藥物作用の温度係數に關する研究

Some considerations of measuring temperature sensitivity in thermal ecology

A curvature-compensated CMOS voltage reference using [formula omitted] characteristics

The use of reduced intrathecal doses is advised for spinal anesthesia during cesarean delivery. However, there are inadequate data regarding the minimum effective dose of intrathecal bupivacaine for cesarean delivery. Preeclampsia is caused by an endothelial dysfunction leading to generalized vasoconstriction. Whether this can offset the pregnancy-induced decrease in intrathecal dose requirement caused by epidural venous dilation and consequent thecal compression is not known. There are no data to evaluate the minimum effective dose of intrathecal drug for cesarean delivery in preeclamptic patients. This study aimed to determine the minimum effective dose represented by the ED50 of intrathecal hyperbaric bupivacaine for normotensive and severely preeclamptic patients undergoing elective cesarean delivery. Combined spinal epidural anesthesia was administered using a standardized technique on 18 consecutively preeclamptic and normotensive patients, each carrying an otherwise uncomplicated singleton pregnancy. The dose of intrathecal hyperbaric bupivacaine was decided by using the up-and-down method with an initial dose of 9 mg and dosing change of 1 mg. All patients received 20 μg of fentanyl intrathecally with bupivacaine. A successful block was defined as one that resulted in a sensory block to T4 level with modified Bromage score of 1 or 2 within 15 minutes of intrathecal injection. ED50 of intrathecal hyperbaric bupivacaine was identical in severely preeclamptic and normotensive parturients undergoing elective cesarean delivery (4.7 mg; 95% confidence interval, 4.5-4.9 mg). When a combined-spinal epidural is planned in normotensive or severely preeclamptic patients for an elective cesarean delivery, the ED50 of intrathecal hyperbaric bupivacaine along with 20 μg of fentanyl is 4.7 mg.

Int J Obstet Anesth. 2024;57:103962. https://doi.org/10.1016/j.ijoa.2023.103962 A leading cause of maternal morbidity and mortality, with uterine atony being the primary factor, is postpartum hemorrhage (PPH). The administration of oxytocin, used as the first-line prophylactic to prevent uterine atony during cesarean delivery (CD), varies in dose, timing, and duration across clinical practices. Lower oxytocin doses are often used to minimize maternal side effects linked to high-dose boluses or empirically titrated infusions. With rising obesity rates and significant pregnancy weight gain, higher oxytocin doses are required for labor induction and augmentation in obese patients. Research indicates obesity may reduce oxytocin-induced myometrial contractility. Despite this, only one study has evaluated the optimal oxytocin dose in patients with a BMI ≥40 kg/m2 undergoing CD, highlighting a need for more research. The study aims to determine the minimum effective oxytocin infusion dose for adequate uterine tone in obese patients, comparing it with a control group of nonobese patients.

A novel design for temperature-compensated CMOS voltage reference sources by using the 1st order voltage reference taking into account the property of the conventional current generator is proposed to minimize the temperature coefficient because the 2nd order voltage reference obtained by the compensated nonlinearity of the base-emitters in complementary to absolute temperature has inherent complex problems due to the large scale circuits. A temperature coefficient of the proposed voltage reference source is estimated by using the current generator, which operates at smaller or larger temperature in comparison with the optimized operating temperature. The proposed temperature-compensated CMOS voltage reference sources are simulated by using a SMIC 0.35 gm CMOS technology. The temperature coefficient, obtained from the SMIC 0.35 μm CMOS technology, is 8.35 ppm/°C in a temperature range between ’40 and 125°C. The simulated results indicate that the proposed temperature-compensated CMOS voltage reference sources by using the 1 st order voltage reference taking into account the property of the conventional current generator can be used to decrease the temperature coefficient.

In February 2012 the Rondegat River, in the Cape Floristic Region, was the first river in South Africa where the piscicide rotenone was used to remove an alien invasive fish, smallmouth bass Micropterus dolomieu. In preparation for this treatment, the sensitivity of smallmouth bass to various concentrations of the rotenone formulation CFT Legumine (5% active rotenone) was evaluated a week prior to treatment using standard toxicity tests to determine the minimum effective dose (MED) that would result in 100% mortality after exposure for 4 h. The MED was 0.0125 mg l-1 rotenone. Adverse effects, including erratic swimming, loss of equilibrium and death, occurred in a dose-dependent manner with smaller fish responding faster than larger ones. Standard operating procedures for the use of rotenone recommend treatment at a minimum of twice the calculated MED. Given the uncertainty associated with rotenone losses through hydrolysis and photolysis under field conditions, and the possible occurrence of smallmouth bass more tolerant than those tested, a concentration of twice the recommended treatment dose (0.050 mg l-1 rotenone) was finally used to treat the Rondegat River for a duration of 6 h.

Tramadol is a potent analgesic. However, the analgesia efficacy of tramadol, particularly its minimum effective dose (MED), is not clear. The aim of this study is to find MED of tramadol for postoperative analgesia in infants. The continual reassessment method (CRM) was performed to find MED. Infants undergoing surgeries were included in the 3 phases of this series. In each phase, 24 participants were allocated a different tramadol dose. Pain intensity was measured by face, legs, activity, cry, consolability (FLACC) measurement at 3-hour intervals. Tramadol was considered ineffective if the FLACC score was higher than 4 in 10 at anytime. In phase 1, seven dose levels were used within the range 0.1-0.4 mg·kg(-1)·h(-1). Phase 1 was insufficient to identify the MED, and we increased the dose to 0.4-0.8 mg·kg(-1)·h(-1) in phase 2. Phase 2 was insufficient to identify the MED. In phase 3, local anesthetic wound infiltration was introduced, and the tramadol dose levels tested were the same as in phase 1. The successful analgesia probability of tramadol 0.4 mg·kg(-1)·h(-1) was 82.1% (95% CI, 0.742-0.925) in phase 1. In phase 2, it was 84.7% (95% CI, 0.789-0.991) with the dose 0.8 mg·kg(-1)·h(-1). Phase 1 and phase 2 were insufficient to identify the MED. In phase 3, the successful analgesia probability for dose 0.35 mg·kg(-1)·h(-1) was 96.7% (95% CI, 0.853-0.997).We have demonstrated that tramadol provides insufficient analgesia for surgeries considered to cause moderate-to-severe postoperative pain in infants if used as the sole analgesic, and that local anesthetic wound infiltration enhances the efficacy of tramadol.

An important application of thin-film hydrogenated amorphous silicon (α-Si:H) is infrared detection and imaging with microbolometer focal plane arrays. Key α-Si:H electrical transport properties that influence detector design and performance are resistivity and temperature coefficient of resistance (TCR). These properties have been measured over a wide temperature range for p- and n-type doped α-Si:H thin-films deposited by plasma enhanced chemical vapor deposition using silane as a precursor gas. Resistivity near and above room temperature follows an Arrhenius thermally activated dependence. At low temperatures, resistivity transitions from Arrhenius behavior to a variable range hopping mechanism described by the Mott relation and TCR changes at a slower rate than predicted by thermally activated transport alone. Resistivity and TCR are affected by doping and film growth parameters such as dilution of the silane precursor with hydrogen. Resistivity decreases with dopant concentration for both p-type and n-type dopants. Resistivity and TCR increase with hydrogen dilution of silane. TCR and resistivity are interrelated and optimization of thin-film preparation and processing is necessary to obtain high TCR with resistivity values compatible with readout integrated circuit designs. Such optimization of transport properties of α-Si:H films has been applied to the development of high performance ambient operating temperature (uncooled) microbolometer arrays.

In this paper we propose a procedure based on the Mott variable-range hopping model that describes the low-temperature conduction in strongly disordered systems such as negative temperature coefficient (NTC) thermistors. This procedure offers a close approximation to the physical model and provides an accurate R ( T ) fit for the resistance − temperature data over three orders of magnitude temperature range (0.04 K — 40 K) using only 4 fit coefficients. Eventually, the temperature corresponding to any resistance value of the thermistor T ( R ) can be determined with an approximation of an inverted R ( T ) function based on a Puiseux series expansion. This approach has been showed to be applicable to different NTC thermistors, including ruthenium oxide (RuO 2 ) and germanium (Ge) resistors with a range of resistance values. It provides a root mean square of the relative residual of the fit Δ T rel RMS ≤ 1 % and Δ T rel RMS ≤ 1 . 7 % using a n fit ∈ [ 4 , 10 ] and n fit = 4 fit coefficients for RuO 2 and Ge, respectively. Previously reported procedures for the calibration of resistance-temperature data in low-temperature thermistors do not reach this accuracy with a similar number of fit coefficients. • We report on a comprehensive calibration procedure to fit resistance-temperature data set providing the R ( T ) function and its inversion T ( R ) • The R ( T ) function is derived from Mott variable-range hopping which describes the low temperature carrier transport in disordered semiconductors in an extended temperature range. The T ( R ) function is approximated using Puiseux series expansion. • This calibration procedure has been tested on different NTC thermistors over three orders of magnitude of temperature range (40 mK to 40 K). • This calibration procedure reports a root mean square of the relative residual of the fit Δ T rel RMS ≤ 1 % and Δ T rel RMS ≤ 1 . 7 % using a number of fit coefficients n fit ∈ [ 4 , 10 ] and n fit = 4 for RuO 2 and Ge, respectively. None of the common calibration equations can reach such a level of accuracy over the specified temperature range with the same number of fit coefficients. • Calibration precision doesn’t degrade but remains stable when more fit coefficients are added, as it happens, for instance, to the expansion series of the Basic Equation.

Low-temperature (300–4.2 K) electrical resistivity behaviours of as-cast glassy, relaxed, and crystallizedPd40Ni10Cu30P20 alloys have been investigated. It is found that the resistivity of the as-cast glassy alloy is about257 µΩ cm at ambient temperature and decreases with a temperature coefficient of resistivity (TCR) of2.1 × 10−4 K−1 in the temperaturerange of 280–50 K and 89 × 10−4 K−1 in the temperature range of 12–4.2 K. The relaxation effect slightly increases the resistivityby a factor of about 10% while crystallization decreases the resistivity of the alloy.Surprisingly, we found that all samples, as-cast glassy, relaxed, crystallized, andwell-crystallized alloys, exhibit similar temperature dependences of the electricalresistivity in the temperature range investigated. TCR changes at around 10–20 Kfor all samples are linked with rapid increase of the magnetization in the alloys.

Designing alloys with an accurate temperature-independent electrical response over a wide temperature range, specifically a low temperature coefficient of resistance (TCR), remains a big challenge from a material design point of view. More than a century after their discovery, Constantan (Cu-Ni) and Manganin (Cu-Mn-Ni) alloys remain the top choice for strain gauge applications and high-quality resistors up to 473-573 K. Here, an average TCR is demonstrated that is up to ≈800 times smaller in the temperature range 5-300 K and >800 times smaller than for any of these standard materials over a wide temperature range (5 K < T < 1200 K). This is achieved for selected compositions of Alx CoCrFeNi high-entropy alloys (HEAs), for which a strong correlation of the ultralow TCR is established with the underlying microstructure and its local composition. The exceptionally low electron-phonon coupling expected in these HEAs is crucial for developing novel devices, e.g., hot-electron detectors, high-Q resonant antennas, and materials in gravitational wave detectors.

To determine the minimum effective dose and safety of micafungin in the treatment of HIV-related oesophageal candidiasis. A total of 120 patients were enrolled in this open label study of the effects of daily 1 h infusions of micafungin on endoscopically proven fungal oesophagitis. Patients were randomly assigned to receive 12.5, 25, 50, 75 and 100 mg of micafungin daily. Response was evaluated clinically and endoscopically. The protocol defined minimum effective dose of micafungin was 12.5 mg. The percentage of patients experiencing clearing of physical signs and symptoms showed a dose-response relationship and reached 94.7% in the 100 mg dose group. All patients in the 50, 75 and 100 mg dose groups achieved an endoscopically verified improvement in oesophagitis. Adverse effects of micafungin were generally mild and not dose-related. No serious renal, hepatic or drug-related infusion reactions were encountered. Micafungin was found to be effective, well-tolerated and safe. The minimum effective dose was found to be 12.5 mg and a significant linear trend in the successful treatment of oesophageal candidiasis was observed across the doses used with 75 and 100 mg dose levels achieving high rates of clinical and endoscopic cure.

Chemical instrumentation: A systematic approach to instrumental analysis: by H. A. Strobel. 653 pages, diagrams, 6 × 9 in. Reading (Mass), Addison-Wesley Publishing Co., Inc., 1960. Price, $9.75

The synthetic prostaglandin SC‐46275, an omega‐chain cyclopentenyl analogue of enisoprost, has been studied in the rat to determine its suitability for development as an anticulcer agent. In the pylorus ligated (Shay) model, SC‐46275 exhibited more potent antisecretory activity when administered intragastrically than when administered intraduodenally, the minimal effective doses (M.E.D.) being, respectively, 10 and 100 μg/kg. Intragastric administration of SC‐46275 significantly (P ≤ 0.05) reduced the number (M.E.D. 2.5 μg/kg) and length (M.E.D. 5 μg/kg) of ethanol‐induced gastric lesions. It was also active intragastrically (M.E.D. 0.3 μg/kg) against indomethacin‐induced intestinal damage. Interestingly, SC‐46275 had no effect on the incidence of indomethacin‐induced intestinal damage when given intragastrically and significantly reduced the severity of damage only at the highest dose tested, 300 μg/kg. SC‐46275, was less diarrheagenic than misoprostol when given intraduodenally; it was even less diarrheagenic when given intragastrically, being virtually devoid of diarrheagenic activity at a dose 300 times greater than the antisecretory dose. These data indicate that SC‐46275, a potent, possibly locally active gastric antisecretory, mucosal‐protective prostaglandin possessing minimal diarrheagenic activity, may be useful in the treatment of gastric/duodenal ulcer disease.

The properties of a quasicrystalline phase in the Al-Pd-Tc system are studied for the first time. X-ray investigations demonstrate that the quasicrystalline phase in the Al70Pd21Tc9 alloy has a face-centered icosahedral quasi-lattice with parameter a=6.514 A. Annealing experiments have revealed that this icosahedral phase is thermodynamically stable. The heat capacity of an Al70Pd21Tc9 sample is measured in the temperature range 3–30 K. The electrical resistivity and magnetic susceptibility are determined in the temperature range 2–300 K. The electrical resistivity is found to be high (600 µΩ cm at room temperature), which is typical of quasicrystals. The temperature coefficient of electrical resistivity is small and positive at temperatures above 50 K and negative at temperatures below 50 K. The magnetic susceptibility has a weakly paramagnetic character. The coefficient of linear contribution to heat capacity (γ=0.24 mJ/(g-atom K2)) and the Debye characteristic temperature (Θ=410 K) are determined. The origin of the specific features in the vibrational spectrum of the quasicrystals is discussed.