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A new 3D metal–organic framework (MOF), in which 2D layers are interlaced to form a 3D architecture, was synthesized by a reaction of Cu(BF4)2 and 1,3-bis(4-pyridyl)propane (bpp) in a water/1-hexanol solvent system, and the crystal structure of the MOF was successfully solved. The MOF is reversibly transformed to a 1D chain MOF, which shows gate adsorption properties. The dynamic transformation gives crystal size reduction resulting in a slight change in CO2 adsorption isotherms. The 1D MOF shows selective adsorption/separation properties on benzene and its analogues with similar sizes and shapes (benzene, toluene, and cyclohexane). [ABSTRACT FROM AUTHOR]

Conclusions: Hydrostatic positive pressure and vasoconstrictor acidified the cochlear fluids, whereas the vasodilator made the fluids alkaline. CBF might play a role in regulating cochlea fluid pH. Objectives: Cochlea fluid pH is highly dependent on the HCO3−/CO2 buffer system. Cochlear blood flow (CBF) supplies O2 and removes CO2. It is speculated that cochlear blood flow changes might affect the balance of the HCO3−/CO2 buffer system in the cochlea. It is known that the elevation of inner ear pressure decreases the CBF, and local application of vasodilating or vasoconstricting agents directly to the cochlea changes the CBF. The purpose of this study was to elucidate the effect of positive hydrostatic inner ear pressure and application of a vasodilator and vasoconstrictor of cochlear vessels on the pH of the endolymph and perilymph. Methods: The authors performed animal physiological experiments on 30 guinea pigs. Hydrostatic positive pressure was infused through a glass capillary tube inserted into the scala tympani of the basal turn. The vasodilator, nitric oxide donor (sodium nitroprusside; SNP), and the vasoconstrictor, bupivacaine, were placed topically onto the round window of the guinea pig cochlea. Endolymph pH (pHe) and endocochlear potential (EP) were monitored by double-barreled ion-selective microelectrodes in the second turn of the guinea pig cochlea. During the topical application study, scala vestibuli perilymph pH (pHv) was also measured simultaneously in the second turn. Results: The application of hydrostatic positive pressure caused a decrease in pHe and EP. Positive perilymphatic pressure caused the endolymph to become acidic pressure-dependently. Application of 3.0% SNP evoked an increase in both the pHe and pHv, following by a gradual recovery to baseline levels. On the other hand, 0.5% bupivacaine caused a decrease in both the pHe and pHv. The EP during topical application showed slight, non-significant changes. [ABSTRACT FROM AUTHOR]

The crystal structure of Al3O3.5C0.5 (Z = 3) has been characterized by X-ray powder diffraction (XRPD), transmission electron microscopy, and electron probe microanalysis. The tide compound is trigonal with space group R3m (centrosymmetric) and hexagonal unit-cell dimensions a = 0.29588(1) nm, c = 2.84080(7) nm, and V = 0.21538(1) nm³. The initial structural model was determined by the charge-flipping method and subsequently refined by the Rietveld method. The final structural model showed the positional disordering of one of the two types of Al sites. The maximum-entropy method-based pattern fitting (MPF) method was used to confirm die validity of the split-atom model, in which conventional structure bias caused by assuming intensity partitioning was minimized. The reliability indices calculated from the MPF were Rwp - 4.03%, S (= Rwp/Rc) = 1.17, Rp = 3.08%, RB = 0.82%, and RF = 0.72%. The crystal was composed of antiphase domains, suggesting the occurrence of the high-low phase transition during the cooling process. The transition would be accompanied by the loss of unit-lattice translation, and hence the disordered structural model determined by XRPD might be of the average structure of the low-temperature phase. [ABSTRACT FROM AUTHOR]

Iodine concentration and radioisotopic composition (129I/I) were measured in the pore waters from the gas hydrate occurrence in the forearc basin offshore Shimokita Peninsula, north-eastern Japan, to determine the source formation of I and accompanying hydrocarbons. Iodine concentrations correlate well with the alkalinity and SO4 patterns, reflecting degradation stages of I-rich buried organic matter, rapidly increasing in the sulfate reduction interval, and becoming constant below 250 meters below the seafloor with an upwelling flux of 1.5 × 10−11 µmol cm−2 year−1. The 129I/I ratios of 300 × 10−15–400 × 10−15 in deep pore waters suggest ages for iodine and hydrocarbon sources as old as 40 Ma. These ages correlate well with the coaly source formations of the Eocene age thought to be responsible for the conventional natural gas deposits underlying the gas hydrate stability zone. Similar profiles are observed in 129I/I ratios of pore waters in the gas hydrate stability zone from the forearc basin in the eastern Nankai Trough, offshore central Japan, where pore waters are enriched in I and reach ages as old as ∼50 Ma through the sediment column. At the outer ridge site along the trough, on the other hand, relatively younger I are more frequently delivered probably through thrusts/faults associated with subduction. The nature of source formations of I and hydrocarbons in the offshore Shimokita Peninsula has a more terrestrial contribution compared with those in the Nankai Trough, but these formations are also considerably older than the host sediments, suggesting long-term transport of I and hydrocarbons for the accumulation of gas hydrates in both locations. [ABSTRACT FROM AUTHOR]

The title compound is synthesized from a mixture of Al, Al2O3, and Al4C3 in a molar ratio of 3:5:2 (carbon crucible, argon, 2223 K, 1 h). [ABSTRACT FROM AUTHOR]

Background: Sport specialization is associated with increased risk of overuse injuries. However, the effects of sport specialization on the risk of overuse injury may differ by specific sport and sociocultural parameters. This study aimed to determine the associations of sport participation and training volume with previous overuse injuries in Japanese male youth soccer players., Hypothesis: Being highly specialized before the age of 12 years and high training volume relative to participant age would be associated with a history of serious overuse injury., Study Design: Cross-sectional study., Level of Evidence: Level 3., Methods: Survey data were collected from male youth soccer players (seventh-ninth grade) during midseason of the 2020-2021 academic year. Participants completed a questionnaire regarding their status of sport participation (single- and multisport athletes), weekly sports volume in first- sixth grade and injury history in the previous year. Odds ratio (OR) was calculated to identify associations of specialization and training volume with a history of serious overuse injury., Results: A total of 841 players (mean age, 13.7 ± 0.9 years) participated; 11% reported serious overuse injury in the previous year, and 64% participated in other sports before the age of 12 years. Players who participated in other sports at <12 years old (OR, 1.79; 95% CI, 1.09-2.94; P = 0.02) and those who trained for more weekly hours than their age in fifth to sixth grade (OR, 1.70; 95% CI, 1.07-2.72; P = 0.03) had greater odds of reporting serious overuse injuries., Conclusion: Multisport athletes and high training volume in fifth-sixth grade were associated with previous serious overuse injuries., Clinical Relevance: Coaches and parents of male youth soccer players should be aware of the increased risk of serious overuse injury participating in multiple sports simultaneously, and youth athletes should adhere to age-appropriate volume recommendations., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

A new 3D metal-organic framework (MOF), in which 2D layers are interlaced to form a 3D architecture, was synthesized by a reaction of Cu(BF 4 ) 2 and 1,3-bis(4-pyridyl)propane (bpp) in a water/1-hexanol solvent system, and the crystal structure of the MOF was successfully solved. The MOF is reversibly transformed to a 1D chain MOF, which shows gate adsorption properties. The dynamic transformation gives crystal size reduction resulting in a slight change in CO 2 adsorption isotherms. The 1D MOF shows selective adsorption/separation properties on benzene and its analogues with similar sizes and shapes (benzene, toluene, and cyclohexane).

Study Objectives: Sleep breathing patterns are altered by nasal obstruction and respiratory events. This study aimed to describe the relationships between specific sleep oral flow (OF) patterns, nasal airway obstruction, and respiratory events., Methods: Nasal flow and OF were measured simultaneously by polysomnography in 85 adults during sleep. OF was measured 2 cm in front of the lips using a pressure sensor., Results: OF could be classified into three patterns: postrespiratory event OF (postevent OF), during-respiratory event OF (during-event OF), and spontaneous arousal-related OF (SpAr-related OF). Postevent OFs begin at the end of airflow reduction, are preceded by respiratory arousal, and are accompanied by postapneic hyperventilation; during-event OFs occur during nasal flow reduction; and SpAr-related OFs to OF begin during stable breathing, and are preceded by spontaneous arousal but are rarely accompanied by apnea/hypopnea. Multivariate regression showed that nasal obstruction was predictive of SpAr-related OF. The relative frequency of SpAr-related OF events was negatively correlated with the apnea-hypopnea index. The fraction of SpAr-related OF duration relative to total OF duration was significantly greater in patients with nasal obstruction than in those without., Conclusion: SpAr-related OF was associated with nasal obstruction, but not respiratory events. This pattern thus functions as a "nasal obstruction bypass", mainly in normal subjects and patients with mild sleep disordered breathing (SDB). By contrast, the other two types were related to respiratory events and were typical patterns seen in patients with moderate and severe SDB., (© 2015 American Academy of Sleep Medicine.)

The crystal structure of Al3O3.5C0.5 (Z = 3) has been characterized by X-ray powder diffraction (XRPD), transmission electron microscopy, and electron probe microanalysis. The title compound is trigonal with space group R3̅m (centrosymmetric) and hexagonal unit-cell dimensions a = 0.29588(1) nm, c = 2.84080(7) nm, and V = 0.21538(1) nm(3). The initial structural model was determined by the charge-flipping method and subsequently refined by the Rietveld method. The final structural model showed the positional disordering of one of the two types of Al sites. The maximum-entropy method-based pattern fitting (MPF) method was used to confirm the validity of the split-atom model, in which conventional structure bias caused by assuming intensity partitioning was minimized. The reliability indices calculated from the MPF were Rwp = 4.03%, S (= Rwp/Re) = 1.17, Rp = 3.08%, RB = 0.82%, and RF = 0.72%. The crystal was composed of antiphase domains, suggesting the occurrence of the high-low phase transition during the cooling process. The transition would be accompanied by the loss of unit-lattice translation, and hence the disordered structural model determined by XRPD might be of the average structure of the low-temperature phase.

A flexible one-dimensional copper-based coordination polymer (CP) crystal was synthesized and the crystal structure was solved. This CP crystal shows a single step gate adsorption uptake of CO(2) under moderate conditions (268 K ≤ T ≤ 303 K, P < 1 atm) irrespective of no N(2) uptake at 77 K.

The objective of this study is to develop a device for noninvasive local tissue electrical impedance tomography (EIT) using divided electrodes with guard electrodes and to validate its effectiveness using bioequivalent phantoms. For this purpose, we prepared a measurement device and bioequivalent phantoms, measured the electrical characteristics of the phantoms, and validated the method using the phantoms. Monolayer phantoms mimicking the brain and muscle and bilayer phantoms consisting of muscle and brain layers were prepared. The relative differences between the measured electrical conductivities of the monolayer brain and muscle phantoms and the true values determined by the 4-electrode method were both less than 10%. The relative differences between the measured and true values in the bilayer phantoms were less than 20% in both layers. The biological impedance measurement device that we developed was confirmed to be effective for impedance measurement in bilayer phantoms with different electrical impedances. To develop a device for the early diagnosis of breast diseases, the development of a multi-layer phantom and demonstration of the effectiveness of the device for its examination are necessary. If the device that we developed makes impedance measurement in breast tumors possible, it may be used as a new diagnostic modality for breast diseases.