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Serotonin 5-HT 1A receptor agonists increase locomotor activity of both preweanling and adult rodents. The part played by the 5-HT 1B receptor in locomotion is less certain, with preliminary evidence suggesting that the actions of 5-HT 1B receptor agonists are not uniform across ontogeny. To more fully examine the role of 5-HT 1B receptors, locomotor activity and axillary temperatures of preweanling and adult male and female rats was assessed. In the first experiment, adult (PD 70) and preweanling (PD 10 and PD 15) male and female rats were injected with the 5-HT 1B agonist CP 94253 (2.5-10 mg/kg) immediately before locomotor activity testing and 60 min before axillary temperatures were recorded. In the second experiment, specificity of drug action was determined in PD 10 rats by administering saline, WAY 100635 (a 5-HT 1A antagonist), or GR 127935 (a 5-HT 1B antagonist) 30 min before CP 94253 (10 mg/kg) treatment. CP 94253 significantly increased the locomotor activity of preweanling rats on PD 10, an effect that was fully attenuated by GR 127935. Conversely, CP 94253 significantly decreased the locomotor activity of male and female adult rats, while CP 94253 did not affect the locomotor activity of PD 15 rats. Regardless of age, CP 94253 (2.5-10 mg/kg) significantly reduced the axillary temperatures of preweanling and adult rats. When considered together, these results show that 5-HT 1B receptor stimulation activates motor circuits in PD 10 rats; whereas, 5-HT 1B receptor agonism reduces the overall locomotor activity of adult rats, perhaps by blunting exploratory tendencies., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Rationale: Drugs that stimulate 5-HT 1A/1B receptors produce both tolerance and behavioral sensitization in adult rats and mice, yet it is unknown whether the same types of plasticity are evident during earlier ontogenetic periods., Objective: The purpose of this study was to determine whether repeated treatment with selective 5-HT 1A and/or 5-HT 1B agonists cause tolerance and/or sensitization in preweanling rats., Methods: In Experiments 1 and 2, male and female preweanling rats were given a single pretreatment injection of saline, the 5-HT 1A agonist (R)-( +)-8-hydroxy-DPAT (8-OH-DPAT), or the 5-HT 1B agonist CP-94253 on PD 20. After 48 h, rats received a challenge injection of 8-OH-DPAT or CP-94253, respectively. In Experiment 3, rats were pretreated with saline or DPAT + CP on PD 20 and challenged with the same drug cocktail on PD 22. In Experiment 4, the tolerance- or sensitization-inducing properties of 8-OH-DPAT, CP-94253, or DPAT + CP were tested after a 4-day pretreatment regimen on PD 17-20., Results: On the first pretreatment day, 8-OH-DPAT, CP-94253, and DPAT + CP increased locomotion and caused hypothermia. Repeated treatment with 8-OH-DPAT (2 or 8 mg/kg) or DPAT + CP caused locomotor sensitization in preweanling rats. In contrast, tolerance to the hypothermic effects of 8-OH-DPAT (8 mg/kg), CP-94253 (5-20 mg/kg), or DPAT + CP was evident after repeated drug treatment., Conclusions: During the preweanling period, a single injection of a selective 5-HT 1A or 5-HT 1B agonist is capable of producing drug-induced plasticity. A pretreatment administration of 8-OH-DPAT causes both tolerance (hypothermia) and behavioral sensitization (locomotor activity) in preweanling rats, whereas repeated CP-94253 treatment results in tolerance., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The integrated analytical approach developed in this study offers a powerful methodology for the structural characterisation of complex molecular nanomaterials. Structures of a covalent organic framework based on boronate esters (COF-5) and a conjugated microporous polymer (Aza-CMP) have been investigated by a combination of several electron microscopy techniques elucidating the three-dimensional topology of the complex polycrystalline (COF) and non-crystalline (CMP) materials. Unexpected, aperiodic mesoporous channels of 20-50 nm in diameter were found to be penetrating the COF and CMP particles, which cannot be detected by X-ray diffraction techniques. The mesopores appear to be stable under a range of different conditions and accessible to gas molecules, exhibiting a particular bonding capability with CO2 in the case of the CMP. The mesoporosity is unrelated to the intrinsic chemical structures of the COF or CMP but rather it reflects the mechanisms of polymer particle formation in a polycondensation reaction. The mesopores may be templated by clusters of solvent molecules during the COF or CMP synthesis, leaving cavities within the polymer particles. The unexpected mesoporosity discovered in COF and CMP materials begs for re-assessment of the nature of framework materials and may open new opportunities for applications of these molecular materials in gas sorption or catalysis.

In this contribution, the effect of silica particle size (28 and 210 nm) and surface chemistry (i.e., hydroxyl, methyl, or amino groups) on peptide binding response is studied with a specific emphasis on the effect of the extent of functionalization on binding. Exhaustive characterization of the silica surfaces was crucial for knowledge of the chemistry and topography of the solid surface under study and, thus, to understand their impact on adsorption and the conformational ensemble of the peptides. The extent of surface functionalization was shown to be particle-size dependent, a higher level of 3-aminopropyl functionality being obtained for smaller particles, whereas a higher degree of methyl group functionality was found for the larger particles. We demonstrated that peptide interactions at the aqueous interface were not only influenced by the surface chemistry but also by the extent of functionalization where a "switch" of peptide adsorption behavior was observed, whereas the changes in the conformational ensemble revealed by circular dichroism were independent of the extent of functionalization. In addition to electrostatic interactions and hydrogen bonding driving interaction at the silica-peptide interface, the data obtained suggested that stronger interactions such as hydrophobic and/or covalent interactions may moderate the interaction. The insights gained from this peptide-mineral study give a more comprehensive view of mechanisms concerning mineral-peptide interactions which may allow for the design and synthesis of novel (nano)materials with properties tailored for specific applications.

Psychological tests sometimes include figurative language like I feel blue. However, figurative language may not mean the same thing cross-culturally. Previous research found cross-cultural evidence for 14 conceptual metaphors and metonymies for emotions (e.g., sadness is blue). Our two studies asked participants (total n = 795) in the USA and India whether happiness, sadness, anger, and fear are associated with certain descriptors (blue, down, bright, etc.). Most participants in both countries endorsed ten of the 14 hypothesized associations; however, the percentage of participants endorsing an association was often far from 100 %. For example, in the USA, only 71.7 % associated hot with anger and only 65.9 % associated blue with sadness. Moreover, descriptors were often associated with more than one emotion. Furthermore, only two associations (happiness is up and bright) were endorsed by more than 90 % of participants in both countries and had descriptors that were not associated with additional emotions. We conclude that figurative language is often ambiguous and should be used with caution on psychological tests unless there is evidence the language is understood cross-culturally. Advice to this effect is currently lacking from psychometrics textbooks and should be added.

Biomolecule-mediated synthesis is fascinating in terms of the level of control and the intricate hierarchical structures of the materials that can be produced. In this study we compare the behavior of a phage display identified peptide, EAHVMHKVAPRP (EM-12) with that of a mutant peptide EAHVCHKVAPRP (EC-12), having additional complexation capability, on the formation of ZnO from solution. The synthesis conditions (Zn(CH 3 COO) 2 -NH 3 hydrothermal method at 50 °C) were chosen to generate rod-shaped ZnO via layered basic zinc salts (LBZs) as intermediates. Both peptides affected the crystal formation process by moderating the amount of Zn 2+ ions in solution (EC12 having a greater effect than EM12) but only EC12 was shown to interact with the solid phase(s) formed during the reaction. Depending on the peptide concentration used, EM-12 was shown to delay and/or suppress ZnO formation. In contrast, additions of EC-12, although leading to the retention of higher levels of Zn 2+ ions in solution did not similarly delay the transformation of the intermediate phases to ZnO but were found to dramatically modify the morphology of ZnO crystallites with mushroom shaped crystals being formed. From the results of detailed materials characterization and changes in the morphology observed, the interactions between the peptide(s) and solution and solid state species present during the process of ZnO crystal formation in the presence of EM-12 and EC-12 are proposed.

Single-crystalline hexagonal alpha-Fe(2)O(3) nanorods/nanobelts have been created by a simple iron-water reaction in the low-temperature range of 350-450 degrees C. Scanning electron microscopy examination shows that the needle-like products, radiating from and perpendicular to the original large iron particle surfaces, are up to a few micrometers in length with an average diameter from 20 nm (tip) to 100 nm (base). X-ray photoelectron spectroscopy and FTIR spectroscopy reveal that the outermost surface of the nanorods consists of Fe(2)O(3) without organic impurity contaminants, which could possibly result from other methods, such as hydrothermal growth. Nanobelt-like structures are believed to result from a combination of increased reaction temperature and time. The initial formation and subsequent growth of alpha-Fe(2)O(3) nanorods may be explained by the iron metal corrosion mechanism.

The excellent shock-absorbing performance of WS2 and MoS2 nanoparticles with inorganic fullerene-like structures (IFs) under very high shock wave pressures of 25 GPa is described. The combined techniques of X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, thermal analysis, and transmission electron microscopy have been used to evaluate the diverse, intriguing features of shock recovered IFs, of interest for their tribological applications, thereby allowing improved understanding of their antishock behavior and structure-property relationships. Two possible failure mechanisms are proposed and discussed. The supershock-absorbing ability of the IF-WS2 enables them to survive pressures up to 25 GPa accompanied with concurrent temperatures of up to 1000 degrees C without any significant structural degradation or phase change making them probably the strongest cage molecules now known.

Chromite ore processing residue (COPR), derived from the so-called high lime processing of chromite ore, contains high levels of Cr(III) and Cr(VI) and has a pH between 11 and 12. Ferrous sulfate, which is used for remediation of Cr(VI) contamination in wastewater and soils via reduction to Cr(III) and subsequent precipitation of iron(III)/chromium(III) hydroxide, has also been proposed for remediation of Cr(VI) in COPR. Instead, however, addition of FeSO4 to the infiltrating solution in column experiments with COPR greatly increased leaching of Cr(VI). Leached Cr(VI) increased from 3.8 to 12.3 mmol kg(-1) COPR in 25 pore volumes with 20 mM FeSO4, reaching solution concentrations as high as 1.6 mM. Fe(II) was ineffective in reducing Cr(VI) to Cr(III) because it precipitated when it entered the column due to the high pH of COPR, while Cr(VI) in solution was transported away with the infiltrating solution. The large increase in leaching of Cr(VI) upon infiltration of sulfate, either as FeSO4 or Na2SO4, was caused by anion exchange of sulfate for chromate in the layered double hydroxide mineral hydrocalumite, a process for which scanning electron microscopy with energy-dispersive X-ray microanalysis provided direct evidence.

A range of techniques, normally associated with mineralogical studies of soils and sediments, has been used to characterise the solid materials found on sites contaminated with chromite ore processing residue (COPR). The results show that a wide range of minerals are present, many of which are found extensively in high-temperature synthetic systems such as cements and clinkers and their low temperature hydration products. Thus, the minerals in COPR can be divided into three main categories: unreacted feedstock ore (chromite); high temperature phases produced during chromium extraction (brownmillerite, periclase and larnite); and finally, minerals formed under ambient weathering conditions on the disposal sites (brucite, calcite, aragonite, ettringite, hydrocalumite, hydrogarnet). Apart from chromite, chromium occurs in brownmillerite, ettringite, hydrocalumite and hydrogarnet. Detailed study of the chemistry and stoichiometry of chromium-bearing phases in conjunction with phase abundance provides a quantitative description of the solid state speciation of Cr(III) and Cr(VI) in and amongst these minerals and in the COPR as a whole. Of the total chromium present in the samples most, approximately 60-70% is present as Cr(III) in chromite, whilst brownmillerite also represents a significant reservoir of Cr(III) which is approximately 15% of the total. The remaining chromium, between 20 and 25%, is present as Cr(VI) and resides mainly in hydrogarnet, and to a slightly lesser extent in hydrocalumite. In the latter, it is present principally in an exchangeable anionic form. Chromium (VI) is also present in ettringite, but quantitatively ettringite is a much less important reservoir of Cr(VI), accounting for approximately 3% of total chromium in one sample, but less than 1% in the other two. This description provides insight into the processes likely to control the retention and release of Cr(VI) from COPR-contaminated sites. Such information is of particular value in chemical modelling of the system, in risk assessment and in the development of methods of informed remediation.

The primary purpose of the study was to determine whether pen users would challenge the insufficient remaining dose (IRD) stop mechanism with sufficient force to affect the dose accuracy of the final dose. The secondary purpose was to determine the participant's positive and negative impressions of the Humalog/Humulin pen and the likelihood of using the new prefilled pen. Three different modifications to the prefilled pen's IRD stop feature were made. These three pen models then underwent environmental dose accuracy testing at various temperatures and humidities, and user dose accuracy testing by 64 patients with diabetes. Evaluation also involved challenging the IRD stop at various dialing torques. Thirty pens from each model were tested to failure of the IRD stop. A model of the prefilled pen was selected for commercialization that met the dose accuracy targets of +/- 1 unit (U) for insulin doses less than 20 U and +/- 5% of dose volume for doses equal to or over 20 U. The selected pen model was superior at the minimum (1 unit), median (30 unit) and maximum (60 unit) dose volumes. Also 92% (n = 59) of patients interviewed felt that the stop mechanism for the final dose was clear. Extensive testing in the development of a prefilled insulin delivery device demonstrates an accurate and reliable medical device.

To study the cardiovascular responses to selective activation of neuronal cell bodies in the hypothalamus, DL-homocysteate (5-50 nl of a 0.15-M solution, pH 7.4) was injected into 417 histologically verified sites in the hypothalamus of 46 urethan-anesthetized, paralyzed and artificially ventilated rats. Injections resulted in depressor responses (-5 to -32 mm Hg) in 271 sites, in pressor responses (5-47 mm Hg) in 77 sites and 69 sites were not responsive. Depressor effects had a shorter latency (85% started within 5 s) than pressor effects (42% started within 5 s). Control injections of 0.15 M NaCl into 126 of the responsive sites were ineffective. Arterial pressure (AP) responses showed a positive correlation (r = 0.61, P less than 0.001) with changes in heart rate (HR). Analysis of the anatomical distribution of responsive sites showed that in all hypothalamic subdivisions depressor responses predominated except in the paraventricular nucleus, where mainly pressor effects and tachycardia were elicited. These results demonstrate that excitation of cell bodies in most hypothalamic regions elicits neurally mediated changes in AP and HR and that the traditional functional division of the hypothalamus into a rostral depressor and a caudal pressor area is probably based on the combined excitation of fibers of passage and cell bodies.