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Due to a high increase in electromagnetic pollution, the protection from non-ionizing electromagnetic radiation (EMR) represents an important problem of contemporary environmental science. We are searching for natural materials with the potential for EMR screening.We have discovered that hydrohalloysite has interesting properties as an EMR absorber. Unfortunately, it is a very unstable material. Drying it for even a short period of time leads to the loss of desired properties. In the paper, we have demonstrated that the intercalation of halloysite (the process of introducing guest molecules into the mineral structure) makes it possible to recover the ability to absorb an electromagnetic wave and obtain a promisingmaterial for electromagnetic field shielding applications. [ABSTRACT FROM AUTHOR]

Herein, we have synthesised and characterised a novel organic–inorganic hybrid crystal, [CH3NH3]2KCr(CN)6 (MACr). Thermal analysis (DSC, TGA-DTA) indicates one structural phase transition (PT) at 450 K. The modified equation of the tolerance factor, t, was used to estimate the theoretical PT temperature for a crystal with Mn(III). According to the X-ray diffraction experiment, in the low-temperature (LT) phase, the solid-to-solid PT is described by the monoclinic space group C2/c. The creation of the ferroelastic domain structure in phase II was proved on the basis of the observation under a polarising microscope. The crystals of MACr and its isomorphous analogues with Fe(III) and Co(III) appeared to be semiconducting materials in the LT phase. The type of PT is order–disorder and occurs between "low" (ordered-frozen) and "high" (orientationally disordered) dielectric states. Dielectric spectroscopy was used to characterise the switching properties of the dipole moments in the vicinity of the PTs. The magnetic properties of the MACr hybrid were investigated in DC and AC modes. The DC data show a sizeable weak exchange interaction between the nearest Cr(III) centres in the crystal lattice. The AC susceptibility data confirm a slow magnetic relaxation in the applied DC field with two relaxation channels. The low-frequency relaxation time is very long as τLF = 1.4(1) s at T = 2.0 K. The organic–inorganic hybrid, described above, can be considered a rare example of multifunctional materials which exhibit dielectric, magnetic, and conductive activities. [ABSTRACT FROM AUTHOR]

We have synthesised and characterised a novel organic–inorganic hybrid crystal, [(CH3)2NH2]2KCr(CN)6. The thermal DSC, TMA, DTG and DTA analyses indicate two solid-to-solid structural phase transitions (PTs). According to the X-ray diffraction experiments, the first PT at 220 K is isostructural, since it does not involve a change of the space group. This transition occurs between the states, where the (CH3)2NH2+ cations are orientationally disordered and ordered (frozen). The other reversible PT at 481 K leads to a melt-like phase similar to the one observed in plastic crystals or polar liquids. Dielectric spectroscopy has been used to characterise the switching properties of the dipole moments in the vicinity of the PTs. Continuous-wave electron paramagnetic resonance spectroscopy was employed to investigate the effect of ordering on the local environment of the Cr3+ ions. We have also applied the quasielastic neutron scattering (QENS) technique as well as 1H NMR spectroscopy to measure the dynamics of the (CH3)2NH2+ cations residing in the inorganic framework. [ABSTRACT FROM AUTHOR]

We have synthesised and characterised a novel organic–inorganic hybrid crystal, [(CH3)2NH2]2KCr(CN)6. The thermal DSC, TMA, DTG and DTA analyses indicate two solid-to-solid structural phase transitions (PTs). According to the X-ray diffraction experiments, the first PT at 220 K is isostructural, since it does not involve a change of the space group. This transition occurs between the states, where the (CH3)2NH2+ cations are orientationally disordered and ordered (frozen). The other reversible PT at 481 K leads to a melt-like phase similar to the one observed in plastic crystals or polar liquids. Dielectric spectroscopy has been used to characterise the switching properties of the dipole moments in the vicinity of the PTs. Continuous-wave electron paramagnetic resonance spectroscopy was employed to investigate the effect of ordering on the local environment of the Cr3+ ions. We have also applied the quasielastic neutron scattering (QENS) technique as well as 1H NMR spectroscopy to measure the dynamics of the (CH3)2NH2+ cations residing in the inorganic framework. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of (1) 2-methylpyrazine (2MP) with 2,5-dichloro-3,6-dihydroxy-p-quinone (chloranilic acid, CLA), (2) 2-methylpyrazine (2MP) with 2,5-dibromo-3,6-dihydroxy-p-quinone (bromanilic acid, BRA), (3) 2,3,5-trimethylpyrazine (TrMP) with 2,5-dichloro-3,6-dihydroxy-p-quinone (chloranilic acid, CLA), and (4) 2,3,5-trimethylpyrazine (TrMP) with 2,5-dibromo-3,6-dihydroxy-p-quinone (bromanilic acid, BRA) were analyzed in terms of the number of independent methyl groups in their crystal structure. The inelastic neutron back-scattering spectra at low temperature (4–40 K) were discussed in terms of methyl group tunnelling. The INS spectra were compared with the temperature dependence of the 1H-NMR spin–lattice relaxation time, particularly at low temperatures, where CH3 tunnelling is postulated. The infrared and Raman spectra at room temperature were recorded for all complexes under investigation. Furthermore, the vibrational spectra were discussed in terms of the structure of molecules and their interactions. The structural phase transition of the TrMP·CLA complex at 171/175 K (cooling/heating) was characterized by DSC and single-crystal X-ray diffraction. Full-geometry optimization was carried out in the solid state in order to obtain the minimum structures and bonding properties. The results are in very good agreement with the experimental data. The infrared spectrum in the harmonic approximation was calculated and a comparative vibrational analysis was performed. CRYSTAL09 vibrational results appear to be in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The crystal structure has been determined for (CH3NH3)2[KCo(CN)6] at temperatures 100 and 443 K. It crystallizes in the monoclinic space group C2/c (LT) and in the cubic one Fm3̅m (HT). The dielectric response has been investigated for single crystals of pure K3[A′(CN)6] and guest–hosts of (CH3NH3)2[KA′(CN)6], where A′ is a trivalent metal, Co or Fe. Their dielectric properties were measured in the frequency range between 135 Hz and 2 MHz in a wide temperature range between 200 and 460 K. The anisotropy of the electric permittivity for single crystals of (CH3NH3)2[KCo(CN)6] was analysed in terms of the crystal structure. The relaxation processes were observed in the case of the pure host K3Fe(CN)6 and the guest/host crystal (CH3NH3)2[KFe(CN)6]. The activation energies of the dielectric relaxation have been estimated to be equal to 44 and 40 kJ mol−1 for (CH3NH3)2[KFe(CN)6] and K3Fe(CN)6, respectively. The mechanism of the phase transitions found at 425 K and 421 K for (CH3NH3)2[KFe(CN)6] and (CH3NH3)2[KCo(CN)6], respectively, has been postulated. From the dielectric losses the value of the electric ac conductivity has been estimated and analyzed in terms of the activation process of the current carriers. [ABSTRACT FROM AUTHOR]

The crystal structure has been determined for (CH3NH3)2[KCo(CN)6] at temperatures 100 and 443 K. It crystallizes in the monoclinic space group C2/c (LT) and in the cubic one Fm3̅m (HT). The dielectric response has been investigated for single crystals of pure K3[A′(CN)6] and guest–hosts of (CH3NH3)2[KA′(CN)6], where A′ is a trivalent metal, Co or Fe. Their dielectric properties were measured in the frequency range between 135 Hz and 2 MHz in a wide temperature range between 200 and 460 K. The anisotropy of the electric permittivity for single crystals of (CH3NH3)2[KCo(CN)6] was analysed in terms of the crystal structure. The relaxation processes were observed in the case of the pure host K3Fe(CN)6 and the guest/host crystal (CH3NH3)2[KFe(CN)6]. The activation energies of the dielectric relaxation have been estimated to be equal to 44 and 40 kJ mol−1 for (CH3NH3)2[KFe(CN)6] and K3Fe(CN)6, respectively. The mechanism of the phase transitions found at 425 K and 421 K for (CH3NH3)2[KFe(CN)6] and (CH3NH3)2[KCo(CN)6], respectively, has been postulated. From the dielectric losses the value of the electric ac conductivity has been estimated and analyzed in terms of the activation process of the current carriers. [ABSTRACT FROM AUTHOR]

This study investigates lead-free organic-inorganic hybrids (C 3 NH 8 ) 2 [BiCl 5 ] ( ABC ) and (C 3 NH 8 ) 2 [BiBr 5 ] ( ABB ), focusing on their structural, dielectric, ferroelectric, and optical properties. Both compounds exhibit paraelectric ( I ) to ferroelectric ( II ) phase transitions (PTs) at 230/233 K and 228/229 K, respectively, transitioning from orthorhombic ( Pnma ) to monoclinic ( P 2 1 ) phases, with distorted [BiX 6 ] 3- octahedra forming 1D chains. Quasielastic neutron scattering and solid-state 1 H NMR studies reveal the localized motion of azetidinium cations. Dielectric measurements of ABC and ABB show step-like permittivity changes by 11-12 units post-transition I → II , demonstrating reversible switching behavior. Absorption studies reveal band gaps of 3.24 eV for ABC and 2.76 eV for ABB , classifying them as insulators. Luminescence spectra at 77K display 578 nm ( ABC ) and 708 nm ( ABB ) emissions, attributed to 3 P 1,0 → 1 S 0 transitions. Both compounds demonstrate stable second harmonic generation (SHG) switching of the on - off type. The switching performance is evaluated over multiple thermal cycles using the t req metric, which decreases with increasing temperature change rate and indicates that ABB 's SHG switching is approximately 30% faster than that of ABC .

The family of Mn-based organic-inorganic hybrids has greatly expanded due to their advantages in applications. They also show superior bright and size-tunable photoluminescence and can be considered a perfect alternative to toxic lead-based compounds. In this work, we present the detailed structural, optical, and electrical characterization of ([(NH 3 CH 2 CH 2 ) 3 NH]) 2 [MnBr 5 ]Br 5 . The title compound exhibits a unique type of inorganic arrangement created by the trigonal bipyramids. It crystallizes in noncentrosymmetric space group R 32, indicating its optical activity, piezoelectricity, and second-order optical nonlinearity proven by the second harmonic of light measurements. The studied crystals exhibit intense photoluminescence originating from the Mn(II) ion 4 T 1 (G) → 6 A 1 transition. The measured lifetime of the photoluminescence emission is ≤1.5 ms, while the measured quantum yield for both powder and crystal samples reaches ∼70%.

Duchenne muscular dystrophy (DMD) is a disease with a life-threatening trajectory resulting from mutations in the dystrophin gene, leading to degeneration of skeletal muscle and fibrosis of cardiac muscle. The overwhelming majority of mutations are multiexonic deletions. We previously established a dystrophic mouse model with deletion of exons 52-54 in Dmd that develops an early-onset cardiac phenotype similar to DMD patients. Here we employed CRISPR-Cas9 delivered intravenously by adeno-associated virus (AAV) vectors to restore functional dystrophin expression via excision or skipping of exon 55. Exon skipping with a solitary guide significantly improved editing outcomes and dystrophin recovery over dual guide excision. Some improvements to genomic and transcript editing levels were observed when the guide dose was enhanced, but dystrophin restoration did not improve considerably. Editing and dystrophin recovery were restricted primarily to cardiac tissue. Remarkably, our exon skipping approach completely prevented onset of the cardiac phenotype in treated mice up to 12 weeks. Thus, our results demonstrate that intravenous delivery of a single-cut CRISPR-Cas9-mediated exon skipping therapy can prevent heart dysfunction in DMD in vivo ., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)

Halobismuthates(III) and haloantimonates(III) with the R 3 MX 6 chemical composition create a new and broadly unexplored class of ferroelectric compounds. In this paper, we report the haloantimonate(III) ferroelectric comprising an aromatic (1,2,4-triazolium) cation, i.e., (C 2 N 3 H 4 ) 3 [SbBr 6 ] ( TBA ). Temperature-resolved structural and spectroscopic studies indicate that TBA undergoes two solid-solid phase transitions between tetragonal [ P 4 2 / m (I)] and monoclinic [ P 2 1 / n (II) and P 2 1 (III)] phases. TBA experiences a paraelectric-ferroelectric phase transition at 271/268 K (II-III) driven by "order-disorder" and "displacive" molecular mechanisms. The ferroelectric properties of phase III have been confirmed by hysteresis loop measurement, and additionally, the acentric order has been further supported by second-harmonic generation measurements. Insight into the molecular origins of the ferroelectric polarization was provided by periodic ab initio calculations using the Berry phase approach at the density functional theory (DFT-D3) method level employed for calculations of spontaneous polarization.

A hydrogen-bonded metallocyanide-based (AZE) 2 (H 3 O)[Co(CN) 6 ] framework was obtained by introducing a hydronium cation to the A 2 B(1)B(2)CN 6 -type structure. Simple K + /H 3 O + substitution exchange the three-dimensional structure of the double-perovskite into two-dimensional layers containing open inorganic cages with a strongly discontinuous improper ferroelastic phase transition.

A new organic-inorganic hybrid, AZEMnBr , has been synthesized and characterized. The thermal differential scanning calorimetry, differential thermal analysis, and thermogravimetric analyses indicate one structural phase transition (PT) at 346 and 349 K, on cooling and heating, respectively. AZEMnBr crystallizes at 365 K in the orthorhombic, Pnma , structure, which transforms to monoclinic P 2 1 / n at 200 K. Due to the X-ray diffraction studies, the anionic MnBr 4 2- moiety is discrete. The azetidinium cations show dynamical disorder in the high-temperature phase. In the proposed structural PT, the mechanism is classified as an order-disorder type. The structural changes affect the dielectric response. In this paper, the multiple switches between low- and high- dielectric states are presented. In addition, it was also observed that the crystal possesses a mutation of fluorescent properties between phase ON and OFF in the PT's point vicinity. We also demonstrate that EPR spectroscopy effectively detects PTs in structurally diverse Mn(II) complexes. AZEMnBr compounds show DC magnetic data consistent with the S = 5/2 spin system with small zero-field splitting, which was confirmed by EPR measurements and slow magnetic relaxation under the moderate DC magnetic field typical for a single-ion magnet behavior. Given the above, this organic-inorganic hybrid can be considered a rare example of multifunctional materials that exhibit dielectric, optical, and magnetic activity.

Tandem duplication mutations are increasingly found to be the direct cause of many rare heritable diseases, accounting for up to 10% of cases. Unfortunately, animal models recapitulating such mutations are scarce, limiting our ability to study them and develop genome editing therapies. Here, we describe the generation of a novel duplication mouse model, harboring a multi-exonic tandem duplication in the Dmd gene which recapitulates a human mutation. Duplication correction of this mouse was achieved by implementing a single-guide RNA (sgRNA) CRISPR/Cas9 approach. This strategy precisely removed a duplication mutation in vivo, restored full-length dystrophin expression, and was accompanied by improvements in both histopathological and clinical phenotypes. We conclude that CRISPR/Cas9 represents a powerful tool to accurately model and treat tandem duplication mutations. Our findings will open new avenues of research for exploring the study and therapeutics of duplication disorders., (© 2021 The Authors. Published under the terms of the CC BY 4.0 license.)

The preparation of materials featuring more than one ferroelectric phase represents a promising strategy for controlling electrical properties arising from spontaneous polarization, since it offers an added advantage of temperature-dependent toggling between two different ferroelectric states. Here, we report on the discovery of a unique ferroelectric-ferroelectric transition in diisopropylammonium tetrabromocadmate ( DPAC , (C 6 H 16 N) 2 [CdBr 4 ]) with a T c value of 244 K, which is continuous in nature. Both phases crystallize in the same polar orthorhombic space group, Iab 2. The temperature-resolved second-harmonic-generation (SHG) measurements using 800 nm femtosecond laser pulses attest to the polar structure of DPAC on either side of the phase transition (PT). The dc conductivity parameters were estimated in both solid phases. The anionic substructure is in the form of [CdBr 4 ] 2- discrete complexes (0D), while in the voids of the structure, the diisopropylammonium cations are embedded. The ferroelectric properties of phases I and II have been confirmed by the reversible pyroelectric effect as well as by P - E loop investigations. On the basis of the dielectric responses, the molecular mechanism of the PT at 244 K has been postulated to be of mixed type with an indication of its displacive nature.

Background: Academic surgeons are encouraged to promote their work on social media. We hypothesized that thoracic surgeons who are active on Twitter have a higher research citation index (Hirsch index [h-index]) than their counterparts who are not., Methods: Thoracic surgeons on CTSNet.org in Canada and the United States were queried for profiles with an h-index on Google Scholar and/or Research Gate in July 2018. Surgeons were categorized by whether they possessed a Twitter account (T+) or not (T-), and h-index values were compared. Within the T+ cohort a multivariate regression model was used to identify independent predictors of increased h-index among variables related to Twitter activity., Results: Of 3741 surgeons queried, 19.3% (722) had a known h-index. The mean h-index for the entire cohort was 14.54 (SD, 15.73). The median h-index was 10 (range, 0-121), and the 75th percentile h-index was 20. T+ surgeons had a median h-index of 10 (range, 0-66), and T- surgeons had a median h-index of 10 (range, 0-72; P = .25). The 75th percentile h-index for T+ surgeons was 23 compared with 20 for T- surgeons (P = .24). For T+ surgeons the regression model identified the number of followers (P = .029), the number of people followed (P = .048), and the frequency of tweeting (P = .046) as independent predictors of a higher h-index., Conclusions: The median h-index for an academic thoracic surgeon in Canada and the United States is 10. Surgeons who engage in Twitter activity are more likely to have their research cited by others., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The single-crystals of mixed (C 3 H 5 N 2 ) 2 [KFe x Co 1-x (CN) 6 ] crystals, with different ratios of x = 0, 0.29, 0.42, 0.51, 0.63, 0.70, 0.85, 1, have been grown from aqueous solutions. The thermal stability of the crystals has been determined using both DTA and TGA analysis. DSC has revealed sequences of structural phase transitions (PTs). We have found four solid phases for the crystals with concentrations x < 0.6 and three phases above these concentrations. The Fe(iii) concentration has been estimated using the SEM technique. We have found the linear relationship of T c versus the molar concentration of Fe(iii) for the IV → III PT. Based on the obtained results, a phase diagram has been constructed. The mechanism of the structural PTs has been discussed based on the results of dielectric relaxation, NIR, IR and Raman spectroscopyand X-ray measurements. Dielectric switching has been observed for all analysed mixed-crystals. All crystals exhibit ferroelastic properties.

The crystals of pure [(CH 3 ) 3 NH] 2 [KFe(CN) 6 ] (TrMAFe) and [(CH 3 ) 3 NH] 2 [KCo(CN) 6 ] (TrMACo) as well as their mixed crystals (TrMAFe x Co 1-x ), with different ratios of x = 0, 0.12, 0.18, 0.49, 0.56, 0.73, 0.81, 1.0, have been grown from aqueous solutions. The structure of TrMACo has been determined at 360 K to be cubic (Fm3[combining macron]m). In phase II (100 K), the TrMACo crystal is monoclinic (C2/c). The thermal stability of the pure and mixed crystals has been determined by using both DTA and TGA. Based on the DSC results, we have found a single phase transition (PT) for both pure and mixed crystals. The Fe(iii) concentration was estimated by using the SEM technique. We have found a linear relationship between the PT temperature (T c ) and the molar concentration of Fe(iii). Based on the obtained results, a phase diagram has been constructed. The mechanism of the structural PT has been discussed based on the results of dielectric relaxation and 1 H NMR and X-ray spectroscopy measurements. The results confirmed that the PT mechanism of both pure and mixed crystals is related to the change in the dynamic state of the TrMA + cations. The dielectric activation energy changes linearly with the mole fraction ranking from 35 to 38 kJ mol -1 , for the mixed crystals.

A description of the thermal, structural, 1H NMR, electric and optical properties of four organic-inorganic hybrids, haloantimonates(iii) and halobismuthates(iii), based on homopiperidinium cation: (C6H14N)2SbCl5 (abbrev. HSC), (C6H14N)2SbBr5 (HSB), (C6H14N)2BiCl6[H3O] (HBC), (C6H14N)2BiBr5 (HBB), is presented. The common feature of the crystal structures of the studied compounds is the 1D (one-dimensional) chain for the anionic network in HSC, HSB and HBB, 1D hydrogen bond chain between 0D (zero-dimensional, isolated) BiCl6 octahedrons and hydronium moieties in HBC as well as a rich polymorphism in the solid state for all title compounds. The structures of the Sb(iii) and Bi(iii) derivatives are not isomorphous and they crystallize in the following space groups: HSC in P212121 both at 280 and 150 K, HSB in Pmna and P212121 at 310 and 150 K, respectively, HBC in C2/m, C2/m and C2/c at 300, 260 and 200 K, respectively, and HBB in P21/n both at 280 and 200 K. The anionic networks are in the forms of either pseudo- and zig-zag chains or a chain of a hydrogen bond. The band gap values, using the Tauc plot as well as the ac and dc conductivity parameters, were estimated. On the basis of the 1H NMR spin-lattice relaxation times, T1, and second-moment, M2, measurements and the dielectric responses, the molecular mechanisms of the phase transitions (PTs) have been postulated. The structural PTs are discussed in terms of the changes in cationic dynamics and distortions of the anionic sublattice. The powder technique of SHG (Kurtz and Perry method) has been used to analyze the second-order nonlinear optical properties of HSC.

Leptin is a peptide hormone that has an essential role in the regulation of body weight by inhibiting food intake and stimulating energy expenditure. The role of leptin in the modulation of the immune response and inflammation has been regarded as important. In rheumatoid arthritis (RA) patients it was reported that fasting leads to an improvement of clinical and biological measures of disease activity, which was associated with a marked decrease in serum leptin. These features suggest that leptin may also influence the inflammatory mechanisms of arthritis in humans. In this study we assessed serum leptin levels in RA and osteoarthritis (OA) patients and found a correlation between serum leptin level and other markers as well as bone mass density changes, activity of disease, disease duration and the age of the patients. The blood was collected from 30 RA and 30 OA patients who constituted the control group. Serum leptin level was determined using the DRG Leptin ELISA Kit-a solid phase enzyme-linked immunosorbent assay based on the sandwich principle. The serum level of leptin in RA patients ranged from 1.8 to 81.1 ng/ml and median value was 11.2. There was a positive correlation between body mass index (BMI) of RA patients and serum level of leptin (correlation coefficients Spearman's r = 0.81). According to correlation coefficients, serum leptin level is independent of age of RA patients, stage of disease, number of painful and swollen joints, duration of morning stiffness, disease duration as well as value of titre of the Waaler-Rose, disease activity score (DAS 28) value and presence of rheumatoid nodules. There was a negative correlation between serum leptin level and glomerular filtration rate (GFR). No correlation between the serum leptin level and T-score was found. An influence of steroid treatment on the serum leptin level was not shown. The median serum leptin level in OA patients was 9.2 ng/ml. There was a positive correlation between body mass index of OA patients and serum level of leptin (correlation coefficients Spearman's r = 0.57). No correlation was found between serum leptin level and patient's age, duration of disease and value of laboratory data. There were no correlations between serum leptin level and visual analogue pain scale (VAS) for the lower-limb afflicted patients as well as stage of disease according to Kellgren and Lawrence's score in OA patients. There was a negative correlation between serum leptin level and T-score value in OA patients (r = -0.58, P < 0.05). No statistically significant differences were found between serum leptin levels for RA and OA patients.