Tuning the polarity of charge carriers in N-heterocyclic carbene-based single-molecule junctions via atomic manipulation.

Tuning the polarity of charge carriers at a single-molecular level is essential for designing complementary logic circuits in the field of molecular electronics. Herein, the transport properties of N-heterocyclic carbene (NHC)-linked single-molecule junctions are investigated using the ab initio quantum transport approach. The results reveal that the hydrogen atoms in NHCs function as a switch for regulating the polarity of charge carriers. Dehydrogenation changes the chemical nature of NHC anchors, thereby rendering holes as the major charge carriers rather than electrons. Essentially, dehydrogenation changes the anchoring group from electron-rich to electron-deficient. The electrons transferred to molecules from the electrodes raise the molecular level closer to the Fermi level, thus resulting in charge carrier polarity conversion. This conversion is influenced by the position and number of hydrogen atoms in the NHC anchors. To efficiently and decisively alter charge carrier polarity via atomic manipulation, a methyl substitution approach is developed and verified. These results confirm that atomic manipulation is a significant method for modulating the polarity of charge carriers in NHC-based single-molecule devices.

Silver electrodes provide higher conductance than gold for thiol-terminated oligosilane molecular junctions: the interfacial effect.

The understanding of the interfacial effect on charge transport is essential in single-molecule electronics. In this study, we elucidated the transport properties of molecular junctions comprising thiol-terminated oligosilane with three to eight Si atoms and two types of Ag/Au electrode materials employing different interfacial configurations. First-principles quantum transport calculations demonstrated that the interfacial configuration determines the relative magnitude of the current between the Ag and Au electrodes, wherein the Ag monoatomic contact configuration presented a larger current than did the Au double-atom configuration. Further, the mechanism of electron tunneling from the interfacial states through the central σ channel was revealed. In contrast to Au double-atom electrodes, Ag monoatomic electrodes exhibit a higher current due to the presence of Ag-S interfacial states closer to the Fermi level. Our findings show that the interfacial configuration is a plausible way to generate the relative magnitude of current of thiol-terminated oligosilane molecular junctions with Au/Ag electrodes and provide further insight into the interfacial effect on the transport properties.

First-principles studies on the electronic and photocatalytic water splitting properties of surface functionalized Y2C-based MXenes.

Recently, MXenes, an emerging family of two-dimensional (2D) materials, have attracted increasing interest for photocatalytic water splitting due to their various excellent physical and chemical properties, such as large specific surface area, good hydrophilicity, and remarkable light absorption ability. However, the photocatalysts of MXenes with symmetric structures are limited by rapid recombination of photo-generated carriers and the prerequisite of a large band gap no less than 1.23 eV. Differently, Janus MXenes with different surface functional groups facilitate the separation of photo-generated electrons and holes with the help of the intrinsic electric field. And, at the same time, there is no prerequisite for the band gap of Janus MXene photocatalysts as long as they possess appropriate band edge positions. Here, we explored the structural, electronic and photocatalytic water splitting properties of symmetric Y2CT2 and Janus Y2CTT' MXenes (T, T' = H, F, Cl, OH) using the density functional theory (DFT) method. Our calculations show that all the investigated Y2CT2 are not suitable photocatalysts for photocatalytic water splitting at all pH values (pH = 0, 7, and 14). In contrast, all the investigated Janus Y2CTT' MXenes are good water splitting photocatalysts with high optical absorption coefficients and remarkable solar-to-hydrogen (STH) efficiencies larger than 18% at pH = 14. Moreover, the STH efficiencies are larger than 18% even at all investigated pH values for Y2CHCl (18.5-22.6%), Y2 CFCl (∼18.7%), and Y2 C(OH)Cl (∼19.4%). Based on the first-principles calculations, we here for the first time propose an easy strategy to design Janus MXene photocatalyst candidates with possible high STH efficiency according to the electronic properties of their symmetric counterparts. Our study is helpful for the future design of Janus MXenes and more generally Janus 2D photocatalysts for water splitting with high STH efficiency.

Mechanically controllable conductance in carbon nanotube based nanowires.

Carbon nanotubes (CNTs) are considered to be promising candidates for fabricating nanowires, due to their stable quasi-one-dimensional structure. Controlling the electronic transport properties is one of the most vital issues for molecular nanowires. Herein, using density functional theory combined with nonequilibrium Green's function method, we systematically investigate the current evolution of (4, 4) single-walled CNT based nanowires in squashing processes. When the CNTs are squashed by applying different pressure along the radial direction, a negative correlation can be found between the electrical conductance of the nanowire and the pressure. Besides, the response of the nano junction current to pressure is influenced by the squashing direction. Not only does the geometric structure show symmetry breaking in the specific squashing direction, which causes the CNT electrodes to change from conductors to semiconductors, but also obvious π stacking behavior can be witnessed in this squashing direction. More intriguingly, because the current of the nano junction can be completely cut off by squashing the CNTs, a significant switching behavior with the on/off ratio of up to 103 is obtained at low bias voltages. The underlying mechanisms for these phenomena are revealed by the analysis of the band structures, transmission spectra, frontier molecular orbitals and transmission pathways. These electronic transport properties make CNT a promising candidate for realizing conductance controllable nano devices.

Interfacial electronic properties between PtSe2 and 2D metal electrodes: a first-principles simulation.

Monolayer (ML) PtSe2 is a two-dimensional (2D) semiconductor with a modest band gap and high carrier mobility, and it is a promising 2D material for electronic devices. Finding suitable metal electrodes is a key factor in fabricating high-performance PtSe2 field effect transistors (FETs). In this study, a series of 2D metals, transition metal dichalcogenides (NbSe2, TaS2), borophene, and MXenes (V2C(OH)2, V2CF2, Nb2C(OH)2, Nb2CF2, Nb2CO2, Hf2C(OH)2, Hf2CF2) were used as electrodes for FET fabrication. The interfacial electronic properties of electrodes and PtSe2 were studied in both the vertical and lateral directions using the ab initio method. In the vertical direction, PtSe2 formed ohmic contacts with most of the 2D metals except for Nb2CF2 and Hf2CF2. Specifically, in the cases of Nb2CF2 and Hf2CF2, p- and n-type Schottky contacts were formed with Schottky barrier heights (SBHs) of 0.48 eV and 0.02 eV, respectively. In the lateral direction, PtSe2 with contacting Hf2CF2 and V2C(OH)2 electrodes formed n-type Schottky contacts with SBHs of 0.14 eV and 0.09 eV, respectively. In the cases of TaS2 and Nb2CF2 electrodes, p-type Schottky contacts with SBHs of 0.35 eV and 0.29 eV, respectively, were formed. Moreover, n-type ohmic contacts were observed when Hf2C(OH)2 and Nb2C(OH)2 electrodes were applied, and p-type ohmic contacts were formed when borophene, NbSe2, Nb2CO2, and V2CF2 electrodes were used. This work reports a systematic investigation of ML PtSe2-2D metal interfaces and serves as a practical guide for selecting electrode materials for PtSe2 FETs.

Regulating the electronic properties of the WGe2N4 monolayer by adsorption of 4d transition metal atoms towards spintronic devices.

We study the regulation of the electronic and spin transport properties of the WGe2N4 monolayer by adsorbing 4d transition metal atoms (Y-Cd) using density functional theory combined with non-equilibrium Green's function. It is found that the adsorption of transition metal atoms (except Pd, Ag and Cd atoms) can introduce a magnetic moment into the WGe2N4 monolayer. Among the transition metal atoms, the adsorption of Nb and Rh atoms transforms WGe2N4 from a semiconductor to a half-metal and a highly spin-polarized semiconductor, respectively. The half-metallic Nb-adsorbed WGe2N4 system is selected to investigate the spin transport properties, and a high magnetoresistance ratio of 107% is achieved. In both parallel and antiparallel magnetization configurations, the spin filtering efficiency reaches close to 100% in the whole bias range, and the antiparallel magnetization configuration exhibits a dual spin filtering effect with a rectification ratio of up to 104. Our study predicts that the adsorption of 4d transition metal heteroatoms is an effective method to regulate the electronic and magnetic properties of WGe2N4 towards high-performance spintronic devices.

[Cross-sectional analysis of libido status and risk factors in male patients with chronic headache].

OBJECTIVE: Exploring the libido status of male chronic headache patients and analyzing its relationship with headache symptoms, sleep, anxiety, and depression, providing reference for the comprehensive treatment of male chronic headache. METHODS: 179 patients with chronic headache who visited the Third Affiliated Hospital of Qiqihar Medical College from January 2022 to February 2023 were selected. The male Self Rated Libido Scale , Visual Analog Scale for Pain, Migraine Disability Assessment Scale, Pittsburgh Sleep Quality Index, Generalized Anxiety Disorder Scale-7, and Patient Health Questionnaire-9 were used to evaluate the libido status, headache severity, disability level, sleep quality, anxiety, and depression of the research subjects, respectively. RESULTS: Among 179 male chronic headache patients, 97 were chronic migraine (CM) patients and 82 were chronic tension type (CTT) patients, and 47 were screened for low libido. The influencing factors of libido in male chronic headache patients include age, smoking, frequency of exercise, course of disease, severity of pain, frequency of headache, disability score, sleep quality, anxiety and depression (all P<0.05). Compared with male CTT patients, male CM patients have higher pain severity, headache frequency, disability score, and anxiety score, while lower libido score (all P<0.05). The results of multivariate analysis showed that age, frequency of exercise, course of disease, severity of pain, frequency of headache, degree of disability, sleep quality, anxiety, and depression were the influencing factors for the decline of libido in male chronic headache patients. CONCLUSION: It is common for male chronic headache patients to experience decreased libido, with male chronic migraine (CM) patients exhibiting more severe reductions. Advanced age, decreased physical activity, longer disease duration, severe pain intensity, frequent headaches, higher disability levels, poor sleep, anxiety, and depression are risk factors for decreased libido in male chronic headache patients.

Design of multifunctional spin logic gates based on manganese porphyrin molecules connected to graphene electrodes.

The spin-resolved transport properties of molecular logic devices composed of two Mn porphyrin molecules connected to each other via a six-carbon atomic chain were studied using the non-equilibrium Green's function combined with density functional theory. The molecules were symmetrically connected to armchair graphene nanoribbon electrodes through four-carbon atomic chains on the left- and right-hand sides. Our calculations revealed that the spin-resolved current-voltage curves depend on the initial spin setting of the transition metal Mn atoms and carbon atoms on the zigzag edges where the electrodes come in contact with the molecule. By simultaneously regulating the spin orientations of the intermediate functional molecules and the zigzag edges of the armchair graphene nanoribbon electrodes, seven spin polarization configurations were obtained. These configurations were examined in this study considering the spin-related symmetry of molecular junctions. By meticulously selecting different combinations according to the specific input and output signals, YES, NOT, OR, NOR, and XOR multifarious spin logic devices were created. The findings of this study are expected to contribute toward the extension of molecular junction functions in future spintronic integrated circuit design and further miniaturization.

Schottky diodes based on blue phosphorene nanoribbon homojunctions.

Diodes have been widely studied as one of the most commonly used electronic components in circuits, and it is important to find diodes with an excellent rectification performance. Herein, we investigate the electronic and transport properties of Schottky contact diodes based on zigzag hydrogenated blue phosphorene nanoribbons, by employing density functional theory combined with the non-equilibrium Green's function. It is found that the adsorption of transition metal atoms Sc/Cr/Ti and Ni on the top site of blue phosphorene nanoribbons leads to metallic and semiconducting properties, respectively. Devices consisting of the planar contact of the metallic and semiconducting nanoribbons show rectifying behavior due to the Schottky barriers of the homojunctions. The current is preferential to flow from the semiconducting side to the metallic side. The rectification ratio of the Sc-Ni device and the Cr-Ni device can reach up to 108, which is much higher than that of traditional p-n junctions of about 105-107. The high rectification ratio at low bias regions, together with the low threshold voltages and negligible reverse currents, make blue phosphorene nanoribbon homojunctions ideal rectifier diodes.

[Study on regulation of CYP450 enzyme system to reduce liver toxicity through compatibility of Aconiti Kusnezoffii Radix Cocta with Chebulae Fructus and Glycyrrhizae Radix et Rhizoma].

Aconiti Kusnezoffii Radix Cocta is one of the most commonly used medicinal materials in Mongolian medicine. Due to the strong toxicity of Aconiti Kusnezoffii Radix Cocta, Mongolian medicine often uses Chebulae Fructus, Glycyrrhizae Radix et Rhizoma to reduce the toxicity, so as to ensure the curative effect of Aconiti Kusnezoffii Radix Cocta while ensuring its clinical curative effect, but the mechanism is not clear. The aim of this study was to investigate the effects of Chebulae Fructus, Glycyrrhizae Radix et Rhizoma and Aconiti Kusnezoffii Radix Cocta on the mRNA transcription and protein translation of cytochrome P450(CYP450) in the liver of normal rats. Male SD rats were randomly divided into negative control(NC) group, phenobarbital(PB) group(0.08 g·kg~(-1)·d~(-1)), Chebulae Fructus group(0.254 2 g·kg~(-1)·d~(-1)), Glycyrrhizae Radix et Rhizoma group(0.254 2 g·kg~(-1)·d~(-1)), Aconiti Kusnezoffii Radix Cocta group(0.254 2 g·kg~(-1)·d~(-1))and compatibility group(0.254 2 g·kg~(-1)·d~(-1),taking Aconiti Kusnezoffii Radix Cocta as the standard). After continuous administration for 8 days, the activities of total bile acid(TBA), alkaline phosphatase(ALP), amino-transferase(ALT) and aspartate aminotransferase(AST)in serum were detected, the pathological changes of liver tissue were observed, and the mRNA and protein expression levels of CYP1 A2, CYP2 C11 and CYP3 A1 were observed. Compared with the NC group, the serum ALP, ALT and AST activities in the Aconiti Kusnezoffii Radix Cocta group were significantly increased, and the ALP, ALT and AST activities were decreased after compatibility. At the same time, compatibility could reduce the liver injury caused by Aconiti Kusnezoffii Radix Cocta. The results showed that Aconiti Kusnezoffii Radix Cocta could inhibit the expression of CYP1 A2, CYP2 C11 and CYP3 A1, and could up-regulate the expression of CYP1 A2, CYP2 C11 and CYP3 A1 when combined with Chebulae Fructus and Glycyrrhizae Radix et Rhizoma. The level of translation was consistent with that of transcription. The compatibility of Chebulae Fructus and Glycyrrhizae Radix et Rhizoma with Aconiti Kusnezoffii Radix Cocta could up-regulate the expression of CYP450 enzyme, reduce the accumulation time of aconitine in vivo, and play a role in reducing toxicity, and this effect may start from gene transcription.

A first-principles study of phthalocyanine-based multifunctional spintronic molecular devices.

In this study, using the first-principles method, we theoretically investigated the spin-dependent transport properties of a phthalocyanine (Pc) molecule, which is sandwiched between two zigzag-edged graphene nanoribbon (zGNR) electrodes. Owing to the spatial symmetry of the Pc molecule and spin splitting of zGNRs around Fermi energy, perfect spin filtering behavior is observed in designed molecular junctions. Meanwhile, the spin of electrons allowed through the device is right opposite to the spin polarization of zGNR electrodes. Further studies show that the spin filtering performance can be largely modulated by insetting different transition metal atoms (TM = Mn or Cr) into the central Pc molecule, and changing the spin-polarized direction of the TM atom leads to the spin filtering direction inversion. More intriguingly, the antiparallel magnetic configuration of two zGNR electrodes gives rise to the control of the conducting channel by bias polarization, which eventually leads to remarkable spin rectifying and giant magnetoresistance behaviors in transition metal phthalocyanine (TMPc) molecular junctions. The corresponding mechanisms are revealed by an analysis of spin-resolved transmission spectra, molecular projected self-consistent Hamiltonian and a projected density of states. These results are helpful in the design of TMPc-based multifunctional spin molecular devices.

Carry-On Nitric-Oxide Luggage for Enhanced Chemotherapeutic Efficacy.

In this work, we proposed a carry-on nitric-oxide (NO) luggage strategy for enhanced chemotherapeutic efficacy. A stimuli-responsive NO-releasing polypeptide was prepared as the building block to assemble into a micelle as a chemodrug-carrier. The micelle was anchored with cRGD peptide with the aim of targeting to tumors' neoangiogenesis. In situ generation of NO at the tumor site can promote the neovascularization to recruit more chemotherapeutics. Besides, the introduced exogenous NO can directly induce apoptosis, synergistically with the chemotherapeutics. A specific near-infrared-region (NIR) NO-probe was also developed to be coloaded to the micelle to report the in situ NO-release. In vitro and in vivo experiments were performed to demonstrate the targeting capability, increased accumulation, real-time NO-release reporting phenomenon, improved antitumor efficacy, and favorable biosafety. Embedding NO into drug cargo as carry-on luggage for enhanced chemotherapeutic efficacy, hopefully, can cast new lights and build a basic principle in the future clinical translation of nanomedicines.

Pervasive Ohmic contacts of monolayer 4-hT2 graphdiyne transistors.

Monolayer (ML) graphdiyne, a two-dimensional semiconductor with appropriate band gap and high carrier mobility, is a promising candidate for channel material in field effect transistors (FETs). Using density functional theory combined with non-equilibrium Green's function method, we systematically investigate the contact and transport properties of graphdiyne FETs with various electrodes, including metals (Cu, Au, Ni, Al and Ag) and MXenes (Cr2C, Ta2C and V2C). Strong interaction can be found between ML graphdiyne and the Cu, Ni and MXenes electrodes with indistinguishable band structure of ML graphdiyne, while weak or medium interaction exists in the contacts of ML graphdiyne and the Au, Al and Ag electrodes where the band structure of ML graphdiyne remains intact. Despite the different contact interactions, Ohmic contacts are generated with all considered electrode materials owing to the weak Fermi level pinning of graphdiyne. The linear I-V characteristic curve verifies the Ohmic contact between Au electrode and graphdiyne ultimately. The theoretically calculated Schottky barrier heights of graphdiyne with Cu electrode are consistent with the available experimental data. Our calculation suggests that graphdiyne is an excellent channel material of FETs forming desired Ohmic contacts with wide-ranging electrodes and thus is promising to fabricate high performance FETs.

Anisotropic interfacial properties of monolayer C2N field effect transistors.

Monolayer C2N is promising for next-generation electronic and optoelectronic applications due to its appropriate band gap and high carrier efficiency. However, relative studies have been held back due to the lack of high-quality electrode contacts. Here, we comprehensively study the electronic and transport properties of monolayer C2N with a series of electrode materials (Al, Ti, Ni, Cu, Ag, Pt, V2C, Cr2C and graphene) by using the nonequilibrium Green's function (NEGF) method combined with density functional theory (DFT). The monolayer C2N forms Ohmic contacts with the Ti/Cu/Ag electrode material in both armchair and zigzag directions, whereas Ohmic contact is only formed in the zigzag direction of the C2N-Al field effect transistor. However, the C2N-Ni, -Pt, -V2C, -Mo2C, -graphene contact systems form n-type Schottky contacts in either the armchair or zigzag direction owing to the relatively strong Fermi level pinning (the pinning factor S = 0.32 in the armchair direction and S = 0.26 in the zigzag direction). By insertion of BN or graphene between the C2N and Pt electrode in the armchair direction of contact systems, the Fermi level pinning can be effectively weakened due to the suppression of metal-induced gap states. Conspicuously, an Ohmic contact is realized in the C2N field effect transistors with the BN-Pt electrode, suggesting a possible approach to fabricating high-performance devices. Our study is conducive to selecting appropriate electrode materials for C2N-based field effect transistors.

[Research development on modern pharmacological effect of tetrandrine].

Han stephania, also known as Stephania tetrandra, expelling wind, relieve pain and inducing diuresis for removing edema, is a traditional Chinese medicine for treating rheumatic arthralgia. Alkaloids have an important pharmacodynamic basis in S. tetrandra, and tetrandrine is one kind content of bisbenzylisoquinoline alkaloids, which has many biological activities. These activities include anti-tumor in many ways, clinically inhibiting multiple inflammatory factors, preventing and treating liver fibrosis and renal fibrosis and many other kinds of fibrotic diseases, and in addition, tetrandrine could work synergistically with other drugs. In recent years, through in-depth research by scholars at home and abroad, it has been found that tetrandrine has a protective effect on the nervous system and ischemia-reperfusion injury. At the same time, as a calcium ion antagonist, tetrandrine could effectively block the deposition of calcium ions inside and outside the cell. In summary, the application prospect of tetrandrine in clinical practice is very extensive. In this paper, the pharmacological effects of tetrandrine and the possible mechanisms for these effects are summarized, and review its current research progress. It is hoped that the possible application direction of tetrandrine can be revealed more comprehensively, and provide better enlightenment and ideas for clinical application.

Surface engineering of phosphorene nanoribbons by transition metal heteroatoms for spintronics.

Modulating the electronic and magnetic properties of phosphorene is important for fabricating multi-functional electronic and spintronic devices. Employing density functional theory combined with the non-equilibrium Green's function, we systematically investigate the electronic, magnetic and transport properties of hydrogenated armchair phosphorene nanoribbons chemically modified by 3d transition metal atoms (Sc, Ti, V, Cr, Mn, Fe, Co and Ni). With chemical adsorption of transition metal atoms, the phosphorene nanoribbons exhibit excellent spin-polarized transport properties. A giant magnetoresistance effect is found with Ti, Fe and Mn adsorption, in which ratios higher than 102 for the Ti and Mn cases, and 105 for the Fe case, are exhibited. Moreover, in the bias range of (-0.2 V, 0.2 V), the Ti, V, Mn and Fe-adsorbed nanoribbons with parallel spin configurations demonstrate a remarkable bias-independent spin filtering efficiency at about 100%, while the Fe and Mn-adsorbed nanoribbons with antiparallel spin configuration show a dual spin filtering effect. The spin-polarized electronic transport properties are closely related to the band structures. Remarkable spin-polarization of the current occurs when the dispersed and flat bands near the Fermi level originate from different spin orientations. The magnetic moments of transition metal adatoms on nanoribbons are reduced by 0.2-2 µB relative to the isolated atoms due to electron rearrangement and charge transfer, which results in various degrees of spin polarization. These results provide a fundamental understanding of the electronic, magnetic and transport properties of transition metal modified hydrogenated armchair phosphorene nanoribbons, and suggest a referential approach to manufacture spintronic devices based on phosphorene.

[Analysis on mechanism of toxicity reduction through compatibility of Aconiti Lateralis Radix Praeparata-Glycyrrhizae Radix et Rhizoma from in vitro component changes,in vivo metabolism and biological effects antagonism].

Aconiti Lateralis Radix Praeparata and Glycyrrhizae Radix et Rhizoma is a representative acid-alkali drug pair,commonly used in clinical application of traditional Chinese medicine( TCM). Its unique compatibility connotation fully embodied the wisdom of ancient people in drug use. In order to more comprehensively and deeply understand the scientific connotation of the compatibility of the two drugs,pharmacy workers have studied the mechanism of reducing toxicity and enhancing efficacy through their compatibility from the perspectives of chemistry,pharmacology and toxicology. On the basis of combing the previous research work,this paper interpreted the unique compatibility connotation from the three-level system of reducing the content of toxic components in vitro by hydrolysis,lipid exchange and formation of associations,the active constituents of Glycyrrhizae Radix et Rhizoma affecting the metabolism of toxic components and direct antagonism of the toxic effects of aconite in vivo. The existing problems and controversies of the modern mechanism of their compatibility were also proposed,providing a reference for further in-depth studies.

Effect of childhood trauma on cognitive functions in a sample of Chinese patients with schizophrenia.

In this study, we aimed to determine the influence of various types of childhood trauma (CT) on cognitive functions in Chinese patients presented with schizophrenia. One hundred sixty-two patients were assessed with the Childhood Trauma Questionnaire-Short Form (CTQ-SF) and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). We investigated the correlations between various types of CT, demographic characteristics, and cognitive functions. Significant negative correlations were observed in physical abuse (PA) and sexual abuse (SA) with the language score (r=-0.190, -0.216, respectively, p<0.05). Similarly, physical neglect (PN) and the total score of CTQ were negatively correlated with the attention score (r=-0.17, -0.206, p<0.05, respectively) as well as the total RBANS score (r=-0.199, -0.223, respectively P<0.05). PN was also negatively correlated with delayed memory (r=-0.167, p<0.05). Regressions analysis indicated significant negative correlations between PN and attention, as well as the cognitive total score (p<0.001). Furthermore, demographic variables (years of education, family income) and clinical characteristics (type of anti-psychotics, duration of illness and times of recurrence) were correlated with cognitive functions. The current study showed that different types of CT could impact specific cognitive functions in Chinese schizophrenia patients. Therefore, we recommend that trauma-focused mental interventions for schizophrenia patients should be developed and routinely offered to patients.

Bone marrow stromal cells transplantation combined with ultrashortwave therapy promotes functional recovery on spinal cord injury in rats.

OBJECTIVE: This study investigated the effects of bone marrow stromal cells (BMSCs) transplantation combined with low dose ultrashortwave (USW) radiation on functional recovery from spinal cord injury (SCI) in rats. Female Sprague-Dawley rats (n = 64) were randomly divided into five groups: sham-operated, as well as control, USW, BMSCs, and BMSCs + USW that were subjected to spinal cord contusion. BMSCs were transplanted into rats in the BMSCs and BMSCs+USW groups, while those in the USW and BMSCs + USW were exposed to radiation; Basso-Beattie-Bresnahan (BBB) tests were performed before the operation and at 1-week intervals after SCI for 7 weeks. 7 weeks later, animals were assessed footprint pattern, motor evoked potential (MEP), histological features, and expression of the ED1 and glial fibrillary acidic protein (GFAP), markers of activated macrophages and astrocytes, respectively, in the lesion area. BBB scores were higher in the BMSCs + USW than in the BMSCs and control groups. The USW and BMSCs + USW groups had improved coordination compared to the BMSCs and control groups (P < 0.01 and P < 0.001, respectively, vs. control). BMSCs + USW rats had a lower ratio of lesion/cavity to spinal cord area than the other injured rats, and also had expression of GFAP in transplanted BMSCs. All treatment groups had lower ED1 expression and MEP latency than the controls (P < 0.01 and P < 0.001, respectively). The results indicate that BMSCs transplantation combined with USW radiation is more effective than either treatment alone in promoting functional recovery after SCI, possibly due to concomitant suppression of inflammation and spinal cord repair.

The effect of Duschinsky rotation on charge transport properties of molecular junctions in the sequential tunneling regime.

We present here a systematic theoretical study on the effect of Duschinsky rotation on charge transport properties of molecular junctions in the sequential tunneling regime. In the simulations we assume that only two electronic charging states each coupled to a two dimensional vibrational potential energy surface (PES) are involved in the transport process. The Duschinsky rotation effect is accounted by varying the rotational angle between the two sets of displaced PESs. Both harmonic potential and anharmonic Morse potential have been considered for the cases of the intermediate to strong electron-vibration couplings. Our calculations show that the inclusion of the Duschinsky rotation effect can significantly change the charge transport properties of a molecular junction. Such an effect makes the otherwise symmetric Coulomb diamond become asymmetric in harmonic potentials. Depending on the angle of the rotation, the low bias current could be significantly suppressed or enhanced. This effect is particularly prominent in the Franck-Condon (FC) blockade regime where the electron-vibration coupling is strong. These changes are caused by the variation of the FC factors which are closely related to the rotational angle between the two sets of PESs involved in the charge transport process. For a molecular junction with Morse potentials, the changes caused by Duschinsky rotation are much more complicated. Both the amplitude and shape of the Coulomb diamond are closely dependent on the rotational angle in the whole range from 0 to 2π. One interesting result is that with a rotation angle of π (and also π/2 for certain cases) symmetric Coulomb diamonds can even be formed from the intrinsically asymmetric Morse potential. These results could be important for the interpretation of experimental observations.