Noncentrosymmetric γ-Cs2I4O11 Obtained from IO4 Polyhedral Rearrangements in the Centrosymmetric ß-Phase.

We report the synthesis and optical properties of noncentrosymmetric (NCS) γ-Cs2I4O11 that was obtained through IO4 polyhedral rearrangements from centrosymmetric (CS) ß-Cs2I4O11. Trifluoroacetic acid (TFA) acts as a structure-directing agent and plays a key role in the synthesis. It is suggested that the function of TFA is to promote rearrangement reactions found in the organic synthesis of stereoisomers. γ-Cs2I4O11 crystallizes in the NCS monoclinic space group P21 (No. 4) and exhibits a strong second-harmonic-generation (SHG) response of 5.0 × KDP (KH2PO4) under 1064 nm laser radiation. Additional SHG experiments indicate that the material is type I phase matchable. First-principles calculations show that SHG intensity mainly comes from its d34, d21, and d23 SHG tensor components. The synthetic strategy of discovering γ-Cs2I4O11 provides a new way for designing novel NCS SHG materials.

Crystal Structures and Property Measurements of Rare Earth Magnesium Thiosilicates Synthesized via Flux Crystal Growth Utilizing the Boron Chalcogen Mixture (BCM) Method.

Nine new rare earth magnesium-containing thiosilicates of the formula RE3Mg0.5SiS7 (Ln = Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er) were synthesized in an alkali halide flux using the boron chalcogen mixture (BCM) method. Crystals of high quality were produced, and their structures were determined by single-crystal X-ray diffraction. The compounds crystallize in the hexagonal crystal system in the P63 space group. Phase pure powders of the compounds were used for magnetic susceptibility measurements and for second-harmonic generation (SHG) measurements. Magnetic measurements indicate that Ce3Mg0.5SiS7, Sm3Mg0.5SiS7, and Dy3Mg0.5SiS7 exhibit paramagnetic behavior with a negative Weiss temperature over the 2-300 K temperature range. SHG measurements of La3Mg0.5SiS7 demonstrated SHG activity with an efficiency of 0.16 times the standard potassium dihydrogen phosphate (KDP).

Enhanced clot lysis by a single point mutation in a reteplase variant.

Recombinant tissue-type plasminogen activator (rtPA) is the clot lysis drug approved for clinical use, and is characterised by a short half-life and substantial inactivation by plasminogen activator inhibitor-1 (PAI-1). We previously discovered that a tPA mutation (A419Y) at the protease domain led to enhanced fibrinolysis activity. In the present study, we studied the mechanism of such mutation in enhancing the proteolytic activity, and whether such enhancement persists in reteplase, an United States Food and Drug Administration-approved tPA truncated variant. We constructed and expressed a series of reteplase-based mutants, including rPAG (glycosylated rPA), rPAG -Y (with A419Y mutant at rPAG ), rPAG -A4 (tetra-alanine mutation at 37-loop of rPAG ), and rPAG -A4/Y (with both) and evaluated their plasminogen activation and PAI-1 resistance. Surface plasmon resonance analysis showed that the rPAG had fibrin affinity comparable to full-length tPA. Moreover, rPAG -Y had 8·5-fold higher plasminogen activation and stronger tolerance to PAI-1 compared to rPAG . We also found that the mutations containing tetra-alanine (rPAG -A4 and rPAG -A4/Y) had dramatically reduced plasminogen activation and impaired clot lysis. In a pulmonary embolism murine model, rPAG -Y displayed a more efficient thrombolytic effect than rPAG . These results identified a novel mutant reteplase variant of tPA with increased fibrinolytic activity, laying the foundation for the development of a new potent fibrinolytic agent.

Ln2 (SeO3 )2 (SO4 )(H2 O)2 (Ln=Sm, Dy, Yb): A Mixed-Ligand Pathway to New Lanthanide(III) Multifunctional Materials Featuring Nonlinear Optical and Magnetic Anisotropy Properties.

Bottom-up assembly of optically nonlinear and magnetically anisotropic lanthanide materials involving precisely placed spin carriers and optimized metal-ligand coordination offers a potential route to developing electronic architectures for coherent radiation generation and spin-based technologies, but the chemical design historically has been extremely hard to achieve. To address this, we developed a worthwhile avenue for creating new noncentrosymmetric chiral Ln3+ materials Ln2 (SeO3 )2 (SO4 )(H2 O)2 (Ln=Sm, Dy, Yb) by mixed-ligand design. The materials exhibit phase-matching nonlinear optical responses, elucidating the feasibility of the heteroanionic strategy. Ln2 (SeO3 )2 (SO4 )(H2 O)2 displays paramagnetic property with strong magnetic anisotropy facilitated by large spin-orbit coupling. This study demonstrates a new chemical pathway for creating previously unknown polar chiral magnets with multiple functionalities.

Common and Distinct Roles of Frontal Midline Theta and Occipital Alpha Oscillations in Coding Temporal Intervals and Spatial Distances.

Judging how far away something is and how long it takes to get there is critical to memory and navigation. Yet, the neural codes for spatial and temporal information remain unclear, particularly the involvement of neural oscillations in maintaining such codes. To address these issues, we designed an immersive virtual reality environment containing teleporters that displace participants to a different location after entry. Upon exiting the teleporters, participants made judgments from two given options regarding either the distance they had traveled (spatial distance condition) or the duration they had spent inside the teleporters (temporal duration condition). We wirelessly recorded scalp EEG while participants navigated in the virtual environment by physically walking on an omnidirectional treadmill and traveling through teleporters. An exploratory analysis revealed significantly higher alpha and beta power for short-distance versus long-distance traversals, whereas the contrast also revealed significantly higher frontal midline delta-theta-alpha power and global beta power increases for short versus long temporal duration teleportation. Analyses of occipital alpha instantaneous frequencies revealed their sensitivity for both spatial distances and temporal durations, suggesting a novel and common mechanism for both spatial and temporal coding. We further examined the resolution of distance and temporal coding by classifying discretized distance bins and 250-msec time bins based on multivariate patterns of 2- to 30-Hz power spectra, finding evidence that oscillations code fine-scale time and distance information. Together, these findings support partially independent coding schemes for spatial and temporal information, suggesting that low-frequency oscillations play important roles in coding both space and time.

Exploring the light-induced dynamics in solvated metallogrid complexes with femtosecond pulses across the electromagnetic spectrum.

Oligonuclear complexes of d4-d7 transition metal ion centers that undergo spin-switching have long been developed for their practical role in molecular electronics. Recently, they also have appeared as promising photochemical reactants demonstrating improved stability. However, the lack of knowledge about their photophysical properties in the solution phase compared to mononuclear complexes is currently hampering their inclusion into advanced light-driven reactions. In the present study, the ultrafast photoinduced dynamics in a solvated [2 × 2] iron(II) metallogrid complex are characterized by combining measurements with transient optical-infrared absorption and x-ray emission spectroscopy on the femtosecond time scale. The analysis is supported by density functional theory calculations. The photocycle can be described in terms of intra-site transitions, where the FeII centers in the low-spin state are independently photoexcited. The Franck-Condon state decays via the formation of a vibrationally hot high-spin (HS) state that displays coherent behavior within a few picoseconds and thermalizes within tens of picoseconds to yield a metastable HS state living for several hundreds of nanoseconds. Systematic comparison with the closely related mononuclear complex [Fe(terpy)2]2+ reveals that nuclearity has a profound impact on the photoinduced dynamics. More generally, this work provides guidelines for expanding the integration of oligonuclear complexes into new photoconversion schemes that may be triggered by ultrafast spin-switching.

Basal transcription profiles of the rhamnose-inducible promoter PLRA3 and the development of efficient PLRA3-based systems for markerless gene deletion and a mutant library in Pichia pastoris.

An ideal inducible promoter presents inducibility with an inducer and no basal transcription without inducer. Previous studies have shown that PLRA3 in Pichia pastoris is a strong rhamnose-inducible promoter for driving the industrial production of recombinant proteins. However, another important profile of PLRA3, the basal transcription, was not investigated yet. In this study, the basal transcription of PLRA3 was assessed according to the profiles of two test strains grown in media lacking rhamnose: (1) the production of secretory ß-galactosidase in P. pastoris GS115/PLRA3-LacB, in which lacB expression was regulated by PLRA3, and (2) growth in P. pastoris GS115/PLRA3-MazF, in which the expression of mazF, which encodes an intracellular toxic protein, was controlled by PLRA3. Analyses revealed low ß-galactosidase production and non-obviously inhibited growth of the test strains, which suggests that there was a low basal transcription level of PLRA3 when rhamnose was absent. Thus, PLRA3 was an excellent candidate for genetic manipulation in P. pastoris due to its strict regulation, a strong and a low transcriptional activity with and without rhamnose, respectively. Subsequently, two systems were developed based on PLRA3 in P. pastoris: (1) an efficient markerless gene deletion system for single or multiple genes and (2) a high efficient piggyBac transposase-mediated mutation system for investigating the functions of unknown genes, as well as for the screening of expected mutants.

BiFSeO3: An Excellent SHG Material Designed by Aliovalent Substitution.

The first bismuth selenite fluoride, BiFSeO3, was obtained by aliovalent substitution of 2D BiOIO3. Its structure features a 3D network composed of 1D [BiF](2+) chains interconnected by SeO3 groups. BiFSeO3 exhibits a very strong second harmonic generation (SHG) effect of about 13.5 times that of KH2PO4 (KDP) under 1064 nm laser radiation and 1.1 times that of KTiOPO4 (KTP) under 2.05 µm laser radiation, which is the highest among all of the metal selenites reported. It has also very simple chemical composition and can be synthesized easily under mild hydrothermal conditions.

Pb4(OH)4(BrO3)3(NO3): An Example of SHG Crystal in Metal Bromates Containing π-Conjugated Planar Triangle.

The first example of SHG crystal in the metal bromates containing π-conjugated planar triangle systems, namely, Pb4(OH)4(BrO3)3(NO3), was successfully synthesized via the hydrothermal method. Furthermore, a single crystal of centrosymmetric Pb8O(OH)6(BrO3)6(NO3)2·H2O was also obtained. Both compounds contain similar [Pb4(OH)4] cubane-like tetranuclear clusters, but they display different one-dimensional (1D) chain structures. Pb4(OH)4(BrO3)3(NO3) features a zigzag [Pb4(OH)4(BrO3)3](+) 1D chain, while Pb8O(OH)6(BrO3)6(NO3)2·H2O is composed of two different orthogonal chains: the linear [Pb4(OH)4(BrO3)2](2+) 1D chain along the b-axis and the zigzag [Pb4O2(OH)2(BrO3)4](2-) 1D chain along the a-axis. The NO3 planar triangles of the compounds are all isolated and located in the spaces of the structures. Pb4(OH)4(BrO3)3(NO3) exhibits the first example of SHG crystal in the metal bromates with π-conjugated planar triangle. The second-harmonic generation (SHG) efficiency of Pb4(OH)4(BrO3)3(NO3) is approximately equal to that of KDP and it is phase-matchable. Dipole moment and theory calculations indicate that BrO3, NO3, and PbO4 groups are the origin of its SHG efficiency, although some of the contributions cancel each other out.

Decompressive Bone Flap Replacement (Decompressive Cranioplasty): A Novel Technique for Intracranial Hypertension-Initial Experience and Outcome.

BACKGROUND: Intracranial hypertension is a life-threatening condition that can be treated by decompressive craniectomy (DC), which involves removing a part of the skull and intracranial lesions. However, DC has many complications and requires a second surgery to repair the skull. Decompressive bone flap replacement (DBFR) or decompressive cranioplasty is a novel technique that replaces the bone flap with a titanium mesh, providing both decompression and skull integrity. METHODS: The materials and methods of DBFR are described in detail. A three-dimensional titanium mesh is fabricated based on the computed tomography (CT) data of previous DC patients. An appropriate titanium mesh is selected based on the preoperative and intraoperative assessments. After removing the intracranial lesions, the titanium mesh is fixed over the bone window. RESULTS: We successfully performed DBFR in three emergent cases. The postoperative CT scan showed adequate decompression in all cases. No reoperation for skull repair was needed, and there were no surgical complications. The cosmetic outcome was excellent. There were no relevant complications in the operative area. CONCLUSIONS: DBFR may be a safe and effective alternative to DC in a specific subgroup of patients, in whom complete removal of the bone flap is feasible. DBFR can reduce intracranial pressure while maintaining the integrity of the skull cavity, eliminating the need for additional surgery for skull repair. Possible improvements for DBFR in the future are suggested, such as using a greater curvature of the titanium mesh or a modified DBFR with a hinged titanium mesh.

Synthesis, Optical, Dielectric, SHG, Magnetic and Visible Light Driven Catalytic Studies on Compounds Belonging to the Swedenborgite Structure.

A new compound, InBaZn3GaO7, with swedenborgite structure along with transition metal (TM) substituted variants have also been prepared. The structure contains layers of tetrahedral ions (Zn2+/Ga3+) connected by octahedrally coordinated In3+ ion forming the three-dimensional structure with voids where the Ba2+ ions occupy. The TM substituted compounds form with new colors. The origin of the color was understood based on the ligand-field transitions. The near IR reflectivity studies indicate that the Ni - substituted compounds exhibit good near - IR reflectivity behavior, making them possible candidates for 'cool pigments'. The temperature dependent dielectric studies indicate that the InBaZn3GaO7 compound undergoes a phase transition at ~360 °C. The compounds are active towards second harmonic generation (SHG). Magnetic studies show the compounds, InBaZn2CoFeO7 and InBaZn2CuFeO7 to be anti-ferromagnetic in nature. The copper containing compounds were found to be good catalysts, under visible light, for the oxidation of aromatic alkenes. The many properties observed in the swedenborgite structure-based compounds suggests that the mineral structure offers a fertile ground to investigate newer compounds and properties.

The human claustrum tracks slow waves during sleep.

Slow waves are a distinguishing feature of non-rapid-eye-movement (NREM) sleep, an evolutionarily conserved process critical for brain function. Non-human studies posit that the claustrum, a small subcortical nucleus, coordinates slow waves. We recorded claustrum neurons in humans during sleep. In contrast to neurons from other brain regions, claustrum neurons increased their activity and tracked slow waves during NREM sleep suggesting that the claustrum plays a role in human sleep architecture.

Noncentrosymmetric Triangular Magnet CaMnTeO6: Strong Quantum Fluctuations and Role of s0 versus s2 Electronic States in Competing Exchange Interactions.

Noncentrosymmetric triangular magnets offer a unique platform for realizing strong quantum fluctuations. However, designing these quantum materials remains an open challenge attributable to a knowledge gap in the tunability of competing exchange interactions at the atomic level. Here, a new noncentrosymmetric triangular S = 3/2 magnet CaMnTeO6 is created based on careful chemical and physical considerations. The model material displays competing magnetic interactions and features nonlinear optical responses with the capability of generating coherent photons. The incommensurate magnetic ground state of CaMnTeO6 with an unusually large spin rotation angle of 127°(1) indicates that the anisotropic interlayer exchange is strong and competing with the isotropic interlayer Heisenberg interaction. The moment of 1.39(1) µB, extracted from low-temperature heat capacity and neutron diffraction measurements, is only 46% of the expected value of the static moment 3 µB. This reduction indicates the presence of strong quantum fluctuations in the half-integer spin S = 3/2 CaMnTeO6 magnet, which is rare. By comparing the spin-polarized band structure, chemical bonding, and physical properties of AMnTeO6 (A = Ca, Sr, Pb), how quantum-chemical interpretation can illuminate insights into the fundamentals of magnetic exchange interactions, providing a powerful tool for modulating spin dynamics with atomically precise control is demonstrated.

Nonadiabatic Charge Transfer within Photoexcited Nickel Porphyrins.

Metalloporphyrins with open d-shell ions can drive biochemical energy cycles. However, their utilization in photoconversion is hampered by rapid deactivation. Mapping the relaxation pathways is essential for elaborating strategies that can favorably alter the charge dynamics through chemical design and photoexcitation conditions. Here, we combine transient optical absorption spectroscopy and transient X-ray emission spectroscopy with femtosecond resolution to probe directly the coupled electronic and spin dynamics within a photoexcited nickel porphyrin in solution. Measurements and calculations reveal that a state with charge-transfer character mediates the formation of the thermalized excited state, thereby advancing the description of the photocycle for this important representative molecule. More generally, establishing that intramolecular charge-transfer steps play a role in the photoinduced dynamics of metalloporphyrins with open d-shell sets a conceptual ground for their development as building blocks capable of boosting nonadiabatic photoconversion in functional architectures through "hot" charge transfer down to the attosecond time scale.

Does the integration of TB medical services in the general hospital improve the quality of TB care? Evidence from a case study in China.

BACKGROUND: Moving the clinical services from tuberculosis (TB) dispensary to the integrated county hospital (called integrated approach) has been practiced in China; however, it is unknown the quality of TB care in the integrated approach and in the dispensary approach. METHODS: A total of 202 new TB patients were investigated using structured questionnaires in three counties implementing the integrated approach and one county implementing the dispensary approach. The quality of TB care is measured based on success rate of treatment, medical expenditure, health system delay and second-line drug use. RESULTS: The integrated approach showed a high success treatment rate. The medical expenditure in the integrated approach was USD 432, significantly lower than that in the dispensary approach (Z = -5.771, P < 0.001). The integrated approach had a shorter health system delay (5 days) than the dispensary approach (32 days). Twenty-six percent of patients in integrated hospitals were prescribed with second-line TB drugs, significantly lower than that in the TB dispensary (47%, χ(2) = 7.452, P = 0.006). However, the medical expenditure, use of second-line anti-TB drug and liver-protection drugs indeed varied greatly across the three integrated hospitals. CONCLUSIONS: The integrated approach showed better quality of TB care, but the performance of the integrated hospitals varied greatly. A method to standardize TB treatment and management of this approach is urgent.

Frontal-midline theta and posterior alpha oscillations index early processing of spatial representations during active navigation.

Previous research has demonstrated that humans combine multiple sources of spatial information such as self-motion and landmark cues while navigating through an environment. However, it is unclear whether this involves comparing multiple representations obtained from different sources during navigation (parallel hypothesis) or building a representation first based on self-motion cues and then combining with landmarks later (serial hypothesis). We tested these two hypotheses (parallel vs serial) in an active navigation task using wireless mobile scalp EEG recordings. Participants walked through an immersive virtual hallway with or without conflicts between self-motion and landmarks (i.e., intersections) and pointed toward the starting position of the hallway. We employed the oscillatory signals recorded during mobile wireless scalp EEG as a means of identifying when participant representations based on self-motion versus landmark cues might have first emerged. We found that path segments, including intersections present early during navigation, were more strongly associated with later pointing error, regardless of when they appeared during encoding. We also found that there was sufficient information contained within the frontal-midline theta and posterior alpha oscillatory signals in the earliest segments of navigation involving intersections to decode condition (i.e., conflicting vs not conflicting). Together, these findings suggest that intersections play a pivotal role in the early development of spatial representations, suggesting that memory representations for the geometry of walked paths likely develop early during navigation, in support of the parallel hypothesis.

Frontal-midline theta and posterior alpha oscillations index early processing of spatial representations during active navigation.

Previous research has demonstrated that humans combine multiple sources of spatial information such as self-motion and landmark cues, while navigating through an environment. However, it is unclear whether this involves comparing multiple representations obtained from different sources during navigation (parallel hypothesis) or building a representation first based on self-motion cues and then combining with landmarks later (serial hypothesis). We tested these two hypotheses (parallel vs. serial) in an active navigation task using wireless mobile scalp EEG recordings. Participants walked through an immersive virtual hallway with or without conflicts between self-motion and landmarks (i.e., intersections) and pointed toward the starting position of the hallway. We employed the oscillatory signals recorded during mobile wireless scalp EEG as means of identifying when participant representations based on self-motion vs. landmark cues might have first emerged. We found that path segments, including intersections present early during navigation, were more strongly associated with later pointing error, regardless of when they appeared during encoding. We also found that there was sufficient information contained within the frontal-midline theta and posterior alpha oscillatory signals in the earliest segments of navigation involving intersections to decode condition (i.e., conflicting vs. not conflicting). Together, these findings suggest that intersections play a pivotal role in the early development of spatial representations, suggesting that memory representations for the geometry of walked paths likely develop early during navigation, in support of the parallel hypothesis.

Polarizable Anionic Sublattices Can Screen Molecular Dipoles in Noncentrosymmetric Inorganic-Organic Hybrids.

We report the growth and photophysical characterization of two polar hybrid lead halide phases, methylenedianiline lead iodide and bromide, (MDA)Pb2I6 and (MDA)Pb2Br6, respectively. The phases crystallize in noncentrosymmetric space group Fdd2, which produces a highly oriented molecular dipole moment that gives rise to second harmonic generation (SHG) upon excitation at 1064 nm. While both compositions are isostructural, the size dependence of the SHG signal suggests that the bromide exhibits a stronger phase-matching response whereas the iodide exhibits a significantly weaker non-phase-matching signal. Similarly, fluorescence from (MDA)Pb2Br6 is observed around 630 nm below 75 K whereas only very weak luminescence from (MDA)Pb2I6 can be seen. We attribute the contrasting optical properties to differences in the character of the halide sublattice and postulate that the increased polarizability of the iodide ions acts to screen the local dipole moment, effectively reducing the local electric field in the crystals.

[The study on Delphi filtering the indicators of evaluation on the diagnosis, treatment and management of MDR-TB].

OBJECTIVE: To filter the indicators of evaluation on the diagnosis, treatment and management of MDR-TB through Delphi. METHODS: Three rounds Delphi was implemented by asking for the 30 experts'score and suggestion of 60 evaluation indicators. The experts were selected from experienced MDR-TB workers. Then the concentration degree (with each indicator's score average and full mark rate to reflect) and coordination degree (with coordination coefficient w to reflect) were analyzed, and the coefficient of variation of each indicator, enthusiasm and authority coefficient Cr etc were calculated. After that, new indicators system was constructed and the experts' were asked for suggestion again. The enthusiasm and coordinate coefficient were used to measure the effect of Delphi. RESULTS: All of the enthusiasm coefficients of experts in three rounds were 100% (30/30), and 40% (12/30), 53% (16/30) and 10% (3/30) of the experts gave suggestions. The degrees of experts' authority in the first 2 rounds were high and the averages were 0.82 and 0.86, respectively. A total of 34 indicators were left after 6 indicators modified and 26 indicators deleted. The 10 indicators were the core indicators, and the average scores of 34 indicators were all higher than 4.7 and the coefficients of variation were less than 0.1, respectively. The coordination coefficients of specialists' opinion were 0.36, 0.25 and 0.68, respectively. CONCLUSION: The final evaluation indicator system include 34 indicators, and the result of the filtering indicators on the diagnosis, treatment and management of MDR-TB through Delphi is good.

Classification of EEG signals: An interpretable approach using functional data analysis.

Electroencephalography (EEG) is a noninvasive method to record electrical activity of the brain. The EEG data is continuous flow of voltages, in this paper, we consider them as functional data, and propose a three-stage algorithm based on functional data analysis, with the advantage of interpretability. Specifically, the time and frequency information are extracted by wavelet transform in the first stage. Then, functional testing is utilized to select EEG channels and frequencies that show significant differences for different human behaviors. In the third stage, we propose to use penalized multiple functional logistic regression to interpretably classify human behaviors. With simulation and a scalp EEG data as validation set, we show that the proposed three-stage algorithm provides an interpretable classification of the scalp EEG signals.