331 research outputs found
Maturity, ovarian cycle, fecundity, and age-specific parturition of black rockfish (Sebastes melanops)
From 1995 to 1998, we collected female black rockfish (Sebastes melanops) off Oregon in order to describe their basic reproductive life history and determine age-specific fecundity and temporal patterns in parturition. Female black rockfish had a 50% probability of being mature at 394 mm fork length and 7.5 years-of-age. The proportion of mature fish age 10 or older significantly decreased each year of this study, from 0.511 in 1996 to 0.145 in 1998. Parturition occurred between mid-January and mid-March, and peaked in February. We observed a trend of older females extruding larvae earlier in the spawning season and of younger fish primarily responsible for larval production during the later part of the season. There were differences in absolute fecundity at age between female black rockfish with prefertilization oocytes and female black rockfish with fertilized eggs; fertilized-egg fecundity estimates were considered superior. The likelihood of yolked oocytes reaching the developing embryo stage increased with maternal age. Absolute fecundity estimates (based on fertilized eggs) ranged from 299,302 embryos for a 6-year-old female to 948,152 embryos for a 16-year-old female. Relative fecundity (based on fertilized eggs) increased with age from 374 eggs/g for fish age 6 to 549 eggs/g for fish age 16
Nitro-Triarylmethyl Radical as Dual Oxygen and Superoxide Probe
Superoxide radical is involved in numerous physiological and pathophysiological processes. Tetrathiatriarylmethyl (TAM) radicals are knows to react with superoxide allowing measurement of superoxide production in biological media. We report the synthesis of a Nitro conjugated TAM radical showing a rate constant of 7 Γ 105 Mβ1sβ1 which is two order of magnitude higher than other TAMs allowing high sensitivity measurement of superoxid
Concurrent Longitudinal EPR Monitoring of Tissue Oxygenation, Acidosis, and Reducing Capacity in Mouse Xenograft Tumor Models
Tissue oxygenation, extracellular acidity and tissue reducing capacity are among crucial parameters of tumor microenvironment (TME) of significant importance for tumor pathophysiology. In this paper we demonstrate the complementary application of particulate lithium octa-n-butoxy-naphthalocyanine (LiNc-BuO) and soluble nitroxide (NR) paramagnetic probes for monitoring of these TME parameters using electron paramagnetic resonance (EPR) technique. Two different types of therapeutic interventions were studied: hypothermia and systemic administration of metabolically active drug. In summary, the results demonstrate utility of EPR technique for noninvasive concurrent longitudinal monitoring of physiologically relevant chemical parameters of TME in a mouse xenograft tumor models including that under therapeutic intervention
ΠΠ°ΡΡΡΠ΅Π½ΠΈΠ΅ ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΠΈΠΈ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΠΉ Hoilungia hongkongensis (Placozoa) Π² ΠΏΡΠΈΡΡΡΡΡΠ²ΠΈΠΈ ΠΈΠΎΠ½ΠΎΠ² Zn2+
Hoilungia hongkongensis ΠΏΡΠΈΠ½Π°Π΄Π»Π΅ΠΆΠΈΡ ΠΊ ΡΠΈΠΏΡ ΠΏΠ»Π°ΡΡΠΈΠ½ΡΠ°ΡΡΠ΅ (Placozoa) β ΠΏΡΠΎΡΡΠ΅ΠΉΡΠΈΠΌ ΠΌΠ½ΠΎΠ³ΠΎΠΊΠ»Π΅ΡΠΎΡΠ½ΡΠΌ ΠΎΡΠ³Π°Π½ΠΈΠ·ΠΌΠ°ΠΌ Ρ Π΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΠΌ ΠΏΠ»Π°Π½ΠΎΠΌ ΡΡΡΠΎΠ΅Π½ΠΈΡ ΡΠ΅Π»Π°. Π ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠ°Π½ΠΈΠΈ ΡΠ΅Π»ΠΎΡΡΠ½ΠΎΡΡΠΈ ΡΡΠΈΡ
ΠΆΠΈΠ²ΠΎΡΠ½ΡΡ
Π²Π°ΠΆΠ½ΡΡ ΡΠΎΠ»Ρ ΠΈΠ³ΡΠ°ΡΡ ΠΈΠΎΠ½Ρ ΠΊΠ°Π»ΡΡΠΈΡ. Π Π½Π°ΡΡΠΎΡΡΠ΅ΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΎ ΠΈΠ·ΡΡΠ΅Π½ΠΎ Π²Π»ΠΈΡΠ½ΠΈΠ΅ ΠΈΠΎΠ½ΠΎΠ² ΡΠΈΠ½ΠΊΠ° Π½Π° Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ ΠΊΠ»Π΅ΡΠΎΠΊ H. hongkongensis. ΠΡΠΈ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠΈ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΈΠΈ ΠΈΠΎΠ½ΠΎΠ² Zn2+ Π½Π° 20β25 ΠΌΠΊΠ Π½Π°ΡΡΡΠ°Π΅ΡΡΡ ΡΠΎΠ³Π»Π°ΡΠΎΠ²Π°Π½Π½ΠΎΡΡΡ Π°ΠΌΡΠ±ΠΎΠΈΠ΄Π½ΠΎΠ³ΠΎ Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΡ, ΡΡΠΎ ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΡ Β«Π²Π΅ΡΠ²ΠΈΡΡΡΡ
Β» ΡΠΎΡΠΌ ΠΆΠΈΠ²ΠΎΡΠ½ΠΎΠ³ΠΎ. ΠΠΎΠΊΠΎΠΌΠΎΡΠΎΡΠ½ΡΠ΅ ΡΠ΅ΡΠ½ΠΈΡΡΠ°ΡΡΠ΅ ΠΊΠ»Π΅ΡΠΊΠΈ Π΄Π²ΠΈΠ³Π°ΡΡΡΡ Ρ
Π°ΠΎΡΠΈΡΠ½ΠΎ ΠΈ Π½Π΅Π·Π°Π²ΠΈΡΠΈΠΌΠΎ Π΄ΡΡΠ³ ΠΎΡ Π΄ΡΡΠ³Π°. ΠΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΡ ΠΏΠΎΠΊΠ°Π·Π°Π»ΠΈ, ΡΡΠΎ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ½ΠΎΠ΅ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ ΠΊΠ»Π΅ΡΠΎΠΊ H. hongkongensis Π²Π°ΠΆΠ½ΠΎ Π΄Π»Ρ ΡΠΊΠΎΠΎΡΠ΄ΠΈΠ½ΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
Π΄Π²ΠΈΠΆΠ΅Π½ΠΈΠΉ ΠΎΡΠ³Π°Π½ΠΈΠ·ΠΌΠ°, Π² ΡΠΎ Π²ΡΠ΅ΠΌΡ ΠΊΠ°ΠΊ ΠΈΠΎΠ½Ρ ΡΠΈΠ½ΠΊΠ° ΠΌΠΎΠ³ΡΡ ΠΊΠΎΠ½ΠΊΡΡΠΈΡΠΎΠ²Π°ΡΡ Ρ ΠΈΠΎΠ½Π°ΠΌΠΈ ΠΊΠ°Π»ΡΡΠΈΡ, Π½Π°ΡΡΡΠ°Ρ ΡΠ΅Π³ΡΠ»ΡΡΠΈΡ ΠΈ ΡΠ°Π·ΡΡΡΠ°Ρ ΡΠ²ΡΠ·Ρ ΠΌΠ΅ΠΆΠ΄Ρ ΠΊΠ»Π΅ΡΠΊΠ°ΠΌΠΈ
Tuning the size and composition of manganese oxide nanoparticles through varying temperature ramp and aging time
Manganese oxide (MnO) nanoparticles (NPs) can serve as robust pH-sensitive contrast agents for magnetic resonance imaging (MRI) due to Mn2+ release at low pH, which generates a ~30 fold change in T1 relaxivity. Strategies to control NP size, composition, and Mn2+ dissolution rates are essential to improve diagnostic performance of pH-responsive MnO NPs. We are the first to demonstrate that MnO NP size and composition can be tuned by the temperature ramping rate and aging time used during thermal decomposition of manganese(II) acetylacetonate. Two different temperature ramping rates (10Β°C/min and 20Β°C/min) were applied to reach 300Β°C and NPs were aged at that temperature for 5, 15, or 30 min. A faster ramping rate and shorter aging time produced the smallest NPs of ~23 nm. Shorter aging times created a mixture of MnO and Mn3O4 NPs, whereas longer aging times formed MnO. Our results indicate that a 20Β°C/min ramp rate with an aging time of 30 min was the ideal temperature condition to form the smallest pure MnO NPs of ~32 nm. However, Mn2+ dissolution rates at low pH were unaffected by synthesis conditions. Although Mn2+ production was high at pH 5 mimicking endosomes inside cells, minimal Mn2+ was released at pH 6.5 and 7.4, which mimic the tumor extracellular space and blood, respectively. To further elucidate the effects of NP composition and size on Mn2+ release and MRI contrast, the ideal MnO NP formulation (~32 nm) was compared with smaller MnO and Mn3O4 NPs. Small MnO NPs produced the highest amount of Mn2+ at acidic pH with maximum T1 MRI signal; Mn3O4 NPs generated the lowest MRI signal. MnO NPs encapsulated within poly(lactide-co-glycolide) (PLGA) retained significantly higher Mn2+ release and MRI signal compared to PLGA Mn3O4 NPs. Therefore, MnO instead of Mn3O4 should be targeted intracellularly to maximize MRI contrast
Development of Multifunctional Overhauser-enhanced Magnetic Rresonance Imaging for Concurrent in Vivo Mapping of Tumor Interstitial Oxygenation, Acidosis and Inorganic Phosphate Concentration
Tumor oxygenation (pO2), acidosis (pH) and interstitial inorganic phosphate concentration (Pi) are important parameters of the malignant behavior of cancer. A noninvasive procedure that enables visualization of these parameters may provide unique information about mechanisms of tumor pathophysiology and provide clues to new treatment targets. In this research, we present a multiparametric imaging method allowing for concurrent mapping of pH, spin probe concentration, pO2, and Pi using a single contrast agent and Overhauser-enhanced magnetic resonance imaging technique. The developed approach was applied to concurrent multifunctional imaging in phantom samples and in vivo in a mouse model of breast cancer. Tumor tissues showed higher heterogeneity of the distributions of the parameters compared with normal mammary gland and demonstrated the areas of significant acidosis, hypoxia, and elevated Pi content
Evaluation of the efficiency of biocomposting of bottom silt deposits using different conditions of aerobic fermentation
The efficiency of biocomposting of bottom silt deposits was evaluated in laboratory conditions. The biocomposting process is reproduced taking into account the main technological parameters and using lowland peat, microbial concentrate and vermiculture as basic components. The composition of the microbial concentrate includes strains of the genera Bacillus spp., Clostridium spp., Pseudomonas spp., causing biosolubilization of a complex organomineral substrate - bottom sediments. The productive line Eisenia foetida Savigny (Lumbricidae) was used as a vermiculture. The evaluation of the efficiency of biocomposting was carried out according to agrochemical characteristics. The greatest effect on the preservation of biogens was obtained during the fermentation of bottom sediments with the participation of microbial concentrate. An increase in the content of N to 1.10%, P β to 0.54%, K β to 0.42% was achieved. The use of vermiculture caused an increase in organic matter β up to 42.1% and humus β up to 14.6%. The results of the experiment allow us to consider biocompost and vermicompost obtained using bottom sediments as a source of elements necessary for plant growth and development
Interstitial Inorganic Phosphate as a Tumor Microenvironment Marker for Tumor Progression
Noninvasive in vivo assessment of chemical tumor microenvironment (TME) parameters such as oxygen (pO2), extracellular acidosis (pHe), and concentration of interstitial inorganic phosphate (Pi) may provide unique insights into biological processes in solid tumors. In this work, we employ a recently developed multifunctional trityl paramagnetic probe and electron paramagnetic resonance (EPR) technique for in vivo concurrent assessment of these TME parameters in various mouse models of cancer. While the data support the existence of hypoxic and acidic regions in TME, the most dramatic differences, about 2-fold higher concentrations in tumors vs. normal tissues, were observed for interstitial Pi - the only parameter that also allowed for discrimination between non-metastatic and highly metastatic tumors. Correlation analysis between [Pi], pO2, pHe and tumor volumes reveal an association of high [Pi] with changes in tumor metabolism and supports different mechanisms of protons and Pi accumulation in TME. Our data identifies interstitial inorganic phosphate as a new TME marker for tumor progression. Pi association with tumor metabolism, buffer-mediated proton transport, and a requirement of high phosphorus content for the rapid growth in the βgrowth rate hypothesisβ may underline its potential role in tumorigenesis and tumor progression
Interstitial Inorganic Phosphate as a Tumor Microenvironment Marker for Tumor Progression
Noninvasive in vivo assessment of chemical tumor microenvironment (TME) parameters such as oxygen (pO2), extracellular acidosis (pHe), and concentration of interstitial inorganic phosphate (Pi) may provide unique insights into biological processes in solid tumors. In this work, we employ a recently developed multifunctional trityl paramagnetic probe and electron paramagnetic resonance (EPR) technique for in vivoconcurrent assessment of these TME parameters in various mouse models of cancer. While the data support the existence of hypoxic and acidic regions in TME, the most dramatic differences, about 2-fold higher concentrations in tumors vs. normal tissues, were observed for interstitial Pi - the only parameter that also allowed for discrimination between non-metastatic and highly metastatic tumors. Correlation analysis between [Pi], pO2, pHe and tumor volumes reveal an association of high [Pi] with changes in tumor metabolism and supports different mechanisms of protons and Pi accumulation in TME. Our data identifies interstitial inorganic phosphate as a new TME marker for tumor progression. Pi association with tumor metabolism, buffer-mediated proton transport, and a requirement of high phosphorus content for the rapid growth in the βgrowth rate hypothesisβ may underline its potential role in tumorigenesis and tumor progression
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Using fNIRS to Identify Transparency- and Reliability-Sensitive Markers of Trust Across Multiple Timescales in Collaborative Human-Human-Agent Triads
Intelligent agents are rapidly evolving from assistants into teammates as they perform increasingly complex tasks. Successful human-agent teams leverage the computational power and sensory capabilities of automated agents while keeping the human operator's expectation consistent with the agent's ability. This helps prevent over-reliance on and under-utilization of the agent to optimize its effectiveness. Research at the intersection of human-computer interaction, social psychology, and neuroergonomics has identified trust as a governing factor of human-agent interactions that can be modulated to maintain an appropriate expectation. To achieve this calibration, trust can be monitored continuously and unobtrusively using neurophysiological sensors. While prior studies have demonstrated the potential of functional near-infrared spectroscopy (fNIRS), a lightweight neuroimaging technology, in the prediction of social, cognitive, and affective states, few have successfully used it to measure complex social constructs like trust in artificial agents. Even fewer studies have examined the dynamics of hybrid teams of more than 1 human or 1 agent. We address this gap by developing a highly collaborative task that requires knowledge sharing within teams of 2 humans and 1 agent. Using brain data obtained with fNIRS sensors, we aim to identify brain regions sensitive to changes in agent behavior on a long- and short-term scale. We manipulated agent reliability and transparency while measuring trust, mental demand, team processes, and affect. Transparency and reliability levels are found to significantly affect trust in the agent, while transparency explanations do not impact mental demand. Reducing agent communication is shown to disrupt interpersonal trust and team cohesion, suggesting similar dynamics as human-human teams. Contrasts of General Linear Model analyses identify dorsal medial prefrontal cortex activation specific to assessing the agent's transparency explanations and characterize increases in mental demand as signaled by dorsal lateral prefrontal cortex and frontopolar activation. Short scale event-level data is analyzed to show that predicting whether an individual will trust the agent, with data from 15 s before their decision, is feasible with fNIRS data. Discussing our results, we identify targets and directions for future neuroergonomics research as a step toward building an intelligent trust-modulation system to optimize human-agent collaborations in real time.
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