscosity Depressants for Coal Liquefaction  

NASA Technical Reports Server (NTRS)

Proposed process modification incorporates viscosity depressants to prevent coal from solidifying during liquefaction. Depressants reduce amount of heat needed to liquefy coal. Possible depressants are metallic soaps, such as stearate, and amides, such as stearamide and dimer acid amides.

Kalfayan, S. H.

1983-01-01

362

St. John's Wort and Depression  

MedlinePLUS

... help ensure coordinated and safe care. Top About Depression Depression is a medical condition that affects about ... the Science Says About St. John’s Wort for Depression Study results on the effectiveness of St. John’s ...

363

Major depression with psychotic features  

MedlinePLUS

Psychotic depression; Delusional depression ... The risk of suicide is much higher in people with depression with psychotic symptoms than in those without psychosis. You may need to stay in the hospital if you have ...

364

Freezing and Melting, Precipitation Type, and Numerical Weather Prediction  

NSDL National Science Digital Library

This Webcast 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.

Comet

2002-07-03

365

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

366

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. PMID:24737658

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

2014-06-01

367

Using the Persian-Language Version of the Beck Depression Inventory-II (BDI-II-Persian) for the Screening of Depression in Students.  

PubMed

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

Vasegh, Sasan; Baradaran, Nafiseh

2014-10-01

368

Incorporation of ( sup 14 C)-palmitate into lipids of Brassica cells during the induction of freezing tolerance  

SciTech Connect

Changes in plasma membrane lipid composition have been causally related to increased freezing tolerance. Studies of lipid metabolism during ABA induction of freezing tolerance in Brassica napus suspension cultures were undertaken. Cells were labeled with ({sup 14}C)-palmitate four days after transfer to fresh medium (control) or medium containing ABA (which increases freezing tolerance). At times between one and 20 hrs after labeling, ABA-treated cells incorporated almost twice the amount of label as controls cells. Approximately 80% of the radioactivity was associated with neutral lipids in ABA-treated cells and controls. Incorporation of label into total cellular polar lipids was 4.9 {times} 10{sup 5} dpm/mg protein for control cells and 1 {times} 10{sup 6} dpm/mg protein for cells transferred to medium containing ABA. Analysis of lipids following alkaline hydrolysis indicated that incorporation of ({sup 14}C)-palmitate into glucosylceramide of ABA-treated cells was less than 60% of control values when expressed relative to that of the total polar lipids. Incorporation into ceramides was also depressed in ABA-treated cells.

Lynch, D.V.; Joseph, R.A. (Cornell Univ., Ithaca, NY (USA))

1989-04-01

369

[Depression as chronobiological illness].  

PubMed

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

Kálmán, Janos; Kálmán, Sára

2009-06-01

370

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

371

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

372

Depression and College Students  

E-print Network

in the previous year.2 Suicide is the third leading cause of death for teens and young adults ages 15 to 24. Depression is also a major risk factor for suicide.6 Better diagnosis and treatment of depression can help reduce suicide rates among college students. In the Fall 2009 ACHA�NCHA survey, about 6 percent

Kane, Andrew S.

373

Sweeping Points  

Microsoft Academic Search

Given a set of points in the plane, and a sweep-line as a tool, what is best way to move the points to a target point using\\u000a a sequence of sweeps? In a sweep, the sweep-line is placed at a start position somewhere in the plane, then moved orthogonally\\u000a and continuously to another parallel end position, and then lifted from

Adrian Dumitrescu; Minghui Jiang

2011-01-01

374

Satellite freeze forecast system: Executive summary  

NASA Technical Reports Server (NTRS)

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

Martsolf, J. D. (principal investigator)

1983-01-01

375

Adaptation to seasonality and the winter freeze  

PubMed Central

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

Preston, Jill C.; Sandve, Simen R.

2013-01-01

376

Hot water can freeze faster than cold?!?  

E-print Network

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

Monwhea Jeng

2005-12-29

377

GPR utilization in artificial freezing engineering  

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

378

Drying a tuberculosis vaccine without freezing.  

PubMed

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

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

2007-02-20

379

Freezing Stress Response in Woody Tissues Observed Using Low-Temperature Scanning Electron Microscopy and Freeze Substitution Techniques 1  

PubMed Central

The objective of the current research was to examine the response of woody plant tissues to freezing stress by using scanning electron microscopy (SEM). Nonsupercooling species red osier dogwood (Cornus stolonifera Michx.), weeping willow (Salix babylonica L.), and corkscrew willow (Salix matsudana Koidz. f. tortuosa Rehd.) survived freezing stress as low as ?60°C. Cell collapse of ray parenchyma cells of these species was expected but did not occur. It was concluded that ray parenchyma cells of these species do not fit into either the supercooling or extracellular freezing classifications. Tissues from flowering dogwood (Cornus florida L.), apple (Malus domestica Borkh. cv “Starking III”), red oak (Quercus rubra L.), scarlet oak (Quercus coccinea Muench.), and red ash (Fraxinus pennsylvanica Marsh) were confirmed as supercooling species, and did not survive exposures below ?40°C. Ray parenchyma cells of these species did not collapse in response to freezing stress, as was expected. Cell collapse along the margins of voids were observed in bark of all seven species. Voids were the result of extracellular ice crystals formed in the bark during exposure to freezing stress. Tissues prepared by freeze substitution techniques were found to be adequately preserved when compared to those prepared by conventional fixation and low temperature SEM techniques. A freezing protocol for imposing freezing stress at temperatures lower than experienced naturally in the area where the study was conducted was developed that produced responses comparable to those observed in specimens collected in the field during natural freezing events. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:16668066

Malone, Stephen R.; Ashworth, Edward N.

1991-01-01

380

Freeze mortality characteristics of the mold mite Tyrophagus putrescentiae, a significant pest of stored products.  

PubMed

The mold mite Tyrophagus putrescentiae (Shrank) is a common pest of stored food products. Until recently, commodity and facility treatments have relied on acaricides and fumigants to control this mite. However, T. putrescentiae will cause infestations in areas where acaricide or fumigant use may be restricted, prohibited, or highly impractical. Because temperature is an essential factor that limits the survival of arthropod species, extreme temperatures can be exploited as an effective method of control. Making low-temperature treatments reliable requires better temperature-time mortality estimates for different stages of this mite. This was accomplished by exposing a representative culture (eggs, nymphs, and adults) of noncold-acclimated T. putrescentiae to subfreezing temperatures to determine their supercooling points (SCPs), lower lethal temperatures (LLTs) and lethal times (LTimes) at set temperatures. The results indicate that the adult and nymphal stages of T. putrescentiae are freeze intolerant; based on 95% CIs, the adult LLT90 of -22.5 degrees C is not significantly different from the SCP of -24.2 degrees C and the nymphal LLT90 of -28.7 degrees C is not significantly different from the SCP of -26.5 degrees C. The egg stage seems to be freeze tolerant, with an LLT90 of -48.1 degrees C, significantly colder by approximately 13.5 degrees C than its SCP of -35.6 degrees C. The LTime demonstrates that 90% of all mite stages of T. putrescentiae can be controlled within commodity or packaged product by freezing to -18 degrees C for 5 h. By achieving the recommended time and temperature exposures, freezing conditions can be an effective way of controlling mites and reducing chronic infestations. PMID:21882712

Eaton, Marc; Kells, Stephen A

2011-08-01

381

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 ...

382

Treatments in depression  

PubMed Central

Major depression is believed to be a multifactorial disorder involving predisposing temperament and personality traits, exposure to traumatic and stressful life events, and biological susceptibility. Depression, both unipolar and bipolar, is a “phasic” disease. Stressful life events are known to trigger depressive episodes, while their influence seems to decrease over the course of the illness. This suggests that depression is associated with progressive stress response abnormalities, possibly linked to impairments of structural plasticity and cellular resilience. It therefore appears crucial to adequately treat depression in the early stages of the illness, in order to prevent morphological and functional abnormalities. While evidence suggests that a severely depressed patient needs antidepressant drug therapy and that a non-severely depressed patient may benefit from other approaches (ie, “nonbiological”), little research has been done on the effectiveness of different treatments for depression. The assertion that the clinical efficacy of antidepressants is comparable between the classes and within the classes of those medications may be true from a statistical viewpoint, but is of limited value in practice. The antidepressant drugs may produce differences in therapeutic response and tolerability. Among the possible predictors of outcome in depression treatment, those derived from clinical assessment, neuroendocrine investigations, polysomnographic sleep parameters, genetic variables, and brain imaging techniques have been extensively studied. This article also reviews therapeutic strategies used when initial treatment fails, and describes briefly new concepts in antidepressant therapies such as the regulation of disturbances in circadian rhythms. The treatment of depressive illness does not stop with treatment of acute episodes, and has to be envisaged as a continuous therapeutic intervention, of which we are still not able to determine the optimal duration of treatment and the moment that it should be ceased. PMID:16889105

Duval, Fabrice; Lebowitz, Barry D.; Macher, Jean-Paul

2006-01-01

383

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. PMID:23175727

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

2013-01-01

384

Phase separation during freezing upon warming of aqueous solutions  

NASA Astrophysics Data System (ADS)

Using differential scanning calorimetry, we show that the addition of solute(s) to emulsified water lowers the freezing temperature to <231 K, the homogeneous nucleation temperature of pure bulk water, or even completely suppresses freezing. In the latter case, freezing upon warming occurs above TX ? 150 K and leads to a phase separation into pure ice and a freeze-concentrated solution (FCS) which crystallizes upon further warming. We also show that emulsified 20-21.5 wt. % HCl solutions and the FCS of HCl/H2O solutions transform to glass at Tg ? 127-128 K, i.e., lower than Tg ? 136 K of water. We suggest that water nanodrops adsorbed on fumed silica resemble bulk water more than water confined in nanoscaled confinement and also more than nanoscaled water domains in aqueous solution.

Bogdan, A.; Loerting, T.

2014-11-01

385

Phase separation during freezing upon warming of aqueous solutions.  

PubMed

Using differential scanning calorimetry, we show that the addition of solute(s) to emulsified water lowers the freezing temperature to <231 K, the homogeneous nucleation temperature of pure bulk water, or even completely suppresses freezing. In the latter case, freezing upon warming occurs above TX ? 150 K and leads to a phase separation into pure ice and a freeze-concentrated solution (FCS) which crystallizes upon further warming. We also show that emulsified 20-21.5 wt. % HCl solutions and the FCS of HCl/H2O solutions transform to glass at Tg ? 127-128 K, i.e., lower than Tg ? 136 K of water. We suggest that water nanodrops adsorbed on fumed silica resemble bulk water more than water confined in nanoscaled confinement and also more than nanoscaled water domains in aqueous solution. PMID:25399198

Bogdan, A; Loerting, T

2014-11-14

386

ARCTIC FOUNDATIONS, INC. FREEZE BARRIER SYSTEM - SITE TECHNOLOGY CAPSULE  

EPA Science Inventory

Arctic Foundations, Inc. (AFI), of Anchorage, Alaska has developed a freeze barrier technology designed to prevent the migration of contaminants in groundwater by completely isolating contaminant source areas until appropriate remediation techniques can be applied. With this tec...

387

ARCTIC FOUNDATIONS, INC. FREEZE BARRIER TECHNOLOGY; INNOVATIVE TECHNOLOGY EVALUATION REPORT  

EPA Science Inventory

Arctic Foundations, Inc. (AFI), of Anchorage, Alaska has developed a freeze barrier technology designed to prevent the migration of contaminants in groundwater by completely isolating contaminant source areas until appropriate remediation techniques can be applied. With this tech...

388

Condensation and freezing of droplets on superhydrophobic surfaces.  

PubMed

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

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

2014-08-01

389

The Hazards of Debt: Rollover Freezes, Incentives, and Bailouts  

E-print Network

We investigate the trade-off between incentive provision and inefficient rollover freezes for a firm financed with short-term debt. First, debt maturity that is too short-term is inefficient, even with incentive provision. ...

Cheng, Ing-Haw

390

Universality of tip singularity formation in freezing water drops.  

PubMed

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

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

2014-08-01

391

Optimal conditions for freezing CHO-S and HEK293-EBNA cell lines: influence of Me2SO, freeze density, and PEI-mediated transfection on revitalization and growth of cells, and expression of recombinant protein.  

PubMed

To avoid the time consuming, labor intensive seed-train expansion and to improve production reliability and consistency, portions of bulk cryopreserved cells from the same cultivation can be utilized as inocula or alternatively may be used to undertake transient transfections for large-scale bioreactor production. In this study, the conditions for large-scale freezing in cryobags were optimized utilizing a design of experiment approach. We showed that relatively high density of 30-40 x 10(6) cells/mL and relatively low Me(2)SO concentrations of 5-6% in the freezing media are optimal to freeze HEK293-EBNA and CHO-S cells in a controlled manner in order to achieve high viable cell recovery and growth post-thawing. The immediate transfer of freshly thawed cells into culture medium resulted in better cell growth compared to cells that were centrifuged in order to remove Me(2)SO. This was the case as long as the residual Me(2)SO did not exceed 0.2-0.3%. The best time to perform transient 25 kDa polyethylenimine-mediated transfection of pCEP4-EGFP plasmid into freshly thawed, one-step inoculated cells is after 72-96 h in culture. At this time point, the numbers of EGFP-positive cells in the freshly thawed culture mimic perfectly that of cells grown continuously. Finally, our data showed that it is possible to freeze transiently polyethyleneimine-transfected HEK293-EBNA cells and maintain growth rate and expression of recombinant protein following thawing. The optimal time point for freezing cells was 4 h after transfection. PMID:18351658

Kleman, Marika I; Oellers, Kerstin; Lullau, Elke

2008-08-01

392

Tipping Points  

Microsoft Academic Search

A climate tipping point, at least as I have used the phrase, refers to a situation in which a changing climate forcing has reached a point such that little additional forcing (or global temperature change) is needed to cause large, relatively rapid, climate change. Present examples include potential loss of all Arctic sea ice and instability of the West Antarctic

J. Hansen

2007-01-01

393

Triple point determinations of monomethylhydrazine and nitrogen tetroxide, 2.2 percent by weight nitric oxide  

NASA Technical Reports Server (NTRS)

A series of tests was performed to ascertain the triple points of monomethylhydrazine and nitrogen tetroxide. A laboratory method indicated a triple point for monomethylhydrazine, but tests in a large vacuum chamber indicated that a triple point does not occur in spacelike conditions because the mono-methylhydrazine tends to supercool. Instead, an effective freezing point (with agitation) was obtained. New experimental values for liquid monomethylhydrazine vapor pressure were determined for temperatures from 275.2 to 207.6 K. The values were used to derive vapor pressure equations. Tentative values were obtained for the effective freezing point of nitrogen tetroxide spacelike conditions.

Smith, Irwin D.; Dhooge, Patrick M.

1977-01-01

394

Successful pregnancies with directional freezing of large volume buck semen  

Microsoft Academic Search

Artificial insemination with frozen-thawed buck semen shows variable results which depend on many factors related to semen quality and the cryopreservation processing. We conducted experiments based on a new freezing method, directional freezing, of large volumes (8ml). In the first experiment semen from three Saanen bucks, ages 1–2-years-old and genetically selected for milk improvement, was frozen individually. Two to three-years-old

H. Gacitua; A. Arav

2005-01-01

395

Three keys to the radiation of angiosperms into freezing environments.  

PubMed

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

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

2014-02-01

396

Correlation estimates ethane plant's carbon-dioxide freezing pressure  

Microsoft Academic Search

This paper describes a new correlation model which allows quick calculation of the expected COâ freezing pressure in a turboexpander ethane extraction plant. It presents a program for use with the TI-58 calculator which incorporates the correlation equations. If the recommended 2,750 kPa minimum COâ freezing pressure is applied, then 73% ethane recovery is the maximum level that could safely

Trebble

1983-01-01

397

A climatological analysis of the freeze period of Texas  

E-print Network

A CLIMATOLOGICAL ANALYSIS OF THE FREEZE PERIOD OF TEKAS A Thesis by CHRISTOPHER ALAN DONAHUE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1991 Major Subject: Meteorology A CLIMATOLOGICAL ANALYSIS OF THE FREEZE PERIOD OF TEXAS A Thesis by CHRISTOPHER ALAN DONAHUE Approved as to style and content by: ohn F. Gri ths (Chair of Committee) Gerald R. North (Member) Michael T. L...

Donahue, Christopher Alan

2012-06-07

398

Freeze concentration of dairy products Phase 2. Final report  

SciTech Connect

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

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

1993-09-01

399

Tipping Points  

NASA Astrophysics Data System (ADS)

A climate tipping point, at least as I have used the phrase, refers to a situation in which a changing climate forcing has reached a point such that little additional forcing (or global temperature change) is needed to cause large, relatively rapid, climate change. Present examples include potential loss of all Arctic sea ice and instability of the West Antarctic and Greenland ice sheets. Tipping points are characterized by ready feedbacks that amplify the effect of forcings. The notion that these may be runaway feedbacks is a misconception. However, present "unrealized" global warming, due to the climate system's thermal inertia, exacerbates the difficulty of avoiding global warming tipping points. I argue that prompt efforts to slow CO2 emissions and absolutely reduce non-CO2 forcings are both essential if we are to avoid tipping points that would be disastrous for humanity and creation, the planet as civilization knows it.

Hansen, J.

2007-12-01

400

Slag and other liquid behavior on vertical surface at near-freezing temperature  

SciTech Connect

Deposition of liquid droplets from turbulent stream to vertical surface and the subsequent transient behavior of the liquid layer are analyzed for the surface temperatures near the freezing point of the liquid. General wave behavior of the equations governing the liquid layer is elucidated. The analysis is applied to the problem of slag layer accumulation on the passage walls of a magnetohydrodynamic regenerative heat exchanger using the coal combustion product as the heat source. The wave behavior predicts the emergence of an accumulation shock that leads to clogging of the passges for certain cyclic operations.

Im, K.H. (Argonne National Lab., IL); Chung, P.M.

1980-11-01

401

Liver glycogen, glucose mobilization and freezing survival in chorus frogs, Pseudacris triseriata  

Microsoft Academic Search

We compared liver glycogen stores and glucose mobilization during freezing among winters in chorus frogs, Pseudacris triseriata, where populations varied in freezing survival. We also characterized tissue glycogen levels across the annual cycle. Frogs with low liver glycogen stores mobilized low amounts of glucose during freezing, and these were correlated with population variation in freezing survival. Moreover, liver glycogen stores

Jennifer L. Jenkins; David L. Swanson

2005-01-01

402

Application of the SAFES (systematic approach to food engineering systems) methodology to strawberry freezing process  

Microsoft Academic Search

SAFES methodology has been applied in strawberry freezing process using data from references. Three cases of freezing have been studied. All of them start from the refrigerated temperature (Tc) and there is a first stage of cooling until the initial freezing temperature (Tm) is reached. However, the changes of components depend on the temperature reached and the rate of freezing.

M. L. Castelló; P. J. Fito; A. Argüelles

2007-01-01

403

Reptile freeze tolerance: Metabolism and gene expression q Kenneth B. Storey *  

E-print Network

to temperatures below 0 °C cannot be avoided, either freeze avoidance (supercooling) or freeze toleranceReview Reptile freeze tolerance: Metabolism and gene expression q Kenneth B. Storey * Institute reptile species display ecologically relevant freeze tolerance, sur- viving for extended times with 50

Storey, Kenneth B.

404

Xylem cavitation caused by drought and freezing stress in four co-occurring Juniperus species  

E-print Network

Xylem cavitation caused by drought and freezing stress in four co-occurring Juniperus species induced by drought but in many cases, not by freezing. Rarely have vulnerability to drought and freezing and distribution of plants in many regions of the world. We studied vulnerability to drought- and freezing- induced

Jackson, Robert B.

405

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

NASA Technical Reports Server (NTRS)

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

Karel, M.; Flink, J. M.

1978-01-01

406

Cryo-fixation by self-pressurized rapid freezing.  

PubMed

High-pressure freeze fixation is the method of choice to arrest instantly all dynamic and physiological processes inside cells, tissues, and small organisms. Embedded in vitreous ice, such samples can be further processed by freeze substitution or directly analyzed in their fully hydrated state by cryo-electron microscopy of vitreous sections (CEMOVIS) to explore cellular ultrastructure as close as possible to the native state. Here, we describe the procedure of self-pressurized rapid freezing as fast, easy-to-use, and low-cost freeze fixation method, avoiding the usage of a high-pressure freezing (HPF) apparatus. Cells or small organisms are placed in capillary metal tubes, which are tightly closed and plunged directly into liquid ethane cooled by liquid nitrogen. In parts of the tube, crystalline ice is formed and builds up pressure sufficient for the liquid-glass transition of the remaining specimen. The quality of samples is equivalent to preparations by conventional HPF apparatus, allowing for high-resolution cryo-EM applications or for freeze substitution and plastic embedding. PMID:24357364

Grabenbauer, Markus; Han, Hong-Mei; Huebinger, Jan

2014-01-01

407

Viability of freeze dried microencapsulated human retinal pigment epithelial cells.  

PubMed

Encapsulated human retinal pigment epithelial cell line ARPE-19 has been successfully used in experimental cell therapy of retinal degenerations and Parkinson's disease, but the long-term storage of encapsulated cells is still an unresolved question. Reconstitution of viable encapsulated cells from dry form would benefit the development of cell therapy products. We freeze dried and reconstituted microencapsulated ARPE19 and ARPE19-SEAP cells. Cross-linked alginate matrix with polycation (poly-l-lysine, cationic starch) coating was used for microencapsulation. Cell viability was assessed with fluorescence microscopy and oxygen consumption of the cells. Freeze dried and reconstituted cell microcapsules were imaged using scanning electron microscopy (SEM) and environmental scanning electron microscopy (ESEM). We show partial viability of microencapsulated cells after freeze-drying. Unlike poly-l-lysine (PLL) coating, cationic starch supported microcapsule shape and cell viability during freeze-drying. Trehalose pre-treatment augmented cell viability. Likewise, some lyoprotectants (trehalose, glycerol) enabled preservation of cell viability. Upon reconstitution the freeze dried cell microcapsules rapidly regained their original spherical shape. This proof-of-concept study demonstrates that microencapsulated cells can retain their viability during freeze-drying. Therefore, this approach can be further optimized for the benefit of cell therapy product development. PMID:22820032

Wikström, Jonna; Elomaa, Matti; Nevala, Laura; Räikkönen, Johanna; Heljo, Petteri; Urtti, Arto; Yliperttula, Marjo

2012-09-29

408

Low-temperature brewing by freeze-dried immobilized cells.  

PubMed

We propose a novel biocatalyst in brewing. A cryotolerant strain of Saccharomyces cerevisiae was immobilized on delignified cellulosic material followed by freeze-drying of the immobilized cells without the use of any cryoprotectant. The freeze-dried immobilized biocatalyst was used in repeated-batch fermentation of wort and showed reduced fermentation time and increased productivities as compared with free freeze-dried cells (FFDCs). It also demonstrated suitability for low-temperature brewing (5 and 0 degrees C). The fermentation time in repeated-batch fermentations at 15 degrees C was 1.5-2 d for a period of 13 mo, showing a high operational stability of the system. At 0 degrees C the freeze-dried immobilized biocatalyst showed a 2- to 3.5-fold decrease in fermentation time in comparison with FFDCs. Polyphenol contents, bitterness, and diacetyl concentration were lower in beers produced by freeze-dried immobilized cells as compared with FFDCs. At 0 degrees C polyphenols were 40% lower than at 15 degrees C. Higher alcohols were reduced and ethyl acetate increased in comparison with FFDCs. Amyl alcohols at 0 degrees C were lower than half of their content at 15 degrees C, while ethyl acetate was 31 mg/L at 0 degrees C and 18 mg/L at 15 degrees C. These data justify the improved aroma and taste of beers produced by freeze-dried immobilized biocatalyst mainly at low temperatures. PMID:11996222

Bekatorou, Argyro; Soupioni, Magda J; Koutinas, Athanasios A; Kanellaki, Maria E

2002-02-01

409

Freeze concentration of dairy products, Phase 1: Final report  

SciTech Connect

The objective of this study was to explore freeze concentration as a process to replace thermal evaporation in the dairy industry. The goals of the study were to save energy by converting concentration processes to an efficient, electrically powered, refrigeration system, and to create higher quality and innovative products that might bring new life to a nature dairy market. A small freeze concentration pilot plant was used to concentrate products for quality comparisons, for physical and chemical analytical determinations, and to discover any equipment/product attributes or limitations. Data was correlated to compare operating economics of freeze concentrations superior to the fresh feedstock in sensory and functionality tests upon reconstitution. Laboratory testing showed equal or superior quality in resulting spray dried powders from freeze concentrates. Freeze concentration was shown to be economically competitive with thermal processes and second generation freezing technology is projected to produce a substantially less expensive product and offer other advantages over current thermally produced goods. 31 figs., 14 tabs.

Luksas, A.; Ahmed, S.; Johnson, T.A.

1989-03-01

410

Freeze avoidance: a dehydrating moss gathers no ice.  

PubMed

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

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

2010-10-01

411

Freezing of barley studied by infrared video thermography.  

PubMed

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

Pearce, R S; Fuller, M P

2001-01-01

412

Freezing of Barley Studied by Infrared Video Thermography1  

PubMed Central

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

Pearce, Roger S.; Fuller, Michael P.

2001-01-01

413

Relationship of Beck Depression Inventory factors to depression among adolescents  

Microsoft Academic Search

Beck Depression Inventory (BDI) scores of 328 adolescents referred to a depression clinic were factor analyzed to test the discriminant validity of each factor. Three of the four factors (Negative Self Attitude, Performance Difficulty, and Somatic Symptoms) discriminated depressed adolescents from those with a behavior disorder or no diagnosis; the Negative Self Attitude and Performance Difficulty factors also discriminated depressed

David S Bennett; Paul J Ambrosini; Michael Bianchi; Diana Barnett; Claudia Metz; Harris Rabinovich

1997-01-01

414

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. PMID:19350435

Barnard, Amy

2009-01-01

415

Imaging the Endothelial Glycocalyx In Vitro by Rapid Freezing/Freeze Substitution Transmission Electron Microscopy  

PubMed Central

Objective Recent publications questioned the validity of endothelial cell (EC) culture studies of glycocalyx (GCX) function, due to findings that GCX in vitro may be substantially thinner than in vivo. The assessment of thickness differences is complicated by GCX collapse during dehydration for traditional electron microscopy. We measured in vitro GCX thickness using rapid freezing/freeze substitution transmission electron microscopy (RF/FS-TEM), taking advantage of high spatial resolution provided by TEM and the capability to stably preserve the GCX in its hydrated configuration by RF/FS. Methods and Results Bovine aortic and rat fat pad endothelial cells (BAEC and RFPEC) were subjected to conventional- or RF/FS-TEM. Conventionally preserved BAEC GCX was ~0.040 ?m in thickness. RF/FS-TEM revealed impressively thick BAEC GCX of ~11 ?m and RFPEC GCX of ~5 ?m. RF/FS-TEM also discerned GCX structure and thickness variations due to heparinase III enzyme treatment and extracellular protein removal, respectively. Immunoconfocal studies confirmed that the in vitro GCX is several microns thick and is comprised of extensive and well integrated heparan sulfate, hyaluronic acid, and protein layers. Conclusions New observations by RF/FS-TEM reveal substantial GCX layers on cultured EC, supporting their continued use for fundamental studies of GCX and its function in the vasculature. PMID:21474821

Ebong, Eno E; Macaluso, Frank P; Spray, David C; Tarbell, John M

2011-01-01

416

Inhibition, Executive Function, and Freezing of Gait  

PubMed Central

Background Studies suggest that freezing of gait (FoG) in people with Parkinson’s disease (PD) is associated with declines in executive function (EF). However, EF is multi-faceted, including three dissociable components: inhibiting prepotent responses, switching between task sets, and updating working memory. Objective This study investigated which aspect of EF is most strongly associated with FoG in PD. Method Three groups were studied: adults with PD (with and without FoG) and age-matched, healthy adults. All participants completed a battery of cognitive tasks previously shown to discriminate among the three EF components. Participants also completed a turning-in-place task that was scored for FoG by neurologists blind to subjects’ self-reported FoG. Results Compared to both other groups, participants with FoG showed significant performance deficits in tasks associated with inhibitory control, even after accounting for differences in disease severity, but no significant deficits in task-switching or updating working memory. Surprisingly, the strongest effect was an intermittent tendency of participants with FoG to hesitate, and thus miss the response window, on go trials in the Go-Nogo task. The FoG group also made slower responses in the conflict condition of the Stroop task. Physician-rated FoG scores were correlated both with failures to respond on go trials and with failures to inhibit responses on nogo trials in the Go-Nogo task. Conclusion These results suggest that FoG is associated with a specific inability to appropriately engage and release inhibition, rather than with a general executive deficit. PMID:24496099

Cohen, Rajal G.; Klein, Krystal A.; Nomura, Mariko; Fleming, Michael; Mancini, Martina; Giladi, Nir; Nutt, John G.; Horak, Fay B.

2014-01-01

417

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. PMID:20185745

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

2010-01-01

418

Management of Postpartum Depression  

PubMed Central

Postpartum depression, now termed peripartum depression by the DSM-V, is one of the most common complications in the postpartum period and has potentially significant negative consequences for mothers and their families. This article highlights common clinical challenges in the treatment of peripartum depression and reviews the evidence for currently available treatment options. Psychotherapy is the first-line treatment options for women with mild-to-moderate peripartum depression. Antidepressant medication in combination with therapy is recommended for women with moderate-to-severe depression. While pooled case reports and small controlled studies have demonstrated undetectable infant serum levels and no short-term adverse events in infants of mothers breastfeeding while taking sertraline (Zoloft) and paroxetine (Paxil), further research is needed including larger samples and long-term follow-up of infants exposed to antidepressants via breastfeeding with control for maternal depression. Pharmacological treatment recommendations in women who are lactating must include discussion with the patient regarding the benefits of breastfeeding, risks of antidepressant use during lactation and risks of untreated illness. There is a growing evidence base for non-pharmacological interventions including repetitive Transcranial Magnetic Stimulation (rTMS) which may offer an attractive option for women who wish to continue to breastfeed and are concerned about exposure of medication to their infant. Among severe cases of peripartum depression with psychosis referral to a psychiatrist or psychiatric APRN is warranted. Suicidal or homicidal ideation with a desire, intent or plan to harm oneself or anyone one else, including the infant, is a psychiatric emergency, and an evaluation by a mental health professional should be conducted immediately. Peripartum depression treatment research is limited by small samples sizes and few controlled studies. Much work is still needed to better understand which treatments women prefer and are the most effective in ameliorating the symptoms and disease burden associated with peripartum depression. PMID:24131708

Guille, Constance; Newman, Roger; Fryml, Leah D.; Lifton, Clay K.; Epperson, C. Neill

2013-01-01

419

[Chronic pain and depression].  

PubMed

Chronic pain and depression are frequently associated. Links between them are numerous and well documented. It is known for example that depression is associated with a greater number and higher intensity of pain symptoms. Similarly the presence of pain complicates the diagnostic evaluation and aggravates the prognosis of depression. The question of the causality link has no clear answer. Taking care of these patients implies to acknowledge the different aspects of their suffering in a holistic bio-psycho-social model. Treatment or medication, for instance antidepressants, should be a post-scriptum to the construction of a therapeutic relationship. PMID:19626761

Rentsch, D; Piguet, V; Cedraschi, C; Desmeules, J; Luthy, C; Andreoli, A; Allaz, A F

2009-06-17

420

Depression in adolescence.  

PubMed

Depressive illness in adolescence is common. It can also be life-threatening, disabling, chronic, recurrent and occasionally it can progress to a bipolar disorder. Regrettably, the diagnosis is often missed. The features of depression in this age group are generally similar to those in adults but there are potential differences. Engaging the patient and assessing safety are key components of the first interview. Treatment options for the GP include psychological and pharmacological approaches. The evidence for the effectiveness of antidepressants is not as compelling as in depressed adults. When antidepressants are indicated, the newer antidepressants are preferable. Knowing when to refer to specialist agencies is an important aspect of management. PMID:8936739

Walter, G

1996-10-01

421

Maternal depressive symptoms and weight-related parenting behaviors.  

PubMed

This study examined associations between mothers' depressive symptoms and parenting behaviors related to children's nutrition and physical activity. Data from the Early Childhood Longitudinal Study-Birth Cohort, a nationally representative study of children from infancy through kindergarten entry. Contemporaneous and lagged associations between maternal depressive symptoms and mothers' parenting behaviors were tested, controlling for background characteristics. The mediating effect of use of a physician's office or clinic as a source for routine care was tested. At each wave, between 18 and 20 % of mothers were considered as having moderate or severe depressive symptoms. These mothers were 1.3 percentage points more likely to put their infants to bed with a bottle, 2.6 percentage points less likely to have rules about the foods their children eat, and their children were 3.0 percentage points less likely to be in bed by 9:00 p.m. than mothers lacking depressive symptoms. These mothers also reported that their families ate dinner together fewer nights per week, and their children watched more television per day, than non-depressed mothers. The use of a physician's office or clinic partially mediated associations between maternal depressive symptoms and whether infants went to bed with a bottle. Interventions that identify maternal depression early may be useful in promoting healthy parenting behaviors and weight outcomes among young children. PMID:24077962

Morrissey, Taryn W

2014-08-01

422

Optimization of Intensification of Freeze-Drying Rate of Banana: Combined Applications of IR Radiation and Cryogenic Freezing  

Microsoft Academic Search

A programmed experimental study on infrared (IR) aided freeze-drying of cryogenically (LN2) frozen heat sensitive material viz. banana (Musa acuminata) rendered faster moisture separation rate compared to the conventionally frozen samples. Response surface methodology (RSM) could determine the simultaneous optimal freeze-drying conditions of 59.78°C IR temperature, 10 mm sample thickness and 5 h drying time corresponding to minimum moisture content of 4.11%,

M. Bera; R. Chakraborty; P. Bhattacharya

2012-01-01

423

Depression, Pain, and Pain Behavior.  

ERIC Educational Resources Information Center

Examined the degree to which depression predicted pain and pain behavior. The Beck Depression Inventory was administered to 207 low back pain patients. Depression and physical findings were the most important predictors of pain and pain behavior. Depression proved significant even after controlling for important demographic and medical status…

Keefe, Francis J.; And Others

1986-01-01

424

Depression, Dementia, and Social Supports.  

ERIC Educational Resources Information Center

Reviews recent literature on the relationships among dementia, depression, and social support, emphasizing the diagnostic differentiation of dementia and depression, and the role of these three entities in elderly with cognitive impairment. Discusses dementia-like symptoms arising in depression and the coexistence of dementia and depression.…

Esser, Sally R.; Vitaliano, Peter P.

1988-01-01

425

HIF-1? involvement in low temperature and anoxia survival by a freeze tolerant insect  

Microsoft Academic Search

Winter survival for many insect species relies on the ability to endure the freezing of extracellular body fluids. Because\\u000a freezing impedes oxygen delivery to tissues, one component of natural freeze tolerance is a well-developed anoxia\\/ischemia\\u000a resistance. The present study explores the responses of the hypoxia-inducible factor-1? (HIF-1?) to cold, freezing and anoxia\\u000a exposures in the freeze tolerant goldenrod gall fly

Pier Morin; David C. McMullen; Kenneth B. Storey

2005-01-01

426

Time course for cryoprotectant synthesis in the freeze-tolerant chorus frog, Pseudacris triseriata  

Microsoft Academic Search

Increases in liver glycogen phosphorylase activity, along with inhibition of glycogen synthetase and phosphofructokinase-1, are associated with elevated cryoprotectant (glucose) levels during freezing in some freeze-tolerant anurans. In contrast, freeze-tolerant chorus frogs, Pseudacris triseriata, accumulate glucose during freezing but exhibit no increase in phosphorylase activity following 24-h freezing bouts. In the present study, chorus frogs were frozen for 5- and

Joshua R Edwards; Karen L Koster; David L Swanson

2000-01-01

427

Repeated freeze–thaw cycles induce embolism in drought stressed conifers (Norway spruce, stone pine)  

Microsoft Academic Search

Freezing and thawing lead to xylem embolism when gas bubbles caused by ice formation expand during the thaw process. However, previous experimental studies indicated that conifers are resistant to freezing-induced embolism, unless xylem pressure becomes very negative during the freezing. In this study, we show that conifers experienced freezing-induced embolism when exposed to repeated freeze–thaw cycles and simultaneously to drought.

Stefan Mayr; Andreas Gruber; Helmut Bauer

2003-01-01

428

Does Platelet-Rich Plasma Freeze-Thawing Influence Growth Factor Release and Their Effects on Chondrocytes and Synoviocytes?  

PubMed Central

PRP cryopreservation remains a controversial point. Our purpose was to investigate the effect of freezing/thawing on PRP molecule release, and its effects on the metabolism of chondrocytes and synoviocytes. PRP was prepared from 10 volunteers, and a half volume underwent one freezing/thawing cycle. IL-1?, HGF, PDGF AB/BB, TGF-?1, and VEGF were assayed 1 hour and 7 days after activation. Culture media of chondrocytes and synoviocytes were supplemented with fresh or frozen PRP, and, at 7 days, proliferation, gene expression, and secreted proteins levels were evaluated. Results showed that in the freeze-thawed PRP the immediate and delayed molecule releases were similar or slightly lower than those in fresh PRP. TGF-?1 and PDGF AB/BB concentrations were significantly reduced after freezing both at 1 hour and at 7 days, whereas HGF concentration was significantly lower in frozen PRP at 7 days. In fresh PRP IL-1? and HGF concentrations underwent a significant further increase after 7 days. Similar gene expression was found in chondrocytes cultured with both PRPs, whereas in synoviocytes HGF gene expression was higher in frozen PRP. PRP cryopreservation is a safe procedure, which sufficiently preserves PRP quality and its ability to induce proliferation and the production of ECM components in chondrocytes and synoviocytes. PMID:25136613

Cavallo, Carola; Cenacchi, Annarita; Facchini, Andrea; Grigolo, Brunella; Kon, Elizaveta; Mariani, Erminia; Pratelli, Loredana; Marcacci, Maurilio

2014-01-01

429

A nonprotein thermal hysteresis-producing xylomannan antifreeze in the freeze-tolerant Alaskan beetle Upis ceramboides  

PubMed Central

Thermal hysteresis (TH), a difference between the melting and freezing points of a solution that is indicative of the presence of large-molecular-mass antifreezes (e.g., antifreeze proteins), has been described in animals, plants, bacteria, and fungi. Although all previously described TH-producing biomolecules are proteins, most thermal hysteresis factors (THFs) have not yet been structurally characterized, and none have been characterized from a freeze-tolerant animal. We isolated a highly active THF from the freeze-tolerant beetle, Upis ceramboides, by means of ice affinity. Amino acid chromatographic analysis, polyacrylamide gel electrophoresis, UV-Vis spectrophotometry, and NMR spectroscopy indicated that the THF contained little or no protein, yet it produced 3.7 ± 0.3 °C of TH at 5 mg/ml, comparable to that of the most active insect antifreeze proteins. Compositional and structural analyses indicated that this antifreeze contains a ?-mannopyranosyl-(1?4) ?-xylopyranose backbone and a fatty acid component, although the lipid may not be covalently linked to the saccharide. Consistent with the proposed structure, treatment with endo-?-(1?4)xylanase ablated TH activity. This xylomannan is the first TH-producing antifreeze isolated from a freeze-tolerant animal and the first in a new class of highly active THFs that contain little or no protein. PMID:19934038

Walters, Kent R.; Serianni, Anthony S.; Sformo, Todd; Barnes, Brian M.; Duman, John G.

2009-01-01

430

Does platelet-rich plasma freeze-thawing influence growth factor release and their effects on chondrocytes and synoviocytes?  

PubMed

PRP cryopreservation remains a controversial point. Our purpose was to investigate the effect of freezing/thawing on PRP molecule release, and its effects on the metabolism of chondrocytes and synoviocytes. PRP was prepared from 10 volunteers, and a half volume underwent one freezing/thawing cycle. IL-1?, HGF, PDGF AB/BB, TGF-?1, and VEGF were assayed 1 hour and 7 days after activation. Culture media of chondrocytes and synoviocytes were supplemented with fresh or frozen PRP, and, at 7 days, proliferation, gene expression, and secreted proteins levels were evaluated. Results showed that in the freeze-thawed PRP the immediate and delayed molecule releases were similar or slightly lower than those in fresh PRP. TGF-?1 and PDGF AB/BB concentrations were significantly reduced after freezing both at 1 hour and at 7 days, whereas HGF concentration was significantly lower in frozen PRP at 7 days. In fresh PRP IL-1? and HGF concentrations underwent a significant further increase after 7 days. Similar gene expression was found in chondrocytes cultured with both PRPs, whereas in synoviocytes HGF gene expression was higher in frozen PRP. PRP cryopreservation is a safe procedure, which sufficiently preserves PRP quality and its ability to induce proliferation and the production of ECM components in chondrocytes and synoviocytes. PMID:25136613

Roffi, Alice; Filardo, Giuseppe; Assirelli, Elisa; Cavallo, Carola; Cenacchi, Annarita; Facchini, Andrea; Grigolo, Brunella; Kon, Elizaveta; Mariani, Erminia; Pratelli, Loredana; Pulsatelli, Lia; Marcacci, Maurilio

2014-01-01

431

Freeze resistance in rainbow smelt (Osmerus mordax): seasonal pattern of glycerol and antifreeze protein levels and liver enzyme activity associated with glycerol production.  

PubMed

Rainbow smelt (Osmerus mordax) inhabit inshore waters along the North American Atlantic coast. During the winter, these waters are frequently ice covered and can reach temperatures as low as -1.9 degrees C. To prevent freezing, smelt accumulate high levels of glycerol, which lower the freezing point via colligative means, and antifreeze proteins (AFP). The up-regulation of the antifreeze response (both glycerol and AFP) occurs in early fall, when water temperatures are 5 degrees -6 degrees C. The accumulation of glycerol appears to be the main mechanism of freeze resistance in smelt because it contributes more to the lowering of the body's freezing point than the activity of the AFP (0.5 degrees C vs. 0.25 degrees C for glycerol and AFP, respectively) at a water temperature of -1.5 degrees C. Moreover, AFP in smelt appears to be a safeguard mechanism to prevent freezing when glycerol levels are low. Significant increases in activities of the liver enzymes glycerol 3-phosphate dehydrogenase (GPDH), alanine aminotransferase (AlaAT), and phosphoenolpyruvate carboxykinase (PEPCK) during the initiation of glycerol production and significant correlations between enzyme activities and plasma glycerol levels suggest that these enzymes are closely associated with the synthesis and maintenance of elevated glycerol levels for use as an antifreeze. These findings add further support to the concept that carbon for glycerol is derived from amino acids. PMID:15286915

Lewis, Johanne M; Ewart, K Vanya; Driedzic, William R

2004-01-01

432

Neuroinflammation, Neurodegeneration and Depression  

PubMed Central

Neurodegeneration and depression are two common co-morbid conditions, particularly within the aging population. Research has linked neuroinflammation as a major contributing factor to both of these diseases. The key to neuroinflammation effects on neurodegeneration and depression appears to lie within the dysregulation of the control and release of pro- and anti-inflammatory cytokines. This can come from an internal or external insult to the system, or from changes in the individual due to aging that culminate in immune dysregulation. The need to reduce neuroinflammation has led to extensive research into neuroprotectants. We discuss the efficacy found with nicotine, alcohol, resveratrol, curcumin, and ketamine. Our main focus will be on what research is telling us about the connections between neuroinflammation, neurodegeneration, and depression, and the hope that neuroprotectants research is giving people suffering from neurodegeneration and depression stemming from neuroinflammation. We will conclude by making suggestions for future research in this area. PMID:22895696

Hurley, Laura L.; Tizabi, Yousef

2013-01-01

433

Multimorbidity and depression treatment  

Microsoft Academic Search

ObjectivesWe compare treatment for depression among individuals with multiple chronic physical conditions to those with single chronic physical condition, after controlling for demographic, socioeconomic, access to care and the number of outpatient visits.

Ami Vyas; Usha Sambamoorthi

2011-01-01

434

Multiple sclerosis and depression.  

PubMed

Clinically significant depression can affect up to 50% of patients with multiple sclerosis over the course of their lifetime. It is associated with an increased morbidity and mortality and is regarded by patients as one of the main determinants of their quality of life. This review summarizes current perspectives relating to diagnosis, the utility of self report screening questionnaires, warning signs of suicidal intent and the biological and psychosocial variables implicated in mood change. In particular, the association between depression and structural brain abnormalities, including those derived from diffusion tensor imaging, is highlighted. Depression is treatable, as the results from randomized controlled trials of antidepressant medication, cognitive behavior therapy and mindfulness therapy, reveal. These positive findings are offset by data showing that depression in a neurological setting is often overlooked and under treated. PMID:22058085

Feinstein, Anthony

2011-11-01

435

Overcoming and Managing Depression  

ERIC Educational Resources Information Center

This article describes a workshop designed to dispel the myth of learned helplessness and facilitate people's reintegrating their previously denied power. The approaches used to help students deal with depression are described in detail. (EJT)

Ribner, Neil; Ginn, Roger

1975-01-01

436

Learning about depression  

MedlinePLUS

Fava M, Cassano P. Mood disorders: Major depressive disorder and dysthymic disorder. In: Stern TA, Rosenbaum JF, Fava M, Biederman J, Rauch SL, eds. Massachusetts General Hospital Comprehensive Clinical Psychiatry . 1st ed. ...

437

The psychoneuroimmunology of depression.  

PubMed

Chronic stress, by initiating changes in the hypothalamic-pituitary-adrenal (HPA) axis and the immune system, acts as a trigger for anxiety and depression. There is experimental and clinical evidence that the rise in the concentration of pro-inflammatory cytokines and glucocorticoids, which occurs in a chronically stressful situation and also in depression, contribute to the behavioural changes associated with depression. A defect in serotonergic function is associated with these hormonal and immune changes. Neurodegenerative changes in the hippocampus, prefrontal cortex and amygdalae are the frequent outcome of the changes in the HPA axis and the immune system. Such changes may provide evidence for the link between chronic depression and dementia in later life. PMID:19212943

Leonard, Brian E; Myint, Ayemu

2009-04-01

438

Depression in adolescence.  

PubMed

Major depressive disorder is a common problem for adolescents. It has a wide array of symptoms affecting somatic, cognitive, affective, and social processes. Academic failure, poor peer relationships, behavioral problems, conflict with parents and other authority figures, and substance abuse are some of the consequences of major depressive disorder in this age group. Effective treatments include nontricyclic antidepressants and coping skills training. The nurse is key to depression detection and suicide prevention, especially in primary care settings. Through psychoeducation, nurses can promote recovery from depression by encouraging a healthy lifestyle, enhancing social skills, and assisting the adolescent to identify and use sources of social support. These measures can prevent premature death and promote long-term well-being of the adolescent. PMID:12685676

Hauenstein, Emily J

2003-01-01

439

Escitalopram (Lexapro) for depression.  

PubMed

Escitalopram (Lexapro) is the active s-enantiomer of the selective serotonin reuptake inhibitor (SSRI), citalopram (Celexa). It is labeled for the treatment of major depressive disorder. PMID:14677669

Masilamani, Santhi; Ruppelt, Sara C

2003-12-01

440

Deposition nucleation viewed as homogeneous or immersion freezing in pores and cavities  

NASA Astrophysics Data System (ADS)

Heterogeneous ice nucleation is an important mechanism for the glaciation of mixed phase clouds and may also be relevant for cloud formation and dehydration at the cirrus cloud level. It is thought to proceed through different mechanisms, namely contact, condensation, immersion and deposition nucleation. Supposedly, deposition nucleation is the only pathway which does not involve liquid water but occurs by direct water vapor deposition on a surface. This study challenges this classical view by putting forward the hypothesis that what is called deposition nucleation is in fact homogeneous or immersion nucleation occurring in pores and cavities that may form between aggregated primary particles and fill with water at relative humidity RHw < 100% because of the inverse Kelvin effect. Evidence for this hypothesis of pore condensation and freezing (PCF) originates from a number of only loosely connected scientific areas. The prime example for PCF is ice nucleation in clay minerals and mineral dusts, for which the data base is best. Studies on freezing in confinement carried out on mesoporous silica materials such as SBA-15, SBA-16, MCM-41, zeolites and KIT have shown that homogeneous ice nucleation occurs abruptly at T=230-235 K in pores with diameters (D) of 3.5-4 nm or larger but only gradually at T=210-230 K in pores with D=2.5-3.5 nm. Melting temperatures in pores are depressed by an amount that can be described by the Gibbs-Thomson equation. Water adsorption isotherms of MCM-41 show that pores with D=3.5-4 nm fill with water at RHw = 56-60% in accordance with an inverse Kelvin effect. Water in such pores should freeze homogeneously for T < 235 K even before relative humidity with respect to ice (RHi) reaches ice saturation. Ice crystal growth by water vapor deposition from the gas phase is therefore expected to set in as soon as RHw > 100%. Pores with D > 7.5 nm fill with water at RHi > 100% for T < 235 K and are likely to freeze homogeneously as soon as they are filled with water. Water in pores can freeze in immersion mode at T > 235 K if the pore walls contain an active site. Pore analysis of clay minerals shows that kaolinites exhibit pore structures with pore diameters of 20-50 nm. The mesoporosity of illites and montmorillonites is characterized by pores with T = 2-5 nm. The number and size of pores is distinctly increased in acid treated montmorillonites like K10. Many clay minerals and mineral dusts show a strong increase in ice nucleation efficiency when temperature is decreased below 235 K. Such an increase is difficult to explain when ice nucleation is supposed to occur by a deposition mechanism, but evident when assuming freezing in pores, because for homogeneous ice nucleation only small pore volumes are needed, while heterogeneous ice nucleation requires larger pore structures to contain at least one active site for immersion nucleation. Together, these pieces of evidence strongly suggest that ice nucleation within pores should be the prevailing freezing mechanism of clay minerals for RHw below water saturation. Extending the analysis to other types of ice nuclei shows that freezing in pores and cracks is probably the prevailing ice nucleation mechanism for glassy and volcanic ash aerosols at RHw below water saturation. Freezing of water in carbon nanotubes might be of significance for ice nucleation by soot aerosols. No case could be identified that gives clear evidence of ice nucleation by water vapor deposition on a solid surface. Inspection of ice nuclei with a close lattice match to ice, such as silver iodide or SnomaxTM, show that for high ice nucleation efficiency below water saturation the presence of impurities or cracks on the surface may be essential. Soluble impurities promote the formation of a liquid phase below water saturation in patches on the surface or as a complete surface layer that offers an environment for immersion freezing. If porous aerosol particles come in contact with semivolatile vapors, these will condense preferentially in pores before a coating on

Marcolli, C.

2013-06-01

441

Freeze-thaw cycles enhance decellularization of large tendons.  

PubMed

The use of decellularized tendon tissue as a scaffold for tendon tissue engineering provides great opportunities for future clinical and current research applications. The aim of this study was to assess the effect of repetitive freeze-thaw cycles and two different detergents, t-octyl-phenoxypolyethoxyethanol (Triton X-100) and sodium dodecyl sulfate (SDS), on decellularization effectiveness and cytocompatibility in large tendons. Freshly collected equine superficial and deep digital flexor tendons were subjected to decellularization according to four different protocols (1 and 2: freeze-thaw cycles combined with either Triton X-100 or SDS; 3 and 4: Triton X-100 or SDS). Decellularization effectiveness was assessed based on the reduction of vital cell counts, histologically visible nuclei, and DNA content. Transmission electron microscopy was performed to evaluate cellular and extracellular matrix integrity. Further, cytocompatibility of scaffolds that had been decellularized according to the protocols including freeze-thaw cycles (protocols 1 and 2) was assessed by seeding the scaffolds with superparamagnetic iron oxide labeled mesenchymal stromal cells and monitoring the cells histologically and by magnetic resonance imaging for two weeks. Decellularization was significantly more effective when using the protocols including freeze-thaw cycles, leaving only roughly 1% residual nuclei and 20% residual DNA, whereas samples that had not undergone additional freeze-thaw cycles contained roughly 20% residual nuclei and 40% residual DNA. No morphological extracellular matrix alterations due to decellularization could be observed. Scaffolds prepared by both protocols including freeze-thaw cycles were cytocompatible, but the cell distribution into the scaffold tended to be better in scaffolds that had been decellularized using freeze-thaw cycles combined with Triton X-100 instead of SDS. PMID:23879725

Burk, Janina; Erbe, Ina; Berner, Dagmar; Kacza, Johannes; Kasper, Cornelia; Pfeiffer, Bastian; Winter, Karsten; Brehm, Walter

2014-04-01

442

Freeze-Thaw Cycles Enhance Decellularization of Large Tendons  

PubMed Central

The use of decellularized tendon tissue as a scaffold for tendon tissue engineering provides great opportunities for future clinical and current research applications. The aim of this study was to assess the effect of repetitive freeze-thaw cycles and two different detergents, t-octyl-phenoxypolyethoxyethanol (Triton X-100) and sodium dodecyl sulfate (SDS), on decellularization effectiveness and cytocompatibility in large tendons. Freshly collected equine superficial and deep digital flexor tendons were subjected to decellularization according to four different protocols (1 and 2: freeze-thaw cycles combined with either Triton X-100 or SDS; 3 and 4: Triton X-100 or SDS). Decellularization effectiveness was assessed based on the reduction of vital cell counts, histologically visible nuclei, and DNA content. Transmission electron microscopy was performed to evaluate cellular and extracellular matrix integrity. Further, cytocompatibility of scaffolds that had been decellularized according to the protocols including freeze-thaw cycles (protocols 1 and 2) was assessed by seeding the scaffolds with superparamagnetic iron oxide labeled mesenchymal stromal cells and monitoring the cells histologically and by magnetic resonance imaging for two weeks. Decellularization was significantly more effective when using the protocols including freeze-thaw cycles, leaving only roughly 1% residual nuclei and 20% residual DNA, whereas samples that had not undergone additional freeze-thaw cycles contained roughly 20% residual nuclei and 40% residual DNA. No morphological extracellular matrix alterations due to decellularization could be observed. Scaffolds prepared by both protocols including freeze-thaw cycles were cytocompatible, but the cell distribution into the scaffold tended to be better in scaffolds that had been decellularized using freeze-thaw cycles combined with Triton X-100 instead of SDS. PMID:23879725

Erbe, Ina; Berner, Dagmar; Kacza, Johannes; Kasper, Cornelia; Pfeiffer, Bastian; Winter, Karsten; Brehm, Walter

2014-01-01

443

Does Anxiety Cause Freezing of Gait in Parkinson's Disease?  

PubMed Central

Individuals with Parkinson's disease (PD) commonly experience freezing of gait under time constraints, in narrow spaces, and in the dark. One commonality between these different situations is that they may all provoke anxiety, yet anxiety has never been directly examined as a cause of FOG. In this study, virtual reality was used to induce anxiety and evaluate whether it directly causes FOG. Fourteen patients with PD and freezing of gait (Freezers) and 17 PD without freezing of gait (Non-Freezers) were instructed to walk in two virtual environments: (i) across a plank that was located on the ground (LOW), (ii) across a plank above a deep pit (HIGH). Multiple synchronized motion capture cameras updated participants' movement through the virtual environment in real-time, while their gait was recorded. Anxiety levels were evaluated after each trial using self-assessment manikins. Freezers performed the experiment on two separate occasions (in their ON and OFF state). Freezers reported higher levels of anxiety compared to Non-Freezers (p<0.001) and all patients reported greater levels of anxiety when walking across the HIGH plank compared to the LOW (p<0.001). Freezers experienced significantly more freezing of gait episodes (p?=?0.013) and spent a significantly greater percentage of each trial frozen (p?=?0.005) when crossing the HIGH plank. This finding was even more pronounced when comparing Freezers in their OFF state. Freezers also had greater step length variability in the HIGH compared to the LOW condition, while the step length variability in Non-Freezers did not change. In conclusion, this was the first study to directly compare freezing of gait in anxious and non-anxious situations. These results present strong evidence that anxiety is an important mechanism underlying freezing of gait and supports the notion that the limbic system may have a profound contribution to freezing in PD. PMID:25250691

Ehgoetz Martens, Kaylena A.; Ellard, Colin G.; Almeida, Quincy J.

2014-01-01

444

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

445

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.

446

Emergence of Depression During Early Abstinence in Depressed and Non-Depressed Women Smokers  

Microsoft Academic Search

The emergence of depression early in a quit attempt and its relationship to ability to maintain abstinence were studied in 99 depressed and non-depressed women smokers. Participants rated withdrawal symptomatology during a baseline week and the first two weeks of a quit attempt, during which they used a 21-mg nicotine patch and received behavioral counseling. Depressed women experienced greater difficulty

Cynthia S. Pomerleau; Rebecca J. Namenek Brouwer; Ovide F. Pomerleau

2001-01-01

447

Ultrastructural effects of lethal freezing on brain, muscle and Malpighian tubules from freeze-tolerant larvae of the gall fly, Eurosta solidaginis  

Microsoft Academic Search

In preparation for winter low temperatures, larvae of the gall fly, Eurosta solidaginis, accumulate the cryoprotectants glycerol, sorbitol, and trehalose. The fat body cells of these freeze-tolerant larvae can survive intracellular freezing to ?80°C for 48 h even though no whole larvae survive this treatment. We hypothesized that some other tissue was more susceptible to freezing and therefore may be

Stephen D Collins; Allan L Allenspach; Richard E Lee

1997-01-01

448

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

449

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. PMID:22401842

Martin-Storey, Alexa; Crosnoe, Robert

2012-01-01

450

Microsoft PowerPoint - Jewell  

Cancer.gov

Measuring Biomarker Stability in Frozen Tissue Post-acquisition variables: • Time at room temperature • Temperature of room • Type of fixative • Time in fixative • Rate of freezingFreeze / Thaw • Size of aliquots • Storage temperature • Storage duration

451

Hormonal control of hemolymph lipoprotein ice nucleators in overwintering freeze-susceptible larvae of the stag beetle Ceruchus piceus: adipokinetic hormone and juvenile hormone  

Microsoft Academic Search

Freeze-resistant overwintering larvae of the stag beetle Ceruchus piceus do not produce antifreezes in winter, but instead lower their supercooling points by seasonal removal of lipoprotein ice nucleators (LPINs) from the hemolymph. The normal lipid transport function of these lipoproteins becomes less essential during winter because of the low temperatures and the diapause state of the larvae. Adipokinetic hormone (AKH)

Lei Xu; Lisa G. Neven; John G. Duman

1990-01-01

452

Preparation of Chitosan Nanocompositeswith a Macroporous Structure by Unidirectional Freezing and Subsequent Freeze-Drying  

PubMed Central

Chitosan is the N-deacetylated derivative of chitin, a naturally abundant mucopolysaccharide that consists of 2-acetamido-2-deoxy-?-d-glucose through a ? (1?4) linkage and is found in nature as the supporting material of crustaceans, insects, etc. Chitosan has been strongly recommended as a suitable functional material because of its excellent biocompatibility, biodegradability, non-toxicity, and adsorption properties. Boosting all these excellent properties to obtain unprecedented performances requires the core competences of materials chemists to design and develop novel processing strategies that ultimately allow tailoring the structure and/or the composition of the resulting chitosan-based materials. For instance, the preparation of macroporous materials is challenging in catalysis, biocatalysis and biomedicine, because the resulting materials will offer a desirable combination of high internal reactive surface area and straightforward molecular transport through broad “highways” leading to such a surface. Moreover, chitosan-based composites made of two or more distinct components will produce structural or functional properties not present in materials composed of one single component. Our group has been working lately on cryogenic processes based on the unidirectional freezing of water slurries and/or hydrogels, the subsequent freeze-drying of which produce macroporous materials with a well-patterned structure. We have applied this process to different gels and colloidal suspensions of inorganic, organic, and hybrid materials. In this review, we will describe the application of the process to chitosan solutions and gels typically containing a second component (e.g., metal and ceramic nanoparticles, or carbon nanotubes) for the formation of chitosan nanocomposites with a macroporous structure. We will also discuss the role played by this tailored composition and structure in the ultimate performance of these materials. PMID:25421320