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The low sensitivity of liquid‐state nuclear magnetic resonance (NMR) can be overcome by hyperpolarizing nuclear spins by dissolution dynamic nuclear polarization (dDNP). It consists of transferring the near‐unity polarization of unpaired electron spins of stable radicals to the nuclear spins of interest at liquid helium temperatures, below 2 K, before melting the sample in view of hyperpolarized liquid‐state magnetic resonance experiments. Reaching such a temperature is challenging and requires complex instrumentation, which impedes the deployment of dDNP. Here, we propose organic conductive polymers such as polyaniline (PANI) as a new class of polarizing matrices and report 1H polarizations of up to 5 %. We also show that 13C spins of a host solution impregnated in porous conductive polymers can be hyperpolarized by relayed DNP. Such conductive polymers can be synthesized as chiral and display current induced spin selectivity leading to electron spin hyperpolarization close to unity without the need for low temperatures nor high magnetic fields. Our results show the feasibility of solid‐state DNP in conductive polymers that are known to exhibit chirality‐induced spin selectivity. [ABSTRACT FROM AUTHOR]

The metal‐organic framework (MOF) derived Ni–Co–C–N composite alloys (NiCCZ) were "embedded" inside the carbon cloth (CC) strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion application. The NiCCZ was then oxygen functionalized, facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization, generating a flower‐like metal hydroxysulfide structure (NiCCZOS) with strong partial implantation inside CC. Thus obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three‐electrode configuration. Moreover, when paired with the biomass‐derived nitrogen‐rich activated carbon, the asymmetric supercapacitor device shows almost 100% capacity retention even after 45,000 charge–discharge cycles with remarkable energy density (59.4 Wh kg–1/263.8 µWh cm–2) owing to a uniquely designed cathode. Furthermore, the same electrode performed as an excellent bifunctional water‐splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction (OER) and 168.4 mV for hydrogen evolution reaction (HER) at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and OER. Hence, a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

The formation of dimer [(μ-Cl)Rh-(κ3(P,Si,Si)PhP(o-C6H4CH2SiiPr2)(o-C6H4CH2SiiPrnPr))]2 (Rh-3) with an n-propyl group on one of the silicon atoms as a minor product was affected by the reaction of [RhCl(COD)]2 with proligand PhP(o-C6H4CH2SiHiPr2)2, L1. The major product of the reaction was monomeric 14-electron Rh(III) complex [ClRh(κ3(P,Si,Si)PhP(o-C6H4CH2SiiPr2)2)] (Rh-1). Computations revealed that the monomer–dimer equilibrium is shifted toward the monomer with four isopropyl substituents on the two Si atoms of the ligand as in Rh-1; conversely, the dimer is favored with only one n-propyl as in Rh-3, and with less bulky alkyl substituents such as in [ClRh(κ3(P,Si,Si)PhP(o-C6H4CH2SiMe2)2]2 (Rh-2). Computations on the mechanism of formation of Rh-3 directly from [RhCl(COD)]2 are in agreement with the experimental findings and it is found to be less energetic than if stemming from Rh-1. Additionally, a Si–O–Si complex, [μ-Cl-Rh{κ3(P,Si,C)PPh(o-C6H4CH2SiiPrO SiiPr2CH-o-C6H4)}]2, Rh-4, is generated from the reaction of Rh-1 with adventitious water as a result of intramolecular C–H activation. [ABSTRACT FROM AUTHOR]

The MOF material NU-1000 was employed to host Ni tripodal complexes prepared from new organometallic precursors [HNi(κ4(E,P,P,P)-E(o-C6H4CH2PPh2)3], E = Si (Ni-1), Ge (Ni-2). The new heterogeneous catalytic materials, Ni-1@NU-1000 and Ni-2@NU-1000, show the advantages of both homogeneous and heterogeneous catalysts. They catalyze the hydroboration of aldehydes and ketones more efficiently than the homogeneous Ni-1 and Ni-2, under aerobic conditions and show recyclability. [ABSTRACT FROM AUTHOR]

Tooth loss can lead to occlusal disorders and temporomandibular joint issues, resulting in pain and deteriorating chewing ability. Oral health problems affect health-related quality of life, especially anxiety, distress, and shame. However, the number of studies describing these effects in Vietnam is still limited. To describe clinical, subclinical characteristics and some related factors in patients with tooth extraction. A descriptive cross-sectional study was conducted on 200 patients aged 18 years and older with tooth extraction at Can Tho University of Medicine and Pharmacy Hospital. The information about age, sex, education, place of residence, the reasons for tooth extraction, clinical and subclinical characteristics, and the number of extracted teeth was recorded. Data were analyzed using SPSS 20's Frequency test, Chi-Square test, and Fisher's Exact test. Out of 256 teeth extracted, in which the main reason was misaligned teeth (38.28%), followed by decayed teeth (25.39%) and retained roots (12.89%). Tooth extraction was more common in women (63.32%) than men (36.68%). People who brushed their teeth less than twice a day, and did not have dental visits in the past 12 months accounted for the highest proportion (92.5%, 58.5%). There was also a statistically significant difference between urban (71.43%) and rural (28.57%) patients. Low education level was the reason for the prevalence of oral diseases, while higher education level played a preventive role (p=0.046<0.05). In the elderly group, the proportion of patients with tooth extraction due to oral disease increased (p=0.002<0.05). On average, a patient had less than two teeth extracted. Tooth decay and misaligned teeth were the most common causes of extraction. It was reported that some socio-economic factors are associated with tooth extraction. [ABSTRACT FROM AUTHOR]