Thermometer Probe Research Articles

Anti-pyretic, Anti-inflammatory and Analgesic Activities of Aqueous Stem Extract of Cynanchum Viminale (L.) in Albino Mice

Cynanchum viminale has been used to manage several diseases including pain, inflammation and fever. However, its efficacy has not been scientifically validated. The aim of this study therefore is to investigate the analgesic, antipyretic and anti-inflammatory activities of its aqueous extracts. The plant extract was collected from Loita division, Narok county in Kenya. A total of 96 albino mice with an average weight of 20 g were used for this study. Analgesic activity was determined by use of formalin−induced writhing test. A writhe was recorded by a stopwatch following the stretching of the abdomen and/or stretching of at least one hind limb. Anti-inflammatory activity was established by a formalin induced inflammation test. Hourly changes in paw sizes and reduction of edema around the paw was determined using a venier calipers. Antipyretic activity was carried out using Brewer’s yeast induced pyrexia. Temperature of each mouse was determined rectally by thermal probe thermometer. The aqueous leaf extracts of C. viminale reduced pain, inflammation and fever mostly at dose 150 mg/kg body weight. Based on these findings it was concluded that the present study has demonstrated the analgesic, anti-inflammatory and antipyretic potential of aqueous leaf extracts of C. viminale in albino mice and will serve as good bio-resource for generating readily available herbal formulations that are more effective in the treatment of pain, inflammation and fever.

Antipyretic, Antiinflammatory and Antinociceptive Activities of Aqueous Bark Extract of Acacia Nilotica (L.) Delile in Albino Mice

Acacia nilotica has been used to manage several diseases including pain, inflammation and fever. However, its efficacy has not been scientifically validated. The aim of this study therefore is to investigate the antinociceptive, antipyretic and anti-inflammatory activities of its aqueous extracts. The plant extract was collected from Loita division, Narok county in Kenya. A total of 96 albino mice with an average weight of 20 g was used for this study. Antinociceptive activity was determined by use of formalin−induced writhing test. A writhe was recorded by a stopwatch following the stretching of the abdomen and/or stretching of at least one hind limb. Anti-inflammatory activity was established by a formalin induced inflammation test. Hourly changes in paw sizes and reduction of edema around the paw was determined using a venier calipers. Antipyretic activity was carried out using Brewer’s yeast induced pyrexia. Temperature of each mouse was determined rectally by thermal probe thermometer. The aqueous leaf extracts of A. nilotica reduced pain, inflammation and fever mostly at dose 150 mg/kg body weight. Based on these findings it was concluded that the present study has demonstrated the antinociceptive, anti-inflammatory and antipyretic potential of aqueous leaf extracts of A. nilotica in albino mice and will serve as good bio-resource for generating readily available herbal formulations that are more effective in the treatment of pain, inflammation and fever conditions which are cheaper than the conventional synthetic drugs and have no side effects.

Anti-pyretic, Anti-inflammatory and Analgesic Activities of Aqueous Leaf Extract of Urtica Dioica (L.) in Albino Mice

Urtica dioica has been used to manage several diseases including pain, inflammation and fever. However, its efficacy has not been scientifically validated. The aim of this study therefore is to investigate the analgesic, antipyretic and anti-inflammatory activities of its aqueous extracts. The plant extract was collected from Loita division, Narok County in Kenya. A total of 96 albino mice with an average weight of 20 g were used for this study. Analgesic activity was determined by use of formalin−induced writhing test. A writhe was recorded by a stopwatch following the stretching of the abdomen and/or stretching of at least one hind limb. Anti-inflammatory activity was established by a formalin induced inflammation test. Hourly changes in paw sizes and reduction of edema around the paw was determined using a venier calipers. Antipyretic activity was carried out using Brewer’s yeast induced pyrexia. Temperature of each mouse was determined rectally by thermal probe thermometer. The aqueous leaf extracts of Urtica dioica reduced pain, inflammation and fever mostly at dose 150 mg/kg body weight. Based on these findings it was concluded that the present study has demonstrated the analgesic, anti-inflammatory and antipyretic potential of aqueous leaf extracts of Urtica dioica in albino mice and will serve as good bio-resource for generating readily available herbal formulations that are more effective in the treatment of pain, inflammation and fever conditions which are cheaper than the conventional synthetic drugs and have no side effects.

Antipyretic, Anti-inflammatory and Analgesic Activities of Aqueous Leaf Extract of Aloe volkensii in Albino Mice

Aloe volkensii has been used to manage several diseases including pain, inflammation and fever. However, its efficacy has not been scientifically validated. The aim of this study therefore is to investigate the analgesic, antipyretic and anti-inflammatory activities of its aqueous extracts. The plant was collected from Loita division, Narok County in Kenya. A total of 96 albino mice with an average weight of 20 g were used for this study. Analgesic activity was determined by use of 0.05 ml of 2.5% formalin−induced writhing test. A writhe was recorded by a stopwatch following the stretching of the abdomen and/or stretching of at least one hind limb. Anti-inflammatory activity was established by a formalin induced inflammation test. Hourly changes in paw sizes and reduction of edema around the paw was determined using a vernier calipers. Antipyretic activity was carried out using 0.03 g of 10 ml/kg of 15% w/v Brewer’s yeast-induced pyrexia. Temperature of each mouse was determined rectally by thermal probe thermometer. The aqueous leaf extracts of Aloe volkensii reduced pain, inflammation and fever mostly at dose 150 mg/kg body weight compared to dose of 50 mg/kg and 100 mg/kg body weight. The results support the traditional use of A. volkensii in the treatment of various diseases associated with pain, fever and inflammation.

Monitoring and Thermal Analysis of Co-Composting Process in a Forest Nursery Modern (Tunisia)

The objective of this work was to study thermogenesis during the process of Co-composting to assess the possibilities of thermal destruction of the germination capacity of weeds seeds. A regular monitoring of temperature has been achieved, using a probe thermometer, at nine locations of heap crafted. The outlines of temperature profiles allowed the identification of the four phases of the process, from a temperature monitoring, which is taken twice a day.The mid-monthly monitoring of temperature showed no significant differences for the first three dates of monitoring, whatever the depth and whatever time study. The bi-monthly monitoring showed insignificant differences for the first three dates, whatever the depth of the heap and whatever the studied time. The last three dates showed insignificant differences for the time of recording, whereas for the depth, the results obtained were significant.

Effects of Temperature and X-rays on Plastic Scintillating Fiber and Infrared Optical Fiber

In this study, we have studied the effects of temperature and X-ray energy variations on the light output signals from two different fiber-optic sensors, a fiber-optic dosimeter (FOD) based on a BCF-12 as a plastic scintillating fiber (PSF) and a fiber-optic thermometer (FOT) using a silver halide optical fiber as an infrared optical fiber (IR fiber). During X-ray beam irradiation, the scintillating light and IR signals were measured simultaneously using a dosimeter probe of the FOD and a thermometer probe of the FOT. The probes were placed in a beaker with water on the center of a hotplate, under variation of the tube potential of a digital radiography system or the temperature of the water in the beaker. From the experimental results, in the case of the PSF, the scintillator light output at the given tube potential decreased as the temperature increased in the temperature range from 25 to 60 °C. We demonstrated that commonly used BCF-12 has a significant temperature dependence of −0.263 ± 0.028%/°C in the clinical temperature range. Next, in the case of the IR fiber, the intensity of the IR signal was almost uniform at each temperature regardless of the tube potential range from 50 to 150 kVp. Therefore, we also demonstrated that the X-ray beam with an energy range used in diagnostic radiology does not affect the IR signals transmitted via a silver halide optical fiber.

The Effects of Nmda Antagonists On Morphine Induced Hyperthermia in Rats

Objectives NMDA receptor antagonists, are known for their anesthetic, analgesic and anti-shivering properties. This study is aimed at evaluating the effects of ketamine and magnesium sulphate on body temperature in rats, and to determine the type of interaction between them. Methods The body temperature was measured by insertion of a thermometer probe 5 cm into the colon of unrestrained male Wistar rats (200-250 g). Results Magnesium sulphate (5 and 60 mg/kg, sc) showed influence neither on baseline, nor on morphine-evoked hyperthermic response. Subanesthetic doses of ketamine (5-30 mg/kg, ip) given alone, produced significant dose-dependent reduction in both baseline colonic temperature and morphine-induced hyperthermia. Analysis of the log dose–response curves for the effects of ketamine and ketamine-magnesium sulphate combination on the baseline body temperature revealed synergistic interaction, and about 5.3 fold reduction in dosage of ketamine when the drugs were applied in fixed ratio (1:1) combinations. In addition, fixed low dose of magnesium sulphate (5 mg/kg, sc) enhanced the temperature lowering effect of ketamine (1.25-10 mg/kg, ip) on baseline body temperature and morphine-induced hyperthermia by factors of about 2.5 and 5.3, respectively. Conclusion This study is first to demonstrate the synergistic interaction between magnesium sulphate and ketamine in lowering morhine induced hyperthermia. It is possible that the synergy between ketamine and magnesium may have clinical relevance.

Joining time-resolved thermometry and magnetic-induced heating in a single nanoparticle unveils intriguing thermal properties.

Whereas efficient and sensitive nanoheaters and nanothermometers are demanding tools in modern bio- and nanomedicine, joining both features in a single nanoparticle still remains a real challenge, despite the recent progress achieved, most of it within the last year. Here we demonstrate a successful realization of this challenge. The heating is magnetically induced, the temperature readout is optical, and the ratiometric thermometric probes are dual-emissive Eu(3+)/Tb(3+) lanthanide complexes. The low thermometer heat capacitance (0.021·K(-1)) and heater/thermometer resistance (1 K·W(-1)), the high temperature sensitivity (5.8%·K(-1) at 296 K) and uncertainty (0.5 K), the physiological working temperature range (295-315 K), the readout reproducibility (>99.5%), and the fast time response (0.250 s) make the heater/thermometer nanoplatform proposed here unique. Cells were incubated with the nanoparticles, and fluorescence microscopy permits the mapping of the intracellular local temperature using the pixel-by-pixel ratio of the Eu(3+)/Tb(3+) intensities. Time-resolved thermometry under an ac magnetic field evidences the failure of using macroscopic thermal parameters to describe heat diffusion at the nanoscale.

Characteristics of ocular temperature elevations after exposure to quasi- and millimeter waves (18-40 GHz)

In order to investigate changes in ocular temperature in rabbit eyes exposed to different frequencies (18 to 40 GHz) of quasi-millimeter waves, and millimeter waves (MMW). Pigmented rabbits were anesthetized with both general and topical anesthesia, and thermometer probes (0.5 mm in diameter) were inserted into their cornea (stroma), lens (nucleus) and vitreous (center of vitreous). The eyes were exposed unilaterally to 200 mW/cm2 by horn antenna for 3 min at 18, 22 and 26.5 GHz using a K band exposure system or 26.5, 35 and 40 GHz using a Ka band exposure system. Changes in temperature of the cornea, lens and vitreous were measured with a fluoroptic thermometer. Since the ocular temperatures after exposure to 26.5 GHz generated by the K band and Ka band systems were similar, we assumed that experimental data from these 2 exposure systems were comparable. The highest ocular temperature was induced by 40 GHz MMW, followed by 35 GHz. The 26.5 and 22 GHz corneal temperatures were almost the same. The lowest temperature was recorded at 18 GHz. The elevation in ocular temperature in response to exposure to 200 mW/cm2 MMW is dependent on MMW frequency. MMW exposure induced heat is conveyed not only to the cornea but also the crystalline lens.

Comparison of Air Temperature Calibrations

European national metrology institutes use calibration systems of various types for calibrating thermometers in air. These were compared to each other for the first time in a project organized by the European Association of National Metrology Institutes (EURAMET). This EURAMET P1061 comparison project had two main objectives: (1) to study the equivalence of calibrations performed by different laboratories and (2) to investigate correlations between calibration methods and achievable uncertainties. The comparison was realized using a pair of 100 $$\Omega $$ platinum resistance thermometer probes connected to a digital thermometer bridge as the transfer standard. The probes had different dimensions and surface properties. The measurements covered the temperature range between $$-40\,^{\circ }\mathrm{{C}}$$ and $$+150\,^{\circ }\mathrm{{C}}$$ , but each laboratory chose a subrange most relevant to its scope and performed measurements at five nominal temperature points covering the subrange. To enable comparison between the laboratories, comparison reference functions were determined using weighted least-squares fitting. Various effects related to variations in heat transfer conditions were demonstrated but clear correlations to specific characteristics of calibration system were not identified. Calibrations in air and liquid agreed typically within $$\pm 0.05\,^{\circ }\mathrm{{C}}$$ at $$+10\,^{\circ }\mathrm{{C}}$$ and $$+80\,^{\circ }\mathrm{{C}}$$ . Expanded uncertainties determined by the participants ranged from $$0.02\,^{\circ }\mathrm{{C}}$$ to $$0.4\,^{\circ }\mathrm{{C}}$$ and they were shown to be realistic in most cases.

Specific Sorting and Post-Golgi Trafficking of Dendritic Potassium Channels in Living Neurons

Proper membrane localization of ion channels is essential for the function of neuronal cells. Particularly, the computational ability of dendrites depends on the localization of different ion channels in specific subcompartments. However, the molecular mechanisms that control ion channel localization in distinct dendritic subcompartments are largely unknown. Here, we developed a quantitative live cell imaging method to analyze protein sorting and post-Golgi vesicular trafficking. We focused on two dendritic voltage-gated potassium channels that exhibit distinct localizations: Kv2.1 in proximal dendrites and Kv4.2 in distal dendrites. Our results show that Kv2.1 and Kv4.2 channels are sorted into two distinct populations of vesicles at the Golgi apparatus. The targeting of Kv2.1 and Kv4.2 vesicles occurred by distinct mechanisms as evidenced by their requirement for specific peptide motifs, cytoskeletal elements, and motor proteins. By live cell and super-resolution imaging, we identified a novel trafficking machinery important for the localization of Kv2.1 channels. Particularly, we identified non-muscle myosin II as an important factor in Kv2.1 trafficking. These findings reveal that the sorting of ion channels at the Golgi apparatus and their subsequent trafficking by unique molecular mechanisms are crucial for their specific localizations within dendrites.

Synergistic interaction between ketamine and magnesium in lowering body temperature in rats

A large body of evidence supports the existence of an endogenous glutamate system that tonically modulates body temperature via N-methyl-d-aspartate (NMDA) receptors. Ketamine and magnesium, both NMDA receptor antagonists, are known for their anesthetic, analgesic and anti-shivering properties. This study is aimed at evaluating the effects of ketamine and magnesium sulfate on body temperature in rats, and to determine the type of interaction between them. The body temperature was measured by insertion of a thermometer probe 5cm into the colon of unrestrained male Wistar rats (200–250g). Magnesium sulfate (5 and 60mg/kg, sc) showed influence neither on baseline, nor on morphine-evoked hyperthermic response. Subanesthetic doses of ketamine (5–30mg/kg, ip) given alone, produced significant dose-dependent reduction in both baseline colonic temperature and morphine-induced hyperthermia. Analysis of the log dose–response curves for the effects of ketamine and ketamine–magnesium sulfate combination on the baseline body temperature revealed synergistic interaction, and about 5.3 fold reduction in dosage of ketamine when the drugs were applied in fixed ratio (1:1) combinations. In addition, fixed low dose of magnesium sulfate (5mg/kg, sc) enhanced the temperature lowering effect of ketamine (1.25–10mg/kg, ip) on baseline body temperature and morphine-induced hyperthermia by factors of about 2.5 and 5.3, respectively. This study is the first to demonstrate the synergistic interaction between magnesium sulfate and ketamine in a whole animal study and its statistical confirmation. It is possible that the synergy between ketamine and magnesium may have clinical relevance.

EPA-0510 - A comparison of the effect of morphine and fentanyl derivatives on the antinociception and body temperature in rats

In addition to producing antinociception, opioids exert profound effects on body temperature. This study aimed at comparing antinociceptive and hyperthermic responses between two groups of μ-opioid receptor agonists: fentanyl (4- anilinopiperidine-type) and morphine (phenanthrene-type) derivatives in rats. Analgesic activity was assessed by tail-immersion test in male Wistar rats (200–250 g). The distal 5 cm of the tail was immersed in a warm water bath (55 + 0.5°C) and the time for tail-withdrawal was measured as a response latency. The body temperature was measured by insertion of a thermometer probe 5 cm into the colon of unrestrained rats. Fentanyl (F), (±)cis-3-methyl fentanyl (CM), (±)cis-3-carbomethoxy fentanyl (C), (±)trans-3-carbomethoxy fentanyl (T) and (±)cis-3 butyl fentanyl (B) produced dose-dependent increase in antinociception and hyperthermia. The relative order of analgesic potency was: CM(11.27)>F(1)>C(0.35) 3 T(0.11) 3 B (0.056). Similar to this, the relative order of hyperthermic potency was: CM(8.43)>F(1)>C(0.46) 3 T(0.11) 3 B(0.076). Morphine (M), oxycodone (O), thebacon (T) and 6,14-Ethenomorphinan-7-methanol, 4,5-epoxy-6- fluoro-3-hydroxy-a, a,17-trimethyl-, (5a,7a) (E) also produced dose-dependent increase in antinociception and hyperthermia. Among morphine derivatives the relative order of analgesic potency was: E(56)>O(5) 3 T(2.6)>M(1), and similar to this, the relative order of hyperthermic potency was: E(37)>O(3) 3 T(2.3)>M(1). Morphine (phenanthrene-type) and fentanyl (4-anilinopiperidine-type) derivatives produced hyperthermia in rats at doses about 2 times lower, and 6 to 11 times higher, than their median antinociceptive doses, respectively. This study is first to identify difference between these two classes of opioid drugs in their potencies in producing hyperthermia.

Thermometer-free Detection and Control of Temperature for Microwave-assisted Flow Reactions

Abstract Thermometer-free sensing of temperature in a microwave (MW)-assisted flow reactor was realized from the variation of resonance frequency associated with the dielectric property of the target material. This method enabled detection and control of water flow temperature with 1.5 °C precision without use of a thermometer probe.

A comparison of the antinociceptive and temperature responses to morphine and fentanyl derivatives in rats

In addition to producing antinociception, opioids exert profound effects on body temperature. This study aimed at comparing antinociceptive and hyperthermic responses between two groups of μ-opioid receptor agonists: fentanyl (4-anilinopiperidine-type) and morphine (phenanthrene-type) derivatives in rats. Analgesic activity was assessed by tail immersion test and the body temperature by insertion of a thermometer probe into the colon. Fentanyl (F), (±)-cis-3-methyl fentanyl (CM), (±)-cis-3-carbomethoxy fentanyl (C), (±)trans-3-carbomethoxy fentanyl (T) and (±)-cis-3 butyl fentanyl (B) produced dose-dependent increase in antinociception and hyperthermia. The relative order of analgesic potency was: CM(11.27)>F(1)>C(0.35)≥T(0.11)≥B(0.056). Similar to this, the relative order of hyperthermic potency was: CM(8.43)>F(1)>C(0.46)≥T(0.11)≥B(0.076). Morphine (M), oxycodone (O), thebacon (T) and 6,14-ethenomorphinan-7-methanol, 4,5-epoxy-6-fluoro-3-hydroxy-α,α,17-trimethyl-, (5α,7α) (E) also produced dose-dependent increase in antinociception and hyperthermia. Among morphine derivatives the relative order of analgesic potency was: E(56)>O(5)≥T(2.6)>M(1), and similar to this, the relative order of hyperthermic potency was: E(37)>O(3)≥T(2.3)>M(1). Morphine (phenanthrene-type) and fentanyl (4-anilinopiperidine-type) derivatives produced hyperthermia in rats at doses about 2 times lower, and 6-11 times higher, than their median antinociceptive doses, respectively. This study is first to identify difference between these two classes of opioid drugs in their potencies in producing hyperthermia. Further studies are needed to clarify the significance of these findings.

Clinical evaluation of a new technique to monitor return electrode skin temperature during radiofrequency ablation

Return electrode burns occur occasionally in cardiac radiofrequency ablation and more frequently in tumor radiofrequency ablation. A return electrode incorporating a thermochromic liquid crystal (TLC) layer, which changes color with temperature, has been shown in sheep studies to accurately indicate underlying skin temperature. We aimed to validate the accuracy of TLC-coated return electrodes in indicating skin temperature in the clinical setting of cardiac radiofrequency ablation. The top layer of a standard return electrode was replaced with TLC. Fluoro-optic thermometer (FOT) probes were laid on the skin side of the return electrode, which was then placed on the left lateral mid-thigh of 18 patients (mean age = 61 ± 12 years, 12 men) undergoing cardiac radiofrequency ablation. Return electrode photographs were taken when FOT temperature exceeded 35 °C. TLC color changes, observed in 11 patients, were converted to temperature and compared with FOT temperature. TLC temperature correlated well with FOT temperature (Pearson's coefficient = 0.97 ± 0.03). Bland-Altman analysis showed good agreement (mean temperature difference = -0.04 ± 0.08 °C, upper limit of agreement = 0.11 ± 0.005 °C, lower limit of agreement = -0.19 ± 0.005 °C). The maximum FOT temperature recorded was 39.6 °C. There was no thermal injury at the return electrode site on any patients, when assessed immediately after and the day following the procedure. TLC-coated return electrodes accurately indicate underlying skin temperature in cardiac radiofrequency ablation and may help prevent burns. This technology might be essential in high energy radiofrequency ablation.

Frequency of Brugada type ECG pattern in male subjects with fever

Fever is considered as one of the implicated factors for Brugada type ECG pattern (BTEP). Numerous case reports highlighted the association of feverwith Brugada syndrome (BS) because certain subjectswith high fever displayed BTEP and experienced sudden cardiac death or ventricular arrhythmias [1–5]. However, there is still a lack of prospective data about the true frequency of BTEP among subjects with fever. ECG is usually not recorded in an otherwise healthy noncardiac patientwho comes inwith fever. If an ECGof a subjectwith fever is recorded, it is usually because of either an arrhythmic event or chest pain. Therefore, the aim of the present study was to determine the true frequency of BTEP in male subjects with fever by recording ECGs at standard and high right intercostal spaces (ICS). BetweenMay and December 2011, male subjects with fever (n=210) who presented to the emergency department were evaluated for study enrollment. Feverwasdefinedas a single body temperaturemeasurement of ≥38.3 °C (101.0 °F) or a body temperature of 38.0–38.2 °C (100.4– 100.9 °F) persistent for 1 h by tympanic thermometer probe. Subjects with any known cardiac and metabolic disorder as well as electrolyte abnormality, history of syncope and/or arrhythmia, bundle branch block and/or atrial fibrillation on ECG, family history of SCD and subjects who disclosedanykindof drugor substanceusewerenot included in the study. After exclusion 103 male subjects with fever were prospectively and consecutively included in the study. After the body temperature was measured, ECGs were recorded during febrile state at standard lead locations and also placing the right precordial (V1–3) leads at the 3rd and 2nd ICS. Subsequently, oral paracetamol was administered and cold compress was applied for alleviating fever. If the body temperature was b38.0 °C (100.4 °F), the subjects were considered to be afebrile. After a waiting period of 30 min during the afebrile state, ECGs were again recorded with the same order and technique. Twelve-lead surface ECGs were obtained from all subjects in a supine position at a paper speed of 25 mm/s and a calibration of 10 mm/mV. Electrocardiograms were obtained by the same investigator with the same ECG recorder (Nihon Kohden ECG-9020K, Japan). All ECG sampleswithout knowingwhich one was recorded during the febrile state were then blindly evaluated by two independent reviewers for the presence of BTEP according to the Second BrugadaConsensusConference criteria [1]. The studyprotocol conforms to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in a priori approval by the institution's human research committee. Written informed consent was obtained from all subjects. The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology. The age, body

Antipsychotic and sedative effects of the leaf extract of Crassocephalum bauchiense (Hutch.) Milne-Redh (Asteraceae) in rodents

Ethnopharmacological relevanceCrassocephalum bauchiense (Hutch.) Milne-Redh (Asteraceae) has been used as a medicine for the treatment of epilepsy, insomnia, dementia and psychotic disorders in Cameroonian traditional medicine. Aim of the studyThis study was designed to examine whether the aqueous extract and the alkaloid fraction prepared from the leaves of Crassocephalum bauchiense possess antipsychotic and sedative properties in rodents. Materials and methodsThe rectal temperature of mice was recorded with a probe thermometer at a constant depth. Novelty-induced rearing behavior is used to evaluate a central excitatory locomotor behavior in mice. The antipsychotic effects of the extracts were assessed using the apomorphine animal model of psychosis. The catalepsy test was tested based on the ability of the leaves extracts of Crassocephalum bauchiense to alter the duration of akinesia by placing the naive mice with both forelegs over a horizontal bar. The extracts of Crassocephalum bauchiense effects were evaluated on sodium pentobarbital-induced sleeping time. In addition, gamma-aminobutyric acid concentrations in the brain treated mice were also estimated. ResultsThe aqueous extract and the alkaloid fraction from Crassocephalum bauchiense caused dose-dependent inhibition of novelty-induced rearing behavior, decreased the apomorphine-induced stereotypy and fighting, and had significant fall of the body temperature. The aqueous extract prolonged the sodium pentobarbital sleeping time. This prolongation was not reversed by bicuculline, a light-sensitive competitive antagonist of GABAA receptors complex. However, the effect of the aqueous extract on sodium pentobarbital-induced sleeping time was blocked by N-methyl-β-carboline-3-carboxamide, a partial inverse agonist of the benzodiazepine site in the GABAA receptor complex and flumazenil, a specific antagonist of the benzodiazepine site in the GABAA receptor complex. In biochemical experiments, the concentration of the inhibitory amino acid, gamma-aminobutyric acid, was significantly increased in the brain of animals treated with the aqueous extract of Crassocephalum bauchiense and sodium valproate. ConclusionsThe results show that the antipsychotic and sedative properties of Crassocephalum bauchiense are possibly mediated via the blockade of dopamine D-2 receptors and GABAergic activation, respectively. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for these neuropharmacological actions and also to identify the active substances present in the extracts of Crassocephalum bauchiense.

Experimental characterisation of a plume above rectangular thermal sources. Effect of aspect ratio

An experimental study of the thermal plume emerging above a number of plane rectangular heat sources of finite dimensions was performed with the aim of verifying the corresponding point source or linear source models and the evolutions of the dynamic and thermal fields in relation to the aspect ratio. The heat sources were assembled from four rectangular units 1.5 m in length and 0.25 m in width. Four different configurations with aspect ratios between 1.5 and 6 were tested. Surface temperatures were chosen to maintain approximately the same convected power from the sources, for all the situations. A battery of sixteen anemometric probes and sixty four thermometric probes simultaneously recorded plume velocity and temperature distribution. These measurements allowed to determine the actual energy entrained by the plume above the source. Velocity measurements also allowed the plume flow rate to be evaluated. The evolution of ΔT c , the temperature difference between the maximum temperature and the ambient temperature for a given horizontal plane, yielded an approximation of the virtual origin that is in close agreement with the plume thermal and dynamic radii above the source. The values found for the flow rate and ΔT c are compared with those predicted by linear or point source formulae in order to determine an aspect ratio limit.

Low-Cost Ratiometric Front-End for Industrial PRT Applications

Cost, size, speed, and measurement range limitations make the resistance bridge not always suitable for temperature measurements with platinum resistance thermometers (PRTs) in industrial applications. However, high-accuracy resistance thermometer systems are often needed in many industrial applications, where measurement performances comparable to resistance bridges are often needed at a lower cost and size. A tiny, portable, ratiometric front-end exploiting a 24-bit analog-to-digital converter (ADC) with Σ Δ modulator is described. It was designed to measure the resistance ratio between a 100 Ω industrial PRT (IPRT) and a reference resistor with repeatability to within a few parts in 106. Its small size makes it ideal for integration in the stem-handle assembly of a thermometric probe, enabling an early transmission of measurement data in digital form. The ADC-based system design, development, and performance testing are discussed. The system was investigated in the resistance ratio range from about 4 × 10−3 to 5 × 10−2. Furthermore, a comparison between the system performance and a commercial AC resistance bridge was carried out and the results reported in this paper. An accurate thermometer for industrial applications resulted from the above developments. The compactness of the devices enabled an implementation of the ‘smart sensor’ concept in the measurement chain, where the front-end electronics was placed inside the IPRT handle together with an integrated memory to hold device identification, calibration coefficients, and the associated uncertainty. All data are transmitted to the readout module and are available to the user at a 5 Hz update rate for further analysis.