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Sample records for monitor ph change

  1. An electrochemical approach to monitor pH change in agar media during plant tissue culture.

    Science.gov (United States)

    Wang, Min; Ha, Yang

    2007-05-15

    In this work, metal oxide microelectrodes were developed to monitor pH change in agar media during plant tissue culture. An antimony wire was produced by a new approach "capillary melt method". The surface of the obtained antimony wire was oxidized in a potassium nitrate melt to fabricate an antimony oxide film for pH sensing. Characterization results show that the oxide layer grown on the wire surface consists of Sb(2)O(3) crystal phase. The sensing response, open-circuit potential, of the electrode has a good linear relationship (R(2)=1.00) with pH value of the test solution. Adding organic compounds into the test media would not affect the linear relationship, although the slope of the lines varied with different ingredients added. The antimony oxide electrodes were employed to continuously monitor pH change of agar culture media during a 2-week plant tissue culture of Dendrobium candidum. The antimony oxide electrode fabricated this way has the advantages of low cost, easy fabrication, fast response, and almost no contamination introduced into the system. It would be suitable for in situ and continuous pH measurement in many bio applications.

  2. Two rhodamine lactam modulated lysosome-targetable fluorescence probes for sensitively and selectively monitoring subcellular organelle pH change

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongmei [Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069 (China); Wang, Cuiling [Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi' an 710069 (China); She, Mengyao; Zhu, Yuelu; Zhang, Jidong; Yang, Zheng [Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069 (China); Liu, Ping, E-mail: liuping@nwu.edu.cn [Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069 (China); Wang, Yaoyu [Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069 (China); Li, Jianli, E-mail: lijianli@nwu.edu.cn [Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecule Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069 (China)

    2015-11-05

    Be a powerful technique for convenient detection of pH change in living cells, especially at subcellular level, fluorescent probes has attracted more and more attention. In this work, we designed and synthesized three rhodamine lactam modulated fluorescent probes RS1, RS2 and RS3, which all respond sensitively toward weak acidity (pH range 4–6) via the photophysical property in buffer solution without interference from the other metal ions, and they also show ideal pKa values and excellent reversibility. Particularly, by changing the lone pair electrons distribution of lactam-N atom with different conjugations, RS2 and RS3 exhibit high quantum yield, negligible cytotoxicity and excellent permeability. They are suitable to stain selectively lysosomes of tumor cells and monitor its pH changes sensitively via optical molecular imaging. The above findings suggest that the probes we designed could act as ideal and easy method for investigating the pivotal role of H{sup +} in lysosomes and are potential pH detectors in disease diagnosis through direct intracellular imaging. - Highlights: • Two probes for sensitively and selectively monitoring weak acidic pH change. • The pKa of the probes was highly suitable for staining lysosomes in tumor cells. • The properties of those probes were changed by different conjugate system. • These probes have negligible cytotoxicity and good sensitivity in vivo.

  3. Microscopic monitoring of extracellular pH in dental biofilms

    DEFF Research Database (Denmark)

    Schlafer, Sebastian; Garcia, Javier; Greve, Matilde

    pH in dental biofilm is a key virulence factor for the development of caries lesions. The complex three-dimensional architecture of dental biofilms leads to steep gradients of nutrients and metabolites, including organic acids, across the biofilm. For decades, measuring pH in dental biofilm has...... been limited to monitoring bulk pH with electrodes. Although pH microelectrodes with a better spatial resolution have been developed, they do not permit to monitor horizontal pH gradients in real-time. Quantitative fluorescent microscopic techniques, such as fluorescence lifetime imaging or pH...... ratiometry, can be employed to map the pH landscape in dental biofilm with more detail. However, when pH sensitive fluorescent probes are used to visualize pH in biofilms, it is crucial to differentiate between extracellular and intracellular pH. Intracellular microbial pH and pH in the extracellular matrix...

  4. Evaluation of fluorimetric pH sensors for bioprocess monitoring at low pH.

    Science.gov (United States)

    Janzen, Nils H; Schmidt, Michael; Krause, Christian; Weuster-Botz, Dirk

    2015-09-01

    Optical chemical sensors are the standard for pH monitoring in small-scale bioreactors such as microtiter plates, shaking flasks or other single-use bioreactors. The dynamic pH range of the so far commercially available fluorescent pH sensors applied in small-scale bioreactors is restricted to pH monitoring around neutral pH, although many fermentation processes are performed at pH ABE) with offline pH measurements with a standard glass electrode as reference.

  5. Chemical sensor network for pH monitoring

    Directory of Open Access Journals (Sweden)

    Claudia Manjarrés

    2016-02-01

    Full Text Available Monitoring of water sources is a major concern worldwide. Wireless sensor networks (WSN may be used for this monitoring. However, current systems employ mainly physical sensors for variables such as temperature, pressure, humidity and light. Wireless chemical sensors networks (WCSNs for environmental monitoring are scarce due to the lack of autonomy of conventional sensors. This paper presents results of a WCSN for monitoring pH based on ion selective field effect transistors (ISFETs. Sensing nodes employ a human interface required for in situ calibration of chemical sensors. Unlike most studies, our work evaluates the network employing chemical measurements and wireless network metrics. Results show zero packet losses by using a time division multiple access (TDMA protocol. The network allows wireless communication within 300 m including attenuation from buildings and trees. Therefore, the system presented in this paper is suitable for long range applications with unobstructed line of sight. pH measurements present a standard deviation below 1%, showing high repeatability. When compared to a commercial pH meter, difference in measurements is below 5%. As a consequence, accuracy is adequate for the application. Measurements also presented high stability during 3 h of continuous measurement.

  6. pH monitoring in patients with benign voice disorders

    DEFF Research Database (Denmark)

    Grøntved, A M; West, F

    2000-01-01

    The aim of this study was to compare oesophageal pH-metry with laryngeal signs and symptoms in patients suspected of laryngeal reflux disease. A total of 60 patients with voice disorders, who were suspected of laryngeal reflux, were tested by single probe oesophageal pH monitoring. Thirty....... It is important to realize that signs of reflux laryngitis are not confined to the posterior commisure....

  7. pH monitoring in patients with benign voice disorders

    DEFF Research Database (Denmark)

    Grøntved, A M; West, F

    2000-01-01

    wall granulation and increased muscle tension. The patients in the reflux group were given medical treatment using omeprazole, and 76% logopedic voice training program. More than 50% of the laryngeal reflux patients were treated for more than 4 months before their voice problems had resolved......The aim of this study was to compare oesophageal pH-metry with laryngeal signs and symptoms in patients suspected of laryngeal reflux disease. A total of 60 patients with voice disorders, who were suspected of laryngeal reflux, were tested by single probe oesophageal pH monitoring. Thirty...

  8. SALIVARY PH CHANGES AFTER GIC RESTORATION ON DECIDUOUS TEETH

    Directory of Open Access Journals (Sweden)

    Chandra Nila Sukma

    2015-06-01

    Full Text Available Glass Ionomer Cement (GIC is the most widely used material in pediatric dentistry. The purpose of this study was to analyze pH changes of saliva after GIC restoration on primary teeth. For this purpose, 20 primary canines which were restored with GIC 24 hours previously were plunged into 20 tubes containing each 1,5 ml pH 6,8 Fusayama artificial saliva and then stored in incubator at the temperature of 37°C. The pH changes were measured at 30, 60, and 90 minutes later with digital pH meter PH-201. It was revealed that the highest pH acceleration was at 30 minutes exposure an decrease thereafter and the lowest pH acceleration was at 90 minutes exposure. Statistical analysis was performed by Anova and Tukey HSD.

  9. Hydrogel-coated fiber Bragg grating sensor for pH monitoring

    Science.gov (United States)

    Pabbisetti, Vayu Nandana Kishore; Madhuvarasu, Sai Shankar

    2016-06-01

    We present a fiber-optic wavelength-modulated sensor for pH applications. Fiber Bragg grating (FBG) is functionalized with a stimulus-responsive hydrogel that induces a strain on FBG due to mechanical expansion of the gel in response to ambient pH changes. The gel is synthesized from the blends of poly (vinyl alcohol)/poly (acrylic acid). The induced strain results in a shift of FBG reflected peak that is monitored by an interrogator. The sensor system shows good linearity in the acidic pH range of 3 to 7 with a sensitivity of 12.16 pm/pH. In addition, it shows good repeatability and oscillator behavior, which proves it to be fit for pH sensing applications.

  10. Endoscopic pH Monitoring for Patients with Suspected or Refractory Gastroesophageal Reflux Disease

    Directory of Open Access Journals (Sweden)

    Brian G Turner

    2007-01-01

    Full Text Available BACKGROUND: Wireless pH studies can offer prolonged pH monitoring, which may potentially facilitate the diagnosis and management of patients with gastroesophageal reflux disease (GERD. The aim of the present study was to evaluate the detection rate of abnormal esophageal acid exposure using prolonged pH monitoring in patients with suspected or refractory GERD symptoms.

  11. New method for long-term monitoring of intragastric pH

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: Consecutive monitoring of intragastric pH using the Bravo(R) capsule.METHODS: We put threads through a Bravo(R) capsule and then affixed it to the gastric wall by endoscopic hemoclipping in seven subjects. Study data were uploaded to a computer via Datalink every 48 h. In this way, repeated monitoring of intragastric pH was undertaken.RESULTS: All subjects were able to monitor gastric pH over a 1-wk period, and five for > 2 wk. No complications were encountered during the monitoring.After pH monitoring, we safely retrieved the capsule endoscopically.CONCLUSION: Clipping a Bravo(R) capsule onto the gastric wall enabled long-term intragastric pH monitoring.This is a methodological report of pH monitoring over a period of > 2 wk.

  12. An Optical Sensor with Polyaniline-Gold Hybrid Nanostructures for Monitoring pH in Saliva

    Directory of Open Access Journals (Sweden)

    Chongdai Luo

    2017-03-01

    Full Text Available Saliva contains important personal physiological information that is related to some diseases, and it is a valuable source of biochemical information that can be collected rapidly, frequently, and without stress. In this article, we reported a new and simple localized surface plasmon resonance (LSPR substrate composed of polyaniline (PANI-gold hybrid nanostructures as an optical sensor for monitoring the pH of saliva samples. The overall appearance and topography of the substrates, the composition, and the wettability of the LSPR surfaces were characterized by optical and scanning electron microscope (SEM images, infrared spectra, and contact angles measurement, respectively. The PANI-gold hybrid substrate readily responded to the pH. The response time was very short, which was 3.5 s when the pH switched from 2 to 7, and 4.5 s from 7 to 2. The changes of visible-near-infrared (NIR spectra of this sensor upon varying pH in solution showed that—for the absorption at given wavelengths of 665 nm and 785 nm—the sensitivities were 0.0299 a.u./pH (a.u. = arbitrary unit with a linear range of pH = 5–8 and 0.0234 a.u./pH with linear range of pH = 2–8, respectively. By using this new sensor, the pH of a real saliva sample was monitored and was consistent with the parallel measurements with a standard laboratory method. The results suggest that this novel LSPR sensor shows great potential in the field of mobile healthcare and home medical devices, and could also be modified by different sensitive materials to detect various molecules or ions in the future.

  13. EVALUATION OF A NEW CATHETER FOR ESOPHAGEAL PH MONITORING

    NARCIS (Netherlands)

    KUIT, JA; SCHEPEL, SJ; BIJLEVELD, CMA; KLEIBEUKER, JH

    1991-01-01

    A new catheter, provided with an Ion Sensitive Field Effect Transistor as a pH sensor and incorporating a reference electrode, was evaluated for esophageal pH recording. The pH-sensitivity was 54 mV/pH in vitro, with a linear response between pH 2 and pH 9. Clinical semi-ambulatory 24-hour esophagea

  14. EVALUATION OF A NEW CATHETER FOR ESOPHAGEAL PH MONITORING

    NARCIS (Netherlands)

    KUIT, JA; SCHEPEL, SJ; BIJLEVELD, CMA; KLEIBEUKER, JH

    1991-01-01

    A new catheter, provided with an Ion Sensitive Field Effect Transistor as a pH sensor and incorporating a reference electrode, was evaluated for esophageal pH recording. The pH-sensitivity was 54 mV/pH in vitro, with a linear response between pH 2 and pH 9. Clinical semi-ambulatory 24-hour esophagea

  15. Micro Electrochemical pH Sensor Applicable for Real-Time Ratiometric Monitoring of pH Values in Rat Brains.

    Science.gov (United States)

    Zhou, Jie; Zhang, Limin; Tian, Yang

    2016-02-16

    To develop in vivo monitoring meter for pH measurements is still the bottleneck for understanding the role of pH plays in the brain diseases. In this work, a selective and sensitive electrochemical pH meter was developed for real-time ratiometric monitoring of pH in different regions of rat brains upon ischemia. First, 1,2-naphthoquinone (1,2-NQ) was employed and optimized as a selective pH recognition element to establish a 2H(+)/2e(-) approach over a wide range of pH from 5.8 to 8.0. The pH meter demonstrated remarkable selectivity toward pH detection against metal ions, amino acids, reactive oxygen species, and other biological species in the brain. Meanwhile, an inner reference, 6-(ferrocenyl)hexanethiol (FcHT), was selected as a built-in correction to avoid the environmental effect through coimmobilization with 1,2-NQ. In addition, three-dimensional gold nanoleaves were electrodeposited onto the electrode surface to amplify the signal by ∼4.0-fold and the measurement was achieved down to 0.07 pH. Finally, combined with the microelectrode technique, the microelectrochemical pH meter was directly implanted into brain regions including the striatum, hippocampus, and cortex and successfully applied in real-time monitoring of pH values in these regions of brain followed by global cerebral ischemia. The results demonstrated that pH values were estimated to 7.21 ± 0.05, 7.13 ± 0.09, and 7.27 ± 0.06 in the striatum, hippocampus, and cortex in the rat brains, respectively, in normal conditions. However, pH decreased to 6.75 ± 0.07 and 6.52 ± 0.03 in the striatum and hippocampus, upon global cerebral ischemia, while a negligible pH change was obtained in the cortex.

  16. Differential Sensor for PH Monitoring of Environmental Objects

    Directory of Open Access Journals (Sweden)

    Romanenko Sergey

    2016-01-01

    Full Text Available Differential pH sensor is proposed. Reference electrode and measuring electrode are the same type. Reference electrode is immersed in standard buffer solution with known pH value. The differential pH sensor has longer service life as compared with the traditionally used sensors with silver chloride reference electrode. Ultrasonic cleaning system is proposed to clean the primary measuring transducer from pollution that form as result of silting during long-term operation with the sensor.

  17. Seasonal and long-term changes in pH in the Dutch coastal zone

    NARCIS (Netherlands)

    Provoost, P.; van Heuven, S.; Soetaert, K.; Laane, R. W. P. M.; Middelburg, J. J.

    2010-01-01

    Recent observations and modelling studies suggest that biogeochemical changes can mask atmospheric CO(2)-induced pH decreases. Data collected by the Dutch monitoring authorities in different coastal systems (North Sea, Wadden Sea, Ems-Dollard, Eastern Scheldt and Scheldt estuary) since 1975 provide

  18. Low reproducibility of 2 x 24-hour continuous esophageal pH monitoring in infants and children

    DEFF Research Database (Denmark)

    Nielsen, Rasmus; Kruse-Andersen, Søren; Husby, Steffen

    2003-01-01

    be taken into consideration when evaluating gastroesophageal reflux disease in infants and children by means of pH monitoring. The day-to-day variability limits the use of simultaneous pH monitoring and dietary challenges as a procedure to identify a possible causative relation between GERD and dietary...... the degree of reproducibility to endoscopic evidence of mucosal injury. Upper endoscopy and 2 x 24-hr consecutive pH monitoring were performed in 30 infants and children referred for gastroesophageal reflux disease. The monitoring was performed without dietary or activity restrictions in order to assess......, yielding an overall reproducibility of 70%. The limits of agreement for RI at day 2 were 0.2-3.3 times the initially obtained value at day 1. No difference was found in terms of reproducibility between groups with and without esophageal mucosal changes (erythema and esophagitis). No significant difference...

  19. 40 CFR 401.17 - pH Effluent limitations under continuous monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 28 2010-07-01 2010-07-01 true pH Effluent limitations under... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GENERAL PROVISIONS § 401.17 pH Effluent limitations under continuous monitoring. (a) Where a permittee continuously measures the pH of wastewater pursuant to...

  20. Diagnostic yield of oesophageal pH monitoring in patients with chronic unexplained cough

    NARCIS (Netherlands)

    Bogte, Auke; Bredenoord, Arjan J.; Smout, Andre J. P. M.

    2008-01-01

    Objective. One of the main causes of persistent cough is gastro-oesophageal reflux. In these patients, excessive oesophageal acid exposure and/or a temporal association between gastro-oesophageal reflux and cough can be demonstrated during 24-h pH monitoring. Impedance pH monitoring may have a highe

  1. Diagnostic yield of oesophageal pH monitoring in patients with chronic unexplained cough

    NARCIS (Netherlands)

    Bogte, Auke; Bredenoord, Arjan J.; Smout, Andre J. P. M.

    2008-01-01

    Objective. One of the main causes of persistent cough is gastro-oesophageal reflux. In these patients, excessive oesophageal acid exposure and/or a temporal association between gastro-oesophageal reflux and cough can be demonstrated during 24-h pH monitoring. Impedance pH monitoring may have a

  2. Blood perfusion and pH monitoring in organs by laser-induced fluorescence spectroscopy

    Science.gov (United States)

    Vari, Sandor G.; Papazoglou, Theodore G.; Pergadia, Vani R.; Stavridi, Marigo; Snyder, Wendy J.; Papaioannou, Thanassis; Duffy, J. T.; Weiss, Andrew B.; Thomas, Reem; Grundfest, Warren S.

    1994-01-01

    Sensitivity of laser-induced fluorescence spectroscopy (LIFS) in detecting a change in tissue pH, and blood perfusion was determined. Rabbits were anesthetized, paralyzed, and mechanically ventilated. The arterial and venous blood supplies of the kidney were isolated and ligated to alter the perfusion. The femoral artery was cannulated to extract samples for blood gas analysis. A 308-nm XeCl was used as an excitation source. A 600 micrometers core diameter fiber was used for fluorescence acquisition, and the spectra analyzed by an optical multichannel analyzer (EG & G, OMA III). the corresponding intensity ratio R equals INADH / ICOLL was used as an index for respiratory acidosis. Blood perfusion was assessed using the following algorithm: (IELAS minus ICOLL) divided by (INADH minus ICOLL). The intensity ratio linearly decreased with the reduction of blood perfusion. When we totally occluded the artery the ratio decreased tenfold when compared to the ratio of a fully perfused kidney. Results of monitoring blood acidosis by laser-induced fluorescence spectroscopy shows a significant trend between pH and intensity ratio. Since all the slopes were negative, there is an obvious significant correlation between the pH and NADH.COLLAGEN RATIO. Blue-light-induced fluorescence measurements and ratio fluorometry is a sensitive method for monitoring blood perfusion and acidity or alkalinity of an organ.

  3. Kinetics of onset of mouse sperm acrosome reaction induced by solubilized zona pellucida: fluorimetric determination of loss of pH gradient between acrosomal lumen and medium monitored by dapoxyl (2-aminoethyl) sulfonamide and of intracellular Ca(2+) changes monitored by fluo-3.

    Science.gov (United States)

    Rockwell, P L; Storey, B T

    2000-03-01

    The onset of the zona pellucida-induced acrosome reaction in mouse sperm is marked by loss of the pH gradient existing in acrosome-intact sperm between the acidic acrosomal lumen and the suspending medium, due to pore formation between outer acrosomal and plasma membranes. In earlier work, it was shown that this pH gradient loss occurred in single sperm bound to structurally intact zonae pellucidae with a half-time of 2.1 min; the extended kinetics of this loss determined in a sperm population bound to intact zonae was due to a 180-min range of variable lag times. We hypothesized that this lag time range was due to steric constraints imposed by the three-dimensional structure of the structurally intact zona pellucida, and that this constraint should be removed in solubilized zonae. The fluorescent probe, Dapoxyl(TM) (2-aminoethyl)sulfonamide (DAES) allowed a test of this hypothesis in a population of sperm cells. It is a weak base that is non-fluorescent in aqueous solution, but which accumulates in the acidic acrosomal compartment due to the pH gradient with highly enhanced fluorescence; loss of the pH gradient leads to a decrease in fluorescence. The half-time for DAES fluorescence loss in a population of capacitated, acrosome-intact sperm in response to solubilized zona pellucida protein was 2.13 +/- 0.10 min (SEM, n = 9). The agreement between single cell and cell population kinetics validates the hypothesis of steric constraint in the structurally intact zona pellucida. The change in intracellular Ca(2+) concentration in response to solubilized zona pellucida, as monitored with fluo-3, was a rapid increase, followed by a decrease, with a half-time of 0.85 +/- 0.09 min (SEM, n = 6) to a steady state level higher than the initial level, indicating this Ca(2+) transient as the precursor reaction to onset of the zona-induced acrosome reaction. Copyright 2000 Wiley-Liss, Inc.

  4. Time course of pH change in plant epidermis using microscopic pH imaging system

    Science.gov (United States)

    Dan, Risako; Shimizu, Megumi; Kazama, Haruko; Sakaue, Hirotaka

    2010-11-01

    We established a microscopic pH imaging system to track the time course of pH change in plant epidermis in vivo. In the previous research, we have found out that anthocyanin containing cells have higher pH. However, it was not clear whether the anthocyanin increased the pH or anthocyanin was synthesized result from the higher pH. Therefore, we further investigated the relationship between anthocyanin and pH change. To track the time course of pH change in plant epidermis, we established a system using luminescent imaging technique. We used HPTS (8-Hydroxypyrene-1,3,6-Trisulfonate) as pH indicator and applied excitation ratio imaging method. Luminescent image was converted to a pH distribution by obtained in vitro calibration using known pH solution. Cellular level observation was enabled by merging microscopic color picture of the same region to the pH change image. The established system was applied to epidermal cells of red-tip leaf lettuce, Lactuca Sativa L. and the time course was tracked in the growth process. We would discuss about the relationship between anthocyanin and pH change in plant epidermis.

  5. RTEMIS: Real-time Tumoroid and Environment Monitoring Using Impedance Spectroscopy and pH Sensing

    Science.gov (United States)

    Alexander, Frank A., Jr.

    This research utilizes Electrical Impedance Spectroscopy, a technique classically used for electrochemical analysis and material characterization, as the basis for a non-destructive, label-free assay platform for three dimensional (3D) cellular spheroids. In this work, a linear array of microelectrodes is optimized to rapidly respond to changes located within a 3D multicellular model. In addition, this technique is coupled with an on chip micro-pH sensor for monitoring the environment around the cells. Finally, the responses of both impedance and pH are correlated with physical changes within the cellular model. The impedance analysis system realized through this work provides a foundation for the development of high-throughput drug screening systems that utilize multiple parallel sensing modalities including pH and impedance sensing in order to quickly assess the efficacy of specific drug candidates. The slow development of new drugs is mainly attributed to poor predictability of current chemosensitivity and resistivity assays, as well as genetic differences between the animal models used for tests and humans. In addition, monolayer cultures used in early experimentation are fundamentally different from the complex structure of organs in vivo. This requires the study of smaller 3D models (spheroids) that more efficiently replicate the conditions within the body. The main objective of this research was to develop a microfluidic system on a chip that is capable of deducing viability and morphology of 3D tumor spheroids by monitoring both the impedance of the cellular model and the pH of their local environment. This would provide a fast and reliable method for screening pharmaceutical compounds in a high-throughput system.

  6. Seasonal and long-term changes in pH in the Dutch coastal zone

    Directory of Open Access Journals (Sweden)

    P. Provoost

    2010-11-01

    Full Text Available Recent observations and modelling studies suggest that biogeochemical changes can mask atmospheric CO2-induced pH decreases. Data collected by the Dutch monitoring authorities in different coastal systems (North Sea, Wadden Sea, Ems-Dollard, Eastern Scheldt and Scheldt estuary since 1975 provide an excellent opportunity to test whether this is the case in the Dutch coastal zone. The time-series were analysed using Multi-Resolution Analysis (MRA which resulted in the identification of system-dependent patterns on both seasonal and intra-annual time scales. The observed rates of pH change greatly exceed those expected from enhanced CO2 uptake, thus suggesting that other biogeochemical processes, possibly related to changes in nutrient loading, can play a dominant role in ocean acidification.

  7. [Prolonged esophageal pH monitoring utilization in the diagnosis of pathologic reflux in neonates

    Science.gov (United States)

    Mezzacappa, M A; Collares, E F

    1999-01-01

    OBJECTIVES: To present indications and results of prolonged esophageal pH monitoring in diagnosing pathologic gastroesophageal reflux in newborns during their stay in the neonatal unit. METHODS: This retrospective descriptive-analytical study of 85 prolonged esophageal pH monitoring in neonates was performed, between October 1995 and March 1998, in a tertiary intensive care unity. A Digitrapper MKIII device, pH probes with one or two channels, and antimony electrodes were utilized. The probe was placed 3 cm above the gastroesophageal junction. RESULTS: The main indications of this esophageal pH study were hypoxemia episodes demanding supplemental oxygen, and caffeine resistant apnea. The means -/+ SD of birth-weight and gestational age in the patients evaluated were, respectively, 1,204-/+460 g and 30.5 -/+ 2.9 weeks. There was no statistical difference observed in newborns with and without pathologic gastroesophageal reflux according to clinical manifestations and monitoring conditions. Forty-eight newborns (56.4%) presented 17.6-/+9.1% of the whole examination time with a pH below 4. Of these patients, 31.1% presented birth-weight below 1,000 g. Duodenogastroesophagic was diagnosed in two cases. Of the studied premature with chronic lung disease, 66.7% presented pathologic reflux. CONCLUSION: Prolonged pH esophageal monitoring is helpful in the differential diagnosis of the unspecific and very frequent clinic manifestations in very low birth-weight infants.

  8. Oropharyngeal 24-Hour pH Monitoring in Children With Airway-Related Problems

    Science.gov (United States)

    Mesallam, Tamer A.

    2016-01-01

    Objectives Diagnosis and clinical presentation of pediatric laryngopharyngeal reflux (LPR) is still controversial. The aims of this work were to study the possibility of performing 24-hour oropharyngeal pH monitoring for children in the outpatient clinic setup and to explore the results of this test in correlation to airway-related problems. Methods In this descriptive qualitative study, 26 children suffering from airway-related problems were included. Oropharyngeal 24-hour pH monitoring was performed for all subjects in the outpatient clinic setting. The distribution of airway diagnoses among the study group was studied versus the results of the pH monitoring. Results There were 16 males and 10 females participated in the study with a mean age of 6.88 (SD, ±5.77) years. Thirty-five percent of the patients were under the age of 3 years (range, 11 months to 3 years). Eight-five percent of the patients tolerated the pH probe insertion and completed 24-hour of pH recording. Laryngomalacia and subglottic stenosis (SGS) were more frequently reported in the positive LPR patients (77%). Conclusion Oropharyngeal 24-hour pH monitoring can be conducted for children in the outpatient setup even in young age children below 3 years old. Among the positive LPR group, SGS and laryngomalacia were the most commonly reported airway findings. PMID:27090271

  9. Continuous intra-arterial blood pH monitoring in rabbits with acid-base disorders.

    Science.gov (United States)

    Jin, Weizhong; Jiang, Jinjun; Wang, Xun; Zhu, Xiaodan; Wang, Guifang; Song, Yuanlin; Bai, Chunxue

    2011-07-31

    The acid-base balance of arterial blood is important for the clinical management of seriously ill patients, especially patients with acute lung injury or acute respiratory distress syndrome. We developed a novel fluorosensor for continuous blood pH monitoring and evaluated its performance both in vitro and in vivo in rabbits with acid-base disorders. The pH sensor is made of N-allyl-4-piperazinyl-1, 8-napthalimide and 2-hydroxyethyl methacrylate, which were bonded at the distal end of the optical fiber. The fluorescence intensity increased as the pH decreased with good reproducibility, selectivity and linearity in the pH range of 6-8. The pH measurement precision was 0.03 ± 0.03 pH units with a bias of -0.02 ± 0.04 (n = 105) and -0.00 ± 0.05 pH units (n=189) in rabbits with metabolic and respiratory acid-base orders, respectively. The optical pH sensor can accurately measure pH fluctuations with a fast response and is a promising candidate for continuous in-line measurements of blood pH in critical care patients.

  10. Computer model of unstirred layer and intracellular pH changes. Determinants of unstirred layer pH.

    Science.gov (United States)

    Marrannes, Roger

    2013-06-01

    Transmembrane acid-base fluxes affect the intracellular pH and unstirred layer pH around a superfused biological preparation. In this paper the factors influencing the unstirred layer pH and its gradient are studied. An analytical expression of the unstirred layer pH gradient in steady state is derived as a function of simultaneous transmembrane fluxes of (weak) acids and bases with the dehydration reaction of carbonic acid in equilibrium. Also a multicompartment computer model is described consisting of the extracellular bulk compartment, different unstirred layer compartments and the intracellular compartment. With this model also transient changes and the influence of carbonic anhydrase (CA) can be studied. The analytical expression and simulations with the multicompartment model demonstrate that in steady state the unstirred layer pH and its gradient are influenced by the size and type of transmembrane flux of acids and bases, their dissociation constant and diffusion coefficient, the concentration, diffusion coefficient and type of mobile buffers and the activity and location of CA. Similar principles contribute to the amplitude of the unstirred layer pH transients. According to these models an immobile buffer does not influence the steady-state pH, but reduces the amplitude of pH transients especially when these are fast. The unstirred layer pH provides useful information about transmembrane acid-base fluxes. This paper gives more insight how the unstirred layer pH and its transients can be interpreted. Methodological issues are discussed.

  11. Tunable electrochemical pH modulation in a microchannel monitored via the proton-coupled electro-oxidation of hydroquinone.

    Science.gov (United States)

    Contento, Nicholas M; Bohn, Paul W

    2014-07-01

    Electrochemistry is a promising tool for microfluidic systems because it is relatively inexpensive, structures are simple to fabricate, and it is straight-forward to interface electronically. While most widely used in microfluidics for chemical detection or as the transduction mechanism for molecular probes, electrochemical methods can also be used to efficiently alter the chemical composition of small (typically microchannel Pt band electrode to increase microchannel pH. The change in microchannel pH is simultaneously tracked at a downstream electrode by monitoring changes in the i-V characteristics of the proton-coupled electro-oxidation of hydroquinone, thus providing real-time measurement of the protonated forms of hydroquinone from which the pH can be determined in a straightforward manner. Relative peak heights for protonated and deprotonated hydroquinone forms are in good agreement with expected pH changes by measured electrolysis rates, demonstrating that solvent electrolysis can be used to provide tunable, quantitative pH control within a microchannel.

  12. Simultaneous tracheal and oesophageal pH monitoring during mechanical ventilation.

    Science.gov (United States)

    Hue, V; Leclerc, F; Gottrand, F; Martinot, A; Crunelle, V; Riou, Y; Deschildre, A; Fourier, C; Turck, D

    1996-01-01

    OBJECTIVE: To simultaneously record tracheal and oesophageal pH in mechanically ventilated children to determine: (1) the feasibility and safety of the method; (2) the incidence of gastro-oesophageal reflux (GOR) and pulmonary contamination; and (3) their associated risk factors. DESIGN: Prospective study. SETTING: Paediatric intensive care unit in a university hospital. PATIENTS: Twenty mechanically ventilated children (mean age 6.7 years) who met the following inclusion criteria: endotracheal tube with an internal diameter of 4 mm or more (cuffed or uncuffed), mechanical ventilation for an acute disease, no treatment with antiacids, prokinetics, or H2-receptor blockers, and no nasogastric or orogastric tube. METHODS: The tracheal antimony pH probe was positioned 1 cm below the distal end of the endotracheal tube. The oesophageal antimony pH probe was positioned at the lower third of the oesophagus. pH was recorded on a double channel recorder and analysed with EsopHogram 5.01 software and by examination of the trace. The following definitions were used: GOR index, percentage of time pH 4.8%; tracheal reflux, fall in tracheal pH Tracheal reflux (pH aspiration. Episodes of tracheal reflux were associated with a GOR index > 10% (p tracheal and oesophageal pH monitoring was feasible in the setting of this study. Tracheal reflux can occur without pathological GOR, and GOR may occur without tracheal reflux. Further prospective studies in larger groups of patients are now justified. PMID:8813870

  13. [Vulvovaginitis: vaginal pH changes and associated microflora].

    Science.gov (United States)

    Saturnino, Ana Conceiçáo Ribeiro Dantas; Sisenando, Herbert Ary Arzabe Anteza Costa Nóbrega; Pereira, Alessandra Ramalho; Vale, Ana Patrícia Medeiros; Pires, Leila Monte; de Araújo, Jarine Torres; Ramos, Eleni Souto Nóbrega

    2005-01-01

    To establish a correlation between pH vaginal and the microflora associated in carriers of vulvovaginites. In the present study, the cytopathological examination and the vaginal flow in a group of 65 sexually active women had been carried through, 20 and 72 years, taken care of in the Laboratório de Citologia Clínica do Departamento de Análises Clínicas e Toxicológicas da Universidade Federal do Rio Grande do Norte, for determination of microorganisms in cervicovaginal sample and of pH in the vaginal flow. Associating pH vaginal with the presence of vulvovaginitis, it was evidenced that the Candida sp. occurred more frequently in pH 4.0, Trichomonas vaginalis in pH 6.0, Gardnerella vaginalis in pH 5.0, coconuts in pH 5.0, bacilli in pH 4.0 and cocos/bacilos in pH 6.0. It was observed that all the patients had presented at least one type of ethiological agent of vulvovaginiti and an associated microflora. The joint accomplishment of the cytological examinations and the determination of pH revealed important for directing the microflora associated with the vulvovaginiti, suggesting, of this form, that pH vaginal plays preponderant role how much to the presence of the infectious agents in the vaginal ecosystem.

  14. Monitoring, analysing, forecasting and communicating phenological changes

    NARCIS (Netherlands)

    Vliet, van A.J.H.

    2008-01-01

    The main objectives of this PhD thesis are to assess the climate-induced phenological changes in The Netherlands, to increase the knowledge and understanding of the ecological and socio-economic impacts of these phenological changes, to determine how society can adapt to these phenological changes a

  15. Monitoring, analysing, forecasting and communicating phenological changes

    NARCIS (Netherlands)

    Vliet, van A.J.H.

    2008-01-01

    The main objectives of this PhD thesis are to assess the climate-induced phenological changes in The Netherlands, to increase the knowledge and understanding of the ecological and socio-economic impacts of these phenological changes, to determine how society can adapt to these phenological changes

  16. Development of Online Spectroscopic pH Monitoring for Nuclear Fuel Reprocessing Plants: Weak Acid Schemes.

    Science.gov (United States)

    Casella, Amanda J; Ahlers, Laura R H; Campbell, Emily L; Levitskaia, Tatiana G; Peterson, James M; Smith, Frances N; Bryan, Samuel A

    2015-05-19

    In nuclear fuel reprocessing, separating trivalent minor actinides and lanthanide fission products is extremely challenging and often necessitates tight pH control in TALSPEAK (Trivalent Actinide-Lanthanide Separation by Phosphorus reagent Extraction from Aqueous Komplexes) separations. In TALSPEAK and similar advanced processes, aqueous pH is one of the most important factors governing the partitioning of lanthanides and actinides between an aqueous phase containing a polyaminopolycarboxylate complexing agent and a weak carboxylic acid buffer and an organic phase containing an acidic organophosphorus extractant. Real-time pH monitoring would significantly increase confidence in the separation performance. Our research is focused on developing a general method for online determination of the pH of aqueous solutions through chemometric analysis of Raman spectra. Spectroscopic process-monitoring capabilities, incorporated in a counter-current centrifugal contactor bank, provide a pathway for online, real-time measurement of solution pH. The spectroscopic techniques are process-friendly and can be easily configured for online applications, whereas classic potentiometric pH measurements require frequent calibration/maintenance and have poor long-term stability in aggressive chemical and radiation environments. Raman spectroscopy discriminates between the protonated and deprotonated forms of the carboxylic acid buffer, and the chemometric processing of the Raman spectral data with PLS (partial least-squares) regression provides a means to quantify their respective abundances and therefore determine the solution pH. Interpretive quantitative models have been developed and validated under a range of chemical composition and pH conditions using a lactic acid/lactate buffer system. The developed model was applied to new spectra obtained from online spectral measurements during a solvent extraction experiment using a counter-current centrifugal contactor bank. The model

  17. Active transport, ion movements, and pH changes : I. The chemistry of pH changes.

    Science.gov (United States)

    Good, N E

    1988-10-01

    The transport of substances across cell membranes may be the most fundamental activity of living things. When the substance transported is any ion there can be a change in the concentration of hydrogen ions on the two sides of the membrane. These hydrogen ion concentration changes are not caused by fluxes of hydrogen ions although fluxes of hydrogen ions may sometimes be involved. The reason for the apparent contradiction is quite simple. All aqueous systems are subject to two constraints: (1) to maintain the charge balance, the sum of the cationic charges must equal the sum of the anionic charges and (2) the product of the molar concentration of H(+) and the molar concentration of OH(-), established and maintained by the association and the dissociation of water, remains always at 10(-14). As a consequence the concentrations of H(+) and OH(-) are determined uniquely by differences between the concentrations of the other cations and anions, with [H(+)] and [OH(-)] being dependent variables. Hydrogen ions and hydroxyl ions can be produced or consumed in local reactions whereas any strong ions such as Cl(-), Mg(2+), or K(+) can be neither produced nor consumed in biological reactions. Further consequences of these truisms are outlined here in terms of the chemistry of the kinds of reactions which can lead to pH changes.

  18. FerryBox-assisted monitoring of mixed layer pH in the Norwegian Coastal Current

    Science.gov (United States)

    Reggiani, Emanuele R.; King, Andrew L.; Norli, Marit; Jaccard, Pierre; Sørensen, Kai; Bellerby, Richard G. J.

    2016-10-01

    The evaluation of marine carbonate system variability and the impacts of ocean acidification (OA) on coastal marine ecosystems increasingly rely on monitoring platforms capable of delivering near real-time in situ carbonate system observations. These observations are also used for developing models and scenarios of OA, including potential impacts on marine ecosystem structure and function. An embedded flow-through spectrophotometric pH detection system has been developed alongside an underway seawater sampling system - termed a FerryBox - operating on ships of opportunity (SOOP), and can deliver a continuous data stream of mixed layer seawater pH with an in situ uncertainty of summer periods of 2015. Spring and summertime pH was generally 0.1 higher, and up to 0.255 higher, in comparison to winter pH observations. Here we show the necessity for a regular, high density monitoring approach, and the suitability of this pH detection technique for unmanned observational platforms.

  19. Assessment of duodenogastric reflux by combined continuous intragastric pH and bilirubin monitoring

    Institute of Scientific and Technical Information of China (English)

    Fei Dai; Jun Gong; Ru Zhang; Jin-Yan Luo; You-Ling Zhu; Xue-Qin Wang

    2002-01-01

    AIM: To assess the diagnostic value of a combination of continuous intragastric pH and bilirubin monitoring in the detection of duodenogastric reflux (DGR), and the effects of diet on the bilirubin absorbance.METHODS: 30 healthy volunteers were divided into twogroups: standard diet group (Group 1) 18 cases, free diet group (Group 2) 12 cases. Each subjects were subjected to simultaneous 24 hour intragastric pH and spectrophotometric bilirubin concentration monitoring (Bilitec 2000).RESULTS: There was no difference of preprandial phasebilirubin absorbance between two groups. The absorbanceof postprandial phase was significantly increased in group 2than group 1. There was no difference between preprandialphase and postprandial phase absorbance in group 1.Postprandial phase absorbance was significantly higher ingroup 2. In a comparison of bile reflux with intragastric pHduring night time, there were 4 types of reflux:Simultaneous increase in absorbance and pH in only 19.6%, increase in bilirubin with unchanged pH 33. 3 %, pHincrease with unchanged absorbance 36. 3 %, and bothunchanged in 10. 8 %. Linear regression analysis showed nocorrelation between percertage total time of pH < 4 aridpercentage total time of absortance > 0. 14, r=0.068, P<0.05.CONCLUSION: Because of the dietary effect, highabsorbance fluids or foods should be avoided in detection.Intrsgastric pH and bilirubin monitoring separately predictthe presence of duodenal (and/or pancreatic) reflux and bilereflux. They can not substitute for each other. The detectionof DGR is improved if the two parameters are combinedsimultanoously.

  20. Mitochondrial membrane studies using impedance spectroscopy with parallel pH monitoring.

    Directory of Open Access Journals (Sweden)

    Divya Padmaraj

    Full Text Available A biological microelectromechanical system (BioMEMS device was designed to study complementary mitochondrial parameters important in mitochondrial dysfunction studies. Mitochondrial dysfunction has been linked to many diseases, including diabetes, obesity, heart failure and aging, as these organelles play a critical role in energy generation, cell signaling and apoptosis. The synthesis of ATP is driven by the electrical potential across the inner mitochondrial membrane and by the pH difference due to proton flux across it. We have developed a tool to study the ionic activity of the mitochondria in parallel with dielectric measurements (impedance spectroscopy to gain a better understanding of the properties of the mitochondrial membrane. This BioMEMS chip includes: 1 electrodes for impedance studies of mitochondria designed as two- and four-probe structures for optimized operation over a wide frequency range and 2 ion-sensitive field effect transistors for proton studies of the electron transport chain and for possible monitoring other ions such as sodium, potassium and calcium. We have used uncouplers to depolarize the mitochondrial membrane and disrupt the ionic balance. Dielectric spectroscopy responded with a corresponding increase in impedance values pointing at changes in mitochondrial membrane potential. An electrical model was used to describe mitochondrial sample's complex impedance frequency dependencies and the contribution of the membrane to overall impedance changes. The results prove that dielectric spectroscopy can be used as a tool for membrane potential studies. It can be concluded that studies of the electrochemical parameters associated with mitochondrial bioenergetics may render significant information on various abnormalities attributable to these organelles.

  1. MONITORING VEGETATION CHANGE IN THE NETHERLANDS

    Directory of Open Access Journals (Sweden)

    P: BREMER

    2007-01-01

    Full Text Available The Dutch national vegetation monitoring scheme collects sample-based surveillance data at a national scale. The objectives are (i to assess if changes in eutrophication, acidification and desiccation lead to changes in the vegetation of natural habitats and (ii to assess changes in botanical quality of natural habitats and farmland and (iii to assess botanical changes in verges of traffic highways. The first results demonstrated that the national monitoring scheme is sensitive enough to track relevant changes in the vegetation. Examples are the increasing coverage of shrubs in natural areas and the signs of recovery of the vegetation of wet dune valleys in areas with hydrological measures.

  2. Can pH and electrical conductivity monitoring reveal spatial and temporal patterns in wetland geochemical processes?

    Directory of Open Access Journals (Sweden)

    P. J. Gerla

    2013-01-01

    Full Text Available Carbonate reactions and equilibria play a dominant role in the biogeochemical function of many wetlands. The US Geological Survey PHREEQC computer code was used to model geochemical reactions that may be typical for wetlands with water budgets characterized by: (a input dominated by direct precipitation, (b interaction with groundwater, (c variable degrees of reaction with organic carbon, and (d different rates of evapotranspiration. Rainfall with a typical composition was progressively reacted with calcite and organic carbon at various rates and proportions using PHREEQC. Contrasting patterns of the results suggest that basic water quality data collected in the field can reveal differences in the geochemical processes in wetlands. Given a temporal record, these can signal subtle changes in surrounding land cover and use. To demonstrate this, temperature, pH, and electrical conductivity (EC were monitored for three years in five large wetlands comprising 48 sample sites in northwest Minnesota. EC and pH of samples ranged greatly – from 23 to 1300 μS cm−1 and 5.5 to 9. The largest range in pH was observed in small beach ridge wetlands, where two clusters are apparent: (1 low EC and a wide range of pH and (2 higher pH and EC. Large marshes within a glacial lake – till plain have a broad range of pH and EC, but depend on the specific wetland. Outlying data typically occurred in altered or disturbed areas. The inter-annual and intra-wetland consistency of the results suggests that each wetland system hosts characteristic geochemical conditions.

  3. The Evaluation of Gastroesophageal Reflux Disease with Esophageal pH Monitorization in Children

    Directory of Open Access Journals (Sweden)

    Gülin Erdemir

    2009-12-01

    Full Text Available Introduction: Gastroesophageal reflux disease is named when gastroesophageal reflux becomes symptomatic, influences the life comfort, and results in morbidity. In this study, we aimed to evaluate the patients admitted with GER-associated symptoms with demographic characteristics, 24-hour esophageal pH monitorization results, and responses to different treatment protocols. Materials and Method: The data of patients who admitted to Uludag University Pediatrics Outpatient Clinic between January 2008 and September 2009 with GERD-associated symptoms and underwent esophageal pH monitorization was collected retrospectively. The associations between initial symptoms, 24-hour esophageal pH monitorization results, presence of accompanying disease, sociocultural conditions, and therapy responses were evaluated. Results: Ninety-two patients (37 female, 55 male were included and mean age was 4.42±4.33 (1 mo-18 years. The frequency of cough, vomiting and abdominal pain at admission were 49.5%, 47.3% and 22% respectively. Esophageal pH monitorization diagnosed GERD in 21 patients (22.8%. The frequency of symptoms in GERD patients who diagnosed with esophageal pH monitorization was; cough (n:15, 33.4%, vomiting (n:11, 25.6%, and abdominal pain (n:5, 22.3%. Among all complaints, cough was found to be significantly associated with GERD (p=0.041. Accompanying neurological disease was present in 13.1% (n:12, immunodeficiency 13.1% (n:12 and bronchial reactivity 13.1% (n:12. Therapy success was achieved in 57.7% of patients. Therapy response were similar with different therapy protocols (proton pump inhibitor+prokinetic+sucralfate, proton pump inhibitor+prokinetic, H2 receptor blocker+sucralfate, proton pump inhibitor+sucralfate, H2 receptor blocker+ prokinetic, monotherapy with proton pump inhibitor or H2 receptor blocker (p=0.068.Conclusion: GERD is a common childhood disease. Currently, diagnosis and treatment of GERD in children is still controversial. The

  4. Monitoring anaerobic sequential batch reactors via fractal analysis of pH time series.

    Science.gov (United States)

    Méndez-Acosta, H O; Hernandez-Martinez, E; Jáuregui-Jáuregui, J A; Alvarez-Ramirez, J; Puebla, H

    2013-08-01

    Efficient monitoring and control schemes are mandatory in the current operation of biological wastewater treatment plants because they must accomplish more demanding environmental policies. This fact is of particular interest in anaerobic digestion processes where the availability of accurate, inexpensive, and suitable sensors for the on-line monitoring of key process variables remains an open problem nowadays. In particular, this problem is more challenging when dealing with batch processes where the monitoring strategy has to be performed in finite time, which limits the application of current advanced monitoring schemes as those based in the proposal of nonlinear observers (i.e., software sensors). In this article, a fractal time series analysis of pH fluctuations in an anaerobic sequential batch reactor (AnSBR) used for the treatment of tequila vinasses is presented. Results indicated that conventional on-line pH measurements can be correlated with off-line determined key process variables, such as COD, VFA and biogas production via some fractality indexes.

  5. In vivo pH monitoring using boron doped diamond microelectrode and silver needles: application to stomach disorder diagnosis.

    Science.gov (United States)

    Fierro, Stéphane; Seishima, Ryo; Nagano, Osamu; Saya, Hideyuki; Einaga, Yasuaki

    2013-11-19

    This study presents the in vivo electrochemical monitoring of pH using boron doped diamond (BDD) microelectrode and silver needles for potential application in medical diagnosis. Accurate calibration curve for pH determination were obtained through in vitro electrochemical measurements. The increase induced in stomach pH by treatment with pantoprazole was used to demonstrate that it is possible to monitor the pH in vivo using the simple and noninvasive system proposed herein. Using the results of the in vivo and in vitro experiments, a quantitative analysis of the increase in stomach pH is also presented. It is proposed that the catheter-free pH monitoring system presented in this study could be potentially employed in any biological environment.

  6. Cadmium triggers Elodea canadensis to change the surrounding water pH and thereby Cd uptake.

    Science.gov (United States)

    Javed, M Tariq; Greger, Maria

    2011-01-01

    This study was aimed to investigate the influence of Elodea canadensis shoots on surrounding water pH in the presence of cadmium and the effect of plant-induced pH on cadmium uptake. The pH change in the surrounding nutrient solution and Cd uptake by Elodea shoots were investigated after cultivation of various plant densities (1, 3, 6 plants per 500 ml) in hydroponics at a starting pH of 4.0 and in the presence of different concentrations of cadmium (0, 0.1, 0.5 microM). Cadmium uptake was also investigated at different constant pH (4.0, 4.5, 5.5 and 6.5). To investigate if the pH change arose from photosynthetic activities, plants were grown under light, darkness or in the presence of a photosynthetic inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), and 0.5 microM cadmium in the solution. Elodea had an ability to increase the surrounding water pH, when the initial pH was low, which resulted in increased accumulation of Cd. The higher the plant density, the more pronounced was the pH change. The pH increase was not due to the photosynthetic activity since the pH rise was more pronounced under darkness and in the presence of DCMU. The pH increase by Elodea was triggered by cadmium.

  7. Ground and river water quality monitoring using a smartphone-based pH sensor

    Directory of Open Access Journals (Sweden)

    Sibasish Dutta

    2015-05-01

    Full Text Available We report here the working of a compact and handheld smartphone-based pH sensor for monitoring of ground and river water quality. Using simple laboratory optical components and the camera of the smartphone, we develop a compact spectrophotometer which is operational in the wavelength range of 400-700 nm and having spectral resolution of 0.305 nm/pixel for our equipment. The sensor measures variations in optical absorption band of pH sensitive dye sample in different pH solutions. The transmission image spectra through a transmission grating gets captured by the smartphone, and subsequently converted into intensity vs. wavelengths. Using the designed sensor, we measure water quality of ground water and river water from different locations in Assam and the results are found to be reliable when compared with the standard spectrophotometer tool. The overall cost involved for development of the sensor is relatively low. We envision that the designed sensing technique could emerge as an inexpensive, compact and portable pH sensor that would be useful for in-field applications.

  8. Ground and river water quality monitoring using a smartphone-based pH sensor

    Science.gov (United States)

    Dutta, Sibasish; Sarma, Dhrubajyoti; Nath, Pabitra

    2015-05-01

    We report here the working of a compact and handheld smartphone-based pH sensor for monitoring of ground and river water quality. Using simple laboratory optical components and the camera of the smartphone, we develop a compact spectrophotometer which is operational in the wavelength range of 400-700 nm and having spectral resolution of 0.305 nm/pixel for our equipment. The sensor measures variations in optical absorption band of pH sensitive dye sample in different pH solutions. The transmission image spectra through a transmission grating gets captured by the smartphone, and subsequently converted into intensity vs. wavelengths. Using the designed sensor, we measure water quality of ground water and river water from different locations in Assam and the results are found to be reliable when compared with the standard spectrophotometer tool. The overall cost involved for development of the sensor is relatively low. We envision that the designed sensing technique could emerge as an inexpensive, compact and portable pH sensor that would be useful for in-field applications.

  9. Monitoring change in Great Salt Lake

    Science.gov (United States)

    Naftz, David L.; Angeroth, Cory E.; Freeman, Michael L.; Rowland, Ryan C.; Carling, Gregory

    2013-01-01

    Despite the ecological and economic importance of Great Salt Lake, only limited water quality monitoring has occurred historically. To change this, new monitoring stations and networks—gauges of lake level height and rate of inflow, moored buoys, and multiple lake-bottom sensors—will provide important information that can be used to make informed decisions regarding future management of the Great Salt Lake ecosystem.

  10. Monitoring beach changes using GPS surveying techniques

    Science.gov (United States)

    Morton, Robert; Leach, Mark P.; Paine, Jeffrey G.; Cardoza, Michael A.

    1993-01-01

    A need exists for frequent and prompt updating of shoreline positions, rates of shoreline movement, and volumetric nearshore changes. To effectively monitor and predict these beach changes, accurate measurements of beach morphology incorporating both shore-parallel and shore-normal transects are required. Although it is possible to monitor beach dynamics using land-based surveying methods, it is generally not practical to collect data of sufficient density and resolution to satisfy a three-dimensional beach-change model of long segments of the coast. The challenge to coastal scientists is to devise new beach monitoring methods that address these needs and are rapid, reliable, relatively inexpensive, and maintain or improve measurement accuracy.

  11. Monitoring of extracellular pH in young dental biofilms grown in vivo in the presence and absence of sucrose

    DEFF Research Database (Denmark)

    Dige, Irene; Baelum, Vibeke; Nyvad, Bente

    2016-01-01

    BACKGROUND AND OBJECTIVE: pH in dental biofilms is of central importance for the development of caries. We used the ratiometric pH-sensitive dye C-SNARF-4 in combination with digital image analysis to monitor extracellular pH in dental biofilms grown in situ with and without sucrose supply. DESIG...

  12. Gastroesophageal manometry and 24-hour double pH monitoring in neonates with birth asphyxia

    Institute of Scientific and Technical Information of China (English)

    Mei Sun; Wei-Lin Wang; Wei Wang; De-Liang Wen; Hui Zhang; Yu-Kun Han

    2001-01-01

    @@ INTRODUCTION Birth asphyxia may lead to disturbances of gastroenteric motility of newborn infants[1.2] . The change of gut pressure and reflux are the major manifestations of the motor disturbance [3-9] . To evaluate the effects of perinatal asphyxia on the gastroenteric motility, gastric and esophageal pressure and double pH were measured in a group of asphyxiated newborns. And. their pathophysiological and anatomical effects on gastroenteric function were discussed.

  13. Change of pH during excess sludge fermentation under alkaline, acidic and neutral conditions.

    Science.gov (United States)

    Yuan, Yue; Peng, Yongzhen; Liu, Ye; Jin, Baodan; Wang, Bo; Wang, Shuying

    2014-12-01

    The change in pH during excess sludge (ES) fermentation of varying sludge concentrations was investigated in a series of reactors at alkaline, acidic, and neutral pHs. The results showed that the changes were significantly affected by fermentative conditions. Under different conditions, pH exhibited changing profiles. When ES was fermented under alkaline conditions, pH decreased in a range of (10±1). At the beginning of alkaline fermentation, pH dropped significantly, at intervals of 4h, 4h, and 5h with sludge concentrations of 8665.6mg/L, 6498.8mg/L, and 4332.5mg/L, then it would become moderate. However, under acidic conditions, pH increased from 4 to 5. Finally, under neutral conditions pH exhibited a decrease then an increase throughout entire fermentation process. Further study showed short-chain fatty acids (SCFAs), ammonia nitrogen and cations contributed to pH change under various fermentation conditions. This study presents a novel strategy based on pH change to predict whether SCFAs reach their stable stage.

  14. Efficient Web Change Monitoring with Page Digest

    Energy Technology Data Exchange (ETDEWEB)

    Buttler, D J; Rocco, D; Liu, L

    2004-02-20

    The Internet and the World Wide Web have enabled a publishing explosion of useful online information, which has produced the unfortunate side effect of information overload: it is increasingly difficult for individuals to keep abreast of fresh information. In this paper we describe an approach for building a system for efficiently monitoring changes to Web documents. This paper has three main contributions. First, we present a coherent framework that captures different characteristics of Web documents. The system uses the Page Digest encoding to provide a comprehensive monitoring system for content, structure, and other interesting properties of Web documents. Second, the Page Digest encoding enables improved performance for individual page monitors through mechanisms such as short-circuit evaluation, linear time algorithms for document and structure similarity, and data size reduction. Finally, we develop a collection of sentinel grouping techniques based on the Page Digest encoding to reduce redundant processing in large-scale monitoring systems by grouping similar monitoring requests together. We examine how effective these techniques are over a wide range of parameters and have seen an order of magnitude speed up over existing Web-based information monitoring systems.

  15. Changes in the morphology of influenza particles induced at low pH

    NARCIS (Netherlands)

    R.W.H. Ruigrok; A.F. Cremers; W.E.Ph. Beyer (Walter); F.M. de Ronde-Verloop

    1984-01-01

    textabstractAt low pH influenza virus causes membrane fusion. This phenomenon is thought to reflect a part of the infection mechanism of the virus. To obtain more information on the effect of low pH on the virus, the change in morphology of influenza virus particles was studied by electron microscop

  16. Carbon dots with strong excitation-dependent fluorescence changes towards pH. Application as nanosensors for a broad range of pH

    Energy Technology Data Exchange (ETDEWEB)

    Barati, Ali [Faculty of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan (Iran, Islamic Republic of); Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Shamsipur, Mojtaba, E-mail: mshamsipur@yahoo.com [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Abdollahi, Hamid, E-mail: abd@iasbs.ac.ir [Faculty of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan (Iran, Islamic Republic of)

    2016-08-10

    In this study, preparation of novel pH-sensitive N-doped carbon dots (NCDs) using glucose and urea is reported. The prepared NCDs present strong excitation-dependent fluorescence changes towards the pH that is a new behavior from these nanomaterials. By taking advantage of this unique behavior, two separated ratiometric pH sensors using emission spectra of the NCDs for both acidic (pH 2.0 to 8.0) and basic (pH 7.0 to 14.0) ranges of pH are constructed. Additionally, by considering the entire Excitation–Emission Matrix (EEM) of NCDs as analytical signal and using a suitable multivariate calibration method, a broad range of pH from 2.0 to 14.0 was well calibrated. The multivariate calibration method was independent from the concentration of NCDs and resulted in a very low average prediction error of 0.067 pH units. No changes in the predicted pH under UV irradiation (for 3 h) and at high ionic strength (up to 2 M NaCl) indicated the high stability of this pH nanosensor. The practicality of this pH nanosensor for pH determination in real water samples was validated with good accuracy and repeatability. - Highlights: • Novel pH-sensitive carbon dots with strong FL changes towards pH are reported. • Ratiometric FL pH-sensors for both acidic and basic ranges of pH are constructed. • Multivariate calibration methods were used to calibrate a broad range of pH. • Using EEM of carbon dots and ANN, pH from 2.0 to 14.0 was well calibrated. • The pH prediction is stable even at high ionic strength up to 2 M NaCl.

  17. Future changes in the Baltic Sea acid–base (pH) and oxygen balances

    National Research Council Canada - National Science Library

    Omstedt, ANDERS; Edman, Moa; Claremar, BJörn; Frodin, Peter; Gustafsson, ERIK; Humborg, CHRISTOPH; Hägg, HANNA; Mörth, MAGNUS; Rutgersson, ANNA; Schurgers, GUY; Smith, BENJAMIN; Wällstedt, TERESIA; Yurova, ALLA

    2012-01-01

    Possible future changes in Baltic Sea acid-base (pH) and oxygen balances were studied using a catchment-sea coupled model system and numerical experiments based on meteorological and hydrological forcing datasets and scenarios...

  18. Monitoring temporal changes of seismic properties

    Directory of Open Access Journals (Sweden)

    Yosuke eAoki

    2015-07-01

    Full Text Available Temporal changes of seismic properties, such as velocity, attenuation, anisotropy, and scattering properties, have been inferred by active methods for decades and more recently by passive methods. In particular, passive methods are capable of monitoring seismic properties because they do not require earthquakes but rely on continuously excited signals in the ocean, for example. A collection of continuous monitoring of seismic velocities has revealed that the susceptibility of velocity changes to stress perturbations are highly variable. These variations can be translated to variability of third-order elastic moduli, elastic moduli arising by considering finite deformation. The third-order elastic moduli are shown by theoretical studies to be a good indicator of granular properties of rocks and, in general, as to how fluids interact with solid rocks. Advancement of theoretical and observational studies will gain more insights into the nature of third-order elastic moduli, which will eventually become yet another parameters to characterize the properties of rocks.

  19. No file left behind - monitoring transfer latencies in PhEDEx

    CERN Document Server

    Ratnikova, Natalia

    2012-01-01

    The CMS experiment has to move Petabytes of data among dozens of computing centres with low latency in order to make efficient use of its resources. Transfer operations are well established to achieve the desired level of throughput, but operators lack a system to identify early on transfers that will need manual intervention to reach completion. File transfer latencies are sensitive to the underlying problems in the transfer infrastructure, and their measurement can be used as prompt trigger for preventive actions. For this reason, PhEDEx, the CMS transfer management system, has recently implemented a monitoring system to measure the transfer latencies at the level of individual files. For the first time now, the system can predict the completion time for the transfer of a data set. The operators can detect abnormal patterns in transfer latencies early, and correct the issues while the transfer is still in progress. Statistics are aggregated for blocks of files, recording a historical log to monitor the long...

  20. Monitoring Object Library Usage and Changes

    Science.gov (United States)

    Owen, R. K.; Craw, James M. (Technical Monitor)

    1995-01-01

    The NASA Ames Numerical Aerodynamic Simulation program Aeronautics Consolidated Supercomputing Facility (NAS/ACSF) supercomputing center services over 1600 users, and has numerous analysts with root access. Several tools have been developed to monitor object library usage and changes. Some of the tools do "noninvasive" monitoring and other tools implement run-time logging even for object-only libraries. The run-time logging identifies who, when, and what is being used. The benefits are that real usage can be measured, unused libraries can be discontinued, training and optimization efforts can be focused at those numerical methods that are actually used. An overview of the tools will be given and the results will be discussed.

  1. Development of On-Line Spectroscopic pH Monitoring for Nuclear Fuel Reprocessing Plants: Weak Acid Schemes

    Energy Technology Data Exchange (ETDEWEB)

    Casella, Amanda J.; Hylden, Laura R.; Campbell, Emily L.; Levitskaia, Tatiana G.; Peterson, James M.; Smith, Frances N.; Bryan, Samuel A.

    2015-05-19

    Knowledge of real-time solution properties and composition is a necessity for any spent nuclear fuel reprocessing method. Metal-ligand speciation in aqueous solutions derived from the dissolved commercial spent fuel is highly dependent upon the acid concentration/pH, which influences extraction efficiency and the resulting speciation in the organic phase. Spectroscopic process monitoring capabilities, incorporated in a counter current centrifugal contactor bank, provide a pathway for on-line real-time measurement of solution pH. The spectroscopic techniques are process-friendly and can be easily configured for on-line applications, while classic potentiometric pH measurements require frequent calibration/maintenance and have poor long-term stability in aggressive chemical and radiation environments. Our research is focused on developing a general method for on-line determination of pH of aqueous solutions through chemometric analysis of Raman spectra. Interpretive quantitative models have been developed and validated under the range of chemical composition and pH using a lactic acid/lactate buffer system. The developed model was applied to spectra obtained on-line during solvent extractions performed in a centrifugal contactor bank. The model predicted the pH within 11% for pH > 2, thus demonstrating that this technique could provide the capability of monitoring pH on-line in applications such as nuclear fuel reprocessing.

  2. Accurate positioning of the 24-hour pH monitoring catheter: Agreement between manometry and pH step-up method in two patient positions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate the agreement between esophageal manometry and pH step-up method in two different patient positions.METHODS: Eighteen subjects were included in the study. First, the distance from the nose to the proximal border of the lower esophageal sphincter (LES) was measured manometrically. Then a different investigator,who was blinded to the results of the first study,measured the same distance using the pH step-up method, with the patient in both upright and supine positions. An assessment of agreement between the two techniques was performed.RESULTS: In the supine position, the measurement of only one subject was outside the range accepted for correct positioning (≤ 3 cm distal or proximal to the LES). In the upright position, errors in measurement were recognized in five subjects. Bland-Altman plots revealed good agreement between measurements obtained manometrically and by the pH-step up method with the patient in the supine position.CONCLUSION: In the case of nonavailability of manometric detection device, the pH step-up method can facilitate the positioning of the 24 h pH monitoring catheter with the patient in the supine position. This should increase the use of pH-metry in clinical practice for subjects with suspected gastroesophageal reflux disease if our results are supported by further studies.

  3. Change point estimation in monitoring survival time.

    Directory of Open Access Journals (Sweden)

    Hassan Assareh

    Full Text Available Precise identification of the time when a change in a hospital outcome has occurred enables clinical experts to search for a potential special cause more effectively. In this paper, we develop change point estimation methods for survival time of a clinical procedure in the presence of patient mix in a Bayesian framework. We apply Bayesian hierarchical models to formulate the change point where there exists a step change in the mean survival time of patients who underwent cardiac surgery. The data are right censored since the monitoring is conducted over a limited follow-up period. We capture the effect of risk factors prior to the surgery using a Weibull accelerated failure time regression model. Markov Chain Monte Carlo is used to obtain posterior distributions of the change point parameters including location and magnitude of changes and also corresponding probabilistic intervals and inferences. The performance of the Bayesian estimator is investigated through simulations and the result shows that precise estimates can be obtained when they are used in conjunction with the risk-adjusted survival time CUSUM control charts for different magnitude scenarios. The proposed estimator shows a better performance where a longer follow-up period, censoring time, is applied. In comparison with the alternative built-in CUSUM estimator, more accurate and precise estimates are obtained by the Bayesian estimator. These superiorities are enhanced when probability quantification, flexibility and generalizability of the Bayesian change point detection model are also considered.

  4. Stopped-flow studies of spectral changes in bilirubin-human serum albumin following an alkaline pH jump and following binding of bilirubin

    DEFF Research Database (Denmark)

    Honoré, B

    1987-01-01

    A stopped-flow technique was used to study the spectral changes occurring in bilirubin-albumin following a pH jump as well as following binding of bilirubin at 25 degrees C. The changes were studied in two wavelength ranges, 280-310 nm (tyrosine residues) and 400-510 nm (bound bilirubin). The cha......A stopped-flow technique was used to study the spectral changes occurring in bilirubin-albumin following a pH jump as well as following binding of bilirubin at 25 degrees C. The changes were studied in two wavelength ranges, 280-310 nm (tyrosine residues) and 400-510 nm (bound bilirubin......). The changes were analyzed according to a scheme of consecutive unimolecular reactions. Spectral monitoring of a pH jump from 11.3 to 11.8 reveals that the bilirubin-albumin complex changes its structure in several steps. The UV absorption spectra show that 3.8 tyrosine residues ionize in the first step, 2......, indicating a change of the dihedral angle between the two bilirubin chromophores in a three-step reaction. It is suggested that 1 tyrosine residue is located close to the bilirubin site and is externalized in the second step. Bilirubin binding to albumin was monitored at two pH values, 11.3 and 11.8. At pH...

  5. Monitoring the conjunctiva for carbon dioxide and oxygen tensions and pH during cardiopulmonary bypass.

    Science.gov (United States)

    Weiss, Irwin K; Isenberg, Sherwin J; McArthur, David L; Del Signore, Madeline; McDonald, John S

    2011-03-01

    The purpose of this study was to measure, for the first time, multiple physiologic parameters of perfusion (pH, PCO2, PO2, and temperature) from the conjunctiva of adult patients during cardiopulmonary bypass while undergoing cardiothoracic surgery. Ten patients who underwent either intracardiac valve repair, atrial septal defect repair, or coronary artery bypass graft surgery had placement of a sensor which directly measured pH, PCO2, PO2, and temperature from the conjunctiva. Data were stratified into seven phases (0-5 minutes prior to bypass; 0-5, 6-10, and 11-15 minutes after initiation of bypass; 0-5 minutes prior to conclusion of bypass; and 0-5 and 6-10 minutes after bypass) and analyzed using a mixed model analysis.The change in conjunctival pH over the course of measurement was not statistically significant (p = .56). The PCO2 level followed a quadratic pattern, decreasing from a mean pre-bypass level of 37.7 mmHg at baseline prior to the initiation of cardiopulmonary bypass to a nadir of 33.2 mmHg, then increasing to a high of 39.4 mmHg at 6-10 minutes post bypass (p level of 79.5 mmHg to 31.3 mmHg by 6-10 minutes post bypass and even post-bypass, it never returned to baseline values (p levels as the patient was re-warmed following bypass (p < .01). There was no evidence of any eye injury or inflammation following the removal of the sensor. In the subjects studied, the conjunctival sensor yielded reproducible measurements during the various phases of cardiopulmonary bypass without ocular injury. Further study is necessary to determine the role of conjunctival measurements in critical settings.

  6. Twenty-four-hour esophageal pH monitoring in children and adolescents with chronic and/or recurrent rhinosinusitis

    Directory of Open Access Journals (Sweden)

    V.R.S.G. Monteiro

    2005-02-01

    Full Text Available Gastroesophageal reflux (GER disorder was studied in children and adolescents with chronic and/or recurrent rhinosinusitis not associated with bronchial asthma. Ten children with a clinical and radiological diagnosis of chronic and/or recurrent rhinosinusitis, consecutively attended at the Pediatric Otolaryngology Outpatient Clinic, Federal University of São Paulo, were evaluated. Prolonged esophageal pH monitoring was used to investigate GER disorder. The mean age of the ten patients evaluated (eight males was 7.4 ± 2.4 years. Two patients presented vomiting as a clinical manifestation and one patient presented retrosternal pain with a burning sensation. Twenty-four-hour esophageal pH monitoring was performed using the Sandhill apparatus. An antimony probe electrode was placed in the lower third of the esophagus, confirmed by fluoroscopy and later by a chest X-ray. The parameters analyzed by esophageal pH monitoring included: total percent time of the presence of acid esophageal pH, i.e., pH below 4 (<4.2%; total number of acid episodes (<50 episodes; number of reflux episodes longer than 5 min (3 or less, and duration of the longest reflux episode (<9.2 min. One patient (1/10, 10% presented a 24-h esophageal pH profile compatible with GER disorder. This data suggest that an association between chronic rhinosinusitis not associated with bronchial asthma and GER disorder may exist in children and adolescents, especially in those with compatible GER disorder symptoms. In these cases, 24-h esophageal pH monitoring should be performed before indicating surgery, since the present data suggest that 10% of chronic rhinosinusitis surgeries can be eliminated.

  7. Changes in interstitial K+ and pH during exercise: implications for blood flow regulation

    DEFF Research Database (Denmark)

    Juel, Carsten

    2007-01-01

    of fatigue. It has also been demonstrated with microdialysis that the interstitial decrease in pH during muscle activity is larger than the reduction in blood pH. Ion changes in the interstitium may affect blood flow directly or indirectly. Infusion of K+ into the femoral artery in humans has demonstrated...... that blood flow is affected by changes in K+ as low as 0.1 mmol/L. The vasodilatory effect of K+ can be inhibited with simultaneous barium infusion, indicating that inward rectifier potassium (Kir)channels are involved. Acidosis has a direct effect on blood flow and an indirect effect, mediated by changes...

  8. Fiber optic sensors for an in-situ monitoring of moisture and pH value in reinforced concrete

    Science.gov (United States)

    Grahn, Walter; Makedonski, Pavel; Wichern, Juergen; Kowalsky, Wolfgang; Wiese, Stefan

    2002-01-01

    Concrete structures such as social buildings and bridges are important economic goods. Thus, maintenance and preservation of these structures are of major interest. Buildings of reinforced concrete are exposed to a variety of damaging influences. In particular, moisture has an important influence on the lifetime of concrete structures. This is caused by the involvement of free water in corrosion of the steel, and the fact that water acts as transport medium for damaging ions such as chloride, sulfate, carbonate and ammonium. Thus, we designed and developed an integrated fiberoptical sensor system, which allows in-situ non- destructive long-term monitoring of concrete structures. As moisture indicator we use a pyridinium-N-phenolat betainital dye, which shows a strong solvatochromic behavior in the ultraviolet-visible spectral range (UV-VIS). The dye is embedded in a polymer matrix, whose moderate polarity is enhanced by free water diffusing into the sensor. This leads to a continuous hypsochromic shift of the absorption spectrum according to the water concetration. Another appropriate dye is 4-amino-N-methylphthalimid, which shows a similar behavior in its fluorescent spectra, and presently we are developing its derivatives and suitable polymer matrices. The determination of the pH-value of concrete is of major importance for the assessment of acidic attacks which may lead to serious damage in reinforced concrete, as the embedded steel structures exhibit long-term stability (i.e. resistance to corrosion) only at pH-values of 9 or higher. Therefore we have developed a fiberoptical sensor system for the measurement of pH-values in concrete consisting of pH- indicator dyes immobilized in a highly immobilized in a highly hydrophilic polymer matrix. Any change in pH-value of the wet concrete material is indicated by a color change of the dye/polymer system. The sensor system displays long term stability even in aggressive media of pH12 - 13.

  9. Magnetically remote-controlled optical sensor spheres for monitoring oxygen or pH.

    Science.gov (United States)

    Mistlberger, Günter; Koren, Klaus; Borisov, Sergey M; Klimant, Ingo

    2010-03-01

    Magnetic sensor macrospheres (MagSeMacs), i.e., stainless steel spheres coated with optical chemical sensors, are presented as an alternative to existing optical sensor patches and fiber-optical dip-probes. Such spheres can either be reversibly attached to the tip of an optical fiber (dip-probe) or trapped inside a vessel for read-out through the side wall. Moving the magnetic separator at the exterior enables measurements at varying positions with a single sensor. Moreover, the sensor's replacement is rapid and contactless. We measured dissolved oxygen or pH in stirred liquids, rotating flasks, and 24-well plates with a SensorDish-reader device for parallel cell culture monitoring. In these applications, MagSeMacs proved to be advantageous over conventional sensor patches and magnetic optical sensor particles because of their magnetism, spherical shape, reflectance, and size. These properties resulted in strong but reversible fixation, magnetic remote-controllability, short response times, high signal intensities, and simplified handling.

  10. Future changes in the Baltic Sea acid–base (pH and oxygen balances

    Directory of Open Access Journals (Sweden)

    Anders Omstedt

    2012-12-01

    Full Text Available Possible future changes in Baltic Sea acid–base (pH and oxygen balances were studied using a catchment–sea coupled model system and numerical experiments based on meteorological and hydrological forcing datasets and scenarios. By using objective statistical methods, climate runs for present climate conditions were examined and evaluated using Baltic Sea modelling. The results indicate that increased nutrient loads will not inhibit future Baltic Sea acidification; instead, the seasonal pH cycle will be amplified by increased biological production and mineralization. All examined scenarios indicate future acidification of the whole Baltic Sea that is insensitive to the chosen global climate model. The main factor controlling the direction and magnitude of future pH changes is atmospheric CO2 concentration (i.e. emissions. Climate change and land-derived changes (e.g. nutrient loads affect acidification mainly by altering the seasonal cycle and deep-water conditions. Apart from decreasing pH, we also project a decreased saturation state of calcium carbonate, decreased respiration index and increasing hypoxic area – all factors that will threaten the marine ecosystem. We demonstrate that substantial reductions in fossil-fuel burning are needed to minimise the coming pH decrease and that substantial reductions in nutrient loads are needed to reduce the coming increase in hypoxic and anoxic waters.

  11. Structural changes and relaxations monitored by luminescence.

    Science.gov (United States)

    Wang, Y; Yang, B; Townsend, P D

    2013-01-01

    Luminescence data have often been used to study imperfections and to characterize lattice distortions because the signals are sensitive to changes of structure and composition. Previous studies have included intentionally added probe ions such as rare earth ions to sense distortions in local crystal fields caused by modified structural environments. An under-exploited extension of this approach was to use luminescence to monitor crystalline phase changes. A current overview of this new and powerful technique shows that continuous scanning of the sample temperatures immediately offered at least three types of signatures for phase transitions. Because of high sensitivity, luminescence signals were equally responsive to structural changes from inclusions and nanoparticles. These coupled to the host material via long-range interactions and modified the host signals. Two frequently observed examples that are normally overlooked are from nanoparticle inclusions of water and CO2. Examples also indicated that phase transitions were detected in more diverse materials such as superconductors and fullerenes. Finally, luminescence studies have shown that in some crystalline examples, high dose ion implantation of surface layers could induce relaxations and/or structural changes of the entire underlying bulk material. This was an unexpected result and therefore such a possibility has not previously been explored. However, the implications for ion implication are significant and could be far more general than the examples mentioned here.

  12. Prospective molecular monitoring of BCR/ABL transcript in children with Ph+ acute lymphoblastic leukaemia unravels differences in treatment response.

    Science.gov (United States)

    Cazzaniga, Giovanni; Lanciotti, Marina; Rossi, Vincenzo; Di Martino, Daniela; Aricò, Maurizio; Valsecchi, Maria Grazia; Basso, Giuseppe; Masera, Giuseppe; Micalizzi, Concetta; Biondi, Andrea

    2002-11-01

    Children with Philadelphia-chromosome-positive (Ph+) acute lymphoblastic leukaemia (ALL) represent a subgroup at very high risk for treatment failure, despite intensive chemotherapy. However, recent retrospective studies showed that Ph+ childhood ALL is a heterogeneous disease with regard to treatment response. We have prospectively monitored, by reverse transcription polymerase chain reaction (RT-PCR) during follow-up, the presence of the BCR/ABL fusion transcript in Ph+ ALL children diagnosed in the Italian multicentre Associazione Italiana Ematologia Oncologia Pediatrica ALL-AIEOP-95 therapy protocol. To our knowledge, this is the first report on the evaluation of minimal residual disease (MRD) in childhood Ph+ ALL prospectively enrolled in an intensive, Berlin-Frankfurt-Munster (BFM)-type treatment protocol. Twenty-seven of 36 (75.0%) Ph+ patients consecutively enrolled into the high-risk group of the AIEOP-ALL protocol between May 1995 and October 1999 were successfully analysed. Twenty were good responders to the pre-phase of prednisone/intrathecal methotrexate treatment (PGR) and seven were poor responders (PPR). Within the PPR group, the RT-PCR monitoring constantly showed positivity for the BCR/ABL fusion transcript and all the patients died of disease progression. In contrast, highly sensitive qualitative RT-PCR monitoring revealed heterogeneity within the PGR group of Ph+ childhood ALL patients. Three different subgroups could be defined, according to the clearance of Ph+ cells within the first 5 months of treatment. This provides useful information on the capability of chemotherapy to reduce the leukaemic clone, with prognostic implications.

  13. Role of PH Monitoring in Laryngopharyngeal Reflux Patients with Voice Disorders

    Science.gov (United States)

    Maldhure, Swati; Chandrasekharan, Ramanathan; Dutta, Amit- Kumar; Chacko, Ashok; Kurien, Mary

    2016-01-01

    Introduction: Laryngopharyngeal reflux (LPR) is considered an important cause of voice disorder. We aimed to determine the frequency of LPR in patients with voice disorder and the association between Koufman Reflux Symptom Index (RSI), Reflux Finding Score (RFS), gastroesophageal reflux disease (GERD), and proximal acid reflux in these patients. Materials and Methods: We performed a prospective study in patients aged more than 18 years presenting at the ear, nose, and throat (ENT) clinic with a change in voice lasting more than 3 weeks. All patients underwent nasopharyngolaryngoscopy and a dual-probe esophageal pH study. LPR was diagnosed by a Koufman RSI of >13 and/or RFS of >7. GERD was diagnosed according to a DeMeester Johnson score of >14.7. Proximal acid reflux was diagnosed if acid exposure time was >0.02% in a proximal pH probe. Results: The study included 30 patients with a voice disorder. The mean age of participants was 38.5 years and 40% of patients were female. Using either of the two criteria, LPR was present in 46.7% of patients, half of whom had GERD. Among the remaining 53.3% patients with a voice disorder and no evidence of LPR, GERD was present in 25%. There was no significant association between the presence of LPR based on RSI (P=1) and GERD or RFS and GERD (P=0.06). Proximal acid reflux was present in only 10% patients with a voice disorder, and there was no significant association of this test with RFS (P=1) or RSI (P=1). Conclusions: Approximately half of the patients with a voice disorder have LPR, and only a subset of these patients have evidence of GERD. Fiberoptic laryngoscopic findings (RFS) complementing RSI appears to be important in diagnosing possible reflux etiology in voice disorders and can be an indicator for instituting anti-reflux therapy. However, there is no significant association between RSI, RFS, and GERD suggesting that these tests evaluate different features of the disease. Proximal acid reflux is uncommon in patients

  14. Colour and pH changes of tempe during extended fermentation

    Science.gov (United States)

    Muzdalifah, D.; Athaillah, Z. A.; Nugrahani, W.; Devi, A. F.

    2017-01-01

    Tempe is a nutritious food, prepared mostly from soybeans and was originated in Indonesia. Tempe is sometimes collected beyond its maturity age for culinary purpose. The studies of overripe tempe ranged from microbiology, chemical and nutritional changes, functionality and safety, to sensorial aspect. Study which follows pH and colour changes of tempe during fermentation, however, is scarce. The objectives of this study were to investigate and model the colour and pH changes of tempe and the mould mycelia during extended fermentation with Rhizopus spp. up to 156 hours. Our investigation revealed that both lightness soybeans and mycelia of the tempe decreased with increasing fermentation time while pH of the tempe increased. The decrease of both lightness followed simple cubic equations whilst the pH increased linearly with increasing time. The other a values of tempe decreased by one point in the first 72 h of fermentation and tended to increase later however did not reach the initial a value, The b value decreased by approximately two points during the first 24 h of fermentation and the changes during the rest of fermentation time were not significant. The colour changes were believed to be the results of increased numbers of Rhizopus spp which entered the death phase, increased amount of linoleic and linolenic unsaturated fatty acids which were prone to oxidation, and formation of red coloured vitamin B12. Meanwhile, the increase of pH was majorly because of protein break down which led to increased ammonia production. The utilisation of lactic acid for mould growth also contributed to the alkalinisation, however to a much lesser extent. The lactic acid was previously formed during the soaking which resulted in decrease in pH of initial soybeans.

  15. Reduction of intracellular pH by tenidap. Involvement of cellular anion transporters in the pH change.

    Science.gov (United States)

    McNiff, P; Robinson, R P; Gabel, C A

    1995-10-26

    Tenidap [5-chloro-2,3-dihydro-3-(hydroxy-2-thienylmethylene)-2-oxo-1H- indole-1-carboxamide], a novel antirheumatic agent, produces a rapid and sustained intracellular acidification when applied to cells in culture. To investigate the mechanism by which this change in ionic homeostasis is achieved, the acidification activities of structural analogs of tenidap were determined, and the movements of [14C]tenidap into and out of cells were explored. The acidification activity of tenidap was enhanced by lowering extracellular pH, suggesting that the free acid species was required for this process. Consistent with this requirement, a non-acidic analog of tenidap did not produce a change in intracellular pH (pHi). In contrast, multihalogenated derivatives of tenidap produced greater changes in pHi than did tenidap, and one analog produced a transient acidification from which the cell recovered; this recovery, however, was blocked by an inhibitor of the Na+/H+ antiporter. Fibroblasts incubated with [14C]tenidap achieved within 5 min a level of cell-associated drug that remained constant during longer incubations. Simultaneous addition of the electrogenic ionophore valinomycin or the P-glycoprotein inhibitor 4-(3,4-dihydro-6,7-dimethoxy-2(1H)-isoquinolinyl)-N-[2-(3,4-dimethoxyphe nyl) ethyl]-6,7-dimethoxy-2-quinazolinamine (CP-100,356) caused a time- and concentration-dependent increase in the level of cell-associated [14C]tenidap; other agents tested did not promote this enhanced cellular accumulation. [14C]Tenidap accumulated by fibroblasts in the presence of CP-100,356 subsequently was released when these cells were placed in a tenidap- and CP-100,356-free medium. Importantly, several agents that are known to inhibit anion transport processes, including alpha-cyano-beta-(1-phenylindol-3-yl) acrylate, 5-nitro-2(3-phenylpropylamino)-benzoic acid, and meclofenamic acid, inhibited efflux of [14C]tenidap. In contrast, ethacrynic acid and 4,4'-diisothiocyanatostilbene-2

  16. Native and introduced clams biochemical responses to salinity and pH changes.

    Science.gov (United States)

    Velez, Catia; Figueira, Etelvina; Soares, Amadeu M V M; Freitas, Rosa

    2016-10-01

    By the end of year 2100 physiological and biochemical performance of aquatic organisms are expected to become strongly affected by salinity and pH shifts, which in turn may favor the conditions for introduced species to invade new ecosystem areas. Given this, we evaluated the effects of salinity and pH changes in native Ruditapes decussatus and introduced Ruditapes philippinarum clams, by measuring different biomarkers related to oxidative stress, metabolic activity and osmoregulation capacity. Results showed that extreme salinities induced mortality in both species, while all clams survived under low pH (7.3). Both species mobilized glycogen as a source of energy towards cells protection mechanisms under extreme salinities. The native species presented higher lipid peroxidation levels while the introduced species was able to prevent oxidative damages through the induction of antioxidant enzymes at most extreme salinities. R. philippinarum also induced CA activity to balance the ion homeostasis at extreme salinities. In contrast, low pH induced oxidative damages, an increase of antioxidant (catalase), detoxification (glutathione S-transferases) and osmoregulation (carbonic anhydrase) mechanisms in R. philippinarum compared to the native clams. Overall, salinity and pH changes can alter physiological and biochemical status of native and introduced clam species. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Generalised expressions for the response of pH to changes in ocean chemistry

    NARCIS (Netherlands)

    Hagens, M.; Middelburg, J.B.M.

    2016-01-01

    The extent to which oceans are capable of buffering chemical changes resulting from the uptake of carbon dioxide (CO2) or other acidifying processes can be quantified using buffer factors. Here, we present general expressions describing the sensitivity of pH and concentrations of CO2 and other acid–

  18. Early monitoring of PtiO2, PtiCO2, pH and brain temperat ure in patients with brain injuries and the clinical significanc e

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To explore the regulation of early br ain tissue metabolic changing after brain injuries and the clinical significance .   Methods: There were 17 patients with brain injuries. Early dire ct monitoring of PtiO2, PtiCO2, pH and brain temperature, dynami c observation of the relation between various parameters and clinics after brai n injuries were performed.   Results: Early changes of PtiO2, PtiCO2 and pH we re closely correlated with outcome. The death rate obviously increased when P tiO2 was continuously lower than 9 mm?Hg within 24 hours after injuries. Secondary brain injury prolonged and aggravated brain tissue metabolic disturban ce. When intracerebral pressure was over 30 mm?Hg PtiO2 began to de crea se. The brain temperature in brain death patients was evidently lower than axill ary temperature.   Conclusions: The direct monitoring of PtiO2, PtiC O2, pH and brain temperature is safe and accurate and can find early anoxia da mage to brain tissue and provide reliable basis for clinical therapy. It ha s an instructive significance in selecting and studying a new treatment method i n brain injuries. And it can be taken as a criterion in clinical judging brain d eaths.

  19. The LHC Fast Beam Current change Monitor

    CERN Document Server

    Belohrad, D; Jensen, L; Krupa, M; Topaloudis, A

    2013-01-01

    The modularity of the Large Hadron Collider’s (LHC) machine protection system (MPS) allows for the integration of several beam diagnostic instruments. These instruments have not necessarily been designed to have protection functionality, but MPS can still use them to increase the redundancy and reliability of the machine. The LHC fast beam current change monitor (FBCCM) is an example. It is based on analogue signals from fast beam current transformers (FBCT) used nominally to measure the LHC bunch intensities. The FBCCM calculates the magnitude of the beam signal provided by the FBCT, looks for a change over specific time intervals, and triggers a beam dump interlock if losses exceed an energy-dependent threshold. The first prototype of the FBCCM was installed in the LHC during the 2012-2013 run. The aim of this article is to present the FBCCM system and the results obtained, analyse its current performance and provide an outlook for the final system which is expected to be operational after the long LHC sh...

  20. Monitoring changes in hemodynamics following optogenetic stimulation

    Science.gov (United States)

    Frye, Seth

    The brain is composed of billions of neurons, all of which connected through a vast network. After years of study and applications of different technologies and techniques, there are still more questions than answers when it comes to the fundamental functions of the brain. This project aims to provide a new tool which can be used to gain a better understanding of the fundamental mechanisms that govern neurological processes inside the brain. In order for neural networks to operate, blood has to be supplied through neighboring blood vessels. As such, the increase or decrease in the blood supply has been used as an indicator of neural activity. The neural activity and blood supply relationship is known as neural vasculature coupling. Monitoring the hemodynamics is used as an indicator of neurological activity, but the causal relationship is an area of current research. Gaining a better understanding of the coupling of neural activity and the surrounding vasculature provides a more accurate methodology to evaluate regional neural activity. The new optical technology applied in this project provides a set of tools to both stimulate and monitor this coupling relationship. Optogenetics provides the capability of stimulating neural activity using specific wavelengths of light. Essentially this tool allows for the direct stimulation of networks of neurons by simply shining one color of light onto the brain. Optical Coherence Tomography (OCT), another new optical technology applied in this project, can record volumetric images of blood vessels and flow using only infrared light. The combination of the two optical technologies is then capable of stimulating neural activity and monitoring the hemodynamic response inside the brain using only light. As a result of this project we have successfully demonstrated the capability of both stimulating and imaging the brain using new optical technologies. The optical stimulation of neural activity has evoked a direct hemodynamic effect

  1. NAADP induces pH changes in the lumen of acidic Ca2+ stores

    OpenAIRE

    2006-01-01

    Abstract NAADP-induced Ca 2+} release has been proposed to occur selectively from acidic stores in several cell types including sea urchin eggs. Using fluorescence measurements, we have investigated whether NAADP-induced Ca 2+} release alters the luminal pH (pHL) within these acidic stores in egg homogenates and observed their prompt, concentration-dependent alkalinization by NAADP (but not {beta}-NAD +} or NADP). Like Ca 2+} release, the pH L} change was desensitized by low concen...

  2. Electroporation on microchips: the harmful effects of pH changes and scaling down.

    Science.gov (United States)

    Li, Yang; Wu, Mengxi; Zhao, Deyao; Wei, Zewen; Zhong, Wenfeng; Wang, Xiaoxia; Liang, Zicai; Li, Zhihong

    2015-12-14

    Electroporation has been widely used in delivering foreign biomolecules into cells, but there is still much room for improvement, such as cell viability and integrity. In this manuscript, we investigate the distribution and the toxicity of pH changes during electroporation, which significantly decreases cell viability. A localized pH gradient forms between anode and cathode leading to a localized distribution of cell death near the electrodes, especially cathodes. The toxicity of hydroxyl ions is severe and acute due to their effect in the decomposition of phospholipid bilayer membrane. On the other hand, the electric field used for electroporation aggravates the toxicity of hydroxyl because the electropermeabilization of cell membrane makes bilayer structure more loosen and vulnerable. We also investigate the side effects during scaling down the size of electrodes in electroporation microchips. Higher percentage of cells is damaged when the size of electrodes is smaller. At last, we propose an effective strategy to constrain the change of pH by modifying the composition of electroporation buffer. The modified buffer decreases the changes of pH, thus enables high cell viability even when the electric pulse duration exceeds several milliseconds. This ability has potential advantage in some applications that require long-time electric pulse stimulation.

  3. Changes in PaO2 and pH in experimental hepatocarcinoma

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    AIM: To study the changes in PaO2 and pH in experimental hepatocarcinoma and their significance.METHODS:Qualitative analysis of the PaO2 and pH was made by three channel tissue measuring equipment in experimental hepatocarcinoma and comparative liver tissue. RESULTS:The results showed that the PaO2 in tissue of test group was significantly higher than that of control group (P<0.01), but the pH of tissue in test group was slight higher than that of control group (P>0.05).CONCLUSION: PaO2 might play an impontant in genesis and developmant of hepatocarcinoma. PaO2 may be helpful in diagnosis and differentiated diagnosis for hepatocarcinoma.

  4. Bringing New Ph.D.s Together for Interdisciplinary Climate Change Research

    Science.gov (United States)

    Phelan, Liam; Jones, Holly; Marlon, Jennifer R.

    2013-01-01

    Climate change is complex and thus requires interdisciplinary research, and new scholars are rising to that challenge. The Dissertations Initiative for the Advancement of Climate Change Research (DISCCRS (pronounced "discourse"); see http://www.disccrs.org) brings together select groups of recent PhD graduates to encourage interdisciplinary work on climate change. The DISCCRS Symposium VII held just outside of Colorado Springs, Colo., brought together 33 graduates from fields as diverse as climatology, ecology, anthropology, and political science for an intensive week of cross-disciplinary engagement in activities like facilitation and leadership training, collaborative research development, peer networking, communication training, and analysis of working group processes.

  5. Monitoring of Physicochemical Changes in Frozen Fish Muscle Tissue

    Directory of Open Access Journals (Sweden)

    František Ježek

    2011-10-01

    Full Text Available The aim of the study was to monitor physicochemical parameters (pH, nitrogen trimethylamine N-TMA, total volatile basic nitrogen TVBN, free fatty acids FFA, peroxide value and thiobarbituric acid assay TBA of postmortal changes in muscle tissue of silver carp (Hypophthalmichthys molitrix during a period of storage at -18°C. Fresh silver carp samples and samples aft er three, six, nine and 12 months of storage were tested. The degree of acidification during the experiment was insignificant (P > 0.05. Proteolytic changes were almost stopped and TVBN levels remained unchanged (P > 0.05, while N-TMA levels fluctuated significantly (P < 0.01 between months 3 and 12. The essential were lipid hydrolysis and oxidation, which caused a significant increase in FFA values (5.89 ± 0.99% total lipids as oleic acid, peroxides (9.90 ± 2.83 mekv O2.kg-1 and TBA values (50.76 ± 31.52 mg MDA.kg-1. The shelf life recommended for silver carp was set at three months.

  6. Monitoring of Physicochemical Changes in Frozen Fish Muscle Tissue

    Directory of Open Access Journals (Sweden)

    František Ježek

    2011-09-01

    Full Text Available The aim of the study was to monitor physicochemical parameters (pH, nitrogen trimethylamine N-TMA, total volatile basic nitrogen TVBN, free fatty acids FFA, peroxide value and thiobarbituric acid assay TBA of postmortal changes in muscle tissue of silver carp (Hypophthalmichthys molitrix during a period of storage at -18°C. Fresh silver carp samples and samples aft er three, six, nine and 12 months of storage were tested. The degree of acidification during the experiment was insignificant (P > 0.05. Proteolytic changes were almost stopped and TVBN levels remained unchanged (P > 0.05, while N-TMA levels fluctuated significantly (P < 0.01 between months 3 and 12. The essential were lipid hydrolysis and oxidation, which caused a significant increase in FFA values (5.89 ± 0.99% total lipids as oleic acid, peroxides (9.90 ± 2.83 mekv O2.kg-1 and TBA values (50.76 ± 31.52 mg MDA.kg-1. The shelf life recommended for silver carp was set at three months.

  7. Generalised expressions for the response of pH to changes in ocean chemistry

    Science.gov (United States)

    Hagens, Mathilde; Middelburg, Jack J.

    2016-08-01

    The extent to which oceans are capable of buffering chemical changes resulting from the uptake of carbon dioxide (CO2) or other acidifying processes can be quantified using buffer factors. Here, we present general expressions describing the sensitivity of pH and concentrations of CO2 and other acid-base species to a change in ocean chemistry. These expressions can include as many acid-base systems as desirable, making them suitable for application to, e.g., upwelling regions or nutrient-rich coastal waters. We show that these expressions are fully consistent with previously derived expressions for the Revelle factor and other buffer factors, which only included the carbonate and borate acid-base systems, and provide more accurate values. We apply our general expressions to contemporary global ocean surface water and possible changes therein by the end of the 21st century. These results show that most sensitivities describing a change in pH are of greater magnitude in a warmer, high-CO2 ocean, indicating a decreased seawater buffering capacity. This trend is driven by the increase in CO2 and slightly moderated by the warming. Respiration-derived carbon dioxide may amplify or attenuate ocean acidification due to rising atmospheric CO2, depending on their relative importance. Our work highlights that, to gain further insight into current and future pH dynamics, it is crucial to properly quantify the various concurrently acting buffering mechanisms.

  8. Relationship between nasolaryngoscopic findings and pH probe esophageal monitoring in children with clinical manifestations of extra-esophageal reflux

    Directory of Open Access Journals (Sweden)

    Oliveira, Neide Fatima Cordeiro Diniz

    2009-06-01

    Full Text Available Introduction: The gastroesophageal reflux diagnosis, mainly in patients with atypical manifestations, has been receiving increasing importance. Objective: To relate the nasolaryngoscopic findings with prolonged pH probe esophageal monitoring in children with clinical manifestations of extra-esophageal reflux. Method: Transversal prospective clinical study, in which we evaluated 44 children from one to 12 years old, of both genders, by means of nasolaryngoscopy. All were submitted to pH probe monitoring for research of hidden reflux due to cases of otitis, sinusitis, asthma, laryngitis and/or dysphonia in the last 12 months. Results: Out of 44 children, 15 (34% presented with normal pH monitoring and 29 (66% with altered monitoring. Out of 29 with altered pH monitoring, 19 (65.5% were boys and 10 (34.5% were girls. There was no statistically significant difference between gender and the positive results of pH monitoring, in spite of a discreet predominance of occurrence in the male population. All children had smaller adenoids than 75% of the cavity of concha aerial column. Six presented with purulent secretion in nasal cavity. Eight (18% had nodes in vocal cords and five (11% of whom had an altered pH monitoring and three (7% of whom were normal. We found at least one alteration upon nasolaryngoscopy in 80% of the 15 children with normal pH monitoring and in 89.7% of the 29 who had an altered pH monitoring. Conclusion: The prevalence of gastroesophageal reflux in children with recurrent respiratory and otorhinolaryngological affections was high. However, the data obtained didn't show any statistically significant difference (p<0.05 among the nasolaryngoscopic findings, associated or not with gastroesophageal reflux, confirmed by pH monitoring. Therefore, no relationship was found between the pathological gastric acid reflux and nasolaryngoscopic alterations.

  9. Manipulating and Monitoring On-Surface Biological Reactions by Light-Triggered Local pH Alterations.

    Science.gov (United States)

    Peretz-Soroka, Hagit; Pevzner, Alexander; Davidi, Guy; Naddaka, Vladimir; Kwiat, Moria; Huppert, Dan; Patolsky, Fernando

    2015-07-08

    Significant research efforts have been dedicated to the integration of biological species with electronic elements to yield smart bioelectronic devices. The integration of DNA, proteins, and whole living cells and tissues with electronic devices has been developed into numerous intriguing applications. In particular, the quantitative detection of biological species and monitoring of biological processes are both critical to numerous areas of medical and life sciences. Nevertheless, most current approaches merely focus on the "monitoring" of chemical processes taking place on the sensing surfaces, and little efforts have been invested in the conception of sensitive devices that can simultaneously "control" and "monitor" chemical and biological reactions by the application of on-surface reversible stimuli. Here, we demonstrate the light-controlled fine modulation of surface pH by the use of photoactive molecularly modified nanomaterials. Through the use of nanowire-based FET devices, we showed the capability of modulating the on-surface pH, by intensity-controlled light stimulus. This allowed us simultaneously and locally to control and monitor pH-sensitive biological reactions on the nanodevices surfaces, such as the local activation and inhibition of proteolytic enzymatic processes, as well as dissociation of antigen-antibody binding interactions. The demonstrated capability of locally modulating the on-surface effective pH, by a light stimuli, may be further applied in the local control of on-surface DNA hybridization/dehybridization processes, activation or inhibition of living cells processes, local switching of cellular function, local photoactivation of neuronal networks with single cell resolution and so forth.

  10. Monitoring of extracellular pH in young dental biofilms grown in situ in the presence and absence of sucrose

    DEFF Research Database (Denmark)

    Dige, Irene; Bælum, Vibeke; Schlafer, Sebastian;

    biofilms. Fluorescence emissions of C-SNARF-4 in deep layers of each biofilm were recorded ex-vivo with confocal microscopy for 15 min (3 sites) or for 1 h (6 sites) after exposure to a 100 µl salivary solution with 0.4% glucose in custom-made wells. The ratiometric pH data were analyzed using a mixed......pH in dental biofilms is of central importance for the development of caries. We used the ratiometric pH-sensitive dye C-SNARF-4 in combination with digital image analysis to monitor extracellular pH in dental biofilms grown in situ with and without sucrose supply. 48-h dental biofilms from 10......-effects linear regression procedure. Extracellular pH dropped rapidly in most examined sites after addition of glucose. Distinct pH microenvironments were observed within single biofilms. Variance components analyses showed similar variation between sites within the same biofilm (var=0.02-0.04 (se=0...

  11. Cytoplasmic pH dynamics in maize pulvinal cells induced by gravity vector changes

    Science.gov (United States)

    Johannes, E.; Collings, D. A.; Rink, J. C.; Allen, N. S.; Brown, C. S. (Principal Investigator)

    2001-01-01

    In maize (Zea mays) and other grasses, changes in orientation of stems are perceived by pulvinal tissue, which responds to the stimulus by differential growth resulting in upward bending of the stem. The amyloplast-containing bundle sheath cells are the sites of gravity perception, although the initial steps of gravity perception and transmission remain unclear. In columella cells of Arabidopsis roots, we previously found that cytoplasmic pH (pH(c)) is a mediator in early gravitropic signaling (A.C. Scott, N.S. Allen [1999] Plant Physiol 121: 1291-1298). The question arises whether pH(c) has a more general role in signaling gravity vector changes. Using confocal ratiometric imaging and the fluorescent pH indicator carboxy seminaphtorhodafluor acetoxymethyl ester acetate, we measured pH(c) in the cells composing the maize pulvinus. When stem slices were gravistimulated and imaged on a horizontally mounted confocal microscope, pH(c) changes were only apparent within the bundle sheath cells, and not in the parenchyma cells. After turning, cytoplasmic acidification was observed at the sides of the cells, whereas the cytoplasm at the base of the cells where plastids slowly accumulated became more basic. These changes were most apparent in cells exhibiting net amyloplast sedimentation. Parenchyma cells and isolated bundle sheath cells did not show any gravity-induced pH(c) changes although all cell types responded to external stimuli in the predicted way: Propionic acid and auxin treatments induced acidification, whereas raising the external pH caused alkalinization. The results suggest that pH(c) has an important role in the early signaling pathways of maize stem gravitropism.

  12. Role of a Transbilayer pH Gradient in the Membrane Fusion Activity of the Influenza Virus Hemagglutinin: Use of the R18 Assay to Monitor Membrane Merging

    Directory of Open Access Journals (Sweden)

    Pedroso de Lima Maria C.

    1999-01-01

    Full Text Available It had been suggested that influenza virus-mediated membrane fusion might be dependent on a pH gradient across a target membrane. We have designed experiments in which this issue could be addressed. Two populations of liposomes were prepared, both simulating the plasma membrane of target cells, but with the pH of the internal aqueous medium buffered either at pH 7.4 (physiological cytosol pH or at pH 5.0 (endosomal pH at which influenza virus displays maximal fusion activity. By monitoring fusion using the R18 assay, we found that the internal pH of the target liposomes did not influence membrane merging as mediated by the influenza virus hemagglutinin, thus demonstrating that a transmembrane pH gradient is not required in this fusion process.

  13. Role of a Transbilayer pH Gradient in the Membrane Fusion Activity of the Influenza Virus Hemagglutinin: Use of the R18 Assay to Monitor Membrane Merging.

    Science.gov (United States)

    Ramalho-Santos, João; Pedroso De Lima, Maria C.

    1999-03-16

    It had been suggested that influenza virus-mediated membrane fusion might be dependent on a pH gradient across a target membrane. We have designed experiments in which this issue could be addressed. Two populations of liposomes were prepared, both simulating the plasma membrane of target cells, but with the pH of the internal aqueous medium buffered either at pH 7.4 (physiological cytosol pH) or at pH 5.0 (endosomal pH at which influenza virus displays maximal fusion activity). By monitoring fusion using the R18 assay, we found that the internal pH of the target liposomes did not influence membrane merging as mediated by the influenza virus hemagglutinin, thus demonstrating that a transmembrane pH gradient is not required in this fusion process.

  14. The pH dependence of phototautomerism in horse radish peroxidase monitored by fluorescence site-selection spectroscopy

    Science.gov (United States)

    Fidy, Judit; Koloczek, Henryk; Paul, Karl-Gustav; Vanderkooi, Jane M.

    1987-12-01

    Fluorescence site-selection spectra of mesoporphyrin horse radish peroxidase C 2 were measured at cryogenic temperatures in 50% glycerol-water. With irradiation at ≈ 17300 cm -1 interconverting emission lines were detected, which are attributed to phototautomerization within the excited sites. The reactivity for tautomerization was found to be much higher at pH 5.1 than at pH 8.0. The fluorescence decay for the two tautomers is single exponential with lifetimes of 23 and 21 ns, respectively. pH sensitivity is discussed in terms of possible conformational changes of the amino acid chain or a role of the liberated histidine in the reaction pathway.

  15. [Ambulatory esophageal pH monitoring: critical review of methodology: (equipment, reproducibility, standards), clinical importance and personal experience].

    Science.gov (United States)

    Jonard, P; Fiasse, R; Tomé, G; Dive, C

    1990-01-01

    The authors review the recent literature about the methodology of oesophageal pH monitoring, which has a high sensitivity and a high specificity for assessing gastro-oesophageal reflux. Combined electrodes offer most advantages. Ambulatory recording should be done in hospital under standard conditions (meals), particularly for clinical studies. The best clinical indication is to detect pathological reflux in case of atypical symptoms with negative oesophagoscopy. The authors give their normal values in a series of measurements with two systems as well as their results in a series of cases of oesophagitis of various grades.

  16. Monitoring adaptive genetic responses to environmental change

    DEFF Research Database (Denmark)

    Hansen, M.M.; Olivieri, I.; Waller, D.M.

    2012-01-01

    Widespread environmental changes including climate change, selective harvesting and landscape alterations now greatly affect selection regimes for most organisms. How animals and plants can adapt to these altered environments via contemporary evolution is thus of strong interest. We discuss how...... for selection and establishing clear links between genetic and environmental change. We then review a few exemplary studies that explore adaptive responses to climate change in Drosophila, selective responses to hunting and fishing, and contemporary evolution in Daphnia using resurrected resting eggs. We...

  17. Histologic changes of doxycycline pleurodesis in rabbits. Effect of concentration and pH.

    Science.gov (United States)

    Hurewitz, A N; Lidonicci, K; Wu, C L; Reim, D; Zucker, S

    1994-10-01

    The effects of doxycycline hyclate (DOXY) pleurodesis were compared with those of tetracycline hydrochloride (TCN) in 25 healthy New Zealand White rabbits. One group of rabbits received TCN (pH 2.0) in the left pleural space at a concentration of 35 mg/kg in 3.0 ml of saline solution. Four other groups of rabbits received DOXY in two concentrations (35 mg/kg or 10 mg/kg) and at two pHs (an acid of 2.0 and a NaOH neutralized pH of 7.6). No attempt was made to drain the pleural space after pleurodesis. At autopsy 2 weeks later, bloody fluid filled the pleural cavity and extensive intrapleural adhesions compressed the underlying lung. Microscopically, fibrin and collagen were diffusely deposited in the pleural connective tissue and in the intrapleural adhesions. The visceral pleural thickness increased from its normal value of 0.01 mm to values of 0.5 to 0.9 mm in the TCN and DOXY groups. Fibroblasts were the predominant inflammatory cell in the pleural connective tissue with few neutrophils or lymphocytes. No significant differences of histologic characteristics were observed between the TCN and DOXY groups. Alterations in pH or concentration in the DOXY groups produced similar changes in the gross and microscopic appearance of the pleural space. We conclude that DOXY is as effective as TCN in producing chemical pleurodesis. Doxycycline concentrations of 10 mg/kg were sufficient to substantially sclerose the pleural space in these healthy rabbits. Doxycycline pleurodesis was effective at neutral pH suggesting a mechanism of action independent of acid injury to the mesothelium.

  18. Monitoring global change: a selection of examples

    CSIR Research Space (South Africa)

    CSIR, Natural Resources and Environment

    2008-02-01

    Full Text Available forecasts of changes in weather patterns over the next few days have reached a high level of skill, predictions of climatic fluctuations over several months and of global climate changes over several decades are difficult due to the very complex interaction...

  19. Orbital monitoring of martian surface changes

    Science.gov (United States)

    Geissler, Paul E.; Fenton, Lori K.; Enga, Marie-therese; Mukherjee, Priyanjoli

    2016-11-01

    A history of martian surface changes is documented by a sequence of global mosaics made up of Mars Global Surveyor Mars Orbiter Camera daily color images from 1999 to 2006, together with a single mosaic from the Mars Reconnaissance Orbiter Mars Color Imager in 2009. These observations show that changes in the global albedo patterns of Mars take place by a combination of dust storms and strong winds. Many of the observed surface changes took place along the tracks of seasonally repeating winter dust storms cataloged by Wang and Richardson (2015). These storms tend to sweep dust towards the equator, progressively shifting albedo boundaries and continuing surface changes that began before the arrival of MGS. The largest and most conspicuous changes took place during the global dust storm of 2001 (MY 25), which blanketed Syrtis Major, stripped dust from the Tharsis region, and injected dust into Solis Planum. High wind speeds but low wind stresses are predicted in Syrtis, Tharsis and Solis by the NASA Ames GCM. Frequent changes in these regions show that dust accumulations are quickly removed by stronger winds that are not predicted by the GCM, but may result from smaller-scale influences such as unresolved topography.

  20. MONITORING THE SPECIATION OF AQUEOUS FREE CHLORINE FROM PH 1-12 WITH RAMAN SPECTROSCOPY TO DETERMINE THE IDENTITY OF THE POTENT LOW-PH OXIDANT

    Science.gov (United States)

    The speciation of aqueous free chlorine above pH 5 is a well-understood equilibrium of H2O + HOCl (equilibrium) OCl- + H3O+ with a pKa of 7.5. However, the identity of another very potent oxidant present at low pH (below 5) has been attributed by some researchers to Cl2 (aq), a...

  1. Effect of glycine on pH changes and protein stability during freeze-thawing in phosphate buffer systems.

    Science.gov (United States)

    Pikal-Cleland, Katherine A; Cleland, Jeffrey L; Anchordoquy, Thomas J; Carpenter, John F

    2002-09-01

    Previous studies have established that the selective precipitation of a less soluble buffer component during freezing can induce a significant pH shift in the freeze concentrate. During freezing of sodium phosphate solutions, crystallization of the disodium salt can produce a pH decrease as great as 3 pH units which can dramatically affect protein stability. The objective of our study was to determine how the presence of glycine (0-500 mM), a commonly used bulking agent in pharmaceutical protein formulations, affects the pH changes normally observed during freezing in sodium phosphate buffer solutions and to determine whether these pH changes contribute to instability of model proteins in glycine/phosphate formulations. During freezing in sodium phosphate buffers, the presence of glycine significantly influenced the pH. Glycine at the lower concentrations (phosphate buffer, possibly by reducing the nucleation rate of salt and thereby decreasing the extent of buffer salt crystallization. The presence of glycine at higher concentration (> 100 mM) in the sodium phosphate buffer resulted in a more complete crystallization of the disodium salt as indicated by the frozen pH values closer to the equilibrium value (pH 3.6). Although high concentrations of glycine can facilitate more buffer salt crystallization and these pH shifts may prove to be potentially damaging to the protein, glycine, in its amorphous state, can also act to stabilize a protein via the preferential exclusion mechanism.

  2. Characterization of Local pH Changes in Brain Using Fast-Scan Cyclic Voltammetry with Carbon Microelectrodes

    Science.gov (United States)

    Takmakov, Pavel; Zachek, Matthew K.; Keithley, Richard B.; Bucher, Elizabeth; McCarty, Gregory S.; Wightman, R. Mark

    2010-01-01

    Transient local pH changes in the brain are important markers of neural activity that can be used to follow metabolic processes that underlie the biological basis of behavior, learning and memory. There are few methods that can measure pH fluctuations with sufficient time resolution in freely moving animals. Previously, fast-scan cyclic voltammetry at carbon-fiber microelectrodes was used for the measurement of such pH transients. However, the origin of the potential dependent current in the cyclic voltammograms for pH changes recorded in vivo was unclear. The current work explored the nature of these peaks and established the origin for some of them. A peak relating to the capacitive nature of the pH CV was identified. Adsorption of electrochemically inert species, such as aromatic amines and calcium could suppress this peak, and is the origin for inconsistencies regarding in vivo and in vitro data. Also, we identified an extra peak in the in vivo pH CV relating to the presence of 3,4-dihydroxyacetic acid (DOPAC) in the brain extracellular fluid. To evaluate the in vivo performance of the carbon-fiber sensor, carbon dioxide inhalation by an anesthetized rat was used to induce brain acidosis induced by hypercapnia. Hypercapnia is demonstrated to be a useful tool to induce robust in vivo pH changes, allowing confirmation of the pH signal observed with FSCV. PMID:21047096

  3. Intracellular pH homeostasis and serotonin-induced pH changes in Calliphora salivary glands: the contribution of V-ATPase and carbonic anhydrase.

    Science.gov (United States)

    Schewe, Bettina; Schmälzlin, Elmar; Walz, Bernd

    2008-03-01

    Blowfly salivary gland cells have a vacuolar-type H(+)-ATPase (V-ATPase) in their apical membrane that energizes secretion of a KCl-rich saliva upon stimulation with serotonin (5-hydroxytryptamine, 5-HT). We have used BCECF to study microfluometrically whether V-ATPase and carbonic anhydrase (CA) are involved in intracellular pH (pH(i)) regulation, and we have localized CA activity by histochemistry. We show: (1) mean pH(i) in salivary gland cells is 7.5+/-0.3 pH units (N=96), higher than that expected from passive H(+) distribution; (2) low 5-HT concentrations (0.3-3 nmol l(-1)) induce a dose-dependent acidification of up to 0.2 pH units, with 5-HT concentrations >10 nmol l(-1), causing monophasic or multiphasic pH changes; (3) the acidifying effect of 5-HT is mimicked by bath application of cAMP, forskolin or IBMX; (4) salivary gland cells exhibit CA activity; (5) CA inhibition with acetazolamide and V-ATPase inhibition with concanamycin A lead to a slow acidification of steady-state pH(i); (6) 5-HT stimuli in the presence of acetazolamide induce an alkalinization that can be decreased by simultaneous application of the V-ATPase inhibitor concanamycin A; (7) concanamycin A removes alkali-going components from multiphasic 5-HT-induced pH changes; (8) NHE activity and a Cl(-)-dependent process are involved in generating 5-HT-induced pH changes; (9) the salivary glands probably contain a Na(+)-driven amino acid transporter. We conclude that V-ATPase and CA contribute to steady-state pH(i) regulation and 5-HT-induced outward H(+) pumping does not cause an alkalinization of pH(i) because of cytosolic H(+) accumulation attributable to stimulated cellular respiration and AE activity, masking the alkalizing effect of V-ATPase-mediated acid extrusion.

  4. The biokarst system and its carbon sinks in response to pH changes: A simulation experiment with microalgae

    Science.gov (United States)

    Xie, Tengxiang; Wu, Yanyou

    2017-03-01

    This study aims to explore the changes in a microalgal biokarst system as a potential carbon sink system in response to pH changes. The bidirectional isotope labeling method and mass balance calculation were adopted in a simulated biokarst environment with a series of set pH conditions and three microalgal species. Three key processes of the microalgal biokarst system, including calcite dissolution, CaCO3 reprecipitation, and inorganic carbon assimilation by microalgae, were completely quantitatively described. The combined effects of chemical dissolution and species-specific biodissolution caused a decrease in overall dissolution rate when the pH increased from 7 to 9. CaCO3 reprecipitation and the utilization of dissolved inorganic carbon originating from calcite dissolution decreased when the pH increased from 7 to 9. The three processes exhibited different effects in changing the CO2 atmosphere. The amount of photosynthetic carbon sink was larger at high pH values than at low pH values. However, the CO2 sequestration related to the biokarst process (biokarst carbon sink) increased with decreasing pH. Overall, the total amount of sequestered CO2 produced by the biokarst system (CaCO3-CO2-microalgae) shows a minimum at a specific pH then increases with decreasing pH. Therefore, various processes and carbon sinks in the biokarst system are sensitive to pH changes, and biokarst processes play an important negative feedback role in the release of CO2 by acidification. The results also suggest that the carbon sink associated with carbonate weathering cannot be neglected when considering the global carbon cycle on the scale of thousands of years (<3 ka).

  5. Tracing of γ-radiation-induced electrical conductivity and pH change of hexamethylenetetramine aqueous solutions and its applications.

    Science.gov (United States)

    Sife-Eldeen, Kh A

    2013-04-01

    The interest in studying γ-radiation effects on hexamethylenetetramine (HMTA) is due to its importance in nuclear fuel technology. The current study indicates that γ-radiation induces electrical conductivity (RIC) and pH changes in HMTA aqueous solutions. The effects of HMTA concentration, absorbed radiation dose, absorbed dose rate and storage time on RIC and pH changes were studied. HMTA aqueous solutions could be considered as a promising γ-radiation dosimeter, in both technical and medical fields.

  6. In vivo tumour extracellular pH monitoring using electron paramagnetic resonance: the effect of X-ray irradiation.

    Science.gov (United States)

    Goodwin, Jonathan; Yachi, Katsuya; Nagane, Masaki; Yasui, Hironobu; Miyake, Yusuke; Inanami, Osamu; Bobko, Andrey A; Khramtsov, Valery V; Hirata, Hiroshi

    2014-04-01

    The in vivo quantification of extracellular pH (pHe ) in tumours may provide a useful biomarker for tumour cell metabolism. In this study, we assessed the viability of continuous-wave electron paramagnetic resonance (CW-EPR) spectroscopy with a pH-sensitive nitroxide for the measurement of extracellular tumour pH in a mouse model. CW-EPR spectroscopy (750 MHz) of C3H HeJ mice hind leg squamous cell tumour was performed after intravenous tail vein injection of pH-sensitive nitroxide (R-SG, 2-(4-((2-(4-amino-4-carboxybutanamido)-3-(carboxymethylamino)-3-oxoproylthio)methyl)phenyl)-4-pyrrolidino-2,5,5-triethyl-2,5-dihydro-1Н-imidazol-1-oxyl) during stages of normal tumour growth and in response to a single 10-Gy dose of X-ray irradiation. An inverse relationship was observed between tumour volume and pHe value, whereby, during normal tumour growth, a constant reduction in pHe was observed. This relationship was disrupted by X-ray irradiation and, from 2-3 days post-exposure, a transitory increase in pHe was observed. In this study, we demonstrated the viability of CW-EPR spectroscopy using R-SG nitroxide to obtain high-sensitivity pH measurements in a mouse tumour model with an accuracy of <0.1 pH units. In addition, the measured changes in pHe in response to X-ray irradiation suggest that this may offer a useful method for the assessment of the physiological change in response to existing and novel cancer therapies. Copyright © 2014 John Wiley & Sons, Ltd.

  7. Ocean circulation and biogeochemistry moderate interannual and decadal surface water pH changes in the Sargasso Sea

    Science.gov (United States)

    Nathalie F. Goodkin,; Bo-Shian Wang,; Chen-Feng You,; Konrad Hughen,; Prouty, Nancy G.; Bates, Nicholas; Scott Doney,

    2015-01-01

    The oceans absorb anthropogenic CO2 from the atmosphere, lowering surface ocean pH, a concern for calcifying marine organisms. The impact of ocean acidification is challenging to predict as each species appears to respond differently and because our knowledge of natural changes to ocean pH is limited in both time and space. Here we reconstruct 222 years of biennial seawater pH variability in the Sargasso Sea from a brain coral, Diploria labyrinthiformis. Using hydrographic data from the Bermuda Atlantic Time-series Study and the coral-derived pH record, we are able to differentiate pH changes due to surface temperature versus those from ocean circulation and biogeochemical changes. We find that ocean pH does not simply reflect atmospheric CO2 trends but rather that circulation/biogeochemical changes account for >90% of pH variability in the Sargasso Sea and more variability in the last century than would be predicted from anthropogenic uptake of CO2 alone.

  8. Hydrogen peroxide-induced changes in intracellular pH of guard cells precede stomatal closure

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Epidermal bioassay demonstrated that benzylamine,a membrane-permeable weak base,can mimick hydrogen peroxide (H2O2) to induce stomatal closure,and butyric acid,a membrane-permeable weak acid,can partly abolish the H2O2-induced stomatal closure.Confocal pH mapping with the probe 5-(and-6)-carboxy seminaphthorhodafluor-1-acetoxymethylester (SNARF-1-AM) revealed that H2O2 leads to rapid changes in cytoplasmic and vacuolar pH in guard cells of Vicia faba L,i.e.alkalinization of cytoplasmic areas occur red in parallel with a decrease of the vacuolar pH,and that butyric acid pretreatment can abolish alkalinization of cytoplasmic areas and acidification of vacuolar areas of guard cells challenged with H2O2.These results imply that the alkalinization of cytoplasm via efflux of cytosol protons into the vacuole in guard cells challenged with H2O2 is important at an early stage in the signal cascade leading to stomatal closure.

  9. Interaction of NPK Fertilizers During Their Transformation in Soils:I.Dynamic Changes of Soil pH

    Institute of Scientific and Technical Information of China (English)

    WANG HUOYAN; ZHOU JIANMIN; CHEN XIAOQIN; LI SHOUTIAN; DU CHANGWEN; DONG CAIXIA

    2003-01-01

    Dynamic changes of soil pH as influenced by ammonium sulfate (AS), monocalcium phosphate (MCP),potassium chloride (KCl) and their interaction in soils were evaluated in incubation experiments. Applyingthese fertilizers significantly reduced soil pH values in all cases and followed sequences of AS > MCP >KCl, MCP > KCl > AS and KCl > AS > MCP for the paddy, calcareous and red soils, respectively. TheAS-induced reduction of pH in the three soils followed the sequence of red soil > paddy soil > calcareous soil,while in MCP and KCl systems the reduction of pH followed the sequences of calcareous soil > paddy soil >red soil and red soil > calcareous soil > paddy soil, respectively. The interactions of the NPK fertilizers on pHwere significant. MCP plus KCl or MCP plus AS reduced pH values more than the fertilizers applied solelyin the paddy soil, but AS partly counteracted the effect of MCP on pH in the 1 d sample of the calcareoussoil. The effect of MCP on pH was trivial when MCP was applied in combination with KCl or AS in the redsoil. When applied in combination with AS, KCl did not affect soil pH initially, but suppressed the reductionof pH at the later incubation stage, which was related to inhibition of nitrification by KCl in the soils.

  10. A capillary electrophoresis method with dynamic pH junction stacking for the monitoring of cerebroside sulfotransferase.

    Science.gov (United States)

    Li, Wenjin; Zech, Isabell; Gieselmann, Volkmar; Müller, Christa E

    2015-08-14

    Metachromatic leukodystrophy (MLD) is a rare and severe genetic disease. Inhibition of cerebroside sulfotransferase (CST) has been proposed as a promising new therapeutic strategy for the treatment of MLD. CST catalyzes the transfer of a sulfate group from the coenzyme 3'-phosphoadenosine-5'-phosphosulfate (PAPS) to cerebroside yielding cerebroside sulfate and adenosine-3',5'-diphosphate (PAP). So far only a few weak CST inhibitors have been described. The goal of the present study was to establish a suitable assay for identifying and characterizing novel CST inhibitors. To this end, we developed and optimized a capillary electrophoresis (CE) based assay for monitoring the catalytic activity of CST by measuring the formation of PAP. A sample matrix consisting of 5mM phosphate buffer with about 0.0001% polybrene at pH 7.4 and a background electrolyte (BGE) containing 75 mM phosphate buffer with 0.002% polybrene at pH 5.6 were utilized to achieve a stacking effect for PAP by dynamic pH junction. This led to a limit of detection for the enzymatic product PAP of 66.6 nM. The CE method was sensitive, robust, and suitable for CST inhibitor screening, Ki value determination, and enzyme kinetic studies. Selected reference compounds were tested in order to validate the assay, including the substrates cerebroside and psychosine, and the inhibitor Congo Red. The newly developed CE method will be useful for the identification and development of novel CST inhibitors which are urgently needed for the treatment of MLD.

  11. Suppress or not to suppress gastric acid?Intra-gastric pH monitoring Vs. Litmus paper in critically ill patients

    Directory of Open Access Journals (Sweden)

    Mojtaba Mojtahedzadeh

    2007-06-01

    Full Text Available Stress ulceration and gastrointestinal bleeding complicates many clinical illnesses in patients in the intensive care unit (ICU.  We hypothesized that suppression of gastric acid and monitoring of gastric pH using intra-gastric pH monitoring can be beneficial to critically ill patients. To test this idea we have performed a pilot study to compare the accuracy of litmus paper to determine gastric pH to a nasogastric platin-antimony pH probe in a teaching hospital in Tehran. Twenty critically ill patients in intensive care unit who required stress ulcer prophylaxis, by using a crossover design the patients randomized to initially received ranitidine by continuous infusion or intravenous bolus and subsequently were crossed over to the other arm of the study. Gastric pH was determined using pH sensitive litmus paper at the initiation of each arm of the study and at 1, 2, 4 and 8 hours after the initiation of ranitidine. In addition, gastric pH was continuously determined over the same time utilizing a platin-antimony pH probe made in Iran. Pilot Results of gastric pH measurement determined with litmus paper and intra-gastric pH probes demonstrated by regression analysis comparing these two methods showed a good correlation between the two methods (r=0.7. The pH probe technique for intra-gastric pH measurement appears to be technically simple and clinically applicable for use on patients at risk for stress ulcer bleeding.  It may be more accurate than litmus paper in patient receiving H2 antagonists. Further investigations are needed to validate this idea.

  12. Fluorescence measurements of serotonin-induced V-ATPase-dependent pH changes at the luminal surface in salivary glands of the blowfly Calliphora vicina.

    Science.gov (United States)

    Rein, Julia; Zimmermann, Bernhard; Hille, Carsten; Lang, Ingo; Walz, Bernd; Baumann, Otto

    2006-05-01

    Secretion in blowfly salivary glands is induced by the neurohormone serotonin and powered by a vacuolar-type H(+)-ATPase (V-ATPase) located in the apical membrane of the secretory cells. We have established a microfluorometric method for analysing pH changes at the luminal surface of the secretory epithelial cells by using the fluorescent dye 5-N-hexadecanoyl-aminofluorescein (HAF). After injection of HAF into the lumen of the tubular salivary gland, the fatty acyl chain of the dye molecule partitions into the outer leaflet of the plasma membrane and its pH-sensitive fluorescent moiety is exposed at the cell surface. Confocal imaging has confirmed that HAF distributes over the entire apical membrane of the secretory cells and remains restricted to this membrane domain. Ratiometric analysis of HAF fluorescence demonstrates that serotonin leads to a reversible dose-dependent acidification at the luminal surface. Inhibition by concanamycin A confirms that the serotonin-induced acidification at the luminal surface is due to H(+) transport across the apical membrane via V-ATPase. Measurements with pH-sensitive microelectrodes corroborate a serotonin-induced luminal acidification and demonstrate that luminal pH decreases by about 0.4 pH units at saturating serotonin concentrations. We conclude that ratiometric measurements of HAF fluorescence provide an elegant method for monitoring V-ATPase-dependent H(+) transport in the blowfly salivary gland in vivo and for analysing the spatiotemporal pattern of pH changes at the luminal surface.

  13. [Short-term changes of pH value and Al activity in acid soils after urea fertilization].

    Science.gov (United States)

    Zeng, Qingru; Liao, Bohan; Jiang, Zhaohui; Zhou, Xihong; Tang, Can; Zhong, Ning

    2005-02-01

    Acidic soils are widely distributed in South China, and their acidity is the major environmental stress factor limiting the growth of most crops. It is well known that soil Al solubilized at low pH is a main toxic factor for plant growth. Our study with three acidic soils showed that soil pH increased quickly, while soil exchangeable Al decreased sharply with the increasing concentrations of applied urea. The time-course experiment revealed that the increase of soil pH was short-lived, with a subsequently slow drop after reached its maximum. Urea fertilization caused a drastic change of soil pH during 2-4 weeks of the experimental period. There was a negative relationship between soil pH and soil exchangeable Al. Biological toxicity test demonstrated that applying urea to acidic soils could obviously decrease the aluminum toxicity of maize in a short-term period.

  14. Continuous intragastric pH monitoring in the evaluation of ebrotidine, cimetidine and placebo on gastric acidity in healthy volunteers.

    Science.gov (United States)

    Muñoz-Navas, M; Honorato, J; Reina-Ariño, M; Márquez, M; Herrero, E; Villamayor, F; Torres, J; Roset, P N; Fíllat, O; Camps, F; Ortiz, J A

    1997-04-01

    This study was conducted to determine the efficacy and tolerance of ebrotidine (N-[(E)-[[2-[[[2-[(diaminomethylene)amino]-4-thiazolyl) methyl]thio]ethyl]amino]methylene]-4-bromo-benzenesulfonamide, CAS 100981-43.9, FI-3542), a new H2-receptor antagonist, on reducing gastric acidity after a single 800 mg dose, compared with cimetidine 800 mg once daily and placebo by means of a continuous intragastric pH monitoring. A total of 30 healthy volunteers were allocated to receive in a double blind, parallel design the study medication. Clinical observations, physical examinations and visual analogue scales (VAS) were performed during the study to assess the tolerability of the three treatments. Ebrotidine and cimetidine caused a greater and longer-lasting gastric acid inhibition than placebo. With ebrotidine, significantly (p < 0.05) higher median pH values (and interquartile range, IQR) were reached in the post-administration (2.61, IQR 2.02-3.93), postprandial (3.38, IQR 2.82-3.91) and nocturnal (2.83, IQR 1.69-3.77) periods than with placebo: 1.82 (IQR, 1.66-2.09), 2.81 (IQR, 2.02-3.28), and 1.89 (IQR, 1.44-2.13), respectively. Cimetidine showed significant differences compared to placebo in the post-administration (2.36, IQR 1.89-3.46) and nocturnal (2.46, IQR 1.88-4.33) periods. No statistical differences were observed between the active treatments. Ebrotidine caused a significantly higher percentage of time above pH 2.0 in the post-administration and nocturnal periods compared to placebo (p < 0.05), and above pH 3.0 in the post-administration, postprandial and nocturnal periods. No serious adverse effects, or disturbances in the VAS or in the vital signs were reported, and all medications were well tolerated. It is concluded that a single dose of ebrotidine 800 mg is as effective as cimetidine 800 mg in reducing total and nocturnal intragastric acidity. The study also confirms the excellent safety profile of the new drug.

  15. Investigating the contributing factors to postmortem pH changes in springbok, eland, red hartebeest and kudu edible offal

    Directory of Open Access Journals (Sweden)

    Kudakwashe Magwedere

    2013-03-01

    Full Text Available The objective of the study was to assess pH measurements between offal organs of different species and the association between pH taken 4 h post-slaughter and different predictor variables in the liver and lungs. A linear regression analysis was conducted on selected variables to identify the main predictors and their interactions affecting the pH of meat 4 h post-slaughter. In an increasing order of magnitude during winter, the pH achieved at 16 h – 36 h post-slaughter in springbok heart, liver, spleen, kidney and lungs was significantly (p < 0.05 higher than pH 6.0. The pH attained in springbok carcasses was (p < 0.05 below 6.0, whilst no significant differences were observed from the regulatory reference (pH 6.0 in the heart. There was a positive association between the pH of game meat 4 h post-slaughter and liver congestion. The pH of game meat 4 h post-slaughter increased by 0.11 units (p < 0.05 per millilitre increase in liver congestion and decreased by 0.04 units (p< 0.05 per minute increase in the shooting-to-bleeding interval, irrespective of the species. The lack of a statistically significant association between some selected variables and pH changes in this study suggested that either the factors may have a small effect which is only detectable with large data-sets and/or the effect may be modified by other unidentified factors. As some of the offal organs had final pH readings above 6.0, alternative measures are required to inactivate certain endogenous pathogens in edible wild game offal sourced from endemic areas.

  16. Characterisation of spatial and temporal changes in pH gradients in microfluidic channels using optically trapped fluorescent sensors.

    Science.gov (United States)

    Klauke, Norbert; Monaghan, Paul; Sinclair, Gavin; Padgett, Miles; Cooper, Jon

    2006-06-01

    This paper demonstrates the use of micron sized beads, modified with fluorescent dyes, as non-invasive sensors to probe the local changes in pH, within a microfluidic channel. To achieve this, amine modified polystyrene spheres (either 3 microm or 6 microm in diameter) were functionalised with the pH sensitive fluorochrome SNARF-1 to produce point sensors. The modified beads were trapped at defined positions close to a pair of integrated planar gold microelectrodes within the channel, using optical tweezers. Both transient and steady-state electrochemical potentials were applied to the microelectrode pair in order to generate changes in the local pH, associated with electrolysis. The functionalised beads indicated the pH changes in the channel, measured as a change in the fluorescence signal, generated by the immobilised pH sensitive dye. Responses were measured with temporal resolutions of between 1 and 200 ms, whilst the spatial resolution of the pH gradients was limited by the size of the beads to 3 microm.

  17. Guidance on Monitoring of Gross Changes in Forest Area

    OpenAIRE

    Achard, Frederic; DeFries, Ruth; Herold, Martin; Mollicone, Danilo; Pandey, Devendra; Souza, Carlos

    2008-01-01

    This chapter presents the state of the art for data and approaches to be used for monitoring forest area changes at the national scale in tropical countries using remote sensing imagery. It includes approaches and data for monitoring both deforestation and forest degradation and for establishing historical reference scenarios. The chapter presents the minimum requirements to develop first order national deforestation databases, using typical and internationally accepted methods. There are ...

  18. The pH changes of artificial saliva after interaction with oral of artificial saliva after interaction with oral micropathogen

    Directory of Open Access Journals (Sweden)

    Basri A. Gani

    2012-12-01

    Full Text Available Backgorund: Saliva contains several protein elements, exocrine proteins and antibodies, such as lactoferrin, sIgA, peroxidase, albumin, polypeptides, and oligopeptides that contribute to the defense of oral mucosa and dental pellicle to prevent infection caused by oral micropathogen, such as Candida albicans, Streptococcus mutans and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans. Those micropathogens have a role to change salivary pH as an indicator of oral disease activities. Purpose: This study was aimed to analyze the changes of artificial saliva pH after interaction with S. mutans, C. albicans, and A. Actinomycetemcpmitans. Methods: The materials used in this study consist of S. mutans (ATCC 31987, C. albicans (ATCC 10231, A. actinomycetemcomitans (ATTC 702 358, and artificial saliva. To examine the pH changes of artificial saliva, those three microbiotas were cultured and incubated for 24 hours. Results: The results showed that the interactions of S. mutans, C. albicans, and A. actinomycetemcomitans in the artificial saliva can change the salivary on neutral. There were no significant difference with the control treatment salivary pH 4, 5, 6, 8, and 9 (p>0.05. Similarly, there was also no significant difference when those three microorganism interacted each other in the artificial saliva (p<0.05. Conclusion: It can be concluded that the biological activity of S. mutans, C. albicans, and A. actinomycetemcomitans in artificial saliva can change the salivary pH into neutral. It indicates that those microbiotas mutually supported and cooperated in influencing the biological cycle of the oral cavity with salivary pH as an indicator.Latar belakang: Saliva merupakan cairan eksokrin yang mengandung unsur protein dan antibodi seperti sIgA laktoferin peroksidase, albumin, polipeptida dan oligopeptida yang berperan pada pertahanan mukosa rongga mulut dan gigi guna mencegah infeksi oral mikropatogen seperti C. albicans, S. mutans, dan

  19. Metal release from contaminated estuarine sediment under pH changes in the marine environment.

    Science.gov (United States)

    Martín-Torre, M Camino; Payán, M Cruz; Verbinnen, Bram; Coz, Alberto; Ruiz, Gema; Vandecasteele, Carlo; Viguri, Javier R

    2015-04-01

    The contaminant release from estuarine sediment due to pH changes was investigated using a modified CEN/TS 14429 pH-dependence leaching test. The test is performed in the range of pH values of 0-14 using deionised water and seawater as leaching solutions. The experimental conditions mimic different circumstances of the marine environment due to the global acidification, carbon dioxide (CO2) leakages from carbon capture and sequestration technologies, and accidental chemical spills in seawater. Leaching test results using seawater as leaching solution show a better neutralisation capacity giving slightly lower metal leaching concentrations than when using deionised water. The contaminated sediment shows a low base-neutralisation capacity (BNCpH 12 = -0.44 eq/kg for deionised water and BNCpH 12 = -1.38 eq/kg for seawater) but a high acid-neutralisation capacity when using deionised water (ANCpH 4 = 3.58 eq/kg) and seawater (ANCpH 4 = 3.97 eq/kg). Experimental results are modelled with the Visual MINTEQ geochemical software to predict metal release from sediment using both leaching liquids. Surface adsorption to iron- and aluminium-(hydr)oxides was applied for all studied elements. The consideration of the metal-organic matter binding through the NICA-Donnan model and Stockholm Humic Model for lead and copper, respectively, improves the former metal release prediction. Modelled curves can be useful for the environmental impact assessment of seawater acidification due to its match with the experimental values.

  20. The Microstructure and Bulk Rheology of Human Cervicovaginal Mucus are Remarkably Resistant to Changes in pH

    OpenAIRE

    Wang, Ying-Ying; Lai, Samuel K.; Ensign, Laura; Zhong, Weixi; Cone, Richard; Hanes, Justin

    2013-01-01

    The protective barrier, lubricant and clearance functions of mucus are intimately coupled to its microstructure and bulk rheology. Mucus gels consist of a network of mucin biopolymers along with lipids, salts and other proteins, and exhibit similar biochemical and physical properties across diverse mucosal surfaces. Nevertheless, mucus is exposed to a broad range of pH throughout the human body. Protein functions are typically sensitive to small changes in pH, and prior investigations using r...

  1. Proton pump inhibitors for reflux therapy in infants: effectiveness determined by impedance pH monitoring.

    Science.gov (United States)

    Castellani, Christoph; Huber-Zeyringer, Andrea; Bachmaier, Gerhard; Saxena, Amulya K; Höllwarth, Michael E

    2014-04-01

    To evaluate the influence of proton pump inhibitors (PPI) in predominantly milk-fed infants with symptoms of GERD by 24-h pH-multichannel intraluminal impedance (24-h pH-MII). Ten infants (8 males and 2 females) with a mean gestational age of 39 weeks (28-40) were included. 24-h pH-MII was performed before prescription and during intake of PPI. Total acid exposure time, bolus exposure time (acidic/non-acidic/total) and the number of refluxes (acidic/non-acidic/total) were determined. Clinical symptoms were recorded and used to calculate the Reflux Symptom Index (RSI) and the Symptom Severity Index (SSI). There was a significant decrease in the number of acidic refluxes, total acid exposure and acidic bolus exposure time. However, this went along with a significant increase in non-acidic bolus exposure time. The total number of refluxes and the total bolus exposure time remained unchanged. Under PPI, a decrease of SSI and RSI for pain-related symptoms could be observed. For respiratory symptoms and vomiting however no significant changes could be demonstrated. Under PPI, an improvement of pain-related symptoms could be shown. The decrease of acid exposure went along with an increase of non-acidic refluxes resulting in almost constant total reflux numbers. This finding is interpreted as main reason for some persisting symptoms despite adequate PPI dosage. Concluding from our data PPI therapy should only be indicated in case of pain, but has no effect in case of vomiting or recurrent respiratory symptoms.

  2. [Aluminum dissolution and changes of pH in soil solution during sorption of copper by aggregates of paddy soil].

    Science.gov (United States)

    Xu, Hai-Bo; Zhao, Dao-Yuan; Qin, Chao; Li, Yu-Jiao; Dong, Chang-Xun

    2014-01-01

    Size fractions of soil aggregates in Lake Tai region were collected by the low-energy ultrasonic dispersion and the freeze-desiccation methods. The dissolution of aluminum and changes of pH in soil solution during sorption of Cu2+ and changes of the dissolution of aluminum at different pH in the solution of Cu2+ by aggregates were studied by the equilibrium sorption method. The results showed that in the process of Cu2+ sorption by aggregates, the aluminum was dissoluted and the pH decreased. The elution amount of aluminum and the decrease of pH changed with the sorption of Cu2+, both increasing with the increase of Cu2+ sorption. Under the same conditions, the dissolution of aluminum and the decrease of pH were in the order of coarse silt fraction > silt fraction > sand fraction > clay fraction, which was negatively correlated with the amount of iron oxide, aluminum and organic matter. It suggested that iron oxide, aluminum and organic matters had inhibitory and buffering effect on the aluminum dissolution and the decrease of pH during the sorption of Cu2+.

  3. A Study on Changes of Supervision Model in Universities and Fostering Creative PhD Students in China

    DEFF Research Database (Denmark)

    Luo, Lingling; Zhou, Chunfang; Zhang, Song

    2015-01-01

    This paper aims to explore the changes of supervision model in higher education in relation to fostering creative Ph.D. students in China. The changes are being made from the traditional Apprentice Master Model (AMM) to the modern Collaborative Cohort Model (CCM). According to the results of the ...

  4. Self-Perception of Swallowing-Related Problems in Laryngopharyngeal Reflux Patients Diagnosed with 24-Hour Oropharyngeal pH Monitoring

    Directory of Open Access Journals (Sweden)

    Tamer A. Mesallam

    2016-01-01

    Full Text Available Background and Objectives. Swallowing difficulty is considered one of the nonspecific symptoms that many patients with laryngopharyngeal reflux complain of. However, the relationship between laryngopharyngeal reflux and swallowing problems is not clear. The purpose of this work is to explore correlation between swallowing-related problems and laryngopharyngeal reflux (LPR in a group of patients diagnosed with oropharyngeal pH monitoring and to study the effect of laryngopharyngeal reflux on the patients’ self-perception of swallowing problems. Methods. 44 patients complaining of reflux-related problems were included in the study. Patients underwent 24-hour oropharyngeal pH monitoring and were divided into positive and negative LPR groups based on the pH monitoring results. All patient filled out the Dysphagia Handicap Index (DHI and Reflux Symptom Index (RSI questionnaires. Comparison was made between the positive and negative LPR groups regarding the results of the DHI and RSI ratings. Also, correlation between DHI scores, RSI scores, and pH monitoring results was studied. Results. Significant difference was reported between positive and negative LPR groups regarding DHI scores, RSI scores, and overall rating of swallowing difficulty. There was significant correlation demonstrated between DHI scores, RSI scores, and 24-hour oropharyngeal pH results. Conclusion. Laryngopharyngeal reflux appears to have a significant impact on patients’ self-perception of swallowing problems as measured by DHI.

  5. Environmental monitoring in the making: from surveying nature's resources to monitoring nature's change

    OpenAIRE

    Aronova, Elena

    2015-01-01

    This article examines the nexus of ecological science and environmental politics by considering the tensions between the global circulation of the notion of “environmental monitoring” and the local production of data on environmental change. The history of the planning of the Global Network of Environmental Monitoring (GNEM) program provides a glimpse of what it takes to launch a program of environmental monitoring globally on the level of intergovernmental organizations, such as the United N...

  6. Factors affecting pH change in alkaline waste water treatment - I

    NARCIS (Netherlands)

    Lijklema, L.

    1969-01-01

    The pH of wastewater in various stages of its purification depends mainly upon the equilibria of carbonic acid. Thus relations between pH and the concentrations of carbon dioxide, bicarbonate and carbonate can be formulated. Corrections for the non-ideal character of the sewage are necessary. With s

  7. Effect of carbon dioxide and ammonium removal on pH changes in polishing ponds

    NARCIS (Netherlands)

    Cavalcanti, P.F.F.; Haandel, van A.; Lettinga, G.

    2002-01-01

    If nutrient removal is to be obtained in ponds treating sewage, the pH must be raised so that ammonia can desorb and phosphates can precipitate. In this paper it is shown that the pH increase in ponds can be predicted quantitatively from simple stoichiometry, taking into consideration physical and b

  8. Polyhedral charge-packing model for blood pH changes in disease ...

    African Journals Online (AJOL)

    Administrator

    2007-05-02

    May 2, 2007 ... 7.65 as the extreme upper limit of tolerable alkalosis. Experimental results from ... of the tetrahedron-based tolerable, stable, low limit pH in acidosis. Some medical .... things, respiratory and metabolic, that keep the pH in the.

  9. Metal Sequestration Is Influenced By Biochar Properties and Changes in pH

    Science.gov (United States)

    Clemente, J.; Beauchemin, S.; MacKinnon, T.; Martin, J.; Joern, B.; Johnston, C. T.

    2014-12-01

    Addition of biochars to impounded metal mine waste may improve the physical and chemical properties, and the biological activity and diversity of these contaminated sites. However, understanding how biochar addition influences metal(loid) mobility is necessary. Here, the sequestration of 5 metal(loid)s in suspensions of biochars adjusted to pH 4.5 or 6.0 were characterized. Solutions of the oxyanion As and the cations Ni, Cu, Zn, Cd were added at a single rate of 3 mmol kg-1 biochar. Six biochars were obtained by large-scale pyrolysis of softwood, hardwood, grass, and poultry litter under different conditions. Biochars were characterized using N2-BET (surface area), proximate analysis, elemental analysis, X-ray diffraction and Fourier transform infrared spectroscopy. In this study, metal(loid) sequestration depended on the suspension pH, metal(loid), and biochar characteristics. In most cases, a significantly (α=0.05) greater proportion of cation was sequestered in biochar suspensions adjusted to pH 6.0 compared to pH 4.5. In contrast, pH had no significant effect on the sequestration of As. The magnitude of the increase in sequestration at pH 6.0 compared to pH 4.5 can be attributed to specific biochar characteristics. Enhancement of Ni, Zn, and Cd sequestration at pH 6.0 compared to pH 4.5 was correlated (R2>0.50) to inorganic C content and neutralization potential of biochars. Furthermore, increased Cu sequestration at pH 6.0 compared to pH 4.5 was correlated (R2>0.50) to % Fixed matter and organic C content of biochars. This data suggests that at pH 6.0, sequestration of Ni, Zn, and Cd as carbonates and interactions between organic C and Cu were more favourable compared to pH 4.5. For Ni, Cu, and Cd, differences in sequestration at the two pH were also related (R2>0.50) to the relative distribution of functional groups. This study emphasizes the need for a more holistic understanding of how biochar properties influence metal sequestration.

  10. Conformational changes in the bilirubin-human serum albumin complex at extreme alkaline pH

    DEFF Research Database (Denmark)

    Honoré, B; Frandsen, P C

    1986-01-01

    Light-absorption, c.d. and fluorescence of the bilirubin-albumin complex were investigated at extreme alkaline pH. Above pH 11.1 albumin binds the bilirubin molecule, twisted oppositely to the configuration at more neutral pH. On the basis of light-absorption it is shown that two alkaline...... transitions occur. The first alkaline transition takes place at pH between 11.3 and 11.8, co-operatively dissociating at least six protons. The second alkaline transition takes place at pH between 11.8 and 12.0. It probably implies a reversible unfolding of the albumin molecule, increasing the distance...

  11. Intertidal epilithic bacteria diversity changes along a naturally occurring carbon dioxide and pH gradient.

    Science.gov (United States)

    Taylor, Joe D; Ellis, Rebecca; Milazzo, Marco; Hall-Spencer, Jason M; Cunliffe, Michael

    2014-09-01

    Intertidal epilithic bacteria communities are important components of coastal ecosystems, yet few studies have assessed their diversity and how it may be affected by changing environmental parameters. Submarine CO2 seeps produce localised areas of CO2-enriched seawater with reduced pH levels. We utilised the seawater pH/CO2 gradient at Levante Bay (Italy) to test the hypothesis that epilithic bacteria communities are modified by exposure to seawater with the varying chemical parameters. Biofilms were sampled from three sites exposed to seawater with different pH/CO2 levels and diversity determined using high-throughput sequencing of 16S rRNA genes. Seawater pCO2 concentrations were increased from ambient at site 1 to 621 μatm at site 2 and 1654 μatm site 3, similar to the predicated future oceans beyond 2050 and 2150, respectively. Alpha diversity of total bacteria communities and Cyanobacteria communities was significantly different between sites (anova P ocean acidification on coastal marine ecosystems.

  12. The microstructure and bulk rheology of human cervicovaginal mucus are remarkably resistant to changes in pH.

    Science.gov (United States)

    Wang, Ying-Ying; Lai, Samuel K; Ensign, Laura M; Zhong, Weixi; Cone, Richard; Hanes, Justin

    2013-12-09

    The protective barrier, lubricant, and clearance functions of mucus are intimately coupled to its microstructure and bulk rheology. Mucus gels consist of a network of mucin biopolymers along with lipids, salts, and other proteins and exhibit similar biochemical and physical properties across diverse mucosal surfaces. Nevertheless, mucus is exposed to a broad range of pH values throughout the human body. Protein functions are typically sensitive to small changes in pH, and prior investigations using reconstituted, purified mucin gels suggested mucus undergoes a transition from a low-viscosity liquid at neutral pH to a highly viscoelastic solid at low pH. We sought to determine whether those observations hold for fresh, minimally perturbed human mucus ex vivo by using different-sized muco-inert nanoparticles to probe microstructure and cone-and-plate rheometry to measure bulk rheology. We demonstrate that both the microstructure and bulk rheology of fresh, undiluted, and minimally perturbed cervicovaginal mucus exhibit relatively minor changes from pH 1-2 to 8-9, in marked contrast with the pH sensitivity of purified mucin gels. Our work also suggests additional components in mucus secretions, typically eliminated during mucin purification and reconstitution, may play an important role in maintaining the protective properties of mucus.

  13. Loblolly pine (Pinus taeda) female gametophyte and embryo pH changes during seed development.

    Science.gov (United States)

    Pullman, Gerald S; Johnson, Shannon

    2009-06-01

    Stage-specific measurements of female gametophyte (FG) and embryo pH (hydrogen ion concentration) were made through the sequence of loblolly pine (Pinus taeda L.) seed development. The FG tissue from two open-pollinated trees showed similar pH profiles starting at 5.5 shortly after fertilization, increasing to about 6.1 at stage 7, levelling off at 6.3-6.5 towards the end of development and dropping to 6.0 just before cone opening. Measurements of the chalazal end were 0.05-0.2 pH units less than the micropylar end through early-to-mid-development. In contrast, embryo pH maintained a nearly constant value near 7.0 through development. Profiles of pH through seed development were similar whether portrayed by date or stage of embryo present in the seed. The pH profiles assisted in the development of improved embryogenic tissue initiation techniques. When post-autoclaving maturation medium pH was raised from about 5.3 in control medium to 5.7 or 5.5-5.7 with 2(n-morpholino)ethanesulphonic acid, cotyledonary embryo yields increased.

  14. Monitoring and verifying changes of organic carbon in soil

    Science.gov (United States)

    Post, W.M.; Izaurralde, R. C.; Mann, L. K.; Bliss, Norman B.

    2001-01-01

    Changes in soil and vegetation management can impact strongly on the rates of carbon (C) accumulation and loss in soil, even over short periods of time. Detecting the effects of such changes in accumulation and loss rates on the amount of C stored in soil presents many challenges. Consideration of the temporal and spatial heterogeneity of soil properties, general environmental conditions, and management history is essential when designing methods for monitoring and projecting changes in soil C stocks. Several approaches and tools will be required to develop reliable estimates of changes in soil C at scales ranging from the individual experimental plot to whole regional and national inventories. In this paper we present an overview of soil properties and processes that must be considered. We classify the methods for determining soil C changes as direct or indirect. Direct methods include field and laboratory measurements of total C, various physical and chemical fractions, and C isotopes. A promising direct method is eddy covariance measurement of CO2 fluxes. Indirect methods include simple and stratified accounting, use of environmental and topographic relationships, and modeling approaches. We present a conceptual plan for monitoring soil C changes at regional scales that can be readily implemented. Finally, we anticipate significant improvements in soil C monitoring with the advent of instruments capable of direct and precise measurements in the field as well as methods for interpreting and extrapolating spatial and temporal information.

  15. Changes in rumen microbial fermentation are due to a combined effect of type of diet and pH.

    Science.gov (United States)

    Calsamiglia, S; Cardozo, P W; Ferret, A; Bach, A

    2008-03-01

    Low ruminal pH may occur when feeding high-concentrate diets. However, because the reduction in pH occurs at the same time as the amount of concentrate fed increases, the changes observed in rumen fermentation may be attributed to pH or the type of substrate being fermented. Our objective was to determine the contribution of pH and type of substrate being fermented to the changes observed in rumen fermentation after supplying a high-concentrate diet. Eight dual-flow, continuous culture fermenters (1,400 mL) were used in 4 periods to study the effect of pH and type of diet being fermented on rumen microbial fermentation. Temperature (39 degrees C), solid (5%/h), and liquid (10%/h) dilution rates, and feeding schedule were maintained constant. Treatments were the type of diet (FOR = 60% ryegrass and alfalfa hays and 40% concentrate; CON = 10% straw and 90% concentrate) and pH (4.9, 5.2, 5.5, 5.8, 6.1, 6.4, 6.7, and 7.0). Diets were formulated to have similar CP and ruminally undegradable protein levels. Data were analyzed as a mixed-effects model considering the linear, quadratic, and cubic effects of pH, the effects of diet, and their interactions. Semipartial correlations of each independent variable were calculated to estimate the contribution of each factor to the overall relationship. True digestion of OM and NDF were affected by pH, but not by type of diet. Total VFA were reduced by pH and were greater in CON than in FOR. Acetate and butyrate concentrations were reduced by pH but were not affected by diet. Propionate concentration increased as the pH decreased and was greater in CON than in FOR. Ammonia-N concentration decreased with decreasing pH and was lower in CON than in FOR. Microbial N flow was affected by pH, diet, and their interaction. Dietary N flow increased as pH decreased and was greater in CON than in FOR. The degradation of CP followed the opposite pattern, increasing as pH increased, and was less in CON than in FOR. The efficiency of microbial

  16. Evaluation of cytotoxicity and pH changes generated by various dental pulp capping materials - an in vitro study.

    Science.gov (United States)

    Luczaj-Cepowicz, Elzbieta; Marczuk-Kolada, Grazyna; Pawinska, Malgorzata; Obidzinska, Marta; Holownia, Adam

    2017-01-01

    Various materials are used in direct dental pulp capping method. Their biocompatibility and alkalizing abilities are of primary importance affecting therapeutic effects. The aim of this study was to evaluate and compare the cytotoxicity of various pulp-capping materials on human gingival fibroblasts and investigate the pH changes induced by these materials. Human gingival fibroblasts were cultured with nine direct pulp materials using culture plate inserts. The cytotoxic effects were recorded by using an MTT-based colorimetric assay after 3 and 24 h. In the second part of the experiment, the materials were inserted in dialysis tubes and transferred into plastic vials containing deionized water. The changes of the medium pH were measured after 3 and 24 h. We showed differences in cell viability of gingival fibroblasts after varied time of exposition for the tested materials. Cell viability after 24 h increased for Dycal, Biopulp, and Calcipro, and decreased for Calcipulpe, Angelus, Angelus White, and ProRoot Regular. Cell viability for ProRoot and Life did not change. Non-setting calcium hydroxide preparations followed by the MTA group and setting calcium hydroxide materials produced the highest pH. All the tested materials significantly increased pH (p materials varied in their cytotoxicity relative to human gingival fibroblasts and their alkalizing capacities. Since most likely pH does not affect the viability of cultured cells, further investigations are required to determine physicochemical properties of these materials and the biological activity of the dental pulp.

  17. Changes in exhaled breath condensate pH in healthy and asthmatic pregnant women.

    Science.gov (United States)

    Eszes, Noémi; Bikov, András; Lázár, Zsófia; Bohács, Anikó; Müller, Veronika; Stenczer, Balázs; Rigó, János; Losonczy, György; Horváth, Ildikó; Tamási, Lilla

    2013-05-01

    Asthma is a common chronic disease complicating pregnancy with a risk for perinatal complications. Control of airway inflammation in the asthmatic pregnancy improves pregnancy outcomes. Our aim was to evaluate pH of exhaled breath condensate (EBC), a non-invasive method for the assessment of asthmatic airway inflammation, in healthy and asthmatic pregnancies. Cross-sectional study. Hungarian university clinics. Seventeen healthy pregnant women, 21 asthmatic pregnant women, 23 healthy non-pregnant women and 22 asthmatic non-pregnant women. EBC samples were collected using a portable condenser, EBC pH was measured after argon deaeration. EBC pH. EBC pH (mean ± SD) of healthy non-pregnant and asthmatic non-pregnant women was similar (7.75 ± 0.27 vs. 7.54 ± 0.57; p = 0.118), probably indicating an optimal control of airway inflammation in asthmatic women. On the other hand, EBC pH was higher in healthy pregnant women compared with healthy non-pregnant women (8.02 ± 0.43 vs. 7.75 ± 0.27; p = 0.017). Higher EBC pH accompanying healthy pregnancy was absent in asthmatic pregnant patients whose EBC pH was lower (7.65 ± 0.38) than that of healthy pregnant women (p = 0.006), and it was similar to that in asthmatic and healthy non-pregnant women (p = 0.470 and p = 0.300, respectively). The EBC pH in asthmatic pregnant women correlated positively with birthweight (r = 0.49, p = 0.047) and negatively with forced vital capacity (r = 0.45, p = 0.039). EBC pH was not related to blood pH. EBC pH is higher in healthy pregnant women but not in asthmatic pregnant women compared with data from healthy non-pregnant women, indicating that oxidative inflammatory processes induced by asthma may compromise the regulatory mechanisms causing alkaline pH in the airways during pregnancy. © 2013 The Authors Acta Obstetricia et Gynecologica Scandinavica © 2013 Nordic Federation of Societies of Obstetrics and Gynecology.

  18. Gastroesophageal reflux and respiratory tract infection in tube-fed elderly patients. A comparison between scintigraphy and 24-h pH monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Shigehiko; Koichi, Katsuyuki; Tofuku, Yohei [Ishikawa-Ken Saiseikai Kanazawa Hospital (Japan)

    1994-11-01

    Aspiration pneumonia in patients who received enteral feeding via a nasogastric tube may result from retrograde colonization from the stomach, and this may be more likely when the gastroesophageal reflux is severe and the gastric pH is relative high. We investigated 11 elderly patients fed via nasogastric tube with suspected recurrent aspiration pneumonia by means of esophageal scintigraphy, 24-h pH monitoring, gastric pH and concentrations of gram-negative bacilli in gastric aspirates. The grade of respiratory tract infection (RTI) was evaluated by the frequency of episodes of fever with respiratory symptoms. The correlation between the grade of RTI and reflux index by scintigraphy was statistically significant (p<0.05), but the correlation between the grade of RTI and reflux rate by 24-h pH monitoring was not statistically significant. Although the correlation between gastric pH and log (base 10) concentration of gram-negative bacilli/ml of gastric aspirates was statistically significant (p<0.001), the correlation between the grade of RTI and gastric pH was not statistically significant. Scintigraphy was superior for evaluation of gastroesophageal reflux resulting in aspiration pneumonia in the tube-fed elderly patients. (author).

  19. Response of the cytoplasmic and membrane proteome of Corynebacterium glutamicum ATCC 13032 to pH changes

    Directory of Open Access Journals (Sweden)

    Poetsch Ansgar

    2008-12-01

    Full Text Available Abstract Background C. glutamicum has traditionally been grown in neutral-pH media for amino acid production, but in a previous article we reported that this microorganism is a moderate alkaliphile since it grows optimally at pH 7.0–9.0, as shown in fermentor studies under tightly controlled pH conditions. We determined the best pH values to study differential expression of several genes after acidic or basic pH conditions (pH 6.0 for acidic expression and pH 9.0 for alkaline expression. Thus, it was interesting to perform a detailed analysis of the pH-adaptation response of the proteome of C. glutamicum ATCC 13032 to clarify the circuits involved in stress responses in this bacterium. In this paper we used the above indicated pH conditions, based on transcriptional studies, to confirm that pH adaptation results in significant changes in cytoplasmatic and membrane proteins. Results The cytoplasmatic and membrane proteome of Corynebacterium glutamicum ATCC 13032 at different pH conditions (6.0, 7.0 and 9.0 was analyzed by classical 2D-electrophoresis, and by anion exchange chromatography followed by SDS-PAGE (AIEC/SDS-PAGE. A few cytoplasmatic proteins showed differential expression at the three pH values with the classical 2D-technique including a hypothetical protein cg2797, L-2.3-butanediol dehydrogenase (ButA, and catalase (KatA. The AIEC/SDS-PAGE technique revealed several membrane proteins that respond to pH changes, including the succinate dehydrogenase complex (SdhABCD, F0F1-ATP synthase complex subunits b, α and δ (AtpF, AtpH and AtpA, the nitrate reductase II α subunit (NarG, and a hypothetical secreted/membrane protein cg0752. Induction of the F0F1-ATP synthase complex β subunit (AtpD at pH 9.0 was evidenced by Western analysis. By contrast, L-2.3-butanediol dehydrogenase (ButA, an ATPase with chaperone activity, the ATP-binding subunit (ClpC of an ATP-dependent protease complex, a 7 TMHs hypothetical protein cg0896, a conserved

  20. Multiscale dynamics of the cell envelope of Shewanella putrefaciens as a response to pH change.

    Science.gov (United States)

    Gaboriaud, Fabien; Dague, Etienne; Bailet, Sidney; Jorand, Frédéric; Duval, Jérôme; Thomas, Fabien

    2006-10-01

    The bacterial surface properties of gram-negative Shewanella putrefaciens were characterized by microbial adhesion to hydrocarbons (MATH), adhesion to polystyrene dishes, and electrophoresis at different values of pH and ionic strength. The bacterial adhesion to these two apolar substrates shows significant variations according to pH and ionic strength. Such behavior could be partly explained by electrostatic repulsions between bacteria and the solid or liquid interface. However, a similar trend was also observed at rather high ionic strength where electrostatic interactions are supposed to be screened. The nanomechanical properties at pH 4 and 10 and at high ionic strength were investigated by using atomic force microscopy (AFM). The indentation curves revealed the presence of a polymeric external layer that swells and softens up with increasing pH. This suggests a concomitant increase of the water permeability and so did of the hydrophilicity of the bacterial surface. Such evolution of the bacterial envelope in response to changes in pH brings new insight to the pH dependence in the bacterial adhesion tests. It especially demonstrates the necessity to consider the hydrophobic/hydrophilic surface properties of bacteria as not univocal for the various experimental conditions investigated.

  1. Effect of carbon dioxide and ammonium removal on pH changes in polishing ponds.

    Science.gov (United States)

    Cavalcanti, P F F; van Haandel, A; Lettinga, G

    2002-01-01

    If nutrient removal is to be obtained in ponds treating sewage, the pH must be raised so that ammonia can desorb and phosphates can precipitate. In this paper it is shown that the pH increase in ponds can be predicted quantitatively from simple stoichiometry, taking into consideration physical and biological carbon dioxide removal, ammonia stripping and calcium carbonate precipitation. Biological CO2 removal by photosynthesis is identified as the main process to effect pH increase in ponds. The rate of pH increase and consequently the required retention time depend on the net rate of CO2 consumption, the extent of ammonium stripping, the characteristics of the influent (alkalinity and pH) as well as factors concerning the environment (temperature) and dimensions (depth) of the pond. A high pH (range 9 to 10) can be obtained in about 5 days if digested sewage is used (low organic material concentration), climate conditions are favourable and the pond is shallow (< 0.5 m deep).

  2. Intracellular pH in lizard Dipsosaurus dorsalis in relation to changing body temperatures.

    Science.gov (United States)

    Bickler, P E

    1982-12-01

    Mean whole-body and tissue-specific intracellular pH values (pHi) were measured in Dipsosaurus dorsalis by the dimethyloxazolidinedione technique. pHi was measured in lizards at constant body temperatures (Tb) (18, 25, 35, and 42 degrees C) and in lizards undergoing changes in Tb between 18 and 42 degrees C. Constant Tb between 18 and 42 degrees C maintained for 24 h or more produced a delta pH/delta Tb of -0.015 for the mean whole-body, -0.012 for venous blood, -0.0104 for cardiac muscle, and -0.0098 for skeletal muscle. Within the preferred range of Tb values (35-42 degrees C), the delta pH/delta Tb patterns were closer to that expected to achieve constant dissociation of protein imidazole (approximately -0.017): mean whole-body -0.020, cardiac muscle -0.016, and skeletal muscle -0.018. Tissue water contents were independent of Tb. Whole-body pHi during gradual warming and cooling (approximately 2 h elapsed time for each direction) closely corresponded to steady-state values. Upon cooling to 18 degrees C, tissue-specific and whole-body pHi often fell 0.1-0.2 unit below that expected; in each case this was correlated with an extracellular acidosis. A gradual recovery of pHi occurred with the recovery of the extracellular acidosis. Over the normally experienced Tb range, adjustments in pHi apparently rapidly achieve steady-state values and are in accord with the imidazole alphastat hypothesis. These patterns are discussed in terms of the thermal ecology of Dipsosaurus.

  3. Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom Fragilariopsis cylindrus

    DEFF Research Database (Denmark)

    Pancic, Marina; Hansen, Per Juel; Tammilehto, Anna;

    2015-01-01

    Abstract. The effects of ocean acidification and increased temperature on physiology of six strains of the polar diatom Fragilariopsis cylindrus from Greenland were investigated. Experiments were performed under manipulated pH levels (8.0, 7.7, 7.4, and 7.1) and different temperatures (1, 5, and 8...... C) to simulate changes from present to plausible future levels. Each of the 12 scenarios was run for 7 days, and a significant interaction between temperature and pH on growth was detected. By combining increased temperature and acidification, the two factors counterbalanced each other...... the strains was larger than the variation observed due to the whole range of changes in either pH or temperature. Climate change may therefore not affect the species as such, but may lead to changes in the population structure of the species, with the strains exhibiting high phenotypic plasticity, in terms...

  4. Habit-associated salivary pH changes in oral submucous fibrosis-A controlled cross-sectional study

    Directory of Open Access Journals (Sweden)

    Mandana Donoghue

    2015-01-01

    Full Text Available Context: Oral submucous fibrosis (OSF is a multi-causal inflammatory reaction to the chemical or mechanical trauma caused due to exposure to arecanut containing products with or without tobacco (ANCP/T. Arecanut and additional components such as lime and chewing tobacco render ANCP/T highly alkaline. Fibrosing repair is a common reaction to an alkaline exposure in the skin. OSF may be related to the alkaline exposure by ANCP/T in a similar manner. Aims: The study was aimed at establishing the relationship of habit-associated salivary pH changes and OSF. Settings and Design: The study design was controlled cross-sectional. Materials and Methods: Base line salivary pH (BLS pH, salivary pH after chewing the habitual ANCP/T substance, post chew salivary pH (PCSpH for 2 min and salivary pH recovery time (SpHRT were compared in 30 OSF patients and 30 sex-matched individuals with ANCP/T habits and apparently healthy oral mucosa. Results: The group′s mean BLSpH values were similar and within normal range and representative of the population level values. The average PCSpH was significantly higher (P ˂ 0.0001 than the average BLSpH in both groups. There was no significant difference (P = 0.09 between PCSpH of OSF patients and controls. OSF patients had a significantly longer (P = 0.0076 SpHRT than controls. Factors such as age, daily exposure, cumulative habit years, BLSpH and PCSpH, had varying effects on the groups. Conclusions: Chewing ANCP/T causes a significant rise in salivary pH of all individuals. SpHRT has a significant association with OSF. The effect of salivary changes in OSF patients differs with those in healthy controls.

  5. Absolute gravimetry - for monitoring climate change and geodynamics in Greenland

    DEFF Research Database (Denmark)

    Nielsen, Jens Emil

    with the GPS data, it is possible to separate the different signals. The method used in this study is absolute gravimetry. An absolute gravimeter of the A10 type has been purchased by DTU Space for this purpose. This instrument can measure gravity changes as small as 6µGal (= 60nm=s2), which provides....... The time allocated for a PhD project is not sufficient to gather enough data for an elaborated analysis of the different signals which can be detected in Greenland. However, as will be presented in this thesis, the preliminary results indicate interesting possibilities for the use of absolute gravimetry...

  6. The Possible "Proton Sponge " Effect of Polyethylenimine (PEI) Does Not Include Change in Lysosomal pH

    DEFF Research Database (Denmark)

    Søndergaard, Rikke Vicki; Mattebjerg, Maria Ahlm; Henriksen, Jonas Rosager

    2013-01-01

    " hypothesis. Our measurements show that PEI does not induce change in lysosomal pH as previously suggested and quantification of PEI concentrations in lysosomes makes it uncertain that the "proton sponge " effect is the dominant mechanism of polyplex escape.Molecular Therapy (2012); doi:10.1038/mt.2012.185....

  7. Stopped-flow studies of spectral changes in human serum albumin following an alkaline pH jump

    DEFF Research Database (Denmark)

    Honoré, B

    1987-01-01

    A stopped-flow technique was used to study the spectral changes occurring in albumin following a pH jump from 11.3 to 11.8 at 25 degrees C. Ultraviolet difference spectra between various albumin species participating in the process are reported. These spectra are similar in shape to the differenc...

  8. Change in salivary pH following use of homeopathic medicines: A preliminary study

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2013-01-01

    Full Text Available Objective: Homeopathic preparations are popular and well accepted by parents and children. These preparations are easily available and are prescribed for acute and chronic conditions. However, their sugar content may affect oral health. Aims and Objectives: This preliminary study assessed salivary pH following administration of homeopathic medicines commonly prescribed for children. Materials and Methods: Forty-five normal and healthy children were divided into 3 groups of 15 children each: Group 1 was given a placebo, group 2 was given chamomilla (2x, and group 3 was given arsenicum (2x. Each child was given 2 pellets to be placed below the tongue and allowed to dissolve completely. Unstimulated saliva samples were collected at baseline, and following 5, 15, 30, and 60 minutes of administration. The saliva samples were suitably transferred to the laboratory for recording of pH using a digital pH meter. The titratable acidity of both homeopathic medicines was assessed. Data was subjected to statistical analysis. Results: Mean salivary pH at 15 minutes was 5.40 in group 1, 5.16 in group 2 and 5.42 in group 3, which was significant. (P=0.000 At 30 and 60 minutes, pH in groups 2 and 3 remained lower than that of group 1. The titratable acidity of chamomilla and arsenicum was found to be 0.14 mmol and 0.018 mmol, respectively. Conclusion: There was a significant reduction in salivary pH at 5, 15, and 30 minutes in groups 1 and 2. In all groups, salivary pH did not return to baseline values even after one hour of administering the homeopathic pellets.

  9. pH- and Electro-Responsive Properties of Poly(acrylic acid) and Poly(acrylic acid)-block-poly(acrylic acid-grad-styrene) Brushes Studied by Quartz Crystal Microbalance with Dissipation Monitoring.

    Science.gov (United States)

    Borisova, O V; Billon, L; Richter, R P; Reimhult, E; Borisov, O V

    2015-07-14

    We report on the synthesis of novel pH- and electro-responsive polyelectrolyte brushes from a gold substrate by direct one-step nitroxide-mediated polymerization of acrylic acid (AA) or copolymerization of AA and styrene (S). In the latter case, amphiphilic brushes of block-gradient copolymers PAA-b-(PAA-grad-PS) comprising one PAA block and one block with the gradient sequence of AA and S were obtained. The block-gradient copolymers are initiated from the surface by the start of the PAA block. The brushes were characterized by XPS and ellipsometry. (1)H NMR confirmed the gradient sequence of the PAA-grad-PS copolymer block. The pH- and electro-responsive properties of the brushes were studied by quartz crystal microbalance with dissipation monitoring (QCM-D) in combination with electrochemistry. This method provides evidence of swelling of the PAA brushes proportional to the contour length of the chains at elevated pH, whereas the response functions of the block-gradient copolymers are more complex and point to intermolecular aggregation in the brush at low pH. Monitoring of the changes in resonance frequency and dissipation of the QCM-D also demonstrates that application of negative voltage to the substrate leads to swelling of the brush; application of a positive voltage provokes only a transient collapse of the brush in proportion to the applied voltage.

  10. Technical note: A comparison of reticular and ruminal pH monitored continuously with 2 measurement systems at different weeks of early lactation.

    Science.gov (United States)

    Falk, M; Münger, A; Dohme-Meier, F

    2016-03-01

    Subacute ruminal acidosis is one of the most important digestive disorders in high-yielding dairy cows fed highly fermentable diets. Monitoring of forestomach pH has been suggested as a potentially valuable tool for diagnosing subacute ruminal acidosis. The objective of the present study was to compare continuously recorded measurements of an indwelling telemetric pH sensor inserted orally in the reticulum with those obtained from a measurement system placed in the ventral sac of the rumen through a cannula. The experiment was conducted with 6 ruminally cannulated Holstein cows kept in a freestall barn. Equal numbers of cows were assigned to 2 treatment groups based on their previous lactation milk yield. Cows in treatment CON- were offered a diet consisting of only fresh herbage cut once daily, and cows in treatment CON+ got fresh herbage plus a concentrate supplement according to the individual milk yield of each cow to meet their predicted nutrient requirements. The experiment lasted from 2 wk before the predicted calving date until wk 8 of lactation. During the whole experiment, a pH value was recorded every 10 min in the reticulum using a wireless telemetry bolus including a pH sensor (eBolus, eCow Ltd., Exeter, Devon, UK), which had been applied orally using a balling gun. Simultaneously, in wk 2, before the estimated calving date and in wk 2, 4, 6, and 8 of lactation, the ruminal pH was measured every 30 s for 48 h with the LRCpH measurement system (Dascor Inc., Escondido, CA) placed in the ventral sac of the rumen through the cannula. The readings of the LRCpH measurement system were summarized as an average over 10 min for statistical analysis. The recorded pH values were on average 0.24 pH units higher in the reticulum than in the rumen. The reticular pH also showed less fluctuation (overall SD 0.19 pH units) than pH profiles recorded in the rumen (overall SD 0.51 pH units). Regardless of measurement system, pH was not influenced by treatment, but varied

  11. Perioperative ruminal pH changes in domestic sheep (Ovis aries) housed in a biomedical research setting.

    Science.gov (United States)

    Jasmin, Bambi H; Boston, Ray C; Modesto, Rolf B; Schaer, Thomas P

    2011-01-01

    Little information is available on normal ruminal pH values for domestic sheep (Ovis aries) housed in a research setting and fed a complete pelleted ration. Sheep maintained on pelleted diets undergoing surgical procedures often present with postoperative anorexia and rumen atony. To determine the relationship between diet and postoperative rumen acidosis and associated atony, we studied dietary effects on ruminal pH in an ovine surgical model. Sheep undergoing orthopedic surgical procedures were randomized into 2 diet groups. Group 1 (n = 6) was fed complete pelleted diet during the pre- and postoperative period, and group 2 (n = 6) was fed timothy grass hay exclusively throughout the study. Measures included ruminal pH, ruminal motility, and rate of feed refusal, which was monitored throughout the pre- and postoperative periods. The 2 groups did not differ significantly before surgery, and the ruminal parameters remained largely within normal limits. However, a downward trend in the strength and frequency of rumen contractions was observed in pellet-fed sheep. After surgery, the pellet-fed group showed clinical signs consistent with ruminal acidosis, supported by decreased ruminal motility, anorexia, putrid-smelling ruminal material, and death of ruminal protozoa. Intervention by transfaunation in clinically affected sheep resulted in resolution of signs. Our findings suggest that sheep fed grass hay appear to have a more stable ruminal pH, are less likely to experience anorexia and rumen atony, and thereby exhibit fewer postoperative gastrointestinal complications than do sheep on a pellet diet.

  12. Wood Ash Induced pH Changes Strongly Affect Soil Bacterial Numbers and Community Composition

    DEFF Research Database (Denmark)

    Bang-Andreasen, Toke; Nielsen, Jeppe T; Voriskova, Jana

    2017-01-01

    -neutralizing capabilities. However, wood ash has several ecosystem-perturbing effects like increased soil pH and pore water electrical conductivity both known to strongly impact soil bacterial numbers and community composition. Studies investigating soil bacterial community responses to wood ash application remain sparse...... and sporeforming bacteria combined with 16S rRNA gene amplicon sequencing to valuate soil bacterial responses to wood ash application. Results showed that wood ash addition strongly increased soil pH and electrical conductivity. Soil pH increased from acidic through neutral at 22 t ha(-1) to alkaline at 167 t ha......Recirculation of wood ash from energy production to forest soil improves the sustainability of this energy production form as recycled wood ash contains nutrients that otherwise would be lost at harvest. In addition, wood-ash is beneficial to many soils due to its inherent acid...

  13. Wood Ash Induced pH Changes Strongly Affect Soil Bacterial Numbers and Community Composition

    DEFF Research Database (Denmark)

    Bang-Andreasen, Toke; Nielsen, Jeppe T.; Voriskova, Jana

    2017-01-01

    and sporeforming bacteria combined with 16S rRNA gene amplicon sequencing to valuate soil bacterial responses to wood ash application. Results showed that wood ash addition strongly increased soil pH and electrical conductivity. Soil pH increased from acidic through neutral at 22 t ha(-1) to alkaline at 167 t ha......-neutralizing capabilities. However, wood ash has several ecosystem-perturbing effects like increased soil pH and pore water electrical conductivity both known to strongly impact soil bacterial numbers and community composition. Studies investigating soil bacterial community responses to wood ash application remain sparse...... and the available results are ambiguous and remain at a general taxonomic level. Here we investigate the response of bacterial communities in a spruce forest soil to wood ash addition corresponding to 0, 5, 22, and 167 t wood ash ha(-1). We used culture-based enumerations of general bacteria, Pseudomonas...

  14. Sensitive change detection for remote sensing monitoring of nuclear treaties

    DEFF Research Database (Denmark)

    Canty, Morton J.; Nielsen, Allan Aasbjerg; Schlittenhardt, Jörg

    2005-01-01

    or uninteresting changes, see e.g. (Canty and Schlittenhardt 2001). In our contribution we focus attention on the use of conventional multispectral earth observation satellite platforms with moderate ground resolution (Landsat TM, ASTER, SPOT) to detect changes over wide areas which are relevant to nuclear non......Triggered in part by the advent of high resolution commercial optical satellites, the analysis of open-source satellite imagery has now established itself as an important tool for monitoring nuclear activities throughout the world (Chitumbo et al 2001). Whereas detection of land cover and land use...... the framework of the Global Monitoring for Security and Stability Network of Excellence (GMOSS) initiated by the European Commission. Chitumbo, K., Robb, S., Bunney, J. and Lev\\$\\backslash\\$'e, G., IAEA Satellite imagery and the Department of Safeguards, Proceedings of the Symposium on International Safeguards...

  15. Science PhD career preferences: levels, changes, and advisor encouragement.

    Directory of Open Access Journals (Sweden)

    Henry Sauermann

    Full Text Available Even though academic research is often viewed as the preferred career path for PhD trained scientists, most U.S. graduates enter careers in industry, government, or "alternative careers." There has been a growing concern that these career patterns reflect fundamental imbalances between the supply of scientists seeking academic positions and the availability of such positions. However, while government statistics provide insights into realized career transitions, there is little systematic data on scientists' career preferences and thus on the degree to which there is a mismatch between observed career paths and scientists' preferences. Moreover, we lack systematic evidence whether career preferences adjust over the course of the PhD training and to what extent advisors exacerbate imbalances by encouraging their students to pursue academic positions. Based on a national survey of PhD students at tier-one U.S. institutions, we provide insights into the career preferences of junior scientists across the life sciences, physics, and chemistry. We also show that the attractiveness of academic careers decreases significantly over the course of the PhD program, despite the fact that advisors strongly encourage academic careers over non-academic careers. Our data provide an empirical basis for common concerns regarding labor market imbalances. Our results also suggest the need for mechanisms that provide PhD applicants with information that allows them to carefully weigh the costs and benefits of pursuing a PhD, as well as for mechanisms that complement the job market advice advisors give to their current students.

  16. Bravo capsule system optimizes intragastric pH monitoring over prolonged time: Effects of ghrelin on gastric acid and hormone secretion in the rat

    Institute of Scientific and Technical Information of China (English)

    Tobias Rudholm; Per Mikael Hellstrom; Elvar Theodorsson; Colin Allan Campbell; Peter Geoffrey McLean; Erik Naslund

    2008-01-01

    AIM: To evaluate measurements of intragastric pH with the Bravo capsule system over a prolonged time. METHODS: A Bravo capsule was placed inside the rat gastric body and pH was studied for periods up to five consecutive days. For comparison, a gastric fistula model was used. Effects of ghrelin and esomeprazole, with or without pentagastrin, on gastric pH were studied. In addition, effects of esomeprazole on plasma ghrelin, gastrin and somatostatin were analyzed. RESULTS: All rats recovered after surgery. The average 24-h pH during free feeding was 2.3±0.1 (η = 20) with a variation of 18%±6% over 5 d. Ghrelin, 2400 pmol/kg, t.i.d, increased pH from 1.7± 0.1 to 3.1±0.3 (P<0.01) as recorded with the Bravo system. After esomeprazole (1 mg/kg, 3 mg/kg and 5 mg/kg) there was a dose-dependent pH increase of maximally 3.4±0.1, with day-to-day variation over the entire period of 8%±3%. The fistula and pH studies generated similar results. Acid inhibition with esomeprazole increased plasma ghrelin from 10±2 pmol/L to 65±26 pmol/L (P<0.001), and somatostatin from 10±2 pmol/L to 67±18 pmol/L (P <0.001). CONCLUSION: pH measurements with the Bravo capsule are reliable, and comparable to those of the gastric fistula model. The Bravo system optimizes accurate intragastric pH monitoring over prolonged periods and allows both short- and long-term evaluation of effects of drugs and hormones.

  17. Overview of the Existing Forest Area Changes Monitoring Systems

    OpenAIRE

    Achard, Frederic; DeFries, Ruth; Pandey, Devendra; Souza, Carlos

    2009-01-01

    This chapter presents an overview of the existing forest area changes monitoring systems at the national scale in tropical countries using remote sensing imagery. Section 3.2.2 describes national case studies: the Brazilian system which produces annual estimates of deforestation in the legal Amazon, the Indian National biannual forest cover assessment, an example of a sampling approach in the Congo basin and an example of wall-to-wall approach in Cameroon.

  18. The ecology of acidification and recovery: changes in herbivore-algal food web linkages across a stream pH gradient

    Energy Technology Data Exchange (ETDEWEB)

    Ledger, M.E. [Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom)]. E-mail: m.e.ledger@bham.ac.uk; Hildrew, A.G. [Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom)

    2005-09-15

    We examined the effects of acidification on herbivore-algal food web linkages in headwater streams. We determined the structure and abundance of consumer and benthic algal assemblages, and gauged herbivory, in 10 streams along a pH gradient (mean annual pH 4.6-6.4). Biofilm taxonomic composition changed with pH but total abundance did not vary systematically across the gradient. Mayflies and chironomids dominated under circumneutral conditions but declined with increasing acidity and their consumption of algae was strongly reduced. Contrary to expectations, several putative shredder species consumed algae, maintaining the herbivore-algal linkage where specialist grazers could not persist. These shifts in functioning could render the communities of acidified streams resistant to reinvasion when acidity ameliorates and water chemistry is restored to a pre-acidification condition. This hypothesis is discussed in the light of recent trends in the chemistry and biology of the UK Acid Waters Monitoring Network sites. - Generalist invertebrates maintain algae-herbivore interactions in acid streams.

  19. Anacardic acid-mediated changes in membrane potential and pH gradient across liposomal membranes.

    Science.gov (United States)

    Toyomizu, Masaaki; Okamoto, Katsuyuki; Akiba, Yukio; Nakatsu, Tetsuo; Konishi, Tetsuya

    2002-01-01

    We have previously shown that anacardic acid has an uncoupling effect on oxidative phosphorylation in rat liver mitochondria using succinate as a substrate (Life Sci. 66 (2000) 229-234). In the present study, for clarification of the physicochemical characteristics of anacardic acid, we used a cyanine dye (DiS-C3(5)) and 9-aminoacridine (9-AA) to determine changes of membrane potential (DeltaPsi) and pH difference (DeltapH), respectively, in a liposome suspension in response to the addition of anacardic acid to the suspension. The anacardic acid quenched DiS-C3(5) fluorescence at concentrations higher than 300 nM, with the degree of quenching being dependent on the log concentration of the acid. Furthermore, the K(+) diffusion potential generated by the addition of valinomycin to the suspension decreased for each increase in anacardic acid concentration used over 300 nM, but the sum of the anacardic acid- and valinomycin-mediated quenching was additively increasing. This indicates that the anacardic acid-mediated quenching was not due simply to increments in the K(+) permeability of the membrane. Addition of anacardic acid in the micromolar range to the liposomes with DeltaPsi formed by valinomycin-K(+) did not significantly alter 9-AA fluorescence, but unexpectedly dissipated DeltaPsi. The DeltaPsi preformed by valinomycin-K(+) decreased gradually following the addition of increasing concentrations of anacardic acid. The DeltaPsi dissipation rate was dependent on the pre-existing magnitude of DeltaPsi, and was correlated with the logarithmic concentration of anacardic acid. Furthermore, the initial rate of DeltapH dissipation increased with logarithmic increases in anacardic acid concentration. These results provide the evidence for a unique function of anacardic acid, dissimilar to carbonylcyanide p-trifluoromethoxyphenylhydrazone or valinomycin, in that anacardic acid behaves as both an electrogenic (negative) charge carrier driven by DeltaPsi, and a 'proton

  20. Raman microspectroscopic study of effects of Na(I) and Mg(II) ions on low pH induced DNA structural changes

    NARCIS (Netherlands)

    Muntean, C.M.; Segers-Nolten, G.M.J.

    2003-01-01

    In this work a confocal Raman microspectrometer is used to investigate the influence of Na+ and Mg2+ ions on the DNA structural changes induced by low pH. Measurements are carried out on calf thymus DNA at neutral pH (7) and pH 3 in the presence of low and high concentrations of Na+ and Mg2+ ions, r

  1. Cell wall composition of Bacillus subtilis changes as a function of pH and Zn²⁺ exposure: insights from cryo-XPS measurements.

    Science.gov (United States)

    Ramstedt, Madeleine; Leone, Laura; Persson, Per; Shchukarev, Andrey

    2014-04-22

    Bacteria play an important role in the biogeochemical cycling of metals in the environment. Consequently, there is an interest to understand how the bacterial surfaces interact with metals in solution and how this affects the bacterial surface. In this work we have used a surface-sensitive analysis technique, cryogenic X-ray photoelectron spectroscopy (cryo-XPS), to monitor the surface of Bacillus subtilis cells as a function of pH and Zn(2+) content in saline solution. The objective of the study was twofold: (1) to investigate the agreement between two data treatment methods for XPS, as well as investigate to what extent sample pretreatment may influence XPS data of bacterial samples, and (2) to characterize how the surface chemistry of bacterial cells is influenced by different external conditions. (1) It was found that the two data treatment methods gave rise to comparable results. However, identical samples analyzed fast-frozen or dry exhibited larger differences in surface chemistry, indicating that sample pretreatment can to large extents influence the obtained surface composition of bacterial samples. (2) The bacterial cell wall (in fast-frozen samples) undergoes dramatic compositional changes with pH and with Zn(2+) exposure. The compositional changes are interpreted as an adaptive metal resistance response changing the biochemical composition of the bacterial cell wall. These results have implications for how adsorption processes at the surface of bacterial cells are analyzed, understood, modeled, and predicted.

  2. Drought Monitoring, Prediction and Adaptation under Climatic Changes

    Science.gov (United States)

    Su, Z.; Ma, Y.; van der Velde, R.; Dente, L.; Wang, L.; Timmermans, J.; Menenti, M.; Sobrino, J.; Li, Z.-L.; Verhoef, W.; Jia, L.; Wen, J.; He, Y.; Wan, L.; Liu, Q. H.; Yu, Q.; Li, X.; Zhong, L.; Zeng, Y.; Tian, X.; Li, L.; Qin, C.; Timmermans, W.; van Helvoirt, M.; van der Tol, C.; Salama, M. S.; Vekerdy, Z.

    2013-01-01

    The objective of this project was to develop a quantitative and operational system for nationwide drought monitoring and drought impact assessment for application in agriculture and water resources and environment in China using ESA, Chinese and other relevant satellite data as major data source in combination with other data (e.g. meteorological and drought statistics, etc.). An extension to drought prediction and adaptation to climate change had been made compared to the Dragon I drought monitoring project. In detail the project generated: (1) a preoperational real time drought monitoring and prediction system, (2) improved understanding of land surface processes and land-atmosphere interactions over different terrains (e.g. agriculture land, forest, Gobi desert, high plateau, polar environment), (3) algorithms for estimation of land surface parameters and heat fluxes, (4) assessment of economic loss caused by drought and adaptation measures under climatic change, (5) training of young scientists in the area of water, climate and environment. An operational system will be established by the China Meteorological Administration’s National Meteorological Center (CMA/NMC) to provide information concerning the drought evolution situation and to support drought relief decision-making. We report on advances in retrievals of soil moisture using in-situ observations, satellite sensors and numerical modeling. The accuracy of available soil moisture products are assessed using in-situ data collected in the soil moisture monitoring networks developed for this and other projects. The use of these satellite retrievals in drought monitoring is demonstrated by analyzing the droughts in China and the generated drought assessment indices are compared to current practice by CMA.

  3. Factors affecting pH change in alkaline waste water treatment - II: Carbon dioxide production

    NARCIS (Netherlands)

    Lijklema, L.

    1971-01-01

    The carbon dioxide produced during biological oxidation of wastewater has a pronounced influence upon the pH that is attained in the activated sludge process. The quantity produced is proportional to the COD removed, its degree of oxidation and depends also on the oxidation level of the substrate. A

  4. Long-term effects of water pH changes on hematological parameters ...

    African Journals Online (AJOL)

    Yomi

    2012-02-14

    Feb 14, 2012 ... face between fish and its environment for gas transfer, acid-base ... and low water pH on ion balance and ammonia excretion in freshwater fish ... Water quality parameters of the stored water were measured at the beginning of ...

  5. Research on Monitoring Area Division of Quality Grade Changes in County Cultivated Land and Technology of Deploying Monitoring Point

    Institute of Scientific and Technical Information of China (English)

    Wei; WEI; Lijun; LIAO; Jianxin; YU

    2013-01-01

    It is an important means in management of improving both the quality and quantity of cultivated land to monitor grade changes in cultivated land quality. How to deploy monitoring network system and its point reasonably and roundly are the key to the technology of monitoring grade changes in cultivated land quality by monitoring grade changes in cultivated land quality dynamically in order to obtain the information to the index of cultivated land quality and its changes based on the existing achievements of farmland classification and grading. Spatial analysis method is used to demarcate monitoring area and deploy monitoring point according to ARCGIS,of which the result can meet the demand for monitoring grade changes in cultivated land.

  6. SCALABLE TIME SERIES CHANGE DETECTION FOR BIOMASS MONITORING USING GAUSSIAN PROCESS

    Data.gov (United States)

    National Aeronautics and Space Administration — SCALABLE TIME SERIES CHANGE DETECTION FOR BIOMASS MONITORING USING GAUSSIAN PROCESS VARUN CHANDOLA AND RANGA RAJU VATSAVAI Abstract. Biomass monitoring,...

  7. Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom Fragilariopsis cylindrus

    Directory of Open Access Journals (Sweden)

    M. Pančić

    2015-03-01

    Full Text Available The effects of ocean acidification and increased temperature on physiology of six strains of the polar diatom Fragilariopsis cylindrus from Greenland were investigated. Experiments were performed under manipulated pH levels (8.0, 7.7, 7.4, and 7.1 and different temperatures (1, 5 and 8 °C to simulate changes from present to plausible future levels. Each of the 12 scenarios was run for 7 days, and a significant interaction between temperature and pH on growth was detected. By combining increased temperature and acidification, the two factors counterbalanced each other, and therefore no effect on the growth rates was found. However, the growth rates increased with elevated temperatures by ∼20–50% depending on the strain. In addition, a general negative effect of increasing acidification on growth was observed. At pH 7.7 and 7.4, the growth response varied considerably among strains. However, a more uniform response was detected at pH 7.1 with most of the strains exhibiting reduced growth rates by 20–37% compared to pH 8.0. It should be emphasized that a significant interaction between temperature and pH was found, meaning that the combination of the two parameters affected growth differently than when considering one at a time. Based on these results, we anticipate that the polar diatom F. cylindrus will be unaffected by changes in temperature and pH within the range expected by the end of the century. In each simulated scenario, the variation in growth rates among the strains was larger than the variation observed due to the whole range of changes in either pH or temperature. Climate change may therefore not affect the species as such, but may lead to changes in the population structure of the species, with the strains exhibiting high phenotypic plasticity, in terms of temperature and pH tolerance towards future conditions, dominating the population.

  8. Halocarbon emissions by selected tropical seaweeds: species-specific and compound-specific responses under changing pH

    Science.gov (United States)

    Leedham Elvidge, Emma C.; Sturges, William T.; Malin, Gill; Abd Rahman, Noorsaadah

    2017-01-01

    Five tropical seaweeds, Kappaphycus alvarezii (Doty) Doty ex P.C. Silva, Padina australis Hauck, Sargassum binderi Sonder ex J. Agardh (syn. S. aquifolium (Turner) C. Agardh), Sargassum siliquosum J. Agardh and Turbinaria conoides (J. Agardh) Kützing, were incubated in seawater of pH 8.0, 7.8 (ambient), 7.6, 7.4 and 7.2, to study the effects of changing seawater pH on halocarbon emissions. Eight halocarbon species known to be emitted by seaweeds were investigated: bromoform (CHBr3), dibro­momethane (CH2Br2), iodomethane (CH3I), diiodomethane (CH2I2), bromoiodomethane (CH2BrI), bromochlorometh­ane (CH2BrCl), bromodichloromethane (CHBrCl2), and dibro­mochloromethane (CHBr2Cl). These very short-lived halocarbon gases are believed to contribute to stratospheric halogen concentrations if released in the tropics. It was observed that the seaweeds emit all eight halocarbons assayed, with the exception of K. alvarezii and S. binderi for CH2I2 and CH3I respectively, which were not measurable at the achievable limit of detection. The effect of pH on halocarbon emission by the seaweeds was shown to be species-specific and compound specific. The highest percentage changes in emissions for the halocarbons of interest were observed at the lower pH levels of 7.2 and 7.4 especially in Padina australis and Sargassum spp., showing that lower seawater pH causes elevated emissions of some halocarbon compounds. In general the seaweed least affected by pH change in terms of types of halocarbon emission, was P. australis. The commercially farmed seaweed K. alvarezii was very sensitive to pH change as shown by the high increases in most of the compounds in all pH levels relative to ambient. In terms of percentage decrease in maximum quantum yield of photosynthesis (Fv∕Fm) prior to and after incubation, there were no significant correlations with the various pH levels tested for all seaweeds. The correlation between percentage decrease in the maximum quantum yield of photosynthesis

  9. Halocarbon emissions by selected tropical seaweeds: species-specific and compound-specific responses under changing pH

    Directory of Open Access Journals (Sweden)

    Paramjeet Kaur Mithoo-Singh

    2017-01-01

    Full Text Available Five tropical seaweeds, Kappaphycus alvarezii (Doty Doty ex P.C. Silva, Padina australis Hauck, Sargassum binderi Sonder ex J. Agardh (syn. S. aquifolium (Turner C. Agardh, Sargassum siliquosum J. Agardh and Turbinaria conoides (J. Agardh Kützing, were incubated in seawater of pH 8.0, 7.8 (ambient, 7.6, 7.4 and 7.2, to study the effects of changing seawater pH on halocarbon emissions. Eight halocarbon species known to be emitted by seaweeds were investigated: bromoform (CHBr3, dibro­momethane (CH2Br2, iodomethane (CH3I, diiodomethane (CH2I2, bromoiodomethane (CH2BrI, bromochlorometh­ane (CH2BrCl, bromodichloromethane (CHBrCl2, and dibro­mochloromethane (CHBr2Cl. These very short-lived halocarbon gases are believed to contribute to stratospheric halogen concentrations if released in the tropics. It was observed that the seaweeds emit all eight halocarbons assayed, with the exception of K. alvarezii and S. binderi for CH2I2 and CH3I respectively, which were not measurable at the achievable limit of detection. The effect of pH on halocarbon emission by the seaweeds was shown to be species-specific and compound specific. The highest percentage changes in emissions for the halocarbons of interest were observed at the lower pH levels of 7.2 and 7.4 especially in Padina australis and Sargassum spp., showing that lower seawater pH causes elevated emissions of some halocarbon compounds. In general the seaweed least affected by pH change in terms of types of halocarbon emission, was P. australis. The commercially farmed seaweed K. alvarezii was very sensitive to pH change as shown by the high increases in most of the compounds in all pH levels relative to ambient. In terms of percentage decrease in maximum quantum yield of photosynthesis (Fv∕Fm prior to and after incubation, there were no significant correlations with the various pH levels tested for all seaweeds. The correlation between percentage decrease in the maximum quantum yield of

  10. Stationary monitoring of glacier response to climate change in China

    Science.gov (United States)

    Ren, Jiawen; Li, Zhongqin; Qin, Xiang; He, Yuanqing; He, Xiaobo; Li, Huilin

    2016-04-01

    At present, there are about 48571 glaciers with a total area of about 51.8×103 km2 and a volume of about 5.6×103 km3 in China. They are distributed widely in the high mountains in and surrounding the Tibetan Plateau and other high mountains such as Tianshan, Altay and Pamir. In view of differences in climatic conditions and glacier types, stationary monitoring of the glacier variations has been ongoing in different regions in order to investigate the glacier response to climate change. The monitoring results show that all the monitoring glaciers have been in retreat during the past decades and especially since 1990's the retreat rate has an accelerating trend. The accumulative mass balance is much negative and has a large annual variability for the monsoonal maritime glaciers in comparison with the continental and sub-continental glaciers. Under climate warming background, the acceleration of glacier melting is mainly attributed to rise in air temperature, ice temperature augment and albedo reduction of glacier surface. Particularly, the albedo reduction has a positive feedback effect on the glacier melting. Based on long term observation of glacier variations and physical properties, a simple dynamics model is coupled with mass balance modeling to make a projection of a typical glacier change in future. The primary modeling results suggest that the glacier will continue in shrinkage until vanishing within 50-90 years.

  11. Defining functional biomes and monitoring their change globally.

    Science.gov (United States)

    Higgins, Steven I; Buitenwerf, Robert; Moncrieff, Glenn R

    2016-11-01

    Biomes are important constructs for organizing understanding of how the worlds' major terrestrial ecosystems differ from one another and for monitoring change in these ecosystems. Yet existing biome classification schemes have been criticized for being overly subjective and for explicitly or implicitly invoking climate. We propose a new biome map and classification scheme that uses information on (i) an index of vegetation productivity, (ii) whether the minimum of vegetation activity is in the driest or coldest part of the year, and (iii) vegetation height. Although biomes produced on the basis of this classification show a strong spatial coherence, they show little congruence with existing biome classification schemes. Our biome map provides an alternative classification scheme for comparing the biogeochemical rates of terrestrial ecosystems. We use this new biome classification scheme to analyse the patterns of biome change observed over recent decades. Overall, 13% to 14% of analysed pixels shifted in biome state over the 30-year study period. A wide range of biome transitions were observed. For example, biomes with tall vegetation and minimum vegetation activity in the cold season shifted to higher productivity biome states. Biomes with short vegetation and low seasonality shifted to seasonally moisture-limited biome states. Our findings and method provide a new source of data for rigorously monitoring global vegetation change, analysing drivers of vegetation change and for benchmarking models of terrestrial ecosystem function. © 2016 John Wiley & Sons Ltd.

  12. Positively charged and pH self-buffering quantum dots for efficient cellular uptake by charge mediation and monitoring cell membrane permeability

    Energy Technology Data Exchange (ETDEWEB)

    Wang Suhua; Song Haipeng; Huang Dejian [Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 (Singapore); Ong Weiyi [Department of Anatomy, National University of Singapore, 119260 (Singapore); Han Mingyong, E-mail: chmhdj@nus.edu.s [Institute of Materials Research and Engineering, 3 Research Link, 117602 (Singapore)

    2009-10-21

    Positively charged and pH self-buffering quantum dots (Tren-QDs) were achieved by surface functionalization with tris(2-aminoethyl)amine (Tren) derivatives, which are attached to the inorganic cores of QDs through bidentate chelating of dithiocarbamates. The Tren-QDs exhibit pH buffering capability by absorbing or releasing protons due to the surface polyamine groups as the surrounding pH fluctuates. Such self-buffering capability stabilizes the photoluminescence of the Tren-QDs against acid. The Tren-QDs bear positive charges through protonation of the surface polyamine groups under physiological conditions and the surface positive charges improve their cellular uptake efficiency by charge mediation, which has been demonstrated by BV-2 microglia cells. The photoluminescence of Tren-QDs shows a selective Stern-Volmer response to copper ions and this property has been preliminarily evaluated for investigating the BV-2 cell membrane structure by monitoring the photoluminescence of intracellular Tren-QDs.

  13. Positively charged and pH self-buffering quantum dots for efficient cellular uptake by charge mediation and monitoring cell membrane permeability

    Science.gov (United States)

    Wang, Suhua; Song, Haipeng; Ong, Wei Yi; Han, Ming Yong; Huang, Dejian

    2009-10-01

    Positively charged and pH self-buffering quantum dots (Tren-QDs) were achieved by surface functionalization with tris(2-aminoethyl)amine (Tren) derivatives, which are attached to the inorganic cores of QDs through bidentate chelating of dithiocarbamates. The Tren-QDs exhibit pH buffering capability by absorbing or releasing protons due to the surface polyamine groups as the surrounding pH fluctuates. Such self-buffering capability stabilizes the photoluminescence of the Tren-QDs against acid. The Tren-QDs bear positive charges through protonation of the surface polyamine groups under physiological conditions and the surface positive charges improve their cellular uptake efficiency by charge mediation, which has been demonstrated by BV-2 microglia cells. The photoluminescence of Tren-QDs shows a selective Stern-Volmer response to copper ions and this property has been preliminarily evaluated for investigating the BV-2 cell membrane structure by monitoring the photoluminescence of intracellular Tren-QDs.

  14. Conformational changes in human serum albumin studied by fluorescence and absorption spectroscopy. Distance measurements as a function of pH and fatty acids

    DEFF Research Database (Denmark)

    Honoré, B; Pedersen, A O

    1989-01-01

    pH- and fatty acid-induced conformational changes in human serum albumin were investigated by fluorescence-energy transfer, determining the distance between Trp-214 and bound bilirubin at 25 degrees C. This distance changes significantly with the pH, being 2.52 +/- 0.01 nm at pH 6, 2.31 +/- 0.04 ...... chromophores. The contraction of the protein carrying long-chain saturated fatty acids is even more pronounced at pH 9. Udgivelsesdato: 1989-Feb-15......pH- and fatty acid-induced conformational changes in human serum albumin were investigated by fluorescence-energy transfer, determining the distance between Trp-214 and bound bilirubin at 25 degrees C. This distance changes significantly with the pH, being 2.52 +/- 0.01 nm at pH 6, 2.31 +/- 0.04 nm...... at pH 9, 2.13 +/- 0.07 nm at pH 11.0 and 2.77 nm at pH 11.9. The influence of different fatty acids on the distance was also determined. At pH 7.4 medium-chain fatty acids seem to increase this distance, whereas long-chain fatty acids, at low concentrations, decrease the distance between the two...

  15. Impact of shear stress and pH changes on floc size and removal of dissolved organic matter (DOM).

    Science.gov (United States)

    Slavik, Irene; Müller, Susanne; Mokosch, Regina; Azongbilla, Joseph Abanga; Uhl, Wolfgang

    2012-12-01

    The impact of shear stress and increases in pH on the release of natural dissolved organic matter (DOM) from Fe-DOM and Al-DOM flocs was investigated for a high organic matter, low turbidity raw water by application of a dynamic extinction probe (DEP) and liquid chromatography organic carbon detection (LC-OCD). It was shown that high shear forces resulted in a breakage of Fe-DOM flocs. Re-growth took place during subsequent low shear phases. However, re-growth was limited. The flocs regained a size of about 50% of the size after initial coagulation. Cyclic shearing resulted in slower re-growth rates. A new insight was that when enough time was given, similar sizes of the re-grown flocs were regained. As shown by bulk DOC, only an insignificant release of DOM took place when flocs were exposed to shear. Increase in shear stress resulted in smaller flocs with higher specific outer surface area. However, DOM removal did not change. Thus, there was no increase in adsorption capacity due to floc breakage. Consequently, DOM must be adsorbed inside the amorphous flocs rather than on the outer surface. Also, as shear results in more compact flocs, compaction does not have an effect on DOM removal. A pH increase of 0.5, as it can happen during water treatment after coagulation, resulted in a release of DOM. Humic substances accounted for the largest proportion of total DOM released. The increase in pH did not affect floc size. Consequently, DOM removal is mainly governed by the dependence of DOM properties on pH with the final pH determining the degree of DOM removal and not the path on which this pH is reached. The physical properties of the flocs have no impact on DOM removal. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Use of 24 h Esophageal pH Monitoring to Demonstrate Alkaline Reflux as a Complication of Gastric Bypass Surgery

    Directory of Open Access Journals (Sweden)

    J Patrick Shoenut

    1994-01-01

    Full Text Available A 35-year-old female who had previously undergone a gastric stapling procedure for morbid obesity presented with a persistent nocturnal cough that was treated over a three-year period as a gastric acid reflux complication of the bypass surgery. A barium swallow demonstrated gastroesophageal reflux, but the symptoms did not resolve after treatment with omeprazole and cisapride. Twenty-four hour esophageal pH monitoring subsequently found alkaline reflux in excess of 17% of the total time, with no acid reflux demonstrated. Surgical revision of the bypass Leaving the hiatus alone corrected the reflux complication and the symptoms resolved without further treatment. The diagnostic capability of pH monitoring is illustrated in a patient with an unusual surgical complication.

  17. Multi-site saturation by OmniChange yields a pH- and thermally improved phytase.

    Science.gov (United States)

    Shivange, Amol V; Dennig, Alexander; Schwaneberg, Ulrich

    2014-01-20

    Directed evolution of Yersinia mollaretii phytase (Ymphytase) yielded an improved variant SM2P3E4 (also named M1; D52N, T77K, K139E, G187S, V298M) in our previous study. Variant M1 retained high specific activity (993U/mg; equivalent to 93% of wild-type activity) and improved thermal resistance (T50 improved by 1.5°C compared to wild-type at 58°C; 20min incubation time), making variant M1 an attractive enzyme for industrial applications. Recently, the OmniChange method was developed for multi-site saturation mutagenesis. The five sites identified in variant M1 were subjected to OmniChange saturation in order to explore whether a variant with higher activity, higher thermal resistance, and higher resistance at low pH (2-3h incubation was performed to mimic the gastric residence time of phytase) could be identified. Screening of a small library of 1100 clones, covering <0.004% of the theoretical sequence space of 3.35×10(7) variants, yielded a Ymphytase variant with 32% improved residual activity (58°C for 20min), 2°C increased apparent melting temperature (Tm), and 2-fold higher pH stability (pH 2.8; 3h incubation time) when compared to the wild-type Ymphytase. Compared to the M1 variant, the pH stability (pH 2.8; 3h incubation time) was improved by 3-fold, and thermal resistance as well as activity was improved slightly (residual activity: 32% compared to 20%; apparent Tm: 2°C compared to 1.5°C; activity difference <4%). Copyright © 2013 Elsevier B.V. All rights reserved.

  18. EXAMINATION OF FACTORS INFLUENCING THE VARIABILITY OF YEAST AMOUNT IN THE CONTEXT OF PH CHANGES IN BOTTLED WINES

    OpenAIRE

    Ladislav Mura; Ľubomír Lopašovský; Dagmar Kozelová; Lucia Zeleňáková; Eva Matejková

    2011-01-01

    Aim of this paper was to examine of factors (manufacturer, temperature and storage time) influencing the variability of yeast amount and pH changes in bottled white wines. It was confirmed that wine coming from the business network was better quality in contract to domestic wine. We have assumed that domestic wine was contaminated during the manufacturing process, while the most probable reason was imperfect filtration of wine, or its contamination during the bottling. The results showed that...

  19. Compartment-specific pH monitoring in Bacillus subtilis using fluorescent sensor proteins; a tool to analyse the antibacterial effect of weak organic acids.

    Directory of Open Access Journals (Sweden)

    Johan W.A. van Beilen

    2013-06-01

    Full Text Available The internal pH (pHi of a living cell is one of its most important physiological parameters. To monitor the pH inside B. subtilis during various stages of its life cycle, we constructed an improved version (IpHluorin of the ratiometric, pH-sensitive fluorescent protein pHluorin by extending it at the 5’ end with the first 24 bp of comGA. The new version, which showed an approximate 40% increase in fluorescence intensity, was expressed from developmental phase-specific, native promoters of B. subtilis that are specifically active during vegetative growth on glucose (PptsG or during sporulation (PspoIIA, PspoIIID and PsspE. Our results show strong, compartment-specific expression of IpHluorin that allowed accurate pHi measurements of live cultures during exponential growth, early and late sporulation, spore germination, and during subsequent spore outgrowth. Dormant spores were characterised by an internal pH of 6.0 ± 0.3. Upon full germination the internal pH rose dependent on the medium to 7.0-7.4. The presence of sorbic acid in the germination medium inhibited a rise in the intracellular pH of germinating spores and inhibited germination. Such effects were absent when acetic was added at identical concentrations.

  20. Towards biochemical filters with a sigmoidal response to pH changes: buffered biocatalytic signal transduction

    Science.gov (United States)

    Pita, Marcos; Privman, Vladimir; Arugula, Mary A.; Melnikov, Dmitriy; Bocharova, Vera; Katz, Evgeny

    We realize a biochemical filtering process by introducing a buffer in a biocatalytic signal-transduction logic system based on the function of an enzyme, esterase. The input, ethyl butyrate, is converted into butyric acid-the output signal, which in turn is measured by the drop in the pH value. The developed approach offers a versatile "network element" for increasing the complexity of biochemical information processing systems. Evaluation of an optimal regime for quality filtering is accomplished in the framework of a kinetic rate-equation model.

  1. Towards biochemical filters with a sigmoidal response to pH changes: buffered biocatalytic signal transduction.

    Science.gov (United States)

    Pita, Marcos; Privman, Vladimir; Arugula, Mary A; Melnikov, Dmitriy; Bocharova, Vera; Katz, Evgeny

    2011-03-14

    We realize a biochemical filtering process by introducing a buffer in a biocatalytic signal-transduction logic system based on the function of an enzyme, esterase. The input, ethyl butyrate, is converted into butyric acid--the output signal, which in turn is measured by the drop in the pH value. The developed approach offers a versatile "network element" for increasing the complexity of biochemical information processing systems. Evaluation of an optimal regime for quality filtering is accomplished in the framework of a kinetic rate-equation model.

  2. Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom Fragilariopsis cylindrus

    DEFF Research Database (Denmark)

    Pancic, Marina; Hansen, Per Juel; Tammilehto, Anna

    2015-01-01

    Abstract. The effects of ocean acidification and increased temperature on physiology of six strains of the polar diatom Fragilariopsis cylindrus from Greenland were investigated. Experiments were performed under manipulated pH levels (8.0, 7.7, 7.4, and 7.1) and different temperatures (1, 5, and 8...... C) to simulate changes from present to plausible future levels. Each of the 12 scenarios was run for 7 days, and a significant interaction between temperature and pH on growth was detected. By combining increased temperature and acidification, the two factors counterbalanced each other......, and therefore no effect on the growth rates was found. However, the growth rates increased with elevated temperatures by 20–50% depending on the strain. In addition, a general negative effect of increasing acidification on growth was observed. At pH 7.7 and 7.4, the growth response varied considerably among...

  3. Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom Fragilariopsis cylindrus

    DEFF Research Database (Denmark)

    Pančić, M.; Hansen, Peter Juul; Tammilehto, A.

    2015-01-01

    The effects of ocean acidification and increased temperature on physiology of six strains of the polar diatom Fragilariopsis cylindrus from Greenland were investigated. Experiments were performed under manipulated pH levels (8.0, 7.7, 7.4, and 7.1) and different temperatures (1, 5 and 8 °C......) to simulate changes from present to plausible future levels. Each of the 12 scenarios was run for 7 days, and a significant interaction between temperature and pH on growth was detected. By combining increased temperature and acidification, the two factors counterbalanced each other, and therefore no effect...... on the growth rates was found. However, the growth rates increased with elevated temperatures by ∼20–50% depending on the strain. In addition, a general negative effect of increasing acidification on growth was observed. At pH 7.7 and 7.4, the growth response varied considerably among strains. However, a more...

  4. Climate Change, Carbon Dioxide, and Pest Biology: Monitor, Mitigate, Manage.

    Science.gov (United States)

    Ziska, Lewis H; McConnell, Laura L

    2016-01-13

    Rising concentrations of atmospheric carbon dioxide ([CO2]) and subsequent changes in climate, including temperature and precipitation extremes, are very likely to alter pest pressures in both managed and unmanaged plant communities. Such changes in pest pressures can be positive (migration from a region) or negative (new introductions), but are likely to be accompanied by significant economic and environmental consequences. Recent studies indicate the range of invasive weeds such as kudzu and insects such as mountain pine beetle have already expanded to more northern regions as temperatures have risen. To reduce these consequences, a better understanding of the link between CO2/climate and pest biology is needed in the context of existing and new strategies for pest management. This paper provides an overview of the probable biological links and the vulnerabilities of existing pest management (especially chemical control) and provides a preliminary synthesis of research needs that could potentially improve the ability to monitor, mitigate, and manage pest impacts.

  5. Shipborne LiDAR system for coastal change monitoring

    Science.gov (United States)

    Kim, chang hwan; Park, chang hong; Kim, hyun wook; hyuck Kim, won; Lee, myoung hoon; Park, hyeon yeong

    2016-04-01

    Coastal areas, used as human utilization areas like leisure space, medical care, ports and power plants, etc., are regions that are continuously changing and interconnected with oceans and land and the sea level has risen by about 8cm (1.9mm / yr) due to global warming from 1964 year to 2006 year in Korea. Coastal erosion due to sea-level rise has caused the problem of marine ecosystems and loss of tourism resources, etc. Regular monitoring of coastal erosion is essential at key locations with such volatility. But the survey method of land mobile LiDAR (light detection and ranging) system has much time consuming and many restrictions. For effective monitoring beach erosion, KIOST (Korea Institute of Ocean Science & Technology) has constructed a shipborne mobile LiDAR system. The shipborne mobile LiDAR system comprised a land mobile LiDAR (RIEGL LMS-420i), an INS (inertial navigation system, MAGUS Inertial+), a RTKGPS (LEICA GS15 GS25), and a fixed platform. The shipborne mobile LiDAR system is much more effective than a land mobile LiDAR system in the measuring of fore shore areas without shadow zone. Because the vessel with the shipborne mobile LiDAR system is continuously moved along the shoreline, it is possible to efficiently survey a large area in a relatively short time. Effective monitoring of the changes using the constructed shipborne mobile LiDAR system for seriously eroded coastal areas will be able to contribute to coastal erosion management and response.

  6. The comparison of calcium ion release and pH changes from modified MTA and bioceramics in regeneration

    Science.gov (United States)

    Irawan, R. M.; Margono, A.; Djauhari, N.

    2017-08-01

    The surface reactions of bioactive materials release and change dissolutions triggering intracellular and extracellular responses. Calcium ion release can promote alkalinizing activity, which is needed in tissue regeneration. To analyze calcium ion release and pH changes in modified MTA and bioceramics as bioactive materials. Thirty samples, measuring 3 mm in diameter and 3 mm in height, were prepared, with 15 consisting of modified MTA and 15 consisting of bioceramics. Both materials were immersed in deionized water for an hour, then measured and transferred into fresh solutions and soaked for 48 hours or 168 hours. The measurements were conducted using an atom absorption spectrophotometer and pHmeter. Mann Whitney’s post hoc statistic test showed a significant difference among all the 1-hour, 48-hour, and 168-hour measurement groups, with a value of p ≤ 0.05. Bioceramics released more calcium ions and raised pH levels higher than modified MTA for each of the three soak-time groups. Bioceramics released more calcium ion and had higher pH level compared to modified MTA which contributed to the tissue regeneration.

  7. Using a personal watercraft for monitoring bathymetric changes at storm scale

    NARCIS (Netherlands)

    Van Son, S.T.J.; Lindenbergh, R.C.; De Schipper, M.A. .; De Vries, S.; Duijnmayer, K.

    2009-01-01

    Monitoring and understanding coastal processes is important for the Netherlands since the most densely populated areas are situated directly behind the coastal defense. Traditionally, bathymetric changes are monitored at annual intervals, although nowadays it is understood that most dramatic changes

  8. Development of a poultice for electrochemical desalination of porous building materials: desalination effect and pH changes

    DEFF Research Database (Denmark)

    Rörig-Dalgaard, I.

    2013-01-01

    vaults two different techniques are applied: poultices or establishment of climate chambers. Both techniques can result in ion transport away from the valuable surfaces with murals, but satisfying desalination has not been obtained according to conservators from the Danish National Museums mural...... experiment with a traditional poultice significant pH changes and an absence of satisfying high desalination effect was measured. The new idea in the present paper was to introduce a calculated amount of buffer components corresponding to the productions during the electrode processes to a poultice (a solid......) to minimize the adverse effects and to optimize on the effects. The results showed good ability to retain neutral pH values in the substrate which is of major importance when the method should be applied on existing structures. Also the desalination process continued until a very low and harmless salt content...

  9. Effect of pantoprazole in patients with chronic laryngitis and pharyngitis related to gastroesophageal reflux disease: clinical, proximal, and distal pH monitoring results.

    Science.gov (United States)

    Karoui, S; Bibani, N; Sahtout, S; Zouiten, L; Kallel, L; Matri, S; Serghini, M; Ben Mustapha, N; Boubaker, J; Besbes, G; Filali, A

    2010-05-01

    Few studies had evaluated the results of proton pump inhibitors on distal and proximal pH recording using a dual-channel probe. The aim of this study was to determine the clinical and pH-metric effect of treatment with pantoprazole 80 mg for 8 weeks in patients with ear, nose, and throat (ENT) manifestations of gastroesophageal reflux disease associated with pathological proximal acid exposure. We conducted a prospective open study. Patients included had to have chronic pharyngitis or laryngitis, and a pathological gastroesophagopharyngeal reflux. All patients received treatment with pantoprazole 80 mg daily for 8 weeks. One week after the end treatment, patients had a second ENT examination and a 24-hour pH monitoring using dual-channel probe. We included 33 patients (11 men, 22 women). A pathological distal acid reflux was found in 30 patients (91%). After treatment, the improvement of ENT symptoms was found in 51.5% of patients. Normalization of 24-hour proximal esophageal pH monitoring was observed in 22 patients (66%). After treatment, the overall distal acid exposure, the number of distal reflux events, and the number of reflux during more than 5 minutes were significantly decreased (respectively: 19.4% vs 7.2% [P laryngitis.

  10. Land change monitoring, assessment, and projection (LCMAP) revolutionizes land cover and land change research

    Science.gov (United States)

    Young, Steven

    2017-05-02

    When nature and humanity change Earth’s landscapes - through flood or fire, public policy, natural resources management, or economic development - the results are often dramatic and lasting.Wildfires can reshape ecosystems. Hurricanes with names like Sandy or Katrina will howl for days while altering the landscape for years. One growing season in the evolution of drought-resistant genetics can transform semiarid landscapes into farm fields.In the past, valuable land cover maps created for understanding the effects of those events - whether changes in wildlife habitat, water-quality impacts, or the role land use and land cover play in affecting weather and climate - came out at best every 5 to 7 years. Those high quality, high resolution maps were good, but users always craved more: even higher quality data, additional land cover and land change variables, more detailed legends, and most importantly, more frequent land change information.Now a bold new initiative called Land Change Monitoring, Assessment, and Projection (LCMAP) promises to fulfill that demand.Developed at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center in Sioux Falls, South Dakota, LCMAP provides definitive, timely information on how, why, and where the planet is changing. LCMAP’s continuous monitoring process can detect changes as they happen every day that Landsat satellites acquire clear observations. The result will be to place near real-time information in the hands of land and resource managers who need to understand the effects these changes have on landscapes.

  11. Changes in coral reef communities across a natural gradient in seawater pH.

    Science.gov (United States)

    Barkley, Hannah C; Cohen, Anne L; Golbuu, Yimnang; Starczak, Victoria R; DeCarlo, Thomas M; Shamberger, Kathryn E F

    2015-06-01

    Ocean acidification threatens the survival of coral reef ecosystems worldwide. The negative effects of ocean acidification observed in many laboratory experiments have been seen in studies of naturally low-pH reefs, with little evidence to date for adaptation. Recently, we reported initial data suggesting that low-pH coral communities of the Palau Rock Islands appear healthy despite the extreme conditions in which they live. Here, we build on that observation with a comprehensive statistical analysis of benthic communities across Palau's natural acidification gradient. Our analysis revealed a shift in coral community composition but no impact of acidification on coral richness, coralline algae abundance, macroalgae cover, coral calcification, or skeletal density. However, coral bioerosion increased 11-fold as pH decreased from the barrier reefs to the Rock Island bays. Indeed, a comparison of the naturally low-pH coral reef systems studied so far revealed increased bioerosion to be the only consistent feature among them, as responses varied across other indices of ecosystem health. Our results imply that whereas community responses may vary, escalation of coral reef bioerosion and acceleration of a shift from net accreting to net eroding reef structures will likely be a global signature of ocean acidification.

  12. Fast Beam Current Change Monitor for the LHC

    CERN Document Server

    Kral, Jan

    Stringent demands on the LHC safety and protection systems require improved methods of detecting fast beam losses. The Fast Beam Current Transformer (FBCT) is a measurement instrument, providing information about bunch-to-bunch intensity of the accelerated beam. This thesis describes the development of a new protection system based on the FBCT signal measurements. This system, the Fast Beam Current Change Monitor (FBCCM), measures the FBCT signal in a narrow frequency band and computes time derivation of the beam signal magnitude. This derivation is proportional to the beam losses. When the losses exceed a certain level, the FBCCM requests a beam dump in order to protect the LHC. The LHC protection will be ensured by four FBCCMs which will be installed into the LHC in July 2014. Six FBCCMs have been already constructed and their characteristics were measured with satisfactory results. The FBCCMs were tested by a laboratory simulation of the real LHC environment.

  13. Environmental monitoring in peat bog areas by change detection methods

    Science.gov (United States)

    Michel, Ulrich; Mildes, Wiebke

    2016-10-01

    Remote sensing image analysis systems and geographic information systems (GIS) show great promise for the integration of a wide variety of spatial information supporting tasks such as urban and regional planning, natural resource management, agricultural studies and topographic or thematic mapping. Current and future remote sensing programs are based on a variety of sensors that will provide timely and repetitive multisensor earth observation on a global scale. GIS offer efficient tools for handling, manipulating, analyzing and presenting spatial data that are required for sensible decision making in various areas. The Environmental Monitoring project may serve as a convincing example of the operational use of integrated GIS/remote sensing technologies. The overall goal of the project is to assess the capabilities of satellite remote sensing for the analysis of land use changes, especially in moor areas. These areas are recognized as areas crucial to the mission of the Department of Environment and, therefore, to be placed under an extended level of protection. It is of critical importance, however, to have accurate and current information about the ecological and economic state of these sensitive areas. In selected pasture and moor areas, methods for multisensor data fusion have being developed and tested. The results of this testing show which techniques are useful for pasture and moor monitoring at an operational level. A hierarchical method is used for extracting bog land classes with respect to the environmental protection goals. A highly accurate classification of the following classes was accomplished: deciduous- and mixed forest, coniferous forest, water, very wet areas, meadowland/farmland with vegetation, meadowland/farmland with partly vegetation, meadowland/ farmland without vegetation, peat quarrying with maximum of 50% vegetation, de- and regeneration stages. In addition, a change detection analysis is performed in comparison with the existing

  14. Roughness and pH changes of enamel surface induced by soft drinks in vitro-applications of stylus profilometry, focus variation 3D scanning microscopy and micro pH sensor.

    Science.gov (United States)

    Fujii, Mie; Kitasako, Yuichi; Sadr, Alireza; Tagami, Junji

    2011-01-01

    This study aimed to evaluate enamel surface roughness (Ra) and pH before and after erosion by soft drinks. Enamel was exposed to a soft drink (cola, orange juice or green tea) for 1, 5 or 60 min; Ra was measured using contact-stylus surface profilometry (SSP) and non-contact focus variation 3D microscope (FVM). Surface pH was measured using a micro pH sensor. Data were analyzed at significance level of alpha=0.05. There was a significant correlation in Ra between SSP and FVM. FVM images showed no changes in the surface morphology after various periods of exposure to green tea. Unlike cola and orange juice, exposure to green tea did not significantly affect Ra or pH. A significant correlation was observed between surface pH and Ra change after exposure to the drinks. Optical surface analysis and micro pH sensor may be useful tools for non-damaging, quantitative assessment of soft drinks erosion on enamel.

  15. Evaluation of calcium ion release and change in pH on combining calcium hydroxide with different vehicles

    Directory of Open Access Journals (Sweden)

    Charu Grover

    2014-01-01

    Full Text Available Introduction: Intracanal medicaments have traditionally been used in endodontics to disinfect root canals between appointments. Calcium hydroxide is widely used as an intracanal medicament for disinfection and to promote periapical healing. It is stable for long periods, harmless to the body, and bactericidal in a limited area. The efficacy of calcium hydroxide as a disinfectant is dependent on the availability of the hydroxyl ions in the solution that depends on the vehicle in which the calcium hydroxide is carried. In general, three types of vehicles are used: Aqueous, viscous or oily. Some in vitro studies have shown that the type of vehicle has a direct relationship with the concentration and the velocity of ionic liberation as well as with the antibacterial action when the paste is carried into a contaminated area. Aim of the Study: To evaluate the calcium ion release and measure the change in pH of the environment that occurred when calcium hydroxide was combined with different vehicles (distilled water, propylene glycol, calcium hydroxide containing gutta-percha points and chitosan over different time periods. Materials and Methods: Forty single rooted mandibular first premolar teeth were decoronated for this study. Working length was established and the root canals were enlarged and irrigation accomplished with 2 ml of NaOCl solution after every file. The teeth were then randomly divided into four groups. The canals were then packed with different preparations of calcium hydroxide using the following vehicles-distilled water, propylene glycol, gutta-percha points and chitosan. Calcium ion release in different groups was analyzed using an ultraviolet spectrophotometer at 220 nm. The change in pH of was determined using a pH meter. Results were statistically evaluated using one-way ANOVA test. Result: For calcium ion release, Group 2 showed cumulative drug release of 81.97% at the end of 15 days, whereas Group 1, 3 and 4 showed a release

  16. Persistent Robotic Tasks: Monitoring and Sweeping in Changing Environments

    CERN Document Server

    Smith, Stephen L; Rus, Daniela

    2011-01-01

    We present controllers that enable mobile robots to persistently monitor or sweep a changing environment. The changing environment is modeled as a field which grows in locations that are not within range of a robot, and decreases in locations that are within range of a robot. We assume that the robots travel on given closed paths. The speed of each robot along its path is controlled to prevent the field from growing unbounded at any location. We consider the space of speed controllers that can be parametrized by a finite set of basis functions. For a single robot, we develop a linear program that is guaranteed to compute a speed controller in this space to keep the field bounded, if such a controller exists. Another linear program is then derived whose solution is the speed controller that minimizes the maximum field value over the environment. We extend our linear program formulation to develop a multi-robot controller that keeps the field bounded. The multi-robot controller has the unique feature that it do...

  17. Global Monitoring of Martian Surface Albedo Changes from Orbital Observations

    Science.gov (United States)

    Geissler, P.; Enga, M.; Mukherjee, P.

    2013-12-01

    Martian surface changes were first observed from orbit during the Mariner 9 and Viking Orbiter missions. They were found to be caused by eolian processes, produced by deposition of dust during regional and global dust storms and subsequent darkening of the surface through erosion and transportation of dust and sand. The albedo changes accumulated in the 20 years between Viking and Mars Global Surveyor were sufficient to alter the global circulation of winds and the climate of Mars according to model calculations (Fenton et al., Nature 2007), but little was known about the timing or frequency of the changes. Since 1999, we have had the benefit of continuous monitoring by a series of orbiting spacecraft that continues today with Mars Reconnaissance Orbiter, Mars Odyssey, and Mars Express. Daily synoptic observations enable us to determine whether the surface albedo changes are gradual or episodic in nature and to record the seasons that the changes take place. High resolution images of surface morphology and atmospheric phenomena help identify the physical mechanisms responsible for the changes. From these data, we hope to learn the combinations of atmospheric conditions and sediment properties that produce surface changes on Mars and possibly predict when they will take place in the future. Martian surface changes are particularly conspicuous in low albedo terrain, where even a thin layer of bright dust brightens the surface drastically. Equatorial dark areas are repeatedly coated and recoated by dust, which is later shed from the surface by a variety of mechanisms. An example is Syrtis Major, suddenly buried in bright dust by the global dust storm of 2001. Persistent easterly winds blew much of the dust cover away over the course of the next Martian year, but episodic changes continue today, particularly during southern summer when regional dust storms are rife. Another such region is Solis Planum, south of the Valles Marineris, where changes take place

  18. How minimum detectable displacement in a GNSS Monitoring Network change?

    Science.gov (United States)

    Hilmi Erkoç, Muharrem; Doǧan, Uǧur; Aydın, Cüneyt

    2016-04-01

    The minimum detectable displacement in a geodetic monitoring network shows the displacement magnitude which may be just discriminated with known error probabilities. This displacement, which is originally deduced from sensitivity analysis, depends on network design, observation accuracy, datum of the network, direction of the displacement and power of the statistical test used for detecting the displacements. One may investigate how different scenarios on network design and observation accuracies influence the minimum detectable displacements for the specified datum, a-priorly forecasted directions and assumed power of the test and decide which scenario is the best or most optimum. It is sometimes difficult to forecast directions of the displacements. In that case, the minimum detectable displacements in a geodetic monitoring network are derived on the eigen-directions associated with the maximum eigen-values of the network stations. This study investigates how minimum detectable displacements in a GNSS monitoring network change depending on the accuracies of the network stations. For this, CORS-TR network in Turkey with 15 stations (a station fixed) is used. The data with 4h, 6h, 12 h and 24 h observing session duration in three sequential days of 2011, 2012 and 2013 were analyzed with Bernese 5.2 GNSS software. The repeatabilities of the daily solutions belonging to each year were analyzed carefully to scale the Bernese cofactor matrices properly. The root mean square (RMS) values for daily repeatability with respect to the combined 3-day solution are computed (the RMS values are generally less than 2 mm in the horizontal directions (north and east) and < 5 mm in the vertical direction for 24 h observing session duration). With the obtained cofactor matrices for these observing sessions, the minimum detectable displacements along the (maximum) eigen directions are compared each other. According to these comparisons, more session duration less minimum detectable

  19. Monitoring Polar Environmental Change Using FORMOSAT-2 Satellite

    Science.gov (United States)

    Huang, C.; Liu, C.; Chang, L.; Wang, S.; Yan, K.; Wu, F.; Wu, A.

    2007-12-01

    Polar ice loss to the sea currently account for virtually all of the sea-level rise that is not attributable to ocean warming. Huge section of the Ayles Ice Shelf broke off into the Arctic Ocean. Permafrost soil is losing its permanence across the Northern Hemisphere, altering ecosystems and damaging roads and buildings across Alaska, Canada, and Russia. Global warming change the polar environment significantly, especially in recent year. The National Space Organization (NSPO) of Taiwan successfully launched FORMOSAT-2 on 20 May 2004. The orbit is designed to be high-altitude,. Sun-synchronous, and daily-revisit. With high agility in attitude control, FORMOSAT-2 can cover the polar areas up to +/- 90 deg latitude. More than 72 Area of interests in Alaska, Canada, Greenland area and Ice land have imaged periodically in 2006 and 2007. The images have 2m resolution in panchromatic band and 8m in multispectral bands, with size of about 24 x 100 km or large. The ability of FORMOSAT-2 daily revisit has been extended to monitor the change of topography for the glacier and ice shelf daily, weekly and monthly. By using the FORMOSAT-2 stereo pair, we can determine the elevation profile (DEM) across the glacier surface. In this paper, we will present the mapping and topography of Greenland glaciers and ice land including Kangerdlugssuaq Glacier, Greenland, Belcher Glacier, Canada and Ayles ice island. We will demonstrate the DEM extract ability from FORMOSAT-2 polar stereo images( up to 82 deg latitude), and compared with the DEM of the popular SRTM, ASTER which can be acquired to 79 deg latitude. It is expected that FORMOSAT-2 polar images will be continuously collected for years and contribute to the research of global environmental change.

  20. REACTION OF APPLE-TREE VARIETIES AND STOCKS ON CHANGE OF pH OF SOIL

    OpenAIRE

    Doroshenko T. N.; Buzoverov A. V.; Ryazanova L. G.; Zakharchuk N. V.

    2015-01-01

    The researches are devoted to the determination of physiological parameters of grafted apple-trees joining with the level of their resistance to the change of soil рН. The experiments were carried out in the conditions of lysimetric experience with the soils use characterizing by different value of рН. The scheme of experience included the following variants of soil medium reaction: neutral (рН 7,3), typical for black soils of plain part of the region (control); weak-acid (рН 6,2) existing in...

  1. Monitoring lichens diversity and climatic change in Sierra Nevada (Spain

    Directory of Open Access Journals (Sweden)

    Fernández Calzado, M.ª R.

    2013-12-01

    Full Text Available Lichens are common organisms in high mountain zones, where they play an important role in ecosystem balance. In recent years, the increasing interest in understanding more about their interactions with abiotic factors has prompted several investigations, some of which have proved their value as bioindicators of climatic conditions. In this context, focusing on climatic change effects on high mountain vascular plants and supported by the Global Observation Research Initiative in Alpine Environments project (GLORIA, we have monitored for the first time the lichens biodiversity in Sierra Nevada with the intention of studying the alterations caused by the process of climatic change. The aim of this paper is to explain the monitoring experience developed on the massif and contribute to the first results from the biodiversity and statistical analysis of the sampling data.Los líquenes son organismos comunes en las zonas de alta montaña donde juegan un importante papel en el equilibrio de los ecosistemas. En los últimos años, el creciente interés por entender más acerca de sus interacciones con los factores abióticos ha motivado diversas investigaciones, algunas de las cuales han demostrado su valor como bioindicadores de las condiciones climáticas. En este contexto, centrándonos en los efectos del cambio climático en plantas vasculares de alta montaña y respaldados por el proyecto “Iniciativa para la investigación y el seguimiento global de los ambientes alpinos (GLORIA”, se ha monitorizado por primera vez la diversidad de líquenes en Sierra Nevada con la intención de estudiar las posibles alteraciones que esta pueda sufrir causadas por el proceso de cambio climático. El objetivo de este artículo es el de dar a conocer la experiencia de seguimiento en el macizo y aportar los primeros resultados procedentes del análisis, tanto de la biodiversidad como estadístico, de los datos de muestreo.

  2. CHANGE DETECTION BASED ON PERSISTENT SCATTERER INTERFEROMETRY – A NEW METHOD OF MONITORING BUILDING CHANGES

    Directory of Open Access Journals (Sweden)

    C. H. Yang

    2016-06-01

    Full Text Available Persistent Scatterer Interferometry (PSI is a technique to detect a network of extracted persistent scatterer (PS points which feature temporal phase stability and strong radar signal throughout time-series of SAR images. The small surface deformations on such PS points are estimated. PSI particularly works well in monitoring human settlements because regular substructures of man-made objects give rise to large number of PS points. If such structures and/or substructures substantially alter or even vanish due to big change like construction, their PS points are discarded without additional explorations during standard PSI procedure. Such rejected points are called big change (BC points. On the other hand, incoherent change detection (ICD relies on local comparison of multi-temporal images (e.g. image difference, image ratio to highlight scene modifications of larger size rather than detail level. However, image noise inevitably degrades ICD accuracy. We propose a change detection approach based on PSI to synergize benefits of PSI and ICD. PS points are extracted by PSI procedure. A local change index is introduced to quantify probability of a big change for each point. We propose an automatic thresholding method adopting change index to extract BC points along with a clue of the period they emerge. In the end, PS ad BC points are integrated into a change detection image. Our method is tested at a site located around north of Berlin main station where steady, demolished, and erected building substructures are successfully detected. The results are consistent with ground truth derived from time-series of aerial images provided by Google Earth. In addition, we apply our technique for traffic infrastructure, business district, and sports playground monitoring.

  3. Change Detection Based on Persistent Scatterer Interferometry - a New Method of Monitoring Building Changes

    Science.gov (United States)

    Yang, C. H.; Kenduiywo, B. K.; Soergel, U.

    2016-06-01

    Persistent Scatterer Interferometry (PSI) is a technique to detect a network of extracted persistent scatterer (PS) points which feature temporal phase stability and strong radar signal throughout time-series of SAR images. The small surface deformations on such PS points are estimated. PSI particularly works well in monitoring human settlements because regular substructures of man-made objects give rise to large number of PS points. If such structures and/or substructures substantially alter or even vanish due to big change like construction, their PS points are discarded without additional explorations during standard PSI procedure. Such rejected points are called big change (BC) points. On the other hand, incoherent change detection (ICD) relies on local comparison of multi-temporal images (e.g. image difference, image ratio) to highlight scene modifications of larger size rather than detail level. However, image noise inevitably degrades ICD accuracy. We propose a change detection approach based on PSI to synergize benefits of PSI and ICD. PS points are extracted by PSI procedure. A local change index is introduced to quantify probability of a big change for each point. We propose an automatic thresholding method adopting change index to extract BC points along with a clue of the period they emerge. In the end, PS ad BC points are integrated into a change detection image. Our method is tested at a site located around north of Berlin main station where steady, demolished, and erected building substructures are successfully detected. The results are consistent with ground truth derived from time-series of aerial images provided by Google Earth. In addition, we apply our technique for traffic infrastructure, business district, and sports playground monitoring.

  4. Hybrid hard- and soft-modeling of spectrophotometric data for monitoring of ciprofloxacin and its main photodegradation products at different pH values

    Science.gov (United States)

    Razuc, Mariela; Garrido, Mariano; Caro, Yamile S.; Teglia, Carla M.; Goicoechea, Héctor C.; Fernández Band, Beatriz S.

    2013-04-01

    A simple and fast on line spectrophotometric method combined with a hybrid hard-soft modeling multivariate curve resolution (HS-MCR) was proposed for the monitoring of photodegradation reaction of ciprofloxacin under UV radiation. The studied conditions attempt to emulate the effect of sunlight on these antibiotics that could be eventually present in the environment. The continuous flow system made it possible to study the ciprofloxacin degradation at different pH values almost at real time, avoiding errors that could arise from typical batch monitoring of the reaction. On the base of a concentration profiles obtained by previous pure soft-modeling approach, reaction pathways have been proposed for the parent compound and its photoproducts at different pH values. These kinetic models were used as a constraint in the HS-MCR analysis. The kinetic profiles and the corresponding pure response profile (UV-Vis spectra) of ciprofloxacin and its main degradation products were recovered after the application of HS-MCR analysis to the spectra recorded throughout the reaction. The observed behavior showed a good agreement with the photodegradation studies reported in the bibliography. Accordingly, the photodegradation reaction was studied by high performance liquid chromatography coupled with UV-Vis diode array detector (HPLC-DAD). The spectra recorded during the chromatographic analysis present a good correlation with the ones recovered by UV-Vis/HS-MCR method.

  5. Monitoring Period and Amplitude Changes in Classical Cepheids

    Science.gov (United States)

    Erickson, Mary; Engle, Scott G.; Mark Wells (Penn State University)

    2017-01-01

    Cepheid Variable Stars, which are located on the Instability Strip of the Hertzsprung-Russel Diagram, can be used as “standard candle” distance markers (Fiorentino 2007). This came about after the discovery of the Period-Luminosity Relationship (the Leavitt Law), and they have since become a cornerstone of the Cosmic Distance Scale and are helping to further refine the Hubble Constant. Cepheids will cross the Instability Strip, either in a “redward” (cooler) or “blueward” (hotter) direction depending on the stage in which the Cepheid is evolving (Neilson 2012). While Cepheids were originally believed to have regular periods, many are now known to have varying periods, dating back to Eddington (1919). Therefore, Cepheids must be closely monitored in order to deduce where these period variations are coming from - either from inside the star itself or from some outside source. Determining period changes in Cepheids can reveal important information (e.g. evolutionary states, potential companions, etc.).Photometric data were taken for two Cepheids from two different sources and analyzed. The Cepheids in question are AA Gem and BB Gem, both located in the Gemini constellation. Data for these two stars were taken from the All Sky Automated Survey (ASAS) and from the Robotically Controlled Telescope (RCT) at Kitt Peak National Observatory, on which Villanova has guaranteed access. ASAS observes automatically each clear night, and has done so for several years, making it an excellent source for obtaining Cepheid data. The RCT telescope also operates automatically, observing from a preset target list, and achieves a much higher precision than ASAS can. Multi-aperture photometry was performed on the AA Gem and BB Gem RCT images, in Astroimagej. The data were then separated into different seasons, and Fourier fits were applied to the light curves in Kephem (written by Andrej Prša and collaborators). These results were then analyzed via the Hertzsprung Method to

  6. The effect of alginates on deoxycholic-acid-induced changes in oesophageal mucosal biology at pH 4.

    Science.gov (United States)

    Dettmar, Peter W; Strugala, Vicki; Tselepis, Chris; Jankowski, Janusz A

    2007-01-01

    Long-standing gastro-oesophageal reflux disease (GORD) can give rise to Barrett's oesophagus (BM), a metaplastic condition and precursor to oesophageal adenocarcinoma (AC). Oesophageal cancer was once rare but is now the 5th biggest cancer killer in the U.K. Reflux of bile acids into the oesophagus is implicated in the progression to BM as bile acids at pH 4 have been shown to induce c-myc expression, an oncogene upregulated in BM and AC. In the present study we investigated the role of the biopolymer alginate on bile acid induced molecular changes in oesophageal cell lines. OE21, OE33 and TE-7 oesophageal cell lines were exposed to 100 microM deoxycholic acid at pH 4 in the presence or absence of alginates. Levels of c-myc, E-cadherin, beta-catenin and Tcf signalling were determined by Real-Time PCR, Western blotting, immunofluoresence and reporter assays. All alginates tested were able to prevent the induction of c-myc by acidified deoxycholic acid in vitro. The upstream effects of acidified deoxycholic acid on E-cadherin, beta-catenin and Tcf signalling were also suppressed by alginate. Therefore, we have demonstrated that reflux of bile acids into the oesophagus initiates a potentially damaging molecular cascade of events using an in vitro model and that a biopolymer, alginate, can protect against these effects.

  7. Metabolic changes associated with tumor metastasis, part 1: tumor pH, glycolysis and the pentose phosphate pathway.

    Science.gov (United States)

    Payen, Valéry L; Porporato, Paolo E; Baselet, Bjorn; Sonveaux, Pierre

    2016-04-01

    Metabolic adaptations are intimately associated with changes in cell behavior. Cancers are characterized by a high metabolic plasticity resulting from mutations and the selection of metabolic phenotypes conferring growth and invasive advantages. While metabolic plasticity allows cancer cells to cope with various microenvironmental situations that can be encountered in a primary tumor, there is increasing evidence that metabolism is also a major driver of cancer metastasis. Rather than a general switch promoting metastasis as a whole, a succession of metabolic adaptations is more likely needed to promote different steps of the metastatic process. This review addresses the contribution of pH, glycolysis and the pentose phosphate pathway, and a companion paper summarizes current knowledge regarding the contribution of mitochondria, lipids and amino acid metabolism. Extracellular acidification, intracellular alkalinization, the glycolytic enzyme phosphoglucose isomerase acting as an autocrine cytokine, lactate and the pentose phosphate pathway are emerging as important factors controlling cancer metastasis.

  8. [Comment on "Meeting Ph.D. Graduates' needs in a changing global environment"] Challenges to fostering interdisciplinary graduate education

    Science.gov (United States)

    Kock, Beaudry

    C. Susan Weiler's article ("Meeting Ph.D. graduates' needs in a changing global environment," Eos, 55(13), 149, 151) calling for more care and attention to interdisciplinary graduate education illuminated an important and neglected issue. Weiler makes the excellent point that for society to manage complex natural systems effectively, it is imperative that we establish stronger connections between science and public policy. However, as a nation, the United States lacks the institutional research culture to foster this. Nor are we training sufficient numbers of professionals with the skills to make these connections; and when the small number of truly interdisciplinary scientists emerge annually into the workforce, there are few positions that fit them.I echo Weiler's call for increased interdisciplinary collaboration, and the necessary training to support this increase. However, there are some fundamental obstacles her article does not explore.

  9. A framework for habitat monitoring and climate change modelling

    NARCIS (Netherlands)

    Villoslada, Miguel; Bunce, Robert G.H.; Sepp, Kalev; Jongman, Rob H.G.; Metzger, Marc J.; Kull, Tiiu; Raet, Janar; Kuusemets, Valdo; Kull, Ain; Leito, Aivar

    2017-01-01

    Environmental stratifications provide the framework for efficient surveillance and monitoring of biodiversity and ecological resources, as well as modelling exercises. An obstacle for agricultural landscape monitoring in Estonia has been the lack of a framework for the objective selection of

  10. VA Health Care: Processes to Evaluate, Implement, and Monitor Organizational Structure Changes Needed

    Science.gov (United States)

    2016-09-01

    VA HEALTH CARE Processes to Evaluate, Implement, and Monitor Organizational Structure Changes Needed Report to...Monitor Organizational Structure Changes Needed What GAO Found Recent internal and external reviews of Veterans Health Administration (VHA...operations have identified deficiencies in its organizational structure and recommended changes that would require significant restructuring to address

  11. Variação diurna e sazonal do pH e composição mineral da seiva do xilema em tomateiro Seasonal and diurnal changes on pH and mineral composition of tomato xylem sap

    Directory of Open Access Journals (Sweden)

    Maria Neudes S. Oliveira

    2003-03-01

    Full Text Available Variações diárias e sazonais do pH e composição mineral da seiva do xilema foram medidas em plantas de tomateiro com 40 dias, cultivadas em solução nutritiva e em casa de vegetação, visando avaliar os fatores que regulam sua variação. No primeiro experimento, a seiva foi coletada, sempre às 9:00 horas, em alguns meses do ano, em plantas da mesma idade. No segundo, a coleta da seiva ocorreu ao longo do dia, sempre na mesma planta. No terceiro, a seiva foi coletada em dois locais na planta, a 5 cm acima do colo e na base do pecíolo da 5ª folha. Na seiva, avaliaram-se o pH e as concentrações de Ca+2, K+, Mg+2, NH4+, NO3-, PO4-3 e SO4-. O pH variou de 5,3 a 6,4 no período experimental. pH acima de 6,0 ocorreu nos meses com maior temperatura média ambiente e o menor valor, 5,4, nos meses com menor temperatura ambiente. Potássio foi o cátion e nitrato o ânion encontrados em maior concentração na seiva.Considerando a variação diurna, uma maior concentração de nitrato, proporção cátions/ânions e pH ocorreram na seiva coletada à tarde. Considerando a variação sazonal, a maior concentração de nitrato e a proporção cátions/ânions ocorreram na seiva coletada nos meses com menor temperatura média e menores valores de pH. O pH da seiva exsudada do caule a 5 cm acima do colo foi menos ácido (pH 6,13 quando comparado ao pH da seiva exsudada no pecíolo da 5ª folha (pH 5,64. Os resultados sugerem que os fatores que regulam o pH da seiva influenciam diferentemente nas variações diurna e sazonal do pH.Mineral composition and pH seasonal and diurnal changes of xylem sap were measured in tomato plants, 40 days old, cultivated in nutritive solution under green house conditions in order to evaluate the factors that can regulate it. On a first experiment, the sap was obtained from different plants, same age, always at 9:0 AM, during selected months. On a second experiment, the sap was obtained trough the day, at different

  12. CHANGES OF INTERLEUKIN-6 AND RELATED FACTORS AS WELL AS GASTRIC INTRAMUCOSAL Ph DURING COLORECTAL AND ORTHOPAEDIC SURGICAL PROCEDURES

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective To investigate the changes of perioperative serum levels of interleukin-6 ( IL-6), C-reactive protein (CRP), and cortisol, as well as gastric intramucosal pH (pHi) and plasma lactate, aiming to compare systemic changes and tissue perfusion during colorectal and orthopaedic surgical procedures. Methods Twenty patients were randomly assigned to two groups, 10 cases of operation on vertebral canal, 10 cases of colorectal radical operation. Venous blood was drawn at 1 day before operation, 2, 4, and 6 hours following skin incision, and 1 day after operation, in order to measure serum IL-6, CRP, and cortisol, pHi and plasma lactate were also measured at the same time points. Results Serum concentrations of IL-6 and cortisol increased gradually following operation, reaching the peak value at 6 hours from the beginning of operation. CRP was not detectable until the first day after operation. Peak concentration of IL-6 had positive relationship with CRP. These variables changed more significantly in colorectal group than that in orthopaedic group (P < 0. 05). pHi decreased gradually, reaching the lowest level at 4 hours from the beginning of operation, and to more extent in colorectal group than that in orthopaedic group ( P < 0. 05 ).Conclusion IL-6 may reflect tissue damage more sensitively than CRP. Colorectal surgery might induce systemic disorder to more extent, in terms of immuno-endocrinal aspect as well as tissue perfusion, reflected with pHi.

  13. Scalable Distributed Change Detection from Astronomy Data Streams using Local, Asynchronous Eigen Monitoring Algorithms

    Data.gov (United States)

    National Aeronautics and Space Administration — This paper considers the problem of change detection using local distributed eigen monitoring algorithms for next generation of astronomy petascale data pipelines...

  14. Design of a nanocarrier with regulated drug release ability utilizing a reversible conformational transition of a peptide, responsive to slight changes in pH.

    Science.gov (United States)

    Murai, Kazuki; Higuchi, Masahiro; Kinoshita, Takatoshi; Nagata, Kenji; Kato, Katsuya

    2013-07-21

    We investigated the drug releasing behavior of a novel nanocarrier system, utilizing a peptide to act as a nanogate to the mesopore, on a mesoporous silica nanoparticle. The surface peptide on mesoporous silica displayed pH-dependant mesopore cap-uncap switching behavior, enabled by the reversible β-sheet-to-random coil conformational transition resulting from slight pH changes between 8.0 and 6.0. The peptide adopted a β-sheet structure under weakly basic conditions (pH 8.0) and a random coil conformation under weakly acidic conditions (pH 6.0). We demonstrated the pH-dependant regulation of the material's drug release property by the reversible conformational transition of the surface peptide. Under basic pH conditions, the drug release from the nanocarrier was significantly inhibited. However, under acidic pH conditions, the drug in the mesopore was gradually released.

  15. Effect of pH Changes on Antioxidant Capacity and the Content of Betalain Pigments During the Heating of a Solution of Red Beet Betalains

    Directory of Open Access Journals (Sweden)

    Mikołajczyk-Bator Katarzyna

    2017-06-01

    Full Text Available Red beets and their products are mainly consumed after processing. In this study, the effect of pH on changes in antioxidant capacity (AC and the content of betalain pigments were analysed during the heating of a betalain preparation solution. With pH ranging from 4 to 9 during the heat-treatment, the content of red pigments decreased depending on the pH level of the sample. The losses of red pigments in the investigated betalain preparation solution increased along with rising pH levels of the heated solution. The greatest losses were recorded at pH of 9.0. An opposite correlation was observed for yellow pigments. The content of yellow pigments in the heated betalain preparation solution was increasing along with increasing pH. The most pronounced increase in the content of yellow pigments was found at pH of 6.5 and 7.0. At the same time, the heated betalain preparation solution was shown to exhibit a higher antioxidant capacity at pH of 6.0 (14.9 μmol Trolox/mL than at pH of 4.0 (12.6 μmol Trolox/mL. It was observed that the increase in the antioxidant capacity in heated betalain preparation solutions with pH in the 6.0–6.5 range occurred as a result of increased concentrations of neobetanin, assessed by HPLC, within the pH range from 5.0 to 6.5.

  16. Kinetics of an acid-base catalyzed reaction (aspartame degradation) as affected by polyol-induced changes in buffer pH and pK values.

    Science.gov (United States)

    Chuy, S; Bell, L N

    2009-01-01

    The kinetics of an acid-base catalyzed reaction, aspartame degradation, were examined as affected by the changes in pH and pK(a) values caused by adding polyols (sucrose, glycerol) to phosphate buffer. Sucrose-containing phosphate buffer solutions had a lower pH than that of phosphate buffer alone, which contributed, in part, to reduced aspartame reactivity. A kinetic model was introduced for aspartame degradation that encompassed pH and buffer salt concentrations, both of which change with a shift in the apparent pK(a) value. Aspartame degradation rate constants in sucrose-containing solutions were successfully predicted using this model when corrections (that is, lower pH, lower apparent pK(a) value, buffer dilution from the polyol) were applied. The change in buffer properties (pH, pK(a)) from adding sucrose to phosphate buffer does impact food chemical stability. These effects can be successfully incorporated into predictive kinetic models. Therefore, pH and pK(a) changes from adding polyols to buffer should be considered during food product development.

  17. 基于USB接口的在线pH值监测系统%Design of Online pH Monitoring System Based on USB Interface

    Institute of Scientific and Technical Information of China (English)

    张坤; 薛文玲; 李志林; 王振朝

    2013-01-01

    In order to meet the requirements of real-time and the data reproducibility,an online pH monitoring system based on USB interface was developed.The C8051F340 is the system control core.The pH value and the redox potential of solution were detected by glass electrode and Platinum ORP electrode,respectively.The temperature compensation of pH measurement was realized by the temperature sensor DS18B20.The data communication between the PC and the USB controller embedded C8051F340 based on the development tools of the USBXpress.The experimental data show that the system has good real-time,stability and reproducibility.%为了满足实时性和数据重现性的要求,开发了基于USB接口的在线pH值监测系统.系统以C8051 F340单片机为主控芯片,采用玻璃电极检测溶液的pH值,铂金ORP电极检测氧化还原电位,利用温度传感器DS18B20采集溶液温度,通过软件计算实现对pH值的温度补偿.以C8051F340内嵌的USB控制器,结合USBXpress开发工具实现与PC机的数据通信,实现对pH值的在线监测.实验数据表明:系统具有良好的实时性、重现性和稳定性.

  18. 24-hour esophageal pH-monitoring in children suspected of gastroesophageal reflux disease: Analysis of intraesophageal pH monitoring values recorded in distal and proximal channel at diagnosis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To assess values of 24-h esophageal pH-monitoring parameters with dual-channel probe (distal and proximal channel) in children suspected of gastroesophageal reflux disease (GERD).METHODS: 264 children suspected of gastroesophageal reflux (GER) were enrolled in a study (mean age χ = 20.78 ± 17.23 mo). The outcomes of this study,immunoallerrgological tests and positive result of oral food challenge test with a potentially noxious nutrient,enabled to qualify children into particular study groups.RESULTS: 32 (12.1%) infants (group 1) had physiological GER diagnosed. Pathological acid GER was confirmed in 138 (52.3%) children. Primary GER was diagnosed in 76 (28.8%) children (group 2) and GER secondary to allergy to cow milk protein and/or other food (CMA/FA) in 62 (23.5%) children (group 3). 32(12.1%) of them had CMA/FA (group 4-reference group),and in remaining 62 (23.5%) children neither GER nor CMA/FA was confirmed (group 5). Mean values of pH monitoring parameters measured in distal and proximal channel were analyzed in individual groups. This analysis showed statistically significant differentiation of mean values in the case of: number of episodes of acid GER,episodes of acid GER lasting > 5 min, duration of the longest episode of acid GER in both channels, acid GER index total and supine in proximal channel. Statistically significant differences of mean values among examined groups, especially between group 2 and 3 in the case of total acid GER index (only distal channel) were confirmed.CONCLUSION: 24-h esophageal pH monitoring confirmed pathological acid GER in 52.3% of children with typical and atypical symptoms of GERD. The similar pH-monitoring values obtained in group 2 and 3 confirm the necessity of implementation of differential diagnosis for primary vs secondary cause of GER.

  19. Coral calcification in a changing World and the interactive dynamics of pH and DIC upregulation

    Science.gov (United States)

    McCulloch, Malcolm T.; D'Olivo, Juan Pablo; Falter, James; Holcomb, Michael; Trotter, Julie A.

    2017-05-01

    Coral calcification is dependent on the mutualistic partnership between endosymbiotic zooxanthellae and the coral host. Here, using newly developed geochemical proxies (δ11B and B/Ca), we show that Porites corals from natural reef environments exhibit a close (r2 ~0.9) antithetic relationship between dissolved inorganic carbon (DIC) and pH of the corals' calcifying fluid (cf). The highest DICcf (~ × 3.2 seawater) is found during summer, consistent with thermal/light enhancement of metabolically (zooxanthellae) derived carbon, while the highest pHcf (~8.5) occurs in winter during periods of low DICcf (~ × 2 seawater). These opposing changes in DICcf and pHcf are shown to maintain oversaturated but stable levels of carbonate saturation (Ωcf ~ × 5 seawater), the key parameter controlling coral calcification. These findings are in marked contrast to artificial experiments and show that pHcf upregulation occurs largely independent of changes in seawater carbonate chemistry, and hence ocean acidification, but is highly vulnerable to thermally induced stress from global warming.

  20. Integrating population and genetic monitoring to understand changes in the abundance of a threatened seabird

    Science.gov (United States)

    Catalina Vásquez-Carrillo; R. William Henry; Laird Henkel; M. Zachariah. Peery

    2013-01-01

    Population monitoring programs for threatened species are rarely designed to disentangle the effects of movements from changes in birth and death rates on estimated trends in abundance. Here, we illustrate how population and genetic monitoring can be integrated to understand the cause of large changes in the abundance of a threatened species of seabird, the Marbled...

  1. Future monitoring and research needs for forest ecosystems in a changing environment: an introduction

    OpenAIRE

    2009-01-01

    In order to identify future monitoring and research needs, a COST Strategic workshop on the role of "Forest ecosystems in a changing environment" assembled nearly 180 scientists from 30 countries in Istanbul on 11-13 March 2008. The workshop specifically tackled the fields of climate change and forests, ozone, atmospheric deposition and critical loads, biodiversity, as well as quality assurance in forest monitoring.

  2. Behavior Change Techniques Implemented in Electronic Lifestyle Activity Monitors: A Systematic Content Analysis

    Science.gov (United States)

    Lewis, Zakkoyya H; Mayrsohn, Brian G; Rowland, Jennifer L

    2014-01-01

    Background Electronic activity monitors (such as those manufactured by Fitbit, Jawbone, and Nike) improve on standard pedometers by providing automated feedback and interactive behavior change tools via mobile device or personal computer. These monitors are commercially popular and show promise for use in public health interventions. However, little is known about the content of their feedback applications and how individual monitors may differ from one another. Objective The purpose of this study was to describe the behavior change techniques implemented in commercially available electronic activity monitors. Methods Electronic activity monitors (N=13) were systematically identified and tested by 3 trained coders for at least 1 week each. All monitors measured lifestyle physical activity and provided feedback via an app (computer or mobile). Coding was based on a hierarchical list of 93 behavior change techniques. Further coding of potentially effective techniques and adherence to theory-based recommendations were based on findings from meta-analyses and meta-regressions in the research literature. Results All monitors provided tools for self-monitoring, feedback, and environmental change by definition. The next most prevalent techniques (13 out of 13 monitors) were goal-setting and emphasizing discrepancy between current and goal behavior. Review of behavioral goals, social support, social comparison, prompts/cues, rewards, and a focus on past success were found in more than half of the systems. The monitors included a range of 5-10 of 14 total techniques identified from the research literature as potentially effective. Most of the monitors included goal-setting, self-monitoring, and feedback content that closely matched recommendations from social cognitive theory. Conclusions Electronic activity monitors contain a wide range of behavior change techniques typically used in clinical behavioral interventions. Thus, the monitors may represent a medium by which

  3. Monitoring of the proton electrochemical gradient in reconstituted vesicles: quantitative measurements of both transmembrane potential and intravesicular pH by ratiometric fluorescent probes.

    Science.gov (United States)

    Holoubek, Ales; Vecer, Jaroslav; Sigler, Karel

    2007-03-01

    Proteoliposomes carrying reconstituted yeast plasma membrane H(+)-ATPase in their lipid membrane or plasma membrane vesicles are model systems convenient for studying basic electrochemical processes involved in formation of the proton electrochemical gradient (Deltamicro(H) (+)) across the microbial or plant cell membrane. Deltapsi- and pH-sensitive fluorescent probes were used to monitor the gradients formed between inner and outer volume of the reconstituted vesicles. The Deltapsi-sensitive fluorescent ratiometric probe oxonol VI is suitable for quantitative measurements of inside-positive Deltapsi generated by the reconstituted H(+)-ATPase. Its Deltapsi response can be calibrated by the K(+)/valinomycin method and ratiometric mode of fluorescence measurements reduces undesirable artefacts. In situ pH-sensitive fluorescent probe pyranine was used for quantitative measurements of pH inside the proteoliposomes. Calibration of pH-sensitive fluorescence response of pyranine entrapped inside proteoliposomes was performed with several ionophores combined in order to deplete the gradients passively formed across the membrane. Presented model system offers a suitable tool for simultaneous monitoring of both components of the proton electrochemical gradient, Deltapsi and DeltapH. This approach should help in further understanding how their formation is interconnected on biomembranes and even how transport of other ions is combined to it.

  4. Reversible conformational change in herpes simplex virus glycoprotein B with fusion-from-without activity is triggered by mildly acidic pH

    Directory of Open Access Journals (Sweden)

    Nicola Anthony V

    2010-12-01

    Full Text Available Abstract Background The pre-fusion form of the herpes simplex virus (HSV fusion protein gB undergoes pH-triggered conformational change in vitro and during viral entry (Dollery et al., J. Virol. 84:3759-3766, 2010. The antigenic structure of gB from the fusion-from-without (FFWO strain of HSV-1, ANG path, resembles wild type gB that has undergone pH-triggered changes. Together, changes in the antigenic and oligomeric conformation of gB correlate with fusion activity. We tested whether the pre-fusion form of FFWO gB undergoes altered conformational change in response to low pH. Results A pH of 5.5 - 6.0 altered the conformation of Domains I and V of FFWO gB, which together comprise the functional region containing the hydrophobic fusion loops. The ANG path gB oligomer was altered at a similar pH. All changes were reversible. In wild type HSV lacking the UL45 protein, which has been implicated in gB-mediated fusion, gB still underwent pH-triggered changes. ANG path entry was inactivated by pretreatment of virions with low pH. Conclusion The pre-fusion conformation of gB with enhanced fusion activity undergoes alteration in antigenic structure and oligomeric conformation in response to acidic pH. We propose that endosomal pH triggers conformational change in mutant gB with FFWO activity in a manner similar to wild type. Differences apart from this trigger may account for the increased fusion activity of FFWO gB.

  5. Monitor for physical property changes in solid propellants

    Science.gov (United States)

    Black, R. E., Jr.

    1973-01-01

    Specially designed sensor is attached to or imbedded in propellant. When sensor is driven into vibration, it moves with a phase lag directly proportional to internal friction or loss coefficent. Resonance frequency of the system is related to Young's modulus. Modulus or internal friction can be monitored over long period of time.

  6. Dispositivos flexíveis de monitoramento de pH e de deflexão mecânica à base de polianilina Flexible polyaniline devices for strain gauge and pH monitoring applications

    Directory of Open Access Journals (Sweden)

    Silmar A. Travain

    2007-12-01

    Full Text Available Nesse trabalho descrevemos a arquitetura e a operação de filmes finos de polianilina (PAni usados como elemento ativo de sensores flexíveis de pH e de deformação mecânica. Tais dispositivos apresentam grande interesse tecnológico devido aos seus baixos custos de produção e à possibilidade de integração com outros sistemas orgânicos e inorgânicos, incluindo transistores, diodos e baterias. Filmes finos de PAni foram preparados pelo método de polimerização in-situ sobre microeletrodos de Cr/Au previamente depositados sobre substratos de polietilenoteraftalato (PET. As características elétricas do sistema foram investigadas como função do nível de dopagem da PAni. Os dispositivos apresentaram boa resposta elétrica para diferentes soluções ácidas e básicas, bem como para pequenas variações de deformações mecânicas.In this work we describe the design and operation of thin polyaniline (PAni films as active material for strain gauge and pH-monitoring flexible electronic devices. These devices are interesting due to their low cost and possible integration with other organic or inorganic systems, including diodes, transistors and batteries. Thin PAni films were prepared using the in-situ polymerization method on interdigitated chromium-gold microelectrodes previously deposited on poly(ethylene terephthalate - PET substrates. The electrical characteristics of the polymer devices were obtained as a function of the PAni doping level. The devices showed high sensitivity for small strains and acid/base solutions.

  7. Transcriptomic analysis of the dimorphic transition of Ustilago maydis induced in vitro by a change in pH.

    Science.gov (United States)

    Martínez-Soto, Domingo; Ruiz-Herrera, José

    2013-01-01

    Dimorphism is the property of fungi to grow as budding yeasts or mycelium, depending on the environmental conditions. This phenomenon is important as a model of differentiation in eukaryotic organisms, and since a large number of fungal diseases are caused by dimorphic fungi, its study is important for practical reasons. In this work, we examined the transcriptome during the dimorphic transition of the basidiomycota phytopathogenic fungus Ustilago maydis using microarrays, utilizing yeast and mycelium monomorphic mutants as controls. This way, we thereby identified 154 genes of the fungus that are specifically involved in the dimorphic transition induced by a pH change. Of these, 82 genes were up-regulated, and 72 were down-regulated. Differential categorization of these genes revealed that they mostly belonged to the classes of metabolism, cell cycle and DNA processing, transcription and protein fate, transport and cellular communication, stress, cell differentiation and biogenesis of cellular components, while a significant number of them corresponded to unclassified proteins. The data reported in this work are important for our understanding of the molecular bases of dimorphism in U. maydis, and possibly of other fungi.

  8. [Measurement of intracellular pH].

    Science.gov (United States)

    Hanaoka, K; Imai, M; Yoshitomi, K

    1992-09-01

    Since various cellular processes depend on changes in pH, the regulation of intracellular pH (pHi) is important both for the individual cell and for the organism. The mechanisms of the regulation of pHi can be investigated by monitoring pHi. In this report, we discuss the four major techniques available for measuring pHi, which are 1) Distribution of weak acids and bases, 2) pH-sensitive microelectrodes, 3) pH-sensitive dyes, and 4) Nuclear magnetic resonance. Among four techniques, the advantage of the microelectrode approach is that it can monitor membrane potential at the same time and be applied to a single cell. The dye technique is a relative new developing technique, which has lots of advantages. It is easy to use, and is capable of monitoring rapid pHi changes, and being applied to a smaller cell, or a single cell.

  9. In-situ stress measurements and stress change monitoring to monitor overburden caving behaviour and hydraulic fracture pre-conditioning

    Institute of Scientific and Technical Information of China (English)

    Puller Jesse W.; Mills Ken W.; Jeffrey Rob G.; Walker Rick J.

    2016-01-01

    A coal mine in New South Wales is longwall mining 300 m wide panels at a depth of 160–180 m directly below a 16–20 m thick conglomerate strata. As part of a strategy to use hydraulic fracturing to manage potential windblast and periodic caving hazards associated with these conglomerate strata, the in-situ stresses in the conglomerate were measured using ANZI strain cells and the overcoring method of stress relief. Changes in stress associated with abutment loading and placement of hydraulic fractures were also measured using ANZI strain cells installed from the surface and from underground. Overcore stress mea-surements have indicated that the vertical stress is the lowest principal stress so that hydraulic fractures placed ahead of mining form horizontally and so provide effective pre-conditioning to promote caving of the conglomerate strata. Monitoring of stress changes in the overburden strata during longwall retreat was undertaken at two different locations at the mine. The monitoring indicated stress changes were evi-dent 150 m ahead of the longwall face and abutment loading reached a maximum increase of about 7.5 MPa. The stresses ahead of mining change gradually with distance to the approaching longwall and in a direction consistent with the horizontal in-situ stresses. There was no evidence in the stress change monitoring results to indicate significant cyclical forward abutment loading ahead of the face. The for-ward abutment load determined from the stress change monitoring is consistent with the weight of over-burden strata overhanging the goaf indicated by subsidence monitoring.

  10. Acidic pH triggers conformational changes at the NH2-terminal propeptide of the precursor of pulmonary surfactant protein B to form a coiled coil structure.

    Science.gov (United States)

    Bañares-Hidalgo, A; Pérez-Gil, J; Estrada, P

    2014-07-01

    Pulmonary surfactant protein SP-B is synthesized as a larger precursor, proSP-B. We report that a recombinant form of human SP-BN forms a coiled coil structure at acidic pH. The protonation of a residue with pK=4.8±0.06 is the responsible of conformational changes detected by circular dichroism and intrinsic fluorescence emission. Sedimentation velocity analysis showed protein oligomerisation at any pH condition, with an enrichment of the species compatible with a tetramer at acidic pH. Low 2,2,2,-trifluoroethanol concentration promoted β-sheet structures in SP-BN, which bind Thioflavin T, at acidic pH, whereas it promoted coiled coil structures at neutral pH. The amino acid stretch predicted to form β-sheet parallel association in SP-BN overlaps with the sequence predicted by several programs to form coiled coil structure. A synthetic peptide ((60)W-E(85)) designed from the sequence of the amino acid stretch of SP-BN predicted to form coiled coil structure showed random coil conformation at neutral pH but concentration-dependent helical structure at acidic pH. Sedimentation velocity analysis of the peptide indicated monomeric state at neutral pH (s20, w=0.55S; Mr~3kDa) and peptide association (s20, w=1.735S; Mr=~14kDa) at acidic pH, with sedimentation equilibrium fitting to a Monomer-Nmer-Mmer model with N=6 and M=4 (Mr=14692Da). We propose that protein oligomerisation through coiled-coil motifs could then be a general feature in the assembly of functional units in saposin-like proteins in general and in the organization of SP-B in a functional surfactant, in particular. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Changes in the apoplastic pH are involved in regulation of xyloglucan breakdown of azuki bean epicotyls under hypergravity conditions.

    Science.gov (United States)

    Soga, K; Wakabayashi, K; Hoson, T; Kamisaka, S

    2000-04-01

    Hypergravity inhibited elongation growth of azuki bean (Vigna angularis Ohwi et Ohashi) epicotyls by decreasing the mechanical extensibility of cell walls via the increase in the molecular mass of xyloglucans [Soga et al. (1999) Plant Cell Physiol. 40: 581]. Here, we report that the pH value of the apoplastic fluid in epicotyls increased from 5.8 to 6.6 by hypergravity (300 x g) treatment. When the xyloglucan-degrading enzymes extracted from cell walls of the 1 x g control epicotyls were assayed in buffer at pH 6.6 and 5.8, the activity at pH 6.6 was almost half of that at pH 5.8. In addition, when enzymically active cell wall preparations obtained from 1 x g control epicotyls were autolyzed in buffer at pH 5.8 and 6.6 and then xyloglucans were extracted from the autolyzed cell walls, the molecular mass of xyloglucans incubated at pH 5.8 decreased during the autolysis, while that at pH 6.6 did not change. Thus, the xyloglucans were not depolymerized by autolysis at the pH value (6.6) observed in the hypergravity-treated epicotyls. These findings suggest that in azuki bean epicotyls, hypergravity decreases the activities of xyloglucan-degrading enzymes by increasing the pH in the apoplastic fluid, which may be involved in the processes of the increase in the molecular mass of xyloglucans, leading to the decrease in the cell wall extensibility.

  12. Unexpected results from direct measurement, with a torsion microbalance in a closed system, of calcification rates of the coral Agaricia agaricites (Scleractinia:Agariicidae and concomitant changes in seawater pH

    Directory of Open Access Journals (Sweden)

    Ian M. Sandeman

    2014-09-01

    Full Text Available Ocean acidification is impacting the calcification of corals, but the mechanisms of calcification are still unclear. To explore the relationship between calcification and pH, small pieces of coral were suspended from a torsion microbalance in gently stirred, temperature controlled, seawater in a closed chamber. Net calcification rate and pH were continuously monitored while light, temperature or pH could be manipulated. The coral pieces were from the edges of thin plates of Agaricia agaricites and were studied alive and freshly collected. Unexpectedly, when calcification was taking place (n=9, 0.082 mg.hr-1.cm-2, as determined by weight increase, the pH of the surrounding seawater medium changed little (n=10, -0.0047 pH units.hr-1.cm-2. When calcification was not taking place the decrease of seawater pH was an order of magnitude higher, -0.013 pH units.hr-1.cm-2. This is the opposite of what is expected when calcium carbonate (CaCO3 forms. Similarly, fresh skeleton initially showed no change of pH in the seawater medium although the rates of weight gain were high (upto 1.0 mg hr-1.cm-2. After 10 hours, as the rate of deposition decreased following a generalized Michaelis-Menten growth curve, the pH began to decrease dramatically indicating an increase of CO2 in the seawater. These unexpected results can be explained if unstable calcium bicarbonate (Ca(HCO³2 is formed in the organic matrix/carbonic anhydrase surface and slowly transforms later to CaCO3. Pieces of living coral monitored in the chamber for 30 hours gained weight during the day and loss it at night. The loss would be consistent with the transformation of Ca(HCO³2 to CaCO3 with the release of CO2. The mean calcification rate of live coral was greater (n=8, p=0.0027 in high light (120 μmol.s-1.m-2 at 0.098 mg.hr-1.cm-2, compared to 0.063 mg.hr-1.cm-2 in low light (12 μmol.s-1.m-2. However, at the same time the mean rate of pH change was -0.0076 under low light compared to -0

  13. Response of pteropods and foraminifera to changing pCO2 and pH in last 250,000 years

    Science.gov (United States)

    Hart, Malcolm; Wall-Palmer, Deborah; Smart, Christopher

    2010-05-01

    Over the last 250,000 years the diversity and quality of preservation of pteropods (holoplanktic gastropods) has fluctuated in response to glacial/interglacial cycles. This is almost certainly related to the change in oceanic pH as the best preservation is recorded in glacial cycles when pCO2 was at a lower level than during interglacials. Detailed studies of the pteropod assemblages from marine cores taken near Montserrat (Caribbean Sea) have provided a high resolution database with which to make comparisons world-wide. There are peaks of diversity (and good preservation) in Marine Isotope Stages 2 and 6 and these can be found elsewhere in the Gulf of Mexico, in the Indian Ocean and the South China Sea. Using a "pteropod preservation index" it can be seen that this parallels the changing pCO2 and pH and is clearly related. Research on benthic foraminifera living in high CO2, low pH waters near Ischia (Bay of Naples) shows that it is possible to change the foraminifera living in the environment with a change of pH from 8.14 to 7.8 and 7.6. The changes in the diversity and composition of the foraminiferal assemblages parallel changes seen in other benthic faunas (e.g., gastropods, bivalves, echinoderms and calcareous algae). The reductiuon in foraminiferal diversity and the change in the composition of the assemblage is seen to be triggered by a very small change in pH, and something which - if present trends continue - could be seen in the natural world in a few decades.

  14. Design of an integrated flow sensor device with application for monitoring in-situ pH and redox of hydrothermal diffuse flow fluids at mid-ocean ridges

    Science.gov (United States)

    Ding, K.; Seyfried, W. E.; Tan, C.; Jin, B.; Chen, Y.

    2009-05-01

    In-situ measurement of fluid chemistry with chemical sensors at deep sea conditions is always affected by drifting phenomena, which can be especially serious for long-term monitoring studies. Although fundamental changes in sensor design can be used to lessen the effect of this, in-situ calibration is still an unusually effective means to ensure measurement accuracy. With recent development of more reliable valves and pumps applicable for deep sea operation, together with results of laboratory studies showing the viability of solid state chemical sensors, it now possible to achieve in-situ calibration for sensor measurements under challenging chemical and physical conditions. Thus, a new flow device has been designed to facilitate chemical sensor measurements (e.g., pH and redox) in diffuse flow hydrothermal systems at mid-ocean ridges. The integrated calibration and measurement system was developed with a notion of promoting in-situ data acquisition at deep-sea vents for extended periods of time. Accordingly, it enables integration of multiple thermal and chemical sensors, while allowing automated in-situ calibration during deployment. Laboratory tests have successfully demonstrated the effectiveness of this in-situ calibration. For instance in the case of pH measurement with Ir/IrOx pH sensor in NaCl-bearing fluid at 220 bars, the device not only insured reliable measurement in seawater-type fluids, but also revealed effectiveness during measurement of fluids having dissolved CO2 up to 0.52 mol/kg, which is relevant to conditions likely in volcanically active back- arc settings, fluids issuing from cold seeps, as well as monitoring studies in connection with different carbon sequestration scenarios. The sea-going device consists of a sensor cell with limited internal volume of ~ 1 ml for more effectively enhancing interaction between incoming sample fluid and integrated temperature/chemical sensors. The instrument also contains a computer-controlled process

  15. Clinical predictors of abnormal esophageal pH monitoring in preterm infants Preditores clínicos para pHmetria esofágica anormal em prematuros

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Mezzacappa

    2008-09-01

    Full Text Available BACKGROUND: Risk factors for gastroesophageal reflux disease in preterm neonates have not been yet clearly defined. AIM: To identify factors associated with increased esophageal acid exposition in preterm infants during the stay in the neonatal unit. METHODS: A case-control study in preterm infants who had undergone prolonged monitoring of distal esophageal pH, following clinical indication. Eighty-seven preterms with reflux index (percentage of total time of esophageal pHmetry >10% (cases and 87 unpaired preterms were selected with reflux index 10% in preterms were: vomiting, regurgitation, Apnea, female gender. The variables that were associated with a lower frequency of increased reflux index were: volume of enteral intake at the onset of symptoms >147 mL/kg/day, and postnatal corticoid use. CONCLUSIONS: Vomiting, regurgitation, apnea, female gender and acute respiratory distress during the first week of life were variables predictive of increased esophageal acid exposition in preterm infants with birthweight 10%.RACIONAL: Os fatores de risco para a doença pelo refluxo gastroesofágico em recém-nascidos prematuros não foram, até momento, claramente estabelecidos. OBJETIVO: Identificar fatores associados ao aumento da exposição ácida intra-esofágica em prematuros durante o período de internação em unidade neonatal. MÉTODOS: Realizou-se estudo de caso controle com prematuros que realizaram monitorização prolongada do pH esofágico por suspeita clínica de doença do refluxo. Foram selecionados 87 recém-nascidos com valor do índice de refluxo (percentual do tempo total do exame com pH abaixo de 4 >10% (casos e 87 recém-nascidos com índice de refluxo 10% foram: vômitos, regurgitações, apnéia, sexo feminino e insuficiência respiratória na 1ª semana de vida. As variáveis que se associaram a menor freqüência de índice de refluxo 147mL/kg/d e uso de corticóide pós-natal. CONCLUSÕES: Vômitos, regurgitações, apn

  16. PhD students' experiences of thesis supervision in Malaysia: managing relationships in the midst of institutional change

    National Research Council Canada - National Science Library

    Krauss, Steven Eric; Ismail, Ismi Arif

    2010-01-01

    Despite the plethora of studies that have been conducted on PhD supervision, little qualitative investigation has been conducted with a diverse, non-Western sample of doctoral students in an attempt...

  17. Comparison of Mediterranean Pteropod Shell Biometrics and Ultrastructure from Historical (1910 and 1921) and Present Day (2012) Samples Provides Baseline for Monitoring Effects of Global Change

    Science.gov (United States)

    Gattuso, Jean-Pierre; Bijma, Jelle

    2017-01-01

    Anthropogenic carbon perturbation has caused decreases in seawater pH and increases in global temperatures since the start of the 20th century. The subsequent lowering of the saturation state of CaCO3 may make the secretion of skeletons more problematic for marine calcifiers. As organisms that precipitate thin aragonite shells, thecosome pteropods have been identified as being particularly vulnerable to climate change effects. Coupled with their global distribution, this makes them ideal for use as sentinel organisms. Recent studies have highlighted shell dissolution as a potential indicator of ocean acidification; however, this metric is not applicable for monitoring pH changes in supersaturated basins. In this study, the novel approach of high resolution computed tomography (CT) scanning was used to produce quantitative 3-dimensional renderings pteropod shells to assess the potential of using this method to monitor small changes in shell biometrics that may be driven by climate change drivers. An ontogenetic analysis of the shells of Cavolinia inflexa and Styliola subula collected from the Mediterranean was used to identify suitable monitoring metrics. Modern samples were then compared to historical samples of the same species, collected during the Mediterranean leg of the Thor (1910) and Dana (1921) cruises to assess whether any empirical differences could be detected. Shell densities were calculated and scanning electron microscopy was used to compare the aragonite crystal morphology. pH for the collection years was hind-cast using temperature and salinity time series with atmospheric CO2 concentrations from ice core data. Historical samples of S. subula were thicker than S. subula shells of the same size from 2012 and C. inflexa shells collected in 1910 were significantly denser than those from 2012. These results provide a baseline for future work to develop monitoring techniques for climate change in the oceans using the novel approach of high-resolution CT

  18. Perioperative Ruminal pH Changes in Domestic Sheep (Ovis aries) Housed in a Biomedical Research Setting

    OpenAIRE

    Jasmin, Bambi H; Boston, Ray C.; Modesto, Rolf B.; Schaer, Thomas P.

    2011-01-01

    Little information is available on normal ruminal pH values for domestic sheep (Ovis aries) housed in a research setting and fed a complete pelleted ration. Sheep maintained on pelleted diets undergoing surgical procedures often present with postoperative anorexia and rumen atony. To determine the relationship between diet and postoperative rumen acidosis and associated atony, we studied dietary effects on ruminal pH in an ovine surgical model. Sheep undergoing orthopedic surgical procedures ...

  19. Polyurethane-Keratin Membranes: Structural Changes by Isocyanate and pH, and the Repercussion on Cr(VI Removal

    Directory of Open Access Journals (Sweden)

    María D. Manrique-Juárez

    2013-01-01

    Full Text Available Keratin has the capacity to interact with metal ions. In order to take advantage of this potential, a novel membrane with polyurethane and keratin has been developed and studied for removal of Cr(VI from aqueous solution. Physicochemical and morphological properties of these hybrid membranes were studied, varying synthesis parameters such as the type of isocyanate and pH in keratin solution. The effects of using diphenyl-methane-diisocyanate or toluene-diisocyanate and modifying the pH in keratin solutions were evaluated by scanning electron microscopy, Fourier transform infrared spectroscopy, and dynamical mechanical analysis. Results show that pH has a strong influence on morphology and on Cr(VI removal efficiency. When pH in keratin solution is low (2.5, the protein separates from water, and a more closed cell in the membrane is obtained affecting its mechanical properties. The removal efficiency of Cr(VI was also assessed at different pH values of chromium solutions. These results show that when pH of the Cr solution is acidic (at 1.5, the Cr(VI removal percentages increase significantly, reaching up to a 58%. Thus this paper demonstrates the successful combination of synthetic and natural polymers depending on the process parameters to be applied in the critical purpose of remediation of Cr(VI contamination.

  20. Monitoring and Correcting for Response Changes in the CMS Lead-tungstate Electromagnetic Calorimeter

    CERN Document Server

    Ferri, Federico

    2012-01-01

    The CMS Electromagnetic Calorimeter (ECAL) comprises 75848 lead-tungstate scintillating crystals. Changes in the ECAL response, due to crystal radiation damage or changes in photo-detector output, are monitored in real time with a sophisticated system of lasers and LEDs to allow corrections to the energy measurements to be calculated and used. The excellent intrinsic resolution of the CMS ECAL requires the monitoring system itself to be calibrated to a high precision and its stability to be controlled and understood. The components of the CMS ECAL monitoring system, and how it has evolved to include modern solid-state lasers, are described. Several physics channels are exploited to normalize the ECAL response to the changes measured by the monitoring system. These include low energy di-photon resonances, electrons from W and Z decays (using shower energy versus track momentum measurements), and the azimuthal symmetry of low energy deposits in minimum bias events. This talk describes how the monitoring system ...

  1. Change of spider silk tension properties under different pH conditions%不同 pH 值条件下蜘蛛丝收缩与延展性能的变化

    Institute of Scientific and Technical Information of China (English)

    汪波; 于金迪; 郑安妮; 贾甜甜; 周思雨; 陈鑫; 颜亨梅

    2015-01-01

    研究不同pH值条件下,蜘蛛丝拉伸性能的变化。在酸性条件下,设置pH值梯度,比较经丝、纬丝的拉伸性能;使用同样方法,在碱性条件下,比较经丝、纬丝的拉伸性能。将实验数据应用统计学中的单因素方差分析方法分析。结果表明不同pH值对这两类蛛丝的拉伸性能的变化均有显著影响:在酸性条件下,随着pH值的升高,经丝和纬丝收缩度逐渐升高;在碱性条件下,随着pH值的升高,其收缩度逐渐降低。当pH值为7时,经丝和纬丝的收缩度最高,分别为经丝(27.00±0.60)%,纬丝(28.30±0.31)%。%The change of spider silk tension properties under different pH conditions was explored in the laboratory .The result indica-ted that the pH conditions had a significantly affection on tensile properties of radial silk and spiral silk .Under acid condition , the shrinkage degree increased gradually with the increase of pH value , the higher pH condition , the higher shrinkage degree .The shrink-age degree of radial silk reached to (27.00 ±0.60 )%, while spiral silk reached to (28.30 ±0.31 )%, when pH value is was equal to 7.As under alkaline condition , the shrinkago degree of radial silk showed an opposite tendency .The shrinkage degree showed clear negative correlation to the alkaline solution′s pH value .

  2. Seasonal Changes in Endotoxin Exposure and Its Relationship to Exhaled Nitric Oxide and Exhaled Breath Condensate pH Levels in Atopic and Healthy Children.

    Directory of Open Access Journals (Sweden)

    Gwo-Hwa Wan

    Full Text Available Endotoxin, a component of the cell walls of gram-negative bacteria, is a contaminant in organic dusts (house dust and aerosols. In humans, small amounts of endotoxin may cause a local inflammatory response. Exhaled nitric oxide (eNO levels, an inflammation indicator, are associated with the pH values of exhaled breath condensate (EBC. This study evaluated seasonal changes on indoor endotoxin concentrations in homes and the relationships between endotoxin exposure and eNO/EBC pH levels for healthy children and children with allergy-related respiratory diseases. In total, 34 children with allergy-related respiratory diseases and 24 healthy children were enrolled. Indoor air quality measurements and dust sample analysis for endotoxin were conducted once each season inside 58 surveyed homes. The eNO, EBC pH levels, and pulmonary function of the children were also determined. The highest endotoxin concentrations were on kitchen floors of homes of children with allergy-related respiratory diseases and healthy children, and on bedroom floors of homes of asthmatic children and healthy children. Seasonal changes existed in endotoxin concentrations in dust samples from homes of children with allergic rhinitis, with or without asthma, and in EBC pH values among healthy children and those with allergy-related respiratory diseases. Strong relationships existed between endotoxin exposure and EBC pH values in children with allergic rhinitis.

  3. Biological control of beech and hornbeam affects species richness via changes in the organic layer, pH and soil moisture characteristics

    NARCIS (Netherlands)

    Kooijman, A.M.; Cammeraat, E.

    2010-01-01

    1.  Litter quality is an important ecosystem factor, which may affect undergrowth species richness via decomposition and organic layers directly, but also via longer-term changes in soil pH and moisture. The impact of beech trees with low-degradable and hornbeam trees with high-degradable litter on

  4. Monitoring Physiological Changes in Haloarchaeal Cell during Virus Release

    Directory of Open Access Journals (Sweden)

    Julija Svirskaitė

    2016-02-01

    Full Text Available The slow rate of adsorption and non-synchronous release of some archaeal viruses have hindered more thorough analyses of the mechanisms of archaeal virus release. To address this deficit, we utilized four viruses that infect Haloarcula hispanica that represent the four virion morphotypes currently known for halophilic euryarchaeal viruses: (1 icosahedral internal membrane-containing SH1; (2 icosahedral tailed HHTV-1; (3 spindle-shaped His1; and (4 pleomorphic His2. To discern the events occurring as the progeny viruses exit, we monitored culture turbidity, as well as viable cell and progeny virus counts of infected and uninfected cultures. In addition to these traditional metrics, we measured three parameters associated with membrane integrity: the binding of the lipophilic anion phenyldicarbaundecaborane, oxygen consumption, and both intra- and extra-cellular ATP levels.

  5. Monitoring Physiological Changes in Haloarchaeal Cell during Virus Release

    Science.gov (United States)

    Svirskaitė, Julija; Oksanen, Hanna M.; Daugelavičius, Rimantas; Bamford, Dennis H.

    2016-01-01

    The slow rate of adsorption and non-synchronous release of some archaeal viruses have hindered more thorough analyses of the mechanisms of archaeal virus release. To address this deficit, we utilized four viruses that infect Haloarcula hispanica that represent the four virion morphotypes currently known for halophilic euryarchaeal viruses: (1) icosahedral internal membrane-containing SH1; (2) icosahedral tailed HHTV-1; (3) spindle-shaped His1; and (4) pleomorphic His2. To discern the events occurring as the progeny viruses exit, we monitored culture turbidity, as well as viable cell and progeny virus counts of infected and uninfected cultures. In addition to these traditional metrics, we measured three parameters associated with membrane integrity: the binding of the lipophilic anion phenyldicarbaundecaborane, oxygen consumption, and both intra- and extra-cellular ATP levels. PMID:26927156

  6. Air pollution and climate change effects on health of the Ukrainian forests: monitoring and evalution

    Science.gov (United States)

    Igor F. Buksha; Valentina L. Meshkova; Oleg M. Radchenko; Alexander S. Sidorov

    1998-01-01

    Forests in the Ukraine are affected by environmental pollution, intensive forestry practice, and recreational uses. These factors make them sensitive to impacts of climate change. Since 1989 Ukraine has participated in the International Cooperative Program on Assessment and Monitoring of Air Pollution Effects on Forests (ICP-Forests). A network of monitoring plots has...

  7. Transcriptomic analysis reveals how a lack of potassium ions increases Sulfolobus acidocaldarius sensitivity to pH changes.

    Science.gov (United States)

    Buetti-Dinh, Antoine; Dethlefsen, Olga; Friedman, Ran; Dopson, Mark

    2016-08-01

    Extremely acidophilic microorganisms (optimum growth pH of ≤3) maintain a near neutral cytoplasmic pH via several homeostatic mechanisms, including an inside positive membrane potential created by potassium ions. Transcriptomic responses to pH stress in the thermoacidophilic archaeon, Sulfolobus acidocaldarius were investigated by growing cells without added sodium and/or potassium ions at both optimal and sub-optimal pH. Culturing the cells in the absence of added sodium or potassium ions resulted in a reduced growth rate compared to full-salt conditions as well as 43 and 75 significantly different RNA transcript ratios, respectively. Differentially expressed RNA transcripts during growth in the absence of added sodium ions included genes coding for permeases, a sodium/proline transporter and electron transport proteins. In contrast, culturing without added potassium ions resulted in higher RNA transcripts for similar genes as a lack of sodium ions plus genes related to spermidine that has a general role in response to stress and a decarboxylase that potentially consumes protons. The greatest RNA transcript response occurred when S. acidocaldarius cells were grown in the absence of potassium and/or sodium at a sub-optimal pH. These adaptations included those listed above plus osmoregulated glucans and mechanosensitive channels that have previously been shown to respond to osmotic stress. In addition, data analyses revealed two co-expressed IclR family transcriptional regulator genes with a previously unknown role in the S. acidocaldarius pH stress response. Our study provides additional evidence towards the importance of potassium in acidophile growth at acidic pH.

  8. LCMS landscape change monitoring system—results from an information needs assessment

    Science.gov (United States)

    Kevin Megown; Brian Schwind; Don Evans; Mark. Finco

    2015-01-01

    Understanding changes in land use and land cover over space and time provides an important means to evaluate complex interactions between human and biophysical systems, to project future conditions, and to design mitigation and adaptive management strategies. Assessing and monitoring landscape change is evolving into a foundational element of climate change adaptation...

  9. Changes in the fluorescence composition of multiple DOM sources over pH gradients assessed by combining parallel factor analysis and self-organizing maps

    Science.gov (United States)

    Cuss, C. W.; Shi, Y. X.; McConnell, S. M.; Guéguen, C.

    2014-09-01

    Dissolved organic matter is a ubiquitous constituent of natural waters that plays key roles in several important processes. The fluorescence properties of DOM have been linked to its functionality, but these properties may vary with pH. In this study Kohonen's self-organizing maps (SOMs) were applied to excitation-emission matrices (EEMs) of fresh dissolved organic matter (DOM) from three sources: senescent sugar-maple leaves and white spruce needles, and humified white spruce needles, over a pH range of ~4.5 - 12.5. SOMs were applied to raw EEMs, EEMs reduced in dimensionality by pre-processing using parallel factor analysis (PARAFAC), and PARAFAC loading proportions normalized to values at initial pH. Some separation of EEMs into source-based clusters was achieved in the SOM of raw EEMs, but commingling was apparent and evidence of changes over pH gradients was overshadowed. SOMs of PARAFAC component proportions demonstrated clear source-based clustering, and pH-based gradients were visible for DOM from senescent and humified spruce needles. Changes in optical properties were obvious over pH gradients in the SOM of components normalized to starting condition. Component proportions decreased to values as low as 5% of the initial values for microbial humic-like peak M and increased to as high as 278% for a humic-like component. Tyrosine-like fluorescence increased to 112% of initial over increasing pH in humified spruce leachates but decreased to as low as 45% in the other leachates. The combination of PARAFAC and SOM drastically enhanced visualization and interpretability of pH-induced changes in DOM compared to either method alone.

  10. Monitoring of travertine changes resulting from thermal load

    Directory of Open Access Journals (Sweden)

    Zuzana Kompaníková

    2011-06-01

    Full Text Available Travertines, despite of their unique noble appearance change their properties when affected by ageing like any other building and decorative stone. Some of the most noticeable changes are influenced by temperature fluctuations. From this point of view, the main purpose of presented research was to determine the influence of multiple temperature cycles for travertine from Spišské Podhradie and Ludrová in temperature range of 25°C to 60°C corresponding to summer period temperature regimes. The weakening of the rock material by heating was determined by non-destructive techniques before and after thermal load. By ultrasound apparatus was observed by means of ultrasonic velocities change, when higher values of ultrasonic velocities were determined parallel to the bedding while the perpendicular direction had slower velocities. The change of colour was specified by spectrophotometer and no distinct visual colour change was determined with increasing temperature. By non-contact profilometer surface roughness data of samples profiles primarily indicate a decrease of roughness during heating. The coefficient of linear thermal expansion acquired by thermodilatometer varied from 4.6.10-3 to 7.8.10-3 mm.m-1.°C-1 for travertine from Spišské Podhradie and 5.3.10-3 to 7.3.10-3 mm.m-1.°C-1 for travertine from Ludrová. This parameter characterizes the materials response to heating or cooling. The techniques mentioned above are non-destructive and some of them are innovative in laboratory testing.

  11. [Quantitative monitoring the concentration changes of organic acids in fermentation process of Clostridium acetobutylicum using capillary ion electrophoresis].

    Science.gov (United States)

    Cheng, Jiayi; Wang, Tongdan; Kang, Jingwu

    2008-11-01

    A method for monitoring the concentration changes of organic acids in the fermentation process of Clostridium acetobutylicum by capillary ion electrophoresis has been developed. In this study, 4-methoxybenzoic acid was used as the background electrolyte for the indirect ultraviolet detection, and cetyltrimethylammonium chloride (CTAC) was employed as the electroosmotic flow modifier. The sample of fermentation was simply treated by centrifugation and dilution. The optimal conditions for the separation were established as 10 mmol/L of 4-methoxybenzoic acid solution (pH 5. 8) and 0. 15 mmol/L of CTAC solution. The limits of quantification for lactate, acetate and n-butyrate were 1.22, 0.38 and 0.58 mg/L, respectively. The method can be successfully used for the metabolic flux analysis of Clostridium acetobutylicum.

  12. A highly selective chemosensor for colorimetric detection of Hg{sup 2+} and fluorescence detection of pH changes in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Kavitha, Ramasamy; Stalin, Thambusamy, E-mail: drstalin76@gmail.com

    2014-05-01

    A naturally existing and unmodified simple chemosensor, 2-hydroxy-1,4-naphthoquinone (2HNQ), was identified and used for both the colorimetric detection of Hg{sup 2+} and the fluorescent (on-off) detection of pH. The distinct color change and quenching of fluorescence emission was visible to the naked eye. More importantly, the chemosensor was used in combination with β-cyclodextrin (β-CD), which enabled the sensor to be solubilized and stabilized in aqueous solutions. The sensor selectively detected Hg{sup 2+} via the stable 1:1 complexation of the CåO and OH groups with Hg{sup 2+} and reflected pH changes in the range from 6 to 12 via a fluorescence on–off response resulting from the deprotonation of the hydroxyl group in 2HNQ. - Highlights: • The 2-Hydroxy-1,4-Naphthoquinone (2HNQ) chemosensor is capable of both colorimetric detection of Hg{sup 2+} and a fluorescence on-off response to pH. • The distinct color change and quenching of fluorescence emission are detectable with the naked eye. • The on– off fluorescence response in the pH range from 6– to 12 is due to the deprotonation of the hydroxyl group in 2HNQ.

  13. Effects of ethanolamine, pH change, and increased hydrazine levels on deposit-covered alloy 600 and brass corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Barkatt, A.; Labuda, E.; Wilder, D.M. [Catholic Univ. of America, Washington, DC (United States). Dept. of Chemistry; Smialowska, S.; Rebak, R.B. [Ohio State Univ., Columbus, OH (United States). Fontana Corrosion Center; Cherepakhov, G. [Consolidated Edison Co. of New York, Inc., New York, NY (United States); Burns, R.J. [Consolidated Edison Co. of New York, Inc., Buchanan, NY (United States)

    1997-09-01

    Chemical dissolution tests and electrochemical tests were carried out on alloy 600 (UNS N06600) specimens covered with synthetic deposit simulating the tube deposits in the steam generators at Indian Point 2 Station in Buchanan, New York. The tests showed that the introduction of ethanolamine (ETA) and a moderate increase in pH gave rise to lower corrosion rates, but enhancement of hydrazine levels caused them to rise. In the case of brass, both types of tests showed that raising the pH caused the corrosion rates to increase, but the introduction of ETA led to a mild decrease in these rates.

  14. A comprehensive network of measuring stations to monitor climate change

    Energy Technology Data Exchange (ETDEWEB)

    Hari, P. (Dept. of Forest Ecology, Univ. of Helsinki (Finland)); Andreae, M. (Biogeochemistry Dept., Max Planck Institute for Chemistry, Mainz (Germany)); Kabat, P. (Wageningen Univ. and Research Centre (Netherlands)); Kulmala, M. (Dept. of Physics, Univ. of Helsinki (Finland))

    2009-07-01

    The atmospheric CO{sub 2} concentration and temperature have been rather stable at the time scale of millennia, although rather large variations have occurred during longer periods. The extensive use of fossil fuels and destruction of forests have recently increased the atmospheric CO{sub 2} concentrations. Temperature and circulation of water on the globe are reacting to the increase in the atmospheric CO{sub 2} concentration. Mankind urgently needs knowledge on the present climate change and on its effects on living nature. We propose that a network of comprehensive measuring stations should be constructed, utilizing modern technology to provide documentation of the climate change and data for research related to it. To be able to cover spatial and temporal variations, a hierarchy of stations is needed. (orig.)

  15. Monitoring of Changes Signal Acoustic Emission Signals Using Waveguides

    Directory of Open Access Journals (Sweden)

    Jaroslav Začal

    2017-01-01

    Full Text Available This paper is focused on possibilities of acoustic emission (AE signal detection from material surface through waveguide for commonly used piezoelectric sensors. It also considers the experimental study of enhanced detection of occurrence of signal guided through waveguide corpus, its changes and deformities. Aim of this work is verification of several waveguide setup possibilities for maximization of AE signal detection in practice. For this purpose, multiple waveguide setups were manufactured from stainless steel and aluminium alloy. Hsu‑Nielson pen test was utilized for signal actuation. Results demonstrate the differences between measured AE signal with and without employment of waveguide (changes in signal course through different materials and shapes, as well as magnitude of signal dampening and amplification necessary for veritable signal interpretation. Measurements were conducted on agglomerated composite of medium density fibreboard (MDF.

  16. Monitoring the prevalence of postural changes in schoolchildren

    OpenAIRE

    Nichele da Rosa, Bruna; Noll, Matias; Sedrez, Juliana Adami; Furlanetto, Tassia Silveira; Candotti, Claudia Tarrago

    2016-01-01

    [Purpose] The aim of this study was to identify whether postural changes are prevalent with advancing age using a photogrammetric method performing one-year follow-up study. [Subjects and Methods] Thirty-eight schoolchildren were evaluated in 2011 and 2012 in this cohort study. The subjects underwent a postural evaluation, which involved palpation of reference anatomic points, placement of reflexive markers over the anatomic points, image acquisition, and point digitalization using the Digita...

  17. Monitoring variability and changes of the Indonesian Throughflow

    Science.gov (United States)

    Feng, Ming; Wijffels, Susan

    2017-04-01

    The Indonesian Throughflow (ITF) is an important component of the upper cell of the global overturning circulation that provides a low-latitude pathway for warm, fresh waters from the Pacific to enter the Indian Ocean. The IX1 XBT line between the coasts of Australia and Indonesia, initially championed by Gary Meyers, crosses the ITF and has now been in operation for more than 30 years. In this presentation, we review research progresses on the variability and changes of the ITF based on the IX1 XBT data, in memory of Gary's contribution to the Indian Ocean research. The ITF passes across a region that comprises the intersection of two ocean waveguides - those of the equatorial Pacific and equatorial Indian Ocean. The ITF geostrophic transport is stronger during La Niñas and weaker during El Niños. The Indian Ocean wind variability associated with the Indian Ocean Dipole (IOD) in many years offsets the Pacific ENSO influences on the ITF geostrophic transport during the developing and mature phases of El Niño and La Niña, due to the covarying IOD variability with ENSO. The IX1 line reveals the geostrophic ITF decadal and multi-decadal changes: there was a weakening change from the mid-1970s climate regime shift followed by a strengthening trend of about 1 Sv every 10 years over the recent decades. These decadal changes appear mostly due to the ITF responses to decadal variations of the trade winds in the Pacific. Climate models project a weakening trend of the ITF under the global warming, due to the slowdown of the global overturning circulation. The consistent and now multidecadal sampling along IX1 is a precious resource for the climate community and is a testament to the vision and commitment of Gary Meyers to use observations to drive insight into earth's climate variability.

  18. Post-mortem changes in the concentration of lactic acid, phosphates and pH in the muscles of wild rabbits (Oryctolagus cuniculus) according to the perimortal situation.

    Science.gov (United States)

    Mačanga, Ján; Koréneková, Beáta; Nagy, Jozef; Marcinčák, Slavomir; Popelka, Peter; Kožárová, Ivona; Korének, Marián

    2011-08-01

    In this study changes in the concentrations of lactate, phosphates, and pH values of water extracts of muscles of transported and hunted rabbits during ripening were determined. Concentrations of lactate were higher in the muscles of hunted rabbits. The highest differences were obtained 24h after kill/hunt. Concentrations of lactate in the muscles of hunted rabbits were decreasing, while in the muscles of transported rabbits we observed it to increase in the 7th day and then decrease in the 14th day. Higher concentrations of phosphates were found in the muscles of transported wild rabbits. During the ripening process concentrations of phosphates were decreasing in muscles of both groups. Muscles of hunted rabbits had lower pH values during the whole ripening process. Our research showed that concentrations of lactate, phosphates and pH value post-mortem depended on the perimortal situations.

  19. SDS-facilitated in vitro formation of a transmembrane B-type cytochrome is mediated by changes in local pH

    DEFF Research Database (Denmark)

    Weber, M.; Schneider, D.; Prodöhl, A.

    2011-01-01

    dissociation. Surprisingly, absorption spectroscopy reveals that heme binding and cytochrome formation at pH 8.0 are optimal at intermediate SDS concentrations. Stopped-flow kinetics revealed that genuine conformational changes are involved in heme binding at these SDS concentrations. GPS (Global Protein...... potential of SDS lowers the local pH sufficiently to restore efficient heme binding, provided the amount of SDS needed for this does not denature the protein. Accordingly, the higher the pH value above 6-7, the more SDS is needed to improve heme binding, and this competes with the inherent tendency of SDS...... to dissociate cytochrome b(559)'. Our work highlights that, in addition to its denaturing properties, SDS can affect protein functions by lowering the local pH....

  20. Growth and survival in a changing environment: Combined effects of moderate hypoxia and low pH on juvenile bivalve Macoma balthica

    Science.gov (United States)

    Jansson, Anna; Norkko, Joanna; Dupont, Sam; Norkko, Alf

    2015-08-01

    Baltic Sea species live in a complex, variable environment characterized by highly fluctuating hydrology, including large seasonal and diel pH variations. For decades, oxygen deficiency caused by anthropogenic eutrophication has affected the Baltic Sea, and large areas of the seafloor are permanently hypoxic resulting in severely degraded benthic communities. Species living in this system are thus potentially tolerant and adapted to this fluctuating environment, but also vulnerable as illustrated by high mortality of benthic species as a result of hypoxia. In the future, the frequency and extent of regularly co-occurring low oxygen and low pH levels will likely increase with on-going climate change. A key species in the Baltic Sea soft-bottom communities, the bivalve Macoma balthica (L.), experiences such conditions throughout its life-cycle, and therefore serves as a good model organism for studying the combined effects of oxygen and pH conditions. To study the response of M. balthica to multiple changes occurring in the benthic environment, we conducted an experiment to investigate the survival and shell growth of newly settled juveniles simultaneously exposed to two pH levels (7.85 and 7.35) and two oxygen levels (8.5 and 3.0 mg/l) for 29 days in a fully factorial design. Survival was high in all treatments (> 60%), but significantly higher in the two low oxygen treatments (> 70%). Although positive growth was observed in all treatments, pH and oxygen as well as their interaction significantly affected relative growth. The highest growth was observed in the "low O2/high pH" treatment, which was 2.4 times higher than in both treatments with high oxygen. Although the mechanism for these differences remains unknown, hypoxia-induced metabolic depression likely plays a role. Our results highlight the need to know more about the occurrence and performance of benthic species regularly exposed to changing conditions, and of the range and conditions encountered in situ

  1. Changes in the size of the apparent surface area and adsorption energy of the rye roots by low pH and the presence of aluminium ions induced

    Science.gov (United States)

    Szatanik-Kloc, Alicja

    2016-07-01

    The plant reactions on Al-stress include i.a. change of the surface area of the roots, which in the physicochemistry of plants characterizes the transport of water and ions through the root. The object of this study is the specific surface area of the roots of plants which are tolerant to aluminium, such as rye. Plants of rye were grown in a nutrient solution for 14 days at pH 4.5 in the presence of Al3+ ions of concentration 10, 20, and 40 mg dm-3. The control plants were grown continuously at pH 7 or pH 4.5 without Al3+. The apparent surface area and adsorption energy of the plants roots were determined from water vapour adsorption - desorption data. The apparent surface area of roots growing in the aluminium was (with respect to control) statistically significantly lower. There were no statistically significant differences in the apparent surface area of the roots which grew in pH 7, pH 4.5 without Al3+. The average water vapour adsorption energy of the root surface, under stress conditions decreased. In the roots grown in the presence of Al+3, there was a slight decrease in high energy adsorption centres and an increase in the amount of low-energy centres.

  2. Changes in composition and enamel demineralization inhibition activities of gallic acid at different pH values

    NARCIS (Netherlands)

    Zhang, J.; Huang, X.; Huang, S.; Deng, M.; Xie, X.; Liu, M.; Liu, H.; Zhou, X.; Li, J.; ten Cate, J.M.

    2015-01-01

    Background. Gallic acid (GA) has been shown to inhibit demineralization and enhance remineralization of enamel; however, GA solution is highly acidic. This study was to investigate the stability of GA solutions at various pH and to examine the resultant effects on enamel demineralization. Methods. T

  3. PhD Students' Experiences of Thesis Supervision in Malaysia: Managing Relationships in the Midst of Institutional Change

    Science.gov (United States)

    Krauss, Steven Eric; Ismail, Ismi Arif

    2010-01-01

    Despite the plethora of studies that have been conducted on PhD supervision, little qualitative investigation has been conducted with a diverse, non-Western sample of doctoral students in an attempt to understand how the supervisory relationship is experienced. In response, eighteen students from diverse, non-Western backgrounds studying at one…

  4. THE CHANGE OF ARTERIOVENOUS CARBON DIOXIDE AND pH GRADIENTS DURING SEVERE HEMORRHAGIC SHOCK AND RESUSCITATION

    Institute of Scientific and Technical Information of China (English)

    黄宇光; 曾清楷; 罗爱伦

    1998-01-01

    Objective. To investigate clidcally useful markers for determining the severity of hemorrhagic shock and adequacy of resuscitation. Methods. Prospective study was undertaken in 12 dogs, using an established model for hemorrhagic shock. The anesthetized dogs were bled to s mean arterial pressure of 40 mmHg which was maintained for 3 hours. Then each animal was resuscitated with heperinized whole blood followed by intravenous infusion of dobutamine at a rate of 5 μg·kg-1·min-1 for 10 minutes. Arterial and mixed venous blood gases, arterial lactate concentrations and bemndynamic parameters were measured throughout the study. Results. A difference in the PCO2 and pH values between arterial and mixed venous blond was observed. Arterlal-venous PCO2 and pH difference increased signifmantly after sustained shock. The arterioveraxts carbon dioxide and pH gradients recovered more rapidly than arterial lactate levels after successful resuscitation with blond and dobutamine. Conclusion. Arterial blood gases fail to reflect the acld-base status of tissues during hemorrhagic shock,The differences in PCO2 and pH vslues between arterial and mixed venous blood could he used as clinical indicators for assessing the severity of shock and efficacy of resuscitation.

  5. Preparation of Micro-biosensor and Its Application in Monitoring in vivo Change of Dopamine

    Institute of Scientific and Technical Information of China (English)

    QIAO Xian; DING Hong; WANG Zhifang

    2005-01-01

    The self-made high sensitivity and selectivity micro-biosensor was applied to monitor the change of dopamine in cerebral nucleus in rats in vivo. The micro-biosensor was prepared and used to detect dopamine level in vitro and monitor the dynamic change of dopamine in different cerebral nucleus in vivo. The results showed the lowest concentration of dopamine that could be detected by the biosensor was 32.5 nmol/L. Its positive peak was significantly different from that of AA, 5-HTP and E. The biosensor could keep working for monitoring the dopamine concentration in the cerebral tissue for more than 10 h. It was concluded that the microsensor has high sensitivity and selectivity to dopamine and can be used to dynamically monitor the change of dopamine in vivo.

  6. Arterial pressure changes monitoring with a new precordial noninvasive sensor

    Directory of Open Access Journals (Sweden)

    Faita Francesco

    2008-08-01

    Full Text Available Abstract Background Recently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2 amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes. Methods The transcutaneous force sensor was positioned in the precordial region in 146 consecutive patients referred for exercise (n = 99, dipyridamole (n = 41, or pacing stress (n = 6. The curve of S2 peak amplitude variation as a function of heart rate was computed as the increment with respect to the resting value. Results A consistent S2 signal was obtained in all patients. Baseline S2 was 7.2 ± 3.3 mg, increasing to 12.7 ± 7.7 mg at peak stress. S2 percentage increase was + 133 ± 104% in the 99 exercise, + 2 ± 22% in the 41 dipyridamole, and + 31 ± 27% in the 6 pacing patients (p Conclusion S2 recording quantitatively documents systemic pressure changes.

  7. Structural Health Monitoring in Changing Operational Conditions Using Tranmissibility Measurements

    Directory of Open Access Journals (Sweden)

    Christof Devriendt

    2010-01-01

    Full Text Available This article uses frequency domain transmissibility functions for detecting and locating damage in operational conditions. In recent articles numerical and experimental examples were presented and the possibility to use the transmissibility concept for damage detection seemed quite promising. In the work discussed so far, it was assumed that the operational conditions were constant, the structure was excited by a single input in a fixed location. Transmissibility functions, defined as a simple ratio between two measured responses, do depend on the amplitudes or locations of the operational forces. The current techniques fail in the case of changing operational conditions. A suitable operational damage detection method should however be able to detect damage in a very early stage even in the case of changing operational conditions. It will be demonstrated in this paper that, by using only a small frequency band around the resonance frequencies of the structure, the existing methods can still be used in a more robust way. The idea is based on the specific property that the transmissibility functions become independent of the loading condition in the system poles. A numerical and experimental validation will be given.

  8. The effect of changes in gastric pH induced by omeprazole on the absorption and respiratory depression of methadone.

    Science.gov (United States)

    de Castro, J; Aguirre, C; Rodríguez-Sasiaín, J M; Gómez, E; Garrido, M J; Calvo, R

    1996-10-01

    The effect of omeprazole (2 mg kg-1 i.v.) on respiratory depression induced in rats by acute oral methadone administration (5 mg kg-1) was examined and compared with control animals that only received methadone. Quantitative assessments of arterial Pco2,Po2, pH, and respiratory rate were employed as criteria for evaluation. Intragastric pH was measured in each rat immediately before and 2 h after methadone. Plasma concentration of methadone was measured for 3 h. The relationship between drug effect and the systemic bioavailability of methadone, measured as the area under the plasma concentration-time curve (AUC0-180), was also evaluated. The intensity of the methadone-induced respiratory depression was significantly greater in the omeprazole group than in control rats. A significant variation (p Omeprazole caused a significant increase in methadone levels (Cmax = 156 +/- 6.5 ng mL-1 against 51 +/- 5.8 ng mL-1 in control; p omeprazole treatment (18.6 +/- 1.4 micrograms mL-1 min) than in control (6.8 +/- 0.6 microgram mL-1 min). Two hours after treatment with omeprazole, intragastric pH values were significantly elevated (4.7 +/- 0.1 against 2.2 +/- 0.04) and continued increasing, being 6.4 +/- 0.1 at the end of the experiment. Correlation was observed between intragastric pH and the area under the effect- (respiratory depression-) time curve (r = 0.74; p bicarbonate whereas opposite results were obtained with acidic pH2 solution.

  9. ANTS AS BIOLOGICAL INDICATORS FOR MONITORING CHANGES IN ARID ENVIRONMENTS: LESSONS FOR MONITORING PROTECTED AREAS

    Science.gov (United States)

    The responses of ant communities to structural change (removal of an invasive were studied in a replicated experiment in a Chihuahuan Desert grassland. The results from sampling of ant communities by pit-fall trapping were validated by mapping ant colonies on the experimental plo...

  10. ANTS AS BIOLOGICAL INDICATORS FOR MONITORING CHANGES IN ARID ENVIRONMENTS: LESSONS FOR MONITORING PROTECTED AREAS

    Science.gov (United States)

    The responses of ant communities to structural change (removal of an invasive were studied in a replicated experiment in a Chihuahuan Desert grassland. The results from sampling of ant communities by pit-fall trapping were validated by mapping ant colonies on the experimental plo...

  11. Monitoring Changes in Soil Water Content Using Subsurface Displacement

    Science.gov (United States)

    Thrash, C. J.; Miller, S.; Murdoch, L. C.; Germanovich, L. N.; Gates, J. B.; Volkmer, A.; Weinburg, A.

    2013-12-01

    Closing the water balance is important in many research and water resource applications, but it can be difficult to accomplish due to a variety of factors. A new technique that measures vertical displacement of soil in order to estimate the change in mass of water stored in overlying material is being developed. The measurement technique uses an extensometer that functions as a lysimeter, and we refer to the technique as Displacement Extensometry for Lysimetric Terrain Analysis (DELTA). DELTA extensometers are 2-m-long devices deployed by creating a friction fit with intact soil below a cased borehole. The instrument measures small displacements (better than 10 nm resolution) in response to changes of mass in the overlying soil, or other factors. The instrument averages over a region that scales with the depth of installation (the radius of influence is approximately 2x the depth). The spatial averaging of this instrument extends over regions representative of agricultural fields, hydrologic model grid blocks, and small watersheds. Five DELTA extensometers have been deployed at a field site near Clemson, SC at depths of 3, 6, and 9 m within saprolite derived from biotite gneiss. Barometric pressure, precipitation, and soil moisture are being measured along with displacement. Signals from the co-located extensometers are remarkably similar, demonstrating reproducibility of the technique. Rainfall causes soil compression, and at 6 m depth there is approximately 200 nm of compression per 1 mm of rainfall. There is gradual expansion, which ranges from 0.15 to 1.75 μm/day, following rainfall. The gradual unloading of the soil is interpreted as water loss due to evapotranspiration. Superimposed on the signal are diurnal fluctuations of 0.5 to 1 μm, which correlate to changes in barometric pressure. Four DELTA extensometers were recently deployed in hard, clayey sediments at two field locations south of Amarillo, TX. The instruments will compliment current research on

  12. Monitoring of changes in substrate characteristics during mushroom compost production.

    Science.gov (United States)

    Lyons, Gary A; Sharma, H S Shekhar; Kilpatrick, Mairead; Cheung, Linda; Moore, Solveig

    2006-06-28

    Substrates from three mushroom compost facilities in Northern Ireland, employing similar production technologies, were examined to assess the quality of the compost produced. Biochemical investigation highlighted changes in substrates through each step of the production cycle. Thermogravimetric analysis (TGA) provided useful information on fiber fraction content and extent of substrate breakdown. A comparison of productivity, chemical, and thermal data permitted assessment of the degree of bioconversion that had occurred in the decomposition from raw materials to finished substrate for each composter. One of the composters consistently produced substrate of inferior quality compared to the other two, indicating production inefficiencies during composting. Results demonstrated that allied to chemical analyses, TGA is a useful tool, providing valuable information on substrate quality and, in particular, for studying the bioconversion of lignocellulosic materials in mushroom compost.

  13. Exploring the process-structure-function relationship of horseradish peroxidase through investigation of pH- and heat induced conformational changes

    Science.gov (United States)

    Stănciuc, Nicoleta; Aprodu, Iuliana; Ioniță, Elena; Bahrim, Gabriela; Râpeanu, Gabriela

    2015-08-01

    Given the importance of peroxidase as an indicator for the preservation of vegetables by heat treatment, the present study is focused on enzyme behavior under different pH and temperature conditions, in terms of process-structure-function relationships. Thus, the process-structure-function relationship of peroxidase was investigated by combining fluorescence spectroscopy, in silico prediction methods and inactivation kinetic studies. The fluorescence spectra indicated that at optimum pH value, the Trp117 residue is not located in the hydrophobic core of the protein. Significant blue- and red-shifts were obtained at different pH values, whereas the heat-treatment did not cause significant changes in Trp and Tyr environment. The ANS and quenching experiments demonstrated a more flexible conformation at lower pH and respectively at higher temperature. On the other hand molecular dynamics simulations at different temperatures highlighted that the secondary structure appeared better preserved against temperature, whereas the tertiary structure around the heme was more affected. Temperature dependent changes in the hydrogen bonding and ion paring involving amino acids from the heme-binding region (His170 and Asp247) might trigger miss-coordination of the heme iron atom by His170 residue and further enzyme activity loss.

  14. Stakeholder perspectives on triage in wildlife monitoring in a rapidly changing Arctic

    Directory of Open Access Journals (Sweden)

    Helen C Wheeler

    2016-11-01

    Full Text Available Monitoring activities provide a core contribution to wildlife conservation in the Arctic. Effective monitoring which allows changes in population status to be detected early, provides opportunities to mitigate pressures driving declines. Monitoring triage involves decisions about how and where to prioritise activities in species and ecosystem based monitoring. In particular, monitoring triage examines whether to divert resources away from species where there is high likelihood of extinction in the near-future in favour of species where monitoring activities may produce greater conservation benefits. As a place facing both rapid change with a high likelihood of population extinctions, and serious logistic and financial challenges for field data acquisition, the Arctic provides a good context in which to examine attitudes toward triage in monitoring.For effective decision-making to emerge from monitoring, multiple stakeholders must be involved in defining aims and priorities. We conducted semi-structured interviews with stakeholders in arctic wildlife monitoring (either contributing to observation and recording of wildlife, using information from wildlife observation and recording, or using wildlife as a resource to elicit their perspectives on triage in wildlife monitoring in the Arctic.The majority (56% of our 23 participants were predominantly in opposition to triage, 26% were in support of triage and 17% were undecided. Representatives of Indigenous organisations were more likely to be opposed to triage than scientists and those involved in decision-making showed greatest support for triage amongst the scientist participants. Responses to the concept of triage included that: 1 The species-focussed approach associated with triage did not match their more systems-based view (5 participants, 2 Important information is generated through monitoring threatened species which advances understanding of the drivers of change, responses and ecosystem

  15. Landscape Change and Sandy Desertification Monitoring and Assessment

    Directory of Open Access Journals (Sweden)

    Eltahir M. Elhadi

    2009-01-01

    Full Text Available Problem statement: The objective of this study is to develop techniques for assessing and analyzing sand desertification in the northern part of Shaanxi Province, China. Approach: In order to reveal the process of land degradation, especially the latest situation of sandy desertification, a method integrating remote sensing, Geographic Information System (GIS and field survey was employed to build a sandy desertification dataset for analysis. Remote Sensing images included the Landsat Thematic Mapper (TM images in 1987 and Landsat Enhanced Thematic Mapper Plus (ETM+ images in 1999. Eight land-cover classes, including active sand dunes, fixed sand dunes, semi-fixed sand dunes, grass land, farm land, wet land, built up area and unused land and Normalized Difference Vegetation Index (NDVI, were identified. Results: The results showed that the active sand dunes and semi-fixed sand dunes have increased with a change rate of 128.70 and 55.65 km2 year-1, respectively, in the meantime the fixed sand dunes has decreased with a decreasing rate of 182.14 km2 year-1. During the 1987s, the area of sandy desertified land reached 12,006.11 km2 (57.17% of the total sandy area, of which severely desertified, medium desertified and slightly desertified land areas were 4,442.23, 4,253.45 and 3,310.43 km2, respectively. By the year 1999, the area of desertified land was increased to 13,782.30 km2 (65.63% of the total sandy area, of which severely desertified, medium desertified and slightly desertified land areas were 5,169.89, 4,918.15 and 3,694.26 km2, respectively increasing by 1,776.19 km2. Conclusion: Spatial change detection based on active sand dunes showed that the expansion area was much larger than the reversion in the past two decades and that several active sand belts has been formed, suggesting that sandy desertification of northern part of Shaanxi Province, China, will be a long-term task.

  16. MECHANISMS AND MOLECULAR MONITORING OF PHOSPHIN RESISTANCE IN STORE D GRAIN PESTS%储粮害虫PH3抗性机理及分子监测研究进展

    Institute of Scientific and Technical Information of China (English)

    吴芳; 严晓平

    2011-01-01

    Resistance of stored grain pests to phosphine has attracted much attention. Mechanisms of phosphine resistance in stored grain pests has been researched extensively in the past several decades, but inconclu-siveness yet. With the development of molecular biology in recent years, molecular monitoring of stored grain pest resistance of phosphine are more and more concerned. In this paper, advances in mechanisms and molecular monitoring of phosphine resistance in stored grain pests are reviewed.%储粮害虫PH3抗性一直倍受关注.在过去几十年中,人们对储粮害虫PH3抗性产生的生化机理进行了广泛的研究,但尚无定论.近年来,随着分子生物学的发展,储粮害虫PH3抗性分子监测方面的研究也日益受到重视.综述了储粮害虫PH3抗性产生的生化机制及PH3抗性分子监测方面的研究进展.

  17. Design considerations for community-based stream monitoring to detect changes in Pacific salmon habitats

    Directory of Open Access Journals (Sweden)

    Cory R. Lagasse

    2014-12-01

    Full Text Available Communities in the Great Bear Rainforest of British Columbia, Canada are highly dependent on Pacific salmon (Oncorhynchus spp. and the watersheds that support them, yet current monitoring efforts are likely inadequate for detecting changes in stream habitats that may affect salmon populations. The Coastal First Nations Regional Monitoring System is attempting to address these information gaps through a new stream assessment program that collects baseline information and tracks changes in stream habitats. Using the program's monitoring protocol, we assessed the habitat characteristics of eight streams within the Koeye and Namu watersheds, then used a statistical power simulation to determine within-stream sampling requirements for detecting changes in substrate composition that may affect salmon habitat suitability. We also assessed resource constraints and perceived threats to stream habitats via questionnaires to coastal First Nations' stewardship staff. Results suggest that the current recommended sample size of 6 within-stream transects has low statistical power for detecting biologically significant changes in fine sediment. Given limited monitoring resources, we recommend higher transect sampling intensities within productive riffle-pool streams, but an emphasis on monitoring site level characteristics, such as large woody debris and pool volume, in less productive, high gradient cascade-pool streams. Questionnaire results highlight the need for flexibility and local adaptation in monitoring efforts because of differences in resource constraints among First Nations communities. If successfully implemented, the stream assessment program can integrate local knowledge with western science to inform ecosystem-based management of watersheds within the Great Bear Rainforest.

  18. Merging Developmental and Feminist Evaluation to Monitor and Evaluate Transformative Social Change

    Science.gov (United States)

    Haylock, Laura; Miller, Carol

    2016-01-01

    Programs seeking to challenge and change gender and power relationships require a nimble, evolving monitoring, evaluation, and learning (MEL) system that helps make sense of how nonlinear complex social change happens. This article describes efforts by Oxfam Canada to develop such a system for a women's rights and gender equality program. The…

  19. Investigation of Phasic Process of Biogas Yield by Measuring pH, ORP and Electrical Power Changes

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Abdoli

    2016-04-01

    Full Text Available Background & Aims of the Study: Studying the phasic process of the biogas yieldis required to optimize the design and operations; it also helps to lower energy production costs by decreasing the capital investment and operational costs. Here we determine the biogas process by measuring pH, ORP, electrical power and make compatibility to the biogas production trend. Materials and Methods: In this research, one 1150 ml single chamber reactor is used. Biogas production trend was precisely followed by a probable compatibleness with pH, Oxidation Reduction Potential (ORP, electrical Power at a temperature of 37+ 0.5˚C with the substrate of cattle manure. The experiment was followed for 120 days approximately. Results: As a result, the phases of biogas yield could be determined by the measuring of pH, ORP and its compatibility to gas production. In the reactor, hydrolytic, acetogenic and methanogenic phases were occurred in the days 1-7, 8-16 and 17-104, respectively. Also the electrical power at first showed to be produced at high range but by increasing, the production of biogas decreased and then by decreasing the biogas production gradually, it increased slightly. Conclusion: Our results indicated that the phases of biogas production can be separated  completely and by diffracting the phases, the efficiency of biogas production could be increased.

  20. EFFECT OF LUMINAL pH CHANGES ON GUAR GUM-HPMC E15 LV MIXED MATRIX TABLETS FOR MESALAMINE DRUG DELIVERY TO COLON AND STUDY ON IN- VITRO CHARACTERISTICS IN TWO DIFFERENT DISSOLUTION MODELS vs. MARKETED FORMULATION

    Directory of Open Access Journals (Sweden)

    A. Maria John Newton*, L. Prabakaran and K.N. Jayaveera

    2012-07-01

    Full Text Available The study was designed to investigate the impact of colonic pH changes on formulated colon targeted Mesalamine matrix tablets in the treatment of inflammatory bowel disease (IBD. Mesalamine tablets were fabricated with guar gum as Polymer system. The different batches of Mesalamine tablets (GMM1-GMM6 were compressed with increasing proportion of guar gum and HPMC E15 LV. The different buffer conditions were chosen to mimic the pH changes in terminal part of the ileum as well as the colon. A separate two in vitro studies were conducted in all the formulations. The impact of the pH changes on the coated tablets in normal pH condition and reduced pH condition (pH reduced during IBD were compared. In IBD the pH of the colon falls below its normal level. The extent of pH change depends on the severity of the disease. The study was designed to evaluate the in vitro dissolution characteristics of Mesalamine matrix tablets in a variety of simulated fluids (pH range 1.2, 6, 6.8, 7.2, 5. The results indicated that the impact of pH changes on drug release profile was not affected in the diseased and normal pH condition of the colon. The present treatment methods of IBD mostly depend on pH sensitivity polymers or enteric coating technique. These pH sensitive polymers based colonic devices may not serve the patient needs successfully because the influence of colonic pH on pH sensitive polymer based devices plays an important role in triggering the drug release in target site. The lowered pH condition in diseased state could not trigger the drug release in pH sensitive polymer based devices as it was not the threshold pH of the particular coated polymer. In case of enteric coating there may be a possibility of disintegration of the tablet before reaching the colon due to the contractile movement of GI tract and fluctuation in the GI pH. The present matrix tablets were prepared with guar gum, which cannot be affected by the pH changes of the colon, maintained

  1. The effect of antioxidants on quantitative changes of lysine and methionine in linoleic acid emulsions at different pH conditions

    Directory of Open Access Journals (Sweden)

    Marzanna Hęś

    2017-03-01

    Full Text Available Background. Plants are an important source of phenolic compounds. The antioxidant capacities of green tea, thyme and rosemary extracts that contain these compounds have been reported earlier. However, there is a lack of accessible information about their activity against lipid oxidation in emulsions and inhibit the interaction of lipid oxidation products with amino acids. Therefore, the influence of green tea, thyme and rosemary extracts and BHT (butylated hydroxytoluene on quantitative changes in lysine and methionine in linoleic acid emulsions at a pH of isoelectric point and a pH lower than the isoelectric point of amino acids was investigated. Material and methods. Total phenolic contents in plant extracts were determined spectrophotometrically by using Folin-Ciocalteu’s reagent, and individual phenols by using HPLC. The level of oxidation of emulsion was determined using the measurement of peroxides and TBARS (thiobarbituric acid reactive substances. Methionine and lysine in the system were reacted with sodium nitroprusside and trinitrobenzenesulphonic acid respectively, and the absorbance of the complexes was measured. Results. Extract of green tea had the highest total polyphenol content. The system containing antioxidants and amino acid protected linoleic acid more efficiently than by the addition of antioxidants only. Lysine and methionine losses in samples without the addition of antioxidants were lower in their isoelectric points than below these points. Antioxidants decrease the loss of amino acids. The protective properties of antioxidants towards methionine were higher in a pH of isoelectric point whereas towards lysine in pH below this point. Conclusion. Green tea, thyme and rosemary extracts exhibit antioxidant activity in linoleic acid emulsions. Moreover, they can be utilized to inhibit quantitative changes in amino acids in lipid emulsions. However, the antioxidant efficiency of these extracts seems to depend on pH

  2. The effect of antioxidants on quantitative changes of lysine and methionine in linoleic acid emulsions at different pH conditions.

    Science.gov (United States)

    Hęś, Marzanna; Gliszczyńska-Świgło, Anna; Gramza-Michałowska, Anna

    2017-01-01

    Plants are an important source of phenolic compounds. The antioxidant capacities of green tea, thyme and rosemary extracts that contain these compounds have been reported earlier. However, there is a lack of accessible information about their activity against lipid oxidation in emulsions and inhibit the interaction of lipid oxidation products with amino acids. Therefore, the influence of green tea, thyme and rosemary extracts and BHT (butylated hydroxytoluene) on quantitative changes in lysine and methionine in linoleic acid emulsions at a pH of isoelectric point and a pH lower than the isoelectric point of amino acids was investigated. Total phenolic contents in plant extracts were determined spectrophotometrically by using Folin-Ciocalteu's reagent, and individual phenols by using HPLC. The level of oxidation of emulsion was determined using the measurement of peroxides and TBARS (thiobarbituric acid reactive substances). Methionine and lysine in the system were reacted with sodium nitroprusside and trinitrobenzenesulphonic acid respectively, and the absorbance of the complexes was measured. Extract of green tea had the highest total polyphenol content. The system containing antioxidants and amino acid protected linoleic acid more efficiently than by the addition of antioxidants only. Lysine and methionine losses in samples without the addition of antioxidants were lower in their isoelectric points than below these points. Antioxidants decrease the loss of amino acids. The protective properties of antioxidants towards methionine were higher in a pH of isoelectric point whereas towards lysine in pH below this point. Green tea, thyme and rosemary extracts exhibit antioxidant activity in linoleic acid emulsions. Moreover, they can be utilized to inhibit quantitative changes in amino acids in lipid emulsions. However, the antioxidant efficiency of these extracts seems to depend on pH conditions. Further investigations should be carried out to clarify this issue.

  3. The KCNQ5 potassium channel from mouse: a broadly expressed M-current like potassium channel modulated by zinc, pH, and volume changes

    DEFF Research Database (Denmark)

    Jensen, Henrik Sindal; Callø, Kirstine; Jespersen, Thomas

    2005-01-01

    H-dependent potentiation by Zn2+ (EC50 = 21.8 microM at pH 7.4), inhibition by acidification (IC50 = 0.75 microM; pKa = 6.1), and regulation by small changes in cell volume. Furthermore, the channels are activated by the anti-convulsant drug retigabine (EC50 = 2.0 microM) and inhibited by the M-current blockers...

  4. "Ultrasound Monitoring of Temperature Change during Interstitial Laser Thermotherapy of Liver: An In Vitro Study"

    Directory of Open Access Journals (Sweden)

    T. Gorji-Ara

    2007-07-01

    Full Text Available Background/objective: In thermal tissue ablation, it is very important to control the increase in the temperature for having an efficient ablation therapy. We conducted this study to determine the efficacy of measuring pixel shift of ultrasound B-mode images as a function of change in tissue temperature. Materials and Methods: By fixing some microthermocouples in liver tissues, temperature at different points was monitored invasively in vitro during laser-induced thermotherapy. According to our results, optimum power and exposure time were determined for ultrasound temperature monitoring. Simultaneously, noninvasive temperature monitoring was performed with ultrasound B-mode images. These images were saved on computer from 25ºC to 95ºC with 10 ºC steps. The speed of sound changes with each 10°C temperature change that produce virtual shifts in the scatter positions. Using an image processing method, the pixel shift due to 10 °C temperature change was extracted by motion detection. Results: The cubic regression function between the mean pixel shifts on ultrasound B-mode images caused by the change in speed of sound, which in turn was a function of the mean change in temperature, was evaluated. When temperature increased, pixel shift occurs in ultrasound images. The maximum pixel shift was observed between 60 to 70 ºC (temperature changes (ΔT of 35–45 ºC. After 70ºC, the local pixel shift due to change in the speed of sound in liver tissue had an irregular decreasing. Pearson correlation coefficient between invasive and non-invasive measurements for 10°C temperature changes was 0.93 and the non-linear function was suitable for monitoring of temperature. Conclusion: Monitoring of changes in temperature based on pixel shifts observed in ultrasound B-mode images in interstitial laser thermotherapy of liver seems a good modality.

  5. Mildly Acidic pH Triggers an Irreversible Conformational Change in the Fusion Domain of Herpes Simplex Virus 1 Glycoprotein B and Inactivation of Viral Entry.

    Science.gov (United States)

    Weed, Darin J; Pritchard, Suzanne M; Gonzalez, Floricel; Aguilar, Hector C; Nicola, Anthony V

    2017-03-01

    Herpes simplex virus (HSV) entry into a subset of cells requires endocytosis and endosomal low pH. Preexposure of isolated virions to mildly acidic pH of 5 to 6 partially inactivates HSV infectivity in an irreversible manner. Acid inactivation is a hallmark of viruses that enter via low-pH pathways; this occurs by pretriggering conformational changes essential for fusion. The target and mechanism(s) of low-pH inactivation of HSV are unclear. Here, low-pH-treated HSV-1 was defective in fusion activity and yet retained normal levels of attachment to cell surface heparan sulfate and binding to nectin-1 receptor. Low-pH-triggered conformational changes in gB reported to date are reversible, despite irreversible low-pH inactivation. gB conformational changes and their reversibility were measured by antigenic analysis with a panel of monoclonal antibodies and by detecting changes in oligomeric conformation. Three-hour treatment of HSV-1 virions with pH 5 or multiple sequential treatments at pH 5 followed by neutral pH caused an irreversible >2.5 log infectivity reduction. While changes in several gB antigenic sites were reversible, alteration of the H126 epitope was irreversible. gB oligomeric conformational change remained reversible under all conditions tested. Altogether, our results reveal that oligomeric alterations and fusion domain changes represent distinct conformational changes in gB, and the latter correlates with irreversible low-pH inactivation of HSV. We propose that conformational change in the gB fusion domain is important for activation of membrane fusion during viral entry and that in the absence of a host target membrane, this change results in irreversible inactivation of virions.IMPORTANCE HSV-1 is an important pathogen with a high seroprevalence throughout the human population. HSV infects cells via multiple pathways, including a low-pH route into epithelial cells, the primary portal into the host. HSV is inactivated by low-pH preexposure, and gB, a

  6. Using Copernicus earth observation services to monitor climate change impacts and adaptations

    Science.gov (United States)

    Becker, Daniel; Zebisch, Marc; Sonnenschein, Ruth; Schönthaler, Konstanze; von Andrian-Werburg, Stefan

    2016-04-01

    In the last years, earth observation made a big leap towards an operational monitoring of the state of environment. Remote sensing provides for instance information on the dynamics, trends and anomalies of snow and glaciers, vegetation, soil moisture or water temperature. In particular, the European Copernicus initiative offers new opportunities through new satellites with a higher temporal and spatial resolution, operational services for environmental monitoring and an open data access policy. With the Copernicus climate change service and the ESA climate change initiative, specific earth observation programs are in place to address the impacts of climate change. However, such products and services are until now rarely picked up in the field of policy or decision making oriented climate impact or climate risk assessments. In this talk, we will present results of a study, which focus on the question, if and how remote sensing approaches could be integrated into operational monitoring activities of climate impacts and response measures on a national and subnational scale. We assessed all existing and planned Copernicus services regarding their relevance for climate impact monitoring by comparing them against the indication fields from an indicator system for climate impact and response monitoring in Germany, which has lately been developed in the framework of the German national adaptation strategy. For several climate impact or response indicators, an immediate integration of remote sensing data could be identified and been recommended. For these cases, we will show practical examples on the benefit of remote sensing data. For other indication fields, promising approaches were found, which need further development. We argue that remote sensing is a very valuable complement to the existing indicator schemes by contributing with spatial explicit, timely information but not always easy to integrate with classical approaches, which are oriented towards consistent long

  7. In Vitro binding capacity of zeolite A to calcium, phosphorus and magnesium in rumen fluid as influenced by changes in pH

    DEFF Research Database (Denmark)

    Thilsing, Trine; Jørgensen, Rolf Jess; Poulsen, H.D.

    2006-01-01

    An in vitro experiment was designed to mimic the transport of ingested zeolite A in the forestomachs and proximal part of the small intestine so as to evaluate the binding capacity of zeolite A to Ca, P and Mg as influenced by changes in pH. This was done by incubation of rumen fluid solutions...... with and without zeolite, as well as varying the content of Ca and/or P. The pH was lowered by addition of HCl so as to mimic abomasal conditions, followed by subsequent HCO3- addition to mimic small intestinal pH. Rumen fluid samples were taken at strategic time points in the experiment. All samples were...... centrifuged and the supernatant analysed for Ca, P and Mg as indicators of the amount of unbound mineral. The addition of zeolite to rumen fluid solutions reduced the amount of supernatant Ca and Mg at rumen pH, whereas the level of P was not reduced. After adding HCl, a large proportion of the zeolite...

  8. Bioindicators of changes in water quality on coral reefs: review and recommendations for monitoring programmes

    Science.gov (United States)

    Cooper, T. F.; Gilmour, J. P.; Fabricius, K. E.

    2009-09-01

    Effective environmental management requires monitoring programmes that provide specific links between changes in environmental conditions and ecosystem health. This article reviews the suitability of a range of bioindicators for use in monitoring programmes that link changes in water quality to changes in the condition of coral-reef ecosystems. From the literature, 21 candidate bioindicators were identified, whose responses to changes in water quality varied spatially and temporally; responses ranged from rapid (hours) changes within individual corals to long-term (years) changes in community composition. From this list, the most suitable bioindicators were identified by determining whether responses were (i) specific, (ii) monotonic, (iii) variable, (iv) practical and (v) ecologically relevant to management goals. For long-term monitoring programmes that aim to quantify the effects of chronic changes in water quality, 11 bioindicators were selected: symbiont photophysiology, colony brightness, tissue thickness and surface rugosity of massive corals, skeletal elemental and isotopic composition, abundance of macro-bioeroders, micro- and meiobenthic organisms such as foraminifera, coral recruitment, macroalgal cover, taxonomic richness of corals and the maximal depth of coral-reef development. For short-term monitoring programmes, or environmental impact assessments that aim to quantify the effects of acute changes in water quality, a subset of seven of these bioindicators were selected, including partial mortality. Their choice will depend on the specific objectives and the timeframe available for each monitoring programme. An assessment framework is presented to assist in the selection of bioindicators to quantify the effects of changing water quality on coral-reef ecosystems.

  9. A smart DNA tetrahedron that isothermally assembles or dissociates in response to the solution pH value changes.

    Science.gov (United States)

    Liu, Zhiyu; Li, Yingmei; Tian, Cheng; Mao, Chengde

    2013-06-10

    This communication reports a DNA tetrahedron whose self-assembly is triggered by an acidic environment. The key element is the formation/dissociation of a short, cytosine (C)-containing, DNA triplex. As the solution pH value oscillates between 5.0 and 8.0, the DNA triplex will form and dissociate that, in turn, leads to assembly or disassembly of the DNA tetrahedron, which has been demonstrated by native polyacrylamide gel electrophoresis (PAGE). We believe that such environment-responsive behavior will be important for potential applications of DNA nanocages such as on-demand drug release.

  10. Effects of the addition of nanoparticulate calcium carbonate on setting time, dimensional change, compressive strength, solubility and pH of MTA.

    Science.gov (United States)

    Bernardi, A; Bortoluzzi, E A; Felippe, W T; Felippe, M C S; Wan, W S; Teixeira, C S

    2017-01-01

    To evaluate nanoparticulate calcium carbonate (NPCC) using transmission electron microscopy and the effects of NPCC addition to MTA in regard to the setting time, dimensional change, compressive strength, solubility and pH. The experimental groups were G1 (MTA), G2 (MTA with 5% NPCC) and G3 (MTA with 10% NPCC). The tests followed ISO and ADA standards. The specimens in the dimensional change and compressive strength tests were measured immediately after setting, after 24 h and after 30 days. In the solubility test, rings filled with cement were weighed after setting and after 30 days. The pH was measured after 24 h and 30 days. The data were analysed with the ANOVA, Tukey's and Kruskal-Wallis tests (α = 5%). The setting time was reduced (P  G2 > G3). The solubility test revealed a difference amongst the groups when the specimens were hydrated: G2 > G1 > G3 and dehydrated: G3 > G2 > G1. The pH of the groups was similar at 24 h with higher values in each group after 30 days (P MTA accelerated the setting time, decreased compressive strength and, after 30 days, resulted in lower dimensional change (G2), higher solubility and a higher pH. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  11. Estimation of change in populations and communities from monitoring survey data

    Science.gov (United States)

    Sauer, J.R.; Link, W.A.; Nichols, J.D.; Busch, David E.; Trexler, Joel C.

    2003-01-01

    Monitoring surveys provide fundamental information for use in environmental decision making by permitting assessment of both current population (or community) status and change in status, by providing a historical context of the present status, and by documenting response to ongoing management. Conservation of species and communities has historically been based upon monitoring information, and prioritization of species and habitats for conservation action often requires reliable, quantitative results. Although many monitoring programs exist for populations, species, and communities, as well as for biotic and abiotic features of the environment, estimation of population and community change from surveys can sometimes be controversial, and demands on monitoring information have increased greatly in recent years. Information is often required at multiple spatial scales for use in geographic information systems, and information needs exist for description of regional patterns of change in populations, communities, and ecosystems. Often, attempts are made to meet these needs using information collected for other purposes or at inappropriate geographic scales, leading to information that is difficult to analyze and interpret. In this chapter, we address some of the constraints and issues associated with estimating change in wildlife species and species groups from monitoring surveys, and use bird surveys as our primary examples.

  12. Plant Habitat (PH)

    Science.gov (United States)

    Onate, Bryan

    2016-01-01

    The International Space Station (ISS) will soon have a platform for conducting fundamental research of Large Plants. Plant Habitat (PH) is designed to be a fully controllable environment for high-quality plant physiological research. PH will control light quality, level, and timing, temperature, CO2, relative humidity, and irrigation, while scrubbing ethylene. Additional capabilities include leaf temperature and root zone moisture and oxygen sensing. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs. There will be several internal cameras (visible and IR) to monitor and record plant growth and operations.

  13. Metal release from contaminated coastal sediments under changing pH conditions: Implications for metal mobilization in acidified oceans.

    Science.gov (United States)

    Wang, Zaosheng; Wang, Yushao; Zhao, Peihong; Chen, Liuqin; Yan, Changzhou; Yan, Yijun; Chi, Qiaoqiao

    2015-12-30

    To investigate the impacts and processes of CO2-induced acidification on metal mobilization, laboratory-scale experiments were performed, simulating the scenarios where carbon dioxide was injected into sediment-seawater layers inside non-pressurized chambers. Coastal sediments were sampled from two sites with different contamination levels and subjected to pre-determined pH conditions. Sediment samples and overlying water were collected for metal analysis after 10-days. The results indicated that CO2-induced ocean acidification would provoke increased metal mobilization causing adverse side-effects on water quality. The mobility of metals from sediment to the overlying seawater was correlated with the reduction in pH. Results of sequential extractions of sediments illustrated that exchangeable metal forms were the dominant source of mobile metals. Collectively, our data revealed that high metal concentrations in overlying seawater released from contaminated sediments under acidic conditions may strengthen the existing contamination gradients in Maluan Bay and represent a potential risk to ecosystem health in coastal environments.

  14. Genome-Wide Mutation Rate Response to pH Change in the Coral Reef Pathogen Vibrio shilonii AK1

    Directory of Open Access Journals (Sweden)

    Chloe Strauss

    2017-08-01

    Full Text Available Recent application of mutation accumulation techniques combined with whole-genome sequencing (MA/WGS has greatly promoted studies of spontaneous mutation. However, such explorations have rarely been conducted on marine organisms, and it is unclear how marine habitats have influenced genome stability. This report resolves the mutation rate and spectrum of the coral reef pathogen Vibrio shilonii, which causes coral bleaching and endangers the biodiversity maintained by coral reefs. We found that its mutation rate and spectrum are highly similar to those of other studied bacteria from various habitats, despite the saline environment. The mutational properties of this marine bacterium are thus controlled by other general evolutionary forces such as natural selection and genetic drift. We also found that as pH drops, the mutation rate decreases and the mutation spectrum is biased in the direction of generating G/C nucleotides. This implies that evolutionary features of this organism and perhaps other marine microbes might be altered by the increasingly acidic ocean water caused by excess CO2 emission. Nonetheless, further exploration is needed as the pH range tested in this study was rather narrow and many other possible mutation determinants, such as carbonate increase, are associated with ocean acidification.

  15. Relevance of hydro-climatic change projection and monitoring for assessment of water cycle changes in the Arctic.

    Science.gov (United States)

    Bring, Arvid; Destouni, Georgia

    2011-06-01

    Rapid changes to the Arctic hydrological cycle challenge both our process understanding and our ability to find appropriate adaptation strategies. We have investigated the relevance and accuracy development of climate change projections for assessment of water cycle changes in major Arctic drainage basins. Results show relatively good agreement of climate model projections with observed temperature changes, but high model inaccuracy relative to available observation data for precipitation changes. Direct observations further show systematically larger (smaller) runoff than precipitation increases (decreases). This result is partly attributable to uncertainties and systematic bias in precipitation observations, but still indicates that some of the observed increase in Arctic river runoff is due to water storage changes, for example melting permafrost and/or groundwater storage changes, within the drainage basins. Such causes of runoff change affect sea level, in addition to ocean salinity, and inland water resources, ecosystems, and infrastructure. Process-based hydrological modeling and observations, which can resolve changes in evapotranspiration, and groundwater and permafrost storage at and below river basin scales, are needed in order to accurately interpret and translate climate-driven precipitation changes to changes in freshwater cycling and runoff. In contrast to this need, our results show that the density of Arctic runoff monitoring has become increasingly biased and less relevant by decreasing most and being lowest in river basins with the largest expected climatic changes.

  16. Research on Monitoring the Wetland Landcover Change Based on the Moderate Resolution Remote Sensing Image

    Science.gov (United States)

    Zhou, M.; Yuan, X.; Sun, L.

    2015-04-01

    Wetland is important natural resource. The main method to monitor the landcover change in wetland natural reserve is to extract and analyze information from remote sensing image. In this paper, the landcover information is extracted, summarized and analyzed by using multi-temporal HJ and Landsat satellite image in Zhalong natural reserve, Heilongjiang, China. The method can monitor the wetland landcover change accurately in real time and long term. This paper expounds the natural factors and human factors influence on wetland land use type, for scientific and effective support for the development of the rational use of wetlands in Zhalong natural wetland reserve.

  17. Incorporation of 5-hydroxytryptophan into transferrin and its receptor allows assignment of the pH induced changes in intrinsic fluorescence when iron is released.

    Science.gov (United States)

    James, Nicholas G; Byrne, Shaina L; Mason, Anne B

    2009-03-01

    Human serum transferrin (hTF) is a bilobal glycoprotein that transports iron to cells. At neutral pH, diferric hTF binds with nM affinity to the transferrin receptor (TFR) on the cell surface. The complex is taken into the cell where, at the acidic pH of the endosome ( approximately pH 5.6), iron is released. Since iron coordination strongly quenches the intrinsic tryptophan fluorescence of hTF, the increase in the fluorescent signal reports the rate constant(s) of iron release. At pH 5.6, the TFR considerably enhances iron release from the C-lobe (with little effect on iron release from the N-lobe). The recombinant soluble TFR is a dimer with 11 tryptophan residues per monomer. In the hTF/TFR complex these residues could contribute to and compromise the readout ascribed to iron release from hTF. We report that compared to Fe(C) hTF alone, the increase in the fluorescent signal from the preformed complex of Fe(C) hTF and the TFR at pH 5.6 is significantly quenched (75%). To dissect the contributions of hTF and the TFR to the change in fluorescence, 5-hydroxytryptophan was incorporated into each using our mammalian expression system. Selective excitation of the samples at 280 or 315 nm shows that the TFR contributes little or nothing to the increase in fluorescence when ferric iron is released from Fe(C) hTF. Quantum yield determinations of TFR, Fe(C) hTF and the Fe(C) hTF/TFR complex strongly support our interpretation of the kinetic data.

  18. Daytime changes of skin biophysical characteristics: A study of hydration, transepidermal water loss, ph, sebum, elasticity, erythema, and color index on middle eastern skin

    Directory of Open Access Journals (Sweden)

    Alireza Firooz

    2016-01-01

    Full Text Available Background: The exposure of skin to ultraviolet radiation and temperature differs significantly during the day. It is reasonable that biophysical parameters of human skin have periodic daily fluctuation. The objective of this study was to study the fluctuations of various biophysical characteristics of Middle Eastern skin in standardized experimental conditions. Materials and Methods: Seven biophysical parameters of skin including stratum corneum hydration, transepidermal water loss, pH, sebum, elasticity, skin color, and erythema index were measured at three time points (8 a.m., 12 p.m. and 4 p.m. on the forearm of 12 healthy participants (mean age of 28.4 years without any ongoing skin disease using the CK MPA 580 device in standard temperature and humidity conditions. Results: A significant difference was observed between means of skin color index at 8 a.m. (175.42 ± 13.92 and 4 p.m. (164.44 ± 13.72, P = 0.025, between the pH at 8 a.m. (5.72 ± 0.48 and 4 p.m. (5.33 ± 0.55, P = 0.001 and pH at 12 p.m. (5.60 ± 0.48 and 4 p.m. (5.33 ± 0.55, P = 0.001. Other comparisons between the means of these parameters at different time points resulted in nonsignificant P values. Conclusion: There are daytime changes in skin color index and pH. Skin color index might be higher and cutaneous pH more basic in the early morning compared to later of the day.

  19. In vivo imaging of the morphology and changes in pH along the gastrointestinal tract of Japanese medaka by photonic band-gap hydrogel microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Du, Xuemin [Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123 (China); Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Centre for Functional Photonics, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Lei, Ngai-Yu; Hu, Peng [Centre for Functional Photonics, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Lei, Zhang; Ong, Daniel Hock-Chun [Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong (China); Ge, Xuewu [Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123 (China); Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhang, Zhicheng, E-mail: zczhang@ustc.edu.cn [Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123 (China); Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Lam, Michael Hon-Wah, E-mail: bhmhwlam@cityu.edu.hk [Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123 (China); Centre for Functional Photonics, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

    2013-07-17

    Graphical abstract: -- Highlights: •Fabrication of pH-responsive photonic colloidal crystalline microspheres. •Specific photonic band-gap responses occurred in the pH range of 4–5. •Remarkably low in vivo toxicity to Japanese medaka (Oryzia latipes). •In vivo imaging of the morphology and pH along GI tract of Japanese medaka. •Demonstrates bio-imaging potentials of stimuli-responsive photonic materials. -- Abstract: Colloidal crystalline microspheres with photonic band-gap properties responsive to media pH have been developed for in vivo imaging purposes. These colloidal crystalline microspheres were constructed from monodispersed core–shell nano-size particles with poly(styrene-co-acrylic acid) (PS-co-PAA) cores and poly(acrylic acid-co-N-isopropylacrylamide) (PAA-co-PNIPAM) hydrogel shells cross-linked by N,N′-methylenebisacrylamide. A significant shift in the photonic band-gap properties of these colloidal crystalline microspheres was observed in the pH range of 4–5. This was caused by the discontinuous volume phase transition of the hydrogel coating, due to the protonation/deprotonation of its acrylic acid moieties, on the core–shell nano-sized particles within the microspheres. The in vivo imaging capability of these pH-responsive photonic microspheres was demonstrated on a test organism – Japanese medaka, Oryzia latipes – in which the morphology and change in pH along their gastrointestinal (GI) tracts were revealed under an ordinary optical microscope. This work illustrates the potential of stimuli-responsive photonic band-gap materials in tissue-/organ-level in vivo bio-imaging.

  20. Strain-specific variation in a soilborne phytopathogenic fungus for the expression of genes involved in pH signal transduction pathway, pathogenesis and saprophytic survival in response to environmental pH changes.

    Science.gov (United States)

    Daval, Stéphanie; Lebreton, Lionel; Gracianne, Cécile; Guillerm-Erckelboudt, Anne-Yvonne; Boutin, Morgane; Marchi, Muriel; Gazengel, Kévin; Sarniguet, Alain

    2013-12-01

    The soilborne fungus Gaeumannomyces graminis var. tritici (Ggt) causes take-all, a wheat root disease. In an original strain-specific way, a previous study indicates that inside the Ggt species, some strains grow preferentially at acidic pH and other strains at neutral/alkaline pH. The most important mechanism for a fungal response to the environmental pH is the Pal pathway which integrates the products of the six pal genes and the transcription factor PacC. To evaluate whether the Ggt strain-specific growth in function of the ambient pH is mediated via the Pal pathway, a transcriptional study of the genes encoding this pathway was carried out. This study provided the first evidence that the pH signalling pathway similar to those described in other fungi operated in Ggt. The pacC gene was induced at neutral pH whatever the strain. In an original way, the expression of Ggt genes coding for the different Pal proteins depended on the strain and on the ambient pH. In the strain growing better at acidic pH, few pal genes were pH-regulated, and some were overexpressed at neutral pH when regulated. In the strain growing better at neutral pH, underexpression of most of the pal genes at neutral pH occurred. The strains displayed higher gene expression in the ambient pH that unfavoured their growth as if it was a compensation system. All pH taken together, a globally weaker Pal transcript level occurred in the strains that were less sensitive to acidic pH, and on the contrary, the strain growing better on neutral pH showed higher Pal mRNA levels. The expression of genes involved in pathogenesis and saprophytic growth was also regulated by the ambient pH and the strain: each gene displayed a specific pH-regulation that was similar between strains. But all pH taken together, the global transcript levels of four out of six genes were higher in the strain growing better on neutral pH. Altogether, for the first time, the results show that inside a species, conditions affecting

  1. Laryngopharyngeal pH measurement

    OpenAIRE

    Spurrier, E; Clancy, M; Deakin, C

    2004-01-01

    Methods: Cohorts of unconscious adult ED and elective surgical patients were recruited. The posterior pharyngeal wall pH was measured immediately before and after intubation. Pharyngeal pH was used to indicate risk of aspiration, and pH change to assess the efficacy of cricoid pressure.

  2. Increasing surface enhanced Raman spectroscopy effect of RNA and DNA components by changing the pH of silver colloidal suspensions.

    Science.gov (United States)

    Primera-Pedrozo, Oliva M; Rodríguez, Gabriela Del Mar; Castellanos, Jorge; Felix-Rivera, Hilsamar; Resto, Oscar; Hernández-Rivera, Samuel P

    2012-02-15

    This work focused on establishing the parameters for enhancing the Raman signals of DNA and RNA constituents: nitrogenous bases, nucleosides and nucleotides, using metallic nanoparticles as surface enhanced Raman scattering substrates. Silver nanospheres were synthesized using sodium borohydride as a reducing agent and sodium citrate as a capping agent. The prepared nanoparticles had a surface plasmon band at ∼384nm and an average size of 12±3nm. The nanoparticles' surface charge was manipulated by changing the pH of the Ag colloidal suspensions in the range of 1-13. Low concentrations as 0.7μM were detected under the experimental conditions. The optimum pH values were: 7 for adenine, 9 for AMP, 5 for adenosine, 7 for dAMP and 11 for deoxyadenosine.

  3. Electrodialytic remediation of harbour sediment in suspension - Evaluation of effects induced by changes in stirring velocity and current density on heavy metal removal and pH

    DEFF Research Database (Denmark)

    Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.; Villumsen, Arne

    2009-01-01

    Electrodialytic remediation was used to remove heavy metals from a suspension of dredged harbour sediment. The studied metals Cu, Pb, Zn and Cd are normally strongly bound in anoxic sediment. Six electrodialytic laboratory remediation experiments were made, lasting 14 days and under oxic conditions....... The influence on the metal removal was investigated by changing current densities and stirring velocity of the sediment suspension. Using a current density of 1.0 mA/cm2 gave the highest metal removal. The sediment suspension was partly oxidised when mixed into a suspension for the electrodialytic remediation...... experiments and was further oxidised during the experiments. Even at low stirring velocities, oxic conditions were obtained. The metal removal was dependent on the achieved pH in the sediment and the highest metal removal and corresponding low pH was obtained by using a current density of 1.0 mA/cm2...

  4. An integrated spatial snap-shot monitoring method for identifying seasonal changes and spatial changes in surface water quality

    Science.gov (United States)

    Chittoor Viswanathan, Vidhya; Jiang, Yongjun; Berg, Michael; Hunkeler, Daniel; Schirmer, Mario

    2016-08-01

    Integrated catchment-scale management approaches in large catchments are often hindered due to the poor understanding of the spatially and seasonally variable pathways of pollutants. High-frequency monitoring of water quality at random locations in a catchment is resource intensive and challenging. A simplified catchment-scale monitoring approach is developed in this study, for the preliminary identification of water quality changes - Integrated spatial snap-shot monitoring (ISSM). This multi-parameter monitoring approach is applied using the isotopes of water (δ18O-H2O and δD) and nitrate (δ15N-NO3- and δ18O-NO3-) together with the fluxes of nitrate and other solutes, which are used as chemical markers. This method involves selection of few sampling stations, which are identified as the hotspots of water quality changes within the catchment. The study was conducted in the peri-alpine Thur catchment in Switzerland, with two snap-shot campaigns (representative of two widely varying hydrological conditions), in summer 2012 (low flow) and spring 2013 (high flow). Significant spatial (varying with elevation) and seasonal changes in the sources of water were observed between the two seasons. A spatial variation of the sources of nitrate and the solute loads was observed, in tandem with the land use changes in the Thur catchment. There is a seasonal shift in the sources of nitrate, it varies from a strong treated waste water signature during the low flow season to a mixture of other sources (like soil nitrogen derived from agriculture), in the high flow season. This demonstrates the influence of other sources that override the influence of waste water treatment plants (WWTPs) during high flow in the Thur River and its tributaries. This method is expected to be a cost-effective alternative, providing snap-shots, that can help in the preliminary identification of the pathways of solutes and their seasonal/spatial changes in catchments.

  5. Nonparametric Monitoring for Geotechnical Structures Subject to Long-Term Environmental Change

    Directory of Open Access Journals (Sweden)

    Hae-Bum Yun

    2011-01-01

    Full Text Available A nonparametric, data-driven methodology of monitoring for geotechnical structures subject to long-term environmental change is discussed. Avoiding physical assumptions or excessive simplification of the monitored structures, the nonparametric monitoring methodology presented in this paper provides reliable performance-related information particularly when the collection of sensor data is limited. For the validation of the nonparametric methodology, a field case study was performed using a full-scale retaining wall, which had been monitored for three years using three tilt gauges. Using the very limited sensor data, it is demonstrated that important performance-related information, such as drainage performance and sensor damage, could be disentangled from significant daily, seasonal and multiyear environmental variations. Extensive literature review on recent developments of parametric and nonparametric data processing techniques for geotechnical applications is also presented.

  6. Monitoring and Correcting for Response Changes in the CMS Lead-tungstate Electromagnetic Calorimeter

    Science.gov (United States)

    Ferri, Federico

    2012-12-01

    The CMS Electromagnetic Calorimeter (ECAL) comprises 75848 lead-tungstate scintillating crystals. Changes in the ECAL response, due to crystal radiation damage or changes in photo-detector output, are monitored in real time with a sophisticated system of lasers to allow corrections to the energy measurements to be calculated and used. The excellent intrinsic resolution of the CMS ECAL requires the monitoring system itself to be calibrated to a high precision and its stability to be controlled and understood. The components of the CMS ECAL monitoring system, and how it has evolved to include modern solid-state lasers, are described. Several physics channels are exploited to normalise the ECAL response to the changes measured by the monitoring system. These include low energy diphoton resonances, electrons from W and Z decays (using shower energy versus track momentum measurements), and the azimuthal symmetry of low energy deposits in minimum bias events. This paper describes how the monitoring system is operated, how the corrections are obtained, and the resulting ECAL performance.

  7. The influence of small-scale circum-neutral pH change on Cu-bioavailability and toxicity to an estuarine bivalve (Austriella cf plicifera) in whole-sediment toxicity tests

    Energy Technology Data Exchange (ETDEWEB)

    Hutchins, Colin M. [Australian Rivers Institute, Griffith University, PMB 50, Gold Coast Mail Centre, Queensland 9726 (Australia)], E-mail: colin.hutchins@umontreal.ca; Teasdale, Peter R.; Yip Lee, Shing [Australian Rivers Institute, Griffith University, PMB 50, Gold Coast Mail Centre, Queensland 9726 (Australia); Simpson, Stuart L. [Centre for Environmental Contaminants Research, CSIRO Land and Water, Private Mailbag 7, Bangor, NSW 2234 (Australia)

    2008-11-01

    In whole-sediment toxicity tests employing metal-spiked sediment, pH is a crucial determinant of sediment geochemistry, sediment-porewater metal partitioning and metal bioavailability to benthic organisms. Small pH changes in metal-spiked sediment may therefore have important implications for toxicity to organisms. The present study evaluated the effect of small-scale pH changes (pH 6.6, 7.2, 7.6) in Cu-spiked sediment on metal bioavailability and subsequent organism response. Variation of pH produced distinct changes in sediment geochemistry. Increasing pH from 6.6 to 7.6 resulted in lower redox potential, greater acid volatile sulfide (AVS) formation, and lower partitioning of Cu, Fe and Mn to the porewater. The minor pH changes and associated variation in sediment geochemistry modified reburial rates and copper accumulation by the bivalve, Austriella cf plicifera. Bivalve reburial was slowest for the 1400 {mu}g g{sup -1} Cu-spiked pH 6.6 sediment, in which porewater copper concentrations exceeded 50 {mu}g L{sup -1}. Bivalve reburial was higher for pH 7.2 Cu-spiked sediments at all concentrations of copper investigated than in pH 6.6 and 7.6 sediments, where reburial rates were similar. Higher levels of bivalve activity suggest that A. cf plicifera may have an optimal pH range in the vicinity of pH 7.2. Tissue Cu concentrations varied with pH and appear dependent on spiked Cu concentration and organism activity. Strong linear correlations of tissue Cu concentration with all three Cu phases (overlying water, porewater and particulate phases), however, limited the ability to accurately determine the source of Cu uptake.

  8. Estimating changes in cardiac output using an implanted hemodynamic monitor in heart failure patients

    DEFF Research Database (Denmark)

    Ståhlberg, Marcus; Damgaard, Morten; Ersgård, David;

    2010-01-01

    OBJECTIVES: The aim of this study was to evaluate an algorithm that estimates changes in cardiac output (CO) from right ventricular (RV) pressure waveforms derived from an implantable hemodynamic monitor (IHM) in heart failure patients. DESIGN: Twelve heart failure patients (NYHA II-III, EF 32......%) with an implantable hemodynamic monitor (Chronicle) were included in this study. Changes in cardiac output were provoked by body position change at rest (left lateral supine, horizontal supine, sitting, and standing) and a steady state bicycle exercise at 20 watts. Estimated CO derived from the IHM (CO...... was -0.39 L/min (11%). Limits of agreement were +/-1.56 L/min and relative error was 21%. CONCLUSIONS: A simple algorithm based on RV pressure wave form characteristics derived from an IHM can be used to estimate changes in CO in heart failure patients. These findings encourage further research aiming...

  9. CTFS/ForestGEO: A global network to monitor forest interactions with a changing climate

    Science.gov (United States)

    Anderson-Teixeira, K. J.; Muller-Landau, H.; McMahon, S.; Davies, S. J.

    2013-12-01

    Forests are an influential component of the global carbon cycle and strongly influence Earth's climate. Climate change is altering the dynamics of forests globally, which may result in significant climate feedbacks. Forest responses to climate change entail both short-term ecophysiological responses and longer-term directional shifts in community composition. These short- and long-term responses of forest communities to climate change may be better understood through long-term monitoring of large forest plots globally using standardized methodology. Here, we describe a global network of forest research plots (CTFS/ForestGEO) of utility for understanding forest responses to climate change and consequent feedbacks to the climate system. CTFS/ForestGEO is an international network consisting of 51 sites ranging in size from 2-150 ha (median size: 25 ha) and spanning from 25°S to 52°N latitude. At each site, every individual > 1cm DBH is mapped and identified, and recruitment, growth, and mortality are monitored every 5 years. Additional measurements include aboveground productivity, carbon stocks, soil nutrients, plant functional traits, arthropod and vertebrates monitoring, DNA barcoding, airborne and ground-based LiDAR, micrometeorology, and weather monitoring. Data from this network are useful for understanding how forest ecosystem structure and function respond to spatial and temporal variation in abiotic drivers, parameterizing and evaluating ecosystem and earth system models, aligning airborne and ground-based measurements, and identifying directional changes in forest productivity and composition. For instance, CTFS/ForestGEO data have revealed that solar radiation and night-time temperature are important drivers of aboveground productivity in moist tropical forests; that tropical forests are mixed in terms of productivity and biomass trends over the past couple decades; and that the composition of Panamanian forests has shifted towards more drought

  10. Good Practice in Designing and Implementing National Monitoring Systems for Adaptation to Climate Change

    DEFF Research Database (Denmark)

    Naswa, Prakriti; Trærup, Sara Lærke Meltofte; Bouroncle, Claudia

    In this report, we identify, analyse and compare international good practices in the design and implementation of national monitoring and evaluating indicator systems for climate change adaptation. This first chapter provides an introduction to the context and key terminology in the domain...

  11. A Linguistic Communication Measure for Monitoring Changes in Chinese Aphasic Narrative Production

    Science.gov (United States)

    Kong, Anthony Pak-Hin; Law, Sam-Po

    2009-01-01

    This study investigated the usefulness of the Cantonese Linguistic Communication Measure (CLCM) in monitoring changes of narrative production in five Chinese adults with aphasia in the period of spontaneous recovery (SR group) and four who underwent anomia therapies (Tx group). Language samples elicited from a picture description task were…

  12. Methods of soil resampling to monitor changes in the chemical concentrations of forest soils

    Science.gov (United States)

    Lawrence, Gregory B.; Fernandez, Ivan J.; Hazlett, Paul W.; Bailey, Scott W.; Ross, Donald S.; Villars, Thomas R.; Quintana, Angelica; Ouimet, Rock; McHale, Michael; Johnson, Chris E.; Briggs, Russell D.; Colter, Robert A.; Siemion, Jason; Bartlett, Olivia L.; Vargas, Olga; Antidormi, Michael; Koppers, Mary Margaret

    2016-01-01

    Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental changes. Repeated sampling to monitor these changes in forest soils is a relatively new practice that is not well documented in the literature and has only recently been broadly embraced by the scientific community. The objective of this protocol is therefore to synthesize the latest information on methods of soil resampling in a format that can be used to design and implement a soil monitoring program. Successful monitoring of forest soils requires that a study unit be defined within an area of forested land that can be characterized with replicate sampling locations. A resampling interval of 5 years is recommended, but if monitoring is done to evaluate a specific environmental driver, the rate of change expected in that driver should be taken into consideration. Here, we show that the sampling of the profile can be done by horizon where boundaries can be clearly identified and horizons are sufficiently thick to remove soil without contamination from horizons above or below. Otherwise, sampling can be done by depth interval. Archiving of sample for future reanalysis is a key step in avoiding analytical bias and providing the opportunity for additional analyses as new questions arise.

  13. So much data, so little time: Using sequential data analysis to monitor behavioral changes.

    Science.gov (United States)

    Walker, Tywanquila

    2016-01-01

    Twenty-three infants (M = 13.7 months, SD = 3.73) and their primary caregivers were observed and video-taped in three 20-min play sessions. Over the course of a month, changes in infant behaviors and caregiver responsiveness to those behaviors were monitored. Repeated-measures ANOVAs indicated that caregiver responsiveness to infant object-related and dyadic behaviors significantly increased over the course of the sessions. However, the ANOVAs did not specify exactly which caregiver behaviors changed. Sequential data analysis revealed that caregivers specifically increased their use of dyadic vocal behaviors in response to all infant behaviors. This study reveals that although ANOVAs are useful for providing information about macro, overall changes in caregiver behavior, sequential data analysis is a useful tool for evaluating micro, moment-to-moment changes in behavior. With sequential analysis, specific behavioral patterns can be examined and, if necessary, steps can be taken to modify and monitor those behaviors over time. •Sequential data analysis was used to monitor changes in caregiver behavior.•Non-culture-specific behavioral codes and techniques were used to quantify caregiver responsiveness to infant object-related and dyadic behaviors.•When compared to ANOVA, sequential data analysis is more useful for assessing micro-level behavioral changes in infant-caregiver interactions.

  14. Monitoring land cover changes in Isfahan Province, Iran using Landsat satellite data.

    Science.gov (United States)

    Soffianian, Alireza; Madanian, Maliheh

    2015-08-01

    Changes in land cover and land use reveal the effects of natural and human processes on the Earth's surface. These changes are predicted to exert the greatest environmental impacts in the upcoming decades. The purpose of the present study was to monitor land cover changes using Multispectral Scanner Sensor (MSS) and multitemporal Landsat Thematic Mapper (TM) data from the counties of Isfahan Province, Iran, during 1975, 1990, and 2010. The maximum likelihood supervised classification method was applied to map land cover. Postclassification change detection technique was also used to produce change images through cross-tabulation. Classification results were improved using ancillary data, visual interpretation, and local knowledge about the area. The overall accuracy of land cover change maps ranged from 88 to 90.6%. Kappa coefficients associated with the classification were 0.81 for 1975, 0.84 for 1990, and 0.85 for 2010 images. This study monitored changes related to conversion of agricultural land to impervious surfaces, undeveloped land to agricultural land, agricultural land to impervious surfaces, and undeveloped land to impervious surfaces. The analyses of land cover changes during the study period revealed the significant development of impervious surfaces in counties of Isfahan Province as a result of population growth, traffic conditions, and industrialization. The image classification indicated that agricultural lands increased from 2520.96 km(2) in 1975 to 4103.85 km(2) in 2010. These land cover changes were evaluated in different counties of Isfahan Province.

  15. Using community trait-distributions to assign microbial responses to pH changes and Cd in forest soils treated with wood ash

    DEFF Research Database (Denmark)

    Cruz Paredes, Carla; Wallander, Håkan; Kjøller, Rasmus

    2017-01-01

    H and Cd, and (iii) consequences for proxies of the function soil organic matter (SOM) turnover including respiration and microbial growth rates. Two sets of field-experiments in temperate conifer forest plantations were combined with laboratory microcosm experiments where wood ash additions were compared...... to additions of lime and Cd. Wood ash induced structural changes in the microbial community in both field experiments, and striking similarities were observed between the application of ash and that of lime in the microcosm experiments. Wood ash increased pH, and led to a shift toward faster SOM decomposition...

  16. Study of the crystallographic phase change on copper (I) selenide thin films prepared through chemical bath deposition by varying the pH of the solution

    Science.gov (United States)

    Sandoval-Paz, M. G.; Rodríguez, C. A.; Porcile-Saavedra, P. F.; Trejo-Cruz, C.

    2016-07-01

    Copper (I) selenide thin films with orthorhombic and cubic structure were deposited on glass substrates by using the chemical bath deposition technique. The effects of the solution pH on the films growth and subsequently the structural, optical and electrical properties of the films were studied. Films with orthorhombic structure were obtained from baths wherein both metal complex and hydroxide coexist; while films with cubic structure were obtained from baths where the metal hydroxide there is no present. The structural modifications are accompanied by changes in bandgap energy, morphology and electrical resistivity of the films.

  17. Design of ecoregional monitoring in conservation areas of high-latitude ecosystems under contemporary climate change

    Science.gov (United States)

    Beever, Erik A.; Woodward, Andrea

    2011-01-01

    Land ownership in Alaska includes a mosaic of federally managed units. Within its agency’s context, each unit has its own management strategy, authority, and resources of conservation concern, many of which are migratory animals. Though some units are geographically isolated, many are nevertheless linked by paths of abiotic and biotic flows, such as rivers, air masses, flyways, and terrestrial and aquatic migration routes. Furthermore, individual land units exist within the context of a larger landscape pattern of shifting conditions, requiring managers to understand at larger spatial scales the status and trends in the synchrony and spatial concurrence of species and associated suitable habitats. Results of these changes will determine the ability of Alaska lands to continue to: provide habitat for local and migratory species; absorb species whose ranges are shifting northward; and experience mitigation or exacerbation of climate change through positive and negative atmospheric feedbacks. We discuss the geographic and statutory contexts that influence development of ecological monitoring; argue for the inclusion of significant amounts of broad-scale monitoring; discuss the importance of defining clear programmatic and monitoring objectives; and draw from lessons learned from existing long-term, broad-scale monitoring programs to apply to the specific contexts relevant to high-latitude protected areas such as those in Alaska. Such areas are distinguished by their: marked seasonality; relatively large magnitudes of contemporary change in climatic parameters; and relative inaccessibility due to broad spatial extent, very low (or zero) road density, and steep and glaciated areas. For ecological monitoring to effectively support management decisions in high-latitude areas such as Alaska, a monitoring program ideally would be structured to address the actual spatial and temporal scales of relevant processes, rather than the artificial boundaries of individual land

  18. Characterizing Forest Change Using Community-Based Monitoring Data and Landsat Time Series.

    Science.gov (United States)

    DeVries, Ben; Pratihast, Arun Kumar; Verbesselt, Jan; Kooistra, Lammert; Herold, Martin

    2016-01-01

    Increasing awareness of the issue of deforestation and degradation in the tropics has resulted in efforts to monitor forest resources in tropical countries. Advances in satellite-based remote sensing and ground-based technologies have allowed for monitoring of forests with high spatial, temporal and thematic detail. Despite these advances, there is a need to engage communities in monitoring activities and include these stakeholders in national forest monitoring systems. In this study, we analyzed activity data (deforestation and forest degradation) collected by local forest experts over a 3-year period in an Afro-montane forest area in southwestern Ethiopia and corresponding Landsat Time Series (LTS). Local expert data included forest change attributes, geo-location and photo evidence recorded using mobile phones with integrated GPS and photo capabilities. We also assembled LTS using all available data from all spectral bands and a suite of additional indices and temporal metrics based on time series trajectory analysis. We predicted deforestation, degradation or stable forests using random forest models trained with data from local experts and LTS spectral-temporal metrics as model covariates. Resulting models predicted deforestation and degradation with an out of bag (OOB) error estimate of 29% overall, and 26% and 31% for the deforestation and degradation classes, respectively. By dividing the local expert data into training and operational phases corresponding to local monitoring activities, we found that forest change models improved as more local expert data were used. Finally, we produced maps of deforestation and degradation using the most important spectral bands. The results in this study represent some of the first to combine local expert based forest change data and dense LTS, demonstrating the complementary value of both continuous data streams. Our results underpin the utility of both datasets and provide a useful foundation for integrated forest

  19. Perspectives on monitoring gradual change across the continuity of Landsat sensors using time-series data

    Science.gov (United States)

    Vogelmann, James; Gallant, Alisa L.; Shi, Hua; Zhu, Zhe

    2016-01-01

    There are many types of changes occurring over the Earth's landscapes that can be detected and monitored using Landsat data. Here we focus on monitoring “within-state,” gradual changes in vegetation in contrast with traditional monitoring of “abrupt” land-cover conversions. Gradual changes result from a variety of processes, such as vegetation growth and succession, damage from insects and disease, responses to shifts in climate, and other factors. Despite the prevalence of gradual changes across the landscape, they are largely ignored by the remote sensing community. Gradual changes are best characterized and monitored using time-series analysis, and with the successful launch of Landsat 8 we now have appreciable data continuity that extends the Landsat legacy across the previous 43 years. In this study, we conducted three related analyses: (1) comparison of spectral values acquired by Landsats 7 and 8, separated by eight days, to ensure compatibility for time-series evaluation; (2) tracking of multitemporal signatures for different change processes across Landsat 5, 7, and 8 sensors using anniversary-date imagery; and (3) tracking the same type of processes using all available acquisitions. In this investigation, we found that data representing natural vegetation from Landsats 5, 7, and 8 were comparable and did not indicate a need for major modification prior to use for long-term monitoring. Analyses using anniversary-date imagery can be very effective for assessing long term patterns and trends occurring across the landscape, and are especially good for providing insights regarding trends related to long-term and continuous trends of growth or decline. We found that use of all available data provided a much more comprehensive level of understanding of the trends occurring, providing information about rate, duration, and intra- and inter-annual variability that could not be readily gleaned from the anniversary date analyses. We observed that using all

  20. Ecoregional-scale monitoring within conservation areas, in a rapidly changing climate

    Science.gov (United States)

    Beever, Erik A.; Woodward, Andrea

    2011-01-01

    Long-term monitoring of ecological systems can prove invaluable for resource management and conservation. Such monitoring can: (1) detect instances of long-term trend (either improvement or deterioration) in monitored resources, thus providing an early-warning indication of system change to resource managers; (2) inform management decisions and help assess the effects of management actions, as well as anthropogenic and natural disturbances; and (3) provide the grist for supplemental research on mechanisms of system dynamics and cause-effect relationships (Fancy et al., 2009). Such monitoring additionally provides a snapshot of the status of monitored resources during each sampling cycle, and helps assess whether legal standards and regulations are being met. Until the last 1-2 decades, tracking and understanding changes in condition of natural resources across broad spatial extents have been infrequently attempted. Several factors, however, are facilitating the achievement of such broad-scale investigation and monitoring. These include increasing awareness of the importance of landscape context, greater prevalence of regional and global environmental stressors, and the rise of landscape-scale programs designed to manage and monitor biological systems. Such programs include the US Forest Service's Forest Inventory and Analysis (FIA) Program (Moser et al., 2008), Canada's National Forest Inventory, the 3Q Programme for monitoring agricultural landscapes of Norway (Dramstad et al., 2002), and the emerging (US) Landscape Conservation Cooperatives (USDOI Secretarial Order 3289, 2009; Anonymous, 2011). This Special Section explores the underlying design considerations, as well as many pragmatic aspects associated with program implementation and interpretation of results from broad-scale monitoring systems, particularly within the constraints of high-latitude contexts (e.g., low road density, short field season, dramatic fluctuations in temperature). Although Alaska is

  1. A novel framework of change-point detection for machine monitoring

    Science.gov (United States)

    Lu, Guoliang; Zhou, Yiqi; Lu, Changhou; Li, Xueyong

    2017-01-01

    The need for automatic machine monitoring has been well known in industries for many years. Although it has been widely accepted that a change in the structural property can indicate the fault in rotating machinery components (e.g., bearing and gears), automatic algorithms for this task are still in progress. In this paper, we propose a novel framework for change-point detection in machine monitoring. The framework includes two phases: (1) anomaly measure: on the basis of an automatic regression (AR) model, a new computation method is proposed to measure anomalies in a given time series which does not require any reference data from other measurement(s); (2) change detection: a new statistical test is employed by using martingale for detecting a potential change in the series which can be operated in an unsupervised and self-conducted manner. Experimental results on testing data captured in real scenarios demonstrated the effectiveness and the realizability of the proposed framework for change-point detection in machine monitoring, which suggests that our framework can be directly applicable in many real-world applications.

  2. Using Vis-NIR spectroscopy for monitoring temporal changes of soil organic carbon

    DEFF Research Database (Denmark)

    Deng, Fan; Minasny, Budiman; Knadel, Maria

    2013-01-01

    Monitoring the spatial and temporal changes in soil organic carbon (SOC) brought about by climate change and agricultural practices is challenging because existing SOC monitoring methods are very time and resource consuming. This study examined the use of visible near-infrared spectroscopy (Vis....... For subsoil samples, the ability of Vis-NIR to predict SOC levels varied. In West Jutland, Central Jutland, North Jutland, and Thy, Vis-NIR-predicted SOC levels did not differ from TL-measured levels, showing good predictive ability. For topsoil samples, the spatial pattern of change in TL....... Some difficulties can arise in low SOC subsoils, so more systematic work is needed to improve the method for practical applications....

  3. Applications of Advanced Technology for Monitoring Forest Carbon to Support Climate Change Mitigation

    Science.gov (United States)

    Birdsey, R.; Hurtt, G. C.; Dubayah, R.; Hagen, S. C.; Vargas, R.; Nehrkorn, T.; Domke, G. M.; Houghton, R. A.

    2015-12-01

    Measurement, Reporting, and Verification (MRV) is a broad concept guiding the application of monitoring technology to the needs of countries or entities for reporting and verifying reductions in greenhouse gas emissions or increases in greenhouse gas sinks. Credibility, cost-effectiveness, and compatibility are important features of global MRV efforts that can support implementation of climate change mitigation programs such as Reducing Emissions from Deforestation and Forest Degradation and Sustainable Forest Management (REDD+). Applications of MRV technology may be tailored to individual country circumstances following guidance provided by the Intergovernmental Panel on Climate Change; hence, there is no single approach that is uniquely viable but rather a range of ways to integrate new MRV methods. MRV technology is advancing rapidly with new remote sensing and advanced measurement of atmospheric CO2, and in situ terrestrial and ocean measurements, coupled with improvements in data analysis, modeling, and assessing uncertainty. Here we briefly summarize some of the most application-ready MRV technologies being developed under NASA's Carbon Monitoring System (CMS) program, and illustrate how these technologies may be applied for monitoring forests using several case studies that span a range of scales, country circumstances, and stakeholder reporting requirements. We also include remarks about the potential role of advanced monitoring technology in the context of the global climate accord that is expected to result from the 21st session of the Conference of the Parties to the United Nations Framework Convention on Climate Change, which is expected to take place in December 2015, in Paris, France.

  4. MRI monitoring of pathological changes in the spinal cord in patients with multiple sclerosis

    DEFF Research Database (Denmark)

    Gass, Achim; Rocca, Maria A; Agosta, Federica;

    2015-01-01

    The spinal cord is a clinically important site that is affected by pathological changes in most patients with multiple sclerosis; however, imaging of the spinal cord with conventional MRI can be difficult. Improvements in MRI provide a major advantage for spinal cord imaging, with better signal......, functional MRI, and proton magnetic resonance spectroscopy, can detect non-focal, spinal cord pathological changes in patients with multiple sclerosis. Additionally, functional MRI can reveal changes in the response pattern to sensory stimulation in patients with multiple sclerosis. Through use...... with cord atrophy markers seem to be the most robust and meaningful biomarkers to monitor disease evolution in early multiple sclerosis....

  5. A ph sensor based on a flexible substrate

    Science.gov (United States)

    Huang, Wen-Ding

    implanted inside the esophagus. Our pH electrode can monitor the pH changes of gastric juice in real time when the reflux happening in the esophagus. Our micro flexible pH sensor performed clear responses in each distinct pH reflux episode quickly and accurately comparing with the other commercial pH monitoring system. For the food freshness monitoring applications, we used the flexible pH sensor as a freshness indicator to monitor the pH changing profile during the food spoilage procedure. The sensor was then embedded with radio frequency identification (RFID) based passive telemetry enabling remote monitoring of food freshness. In the result, our pH-wireless RFID system presented 633Hz/pH of the sensitivity in the frequency calibration. The calibration of stability and dynamical response of the RFID system were also demonstrated before the test on food freshness monitoring. Finally, a white fish meat for long term spoilage procedure monitoring was applied and tested by using our wireless IrOx pH sensing system. Our RFID pH sensing module is able to monitor, collect and transmit the pH information continuously for 18 hours during the food spoilage procedure. In this dissertation, a micro size of IrOx/AgCl pH sensor was fabricated on a flexible substrate. The physical properties of the IrO x thin film was verified in the work. The different sensing capability such as the sensitivity, stability, reversibility, response time, repeatability, selectivity, and temperature dependence was then demonstrated in this work. After the different in-vitro tests, the pH sensor were embedded with our passive RFID circuitry for the in-vivo GERD diagnosis and food freshness monitoring application. Our wireless pH sensing system was able to deliver the accurate and quick pH sensing data wirelessly. In conclusion, our deformable IrOx pH electrodes have been demonstrated with the advantages of accommodating and conforming sensors in small spaces or curved surfaces. This miniature IrOx pH sensor

  6. Enzyme-regulated the changes of pH values for assembling a colorimetric and multistage interconnection logic network with multiple readouts

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yanyan; Ran, Xiang; Lin, Youhui [Laboratory of Chemical Biology, Division of Biological Inorganic Chemistry, State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Graduate School of University of Chinese Academy of Sciences, Beijing 100039 (China); Ren, Jinsong, E-mail: jren@ciac.ac.cn [Laboratory of Chemical Biology, Division of Biological Inorganic Chemistry, State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China); Qu, Xiaogang [Laboratory of Chemical Biology, Division of Biological Inorganic Chemistry, State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China)

    2015-04-22

    Highlights: • A colorimetric and multistage biological network has been developed. • This system was on the basis of the enzyme-regulated changes of pH values. • This enzyme-based system could assemble large biological circuit. • Two signal transducers (DNA/AuNPs and acid–base indicators) were used. • The compositions of samples could be detected through visual output signals. - Abstract: Based on enzymatic reactions-triggered changes of pH values and biocomputing, a novel and multistage interconnection biological network with multiple easy-detectable signal outputs has been developed. Compared with traditional chemical computing, the enzyme-based biological system could overcome the interference between reactions or the incompatibility of individual computing gates and offer a unique opportunity to assemble multicomponent/multifunctional logic circuitries. Our system included four enzyme inputs: β-galactosidase (β-gal), glucose oxidase (GOx), esterase (Est) and urease (Ur). With the assistance of two signal transducers (gold nanoparticles and acid–base indicators) or pH meter, the outputs of the biological network could be conveniently read by the naked eyes. In contrast to current methods, the approach present here could realize cost-effective, label-free and colorimetric logic operations without complicated instrument. By designing a series of Boolean logic operations, we could logically make judgment of the compositions of the samples on the basis of visual output signals. Our work offered a promising paradigm for future biological computing technology and might be highly useful in future intelligent diagnostics, prodrug activation, smart drug delivery, process control, and electronic applications.

  7. Monitoring Groundwater-Storage Change and Land Subsidence in the Tucson Active Management Area, Arizona

    Science.gov (United States)

    Kahler, E.; Carruth, R. L.; Conway, B. D.

    2016-12-01

    The U.S. Geological Survey monitors groundwater-storage change and land subsidence caused by groundwater withdrawal in the Tucson Basin and Avra Valley—the two most populated alluvial basins within the Tucson Active Management Area. The primary management goal of the Tucson Active Management Area is safe-yield by the year 2025. A number of hydrogeologic investigations are ongoing including 1) monitoring groundwater-storage change and land subsidence at a network of stations in the Tucson Basin and Avra Valley, 2) maintaining a network of vertical extensometers for continuous monitoring aquifer compaction and water level, and 3) microgravity and GPS surveys every 1-3 years from 1997 to the present, with the addition of annual InSAR data beginning in 2000. Temporal microgravity surveys are used to detect local changes in the gravitational field of the Earth through time. The gravity changes are used to infer groundwater-storage change in Tucson Basin and Avra Valley where significant variations in pore-space (water mass) storage occur—this results from groundwater mining, artificial recharge, and periodic natural recharge events. Groundwater-storage change is an important, but typically poorly quantified component of the groundwater budget in alluvial basins, including Tucson Basin and Avra Valley. In areas where water-level elevation data are available, estimates of aquifer-storage properties also are estimated by dividing the volume of aquifer-storage change (measured with gravity methods) by the water-level elevation change in the aquifer. Results of the monitoring show that while increases in gravity and water-level rise occur following large natural recharge events and near areas where artificial recharge is occurring, overall declining gravity reflects general overdraft conditions. However, the rate of overdraft has decreased from 25,000-50,000 acre-feet per year from 2000 to 2006, to less than 25,000 acre- feet per year from 2006 to the present

  8. Monitoring of shoreline changes using remote sensing (case study: coastal city of Bandar Abbas)

    Science.gov (United States)

    Tamassoki, E.; Amiri, H.; Soleymani, Z.

    2014-06-01

    Shoreline change is one of the most common natural processes that prevail upon coastal areas. The most important aspect of managing coastal areas is identifying the location and change over time of shoreline. This requires frequent monitoring of the shoreline using satellite imagery over time. We have used imagery from the Landsat TM-5 sensor from 1984,1998 and 2009 in order to monitor shoreline changes using the Max Likelihood Classification method (MLC) in Bandar Abbas city. Monitoring showed that during the period from 1984 to 1998 the area of coastline of Bandar Abbas increased 804.09 hectares. The increase over the next 11-year period was as less, at only 140.81 hectares. In 2009 there was a drastic decrease in shoreline, with the total length of shoreline decreasing from 330 km to 271 km during the period from 1984 to 2009.Results showed that in each period in which the area of coastline advanced, changes in length of shoreline had been less prominent.

  9. Nutrient leaching, soil pH and changes in microbial community increase with time in lead-contaminated boreal forest soil at a shooting range area.

    Science.gov (United States)

    Selonen, Salla; Setälä, Heikki

    2017-02-01

    Despite the known toxicity of lead (Pb), Pb pellets are widely used at shotgun shooting ranges over the world. However, the impacts of Pb on soil nutrients and soil microbes, playing a crucial role in nutrient cycling, are poorly understood. Furthermore, it is unknown whether these impacts change with time after the cessation of shooting. To shed light on these issues, three study sites in the same coniferous forest in a shooting range area were studied: an uncontaminated control site and an active and an abandoned shooting range, both sharing a similar Pb pellet load in the soil, but the latter with a 20-year longer contamination history. Soil pH and nitrate concentration increased, whilst soil phosphate concentration and fungal phospholipid fatty acid (PLFA) decreased due to Pb contamination. Our results imply that shooting-derived Pb can influence soil nutrients and microbes not only directly but also indirectly by increasing soil pH. However, these mechanisms cannot be differentiated here. Many of the Pb-induced changes were most pronounced at the abandoned range, and nutrient leaching was increased only at that site. These results suggest that Pb disturbs the structure and functions of the soil system and impairs a crucial ecosystem service, the ability to retain nutrients. Furthermore, the risks of shooting-derived Pb to the environment increase with time.

  10. Precipitation-Induced Changes in Microstrain and Its Relation with Hardness and Tempering Parameter in 17-4 PH Stainless Steel

    Science.gov (United States)

    Mahadevan, S.; Manojkumar, R.; Jayakumar, T.; Das, C. R.; Rao, B. P. C.

    2016-06-01

    17-4 PH (precipitation hardening) stainless steel is a soft martensitic stainless steel strengthened by aging at appropriate temperature for sufficient duration. Precipitation of copper particles in the martensitic matrix during aging causes coherency strains which improves the mechanical properties, namely hardness and strength of the matrix. The contributions to X-ray diffraction (XRD) profile broadening due to coherency strains caused by precipitation and crystallite size changes due to aging are separated and quantified using the modified Williamson-Hall approach. The estimated normalized mean square strain and crystallite size are used to explain the observed changes in hardness. Microstructural changes observed in secondary electron images are in qualitative agreement with crystallite size changes estimated from XRD profile analysis. The precipitation kinetics in the age-hardening regime and overaged regime are studied from hardness changes and they follow the Avrami kinetics and Wilson's model, respectively. In overaged condition, the hardness changes are linearly correlated to the tempering parameter (also known as Larson-Miller parameter). Similar linear variation is observed between the normalized mean square strain (determined from XRD line profile analysis) and the tempering parameter, in the incoherent regime which is beyond peak microstrain conditions.

  11. Conformational changes in proteins recovered from jumbo squid (Dosidicus gigas) muscle through pH shift washing treatments.

    Science.gov (United States)

    Cortés-Ruiz, Juan A; Pacheco-Aguilar, Ramón; Ramírez-Suárez, Juan C; Lugo-Sánchez, Maria E; García-Orozco, Karina D; Sotelo-Mundo, Rogerio R; Peña-Ramos, Aida

    2016-04-01

    Conformational and thermal-rheological properties of acidic (APC) and neutral (NPC) protein concentrates were evaluated and compared to those of squid (Dosidicus gigas) muscle proteins (SM). Surface hydrophobicity, sulfhydryl status, secondary structure profile, differential scanning calorimetry and oscillatory dynamic rheology were used to evaluate the effect of treatments on protein properties. Acidic condition during the washing process (APC) promoted structural and conformational changes in the protein present in the concentrate produced. These changes were enhanced during the heat setting of the corresponding sol. Results demonstrate that washing squid muscle under the proposed acidic conditions is a feasible technological alternative for squid-based surimi production improving its yield and gel-forming ability.

  12. Effects of branch solid Fe sulphate implants on xylem sap composition in field-grown peach and pear: changes in Fe, organic anions and pH.

    Science.gov (United States)

    Larbi, Ajmi; Morales, Fermín; Abadía, Javier; Abadía, Anunciación

    2003-12-01

    The effects of placing solid implants containing Fe sulfate in branches of Fe-deficient pear and peach trees on the composition of the xylem sap have been studied. Iron sulfate implants are commercially used in northeastern Spain to control iron chlorosis in fruit trees. Implants increased Fe concentrations and decreased organic acid concentrations in the xylem sap, whereas xylem sap pH was only moderately changed. The citrate to Fe ratios decreased markedly after implants, therefore improving the possibility that Fe could be reduced by the leaf plasma membrane enzyme reductase, known to be inhibited by high citrate/Fe ratios. In peach, the effects of the implants could be observed many months post treatment. In pear, some effects were still observed one year after the implants had taken place. Results obtained indicate that solid Fe sulfate implants were capable of significantly changing the chemical composition of the xylem sap in fruit trees.

  13. Non-destructive sensing of the freshness of packed cod fish using conductivity and pH electrodes

    NARCIS (Netherlands)

    Heising, J.K.; Bartels, P.V.; Boekel, van M.A.J.S.; Dekker, M.

    2014-01-01

    The use of pH and conductivity electrodes as non-destructive methods for monitoring changes in the freshness status of packed fish is explored. The electrodes monitor changes in the electrical properties of an aqueous phase positioned in the headspace of the fish package. Volatile compounds produced

  14. Non-destructive sensing of the freshness of packed cod fish using conductivity and pH electrodes

    NARCIS (Netherlands)

    Heising, J.K.; Bartels, P.V.; Boekel, van M.A.J.S.; Dekker, M.

    2014-01-01

    The use of pH and conductivity electrodes as non-destructive methods for monitoring changes in the freshness status of packed fish is explored. The electrodes monitor changes in the electrical properties of an aqueous phase positioned in the headspace of the fish package. Volatile compounds produced

  15. CTFS-ForestGEO: a worldwide network monitoring forests in an era of global change

    Energy Technology Data Exchange (ETDEWEB)

    Anderson-Teixeira, Kristina J. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Davies, Stuart J. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; National Museum of Natural History, Washington, DC (United States). Dept. of Botany; Bennett, Amy C. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Gonzalez-Akre, Erika B. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Muller-Landau, Helene C. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Joseph Wright, S. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Abu Salim, Kamariah [Univ. of Brunei Darussalam, Bandar Seri Begawan (Brunei). Faculty of Science. Environmental and Life Sciences; Almeyda Zambrano, Angélica M. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Stanford Univ., CA (United States). Stanford Woods Inst. for the Environment; Univ. of Alabama, Tuscaloosa, AL (United States). Dept. of Geography; Alonso, Alfonso [Smithsonian Conservation Biology Inst., Washington, DC (United States). National Zoological Park. Center for Conservation Education and Sustainability; Baltzer, Jennifer L. [Wilfrid Laurier Univ., Waterloo, ON (Canada). Dept. of Biology; Basset, Yves [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Bourg, Norman A. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Broadbent, Eben N. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Stanford Univ., CA (United States). Stanford Woods Inst. for the Environment; Univ. of Alabama, Tuscaloosa, AL (United States). Dept. of Geography; Brockelman, Warren Y. [Mahidol Univ., Bangkok (Thailand). Dept. of Biology; Bunyavejchewin, Sarayudh [Dept. of National Parks, Wildlife and Plant Conservation, Bangkok (Thailand). Research Office; Burslem, David F. R. P. [Univ. of Aberdeen (United Kingdom). School of Biological Sciences; Butt, Nathalie [Univ. of Queensland, St. Lucia (Australia). School of Biological Sciences; Univ. of Oxford (United Kingdom). School of Geography and the Environment. Environmental Change Inst.; Cao, Min [Chinese Academy of Sciences (CAS), Kunming (China). Xishuangbanna Tropical Botanical Garden. Key Lab. of Tropical Forest Ecology; Cardenas, Dairon [Sinchi Amazonic Inst. of Scientific Research, Bogota (Colombia); Chuyong, George B. [Univ. of Buea (Cameroon). Dept. of Botany and Plant Physiology; Clay, Keith [Indiana Univ., Bloomington, IN (United States). Dept. of Biology; Cordell, Susan [USDA Forest Service, Hilo, HI (United States). Inst. of Pacific Islands Forestry; Dattaraja, Handanakere S. [Indian Inst. of Science, Bangalore (India). Centre for Ecological Sciences; Deng, Xiaobao [Chinese Academy of Sciences (CAS), Kunming (China). Xishuangbanna Tropical Botanical Garden. Key Lab. of Tropical Forest Ecology; Detto, Matteo [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Du, Xiaojun [Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Botany; Duque, Alvaro [Univ. Nacional de Colombia, Medellin (Colombia). Dept. de Ciencias Forestales; Erikson, David L. [National Museum of Natural History, Washington, DC (United States). Dept. of Botany

    2014-09-25

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services, including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamic research sites useful for characterizing forest responses to global change. The broad suite of measurements made at the CTFS-ForestGEO sites make it possible to investigate the complex ways in which global change is impacting forest dynamics. ongoing research across the network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in a era of global change

  16. Monitoring changes of tumor microenvironment in colorectal submucosa using multiphoton microscopy.

    Science.gov (United States)

    Qiu, Jingting; Jiang, Weizhong; Yang, Yinghong; Feng, Changyin; Chen, Zhifen; Guan, Guoxian; Zhuo, Shuangmu; Chen, Jianxin

    2015-01-01

    Recently, targeting tumor microenvironment has become a novel approach for cancer therapy. Collagen is one of important components of tissue microenvironment, and has been considered as a new visible target for cancer therapy. In this work, multiphoton microscopy (MPM) was used to monitor the changes of collagen in tumor microenvironment during tumor progression. It was found that MPM facilitates imaging of tumor cells and collagen. MPM images in different tumor microenvironment during tumor progression shows obvious increase in cell number and collagen degration. In addition, the quantitative analysis of collagen content and orientation index in tumor microenvironment shows significant alteration during tumor progression. These results suggest that MPM has the ability to monitor the changes of collagen morphology in tumor microenvironment and quantify content and orientation index of collagen during tumor progression. Therefore this technique is a powerful imaging tool for the investigation of targeting tumor microenvironment for cancer therapy. © Wiley Periodicals, Inc.

  17. Monitoring change in the abundance and distribution of insects using butterflies and other indicator groups.

    Science.gov (United States)

    Thomas, J A

    2005-02-28

    Conservative estimates suggest that 50-90% of the existing insect species on Earth have still to be discovered, yet the named insects alone comprise more than half of all known species of organism. With such poor baseline knowledge, monitoring change in insect diversity poses a formidable challenge to scientists and most attempts to generalize involve large extrapolations from a few well-studied taxa. Butterflies are often the only group for which accurate measures of change can be obtained. Four schemes, used successfully to assess change in British butterflies, that are increasingly being applied across the world are described: Red Data Books (RDB) list the best judgements of experts of the conservation status of species in their field of expertise; mapping schemes plot the changing distributions of species at scales of 1-100 km2; transect monitoring schemes generate time series of changes in abundance in sample populations of species on fixed sites across the UK; and occasional surveys measure the number, boundaries and size of all populations of a (usually RDB) species at intervals of 10-30 years. All schemes describe consistent patterns of change, but if they are to be more generally useful, it is important to understand how well butterflies are representative of other taxa. Comparisons with similarly measured changes in native bird and plant species suggest that butterflies have declined more rapidly that these other groups in Britain; it should soon be possible to test whether this pattern exists elsewhere. It is also demonstrated that extinction rates in British butterflies are similar to those in a range of other insect groups over 100 years once recording bias is accounted for, although probably lower than in aquatic or parasitic taxa. It is concluded that butterflies represent adequate indicators of change for many terrestrial insect groups, but recommended that similar schemes be extended to other popular groups, especially dragonflies, bumblebees

  18. Monitoring of Global Climate Change in the Earth from the Moon

    Science.gov (United States)

    Morozhenko, O. V.; Vidmachenko, A. P.; Nevedovskiy, P. V.; Choliy, V. Ya.

    2017-08-01

    The most important experimental data that should be obtained for the monitoring of global climate change of Earth are: investigations of the stratospheric aerosol layer, which affects the stratospheric ozone layer, effective and real equilibrium temperature of Earth, content of greenhouse gases. Scientific equipment should be installed on an automatic (better habitable) base on the surface of the Moon, on the polar, constantly visible from the Earth artificial satellite of the Moon or on a satellite located at the lunar point of Lagrange.

  19. Changing guards: time to move beyond Body Mass Index for population monitoring of excess adiposity

    OpenAIRE

    Tanamas, Stephanie K.; Lean, Michael E. J.; Combet, Emilie; Vlassopoulos, Antonios; Zimmet, Paul Z.; Peeters, Anna

    2016-01-01

    With the obesity epidemic, and the effects of aging populations, human phenotypes have changed over two generations, possibly more dramatically than in other species previously. As obesity is an important and growing hazard for population health, we recommend a systematic evaluation of the optimal measure(s) for population-level excess body fat. Ideal measure(s) for monitoring body composition and obesity should be simple, as accurate and sensitive as possible, and provide good categorisation...

  20. The association of income with health behavior change and disease monitoring among patients with chronic disease.

    Directory of Open Access Journals (Sweden)

    David J T Campbell

    Full Text Available BACKGROUND: Management of chronic diseases requires patients to adhere to recommended health behavior change and complete tests for monitoring. While studies have shown an association between low income and lack of adherence, the reasons why people with low income may be less likely to adhere are unclear. We sought to determine the association between household income and receipt of health behavior change advice, adherence to advice, receipt of recommended monitoring tests, and self-reported reasons for non-adherence/non-receipt. METHODS: We conducted a population-weighted survey, with 1849 respondents with cardiovascular-related chronic diseases (heart disease, hypertension, diabetes, stroke from Western Canada (n = 1849. We used log-binomial regression to examine the association between household income and the outcome variables of interest: receipt of advice for and adherence to health behavior change (sodium reduction, dietary improvement, increased physical activity, smoking cessation, weight loss, reasons for non-adherence, receipt of recommended monitoring tests (cholesterol, blood glucose, blood pressure, and reasons for non-receipt of tests. RESULTS: Behavior change advice was received equally by both low and high income respondents. Low income respondents were more likely than those with high income to not adhere to recommendations regarding smoking cessation (adjusted prevalence rate ratio (PRR: 1.55, 95%CI: 1.09-2.20, and more likely to not receive measurements of blood cholesterol (PRR: 1.72, 95%CI 1.24-2.40 or glucose (PRR: 1.80, 95%CI: 1.26-2.58. Those with low income were less likely to state that non-adherence/non-receipt was due to personal choice, and more likely to state that it was due to an extrinsic factor, such as cost or lack of accessibility. CONCLUSIONS: There are important income-related differences in the patterns of health behavior change and disease monitoring, as well as reasons for non-adherence or non

  1. Monitoring changes in the scattering properties of mouse skin with optical coherence tomography during an in vivo glucose tolerance test

    Science.gov (United States)

    Kinnunen, M.; Tausta, S.; Myllylä, R.; Vainio, S.

    2007-05-01

    A non-invasive glucose monitoring technique would make evaluation of blood glucose values easier and more convenient. This would help diabetic patients to control their blood glucose values more regularly. A few years ago optical coherence tomography (OCT) was proposed as a non-invasive sensor for monitoring changes in blood glucose concentration. The method is based on monitoring glucose-induced changes in the scattering properties of the target. This article describes how OCT was used to monitor changes in the scattering properties of mouse skin during an in vivo glucose tolerance test. The results show that OCT has the potential to register glucose-induced changes in the optical properties of the sample. However, a commercial OCT device with a probe designed for imaging is not very suitable for non-invasive monitoring of glucose-induced changes in scattering. The problems confronted in this study, possibly originating from the small size of the animals, are discussed in the article.

  2. Compensation for geometric changes during monitoring of 133Xe washout from subcutaneous adipose tissue

    DEFF Research Database (Denmark)

    Bülow, J; Madsen, J

    1975-01-01

    A method is described for automatic compensation of changes in geometry during monitoring of 133Xe-washout curves from subcutaneous depots. A 99mTc source is placed on the skin over the 133Xe depot, and both isotopes are counted simultaneously. Variations in the 99mTc activity (corrected for radi...... for radioactive decay) reflects changes in counting geometry and efficiency and are used for correction of the 133Xe elimination curve. The method permits accurate elimination curves to be obtained from subjects exercising on a bicycle ergometer or running a treadmill....

  3. Optical State-of-Change Monitor for Lead-Acid Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Jonathan D.

    1998-07-24

    A method and apparatus for determining the instantaneous state-of-charge of a battery in which change in composition with discharge manifests itself as a change in optical absorption. In a lead-acid battery, the sensor comprises a fiber optic system with an absorption cdl or, alternatively, an optical fiber woven into an absorbed-glass-mat battery. In a lithium-ion battery, the sensor comprises fiber optics for introducing light into the anode to monitor absorption when lithium ions are introduced.

  4. Response of the cytoplasmic and membrane proteome of Corynebacterium glutamicum ATCC 13032 to pH changes

    OpenAIRE

    Poetsch Ansgar; Barreiro Carlos; Schluesener Daniela; Barriuso-Iglesias Mónica; Martín Juan F

    2008-01-01

    Abstract Background C. glutamicum has traditionally been grown in neutral-pH media for amino acid production, but in a previous article we reported that this microorganism is a moderate alkaliphile since it grows optimally at pH 7.0–9.0, as shown in fermentor studies under tightly controlled pH conditions. We determined the best pH values to study differential expression of several genes after acidic or basic pH conditions (pH 6.0 for acidic expression and pH 9.0 for alkaline expression). Thu...

  5. Use of paravascular admittance waveforms to monitor relative change in arterial blood pressure

    Science.gov (United States)

    Zielinski, Todd M.; Hettrick, Doug; Cho, Yong

    2010-04-01

    Non-invasive methods to monitor ambulatory blood pressure often have limitations that can affect measurement accuracy and patient adherence [1]. Minimally invasive measurement of a relative blood pressure surrogate with an implantable device may provide a useful chronic diagnostic and monitoring tool. We assessed a technique that uses electrocardiogram and paravascular admittance waveform morphology analysis to one, measure a time duration (vascular tone index, VTI in milliseconds) change from the electrocardiogram R-wave to admittance waveform peak and two, measure the admittance waveform minimum, maximum and magnitude as indicators of change in arterial compliance/distensibility or pulse pressure secondary to change in afterload. Methods: Five anesthetized domestic pigs (32 ± 4.2 kg) were used to study the effects of phenylephrine (1-5 ug/kg/min) on femoral artery pressure and admittance waveform morphology measured with a quadrapolar electrode array catheter placed next to the femoral artery to assess the relative change in arterial compliance due to change in peripheral vascular tone. Results: Statistical difference was observed (p blood pressure may be suitable for implantable devices to detect progression of cardiovascular disease such as hypertension.

  6. North American Land Change Monitoring System: Current Status and Future Development

    Science.gov (United States)

    Pouliot, D.; Homer, C.; Ressl, R.; Takaki, F.; Meneses, C.; Latifovic, R.; Giri, C.; Colditz, R.; Jimenez, F.; Orozco, R.; Hossain, N.; Lopez, G.; Palafox, R.; Díaz, P.

    2009-05-01

    At the Land Cover Summit meeting held in Washington, DC in September 2006 the North American Land Change Monitoring System (NLCMS) project was initiated between representatives from the US Geological Survey (USGS), the National Institute of Geographic Statistics and Information of Mexico (INEGI) and the Canada Centre for Remote Sensing (CCRS). The objective of the NALCMS is a joint effort to create a harmonized system for multi-scale and multi-temporal monitoring and reporting of North American land cover change. The proposed system couples 250m and 30m resolutions, offering products relevant at both spatial scales. The two spatial resolutions will provide users with investigation, confirmation, calibration, and assessment of 250m change products with 30m product support. This combination of spatial resolutions offers a valuable increase in temporal frequency, context, and strategic prioritization for 30m products. In due course these land change products can provide continental, national, and regional consistency to land cover and land cover change analysis.

  7. Introduction to the European Monitoring and Evaluation Programme (EMEP and observed atmospheric composition change during 1972–2009

    Directory of Open Access Journals (Sweden)

    K. E. Yttri

    2012-06-01

    Full Text Available European scale harmonized monitoring of atmospheric composition was initiated in the early 1970s, and the activity has generated a comprehensive dataset (available at http://www.emep.int which allows the evaluation of regional and spatial trends of air pollution during a period of nearly 40 yr. Results from the monitoring made within EMEP, the European Monitoring and Evaluation Programme, show large reductions in ambient concentrations and deposition of sulphur species during the last decades. Reductions are in the order of 70–90% since the year 1980, and correspond well with reported emission changes. Also reduction in emissions of nitrogen oxides (NOx are reflected in the measurements, with an average decrease of nitrogen dioxide and nitrate in precipitation by about 23% and 25% respectively since 1990. Only minor reductions are however seen since the late 1990s. The concentrations of total nitrate in air have decreased on average only by 8% since 1990, and fewer sites show a significant trend. A majority of the EMEP sites show a decreasing trend in reduced nitrogen both in air and precipitation on the order of 25% since 1990. Deposition of base cations has decreased during the past 30 yr, and the pH in precipitation has increased across Europe. Large inter annual variations in the particulate matter mass concentrations reflect meteorological variability, but still there is a relatively clear overall decrease at several sites during the last decade. With few observations going back to the 1990s, the observed chemical composition is applied to document a change in particulate matter (PM mass even since 1980. These data indicate an overall reduction of about 5 μg m−3 from sulphate alone. Despite the significant reductions in sulphur emissions, sulphate still remains one of the single most important compounds contributing to regional scale aerosol mass concentration. Long-term ozone trends at EMEP sites show a mixed pattern. The year

  8. Enzyme-regulated the changes of pH values for assembling a colorimetric and multistage interconnection logic network with multiple readouts.

    Science.gov (United States)

    Huang, Yanyan; Ran, Xiang; Lin, Youhui; Ren, Jinsong; Qu, Xiaogang

    2015-04-22

    Based on enzymatic reactions-triggered changes of pH values and biocomputing, a novel and multistage interconnection biological network with multiple easy-detectable signal outputs has been developed. Compared with traditional chemical computing, the enzyme-based biological system could overcome the interference between reactions or the incompatibility of individual computing gates and offer a unique opportunity to assemble multicomponent/multifunctional logic circuitries. Our system included four enzyme inputs: β-galactosidase (β-gal), glucose oxidase (GOx), esterase (Est) and urease (Ur). With the assistance of two signal transducers (gold nanoparticles and acid-base indicators) or pH meter, the outputs of the biological network could be conveniently read by the naked eyes. In contrast to current methods, the approach present here could realize cost-effective, label-free and colorimetric logic operations without complicated instrument. By designing a series of Boolean logic operations, we could logically make judgment of the compositions of the samples on the basis of visual output signals. Our work offered a promising paradigm for future biological computing technology and might be highly useful in future intelligent diagnostics, prodrug activation, smart drug delivery, process control, and electronic applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Monitoring in microvascular surgery.

    Science.gov (United States)

    Furnas, H; Rosen, J M

    1991-03-01

    The importance of monitoring in microvascular surgery is underscored by the high reported salvage rates of failing free flaps and replants. In this overview, we begin by defining the physiology of ischemic tissue with emphasis given to the no-reflow phenomenon and the secondary critical ischemia times. Based on the physiological changes accompanying ischemia, several variables are defined that can be monitored to reflect the vascular state of a free flap or replant. Multifarious monitoring systems are then reviewed, including clinical observation, temperature, isotope clearance, ultrasonic Doppler, laser Doppler, transcutaneous oxygen tension, reflection plethysmography, dermofluorometry, pH, electromagnetic flowmetry, serial hematocrits, interstitial fluid pressure, and magnetic resonance imaging.

  10. Satellite gravity measurement monitoring terrestrial water storage change and drought in the continental United States

    Science.gov (United States)

    Yi, Hang; Wen, Lianxing

    2016-01-01

    We use satellite gravity measurements in the Gravity Recovery and Climate Experiment (GRACE) to estimate terrestrial water storage (TWS) change in the continental United States (US) from 2003 to 2012, and establish a GRACE-based Hydrological Drought Index (GHDI) for drought monitoring. GRACE-inferred TWS exhibits opposite patterns between north and south of the continental US from 2003 to 2012, with the equivalent water thickness increasing from -4.0 to 9.4 cm in the north and decreasing from 4.1 to -6.7 cm in the south. The equivalent water thickness also decreases by -5.1 cm in the middle south in 2006. GHDI is established to represent the extent of GRACE-inferred TWS anomaly departing from its historical average and is calibrated to resemble traditional Palmer Hydrological Drought Index (PHDI) in the continental US. GHDI exhibits good correlations with PHDI in the continental US, indicating its feasibility for drought monitoring. Since GHDI is GRACE-based and has minimal dependence of hydrological parameters on the ground, it can be extended for global drought monitoring, particularly useful for the countries that lack sufficient hydrological monitoring infrastructures on the ground.

  11. Introduction to the European Monitoring and Evaluation Programme (EMEP and observed atmospheric composition change during 1972–2009

    Directory of Open Access Journals (Sweden)

    K. E. Yttri

    2012-01-01

    Full Text Available European scale harmonized monitoring of atmospheric composition was initiated in the early 1970ies, and the activity has generated a comprehensive dataset which allows to evaluate regional and spatial trends of air pollution during a period of nearly 40 yr. Results from the monitoring made within EMEP, the European Monitoring and Evaluation Programme, show large reductions in ambient concentrations and deposition of sulphur species during the last decades. Reductions are in the order of 70–90% since the year 1980, and correspond well with reported emission changes. Also reduction in emissions of nitrogen oxides (NOx are reflected in the measurements, with an average decrease of nitrogen dioxide and nitrate in precipitation by about 23% and 25% respectively since 1990. Only minor reductions are however seen since the late 1990ies. The concentrations of total nitrate in air have decreased on average only by 8% since 1990, and fewer sites show a significant trend. A majority of the EMEP sites show a decreasing trend in reduced nitrogen both in air and precipitation on the order of 25%. Deposition of base cations has decreased during the past 30 yr, and the pH in precipitation has increased across Europe. Large interannual variations in the particulate matter mass concentrations reflect meteorological variability, but still there is a relatively clear overall decrease at several sites during the last decade. With few observations going back to the 1990ies, the observed chemical composition is applied to document a change in particulate matter (PM mass even since 1980. These data indicate an overall reduction of about 5 μg m−3 from sulphate alone. Long-term ozone trends at EMEP sites show a mixed pattern. The year-to-year variability in ozone due to varying meteorology is substantial, making it hard to separate the trends caused by reduced emissions from other effects. For the Nordic countries the data indicate a slight reduction in the number

  12. Amine-free reversible hydrogen storage in formate salts catalyzed by ruthenium pincer complex without pH control or solvent change.

    Science.gov (United States)

    Kothandaraman, Jotheeswari; Czaun, Miklos; Goeppert, Alain; Haiges, Ralf; Jones, John-Paul; May, Robert B; Prakash, G K Surya; Olah, George A

    2015-04-24

    Due to the intermittent nature of most renewable energy sources, such as solar and wind, energy storage is increasingly required. Since electricity is difficult to store, hydrogen obtained by electrochemical water splitting has been proposed as an energy carrier. However, the handling and transportation of hydrogen in large quantities is in itself a challenge. We therefore present here a method for hydrogen storage based on a CO2 (HCO3 (-) )/H2 and formate equilibrium. This amine-free and efficient reversible system (>90 % yield in both directions) is catalyzed by well-defined and commercially available Ru pincer complexes. The formate dehydrogenation was triggered by simple pressure swing without requiring external pH control or the change of either the solvent or the catalyst. Up to six hydrogenation-dehydrogenation cycles were performed and the catalyst performance remained steady with high selectivity (CO free H2 /CO2 mixture was produced).

  13. Direct monitoring changes of salbutamol concentration in serum by chemiluminescent imaging.

    Science.gov (United States)

    Zhang, Canli; Zhang, Ruichao; Na, Na; Delanghe, Joris R; Ouyang, Jin

    2011-07-15

    We report in this manuscript, the use of direct ammonium persulfate-enhanced chemiluminescence (CL) imaging, to monitor changes to measure serum salbutamol concentration in subjects of different haptoglobin (Hp) phenotypes at different dosing time. It was noted that CL generated from Hp was decreased due to salbutamol's reducibility, which was used for monitoring salbutamol concentration in serum. The serum from the subjects treated by oral administration of salbutamol, was collected at different dosing time and was separated by polyacrylamide gel electrophoresis (PAGE) prior to the CL detection. According to CL images, samples were separated into three groups based on the Hp phenotypes. The curves of CL signal intensity versus time were obtained for each group, and we demonstrated that there were more significant variables on binding ability between groups. The maximum salbutamol concentration in the serum appeared after 4h, which was in agreement with the literature. In addition, the binding constants of salbutamol to Hp were determined by a fluorescence-based method, whose results were in agreement with the phenomenon of the greater salbutamol metabolism rate for Group Hp 1-1 than Group Hp 2-2. The presented method can monitor changes of salbutamol concentration in serum directly, making the procedures much simple, convenient, rapid and has the property of lower cost. It provided us with excellent reference information for the individual dosage regimen of different Hp groups, which hopefully could become a potential method for further pharmaceutical research.

  14. Monitoring and managing responses to climate change at the retreating range edge of forest trees.

    Science.gov (United States)

    Jump, Alistair S; Cavin, Liam; Hunter, Peter D

    2010-10-06

    Rising temperatures and increasing drought severity linked to global climate change are negatively impacting forest growth and function at the equatorial range edge of species distributions. Rapid dieback and range retractions are predicted to occur in many areas as temperatures continue to rise. Despite widespread negative impacts at the ecosystem level, equatorial range edges are not well studied, and their responses to climate change are poorly understood. Effective monitoring of tree responses to climate in these regions is of critical importance in order to predict and manage threats to populations. Remote sensing of impacts on forests can be combined with ground-based assessment of environmental and ecological changes to identify populations most at risk. Modelling may be useful as a 'first-filter' to identify populations of concern but, together with many remote sensing methods, often lacks adequate resolution for application at the range edge. A multidisciplinary approach, combining remote observation with targeted ground-based monitoring of local susceptible and resistant populations, is therefore required. Once at-risk regions have been identified, management can be adapted to reduce immediate risks in priority populations, and promote long-term adaptation to change. However, management to protect forest ecosystem function may be preferable where the maintenance of historical species assemblages is no longer viable.

  15. Complexities and opportunities in monitoring and evaluating US and global changes by the food industry.

    Science.gov (United States)

    Ng, S W; Dunford, E

    2013-11-01

    In developed nations and increasingly in the rest of the world, a large proportion of people's diets comes from manufactured food sources and food not produced at home. These types of products are constantly changing and have significant nutrition and health implications for the world's population. However, researchers, public health workers and policy makers face major complexities in understanding what these changes are and their relationships to diet and health outcomes. This paper will describe some of the complexities faced in monitoring and evaluating the nutritional composition of food products and what it means for population health. Importantly, no existing food composition database is able to keep up with the continuous reformulation and introductions and removals of packaged foods and food services. The paper will also discuss opportunities to improve and update the monitoring and evaluation of changes made by each of these key sectors of the modern food supply and how these changes can influence the nutrients purchased or consumed across the globe. The focus will be on the United States with some examples from other developed nations and a discussion of implications for low- and middle-income countries.

  16. Wetland Monitoring Using the Curvelet-Based Change Detection Method on Polarimetric SAR Imagery

    Directory of Open Access Journals (Sweden)

    Andreas Schmitt

    2013-07-01

    Full Text Available One fundamental task in wetland monitoring is the regular mapping of (temporarily flooded areas especially beneath vegetation. Due to the independence of weather and illumination conditions, Synthetic Aperture Radar (SAR sensors could provide a suitable data base. Using polarimetric modes enables the identification of flooded vegetation by means of the typical double-bounce scattering. In this paper three decomposition techniques—Cloude-Pottier, Freeman-Durden, and Normalized Kennaugh elements—are compared to each other in terms of identifying the flooding extent as well as its temporal change. The image comparison along the time series is performed with the help of the Curvelet-based Change Detection Method. The results indicate that the decomposition algorithm has a strong impact on the robustness and reliability of the change detection. The Normalized Kennaugh elements turn out to be the optimal representation for Curvelet-based change detection processing. Furthermore, the co-polarized channels (same transmit and receive polarization in horizontal (HH and vertical (VV direction respectively appear to be sufficient for wetland monitoring so that dual-co-polarized imaging modes could be an alternative to conventional quad-polarized acquisitions.

  17. Dosage Effects of Salt and pH Stresses on Saccharomyces cerevisiae as Monitored via Metabolites by Using Two Dimensional NMR Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Chae, Young Kee; Kim, Seol Hyun [Sejong Univ., Seoul (Korea, Republic of); Ellinger, James E.; Markley, John L. [Univ. of Wisconsin-Madison Madison (United States)

    2013-12-15

    Saccharomyces cerevisiae, which is a common species of yeast, is by far the most extensively studied model of a eukaryote because although it is one of the simplest eukaryotes, its basic cellular processes resemble those of higher organisms. In addition, yeast is a commercially valuable organism for ethanol production. Since the yeast data can be extrapolated to the important aspects of higher organisms, many researchers have studied yeast metabolism under various conditions. In this report, we analyzed and compared metabolites of Saccharomyces cerevisiae under salt and pH stresses of various strengths by using two-dimensional NMR spectroscopy. A total of 31 metabolites were identified for most of the samples. The levels of many identified metabolites showed gradual or drastic increases or decreases depending on the severity of the stresses involved. The statistical analysis produced a holistic outline: pH stresses were clustered together, but salt stresses were spread out depending on the severity. This work could provide a link between the metabolite profiles and mRNA or protein profiles under representative and well studied stress conditions.

  18. Induction of intracellular Ca2+ and pH changes in Sf9 insect cells by rhodojaponin-III, a natural botanic insecticide isolated from Rhododendron molle.

    Science.gov (United States)

    Cheng, Xing-An; Xie, Jian-Jun; Hu, Mei-Ying; Zhang, Yan-Bo; Huang, Jing-Fei

    2011-04-15

    Many studies on intracellular calcium ([Ca2+](i)) and intracellular pH (pH(i)) have been carried out due to their importance in regulation of different cellular functions. However, most of the previous studies are focused on human or mammalian cells. The purpose of the present study was to characterize the effect of Rhodojaponin-III (R-III) on [Ca2+](i) and pH(i) and the proliferation of Sf9 cells. R-III strongly inhibited Sf9 cells proliferation with a time- and dose-dependent manner. Flow cytometry established that R-III interfered with Sf9 cells division and arrested them in G2/M. By using confocal scanning technique, effects of R-III on intracellular free calcium ([Ca2+](i)) and intracellular pH (pH(i)) in Sf9 cells were determined. R-III induced a significant dose-dependent (1, 10, 100, 200 μg/mL) increase in [Ca2+](i) and pH(i) of Sf9 cells in presence of Ca2+-containing solution (Hanks) and an irreversible decrease in the absence of extra cellular Ca2+. We also found that both extra cellular Ca2+ and intracellular Ca2+ stores contributed to the increase of [Ca2+](i), because completely treating Sf9 cells with CdCl(2) (5 mM), a Ca2+ channels blocker, R-III (100 μg/mL) induced a transient elevation of [Ca2+](i) in case of cells either in presence of Ca2+ containing or Ca2+ free solution. In these conditions, pH(i) showed similar changes with that of [Ca2+](i) on the whole. Accordingly, we supposed that there was a certain linkage for change of [Ca2+](i), cell cycle arrest, proliferation inhibition in Sf9 cells induced by R-III.

  19. Induction of Intracellular Ca2+ and pH Changes in Sf9 Insect Cells by Rhodojaponin-III, A Natural Botanic Insecticide Isolated from Rhododendron molle

    Directory of Open Access Journals (Sweden)

    Yan-Bo Zhang

    2011-04-01

    Full Text Available Many studies on intracellular calcium ([Ca2+]i and intracellular pH (pHi have been carried out due to their importance in regulation of different cellular functions. However, most of the previous studies are focused on human or mammalian cells. The purpose of the present study was to characterize the effect of Rhodojaponin-III (R-III on [Ca2+]i and pHi and the proliferation of Sf9 cells. R-III strongly inhibited Sf9 cells proliferation with a time- and dose-dependent manner. Flow cytometry established that R-III interfered with Sf9 cells division and arrested them in G2/M. By using confocal scanning technique, effects of R-III on intracellular free calcium ([Ca2+]i and intracellular pH (pHi in Sf9 cells were determined. R-III induced a significant dose-dependent (1, 10, 100, 200 μg/mL increase in [Ca2+]i and pHi of Sf9 cells in presence of Ca2+-containing solution (Hanks and an irreversible decrease in the absence of extra cellular Ca2+. We also found that both extra cellular Ca2+ and intracellular Ca2+ stores contributed to the increase of [Ca2+]i, because completely treating Sf9 cells with CdCl2 (5 mM, a Ca2+ channels blocker, R-III (100 μg/mL induced a transient elevation of [Ca2+]i in case of cells either in presence of Ca2+ containing or Ca2+ free solution. In these conditions, pHi showed similar changes with that of [Ca2+]i on the whole. Accordingly, we supposed that there was a certain linkage for change of [Ca2+]i, cell cycle arrest, proliferation inhibition in Sf9 cells induced by R-III.

  20. In vivo measurement of intracellular pH in human brain during different tensions of carbon dioxide in arterial blood. A 31P-NMR study

    DEFF Research Database (Denmark)

    Jensen, K E; Thomsen, C; Henriksen, O

    1988-01-01

    The effect of changes in carbon dioxide tension in arterial blood upon intracellular pH in brain tissue was studied in seven healthy volunteers, aged 22-45 years. The pH changes were monitored by use of 31P nuclear magnetic resonance spectroscopy, performed on a whole-body 1.5 Tesla Siemens imaging...

  1. The Key to Individualized Addiction Treatment is Comprehensive Assessment and Monitoring of Symptoms and Behavioral Change

    Directory of Open Access Journals (Sweden)

    Thomas F. Hilton

    2015-10-01

    Full Text Available Modern health services now strive for individualized treatment. This approach has been enabled by the increase in knowledge derived from neuroscience and genomics. Substance use disorders are no exception to individualized treatment even though there are no gene-specific medications yet available. What is available is the ability to quickly and precisely assess and monitor biopsychosocial variables known to vary during addiction recovery and which place addicts at increased risk of relapse. Monitoring a broad spectrum of biopsychosocial health enables providers to address diverse genome-specific changes that might trigger withdrawal from treatment or recovery relapse in time to prevent that from occurring. This paper describes modern measurement tools contained in the NIH Patient-Reported Outcomes Measurement Information System (PROMIS and the NIH Toolbox and suggests how they might be applied to support recovery from alcohol and other substance use disorders in both pharmacological and abstinence-oriented modalities of care.

  2. Monitoring of small and medium embankment dams on permafrost in a changing climate

    Institute of Scientific and Technical Information of China (English)

    Rudolf V.Zhang

    2014-01-01

    Global climate warming which began in the second half of the twentieth century is continuing. It is associated with in creased risks for ecological management, especially in permafrost areas comprising over 65% of Russia. Of special con cern are dams constructed on permafrost. They are subject not only to climatic impacts, but also to additional hydrothermal loads from water reservoirs. This paper presents the concept of geocryological monitoring of dams and other water re source projects and substantiates its necessity in view of climatic change. It also presents methods, scope and implemen tation of geocryological monitoring at medium and small dams, considering the specific nature of Far Northern areas, as well as the complicated geotechnical, hydrogeological and permafrost conditions.

  3. The Key to Individualized Addiction Treatment is Comprehensive Assessment and Monitoring of Symptoms and Behavioral Change.

    Science.gov (United States)

    Hilton, Thomas F; Pilkonis, Paul A

    2015-10-30

    Modern health services now strive for individualized treatment. This approach has been enabled by the increase in knowledge derived from neuroscience and genomics. Substance use disorders are no exception to individualized treatment even though there are no gene-specific medications yet available. What is available is the ability to quickly and precisely assess and monitor biopsychosocial variables known to vary during addiction recovery and which place addicts at increased risk of relapse. Monitoring a broad spectrum of biopsychosocial health enables providers to address diverse genome-specific changes that might trigger withdrawal from treatment or recovery relapse in time to prevent that from occurring. This paper describes modern measurement tools contained in the NIH Patient-Reported Outcomes Measurement Information System (PROMIS) and the NIH Toolbox and suggests how they might be applied to support recovery from alcohol and other substance use disorders in both pharmacological and abstinence-oriented modalities of care.

  4. Monitoring subsidence with InSAR and inference of groundwater change

    Science.gov (United States)

    Farr, T. G.

    2014-12-01

    Groundwater use is increasing in many parts of the world due to population pressure and reduced availability of surface water and rainfall. California's Central Valley and southern Arizona in particular have experienced subsidence in many groundwater basins in recent years due to groundwater overdraft. In order to make informed decisions for adaptation, water resource managers need to know the extent of groundwater depletion, both spatially and volumetrically, and to be able to monitor it over long periods. Water wells provide one solution, but owing to remoteness, funding limitations, a lack of wells, and the difficulty of mandating government monitoring of private wells, less direct methods are necessary. Mapping and monitoring subsidence and rebound from orbit with interferometric synthetic aperture radar (InSAR) may provide important indicators of groundwater state and dynamics for water resource managers as well as warnings of potential damage to infrastructure. We are working with water resource managers at the California Department of Water Resources to produce and update maps of subsidence 'hot-spots' where subsidence threatens to cause irreversible aquifer compaction and loss of groundwater storage capacity. In the future, Germany's TerraSAR-X, Italy's Cosmo SkyMed, Japan's PALSAR-2, Europe's Sentinels, and NASA's NISAR offer the promise of extending the time series of observations and expanding this capability to regions of the world with no effective means to monitor the state of their groundwater. This would provide societal benefits to large segments of the global population dependent on groundwater to bridge gaps in surface and rain water supply. As Earth's climate changes, monitoring of this critical resource will help reduce conflicts over water. * Work performed under contract to NASA

  5. Monitoring changes of optical attenuation coefficients of acupuncture points during laser acupuncture by optical coherence tomography

    Science.gov (United States)

    Huang, Yimei; Yang, Hongqin; Wang, Yuhua; Zheng, Liqin; Xie, Shusen

    2010-11-01

    The physical properties of acupuncture point were important to discover the mechanism of acupuncture meridian. In this paper, we used an optical coherence tomography to monitor in vivo the changes of optical attenuation coefficients of Hegu acupuncture point and non-acupuncture point during laser irradiation on Yangxi acupuncture point. The optical attenuation coefficients of Hegu acupuncture point and non-acupuncture point were obtained by fitting the raw data according to the Beer-Lambert's law. The experimental results showed that the optical attenuation coefficient of Hegu acupuncture point decreased during the laser acupuncture, in contrast to a barely changed result in that of non-acupuncture point. The significant change of optical attenuation coefficient of Hegu acupuncture point indicated that there was a correlation between Hegu and Yangxi acupuncture points to some extent.

  6. Programmable pH buffers

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Dara Van; Huber, Dale L.; Bunker, Bruce C.; Roberts, Mark E.

    2017-01-24

    A programmable pH buffer comprises a copolymer that changes pK.sub.a at a lower critical solution temperature (LCST) in water. The copolymer comprises a thermally programmable polymer that undergoes a hydrophobic-to-hydrophilic phase change at the LCST and an electrolytic polymer that exhibits acid-base properties that are responsive to the phase change. The programmable pH buffer can be used to sequester CO.sub.2 into water.

  7. Monitoring and change detection of Wadden Sea areas using Lidar data

    Science.gov (United States)

    Schmidt, A.; Soergel, U.

    2013-10-01

    In coastal areas morphological changes of various kinds are caused by tidal flows, storms, climate change, and human activities. For these reasons a recurrent monitoring becomes necessary in order to detect undesired changes at early stages enabling rapid countermeasures to mitigate or minimize potential harm or hazard. The morphology of the terrain can be represented by highly precise digital terrain models (DTM). Airborne lidar (light detection and ranging) has become a standard method for DTM generation in coastal zones like Wadden Sea areas. In comparison to echo sounding systems, lidar is feasible for data acquisition of large areas. However, only the eulittoral zone can be covered by standard laser because the near-infrared laser pulses are not able to penetrate water which remains, for example, in some tidal channels even during low tide. In the framework of a German research project, we analyse the spatial and temporal variability of Wadden Sea areas in the North Sea. For a systematic monitoring and the detection of morphological changes we compare terrain models of two different epochs in order to determine height differences which can be caused by natural influences or human activities. We focus especially on the analysis of morphological changes near to tidal channels. In order to detect changes we compare the location of edges derived from each DTM based on the gray values' gradients. Our results for a test site in the German Wadden Sea show height differences up to 1 m due to the shifting of tidal channels and relocations of the channels up to 55 m within a period of two years.

  8. Improvement of chemical monitoring of water-chemistry conditions at thermal power stations based on electric conductivity and pH measurements

    Science.gov (United States)

    Larin, A. B.; Larin, B. M.

    2016-05-01

    The increased requirements to the quality of the water heat conductor for working superhigh (SHP) and supercritical (SCP) pressure power plants and promising units, including combined-cycle gas turbine (CCGT) units and power plants with ultrasupercritical parameters (USCPs), can largely be satisfied through specific electric conductivity and pH measurements for cooled heat conductor samples combined with calculations of ionic equilibria and indirect measurements of several specified and diagnostic parameters. The possibility of calculating the ammonia and chloride concentrations and the total concentration of hardness and sodium cations in the feed water of drum-type boilers and the phosphate and salt contents in boiler water was demonstrated. An equation for evaluating the content of potentially acid substances in the feed water of monotube boilers was suggested. The potential of the developed procedure for evaluating the state of waterchemistry conditions (WCCs) in power plants with CCGT units was shown.

  9. Response of Listeria monocytogenes to disinfection stress at the single-cell and population levels as monitored by intracellular pH measurements and viable-cell counts

    DEFF Research Database (Denmark)

    Kastbjerg, Vicky Gaedt; Nielsen, Dennis S.; Arneborg, Nils;

    2009-01-01

    of the bacterium. In situ analyses of Listeria monocytogenes single cells were performed during exposure to different concentrations of the disinfectant Incimaxx DES to study a possible population subdivision. Bacterial survival was quantified with plate counting and disinfection stress at the single-cell level...... by measuring intracellular pH (pHi) over time by fluorescence ratio imaging microscopy. pHi values were initially 7 to 7.5 and decreased in both attached and planktonic L. monocytogenes cells during exposure to sublethal and lethal concentrations of Incimaxx DES. The response of the bacterial population...... that a population of L. monocytogenes cells, whether planktonic or attached, is homogenous with respect to sensitivity to an acidic disinfectant studied on the single-cell level. Hence a major subpopulation more tolerant to disinfectants, and hence more persistent, does not appear to be present....

  10. Inferential monitoring of global change impact on biodiversity through remote sensing and species distribution modeling

    Science.gov (United States)

    Sangermano, Florencia

    2009-12-01

    The world is suffering from rapid changes in both climate and land cover which are the main factors affecting global biodiversity. These changes may affect ecosystems by altering species distributions, population sizes, and community compositions, which emphasizes the need for a rapid assessment of biodiversity status for conservation and management purposes. Current approaches on monitoring biodiversity rely mainly on long term observations of predetermined sites, which require large amounts of time, money and personnel to be executed. In order to overcome problems associated with current field monitoring methods, the main objective of this dissertation is the development of framework for inferential monitoring of the impact of global change on biodiversity based on remotely sensed data coupled with species distribution modeling techniques. Several research pieces were performed independently in order to fulfill this goal. First, species distribution modeling was used to identify the ranges of 6362 birds, mammals and amphibians in South America. Chapter 1 compares the power of different presence-only species distribution methods for modeling distributions of species with different response curves to environmental gradients and sample sizes. It was found that there is large variability in the power of the methods for modeling habitat suitability and species ranges, showing the importance of performing, when possible, a preliminary gradient analysis of the species distribution before selecting the method to be used. Chapter 2 presents a new methodology for the redefinition of species range polygons. Using a method capable of establishing the uncertainty in the definition of existing range polygons, the automated procedure identifies the relative importance of bioclimatic variables for the species, predicts their ranges and generates a quality assessment report to explore prediction errors. Analysis using independent validation data shows the power of this

  11. Long-term monitoring of change in Tropical grasslands- GLORIA network in the Andes

    Science.gov (United States)

    Cuesta, F. X.; Muriel, P.; Halloy, S.; Beck, S.; Meneses, R. I.; Irazabal, J.; Aguirre, N.; Viñas, P.; Suarez, D.; Becerra, M. T.; Gloria-Andes Network

    2013-05-01

    It has been shown that predicted warming and increased frequency of extreme weather events increase with altitude in the Andean mountains. Combined with enormous topographic (and hence precipitation) heterogeneity, poverty and intensive land use, creates in the region a situation of high vulnerability to global change. Since 2005 the network Global Research Initiative in Alpine Environment (GLORIA) sites have been progressively installed in Andean countries to monitor changes, document the type and magnitude of impacts and provide guidance to develop adaptation strategies for biodiversity, humans, and productive systems. We report the preliminary results from 10 of those sites, in addition to new sites planned in South America. These sites provide baseline data and identify processes and patterns in plant biodiversity across different geographic contexts. These preliminary results show the tremendous singularity of the vegetation and flora patterns in the study sites, suggesting high sensitivity of these ecosystems to climate anomalies. It is expected that the consolidation of this network will support and strengthen long-term observation and monitoring research programs to enable the documentation and understanding of climate change impacts on the Andean biota. Our research considers complementary modules of investigation (e.g. carbon stocks and fluxes, plant responses to experimental manipulation) that contextualize the challenges and opportunities of adaptation for biodiversity and socio-economic components, providing measures of trends as well as effectiveness of adaptive management strategies.

  12. Applying Uav and Photogrammetry to Monitor the Morphological Changes Along the Beach in Penghu Islands

    Science.gov (United States)

    Lu, Cheng-Hao

    2016-06-01

    Penghu islands, in the southern Taiwan Strait, is a remnant of a middle-late Miocene basaltic shield volcano. We present a procedure to use UAV (Unmanned Aerial Vehicles) to perform photogrammetry survey and monitoring analysis in beach evolution scenarios. The aim of this study is to understand spatial-temporal change along the sandy beach in Penghu islands, especially as for the effects of typhoon and coastal structures. According to the study result, this example of application is provided to show the results and the potential of this methodology in real beach changes. In addition, we found the typhoon and coastal structures play important roles to shape the beach morphology and its evolution. The result of beach monitoring reveals that the reduction and change of sand volume in Shanshui beach resulted from the placement of detached breakwater complexes. This coastal structure likely resulted in the development of tombolo and therefor make the beach unstable and subject to conduct rip current and more erosion.

  13. Challenges in monitoring and managing engineered slopes in a changing climate

    Directory of Open Access Journals (Sweden)

    Hughes Paul N

    2016-01-01

    Full Text Available Geotechnical asset owners need to know which parts of their asset network are vulnerable to climate change induced failure in order to optimise future investment. Protecting these vulnerable slopes requires monitoring systems capable of identifying and alerting to asset operators changes in the internal conditions that precede failure. Current monitoring systems are heavily reliant on point sensors which can be difficult to interpret across slope scale. This paper presents challenges to producing such a system and research being carried out to address some of these using electrical resistance tomography (ERT. Experimental results show that whilst it is possible to measure soil water content indirectly via resistivity the relationship between resistivity and water content will change over time for a given slope. If geotechnical parameters such as pore water pressure are to be estimated using this method then ERT systems will require integrating with more conventional geotechnical instrumentation to ensure correct representative information is provided. The paper also presents examples of how such data can be processed and communicated to asset owners for the purposes of asset management.

  14. Conformational Changes of Calmodulin on Calcium and Peptide Binding Monitored by Film Bulk Acoustic Resonators

    Directory of Open Access Journals (Sweden)

    Janos Vörös

    2011-12-01

    Full Text Available Film bulk acoustic resonators (FBAR are mass sensitive, label-free biosensors that allow monitoring of the interaction between biomolecules. In this paper we use the FBAR to measure the binding of calcium and the CaMKII peptide to calmodulin. Because the mass of the calcium is too small to be detected, the conformational change caused by the binding process is measured by monitoring the resonant frequency and the motional resistance of the FBAR. The resonant frequency is a measure for the amount of mass coupled to the sensor while the motional resistance is influenced by the viscoelastic properties of the adsorbent. The measured frequency shift during the calcium adsorptions was found to be strongly dependent on the surface concentration of the immobilized calmodulin, which indicates that the measured signal is significantly influenced by the amount of water inside the calmodulin layer. By plotting the measured motional resistance against the frequency shift, a mass adsorption can be distinguished from processes involving measurable conformational changes. With this method three serial processes were identified during the peptide binding. The results show that the FBAR is a promising technology for the label-free measurement of conformational changes.

  15. Studying the drift of in line pH measurements in cell culture.

    Science.gov (United States)

    Saucedo, V; Wolk, B; Arroyo, A; Feng, C D

    2011-01-01

    The culture of Chinese hamster ovary (CHO) cells to produce monoclonal antibodies (MAb) requires accurate measurement and control of pH. Unwanted pH drifts in cell culture can adversely affect process performance, product quality, and product yield. To measure and control pH throughout the length of a culture, most cell culture processes use traditional glass pH probes. Several variables can affect the design and performance of glass pH electrodes and lead to drift in the measurement. Understanding these variables and their effects on pH performance can lead to design improvements and potentially reduce the drift. In this study, a set of Rosemount Analytical glass pH probes was investigated in cell culture operations. Electrochemical properties of the probes were monitored throughout the experiments. Experimental results show that the glass membrane potential experiences the biggest change during cell culture operations. Changes in the reference electrode potential are small compared with the changes in glass membrane potential. The glass membranes are affected by the steam sterilization process and this is the main cause for drift in the probe sensing signal during cell culture operations. Steam sterilization can cause the potential of glass membranes to change by up to 15 mV (∼ 0.25 pH units). This change in membrane potential can be observed as an undesirable pH drift in bioreactors. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  16. Strain Observation Affected by Groundwater-Level Change in Seismic Precursor Monitoring

    Science.gov (United States)

    Zhang, Lei; Cao, Daiyong; Zhang, Jingfa

    2017-03-01

    Groundwater extraction is one of the most typical disturbance factors for strain observation in seismic precursor monitoring. The statistic regression method is used to study based on the relation between the variation of strain and the groundwater level. The least square regression linear model is built between the annual variation of Sangzi groundwater level and the Xiaoxinzhuang strain data. Such model meets t test with significance level α = 0. 0 5, which confirms that groundwater-level change in each year affects strain measurement significantly and strain's trend variation is related to groundwater-level change. Consequently, a new correction method about strain data is put forward based on the groundwater-level annual variation to eliminate the trend change. Results indicate that the accumulated residual deformation causes the horizontal displacement and strain change, which is on account of that the amount of groundwater recharge is less than that of extraction around Xiaoxinzhuang cave, the phreatic surface continues to descend, and residual deformation accumulates and leads to local subsidence area. Therefore, the decline trend change of strain is related to groundwater-level change and is not seismic precursor.

  17. Advancing drought monitoring using a Small Unmanned Aerial System (sUAS) in a changing climate

    Science.gov (United States)

    Ryu, J.

    2016-12-01

    Drought as a natural hazard, increasingly threatens the sustainability of regional water resources around the world. Given current trends in climate variability and change, droughts are likely to continue and increase. One of the effective ways to mitigate drought impacts may be to use a Small Unmanned Aerial System (sUAS) to improve understanding of the factors that drive the onset and development of drought conditions at local levels would enable planners and end users to more effectively manage and meter out limited water resources. During the presentation, the author will propose a methodological approach to apply sUAS for drought monitoring along with federal regulations and policies.

  18. Introduction to the Special Issue: Geospatial Monitoring and Modeling of Environmental Change

    Directory of Open Access Journals (Sweden)

    Duccio Rocchini

    2014-02-01

    Full Text Available Geospatial modeling is an approach to apply analysis to monitor environmental change over time considering different fields of re-search, including computer science, remote sensing, ecology, environmental science, life science, geography (see [1,2] for a critique. The special issue was instigated to publish straightforward research on the matter in order to stimulate further discussion on the potential of geospatial modelling. Both theoretical and empirical papers are part of the issue with the support of the International Society for Photogrammetry and Remote Sensing, promoting an advanced forum for the science and technology of geographic information.

  19. Using Pneumococcal Carriage Data to Monitor Postvaccination Changes in the Incidence of Pneumococcal Otitis Media.

    Science.gov (United States)

    Flasche, Stefan; Givon-Lavi, Noga; Dagan, Ron

    2016-11-01

    Pneumococcal conjugate vaccines (PCVs) have substantially reduced the burden of pneumococcal disease, including the incidence of otitis media (OM). However, in most countries, no surveillance exists to monitor the change in pneumococcal OM incidence after the introduction of PCVs. We explored whether measuring pneumococcal carriage was a useful surrogate for monitoring postvaccination changes in the incidence of pneumococcal OM. The 7-valent PCV was introduced to Israel's national immunization program in July 2009 and gradually replaced by the 13-valent PCV starting in November 2010. Each day since 2009, nasopharyngeal swabs have been obtained from the first 4 Bedouin children and the first 4 Jewish children who were younger than 5 years old and attended a pediatric emergency room in southern Israel. During the same time, OM surveillance in southern Israel included all children younger than 2 years of age who were diagnosed with OM and had undergone a middle-ear fluid culture. The relative change in the prevalence of vaccine-serotype (VT) pneumococcal carriage was predictive of the relative change in incidence of OM due to VT pneumococcus. However, the serotype replacement observed in non-VT carriage is not paralleled in the incidence of OM due to non-VT pneumococcus. This could indicate that there are more complex mechanisms of the immune response involved in preventing initial and consecutive episodes of OM, which has been changed through declining prevalence of the most virulent serotypes as a result of vaccination. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Monitoring the coastline change of Hatiya Island in Bangladesh using remote sensing techniques

    Science.gov (United States)

    Ghosh, Manoj Kumer; Kumar, Lalit; Roy, Chandan

    2015-03-01

    A large percentage of the world's population is concentrated along the coastal zones. These environmentally sensitive areas are under intense pressure from natural processes such as erosion, accretion and natural disasters as well as anthropogenic processes such as urban growth, resource development and pollution. These threats have made the coastal zone a priority for coastline monitoring programs and sustainable coastal management. This research utilizes integrated techniques of remote sensing and geographic information system (GIS) to monitor coastline changes from 1989 to 2010 at Hatiya Island, Bangladesh. In this study, satellite images from Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM) were used to quantify the spatio-temporal changes that took place in the coastal zone of Hatiya Island during the specified period. The modified normalized difference water index (MNDWI) algorithm was applied to TM (1989 and 2010) and ETM (2000) images to discriminate the land-water interface and the on-screen digitizing approach was used over the MNDWI images of 1989, 2000 and 2010 for coastline extraction. Afterwards, the extent of changes in the coastline was estimated through overlaying the digitized maps of Hatiya Island of all three years. Coastline positions were highlighted to infer the erosion/accretion sectors along the coast, and the coastline changes were calculated. The results showed that erosion was severe in the northern and western parts of the island, whereas the southern and eastern parts of the island gained land through sedimentation. Over the study period (1989-2010), this offshore island witnessed the erosion of 6476 hectares. In contrast it experienced an accretion of 9916 hectares. These erosion and accretion processes played an active role in the changes of coastline during the study period.

  1. Unsupervised Change Detection for Geological and Ecological Monitoring via Remote Sensing: Application on a Volcanic Area

    Science.gov (United States)

    Falco, N.; Pedersen, G. B. M.; Vilmunandardóttir, O. K.; Belart, J. M. M. C.; Sigurmundsson, F. S.; Benediktsson, J. A.

    2016-12-01

    The project "Environmental Mapping and Monitoring of Iceland by Remote Sensing (EMMIRS)" aims at providing fast and reliable mapping and monitoring techniques on a big spatial scale with a high temporal resolution of the Icelandic landscape. Such mapping and monitoring will be crucial to both mitigate and understand the scale of processes and their often complex interlinked feedback mechanisms.In the EMMIRS project, the Hekla volcano area is one of the main sites under study, where the volcanic eruptions, extreme weather and human activities had an extensive impact on the landscape degradation. The development of innovative remote sensing approaches to compute earth observation variables as automatically as possible is one of the main tasks of the EMMIRS project. Furthermore, a temporal remote sensing archive is created and composed by images acquired by different sensors (Landsat, RapidEye, ASTER and SPOT5). Moreover, historical aerial stereo photos allowed decadal reconstruction of the landscape by reconstruction of digital elevation models. Here, we propose a novel architecture for automatic unsupervised change detection analysis able to ingest multi-source data in order to detect landscape changes in the Hekla area. The change detection analysis is based on multi-scale analysis, which allows the identification of changes at different level of abstraction, from pixel-level to region-level. For this purpose, operators defined in mathematical morphology framework are implemented to model the contextual information, represented by the neighbour system of a pixel, allowing the identification of changes related to both geometrical and spectral domains. Automatic radiometric normalization strategy is also implemented as pre-processing step, aiming at minimizing the effect of different acquisition conditions. The proposed architecture is tested on multi-temporal data sets acquired over different time periods coinciding with the last three eruptions (1980-1981, 1991

  2. Parallel Changes in Intracellular Water Volume and pH Induced by NH3/NH4+ Exposure in Single Neuroblastoma Cells

    Directory of Open Access Journals (Sweden)

    Víctor M. Blanco

    2013-12-01

    Full Text Available Background: Increased blood levels of ammonia (NH3 and ammonium (NH4+, i.e. hyperammonemia, leads to cellular brain edema in humans with acute liver failure. The pathophysiology of this edema is poorly understood. This is partly due to incomplete understanding of the osmotic effects of the pair NH3/NH4+ at the cellular and molecular levels. Cell exposure to solutions containing NH3/NH4+ elicits changes in intracellular pH (pHi, which can in turn affect cell water volume (CWV by activating transport mechanisms that produce net gain or loss of solutes and water. The occurrence of CWV changes caused by NH3/NH4+ has long been suspected, but the mechanisms, magnitude and kinetics of these changes remain unknown. Methods: Using fluorescence imaging microscopy we measured, in real time, parallel changes in pHi and CWV caused by brief exposure to NH3/NH4+ of single cells (N1E-115 neuroblastoma or NG-108 neuroblastoma X glioma loaded with the fluorescent indicator BCECF. Changes in CWV were measured by exciting BCECF at its intracellular isosbestic wavelength (∼438 nm, and pHi was measured ratiometrically. Results: Brief exposure to isosmotic solutions (i.e. having the same osmolality as that of control solutions containing NH4Cl (0.5- 30 mM resulted in a rapid, dose-dependent swelling, followed by isosmotic regulatory volume decrease (iRVD. NH4Cl solutions in which either extracellular [NH3] or [NH4+] was kept constant while the other was changed by varying the pH of the solution, demonstrated that [NH3]o rather than [NH4+]o is the main determinant of the NH4Cl-induced swelling. The iRVD response was sensitive to the anion channel blocker NPPB, and partly dependent on external Ca2+. Upon removal of NH4Cl, cells shrank and displayed isosmotic regulatory volume increase (iRVI. Regulatory volume responses could not be activated by comparable CWV changes produced by anisosmotic solutions, suggesting that membrane stretch or contraction by themselves are

  3. Ambient changes in tracer concentrations from a multilevel monitoring system in Basalt

    Science.gov (United States)

    Bartholomay, Roy C.; Twining, Brian V.; Rose, Peter E.

    2014-01-01

    Starting in 2008, a 4-year tracer study was conducted to evaluate ambient changes in groundwater concentrations of a 1,3,6-naphthalene trisulfonate tracer that was added to drill water. Samples were collected under open borehole conditions and after installing a multilevel groundwater monitoring system completed with 11 discrete monitoring zones within dense and fractured basalt and sediment layers in the eastern Snake River aquifer. The study was done in cooperation with the U.S. Department of Energy to test whether ambient fracture flow conditions were sufficient to remove the effects of injected drill water prior to sample collection. Results from thief samples indicated that the tracer was present in minor concentrations 28 days after coring, but was not present 6 months after coring or 7 days after reaming the borehole. Results from sampling the multilevel monitoring system indicated that small concentrations of the tracer remained in 5 of 10 zones during some period after installation. All concentrations were several orders of magnitude lower than the initial concentrations in the drill water. The ports that had remnant concentrations of the tracer were either located near sediment layers or were located in dense basalt, which suggests limited groundwater flow near these ports. The ports completed in well-fractured and vesicular basalt had no detectable concentrations.

  4. Geophysical Methods for Monitoring Temperature Changes in Shallow Low Enthalpy Geothermal Systems

    Directory of Open Access Journals (Sweden)

    Thomas Hermans

    2014-08-01

    Full Text Available Low enthalpy geothermal systems exploited with ground source heat pumps or groundwater heat pumps present many advantages within the context of sustainable energy use. Designing, monitoring and controlling such systems requires the measurement of spatially distributed temperature fields and the knowledge of the parameters governing groundwater flow (permeability and specific storage and heat transport (thermal conductivity and volumetric thermal capacity. Such data are often scarce or not available. In recent years, the ability of electrical resistivity tomography (ERT, self-potential method (SP and distributed temperature sensing (DTS to monitor spatially and temporally temperature changes in the subsurface has been investigated. We review the recent advances in using these three methods for this type of shallow applications. A special focus is made regarding the petrophysical relationships and on underlying assumptions generally needed for a quantitative interpretation of these geophysical data. We show that those geophysical methods are mature to be used within the context of temperature monitoring and that a combination of them may be the best choice regarding control and validation issues.

  5. Lifetime-resolved photoacoustic (LPA) spectroscopy for monitoring oxygen change and photodynamic therapy (PDT)

    Science.gov (United States)

    Jo, Janggun; Lee, Chang Heon; Kopelman, Raoul; Wang, Xueding

    2016-03-01

    The Methylene Blue loaded Polyacrylamide Nanoparticles (MB-PAA NPs) are used for oxygen sensing and Photodynamic therapy (PDT), a promising therapeutic modality employed for various tumors, with distinct advantages of delivery of biomedical agents and protection from other bio-molecules overcoming inherent limitations of molecular dyes. Lifetime-resolved photoacoustic spectroscopy using quenched-phosphorescence method is applied with MB-PAA NPs so as to sense oxygen, while the same light source is used for PDT. The dye is excited by absorbing 650 nm wavelength light from a pump laser to reach triplet state. The probe laser at 810 nm wavelength is used to excite the first triplet state at certain delayed time to measure the dye lifetime which indicates oxygen concentration. The 9L cells (106 cells/ml) incubated with MB-PAA NP solution are used for monitoring oxygen level change during PDT in situ test. The oxygen level and PDT efficacy are confirmed with a commercial oximeter, and fluorescence microscope imaging and flow cytometry results. This technique with the MB-PAA NPs allowed us to demonstrate a potential non-invasive theragnostic operation, by monitoring oxygen depletion during PDT in situ, without the addition of secondary probes. Here, we demonstrate this theragnostic operation, in vitro, performing PDT while monitoring oxygen depletion. We also show the correlation between O2 depletion and cell death.

  6. COMPARATIVE EVALUATION OF CHANGE IN SALIVARY pH ON CONSUMPTION OF DRY READY TO EAT CEREALS, CEREALS WITH AND WITHOUT ADDED SUGAR IN MILK- AN IN -VIVO STUDY

    OpenAIRE

    Mahesh J*, Sapna B, Veeresh DJ, Divya D

    2016-01-01

    Background: Dry, Ready to Eat Cereals are a combination of refined sugar and starch, most commonly consumed breakfast in the modern human diet. The present study was done to investigate the effects of combination foods on salivary pH. Objective: To assess and compare the salivary pH changes after consumption of Dry Ready to Eat Cereals (REC), Cereals with plain and sugar added milk. Method: Thirty six adults of age 18 to 25 years were assessed for salivary pH at baseline followed by one minut...

  7. Monitoring land use and land cover change in mountain regions: An example in the Jalca grasslands of the Peruvian Andes

    NARCIS (Netherlands)

    Tovar, C.; Seijmonsbergen, A.C.; Duivenvoorden, J.F.

    2013-01-01

    Mountains are rich in biodiversity and provide ecosystem services for their inhabitants. These regions are currently threatened by land use and land cover changes (LUCC), therefore an efficient monitoring is required to capture such changes. The aim of this study is to test a landscape change analys

  8. Monitoring land use and land cover change in mountain regions: An example in the Jalca grasslands of the Peruvian Andes

    NARCIS (Netherlands)

    Tovar, C.; Seijmonsbergen, A.C.; Duivenvoorden, J.F.

    2013-01-01

    Mountains are rich in biodiversity and provide ecosystem services for their inhabitants. These regions are currently threatened by land use and land cover changes (LUCC), therefore an efficient monitoring is required to capture such changes. The aim of this study is to test a landscape change

  9. Environmental change challenges decision-making during post-market environmental monitoring of transgenic crops.

    Science.gov (United States)

    Sanvido, Olivier; Romeis, Jörg; Bigler, Franz

    2011-12-01

    The ability to decide what kind of environmental changes observed during post-market environmental monitoring of genetically modified (GM) crops represent environmental harm is an essential part of most legal frameworks regulating the commercial release of GM crops into the environment. Among others, such decisions are necessary to initiate remedial measures or to sustain claims of redress linked to environmental liability. Given that consensus on criteria to evaluate 'environmental harm' has not yet been found, there are a number of challenges for risk managers when interpreting GM crop monitoring data for environmental decision-making. In the present paper, we argue that the challenges in decision-making have four main causes. The first three causes relate to scientific data collection and analysis, which have methodological limits. The forth cause concerns scientific data evaluation, which is controversial among the different stakeholders involved in the debate on potential impacts of GM crops on the environment. This results in controversy how the effects of GM crops should be valued and what constitutes environmental harm. This controversy may influence decision-making about triggering corrective actions by regulators. We analyse all four challenges and propose potential strategies for addressing them. We conclude that environmental monitoring has its limits in reducing uncertainties remaining from the environmental risk assessment prior to market approval. We argue that remaining uncertainties related to adverse environmental effects of GM crops would probably be assessed in a more efficient and rigorous way during pre-market risk assessment. Risk managers should acknowledge the limits of environmental monitoring programmes as a tool for decision-making.

  10. Using indoor air quality monitoring in 6 counties to change policy in North Carolina.

    Science.gov (United States)

    Proescholdbell, Scott; Steiner, Julea; Goldstein, Adam O; Malek, Sally Herndon

    2009-07-01

    Indoor air quality monitoring has become a valuable tool for states wanting to assess levels of particulate matter before and after smoke-free policies are implemented. However, many states face barriers in passing comprehensive smoke-free legislation, making such study comparisons unlikely. We used indoor air monitoring data to educate decision makers about the value of comprehensive smoke-free laws in a state with strong historical ties to tobacco. We trained teams in 6 counties in North Carolina to monitor air quality in hospitality venues with 1 of 3 possible smoking policy designations: 1) smoke-free, 2) separate smoking and nonsmoking sections (mixed), or 3) smoking allowed in all areas. Teams monitored 152 venues for respirable suspended particles that were less than 2.5 microm in diameter and collected information on venue characteristics. The data were combined and analyzed by venue policy and by county. Our findings were presented to key decision makers, and we then collected information on media publicity about these analyses. Overall, smoke-free venues had the lowest particulate matter levels (15 microg/m3), well below established Environmental Protection Agency standards. Venues with mixed policies and venues that permitted smoking in all areas had particulate matter levels that are considered unhealthy by Environmental Protection Agency standards. The media coverage of our findings included newspaper, radio, and television reports. Findings were also discussed with local health directors, state legislators, and public health advocates. Study data have been used to quantify particulate matter levels, raise awareness about the dangers of secondhand smoke, build support for evidence-based policies, and promote smoke-free policies among policy makers. The next task is to turn this effort into meaningful policy change that will protect everyone from the harms of secondhand smoke.

  11. 76 FR 38360 - Workshop-Monitoring Changes in Extreme Storm Statistics: State of Knowledge; Notice of Open...

    Science.gov (United States)

    2011-06-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Workshop--Monitoring Changes in Extreme Storm Statistics: State of Knowledge; Notice of Open Public Workshop AGENCY: National Environmental Satellite, Data,...

  12. Monitoring changes in anti-tuberculosis treatment: associated factors determined at the time of diagnosis.

    Science.gov (United States)

    Altet, M N; Vidal, R; Milá, C; Rodrigo, T; Casals, M; Mir, I; Ruiz-Manzano, J; Jiménez-Fuentes, M A; Sánchez, F; Maldonado, J; Blanquer, R; de Souza-Galväo, M L; Solsona, J; Azlor, E; Díaz, D; Calpe, J L; Caylá, J A

    2013-11-01

    To determine predictive factors for changes in standard anti-tuberculosis chemotherapy at the time of diagnosis. A prospective study was performed among tuberculosis (TB) patients treated at specialised centres during 2008-2009. Treatment outcome was monitored per standard guidelines. Treatment was considered successful if the patient was cured or completed treatment. Factors associated with treatment modification were analysed at the bivariate and multivariate levels using logistic regression. A total of 427 patients were included in the study. The initial standard treatment regimen was retained for 249 patients (58.3%), extended to 9 months for 36 (8.4%) and changed for 142 (33.3%). Factors associated with a change of regimen at the multivariate level were female sex, age ≥ 50 years, human immunodeficiency virus infection, comorbidities, alcoholism, hospitalisation and culture-positive sputum. Drug resistance and toxicity were analysed independently. Treatment outcome was successful in 97.2% of cases without a regimen change and in 87.3% of those with a changed regimen (P tuberculosis regimen should be considered for rigorous follow-up. Results obtained through individualised treatment provided by specialists were good despite the complexity of the cases treated.

  13. Development of Distributed Research Center for monitoring and projecting regional climatic and environmental changes: first results

    Science.gov (United States)

    Gordov, Evgeny; Shiklomanov, Alexander; Okladinikov, Igor; Prusevich, Alex; Titov, Alexander

    2016-04-01

    Description and first results of the cooperative project "Development of Distributed Research Center for monitoring and projecting of regional climatic and environmental changes" recently started by SCERT IMCES and ESRC UNH are reported. The project is aimed at development of hardware and software platform prototype of Distributed Research Center (DRC) for monitoring and projecting regional climatic and environmental changes over the areas of mutual interest and demonstration the benefits of such collaboration that complements skills and regional knowledge across the northern extratropics. In the framework of the project, innovative approaches of "cloud" processing and analysis of large geospatial datasets will be developed on the technical platforms of two U.S. and Russian leading institutions involved in research of climate change and its consequences. Anticipated results will create a pathway for development and deployment of thematic international virtual research centers focused on interdisciplinary environmental studies by international research teams. DRC under development will comprise best features and functionality of earlier developed by the cooperating teams' information-computational systems RIMS (http://rims.unh.edu) and CLIMATE(http://climate.scert.ru/), which are widely used in Northern Eurasia environment studies. The project includes several major directions of research (Tasks) listed below. 1. Development of architecture and defining major hardware and software components of DRC for monitoring and projecting of regional environmental changes. 2. Development of an information database and computing software suite for distributed processing and analysis of large geospatial data hosted at ESRC and IMCES SB RAS. 3. Development of geoportal, thematic web client and web services providing international research teams with an access to "cloud" computing resources at DRC; two options will be executed: access through a basic graphical web browser and

  14. The rhizosphere pH change of Pinus koraiensis seedlings as affected by N sources of different levels and its effect on the availability and uptake of Fe, Mn, Cu and Zn

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Dark brown forest soil was collected from the upper 20 cm soil layer in Changbai Mountain Research Station of Ecosystem, Chinese Academy of Sciences. The soil was amended with two different forms of nitrogen fertilizers: NO3- as Ca(NO3)2, NH4+ as NH4Cl at the concentrations of 50, 100, 200 and 400 mg?kg-1 respectively. The experiment was carried out with 2-yr-old Pinus koraiensis seedlings in pot. The pH change of rhizosphere soil and the contents of available Fe, Mn, Cu, and Zn in soil and leaves were analyzed. The result indicated that the addition of NH4--N decreased the rhizosphere pH value, while the addition of NO3--N increased the rhizosphere pH value in contrast with the control treatment. The direction and extent of the pH change mainly depended on N source and its concentrations applied. The rhizosphere pH change had a remarkable influence on the availability of the micronutrients in the rhizosphere, and thereafter affected the nutrient uptake by the seedlings. The contents of available mineral nutrients had a negative correlation with the pH value in the rhizosphere soil. The contents of available mineral nutrients in leaves were positively correlated to the levels of the available nutrients in the rhizosphere soils.

  15. Monitoring Educational Organizations' Culture of Sustainable Consumption: Initiating and Evaluating Cultural Change in Schools and Universities

    Directory of Open Access Journals (Sweden)

    Daniel Fischer

    2011-01-01

    Full Text Available Problem Statement: Patterns of consumption are considered as a main driver of unsustainable development. In the debate, education and educational organizations are unisonous considered as a key player to contribute to a more sustainable socialization of young consumers. Both schools and universities are challenged to become places and life-worlds in which sustainable consumption can be learned and experienced. The objective of this paper was to explore how educational organizations can effectively engage their members in bringing about the aspired transformations and monitoring their effects. Approach: The study used a conceptual approach that included three steps. Firstly, the concept of an educational organization’s Culture Of Consumption (COC was adopted as an analytical frame of reference. In a second step, methodological propositions for changing the organizational COC were discussed drawing on the concepts of mode-2 knowledge production and participatory change management. In a third step, existing tools and approaches to sustainability auditing in the educational context were screened and critically discussed against the background of recent innovations in mode-2 approaches to sustainability evaluation. Results: The findings revealed that while existing sets of indicators did adequately account for key consumption-related organizational operations and to some extent for educational goals and aspirations, they failed to tap the realm of underlying and tacit basic assumptions that substantiate the essence of an organizational COC. To remedy this shortcoming, additional indicators and modifications were proposed. As a synthesis, a synoptic framework of a monitoring system for an educational organization’s COC was presented. Conclusion: The study’s results highlighted the need to develop monitoring frameworks that go beyond assessing operative performances and pay greater attention to reflective, interpretative and deliberative

  16. Monitoring groundwater storage change in Mekong Delta using Gravity Recovery and Climate Experiment (GRACE) data

    Science.gov (United States)

    Aierken, A.; Lee, H.; Hossain, F.; Bui, D. D.; Nguyen, L. D.

    2016-12-01

    The Mekong Delta, home to almost 20 million inhabitants, is considered one of the most important region for Vietnam as it is the agricultural and industrial production base of the nation. However, in recent decades, the region is seriously threatened by variety of environmental hazards, such as floods, saline water intrusion, arsenic contamination, and land subsidence, which raise its vulnerability to sea level rise due to global climate change. All these hazards are related to groundwater depletion, which is the result of dramatically increased over-exploitation. Therefore, monitoring groundwater is critical to sustainable development and most importantly, to people's life in the region. In most countries, groundwater is monitored using well observations. However, because of its spatial and temporal gaps and cost, it is typically difficult to obtain large scale, continuous observations. Since 2002, the Gravity Recovery and Climate Experiment (GRACE) satellite gravimetry mission has delivered freely available Earth's gravity variation data, which can be used to obtain terrestrial water storage (TWS) changes. In this study, the TWS anomalies over the Mekong Delta, which are the integrated sum of anomalies of soil moisture storage (SMS), surface water storage (SWS), canopy water storage (CWS), groundwater storage (GWS), have been obtained using GRACE CSR RL05 data. The leakage error occurred due to GRACE signal processing has been corrected using several different approaches. The groundwater storage anomalies were then derived from TWS anomalies by removing SMS, and CWS anomalies simulated by the four land surface models (NOAH, CLM, VIC and MOSAIC) in the Global Land Data Assimilation System (GLDAS), as well as SWS anomalies estimated using ENVISAT satellite altimetry and MODIS imagery. Then, the optimal GRACE signal restoration method for the Mekong Delta is determined with available in-situ well data. The estimated GWS anomalies revealed continuously decreasing

  17. Integrated monitoring and information systems for managing aquatic invasive species in a changing climate

    Science.gov (United States)

    Lee, Henry; Reusser, Deborah A.; Olden, Julian D.; Smith, Scott S.; Graham, Jim; Burkett, Virginia; Dukes, Jeffrey S.; Piorkowski, Robert J.; Mcphedran, John

    2008-01-01

    Changes in temperature, precipitation, and other climatic drivers and sea-level rise will affect populations of existing native and non-native aquatic species and the vulnerability of aquatic environments to new invasions. Monitoring surveys provide the foundation for assessing the combined effects of climate change and invasions by providing baseline biotic and environmental conditions, although the utility of a survey depends on whether the results are quantitative or qualitative, and other design considerations. The results from a variety of monitoring programs in the United States are available in integrated biological information systems, although many include only non-native species, not native species. Besides including natives, we suggest these systems could be improved through the development of standardized methods that capture habitat and physiological requirements and link regional and national biological databases into distributed Web portals that allow drawing information from multiple sources. Combining the outputs from these biological information systems with environmental data would allow the development of ecological-niche models that predict the potential distribution or abundance of native and non-native species on the basis of current environmental conditions. Environmental projections from climate models can be used in these niche models to project changes in species distributions or abundances under altered climatic conditions and to identify potential high-risk invaders. There are, however, a number of challenges, such as uncertainties associated with projections from climate and niche models and difficulty in integrating data with different temporal and spatial granularity. Even with these uncertainties, integration of biological and environmental information systems, niche models, and climate projections would improve management of aquatic ecosystems under the dual threats of biotic invasions and climate change

  18. In situ monitoring of structural changes during colloidal self-assembly.

    Science.gov (United States)

    Koh, Yaw Koon; Wong, Chee Cheong

    2006-01-31

    Reflectance spectroscopy is utilized to monitor structural changes during the self-assembly of a monodisperse colloidal system at the meniscus of a sessile drop on an inert substrate. Treating the ordered colloidal structure as a photonic crystal is equivalent to monitoring the changes in the photonic band gap (PBG) as the colloidal system self-assembles heterogeneously into a crystal through solvent evaporation in ambient conditions. Using a modified Bragg's law model of the photonic crystal, we can trace the structural evolution of the self-assembling colloidal system. After a certain induction period, a face-centered cubic (FCC) structure emerges, albeit with a lattice parameter larger than that of a true close-packed structure. This FCC structure is maintained while the lattice parameter shrinks continuously with further increase in the colloidal concentration due to drying. When the structure reaches a lattice parameter 1.09 times the size of that of a true close-packed structure, it undergoes an abrupt decrease in lattice spacing, apparently similar to those reported for lattice-distortive martensitic transformations. This abrupt final lattice shrinkage agrees well with the estimated Debye screening length of the electric double layer of charged colloids and could be the fundamental reason behind the cracking commonly seen in colloidal crystals.

  19. Diffuse optical monitoring of hemodynamic changes in piglet brain with closed head injury

    Science.gov (United States)

    Zhou, Chao; Eucker, Stephanie A.; Durduran, Turgut; Yu, Guoqiang; Ralston, Jill; Friess, Stuart H.; Ichord, Rebecca N.; Margulies, Susan S.; Yodh, Arjun G.

    2009-05-01

    We used a nonimpact inertial rotational model of a closed head injury in neonatal piglets to simulate the conditions following traumatic brain injury in infants. Diffuse optical techniques, including diffuse reflectance spectroscopy and diffuse correlation spectroscopy (DCS), were used to measure cerebral blood oxygenation and blood flow continuously and noninvasively before injury and up to 6 h after the injury. The DCS measurements of relative cerebral blood flow were validated against the fluorescent microsphere method. A strong linear correlation was observed between the two techniques (R=0.89, p<0.00001). Injury-induced cerebral hemodynamic changes were quantified, and significant changes were found in oxy- and deoxy-hemoglobin concentrations, total hemoglobin concentration, blood oxygen saturation, and cerebral blood flow after the injury. The diffuse optical measurements were robust and also correlated well with recordings of vital physiological parameters over the 6-h monitoring period, such as mean arterial blood pressure, arterial oxygen saturation, and heart rate. Finally, the diffuse optical techniques demonstrated sensitivity to dynamic physiological events, such as apnea, cardiac arrest, and hypertonic saline infusion. In total, the investigation corraborates potential of the optical methods for bedside monitoring of pediatric and adult human patients in the neurointensive care unit.

  20. Changes in texture of yogurt from goatcs milk modified by transglu-taminase depending on pH of the milk

    OpenAIRE

    2007-01-01

    Set yogurt from goatcs milk with adjusted pH to 6,4, 6,3, 6,2 and 6,1 and than modified by microbial transglutaminase (TGase) were produced. Control yogurt was produced from goatcs milk of pH 6,4 but without modification by TGase. In yogurt determined sensory quality, pH, texture parameters and syneresis. Modification of goatcs milk by TGase caused an increase in apparent viscosity, hardness and adhesiveness of the yogurt. The pH of the milk incubated with TGase in the range 6.4- 6.1 has no i...

  1. 酸雨观测中pH测量负偏差的统计分析%The Statistical Characteristics of pH Measurement Bias in the Monitoring Data of CMA-ARMN

    Institute of Scientific and Technical Information of China (English)

    汤洁; 巴金

    2013-01-01

    Precipitation pH and conductivity are measured routinely in the nation-wide network with more than 300 stations, known as the Acid Rain Monitoring Network (ARMN), under the infrastructure of China Meteorological Administration (CMA) since early 1990s. Previous studies indicate that a systematic negative bias in the pH measurement, caused by the aging of pH electrode, which has weakened the data quality obviously. Characteristics of the bias are investigated to describe the temporal and spatial features of the negative pH measurement bias (NBpH) and to estimate its magnitude with meticulous statistical approaches, based on the monitoring dataset obtained from CMA-ARMN during 1992—2011. The result indicates that 40% stations of CMA-ARMN suffers from NBpH problem in the early 1990s, while this ratio decreases to 25% during 2010—2011. The proportion of data infected with NBpH problem during 2010— 2011 reduces to 2% from 10% in the early 1990s. This improvement of pH measurement mentioned above can be attributed to the renewal of pH meter for all CMA-ARMN stations in 2000, the re-approval of Standard Operation Manual of CMA-ARMN in 2005, and the recent trail measures on the pH electrode aging. Also, statistics shows that NBpH problem seldom occurs in the stations over the Northwest China and Qinghai-Tibet Plateau, but frequently occurs in the stations of other regions over China. On the whole, NBpH problem in southern part of China is more serious than those in the northern part of China. This geographical feature of NBpH is related with the behavior of aged pH electrode which shows bigger negative bias when measuring the solution of low pH and low conductivity. Quasi-quantitative estimation of NBpH based on the K-pH inequality principle shows that the magnitude of NBpH for about 80% data ranges from —0. 6 to 0, with a few of extremes lower than —3. 0. The lower pH is, the larger NBpH tends to be. To avoid NBpH problem in future, substitution of the now

  2. Challenges of correlating pH change with relief of clinical symptoms in gastro esophageal reflux disease: a phase III, randomized study of Zegerid versus Losec.

    Directory of Open Access Journals (Sweden)

    Dave Walker

    Full Text Available Zegerid (on demand immediate-release omeprazole and sodium bicarbonate combination therapy has demonstrated earlier absorption and more rapid pH change compared with Losec (standard enteric coated omeprazole, suggesting more rapid clinical relief of heartburn. This Phase III, multicenter, double-blind, double-dummy, randomized study assessed the clinical superiority of Zegerid versus Losec for rapid relief of heartburn associated with gastro-esophageal reflux disease (GERD.Patients with a history of frequent (2 3 days/week uncomplicated GERD, were randomized to receive Zegerid (20 mg or Losec (20 mg with corresponding placebo. Study medication was self-administered on the first episode of heartburn, and could be taken for up to 3 days within a 14 day study period. Heartburn severity was self assessed up to 180 minutes post dose (9 point Likert scale. Primary endpoint was median time to sustained response (≥3 point reduction in heartburn severity for ≥45 minutes.Of patients randomized to Zegerid (N=122 or Losec (N=117, 228/239 had recorded ≥1 evaluable heartburn episodes and were included in the modified intent-to-treat population. No significant between-group differences were observed for median time to sustained response (60.0 vs. 52.2 minutes, Zegerid [N=117] and Losec [N=111], respectively, sustained partial response (both, 37.5 minutes and sustained total relief (both, 105 minutes. Significantly more patients treated with Zegerid reached sustained total relief within 0-30 minutes post dose in all analysis sets (p<0.05. Both treatments were well tolerated and did not raise any safety concerns.Superiority of Zegerid over Losec for rapid heartburn relief was not demonstrated; both treatments were equally effective however the rapid onset of action of Losec was unexpected. Factors, including aspects of study design may have contributed to this. This study supports previously reported difficulty in correlating intra-gastric pH change with

  3. Integration of European habitat monitoring based on plant life form composition as an indicator of environmental change and change in biodiversity

    DEFF Research Database (Denmark)

    Bloch-Petersen, Margit; Brandt, Jesper; Olsen, Martin

    2006-01-01

    led to the re-introduction of Raunkiaer's plant life form concept. This approach enables the indication of changes in biodiversity based on alterations in general habitat composition and quality. Although the objectives of the SBMP and the BioHab projects have been somewhat different......  During the last 25 years a number of European countries have developed general landscape monitoring systems. In the agricultural landscapes of Denmark the Small Biotope Monitoring Program (SBMP), which focuses on the dynamics of small biotopes and their relation to changes in agricultural...... related habitat monitoring. This has been through the BioHab Concerted Action Framework Programme of the EU (2002-2005), and the resulting publication of a handbook for recording and monitoring habitats (Bunce et al., 2005). The focus on environmentally conditioned habitat changes at a landscape level has...

  4. Real-time monitoring of protein conformational changes using a nano-mechanical sensor.

    Directory of Open Access Journals (Sweden)

    Livan Alonso-Sarduy

    Full Text Available Proteins can switch between different conformations in response to stimuli, such as pH or temperature variations, or to the binding of ligands. Such plasticity and its kinetics can have a crucial functional role, and their characterization has taken center stage in protein research. As an example, Topoisomerases are particularly interesting enzymes capable of managing tangled and supercoiled double-stranded DNA, thus facilitating many physiological processes. In this work, we describe the use of a cantilever-based nanomotion sensor to characterize the dynamics of human topoisomerase II (Topo II enzymes and their response to different kinds of ligands, such as ATP, which enhance the conformational dynamics. The sensitivity and time resolution of this sensor allow determining quantitatively the correlation between the ATP concentration and the rate of Topo II conformational changes. Furthermore, we show how to rationalize the experimental results in a comprehensive model that takes into account both the physics of the cantilever and the dynamics of the ATPase cycle of the enzyme, shedding light on the kinetics of the process. Finally, we study the effect of aclarubicin, an anticancer drug, demonstrating that it affects directly the Topo II molecule inhibiting its conformational changes. These results pave the way to a new way of studying the intrinsic dynamics of proteins and of protein complexes allowing new applications ranging from fundamental proteomics to drug discovery and development and possibly to clinical practice.

  5. Monitoring the Philippine Forest Cover Change Using Ndvi Products of Remote Sensing Data

    Science.gov (United States)

    Torres, R. C.; Mouginis-Mark, P.; Wright, R.; Garbeil, H.; Craig, B.

    2004-12-01

    The Philippines has one of the world's fastest disappearing forest cover, which is being lost to natural processes and landscape-modifying human activities. Currently, forested landscape covers 24% (i.e., 7.2 million hectares) of the Philippines' total land area, of which only 800,000 hectares are considered as old-growth forests. Occasionally, volcanic activities and earthquakes cause large-scale impacts on the forest cover, but the systematic reduction of the country's forest has been sustained through unregulated logging operations and other human-induced landscape modification. Reforestation and watershed protection have become important public policy programs as forest denudation is linked to recent devastating landslides, debris flows and flashfloods. However, many watershed areas that are at risk to deforestation are hardly accessible to ground-based monitoring. A spaced-based monitoring system facilitates an efficient and timely response to changes in the quality and extent of the Philippine forest cover. This monitoring system relies in the generation of Normalized Difference Vegetation Index (NDVI) products from the red and infrared bands of remote sensing data, which correlates with the amount of chlorophyll in the vegetation. Given the existing forest classification maps, non-forested regions are masked in the data analysis, so that only forest-related changes in the vegetation are shown in the NDVI image difference products. A combination of two MODIS-bearing satellites, i.e., Terra and Aqua, acquire high temporal and moderate spatial resolution data, enabling the countrywide detection of vegetation changes within a certain observation period. MODIS data are calibrated for setting the pixel quality thresholds, which minimize the artifact of clouds and haze in the analysis. Areas showing dramatic changes are further investigated using higher resolution data, such as ASTER and Landsat 7 ETM. Sequential NDVI products of remote sensing data provide

  6. In Vivo Monitoring of Hemodynamic Changes during Clogging and Unclogging of Blood Supply for the Application of Clinical Shock Detection

    Science.gov (United States)

    Kanawade, Rajesh; Stelzle, Florian; Schmidt, Michael

    This paper presents a novel methodology in early detection of clinical shock by monitoring hemodynamic changes using diffuse reflectance measurement technique. Detailed prototype of the reflectance measurement system and data analysis technique of hemodynamic monitoring was carried out in our laboratory. The real time in-vivo measurements were done from the index finger. This study demonstrates preliminary results of real time monitoring of reduced/- oxyhemoglobin changes during clogging and unclogging of blood flow in the finger tip. The obtained results were verified with pulse-oximeter values, connected to the tip of the same index finger.

  7. AVHRR, MODIS and Landsat Time Series for the Monitoring of Vegetation Changes Around the World (Invited)

    Science.gov (United States)

    de Beurs, K.; Owsley, B.; Julian, J.; Henebry, G. M.

    2013-12-01

    A confluence of computing power, cost of storage, ease of access to data, and ease of product delivery make it possible to harness the power of multiple remote sensing data streams to monitor land surface dynamics. Change detection has always been a fundamental remote sensing task, and there are myriad ways to perceive differences. From a statistical viewpoint, image time series of the vegetated land surface are complicated data to analyze. The time series are often seasonal and have high temporal autocorrelation. These characteristics result in the failure of the data to meet the assumption of most standard parametric statistical tests. Failure of statistical assumptions is not trivial and the use of inappropriate statistical methods may lead to the detection of spurious trends, while any actual trends and/or step changes might be overlooked. While the analysis of messy data, which can be influenced by discontinuity, missing observation, non-linearity and seasonality, is still developing within the remote sensing community, other scientific research areas routinely encounter similar problems and have developed statistically appropriate ways to deal with them. In this talk we describe the process of change analysis as a sequence of tasks: (1) detection of changes; (2) quantification of changes; (3) assessment of changes; (4) attribution of changes; and (5) projection of the potential consequences of changes. To detect, quantify, and assess the significance of broad scale land surface changes, we will first apply the nonparametric Seasonal Kendall (SK) trend test corrected for first-order temporal autocorrelation to MODIS image time series. We will then discuss three case studies, situated in the USA, Russia, and New Zealand in which we combine or fuse satellite data at two spatial resolutions (30m Landsat and 500m MODIS) to assess and attribute changes at fine spatial and temporal scales. In the USA we will investigate changes as a result of urban development, in

  8. Preface: Monitoring and modelling to guide coastal adaptation to extreme storm events in a changing climate

    Science.gov (United States)

    Brown, J. M.; Ciavola, P.; Masselink, G.; McCall, R.; Plater, A. J.

    2016-02-01

    Storms across the globe and their associated consequences in coastal zones (flooding and erosion), combined with the long-term geomorphic evolution of our coastlines, are a threat to life and assets, both socioeconomic and environmental. In a changing climate, with a rising global sea level, potentially changing patterns in storm tracks and storminess, and rising population density and pressures on the coastal zone, the future risk of coastal storm impacts is likely to increase. Coastal managers and policy makers therefore need to make effective and timely decisions on the use of resources for the immediate and longer Research focused on "monitoring and modelling to guide coastal adaptation to extreme storm events in a changing climate" is becoming more common; its goal is to provide science-based decision support for effective adaptation to the consequences of storm impacts, both now and under future climate scenarios at the coast. The growing transfer of information between the science community and end-users is enabling leading research to have a greater impact on the socioeconomic resilience of coastal communities. This special issue covers recent research activities relating to coastal hazard mapping in response to extreme events, economic impacts of long-term change, coastal processes influencing management decisions and the development of online decision support tools.

  9. Monitoring transcranial direct current stimulation induced changes in cortical excitability during the serial reaction time task.

    Science.gov (United States)

    Ambrus, Géza Gergely; Chaieb, Leila; Stilling, Roman; Rothkegel, Holger; Antal, Andrea; Paulus, Walter

    2016-03-11

    The measurement of the motor evoked potential (MEP) amplitudes using single pulse transcranial magnetic stimulation (TMS) is a common method to observe changes in motor cortical excitability. The level of cortical excitability has been shown to change during motor learning. Conversely, motor learning can be improved by using anodal transcranial direct current stimulation (tDCS). In the present study, we aimed to monitor cortical excitability changes during an implicit motor learning paradigm, a version of the serial reaction time task (SRTT). Responses from the first dorsal interosseous (FDI) and forearm flexor (FLEX) muscles were recorded before, during and after the performance of the SRTT. Online measurements were combined with anodal, cathodal or sham tDCS for the duration of the SRTT. Negative correlations between the amplitude of online FDI MEPs and SRTT reaction times (RTs) were observed across the learning blocks in the cathodal condition (higher average MEP amplitudes associated with lower RTs) but no significant differences in the anodal and sham conditions. tDCS did not have an impact on SRTT performance, as would be predicted based on previous studies. The offline before-after SRTT MEP amplitudes showed an increase after anodal and a tendency to decrease after cathodal stimulation, but these changes were not significant. The combination of different interventions during tDCS might result in reduced efficacy of the stimulation that in future studies need further attention.

  10. Noninvasive Monitoring of Training Induced Muscle Adaptation with -MRS: Fibre Type Shifts Correlate with Metabolic Changes

    Directory of Open Access Journals (Sweden)

    Eike Hoff

    2013-01-01

    Full Text Available Purpose. To evaluate training induced metabolic changes noninvasively with magnetic resonance spectroscopy (-MRS for measuring muscle fibre type adaptation. Methods. Eleven volunteers underwent a 24-week training, consisting of speed-strength, endurance, and detraining (each 8 weeks. Prior to and following each training period, needle biopsies and -MRS of the resting gastrocnemius muscle were performed. Fibre type distribution was analyzed histologically and tested for correlation with the ratios of high energy phosphates ([PCr]/[], [PCr]/[βATP] and [PCr + ]/[βATP]. The correlation between the changes of the -MRS parameters during training and the resulting changes in fibre composition were also analysed. Results. We observed an increased type-II-fibre proportion after speed-strength and detraining. After endurance training the percentage of fast-twitch fibres was reduced. The progression of the [PCr]/[]-ratio was similar to that of the fast-twitch fibres during the training. We found a correlation between the type-II-fibre proportion and [PCr]/[] (, or [PCr]/[βATP] (, ; the correlations between its changes (delta and the fibre-shift were significant as well (delta[PCr]/[] , delta[PCr]/[βATP] , . Conclusion. Shifts in fibre type composition and high energy phosphate metabolite content covary in human gastrocnemius muscle. Therefore -MRS might be a feasible method for noninvasive monitoring of exercise-induced fibre type transformation.

  11. Optimized noninvasive monitoring of thermal changes on digital B-mode renal sonography during revascularization therapy.

    Science.gov (United States)

    Abolhassani, Mohammad D; Tavakoli, Vahid; Sahba, Nima

    2009-11-01

    Noninvasive real-time thermal change monitoring of human internal organs can play a critical role in diagnosis and treatment of many disorders, including reperfusion of renal arteries during anticoagulation therapy. This article focuses on tissue temperature detection using ultrasound velocity changes in different structures and their related speckle shift from their primary locations on high-quality B-mode digital sonography. We evaluated different speckle-tracking techniques and optimized them using appropriate motion estimation methods to determine the best algorithm and parameters. Performing thermal detection methods on simulated phantoms showed a good correlation between speckle shifts and the ground truth temperature. For the simulated images, average thermal error was 0.5 degrees C with an SD of 0.5 degrees C, where lower errors can be obtained in noiseless (motionless) data. The proposed technique was evaluated on real in vivo cases during surgical occlusion and reopening of the renal segmental artery and showed the potential of the algorithm for observation of internal organ changes using only digital ultrasound systems for diagnosis and therapy. The adaptive Rood pattern search proved to be the best block-matching technique, whereas the multiresolution Horn-Schunck technique was the best gradient optical flow method. The extracted thermal change during in vivo revascularization therapy is promising. In addition, we present an evaluation of several block-matching and optical flow motion estimation techniques.

  12. Transmembrane pH gradients in vivo: measurements using fluorinated vitamin B6 derivatives.

    Science.gov (United States)

    Mason, R P

    1999-06-01

    It is well recognized that pH plays a significant regulatory role in most cellular processes. Increasingly, there is interest in transmembrane pH gradients, particularly with respect to tumor growth and response to therapy. NMR offers a non-invasive approach to monitoring cellular pH and detecting changes in response to interventions. This review will consider the strengths of various approaches to measuring pH with particular focus on the reporter molecules designed to interrogate the cellular milieu. In particular, fluorinated vitamin B6 derivatives (6-fluoropyridoxol and 6-fluoropyridoxamine) will be described, which for the first time provide a practical non-destructive method to measure simultaneously intra- and extracellular pH, i.e., the transmembrane pH gradient in animals in vivo based on a single reporter molecule.

  13. Correlation between annual gravity changes monitored by GRACE and background seismicity rates

    Science.gov (United States)

    Mitsui, Y.; Yamada, K.

    2016-12-01

    GRACE(Gravity Recovery and Climate Experiment) has monitored global gravity changes after 2002.Indeed the gravity changes include signals of mass redistribution by M9-classmega-earthquakes (Han et al., 2006; Matsuo and Heki, 2011) and uplift by a deep earthquake (Tanaka et al., 2015),but most of them represent water mass movements (ex. Wahr et al., 2004). Water mass movements around the surfacemay affect earthquake occurrences via surface loads or pore pressure increases (ex. Ellsworth, 2013).Thus we examine the relation between temporal gravity changes and earthquake occurrences in a global scale. We use the GRACE level-3 data (for land) analyzed by UTCSR. The observation period is from April, 2002to January, 2015. The sampling interval is about 1 month. For deficient data, we linearly interpolate themfrom the last and next data. Then we estimate linear trends and amplitudes of annual changes. We also use seismicity catalogue data from USGS and select earthquakes over M4 and whose focal depths areshallower than 30 km. In order to exclude effects of aftershocks of large earthquakes, we extractbackground seismicity µ in the ETAS model (Ogata, 1988). We need sufficient numbers of earthquakesin each spatial grid for stable estimation. Therefore we first separate the surface of the Earth intolarge spatial grids and next select grids where mean values of the earthquake numberswere over three per month. We estimated the background seismicity rates, the linear gravity trends, andthe amplitudes of the annual gravity changes in the selected grids. We find that the correlation coefficient between the background seismicity rate and the annual gravity change is about 0.60 (p-value is 0.002), whereas that of the linear gravity trend between the background seismicity rateis about -0.03. This result implies that annual water movements truly affected the earthquake occurrences, butsecular movements did not.

  14. Multiscale Monitoring and Analysis of the Impacts of Rural Land Use Changes on Downstream Flooding

    Science.gov (United States)

    Geris, J.; Ewen, J.; O'Donnell, G.; O'Connell, P. E.

    2010-12-01

    Recent dramatic flood events in several parts of the world have reignited the debate on the role played by rural land use/management changes (RLUMC). Whereas the effects of RLUMC on runoff generation and flood risk at small scales are often clear, it is difficult to determine how these effects travel through the river network to affect flooding at larger scales downstream. The headwaters of the River Hodder catchment (260 km2) in Northwest England, United Kingdom, have recently undergone widespread RLUMC, including changes in stocking density, blocking of moorland drainage ditches, and woodland planting. An unusually dense nested monitoring network has been set-up so that the effects of RLUMC can be studied at increasing scales, from the process scale (~1 ha) to the meso scale (~100 km2). The stream gauges are nested up to 5 deep. In total there are 27 stream gauges, 7 rain gauges, and 1 weather station. The main effort in analysis has focussed on detecting signals from stocking density changes, by studying pre-change and post-change runoff and river network flows at increasing scales. The field data set available for the analysis is comprehensive but is relatively short (approximately 1 year pre-change and 1 year post-change). Given the natural variability of rainfall and hydrological response, working with such short records is an important challenge, especially as there is an almost universal lack of comprehensive, nested, long-term historical data sets worldwide that could be used to investigate the effects of RLUMC on flooding. An analysis of a commonly used statistical data analysis method (based on data based mechanistic modelling) showed that, for such short records, any change effects from RLUMC are apparently masked by natural variability. In addition, the effects of some types of RLUMC, including changes in stocking density, need several years to be fully established. Analysis methods have therefore been sought that are sensitive to changes in the

  15. Isocratic LC-DAD-FLD method for the determination of flavonoids in paprika samples by using a rapid resolution column and post-column pH change.

    Science.gov (United States)

    Monago-Maraña, Olga; Muñoz de la Peña, Arsenio; Galeano-Díaz, Teresa

    2016-05-15

    The determination of flavonoid compounds in paprika samples has been performed by liquid chromatography in series diode array and fluorescence detection (LC-DAD-FLD), by means of a pH change to basic medium just before FLD detection. The validation of the method was performed through the establishment of the external standard calibration curves and the analytical figures of merit. Limits of detection ranging from 0.006 to 0.02 mg L(-1) and 0.007 to 0.09 mg L(-1) were achieved using DAD and FLD detection, respectively. The experimental conditions to carry out the hydrolysis procedure to obtain flavonoid aglycones from flavonoid glycosides have been optimized applying an experimental design and the response surface methodology. The final conditions selected were 2.5M HCl during 45 min at 85°C. The repeatability of this procedure was assayed and relative standard deviation (RSD) values for concentration of quercetin and luteolin compounds were lower than 2%. The quantification of quercetin, luteolin and kaempferol compounds was carried out in less than 6 min in paprika samples by means of the external standard calibration. The analytes were extracted with methanol and the extracts were previously subjected to a cleanup procedure to extend the use of the chromatographic column.

  16. Retention of ionisable compounds on high-performance liquid chromatography XVII. Estimation of the pH variation of aqueous buffers with the change of the methanol fraction of the mobile phase.

    Science.gov (United States)

    Subirats, Xavier; Bosch, Elisabeth; Rosés, Martí

    2007-01-05

    The use of methanol-aqueous buffer mobile phases in HPLC is a common election when performing chromatographic separations of ionisable analytes. The addition of methanol to the aqueous buffer to prepare such a mobile phase changes the buffer capacity and the pH of the solution. In the present work, the variation of these buffer properties is studied for acetic acid-acetate, phosphoric acid-dihydrogenphosphate-hydrogenphosphate, citric acid-dihydrogencitrate-hydrogencitrate-citrate, and ammonium-ammonia buffers. It is well established that the pH change of the buffers depends on the initial concentration and aqueous pH of the buffer, on the percentage of methanol added, and on the particular buffer used. The proposed equations allow the pH estimation of methanol-water buffered mobile phases up to 80% in volume of organic modifier from initial aqueous buffer pH and buffer concentration (before adding methanol) between 0.001 and 0.01 mol L(-1). From both the estimated pH values of the mobile phase and the estimated pKa of the ionisable analytes, it is possible to predict the degree of ionisation of the analytes and therefore, the interpretation of acid-base analytes behaviour in a particular methanol-water buffered mobile phase.

  17. Seasonal Change in Wetland Coherence as an Aid to Wetland Monitoring

    Directory of Open Access Journals (Sweden)

    Brian Brisco

    2017-02-01

    Full Text Available Water is an essential natural resource, and information about surface water conditions can support a wide variety of applications, including urban planning, agronomy, hydrology, electrical power generation, disaster relief, ecology and preservation of natural areas. Synthetic Aperture Radar (SAR is recognized as an important source of data for monitoring surface water, especially under inclement weather conditions, and is used operationally for flood mapping applications. The canopy penetration capability of the microwaves also allows for mapping of flooded vegetation as a result of enhanced backscatter from what is generally believed to be a double-bounce scattering mechanism between the water and emergent vegetation. Recent investigations have shown that, under certain conditions, the SAR response signal from flooded vegetation may remain coherent during repeat satellite over-passes, which can be exploited for interferometric SAR (InSAR measurements to estimate changes in water levels and water topography. InSAR results also suggest that coherence change detection (CCD might be applied to wetland monitoring applications. This study examines wetland vegetation characteristics that lead to coherence in RADARSAT-2 InSAR data of an area in eastern Canada with many small wetlands, and determines the annual variation in the coherence of these wetlands using multi-temporal radar data. The results for a three-year period demonstrate that most swamps and marshes maintain coherence throughout the ice-/snow-free time period for the 24-day repeat cycle of RADARSAT-2. However, open water areas without emergent aquatic vegetation generally do not have suitable coherence for CCD or InSAR water level estimation. We have found that wetlands with tree cover exhibit the highest coherence and the least variance; wetlands with herbaceous cover exhibit high coherence, but also high variability of coherence; and wetlands with shrub cover exhibit high coherence, but

  18. Monitoring seismic velocity changes caused by the 2014 Northern Aegean earthquake using continuous ambient noise records

    Science.gov (United States)

    Evangelidis, Christos; Daskalakis, Emmanouil; Tsogka, Chrysoula

    2016-04-01

    The 24 May 2014 Northern Aegean earthquake (6.9 Mw), an event on the Northern Aegean Trough (NAT), ruptured on two different fault segments with a total ruptured length of ~100 km. For the second delayed segment, rupture propagated eastward from the hypocenter for ˜65 km with a supershear velocity (5.5 km/s). Low-aftershock seismicity on the supershear segment implies a simple and linear fault geometry there. An effort to monitor temporal seismic velocity changes across the ruptured area of the Northern Aegean earthquake is underway. In recent years, neighboring seismic broadband stations near active faults have been successfully used to detect such changes. The crosscorrelation functions (CCF) of ambient noise records between stations yields the corresponding traveltimes for those inter-station paths. Moreover, the auto-correlation functions (ACF) at each station produce the seismic responce for a coincident source and receiver position. Possible temporal changes of the measured traveltimes from CCFs and ACFs correspond to seismic velocity changes. Initially, we investigate the characteristics and sources of the ambient seismic noise as recorded at permanent seismic stations installed around NAT at the surrounding islands and in mainland Greece and Turkey. The microseismic noise levels show a clear seasonal variation at all stations. The noise levels across the double frequency band (DF; period range 4-8 s) reflect the local sea-weather conditions within a range of a few hundred kilometers. Three years of continuous seismic records framing the main shock have been analysed from ~15 stations within a radius of 100 km from the epicentre. We observe a clear decrease of seismic velocities most likely corresponding to the co-seismic shaking. The spatial variation of this velocity drop is imaged from all inter-station paths that correspond to CCF measurements and for station sites that correspond to ACF measurements. Thus, we explore a possible correlation between co

  19. Global climate change mitigation and sustainable forest management--The challenge of monitoring and verification

    Energy Technology Data Exchange (ETDEWEB)

    Makundi, Willy R.

    1997-12-31

    In this paper, sustainable forest management is discussed within the historical and theoretical framework of the sustainable development debate. The various criteria and indicators for sustainable forest management put forth by different institutions are critically explored. Specific types of climate change mitigation policies/projects in the forest sector are identified and examined in the light of the general criteria for sustainable forest management. Areas of compatibility and contradiction between the climate mitigation objectives and the minimum criteria for sustainable forest management are identified and discussed. Emphasis is put on the problems of monitoring and verifying carbon benefits associated with such projects given their impacts on pre-existing policy objectives on sustainable forest management. The implications of such policy interactions on assignment of carbon credits from forest projects under Joint Implementation/Activities Implemented Jointly initiatives are discussed. The paper concludes that a comprehensive monitoring and verification regime must include an impact assessment on the criteria covered under other agreements such as the Biodiversity and/or Desertification Conventions. The actual carbon credit assigned to a specific project should at least take into account the negative impacts on the criteria for sustainable forest management. The value of the impacts and/or the procedure to evaluate them need to be established by interested parties such as the Councils of the respective Conventions.

  20. Monitoring Change of Body Fluid during Physical Exercise using Bioimpedance Spectroscopy and Finite Element Simulations

    Directory of Open Access Journals (Sweden)

    Lisa Röthlingshöfer

    2011-12-01

    Full Text Available Athletes need a balanced body composition in order to achieve maximum performance. Especially dehydration reduces power and endurance during physical exercise. Monitoring the body composition, with a focus on body fluid, may help to avoid reduction in performance and other health problems.For this, a potential measurement method is bioimpedance spectroscopy (BIS. BIS is a simple, non-invasive measurement method that allows to determine different body compartments (body fluid, fat, fat-free mass. However, because many physiological changes occur during physical exercise that can influence impedance measurements and distort results, it cannot be assumed that the BIS data are related to body fluid loss alone.To confirm that BIS can detect body fluid loss due to physical exercise, finite element (FE simulations were done. Besides impedance, also the current density contribution during a BIS measurement was modeled to evaluate the influence of certain tissues on BIS measurements.Simulations were done using CST EM Studio (Computer Simulation Technology, Germany and the Visible Human Data Set (National Library of Medicine, USA. In addition to the simulations, BIS measurements were also made on athletes. Comparison between the measured bioimpedance data and simulation data, as well as body weight loss during sport, indicates that BIS measurements are sensitive enough to monitor body fluid loss during physical exercise.doi:10.5617/jeb.178 J Electr Bioimp, vol. 2, pp. 79-85, 2011

  1. Dynamic changes of microbial community diversity in a photohydrogen producing reactor monitored by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    YING Yanling; LV Zhenmei; MIN Hang; CHENG Jun

    2008-01-01

    A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which corresponded to different running periods of the reactor. The optimal hydrogen producing community formed on day 10. Using DGGE analysis with the pufM gene fragments was superior to V3-16S rDNA region genes for detecting the dynamic variations of the photosynthetic bacteria population during hydrogen production. The comparative sequence analysis of excised DGGE bands showed the relationship between specific population structures and system performance. Rhodopseudomonas palustris was presumed as one of the dominant community members for hydrogen production in the reactor. The PCR-DGGE protocol was proven to be a good tool for monitoring the photohydrogen production in real time and offered the available information to improve the photohydrogen producing system.

  2. Wireless Monitoring of Changes in Crew Relations during Long-Duration Mission Simulation.

    Directory of Open Access Journals (Sweden)

    Bernd Johannes

    Full Text Available Group structure and cohesion along with their changes over time play an important role in the success of missions where crew members spend prolonged periods of time under conditions of isolation and confinement. Therefore, an objective system for unobtrusive monitoring of crew cohesion and possible individual stress reactions is of high interest. For this purpose, an experimental wireless group structure (WLGS monitoring system integrated into a mobile psychophysiological system was developed. In the presented study the WLGS module was evaluated separately in six male subjects (27-38 years old participating in a 520-day simulated mission to Mars. Two days per week, each crew member wore a small sensor that registered the presence and distance of the sensors either worn by the other subjects or strategically placed throughout the isolation facility. The registration between two sensors was on average 91.0% in accordance. A correspondence of 95.7% with the survey video on day 475 confirmed external reliability. An integrated score of the "crew relation time index" was calculated and analyzed over time. Correlation analyses of a sociometric questionnaire (r = .35-.55, p< .05 and an ethological group approach (r = .45-.66, p < 05 provided initial evidence of the method's validity as a measure of cohesion when taking behavioral and activity patterns into account (e.g. only including activity phases in the afternoon. This confirms our assumption that the registered amount of time spent together during free time is associated with the intensity of personal relationships.

  3. Monitoring microcirculation changes in port wine stains during vascular targeted photodynamic therapy by laser speckle imaging.

    Science.gov (United States)

    Qiu, Haixia; Zhou, Yang; Gu, Ying; Ang, Qing; Zhao, ShiYong; Wang, Ying; Zeng, Jing; Huang, Naiyan

    2012-01-01

    This study was conducted to test laser speckle perfusion imaging (LSPI) for imaging microcirculation and monitoring microcirculatory changes of port wine stains (PWS) during vascular targeted photodynamic therapy (V-PDT). Before and 5 min after V-PDT, PWS lesions and the corresponding contralateral healthy skins of 24 PWS patients were scanned, whereas seven PWS patients were scanned throughout V-PDT. V-PDT was conducted immediately after intravenous injection of photocarcinorin (4-5 mg kg(-1)). A 532 nm laser was used for irradiation (power density: 80-100 mW cm(-2), exposure time: 20-50 min). Before V-PDT, all 24 PWS patients demonstrated a significant difference in perfusion between the PWS lesion and the contralateral healthy control skin (1132 ± 724 and 619 ± 478 PU, respectively, P 0.05). During V-PDT, the perfusion of seven PWS patients increased rapidly after initiation of V-PDT, reached a maximum within 10 min, lasted for several minutes, and slowly returned to a relatively lower level at the end of V-PDT. On the basis of these results, LSPI is capable of imaging PWS microvasculature and monitoring microvascular reactivity to V-PDT.

  4. Surface Emissivity Retrieved with Satellite Ultraspectral IR Measurements for Monitoring Global Change

    Science.gov (United States)

    Zhou, Daniel K.; Larar, Allen M.; Liu, Xu; Smith, William L.; Schluessel, Peter

    2009-01-01

    Surface and atmospheric thermodynamic parameters retrieved with advanced ultraspectral remote sensors aboard Earth observing satellites are critical to general atmospheric and Earth science research, climate monitoring, and weather prediction. Ultraspectral resolution infrared radiance obtained from nadir observations provide atmospheric, surface, and cloud information. Presented here is the global surface IR emissivity retrieved from Infrared Atmospheric Sounding Interferometer (IASI) measurements under "clear-sky" conditions. Fast radiative transfer models, applied to the cloud-free (or clouded) atmosphere, are used for atmospheric profile and surface parameter (or cloud parameter) retrieval. The inversion scheme, dealing with cloudy as well as cloud-free radiances observed with ultraspectral infrared sounders, has been developed to simultaneously retrieve atmospheric thermodynamic and surface (or cloud microphysical) parameters. Rapidly produced surface emissivity is initially evaluated through quality control checks on the retrievals of other impacted atmospheric and surface parameters. Surface emissivity and surface skin temperature from the current and future operational satellites can and will reveal critical information on the Earth s ecosystem and land surface type properties, which can be utilized as part of long-term monitoring for the Earth s environment and global climate change.

  5. Blood flow changes after unilateral carotid artery ligation monitored by optical coherence tomography

    Science.gov (United States)

    Ma, Yushu; Liang, Chengbo; Suo, Yanyan; Zhao, Yuqian; Wang, Yi; Xu, Tao; Wang, Ruikang; Ma, Zhenhe

    2016-03-01

    Unilateral carotid artery ligation which could induce adaptive improvement is a classic model that has been widely used to study pathology of ischemic disease. In those studies, blood flow is an important parameter to characterize the ischemia. Optical coherence tomography (OCT) is a powerful imaging modality which can provide depth resolved images in biological tissue with high spatial and temporal resolution. SPF rats was anesthetized with isoflurane and divided into two groups. In first group, bilateral carotid artery was surgically exposed, and then left carotid artery was ligated. Blood flow changes of the contralateral carotid artery was monitored using high speed spectral domain optical coherence tomography, including the absolute flow velocity and the flow volume. In the other group, skull window was opened at the ipsilateral cerebral cortex of ligation and blood supply of small artery was measured before and after the ligation. The measured results demonstrate the blood supply compensation process after unilateral carotid artery ligation. With the superiority of high resolution, OCT is an effective technology in monitoring results of carotid artery after ligation.

  6. Changes in the frequency of food intake among children and teenagers: monitoring in a reference service

    Directory of Open Access Journals (Sweden)

    Larissa Soares Mariz

    2013-07-01

    Full Text Available PURPOSE: to identify changes in the food intake patterns among overweight children and teenagers, treated at a reference medical centre. METHOD: the method used is that of a cohort study, between April 2010 and April 2011. A total of 109 children and teenagers, either obese or overweight, took part in the study. The population was divided into two subgroups depending on the permanence period (more than 6 months, and less than 6 months off the treatment. The chi-square test and logistic regression were carried out. RESULTS: the group which had been longer off the treatment tended to consume more soft drinks, pasta and fried foods, and less fruit and vegetables. The group with less time showed an improvement, with a reduction of consumption of soft drinks and other goodies. There was confirmation of an increased risk for consumption of soft drinks, pasta and goodies in general, as also detachment from the treatment in adolescence. CONCLUSIONS: The group with a longer period of monitoring has had a positive change in food intake frequency. The main contribution made by this study is that of showing that multiprofissional treatment, including some nursing care, is efficient in progressively changing the food intake of children and adolescents who are overweight.

  7. Automatic Detection Method of Behavior Change in Dam Monitor Instruments Cause by Earthquakes

    Directory of Open Access Journals (Sweden)

    Fernando Mucio Bando

    2016-02-01

    Full Text Available A hydroelectric power plant consists of a project of great relevance for the social and economic development of a country. However, this kind of construction demands extensive attention because the occurrence of unusual behavior on its structure may result in undesirable consequences. Seismic waves are some of the phenomena which demand attention of one in charge of a dam safety because once it happens can directly affect the structure behavior. The target of this work is to present a methodology to automatically detect which monitoring instruments have gone under any change in pattern and their measurements after the seism. The detection method proposed is based on a neuro/fuzzy/bayesian formulation which is divided in three steps. Firstly, a clustering of points in a time series is developed from a self-organizing Kohonen map. Afterwards a fuzzy set is built to transform the initial time series, with arbitrary distribution, into a new series with beta distribution probability and thus enable the detection of changing points through a Monte Carlo simulation via Markov chains. In order to demonstrate the efficiency of the proposal the methodology has been applied in time series generated by Itaipu power plant building structures measurement instruments, which showed little behavior change after the earthquake in Chile in 2010.

  8. Monitoring changes in seismic velocity related to an ongoing rapid inflation event at Okmok volcano, Alaska

    Science.gov (United States)

    Bennington, Ninfa; Haney, Matt; De Angelis, Silvio; Thurber, Clifford; Freymueller, Jeff

    2015-01-01

    Okmok is one of the most active volcanoes in the Aleutian Arc. In an effort to improve our ability to detect precursory activity leading to eruption at Okmok, we monitor a recent, and possibly ongoing, GPS-inferred rapid inflation event at the volcano using ambient noise interferometry (ANI). Applying this method, we identify changes in seismic velocity outside of Okmok’s caldera, which are related to the hydrologic cycle. Within the caldera, we observe decreases in seismic velocity that are associated with the GPS-inferred rapid inflation event. We also determine temporal changes in waveform decorrelation and show a continual increase in decorrelation rate over the time associated with the rapid inflation event. Themagnitude of relative velocity decreases and decorrelation rate increases are comparable to previous studies at Piton de la Fournaise that associate such changes with increased production of volatiles and/ormagmatic intrusion within the magma reservoir and associated opening of fractures and/or fissures. Notably, the largest decrease in relative velocity occurs along the intrastation path passing nearest to the center of the caldera. This observation, along with equal amplitude relative velocity decreases revealed via analysis of intracaldera autocorrelations, suggests that the inflation sourcemay be located approximately within the center of the caldera and represent recharge of shallow magma storage in this location. Importantly, there is a relative absence of seismicity associated with this and previous rapid inflation events at Okmok. Thus, these ANI results are the first seismic evidence of such rapid inflation at the volcano.

  9. Effect of urine pH changed by dietary intervention on uric acid clearance mechanism of pH-dependent excretion of urinary uric acid

    Directory of Open Access Journals (Sweden)

    Kanbara Aya

    2012-06-01

    food materials. Uric acid and excreted urine pH retained a linear relationship, as reported previously. Among the five factors which are associated with calculating clearances for both uric acid and creatinine, we identified a conspicuous difference between acidic and alkaline diets in the uric acid concentration in serum as well as in urine; uric acid in the serum was higher in the acidic group than in the alkaline group, while uric acid in the urine in the acidic group was lower than that in the alkaline group. These changes of uric acid in acidic urine and in serum were reflected in the reduction of its clearance. From these observations, it is considered that uric acid may be reabsorbed more actively in acidic urine than in alkaline urine. Conclusion We conclude that alkalization of urine by eating nutritionally well-designed alkaline -prone food is effective for removing uric acid from the body.

  10. PRODAN dual emission feature to monitor BHDC interfacial properties changes with the external organic solvent composition.

    Science.gov (United States)

    Agazzi, Federico M; Rodriguez, Javier; Falcone, R Dario; Silber, Juana J; Correa, N Mariano

    2013-03-19

    We have investigated the water/benzyl-n-hexadecyldimethylammonium chloride (BHDC)/n-heptane:benzene reverse micelles (RMs) interfaces properties using 6-propionyl-2-(N,N-dimethyl)aminonaphthalene, PRODAN, as molecular probe. We have used absorption and emission (steady-state and time-resolved) spectroscopy of PRODAN to monitor the changes in the RMs interface functionalities upon changing the external organic solvent blend. We demonstrate that PRODAN is a useful probe to investigate how the external solvent composition affects the micelle interface properties. Our results show that changes in the organic solvent composition in water/BHDC/n-heptane:benzene RMs have a dramatic effect on the photophysics of PRODAN. Thus, increasing the aliphatic solvent content over the aromatic one produces PRODAN partition and PRODAN intramolecular electron transfer (ICT) processes. Additionally, the water presence in these RMs makes the PRODAN ICT process favored with the consequent decreases in the LE emission intensity and a better definition of the charge transfer (CT) band. All this evidence suggests that the benzene molecules are expelled out of the interface, and the water-BHDC interactions are stronger with more presence of water molecules in the polar part of the interface. Thus, we demonstrate that a simple change in the composition of the external phase promotes remarkable changes in the RMs interface. Finally, the results obtained with PRODAN together with those reported in a previous work in our lab reveal that the external phase is important when trying to control the properties of RMs interface. It should be noted that the external phase itself, besides the surfactant and the polar solvent sequestrated, is a very important control variable that can play a key role if we consider smart application of these RMs systems.

  11. Monitoring urban growth and detecting land-cover changes on the Istanbul metropolitan area.

    Science.gov (United States)

    Geymen, Abdurrahman; Baz, Ibrahim

    2008-01-01

    Istanbul is the most populated city of Turkey with a population of around 10.58 M (2000) living on around 5,750 km2. In 1980, the population was only 4.7 M and then it has been more than doubled in only two decades. The population has been increasing as a result of mass immigration. An urbanization process continues and it causes serious increases in urban areas while decreasing the amount of green areas. This rapid, uncontrolled, and illegal urbanization accompanied by insufficient infrastructure has caused degradation of forest and barren lands in the metropolitan area, especially through the last two decades. The watershed basins inside the metropolitan area and the transportation network have accelerated the land-cover changes, which have negative impacts on water quality of the basins. Monitoring urban growth and land cover change will enable better management of this complex urban area by the Greater Istanbul Metropolitan Municipality (GIMM). A temporal assessment of land-cover changes of Istanbul has been documented in this study. The study mainly focuses on the acquisition and analysis of Landsat TM and Landsat GeoCover LC satellite images reflecting the significant land-cover changes between the years of 1990 and 2005. Raster data were converted to vector data and used in Geographic Information Systems (GIS). A database was created for Istanbul metropolitan area to plan, manage, and utilize statistical attribute data covering population, water, forest, industry, and topographic position. Consequently an overlay analysis was carried out and land use/cover changes through years have been detected for the case study area. The capability of Landsat images in determining the alterations in the macro form of the city are also discussed.

  12. Monitoring the elasticity changes of HeLa cells during mitosis by atomic force microscopy

    Science.gov (United States)

    Jiang, Ningcheng; Wang, Yuhua; Zeng, Jinshu; Ding, Xuemei; Xie, Shusen; Yang, Hongqin

    2016-10-01

    Cell mitosis plays a crucial role in cell life activity, which is one of the important phases in cell division cycle. During the mitosis, the cytoskeleton micro-structure of the cell changed and the biomechanical properties of the cell may vary depending upon different mitosis stages. In this study, the elasticity property of HeLa cells during mitosis was monitored by atomic force microscopy. Also, the actin filaments in different mitosis stages of the cells were observed by confocal imaging. Our results show that the cell in anaphase is stiffer than that in metaphase and telophase. Furthermore, lots of actin filaments gathered in cells' center area in anaphase, which contributes to the rigidity of the cell in this phase. Our findings demonstrate that the nano-biomechanics of living cells could provide a new index for characterizing cell physiological states.

  13. Monitoring changes in soil carbon resulting from intensive production, a non-traditional agricultural methodology.

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Brian P.

    2013-03-01

    New Mexico State University and a group of New Mexico farmers are evaluating an innovative agricultural technique they call Intensive Production (IP). In contrast to conventional agricultural practice, IP uses intercropping, green fallowing, application of soil amendments and soil microbial inocula to sequester carbon as plant biomass, resulting in improved soil quality. Sandia National Laboratories role was to identify a non-invasive, cost effective technology to monitor soil carbon changes. A technological review indicated that Laser Induced Breakdown Spectroscopy (LIBS) best met the farmers objectives. Sandia partnered with Los Alamos National Laboratory (LANL) to analyze farmers test plots using a portable LIBS developed at LANL. Real-time LIBS field sample analysis was conducted and grab samples were collected for laboratory comparison. The field and laboratory results correlated well implying the strong potential for LIBS as an economical field scale analytical tool for analysis of elements such as carbon, nitrogen, and phosphate.

  14. Changing guards: time to move beyond body mass index for population monitoring of excess adiposity.

    Science.gov (United States)

    Tanamas, S K; Lean, M E J; Combet, E; Vlassopoulos, A; Zimmet, P Z; Peeters, A

    2016-07-01

    With the obesity epidemic, and the effects of aging populations, human phenotypes have changed over two generations, possibly more dramatically than in other species previously. As obesity is an important and growing hazard for population health, we recommend a systematic evaluation of the optimal measure(s) for population-level excess body fat. Ideal measure(s) for monitoring body composition and obesity should be simple, as accurate and sensitive as possible, and provide good categorization of related health risks. Combinations of anthropometric markers or predictive equations may facilitate better use of anthropometric data than single measures to estimate body composition for populations. Here, we provide new evidence that increasing proportions of aging populations are at high health-risk according to waist circumference, but not body mass index (BMI), so continued use of BMI as the principal population-level measure substantially underestimates the health-burden from excess adiposity.

  15. Monitoring eruption activity using temporal stress changes at Mount Ontake volcano

    Science.gov (United States)

    Terakawa, Toshiko; Kato, Aitaro; Yamanaka, Yoshiko; Maeda, Yuta; Horikawa, Shinichiro; Matsuhiro, Kenjiro; Okuda, Takashi

    2016-01-01

    Volcanic activity is often accompanied by many small earthquakes. Earthquake focal mechanisms represent the fault orientation and slip direction, which are influenced by the stress field. Focal mechanisms of volcano-tectonic earthquakes provide information on the state of volcanoes via stresses. Here we demonstrate that quantitative evaluation of temporal stress changes beneath Mt. Ontake, Japan, using the misfit angles of focal mechanism solutions to the regional stress field, is effective for eruption monitoring. The moving average of misfit angles indicates that during the precursory period the local stress field beneath Mt. Ontake was deviated from the regional stress field, presumably by stress perturbations caused by the inflation of magmatic/hydrothermal fluids, which was removed immediately after the expulsion of volcanic ejecta. The deviation of the local stress field can be an indicator of increases in volcanic activity. The proposed method may contribute to the mitigation of volcanic hazards. PMID:26892716

  16. Using oblique digital photography for alluvial sandbar monitoring and low-cost change detection

    Science.gov (United States)

    Tusso, Robert B.; Buscombe, Daniel D.; Grams, Paul E.

    2015-01-01

    The maintenance of alluvial sandbars is a longstanding management interest along the Colorado River in Grand Canyon. Resource managers are interested in both the long-term trend in sandbar condition and the short-term response to management actions, such as intentional controlled floods released from Glen Canyon Dam. Long-term monitoring is accomplished at a range of scales, by a combination of annual topographic survey at selected sites, daily collection of images from those sites using novel, autonomously operating, digital camera systems (hereafter referred to as 'remote cameras'), and quadrennial remote sensing of sandbars canyonwide. In this paper, we present results from the remote camera images for daily changes in sandbar topography.

  17. Monitoring eruption activity using temporal stress changes at Mount Ontake volcano.

    Science.gov (United States)

    Terakawa, Toshiko; Kato, Aitaro; Yamanaka, Yoshiko; Maeda, Yuta; Horikawa, Shinichiro; Matsuhiro, Kenjiro; Okuda, Takashi

    2016-02-19

    Volcanic activity is often accompanied by many small earthquakes. Earthquake focal mechanisms represent the fault orientation and slip direction, which are influenced by the stress field. Focal mechanisms of volcano-tectonic earthquakes provide information on the state of volcanoes via stresses. Here we demonstrate that quantitative evaluation of temporal stress changes beneath Mt. Ontake, Japan, using the misfit angles of focal mechanism solutions to the regional stress field, is effective for eruption monitoring. The moving average of misfit angles indicates that during the precursory period the local stress field beneath Mt. Ontake was deviated from the regional stress field, presumably by stress perturbations caused by the inflation of magmatic/hydrothermal fluids, which was removed immediately after the expulsion of volcanic ejecta. The deviation of the local stress field can be an indicator of increases in volcanic activity. The proposed method may contribute to the mitigation of volcanic hazards.

  18. Using serological measures to monitor changes in malaria transmission in Vanuatu

    Directory of Open Access Journals (Sweden)

    Clements Archie

    2010-06-01

    Full Text Available Abstract Background With renewed interest in malaria elimination, island environments present unique opportunities to achieve this goal. However, as transmission decreases, monitoring and evaluation programmes need increasingly sensitive tools to assess Plasmodium falciparum and Plasmodium vivax exposure. In 2009, to assess the role of serological markers in evaluating malaria transmission, a cross-sectional seroprevalence study was carried out in Tanna and Aneityum, two of the southernmost islands of the Vanuatu archipelago, areas where malaria transmission has been variably reduced over the past few decades. Methods Malaria transmission was assessed using serological markers for exposure to P. falciparum and P. vivax. Filter blood spot papers were collected from 1,249 people from Tanna, and 517 people from Aneityum to assess the prevalence of antibodies to two P. falciparum antigens (MSP-119 and AMA-1 and two P. vivax antigens (MSP-119 and AMA-1. Age-specific prevalence was modelled using a simple catalytic conversion model based on maximum likelihood to generate a community seroconversion rate (SCR. Results Overall seropositivity in Tanna was 9.4%, 12.4% and 16.6% to P. falciparum MSP-119, AMA-1 and Schizont Extract respectively and 12.6% and 15.0% to P. vivax MSP-119 and AMA-1 respectively. Serological results distinguished between areas of differential dominance of either P. vivax or P. falciparum and analysis of age-stratified results showed a step in seroprevalence occurring approximately 30 years ago on both islands, indicative of a change in transmission intensity at this time. Results from Aneityum suggest that several children may have been exposed to malaria since the 2002 P. vivax epidemic. Conclusion Seroepidemiology can provide key information on malaria transmission for control programmes, when parasite rates are low. As Vanuatu moves closer to malaria elimination, monitoring changes in transmission intensity and identification

  19. Estudo prospectivo comparativo de duas modalidades de posicionamento do sensor de phmetria esofágica prolongada: por manometria esofágica e pela viragem do Ph Comparative prospective study of two positioning modes of 24-hour esophageal pH monitoring: by esophageal manometry and by the pH step-up technique

    Directory of Open Access Journals (Sweden)

    Ary Nasi

    2008-12-01

    Full Text Available RACIONAL: Por padronização aceita internacionalmente, posiciona-se o sensor distal de pHmetria esofágica a 5 cm acima da borda superior do esfíncter inferior do esôfago, localizado por manometria esofágica. Porém, vários autores sugerem técnicas alternativas de posicionamento que prescindem da manometria. Dentre essas, destaca-se a da viragem do pH, tema este controverso pela sua duvidosa confiabilidade. OBJETIVO: Avaliar a adequação do posicionamento do sensor distal de pHmetria pela técnica de viragem do pH, considerando-se a presença, o tipo e o grau de erro de posicionamento que tal técnica proporciona, e também estudar a influência da posição adotada pelo paciente durante a técnica da viragem. MÉTODOS: Foram estudados de modo prospectivo, durante o período de 1 ano, 1.031 pacientes. Durante entrevista clínica, foram registrados os dados demográficos e as queixas clínicas apresentadas. Todos foram submetidos a manometria esofágica para localização do esfíncter inferior do esôfago e a técnica da viragem do pH. A identificação do ponto de viragem foi realizada de dois modos distintos, caracterizando dois grupos de estudo: com o paciente sentado (grupo I - 450 pacientes e com o paciente em decúbito dorsal horizontal (grupo II - 581 pacientes. Após a identificação do ponto de viragem, o sensor distal de pHmetria era posicionado na posição padronizada, baseada na localização manométrica do esfíncter. Registrava-se onde seria posicionado o sensor de pH se fosse adotada a técnica da viragem. Para avaliação da adequação do posicionamento, considerou-se que o erro é representado pela diferença (em centímetros entre a localização padronizada (manométrica e a localização que seria adotada caso fosse empregada a técnica da viragem. Considerou-se que o erro seria grosseiro se fosse maior que 2 cm. Analisou-se também o tipo de erro mais freqüente (se acima ou abaixo da posição padronizada. Foram

  20. Investigation of vertical mass changes in the south of Izmir (Turkey) by monitoring microgravity and GPS/GNSS methods

    Indian Academy of Sciences (India)

    Oya Pamukçu; Tolga Gönenç; Ayça Çirmik; Petek Sindirgi; İlknur Kaftan; Özer Akdemir

    2015-02-01

    The monitoring of gravity changes in a region enables the investigation of regional structural elements depending upon the changes in load compensation. This method, preferred in recent years, has yielded good results from different parts of the world for determination of the deformation at fields. With the addition of GPS/GNSS monitoring to microgravity studies, the mass changes within the crust in vertical directional movements of a region can be estimated. During GPS/GNSS monitoring and microgravity studies, it was found that the behaviour of vertical directions of Izmir and the surrounding areas, indicate an active tectonic regime and high seismic activity, especially since 2000. As a result, regions considered to have a mass change in vertical direction were determined by 3-year measurements and it was found that they were consistently highly seismic.

  1. Electron paramagnetic resonance-based pH mapping using spectral-spatial imaging of sequentially scanned spectra

    OpenAIRE

    Koda, Shunichi; Goodwin, Jonathan; Khramtsov, Valery V.; Fujii, Hirotada; Hirata, Hiroshi

    2012-01-01

    The development of electron paramagnetic resonance (EPR)-based mapping of pH is an important advancement for the field of diagnostic imaging. The ability to accurately quantify pH change in vivo and monitor spatial distribution is desirable for the assessment of a number of pathological conditions in the human body as well as the monitoring of treatment response. In this work we introduce a method for EPR-based pH mapping, utilizing a method of spectral-spatial imaging of sequentially scanned...

  2. Shifting Restoration Policy to Address Landscape Change, Novel Ecosystems, and Monitoring

    Directory of Open Access Journals (Sweden)

    Joy B. Zedler

    2012-12-01

    Full Text Available Policy to guide ecological restoration needs to aim toward minimizing the causes of ecosystem degradation; where causes cannot be eliminated or minimized, policy needs to shift toward accommodating irreversible landscape alterations brought about by climate change, nitrogen deposition, altered hydrology, degraded soil, and declining biodiversity. The degree to which lost diversity and ecosystem services can be recovered depends on the extent and nature of landscape change. For wetlands that occur at the base of watersheds that have been developed for agriculture or urban centers, the inflows of excess water, sediment, and nutrients can be permanent and can severely challenge efforts to restore historical services, including biodiversity support. In such cases, the historical state of downstream wetlands will not be completely restorable. Wetland restoration policy should promote watershed planning, wherein wetland and upland restoration is prioritized to achieve multiple, specific ecosystem services. For downstream wetlands, it is realistic to aim to enhance nitrogen removal and to establish native plants that are matrix dominants, namely, those that facilitate rather than displace other natives. More ambitious objectives such as maximizing diversity would be suitable for less-altered, upstream wetlands. Policy should also call for adaptive restoration and long-term assessments. For large sites and multiple sites of a given wetland type within a region, experimental tests can determine a wetland's ability to support high levels of ecosystem services. Once projects are underway, long-term monitoring of structural and functional indicators can characterize progress toward each objective. Managers can then learn which targets are unachievable based on data, not just opinion. Where an experimental treatment shows limited progress, practitioners would shift to more promising treatments and targets, thereby adapting restoration efforts to changing

  3. Drones as tools for monitoring beach topography changes in the Ligurian Sea (NW Mediterranean)

    Science.gov (United States)

    Casella, Elisa; Rovere, Alessio; Pedroncini, Andrea; Stark, Colin P.; Casella, Marco; Ferrari, Marco; Firpo, Marco

    2016-04-01

    The aim of this study was to evaluate topographic changes along a stretch of coastline in the Municipality of Borghetto Santo Spirito (Region of Liguria, Italy, north-western Mediterranean) by means of a remotely piloted aircraft system coupled with structure from motion and multi-view stereo techniques. This sector was surveyed three times over 5 months in the fall-winter of 2013-2014 (1 November 2013, 4 December 2013, 17 March 2014) to obtain digital elevation models and orthophotos of the beach. Changes in beach topography associated with storm action and human activities were assessed in terms of gain/loss of sediments and shifting of the wet-dry boundary defining the shoreline. Between the first and second surveys, the study area was hit by two storms (10-11 November 2013 and 21-22 November 2013) with waves approaching from the E-NNE, causing a shoreline retreat which, in some sectors, reached 7 m. Between the second and third surveys, by contrast, four storms (25-27 December 2013, 5-6 January 2014, 17-18 January 2014 and 6-10 February 2014) with waves propagating from the SE produced a general advancement of the shoreline (up to ~5 m) by deposition of sediments along some parts of the beach. The data also reflect changes in beach topography due to human activity during the 2013 fall season, when private beach managers quarried ~178 m3 of sediments on the emerged beach near the shoreline to accumulate them landwards. The results show that drones can be used for regular beach monitoring activities, and that they can provide new insights into the processes related to natural and/or human-related topographic beach changes.

  4. Muscle pH and temperature changes in hot- and cold-deboned ostrich (Struthio camelus var. domesticus) Muscularis gastrocnemius, pars interna and Muscularis iliofibularis during the first 23h post-mortem.

    Science.gov (United States)

    Hoffman, L C; Botha, Suné St C; Britz, T J

    2007-02-01

    Cold-shortening is the response when muscles are exposed to temperatures below 10°C with a pH>6.20. The course of pH within hot-deboned and intact ostrich M. gastrocnemius, pars interna and M. iliofibularis were followed for the first 23-24h post-mortem to investigate the changes in pH as well as to determine the point of minimum pH for ostrich muscles post-mortem. The hot-deboned muscles took longer to reach the point of minimum pH than the intact muscles. There was no significant (P=0.4508) difference in the minimum pH (5.91±0.26) between the hot-deboned and the intact muscles. It was concluded that both the M. gastrocnemius, pars interna and the M. iliofibularis reached a pHmuscle temperatures above 10°C; and therefore showed no risk of cold-shortening if these muscles were to be hot-deboned 2-4h post-mortem.

  5. Electroencephalographic Patterns Recorded by Continuous EEG Monitoring in Patients with Change of Consciousness in the Neurological Intensive Care Unit.

    Science.gov (United States)

    Altindağ, Ebru; Okudan, Zeynep Vildan; Tavukçu Özkan, Sedef; Krespi, Yakup; Baykan, Betül

    2017-06-01

    Our aim was to examine the frequency of various electrographic patterns including periodic discharges (PD), repetitive spike waves (RSW), rhythmic delta activities (RDA), nonconvulsive seizures (NCS) and nonconvulsive status epilepticus (NCSE) in continuous EEG monitoring (cEEG) of the critically ill patients with change of consciousness and the presence of specific clinical and laboratory findings associated with these important patterns in this study. Patients with changes of consciousness in the neurological intensive care unit (NICU) were consecutively monitored with cEEG during 2 years. Their clinical, electrophysiological, radiological and laboratory findings were evaluated retrospectively. This sample consisted of 57 (25 men) patients with a mean age of 68.2 years. Mean duration of cEEG monitoring was 2532.6 minutes. The most common electrographic patterns were PD (33%) and NCS-NCSE (26.3%). The presence of NCS-NCSE was significantly associated with PD (57.9%, p<0.001). PD and NCS-NCSE were the mostly seen in patients with acute stroke and hypoxic encephalopathy. Duration of monitoring was significantly longer in the group with PD and NCS-NCSE (p:0.004, p:0.014). Detection of any electrographic pattern in EEG before monitoring was associated with the presence of any pattern in cEEG (59.3%, p<0.0001). Convulsive or nonconvulsive seizure during monitoring was common in patients with electrographic patterns (p<0.0001). 66.7% of NCS-NCSE was seen within the first 12 hours and 26.7% was seen within the 12-24 hours of the monitoring. Detection of any electrographic pattern in EEG before monitoring was associated with the presence of any important pattern in cEEG monitoring. This association suggest that at least 24 hours-monitoring of these patients could be useful for the diagnosis of clinical and/or electrographic seizures.

  6. Neuronal pH regulation

    DEFF Research Database (Denmark)

    Vorstrup, S; Jensen, K E; Thomsen, C

    1989-01-01

    The intracellular pH in the brain was studied in six healthy volunteers before and immediately after the administration of 2 g of acetazolamide. Phosphorus-31 nuclear magnetic resonance spectroscopy by a 1.5 tesla whole-body scanner was used. The chemical shift between the inorganic phosphate...... and the phosphocreatine resonance frequencies was used for indirect assessment of the intracellular pH. The mean baseline intracellular pH was 7.05 +/- 0.04 (SD). The mean pH changes obtained at 15-min intervals within the first hour of acetazolamide administration were -0.03 +/- 0.04 (SD), -0.02 +/- 0.03 (SD), and 0.......00 +/- 0.04 (SD), i.e., no statistically significant pH decrease was observed during the period where extracellular pH is known to drop markedly. Although several factors contribute to the lack of change of the intraneuronal pH, we will discuss that this observation in addition might suggest a direct...

  7. An innovative procedure for monitoring the change in soil seismic response by InSAR data:

    Science.gov (United States)

    Albano, Matteo; Polcari, Marco; Bignami, Christian; Moro, Marco; Saroli, Michele; Stramondo, Salvatore

    2016-12-01

    We developed an empirical procedure to evaluate the effect of the ground subsidence on the spatial and temporal seismic response of soils. The proposed method exploits the capabilities of the spaceborne SAR Interferometry technique to detect and map the ground subsidence with unprecedented spatial and temporal coverage. The information provided by satellites is combined with a-priori geological/geotechnical information to assess the soil compaction and the shortening of the soil vibration periods. The procedure was applied to estimate the shortening of the soil resonant period of Mexico City between 2005 and 2013. The results show that in approximately nine years the ground surface has subsided by approximately 0.5⿿3.5 m and the soil resonant period has decreased by approximately 0.1⿿0.4 s. The obtained results, validated with field measurements, highlight the effectiveness of the proposed procedure for the continuous monitoring of the soil resonant periods. The estimated change in resonant period on Mexico City has a great impact on the response spectra used for design, it is then necessary to update the map of the soil resonant period in order to account for the change of dynamic properties of soils caused by subsidence.

  8. Sequential change detection and monitoring of temporal trends in random-effects meta-analysis.

    Science.gov (United States)

    Dogo, Samson Henry; Clark, Allan; Kulinskaya, Elena

    2016-12-08

    Temporal changes in magnitude of effect sizes reported in many areas of research are a threat to the credibility of the results and conclusions of meta-analysis. Numerous sequential methods for meta-analysis have been proposed to detect changes and monitor trends in effect sizes so that meta-analysis can be updated when necessary and interpreted based on the time it was conducted. The difficulties of sequential meta-analysis under the random-effects model are caused by dependencies in increments introduced by the estimation of the heterogeneity parameter τ(2) . In this paper, we propose the use of a retrospective cumulative sum (CUSUM)-type test with bootstrap critical values. This method allows retrospective analysis of the past trajectory of cumulative effects in random-effects meta-analysis and its visualization on a chart similar to CUSUM chart. Simulation results show that the new method demonstrates good control of Type I error regardless of the number or size of the studies and the amount of heterogeneity. Application of the new method is illustrated on two examples of medical meta-analyses. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd.

  9. Ribosomal intergenic spacer analysis as a tool for monitoring methanogenic Archaea changes in an anaerobic digester.

    Science.gov (United States)

    Ciesielski, Slawomir; Bułkowska, Katarzyna; Dabrowska, Dorota; Kaczmarczyk, Dariusz; Kowal, Przemyslaw; Możejko, Justyna

    2013-08-01

    The applicability of a newly-designed PCR primer pair in examination of methanogenic Archaea in a digester treating plant biomass was evaluated by Ribosmal Intergenic Spacer Analysis (RISA). To find a suitable approach, three variants of RISA were tested: (1) standard, polyacrylamide gel-based, (2) automated, utilized capillary electrophoresis (GA-ARISA), and (3) automated microfluidics-based (MF-ARISA). All three techniques yielded a consistent picture of archaeal community structure changes during anaerobic digestion monitored for more than 6 weeks. While automated variants were more practical for handling and rapid analysis of methanogenic Archaea, the gel-based technique was advantageous when micro-organism identification was required. A DNA-sequence analysis of dominant bands extracted from the gel revealed that the main role in methane synthesis was played by micro-organisms affiliated with Methanosarcina barkeri. The obtained results revealed that RISA is a robust method allowing for detailed analysis of archaeal community structure during organic biomass conversion into biogas. In addition, our results showed that GA-ARISA has a higher resolution and reproducibility than other variants of RISA and could be used as a technique for tracking changes in methanogenic Archaea in an anaerobic digester.

  10. Monitored landscape change of Lake Baiyangdian wetland with dynamic reed area based on remote sensing

    Science.gov (United States)

    Wang, Zhen; He, Lei; Zhang, Shengwei; Lei, Yuping

    2009-09-01

    Lake Baiyangdian, a largest wetland ecosystem in North China Plain, has dried up on seven occasions since the 1960s. In recent years, more than one billion of cubic meters of water from upstream reservoirs and Yellow river have been transported to the lake to rescue the shrinking wetlands. Since the Lake Baiyangdian was actually composed of 143 small lakes and more than 70 villages with large or small area of cropland, dynamic distribution of aquatic plants in wetland such as reed and associated growth condition of these allowed to monitor the changes of wetland landscape and water quality to support the policy applications of water conveyance and wetland environmental treatment and control. Assisted with ground survey analyses and Landsat TM image, the MODIS 250 m time series Normalized Difference Vegetation Index (NDVI), given its combination of medium spatial and high temporal resolution, were applied to detect the unique rapid growth stage of reed in the spring from adjacent crops such as winter wheat, cotton, and spring maize, of which has a similar phenology in development of leaf area index, and dynamic reed areas were mapped in recent decade. Landscape changes of the wetland were analyzed using maps of reed area and hydrological data.

  11. Multivariate DPOAE metrics for identifying changes in hearing: Perspectives from ototoxicity monitoring

    Science.gov (United States)

    Konrad-Martin, Dawn; Reavis, Kelly M.; McMillan, Garnett P.; Dille, Marilyn F.

    2017-01-01

    Distortion-product otoacoustic emissions (DPOAEs) provide a window into real-time cochlear mechanical function. Yet, relationships between the changes in DPOAE metrics and auditory sensitivity are still poorly understood. Explicating these relationships might support the use of DPOAEs in hearing conservation programs (HCPs) for detecting early damage leading to noise-induced hearing loss (NIHL) so that mitigating steps might be taken to limit any lasting damage. This report describes the development of DPOAE-based statistical models to assess the risk of hearing loss from cisplatin treatment among cancer patients. Ototoxicity risk assessment (ORA) models were constructed using a machine learning paradigm in which partial least squares and leave-one-out cross-validation were applied, yielding optimal screening algorithms from a set of known risk factors for ototoxicity and DPOAE changes from pre-exposure baseline measures. Single DPOAE metrics alone were poorer indicators of the risk of ototoxic hearing shifts than the best performing multivariate models. This finding suggests that multivariate approaches applied to the use of DPOAEs in a HCP, will improve the ability of DPOAE measures to identify ears with noise-induced mechanical damage and/or hearing loss at each monitoring interval. This prediction must be empirically assessed in noise-exposed subjects. PMID:22264063

  12. Sequential change detection and monitoring of temporal trends in random‐effects meta‐analysis

    Science.gov (United States)

    Dogo, Samson Henry; Clark, Allan

    2016-01-01

    Temporal changes in magnitude of effect sizes reported in many areas of research are a threat to the credibility of the results and conclusions of meta‐analysis. Numerous sequential methods for meta‐analysis have been proposed to detect changes and monitor trends in effect sizes so that meta‐analysis can be updated when necessary and interpreted based on the time it was conducted. The difficulties of sequential meta‐analysis under the random‐effects model are caused by dependencies in increments introduced by the estimation of the heterogeneity parameter τ 2. In this paper, we propose the use of a retrospective cumulative sum (CUSUM)‐type test with bootstrap critical values. This method allows retrospective analysis of the past trajectory of cumulative effects in random‐effects meta‐analysis and its visualization on a chart similar to CUSUM chart. Simulation results show that the new method demonstrates good control of Type I error regardless of the number or size of the studies and the amount of heterogeneity. Application of the new method is illustrated on two examples of medical meta‐analyses. © 2016 The Authors. Research Synthesis Methods published by John Wiley & Sons Ltd. PMID:27933728

  13. Monitoring landscape change for LANDFIRE using multi-temporal satellite imagery and ancillary data

    Science.gov (United States)

    Vogelmann, James E.; Kost, Jay R.; Tolk, Brian; Howard, Stephen M.; Short, Karen; Chen, Xuexia; Huang, Chengquan; Pabst, Kari; Rollins, Matthew G.

    2011-01-01

    LANDFIRE is a large interagency project designed to provide nationwide spatial data for fire management applications. As part of the effort, many 2000 vintage Landsat Thematic Mapper and Enhanced Thematic Mapper plus data sets were used in conjunction with a large volume of field information to generate detailed vegetation type and structure data sets for the entire United States. In order to keep these data sets current and relevant to resource managers, there was strong need to develop an approach for updating these products. We are using three different approaches for these purposes. These include: 1) updating using Landsat-derived historic and current fire burn information derived from the Monitoring Trends in Burn Severity project; 2) incorporating vegetation disturbance information derived from time series Landsat data analysis using the Vegetation Change Tracker; and 3) developing data products that capture subtle intra-state disturbance such as those related to insects and disease using either Landsat or the Moderate Resolution Imaging Spectroradiometer (MODIS). While no one single approach provides all of the land cover change and update information required, we believe that a combination of all three captures most of the disturbance conditions taking place that have relevance to the fire community.

  14. The monitoring evaluation, reporting and verification of climate change mitigation projects

    Energy Technology Data Exchange (ETDEWEB)

    Vine, E.; Sathaye, J.

    1998-05-01

    Because of concerns with the growing threat of global climate change from increasing emissions of greenhouse gases, the US and other countries are implementing, by themselves or in cooperation with one or more other nations, climate change mitigation projects. These projects will reduce greenhouse gas (GHG) emissions or sequester carbon, and will also result in non-GHG benefits (i.e., environmental, economic, and social benefits). Monitoring, evaluating, reporting, and verifying (MERV) guidelines are needed for these projects to accurately determine their net GHG, and other, benefits. Implementation of MERV guidelines is also intended to: (1) increase the reliability of data for estimating GHG benefits; (2) provide real-time data so that mid-course corrections can be made; (3) introduce consistency and transparency across project types and reporters; and (4) enhance the credibility of the projects with stakeholders. In this paper, the authors review the issues involved in MERV activities. They identify several topics that future protocols and guidelines need to address, such as: (1) establishing a credible baseline; (2) accounting for impacts outside project boundaries through leakage; (3) net GHG reductions and other benefits; (4) precision of measurement; (5) MERV frequency; (6) persistence (sustainability) of savings, emissions reduction, and carbon sequestration; (7) reporting by multiple project participants; (8) verification of GHG reduction credits; (9) uncertainty and risk; (10) institutional capacity in conducting MERV; and (11) the cost of MERV.

  15. e-phenology: monitoring leaf phenology and tracking climate changes in the tropics

    Science.gov (United States)

    Morellato, Patrícia; Alberton, Bruna; Almeida, Jurandy; Alex, Jefersson; Mariano, Greice; Torres, Ricardo

    2014-05-01

    The e-phenology is a multidisciplinary project combining research in Computer Science and Phenology. Its goal is to attack theoretical and practical problems involving the use of new technologies for remote phenological observation aiming to detect local environmental changes. It is geared towards three objectives: (a) the use of new technologies of environmental monitoring based on remote phenology monitoring systems; (b) creation of a protocol for a Brazilian long term phenology monitoring program and for the integration across disciplines, advancing our knowledge of seasonal responses within tropics to climate change; and (c) provide models, methods and algorithms to support management, integration and analysis of data of remote phenology systems. The research team is composed by computer scientists and biology researchers in Phenology. Our first results include: Phenology towers - We set up the first phenology tower in our core cerrado-savanna 1 study site at Itirapina, São Paulo, Brazil. The tower received a complete climatic station and a digital camera. The digital camera is set up to take daily sequence of images (five images per hour, from 6:00 to 18:00 h). We set up similar phenology towers with climatic station and cameras in five more sites: cerrado-savanna 2 (Pé de Gigante, SP), cerrado grassland 3 (Itirapina, SP), rupestrian fields 4 ( Serra do Cipo, MG), seasonal forest 5 (Angatuba, SP) and Atlantic raiforest 6 (Santa Virginia, SP). Phenology database - We finished modeling and validation of a phenology database that stores ground phenology and near-remote phenology, and we are carrying out the implementation with data ingestion. Remote phenology and image processing - We performed the first analyses of the cerrado sites 1 to 4 phenology derived from digital images. Analysis were conducted by extracting color information (RGB Red, Green and Blue color channels) from selected parts of the image named regions of interest (ROI). using the green color

  16. MONITORING TREE POPULATION DYNAMICS IN ARID ZONE THROUGH MULTIPLE TEMPORAL SCALES: INTEGRATION OF SPATIAL ANALYSIS, CHANGE DETECTION AND FIELD LONG TERM MONITORING

    Directory of Open Access Journals (Sweden)

    S. Isaacson

    2016-06-01

    Full Text Available High mortality rates and lack of recruitment in the acacia populations throughout the Negev Desert and the Arava rift valley of Israel have been reported in previous studies. However, it is difficult to determine whether these reports can be evidence to a significant decline trend of the trees populations. This is because of the slow dynamic processes of acaia tree populations and the lack of long term continuous monitoring data. We suggest a new data analysis technique that expands the time scope of the field long term monitoring of trees in arid environments. This will enables us to improve our understanding of the spatial and temporal changes of these populations. We implemented two different approaches in order to expand the time scope of the acacia population field survey: (1 individual based tree change detection using Corona satellite images and (2 spatial analysis of trees population, converting spatial data into temporal data. The next step was to integrate the results of the two analysis techniques (change detection and spatial analysis with field monitoring. This technique can be implemented to other tree populations in arid environments to help assess the vegetation conditions and dynamics of those ecosystems.

  17. Ph3CCOOSnPh3.Ph3PO AND Ph3CCOOSnPh3.Ph3AsO: SYNTHESIS AND INFRARED STUDY

    Directory of Open Access Journals (Sweden)

    ABDOU MBAYE

    2014-08-01

    Full Text Available The mixture of ethanolic solutions of Ph3CCOOSnPh3 and Ph3PO or Ph3AsO gives Ph3CCOOSnPh3.Ph3PO and Ph3CCOOSnPh3.Ph3AsO adducts which have been characterized by infrared spectroscopy. A discrete structure is suggested for both, the environment around the tin centre being trigonal bipyramidal, the triphenylacetate anion behaving as a mondentate ligand.

  18. Monitoring Changes in Water Resources Systems Using High Resolution Satellite Observations: Application to Lake Urmia

    Science.gov (United States)

    Norouzi, H.; AghaKouchak, A.; Madani, K.; Mirchi, A.; Farahmand, A.; Conway, C.

    2013-12-01

    Lake Urmia with its unique ecosystem in northwestern Iran is the second largest saltwater lake in the world. It is home of more than 300 species of birds, reptiles, and mammals with high salinity level of more than 300 g/l. In recent years, a significant water retreat has occurred in this lake. In this study, we tried to monitor the desiccation of the lake over more than four decades using remote sensing observations. Multi-spectral high-resolution LandSat images of the Lake Urmia region from 1972 to 2012 were acquired to derive the lake area. The composite maps of the lake were created, and a Bayesian Maximum Likelihood classification technique was used to classify land and water in the composite maps. The time series of the lake area reveals that it has shrunk by more than 40% in the past ten years. Moreover, water budget related components such as precipitation, soil moisture, and drought indices from remote sensing of the lake basin were utilized to investigate if droughts or climate change are the primary driving forces behind this phenomenon. These analyses show that the retreat of the lake is not related to droughts or global climate change as it has survived several drought events before year 2000. Similar analyses conducted on Lake Van located about 400 km west of Lake Urmia with very similar climate pattern revealed no significant areal change despite the lake's exposure to similar drought events. These results raise serious concern about the destructive role of unbridled development coupled with supply-oriented water management scheme driven by a classic upstream-downstream competition for water in the Lake Urmia region. There is an urgent need to investigate sustainable restoration initiatives for Lake Urmia in order to prevent an environmental disaster comparable to catastrophic death of Aral Sea.

  19. PhEDEx Data Service

    Science.gov (United States)

    Egeland, Ricky; Wildish, Tony; Huang, Chih-Hao

    2010-04-01

    The PhEDEx Data Service provides access to information from the central PhEDEx database, as well as certificate-authenticated managerial operations such as requesting the transfer or deletion of data. The Data Service is integrated with the "SiteDB" service for fine-grained access control, providing a safe and secure environment for operations. A plug-in architecture allows server-side modules to be developed rapidly and easily by anyone familiar with the schema, and can automatically return the data in a variety of formats for use by different client technologies. Using HTTP access via the Data Service instead of direct database connections makes it possible to build monitoring web-pages with complex drill-down operations, suitable for debugging or presentation from many aspects. This will form the basis of the new PhEDEx website in the near future, as well as providing access to PhEDEx information and certificate-authenticated services for other CMS dataflow and workflow management tools such as CRAB, WMCore, DBS and the dashboard. A PhEDEx command-line client tool provides one-stop access to all the functions of the PhEDEx Data Service interactively, for use in simple scripts that do not access the service directly. The client tool provides certificate-authenticated access to managerial functions, so all the functions of the PhEDEx Data Service are available to it. The tool can be expanded by plug-ins which can combine or extend the client-side manipulation of data from the Data Service, providing a powerful environment for manipulating data within PhEDEx.

  20. PhEDEx Data Service

    Energy Technology Data Exchange (ETDEWEB)

    Egeland, Ricky [University of Minnesota, Twin Cities (United States); Wildish, Tony [Princeton University (United States); Huang, Chih-Hao [Fermi National Accelerator Laboratory (United States)

    2010-04-01

    The PhEDEx Data Service provides access to information from the central PhEDEx database, as well as certificate-authenticated managerial operations such as requesting the transfer or deletion of data. The Data Service is integrated with the 'SiteDB' service for fine-grained access control, providing a safe and secure environment for operations. A plug-in architecture allows server-side modules to be developed rapidly and easily by anyone familiar with the schema, and can automatically return the data in a variety of formats for use by different client technologies. Using HTTP access via the Data Service instead of direct database connections makes it possible to build monitoring web-pages with complex drill-down operations, suitable for debugging or presentation from many aspects. This will form the basis of the new PhEDEx website in the near future, as well as providing access to PhEDEx information and certificate-authenticated services for other CMS dataflow and workflow management tools such as CRAB, WMCore, DBS and the dashboard. A PhEDEx command-line client tool provides one-stop access to all the functions of the PhEDEx Data Service interactively, for use in simple scripts that do not access the service directly. The client tool provides certificate-authenticated access to managerial functions, so all the functions of the PhEDEx Data Service are available to it. The tool can be expanded by plug-ins which can combine or extend the client-side manipulation of data from the Data Service, providing a powerful environment for manipulating data within PhEDEx.

  1. BACE1 in the retina: a sensitive biomarker for monitoring early pathological changes in Alzheimer's disease.

    Science.gov (United States)

    Li, Lan; Luo, Jia; Chen, Dan; Tong, Jian-Bin; Zeng, Le-Ping; Cao, Yan-Qun; Xiang, Jian; Luo, Xue-Gang; Shi, Jing-Ming; Wang, Hui; Huang, Ju-Fang

    2016-03-01

    Because of a lack of sensitive biomarkers, the diagnosis of Alzheimer's disease (AD) cannot be made prior to symptom manifestation. Therefore, it is crucial to identify novel biomarkers for the presymptomatic diagnosis of AD. While brain lesions are a major feature of AD, retinal pathological changes also occur in patients. In this study, we investigated the temporal changes in β-site APP-cleaving enzyme 1 (BACE1) expression in the retina and brain to determine whether it could serve as a suitable biomarker for early monitoring of AD. APP/PS-1 transgenic mice, 3, 6 and 8 months of age, were used as an experimental group, and age-matched C57/BL6 wild-type mice served as the control group. In the Morris water maze test, there were no significant differences in escape latency or in the number of crossings in the target area among mice of different ages. Compared with wild-type mice, no changes in learning or memory abilities were detected in transgenic mice at 3 months of age. However, compared with wild-type mice, the escape latency was significantly increased in transgenic mice at 6 months, starting on day 3, and at 8 months, starting on day 2, during Morris water maze training. In addition, the number of crossings of the target area was significantly decreased in transgenic mice. The learning and memory abilities of transgenic mice were further worsened at 8 months of age. Immunohistochemical staining revealed no BACE1 plaques in wild-type mice at 3, 6 or 8 months or in transgenic mice at 3 months, but they were clearly found in the entorhinal cortex, hippocampus and prefrontal cortex of transgenic mice at 6 and 8 months. BACE1 expression was not detected in the retina of wild-type mice at 3 months, but weak BACE1 expression was detected in the ganglion cell layer, inner plexiform layer and outer plexiform layer at 6 and 8 months. In transgenic mice, BACE1 expression in the ganglion cell layer was increased at 3 months, and BACE1 expression in the ganglion cell

  2. The Climate Change Education Evidence Base: Lessons Learned from NOAA's Monitoring and Evaluation Framework Implementation

    Science.gov (United States)

    Baek, J.

    2012-12-01

    effort has provided some shared understanding and general guidance, there is still a lack of guidance to make decisions at any level of the community. A recent memorandum from the Office of Management and Budget provides more specific guidance around the generation and utilization of evidence. For example, the amount of funding awarded through grants should be weighted by the level of the evidence supporting a proposed project. As the field of climate change education establishes an evidence base, study designs should address a greater number of internal validity threats through comparison groups and reliable common measures. In addition, OMB invites agencies to develop systematic measurement of costs and costs per outcome. A growing evidence base, one that includes data that includes costs and even monetizes benefits, can inform decisions based on the strongest returns on investments within a portfolio. This paper will provide examples from NOAA's Monitoring and Evaluation Framework Implementation project that illustrate how NOAA is facing these challenges. This is intended to inform climate change educators, evaluators, and researchers in ways to integrate evaluation into the management of their programs while providing insight across the portfolio.

  3. A mathematical model of the influence of salivary urea on the pH of fasted dental plaque and on the changes occurring during a cariogenic challenge.

    Science.gov (United States)

    Dibdin, G H; Dawes, C

    1998-01-01

    Urea diffusing from saliva into dental plaque is converted to ammonia and carbon dioxide by bacterial ureases. The influence of normal salivary urea levels on the pH of fasted plaque and on the depth and duration of a Stephan curve is uncertain. A numerical model which simulates a cariogenic challenge (a 10% sucrose rinse alone or one followed by use of chewing-gum with or without sugar) was modified to include salivary urea levels from 0 to 30 mmol/l. It incorporated: site-dependent exchange between bulk saliva and plaque surfaces via a salivary film; sugar and urea diffusion into plaque; pH-dependent rates of acid formation and urea breakdown; diffusion and dissociation of end-products and other buffers (acetate, lactate, phosphate, ammonia and carbonate); diffusion of protons and other ions; equilibration with fixed and mobile buffers; and charge-coupling between ionic flows. The Km (2.12 mmol/l) and Vmax (0.11 micromol urea/min/mg dry weight) values for urease activity and the pH dependence of Vmax were taken from the literature. From the results, it is predicted that urea concentrations normally present in saliva (3-5 mmol/l) will increase the pH at the base of a 0.5-mm-thick fasted plaque by up to 1 pH unit, and raise the pH minimum after a sucrose rinse or sugar-containing chewing-gum by at least half a pH unit. The results suggest that plaque cariogenicity may be inversely related to salivary urea concentrations, not only when the latter are elevated because of disease, but even when they are in the normal range.

  4. On-Line Change Monitoring with Transformed Multi-Spectral Time Series, a Study Case in Tropical Forest

    Science.gov (United States)

    Lu, Meng; Hamunyela, Eliakim

    2016-10-01

    In recent years, the methods for detecting structural changes in time series have been adapted for forest disturbance monitoring using satellite data. The BFAST (Breaks For Additive Season and Trend) Monitor framework, which detects forest cover disturbances from satellite image time series based on empirical fluctuation tests, is particularly used for near real-time deforestation monitoring, and it has been shown to be robust in detecting forest disturbances. Typically, a vegetation index that is transformed from spectral bands into feature space (e.g. normalised difference vegetation index (NDVI)) is used as input for BFAST Monitor. However, using a vegetation index for deforestation monitoring is a major limitation because it is difficult to separate deforestation from multiple seasonality effects, noise, and other forest disturbance. In this study, we address such limitation by exploiting the multi-spectral band of satellite data. To demonstrate our approach, we carried out a case study in a deciduous tropical forest in Bolivia, South America. We reduce the dimensionality from spectral bands, space and time with projective methods particularly the Principal Component Analysis (PCA), resulting in a new index that is more suitable for change monitoring. Our results show significantly improved temporal delay in deforestation detection. With our approach, we achieved a median temporal lag of 6 observations, which was significantly shorter than the temporal lags from conventional approaches (14 to 21 observations).

  5. Effects of ETA, pH change, and increased hydrazine levels on deposit-covered Alloy 600 and brass corrosion at Indian Point 2

    Energy Technology Data Exchange (ETDEWEB)

    Barkatt, A.; Labuda, E.; Wilder, D.M. [Catholic Univ. of America, Washington, DC (United States); Smialowska, S.; Rebak, R.B. [Ohio State Univ., Columbus, OH (United States). Fontana Corrosion Center; Cherepakhov, G. [Consolidated Edison Co. of New York, Inc., NY (United States); Burns, R.J. [Consolidated Edison Co. of New York, Inc., Buchanan, NY (United States)

    1997-12-01

    Chemical dissolution tests and electrochemical tests were carried out on Alloy 600 specimens covered with synthetic deposit simulating the tube deposits in the steam generators at Indian Point 2. The tests showed that the introduction of ETA and a moderate increase in pH gave rise to lower corrosion rates, but enhancement of hydrazine levels caused them to rise. In the case of brass, both types of tests showed that raising the pH caused the corrosion rates to increase, but the introduction of ETA led to mild decrease in these rates.

  6. Exploring topographic methods for monitoring morphological changes in mountain channels of different size and slope

    Science.gov (United States)

    Theule, Joshua; Bertoldi, Gabriele; Comiti, Francesco; Macconi, Pierpaolo; Mazzorana, Bruno

    2015-04-01

    High resolution digital elevation models (DEM) can easily be obtained using either laser scanning technology or photogrammetry with structure from motion (SFM). The scale, resolution, and accuracy can vary according to how the data is acquired, such as by helicopter, drone, or extendable pole. In the Autonomous Province of Bozen-Bolzano (Northern Italy), we had the opportunity to compare several of these techniques at different scales in mountain streams ranging from low-gradient braided rivers to steep debris flow channels. The main objective is to develop protocols for efficient monitoring of morphologic changes in different parts of the river systems. For SFM methods, we used the software "Photoscan Professional" (Agisoft) to generate densified point clouds. Both artificial and natural targets were used to georeference them. In some cases, targets were not even necessary and point clouds could be aligned with older point clouds by using the iterative closest point algorithm in the freeware "CloudCompare". At the Mareit/Mareta River, a restored braided river, an airborne laser scan survey (2011) was compared to a SFM DEM derived from a helicopter photo survey (2014) carried out (by the Autonomous Province of Bolzano) at approximately 100 m above ground. Photogrammetry point clouds had an alignment error of 1.5 cm and had three times more data coverage than laser scanning. Indeed, the large spacing and clustering of 2011 ALS swaths led to areas of no data when a 10-cm grid is developed. In the Gadria basin, a debris flow monitoring catchment, we used a sediment retention basin to compare debris flow volumes resulting from i) a drone (by the "Mavtech" company) survey at 10 m above ground (with GoPro camera), ii) a 5-m pole-mounted camera (with Canon EOS 700D) and iii) a 3-m pole-mounted camera (with GoPro Hero Silver3+) to a iv) TLS survey. As the drone had limited load capacity (especially at high elevations) we used the lightweight GoPro Hero 3+, but due to the

  7. Monitoring mountain lakes in a changing Alpine cryosphere: the Lago Nero project (Ticino, Switzerland)

    Science.gov (United States)

    Scapozza, Cristian; Bruder, Andreas; Domenici, Mattia; Lepori, Fabio; Pera, Sebastian; Pozzoni, Maurizio; Rioggi, Stefano; Colombo, Luca

    2017-04-01

    Mountain lakes and their catchments of the Alpine cryosphere are facing global pressures including climate warming and deposition of atmospheric pollutants. Due to their remoteness, often low buffer capacities and sensitive biotic communities, alpine lake catchments are particularly well suited as sentinels of environmental change. Lago Nero is the object of an intensive survey, aimed at developing predictive models of catchment-wide ecosystem responses to environmental change (Bruder et al. 2016). Lago Nero is located at the head of Val Bavona (Canton Ticino, southern Switzerland), in a southwest-facing catchment, with altitude ranging from 2385 to 2842 m asl. The substrate is dominated by gneissic bedrock with patches of grassy vegetation and shallow soils. The catchment is snow-covered approximately from November to May. For a similar period, the lake is ice-covered. Lago Nero is an oligotrophic, soft-water lake with a surface of approximatively 13 ha and a maximal depth of 73 m. According to the regional model of potential permafrost distribution in the southern Swiss Alps (Scapozza & Mari 2010), the presence of discontinuous permafrost is probable in almost the entire surface of the catchment covered by loose debris. A direct evidence of permafrost occurrence is the presence of a small active/inactive rock glacier in the south-eastern part of the catchment (front altitude: 2560 m asl). Monitoring of the site began in summer 2014, with an initial phase aimed at developing and testing methodologies and at evaluating the suitability of the catchment and the feasibility of the monitoring program. The intensive survey at Lago Nero measures a wide array of ecosystem responses, including runoff quantity and chemistry, catchment soil temperature (also on the rock glacier) and composition of terrestrial vegetation. Sampling frequency depends on the parameter measured, varying from nearly continuous (e.g. runoff and temperature) to five-year intervals (e.g. soil and

  8. Changes in the viral distribution pattern after the appearance of the novel influenza A H1N1 (pH1N1 virus in influenza-like illness patients in Peru.

    Directory of Open Access Journals (Sweden)

    Victor Alberto Laguna-Torres

    Full Text Available BACKGROUND: We describe the temporal variation in viral agents detected in influenza like illness (ILI patients before and after the appearance of the ongoing pandemic influenza A (H1N1 (pH1N1 in Peru between 4-January and 13-July 2009. METHODS: At the health centers, one oropharyngeal swab was obtained for viral isolation. From epidemiological week (EW 1 to 18, at the US Naval Medical Research Center Detachment (NMRCD in Lima, the specimens were inoculated into four cell lines for virus isolation. In addition, from EW 19 to 28, the specimens were also analyzed by real time-polymerase-chain-reaction (rRT-PCR. RESULTS: We enrolled 2,872 patients: 1,422 cases before the appearance of the pH1N1 virus, and 1,450 during the pandemic. Non-pH1N1 influenza A virus was the predominant viral strain circulating in Peru through (EW 18, representing 57.8% of the confirmed cases; however, this predominance shifted to pH1N1 (51.5% from EW 19-28. During this study period, most of pH1N1 cases were diagnosed in the capital city (Lima followed by other cities including Cusco and Trujillo. In contrast, novel influenza cases were essentially absent in the tropical rain forest (jungle cities during our study period. The city of Iquitos (Jungle had the highest number of influenza B cases and only one pH1N1 case. CONCLUSIONS: The viral distribution in Peru changed upon the introduction of the pH1N1 virus compared to previous months. Although influenza A viruses continue to be the predominant viral pathogen, the pH1N1 virus predominated over the other influenza A viruses.

  9. Exploring Digital Surface Models from Nine Different Sensors for Forest Monitoring and Change Detection

    Directory of Open Access Journals (Sweden)

    Jiaojiao Tian

    2017-03-01

    Full Text Available Digital surface models (DSMs derived from spaceborne and airborne sensors enable the monitoring of the vertical structures for forests in large areas. Nevertheless, due to the lack of an objective performance assessment for this task, it is difficult to select the most appropriate data source for DSM generation. In order to fill this gap, this paper performs change detection analysis including forest decrease and tree growth. The accuracy of the DSMs is evaluated by comparison with measured tree heights from inventory plots (field data. In addition, the DSMs are compared with LiDAR data to perform a pixel-wise quality assessment. DSMs from four different satellite stereo sensors (ALOS/PRISM, Cartosat-1, RapidEye and WorldView-2, one satellite InSAR sensor (TanDEM-X, two aerial stereo camera systems (HRSC and UltraCam and two airborne laser scanning datasets with different point densities are adopted for the comparison. The case study is a complex central European temperate forest close to Traunstein in Bavaria, Germany. As a major experimental result, the quality of the DSM is found to be robust to variations in image resolution, especially when the forest density is high. The forest decrease results confirm that besides aerial photogrammetry data, very high resolution satellite data, such as WorldView-2, can deliver results with comparable quality as the ones derived from LiDAR, followed by TanDEM-X and Cartosat DSMs. The quality of the DSMs derived from ALOS and Rapid-Eye data is lower, but the main changes are still correctly highlighted. Moreover, the vertical tree growth and their relationship with tree height are analyzed. The major tree height in the study site is between 15 and 30 m and the periodic annual increments (PAIs are in the range of 0.30–0.50 m.

  10. Long-Term Monitoring of Glacier Change at GÖSSNITZKEES (austria) Using Terrestrial Photogrammetry

    Science.gov (United States)

    Kaufmann, V.; Seier, G.

    2016-06-01

    Gössnitzkees is a small heavily debris-covered cirque glacier (49.8 ha) located in the Schober Mountains, Hohe Tauern Range, Austrian Alps. Glacier nourishment is mainly due to avalanches descending from its surrounding headwalls. Gössnitzkees is the largest glacier in the Schober Mountains and is highly representative of the other 25 glaciers of this mountain group. All glaciers of this mountain group have receded continuously since 1850. Ongoing atmospheric warming sustains excessive glacier melt. In 1988 a long-term monitoring program was started at Gössnitzkees using terrestrial photogrammetry in order to document and quantify glacier change. The surveys have been repeated from time to time using different types of cameras. Recent surveys date from 2009, 2012, and 2015. The aim of this paper is twofold: firstly, to investigate whether or not the rather complex photogrammetric evaluation process using a conventional photogrammetric workstation (mostly with a limited degree of automation for terrestrial applications) can be replaced by modern fully automated Structure-from-Motion (SfM) based approaches, and secondly, to document and quantify the glacier change at Gössnitzkees based on available information augmented by results obtained from the most recent surveys mentioned. Over the last 27 years (1988-2015) the terminus of Gössnitzkees has receded by 179 m and the glacier ice has melted at a mean annual rate of about 1.5 m/year. The Schober Mountains are in the process of deglaciation and the glaciers will likely disappear within the next two decades. Based on our practical investigations we found out that SfM-based software is in general capable of handling terrestrial photographs in a fully automatic mode supporting challenging glacier studies.

  11. Long-term ERT monitoring of biogeochemical changes of an aged hydrocarbon contamination

    Science.gov (United States)

    Caterina, David; Flores Orozco, Adrian; Nguyen, Frédéric

    2017-06-01

    Adequate management of contaminated sites requires information with improved spatio-temporal resolution, in particular to assess bio-geochemical processes, such as the transformation and degradation of contaminants, precipitation of minerals or changes in groundwater geochemistry occurring during and after remediation procedures. Electrical Resistivity Tomography (ERT), a geophysical method sensitive to pore-fluid and pore-geometry properties, permits to gain quasi-continuous information about subsurface properties in real-time and has been consequently widely used for the characterization of hydrocarbon-impacted sediments. However, its application for the long-term monitoring of processes accompanying natural or engineered bioremediation is still difficult due to the poor understanding of the role that biogeochemical processes play in the electrical signatures. For in-situ studies, the task is further complicated by the variable signal-to-noise ratio and the variations of environmental parameters leading to resolution changes in the electrical images. In this work, we present ERT imaging results for data collected over a period of two years on a site affected by a diesel fuel contamination and undergoing bioremediation. We report low electrical resistivity anomalies in areas associated to the highest contaminant concentrations likely due transformations of the contaminant due to microbial activity and accompanying release of metabolic products. We also report large seasonal variations of the bulk electrical resistivity in the contaminated areas in correlation with temperature and groundwater level fluctuations. However, the amplitude of bulk electrical resistivity variations largely exceeds the amplitude expected given existing petrophysical models. Our results suggest that the variations in electrical properties are mainly controlled by microbial activity which in turn depends on soil temperature and hydrogeological conditions. Therefore, ERT can be suggested as

  12. Monitoring longitudinal changes in irradiated head and neck cancer xenografts using diffuse reflectance spectroscopy

    Science.gov (United States)

    Vishwanath, Karthik; Jiang, Shudong; Gunn, Jason R.; Marra, Kayla; Andreozzi, Jacqueline M.; Pogue, Brian W.

    2016-02-01

    Radiation therapy is often used as the preferred clinical treatment for control of localized head and neck cancer. However, during the course of treatment (6-8 weeks), feedback about functional and/or physiological changes within impacted tissue are not obtained, given the onerous financial and/or logistical burdens of scheduling MRI, PET or CT scans. Diffuse optical sensing is well suited to address this problem since the instrumentation can be made low-cost and portable while st