Application of the symbolic regression program AI-Feynman to psychology.

The discovery of hidden laws in data is the core challenge in many fields, from the natural sciences to the social sciences. However, this task has historically relied on human intuition and experience in many areas, including psychology. Therefore, discovering laws using artificial intelligence (AI) has two significant advantages. First, it makes it possible to detect laws that humans cannot discover. Second, it will help construct more accurate theories. An AI called AI-Feynman was released in a very different field, and it performed impressively. Although AI-Feynman was initially designed to discover laws in physics, it can also work well in psychology. This research aims to examine whether AI-Feynman can be a new data analysis method for inter-temporal choice experiments by testing whether it can discover the hyperbolic discount model as a discount function. An inter-temporal choice experiment was conducted to accomplish these objectives, and the data were input into AI-Feynman. As a result, seven discount function candidates were proposed by AI-Feynman. One candidate was the hyperbolic discount model, which is currently considered the most accurate. The three functions of the root-mean-squared errors were superior to the hyperbolic discount model. Moreover, one of the three candidates was more "hyperbolic" than the standard hyperbolic discount function. These results indicate two things. One is that AI-Feynman can be a new data analysis method for inter-temporal choice experiments. The other is that AI-Feynman can discover discount functions that humans cannot find.

Different properties of two types of red fluorescent proteins in octocoral, Scleronephthya spp. as Akane families.

We report the different properties of two types of red fluorescent proteins (RFP), undescribed species, extracted from two octocorals, Scleronephthya sp. 1 (S. sp. 1) and S. sp, 2 (Alcyonacea, Nephtheidae). S. sp. 1, named Alc-Orange, emits strong green emission at 492 nm and weak red emission at 590 and 630 nm when excited at 449 and 574 nm, respectively. S. sp. 2, LS-Red, emits strong deep red at 642 nm and weak green at 480 and 510 nm when excited at 574 nm and 434 nm, respectively. LS-Red has a very large Stokes shift of about 208 nm emitting at 642 nm when excited at 434 nm. Interestingly, LS-Red shows some emissions at 480 (blue emission), 514 (green emission), 563 (orange emission), and 642 nm (deep red emission) continuously at pH 7.5, which means multicolored fluorescence protein by one excitation at 434 nm. In pH dependence of fluorescence of Alc-Orange (pH 13 to 3.5), no relation between 'green and red FPs' was observed, whereas LS-Red showed the interconversion between 'green and red forms' depending on pH (11.5 to 4.5).

Does shift-and-persist strategy buffer career choice anxiety and affect career exploration?

OBJECTIVE: The transition from school to the workforce is important for concrete future planning. During this period, people are more likely to experience psychological health problems, such as anxiety and feelings of hopelessness and helplessness. In particular, job hunting in individuals with low socioeconomic status (SES) leads to various impulsive behaviors and physical and psychological problems due to a scarcity of economic and time resources. There is a lack of research examining career education and intervention approaches that consider the backgrounds of those experiencing adversities and difficulties due to low SES. Considering these situations, we examined whether shift-and-persist coping strategies (S-P) could buffer the career choice anxiety of individuals with low SES and improve career exploration. RESULTS: The results from 311 students who preparing/doing for job hunting showed a negative association between S-P and career choice anxiety and a positive association with career exploration. There are no significant effects of the direct link between SES to career exploration and the indirect link between SES and career exploration via career choice anxiety. There was also no buffering effect of S-P use on the above mediating process.

Exhausted parents in Japan: Preliminary validation of the Japanese version of the Parental Burnout Assessment.

We examined the factorial structure and validity of a Japanese version of the Parental Burnout Assessment, the PBA-J, with 1,500 Japanese parents. The Parental Burnout Assessment measures burnout using four dimensions: exhaustion in one's parental role, contrast in parental self, feelings of being fed up, and emotional distancing. Confirmatory factor analysis on the PBA-J supported a four-factor model. Multiple-group structural equation modeling with parent participants was supported for the factor-loading invariance model. Mothers had higher parental burnout scores than fathers. We found moderate-to-strong correlation coefficients between the PBA-J and the Parental Burnout Inventory (PBI-J; the comparative burnout measure), and weak-to-moderate correlation coefficients between the PBA-J and job burnout, neuroticism, co-parenting disagreement, and family disorganization. The PBA-J was correlated with parental perfectionism, particularly with concern over mistakes rather than sociodemographic variables. Overall, our findings provide initial evidence for the validity of the PBA-J.

Simple and rapid analysis of tocilizumab using HPLC-fluorescence detection method.

We developed a novel assay using high-performance liquid chromatography (HPLC) with fluorescence detection for the determination of tocilizumab (TCZ), after it has undergone a facile and rapid pretreatment. TCZ belongs to the same subclass as IgG1 (Immunoglobulin G subclass 1), and we could separate TCZ from IgG1 without antigen-antibody reactions, with the novel detection method. The separation of these antibodies was achieved by pretreatment with an organic solvent containing a base, such as trimethylamine and triethylamine. The effect of these bases on the separation of TCZ is related to the hydrophobicity of the base rather than the electrostatic charge. The results indicated that the surface charge of antibodies changed because of the structural change, even though the difference in the amino acid sequences of the antibodies was very low. Our method is available for the separation of the antibody subclasses, and it would be useful to assay TCZ in blood.

Quantification of three triterpenic acids in dried rosemary using HPLC-fluorescence detection and 4-(4,5-diphenyl-1H-imidazole-2-yl)benzoyl chloride derivatization.

Functional triterpenic acids such as ursolic acid (UA), oleanolic acid (OA) and betulinic acid (BA) are representative ingredients in rosemary that may have health benefits. UA, OA and BA in rosemary extracts were derivatized with 4-(4,5-diphenyl-1H-imidazole-2-yl)benzoyl chloride (DIB-Cl) and detected using HPLC-fluorescence (FL). Dried rosemary (50 mg) was ground, added to 3 ml of ethanol, sonicated for 40 min, then the sample solution was added to a mixture of 1% trimethylamine and 1 mM DIB-Cl in acetonitrile. The mixture was settled for 5 min at room temperature, then the DIB-triterpenic acid derivatives were separated using a Wakopak Handy ODS column (250 × 4.6 mm, 6 µm) eluted with 25 mM acetate buffer (pH 4.5)/methanol/acetonitrile (= 8:10:82 v/v/v%). The fluorescence intensity of the eluent was monitored at 365 (λex ) and 490 nm (λem ) and the maximum retention time of the derivatives was 30 min. Calibration curves constructed using rosemary extract spiked with standards showed good linearity (r ≥ 0.997) in the range 2.5-100 ng/ml. The detection limits at 3σ for internal BA, UA and OA peaks in rosemary extract were 0.2, 0.4 and 0.5 ng/ml, respectively. This method was used to quantify BA, UA and OA in commercially available dried rosemary products.

Preparation of Nanoparticles Including Antisolvent Drugs by the Combination of Roll Milling and High-pressure Homogenization.

DESCRIPTION: Design methods of nanoparticle formulations are divided into break-down methods and build-up methods. The former is further divided into dry and wet processes. For drug nanoparticle preparations, the wet process is generally employed, and organic solvents are used in most formulations. METHOD: In this study, we investigate the preparation of nifedipine (IB) and griseofulvin (GF) nanoparticles without using organic solvent. Both IB and GF nanoparticles, with a mean particle size of approximately 50 nm, were prepared without organic solvent by employing a combination of roll milling and high-pressure homogenization. RESULT: The X-ray diffraction peak of the IB and GF samples prepared by roll milling was present at a position (2θ) identical to that of IB and GF crystals, indicating that no peak shift was induced by interaction with phospholipids. CONCLUSION: These findings demonstrate that most IB and GF nanoparticles exist as crystals in phospholipids.

Physicochemical interaction mechanism between nanoparticles and tetrasaccharides (stachyose) during freeze-drying.

Nanoparticle suspensions are thermodynamically unstable and subject to aggregation. Freeze-drying on addition of saccharides is a useful method for preventing aggregation. In the present study, tetrasaccharides (stachyose) was employed as an additive. In addition, we hypothesize the interactive mechanism between stachyose and the nanoparticles during freeze-drying for the first time. The mean particle size of the rehydrated freeze-dried stachyose-containing nanoparticles (104.7 nm) was similar to the initial particle size before freeze-drying (76.8 nm), indicating that the particle size had been maintained. The mean particle size of the rehydrated normal-dried stachyose-containing nanoparticles was 222.2 nm. The powder X-ray diffraction of the freeze-dried stachyose-containing nanoparticles revealed a halo pattern. The powder X-ray diffraction of the normally dried stachyose-containing nanoparticles produced mainly a halo pattern and a partial peak. These results suggest an interaction between the nanoparticles and stachyose, and that this relationship depends on whether the mixture is freeze-dried or dried normally. In the case of normal drying, although most molecules cannot move rapidly thereby settling irregularly, some stachyose molecules can arrange regularly leading to some degree of crystallization and potentially some aggregation. In contrast, during freeze-drying, the moisture sublimed, while the stachyose molecules and nanoparticles were immobilized in the ice. After sublimation, stachyose remained in the space occupied by water and played the role of a buffer material, thus preventing aggregation.

Gender, Attitudes Toward War, and Masculinities in Japan.

Previous studies have argued that masculinity is linked to war. We conducted a web-based survey to examine relationships between gender, attitudes toward war, and masculinities within a sample of Japanese adults of both sexes ( N = 366). Our results indicated that while men were more likely than women to accept war, the relationship between attitudes toward war and masculinities was inconclusive. Moreover, the results suggested that favorable attitudes toward war among men could be attenuated by interpersonal orientations. Based on our findings, we recommend a reexamination of attitudes toward war within the Japanese population.

Luminol Chemiluminescence Profile of O/W Emulsions during Thermal Oxidation.

The luminol chemiluminescence (CL) profile of an oil-in-water (O/W) emulsion during thermal oxidation (60°C) was assessed using the luminol-K3[Fe(CN)6] assay, in which the oxidation species produced by the autoxidation of an O/W emulsion generated CL emission. Increased CL intensity was observed for O/W emulsions prepared using either linseed or corn oil, which was increased by the addition of Fe2+ to the O/W emulsion. The relationship between the CL profile and results obtained by conventional approaches, such as the peroxide value (PV) and thiobarbituric acid (TBA) methods, were compared. Owing to good correlation between the CL intensity and results obtained by the methods, the CL method might be applicable for estimating the oil oxidizing of an emulsion in thermal oxidation.

Quantitative and antioxidative behavior of Trolox in rats' blood and brain by HPLC-UV and SMFIA-CL methods.

Trolox, a water-soluble vitamin E analogue has been used as a positive control in Trolox equivalent antioxidant capacity and oxygen radical antioxidant capacity assays due to its high antioxidative effect. In this study, the ex vivo antioxidative effects of Trolox and its concentration in blood and brain microdialysates from rat after administration were evaluated by newly established semi-microflow injection analysis, chemiluminescence detection and HPLC-UV. In the administration test, the antioxidative effect of Trolox in blood and brain microdialysates after a single administration of 200 mg/kg of Trolox to rats could be monitored. The antioxidative effects in blood (12.0 ± 2.1) and brain (8.4 ± 2.1, × 10(3) antioxidative effect % × min) also increased. Additionally, the areas under the curve (AUC)s0-360 (n = 3) for blood and brain calculated with quantitative data were 10.5 ± 1.2 and 9.7 ± 2.5 mg/mL × min, respectively. This result indicates that Trolox transferability through the blood-brain barrier is high. The increase in the antioxidative effects caused by Trolox in the blood and brain could be confirmed because good correlations between concentration and antioxidative effects (r ≥ 0.702) were obtained. The fact that Trolox can produce an antioxidative effect in rat brain was clarified.

Validation of an LC-MS/MS Method for the Determination of Propofol, Midazolam, and Carbamazepine in Rat Plasma: Application to Monitor Their Concentrations Following Co-administration.

Propofol (PRO) is a hypnotic used to induce and maintain general anesthesia. A risk of drug-drug interactions exists in cases of clinical co-administration of PRO and midazolam (MDZ) or carbamazepine (CBZ). Therefore a sensitive and rapid assay is needed to monitor these drugs. In this study, a sensitive and selective liquid chromatography-tandem mass spectrometry technique was developed for simultaneous determination of PRO, MDZ, and CBZ in plasma. Simultaneous selected reaction monitoring in the positive and negative ionization modes was used for mass detection. Analytes were isolated from plasma samples by a simple, economic, and rapid solid-phase extraction method. Chromatographic separations were achieved using a Chromolith Performance RP-18e analytical column (100×4.6 mm i.d.) with a mixture of acetonitrile-ammonium acetate buffer (10 mM, pH 3.5) (90 : 10, v/v) as the mobile phase. The method was fully validated for PRO, MDZ, and CBZ over concentrations ranging at 1-100, 2-100, and 7-1000 ng/mL, respectively, with acceptable validation parameters. Furthermore, the method was applied to monitor PRO and MDZ or CBZ following co-administration in rats.

Simultaneous determination of propofol and remifentanil in rat plasma by liquid chromatography-tandem mass spectrometry: application to preclinical pharmacokinetic drug-drug interaction analysis.

Propofol (Pro) is an ultra-short-acting hypnotic agent used for general anesthesia that has no analgesic properties. Remifentanil (Rem) is an ultra-short-acting opioid administered concomitantly as an analgesic with Pro. To evaluate the pharmacokinetic interactions between Pro and Rem, we developed and validated a method combining high-performance liquid chromatography with tandem mass spectrometry for simultaneous determination of Pro and Rem. The proposed method was successfully used to study the pharmacokinetic interactions of Pro and Rem coadministered to rats.

Quantitation of sulfur-containing amino acids, homocysteine, methionine and cysteine in dried blood spot from newborn baby by HPLC-fluorescence detection.

Sulfur-containing amino acids (SAAs), homocysteine (Hcy), methionine (Met) and cysteine (Cys) in blood are related to homocystinuria, an inborn error of metabolism. In this study, an assay method with HPLC-fluorescence detection to quantify the SAAs in a dried blood spot was established and applied to samples from newborn babies (n=200). Sample pretreatment involving reduction, derivatization with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole, and liquid-liquid extraction with ethyl acetate gave the separation of the derivatives with retention times within 12 min. The method was enough sensitive to determine the SAAs in a dried blood spot with 0.04-0.14 µm as the limit of detection at a signal-to-noise ratio of 3. However, the absolute recoveries were very low (5.7% for Hcy, 4.6% for Cys) except for Met (105.4%) owing to inefficient recovery of Hcy and Cys from the blood matrix. Other validation parameters such as accuracy (93.5-106.2%) and intra- (≤ 9.0%) and inter-day precisions (≤ 8.7%) were acceptable. The reliability of a dried blood spot as an analytical sample was estimated. Furthermore, the proposed method was successfully applied to dried blood spots prepared from newborn babies.

The physicochemical interactive mechanism between nanoparticles and raffinose during freeze-drying.

New methods of preparing nanoparticles and in vivo studies of their behavior have been the subject of much study. However, there exist few studies on maintaining the nanoparticle size. In this work, we report on the interaction mechanism between raffinose and nanoparticles during freeze-drying. The mean particle size of the rehydrated freeze-dried raffinose-containing nanoparticles (170.5 nm) was similar to the initial particle size before freeze-drying (156.1 nm), indicating that the particle size was maintained. The powder X-ray diffraction of the freeze-dried raffinose-containing nanoparticles shows a halo pattern, while that of the normal-dried raffinose shows a crystalline pattern. No endothermic peak of the freeze-dried raffinose appeared, while the normal-dried raffinose had an endothermic peak at 84.0 °C. These results suggest that there exists a relationship between the nanoparticles and the raffinose, and that the relationship depends on whether the mixture is freeze-dried or normal-dried. In the case of normal drying, the raffinose molecules have space and time to arrange themselves into regular arrangement because the nanoparticles and raffinose molecules can move around freely in water. In contrast, in the case of freeze-drying, the moisture was sublimed while the raffinose molecules and nanoparticles were immobilized in the ice, thereby preventing aggregation.

Determination of folates by HPLC-chemiluminescence using a ruthenium(II)-cerium(IV) system, and its application to pharmaceutical preparations and supplements.

A chemiluminescence (CL) reaction of folic acid (FA) with ruthenium (II) and cerium (IV) was applied to quantify FA-related compounds such as FA, dihydrofolic acid, tetrahydrofolic acid, 5-methyltetrahydrofolic acid, 5-formyltetrahydrofolic acid and methotrexate (MTX). Among the FAs, 5-methyltetrahydrofolic acid provided the highest CL intensity. HPLC-CL detection of FA was applied to quantify FA in pharmaceutical preparations and supplements. Analytical samples were separated on a semi-micro ODS column with a mixture of 20 mM phosphate buffer (pH 5.7) and acetonitrile (94 : 6, v/v %). The separated samples were mixed with a post-column CL reagent consisting of 1.5 mM Ru(bipy)3 (2+) and 1.0 mM Ce(SO4)2 , then the generated CL was monitored. The calibration range for FA was 10-100 µM and the limit of detection was 1.34 µM (signal-to-noise ratio of 3). Repeatabilities were 4.2, 4.6 and 5.0 RSD% (10, 25, 50 µM), and the recoveries for FA supplement, vitamin B complex supplement and FA-containing medication (tablet) were 102.4 ± 10.5, 103.3 ± 13.3 and 100.3 ± 8.5%, respectively. The described method is robust against changes in the chromatographic parameters of ± 3.3 or ± 1.5%. The measured FA content corresponded well to the labeled content of FA-containing products (100.6-104.9%), demonstrating the precision and accuracy of this method for the evaluation of FA pharmaceutical preparations.

In vitro screening of Fe2+-chelating effect by a Fenton's reaction-luminol chemiluminescence system.

In vitro screening of a Fe(2+) -chelating effect using a Fenton's reaction-luminol chemiluminescence (CL) system is described. The luminescence between the reactive oxygen species generated by the Fenton's reaction and luminol was decreased on capturing Fe(2+) using a chelator. The proposed method can prevent the consumption of expensive seed compounds (drug discovery candidates) owing to the high sensitivity of CL detection. Therefore, the assay could be performed using small volumes of sample solution (150 µL) at micromolar concentrations. After optimization of the screening conditions, the efficacies of conventional chelators such as ethylenediaminetetraacetic acid (EDTA), diethylentriaminepentaacetic acid (DETAPAC), deferoxamine, deferiprone and 1,10-phenanthroline were examined. EC50 values for these compounds (except 1,10-phenanthroline) were in the range 3.20 ± 0.87 to 9.57 ± 0.64 µM (n = 3). Rapid measurement of the Fe(2+)-chelating effect with an assay run time of a few minutes could be achieved using the proposed method. In addition, the specificity of the method was discussed.

Development of a new evaluation method for gelatin film sheets.

Gelatin film sheets are often used to form the shell in soft capsules prepared using the rotary die method. Examination of the film sheet properties is extremely important when materials other than gelatin are used. We examined the relationship between the width and the tensile strength of the gelatin film sheet in order to establish the required indexes of the gelatin film sheets. The coefficients of correlation (R) of the linear regressions 4 and 15 min after preparation of the gelatin film sheets were 0.9858 and 0.9167, respectively. These results suggest that the tensile strength decreased when the width of the gelatin film sheet increased. Subsequently, we examined the relationship between time and the tensile strength. We observed new phenomenon: the tensile strength of the gelatin sheets increased with time, following two phases. The first phase corresponded to over phase transition point at 4, 8, and 15 min and the second phase corresponded to under transition point at 15, 30, and 60 min. The R values were 0.9952 (4, 8, 15 min) and 0.9494 (15, 30, 60 min).

Determination of the ratio between mercaptalbumin and nonmercaptalbumin by HPLC with fluorescence probe specifically binding to albumin.

A simple and selective HPLC-fluorescence (FL) method with FL probe, 4-[4-(4-dimethylaminophenyl)-5-phenyl-1H-imidazol-2-yl]benzoic acid methyl ester (DAPIM), for simultaneous determination of mercaptalbumin (HMA) and nonmercaptalbumin (HNA1) was developed. After HMA and HNA1 were separated on an ion-exchange column, they were on-line and post-column mixed with DAPIM. The DAPIM-albumin complex produces FL (λex 370nm and λem 510nm); however, DAPIM solution never gives the FL. Based on this mechanism, selective determination of HMA and HNA1 were achieved without any pretreatment and interfering peak. The proposed method was applied to the measurement of HMA and HNA1 in human serum of healthy volunteers and diabetes mellitus patients.

Rapid determination of isoamyl nitrite in pharmaceutical preparations by flow injection analysis with on-line UV irradiation and luminol chemiluminescence detection.

Isoamyl nitrite is used as a therapeutic reagent for cardiac angina and as an antidote for cyanide poisoning, but it is abused because of its euphoric properties. Therefore, a method to determine isoamyl nitrite is required in many fields, including pharmaceutical and forensic studies. In this study, a simple, rapid and sensitive method for the determination of isoamyl nitrite was developed using a flow injection analysis system equipped with a chemiluminescence detector and on-line photoreactor. This method is based on on-line ultraviolet irradiation of isoamyl nitrite and subsequent luminol chemiluminescence detection without the addition of an oxidant. A linear standard curve was obtained up to 1.0 µM of isoamyl nitrite with a detection limit (blank + 3SD) of 0.03 µM. The method was successfully applied to determine isoamyl nitrite content in pharmaceutical preparations.