{GdIII7} and {GdIII14} Cluster Formation Based on a Rhodamine 6G Ligand with a Magnetocaloric Effect.

Heptanuclear {GdIII7} (complex 1) and tetradecanuclear {GdIII14} (complex 2) were synthesized using the rhodamine 6G ligand HL (rhodamine 6G salicylaldehyde hydrazone) and characterized. Complex 1 has a rare disc-shaped structure, where the central Gd ion is connected to the six peripheral GdIII ions via CH3O-/µ3-OH- bridges. Complex 2 has an unexpected three-layer double sandwich structure with a rare µ6-O2- ion in the center of the cluster. Magnetic studies revealed that complex 1 exhibits a magnetic entropy change of 17.4 J kg-1 K-1 at 3 K and 5 T. On the other hand, complex 2 shows a higher magnetic entropy change of 22.3 J kg-1 K-1 at 2 K and 5 T.

Chiral Zn3Ln3 Hexanuclear Clusters of an Achiral Flexible Ligand.

Multifunctional single-molecule magnets (SMMs) have sparked great interest, but chiral SMMs obtained via spontaneous resolution are rarely reported. We synthesized a series of chiral trinuclear hepta-coordinate lanthanide complexes [ZnII3LnIII3] (1 for Dy, 2 for Tb, 3 for Gd, and 4 for Dy0.07Y0.93) using the achiral flexible ligand H2L (2,2'-[1,2-ethanediylbis[(ethylimino)methylene]]bis[3,5-dimethylphenol]). The complexes crystallize in the chiral P63 group space, and two enantiomers of different chirality are spontaneously resolved. Three [Zn(L)Cl]- anions utilize the two phenoxy oxygen atoms of each L2- to coordinate with three lanthanide ions, respectively, and the three hepta-coordinate D5h lanthanide ions are arranged in a triangle. The chirality comes from the propeller arrangement of the peripheral three bidentate chelate L2- ligands like octahedral [M(AA)3]n+/- (M = transition metal ions; AA = bidentate chelate ligands, e.g., 2,2'-bipyridine, 1,10-phenathroline, ethylenediamine, acac- or oxalate). Complex 1 exhibits an AC susceptibility signal and is frequency-dependent, which is typical of SMMs. Complex 4, doped with a large amount of diamagnetic Y(III) in Dy(III), exhibits Ueff = 48.3 K and τ0 = 4.4 × 10-8 s in experiments. Complex 2 shows circularly polarized luminescence and apparent photoluminescence, typical of the f-f transitions of Tb(III).

Assembly of a Heterotrimetallic Zn2Dy2Ir Pentanuclear Complex toward Multifunctional Molecular Materials.

Rational selection of metal ions and organic ligands to synthesize metal-organic complexes (MOCs) is necessary for constructing multifunctional materials. Herein, we have obtained a novel heterotrimetallic Zn2Dy2Ir pentanuclear MOC by the assembly of DyIII, luminescent ZnII(valpn), and [IrIII(H2L)(ppy)2]Cl metalloligands (Hppy = 2-phenylpyridine, H2L = 2,2'-bipyridine-5,5'-di-p-benzoic acid). Single-crystal structural analysis shows that the central [IrIII(L)(ppy)2]- bridges two ZnDy moieties using two carboxylates of L2-. Measurements of organic light-emitting diodes (OLEDs) show that the maximum luminance is 284.2 cd/m2 and the turn-on voltage is 6 V. Magnetic studies reveal that Zn2Dy2Ir is a field-induced single-molecule magnet (SMM) with an energy barrier of 19.1(2) K under a 2 kOe dc field. Zn2Dy2Ir shows luminescence sensing with a quenching efficiency of up to 99.0% for 2,4,6-trinitrophenol (TNP).

Magnetooptical Properties of Lanthanide(III) Metal-Organic Frameworks Based on an Iridium(III) Metalloligand.

Integrating magnetic and optical properties into a metal-organic framework (MOF) remains a great challenge. Herein, we have reasonably constructed two 3D magnetooptical MOFs by incorporating a [IrIII(ppy)2(bpy)]+-based fluorescent metalloligand and magnetic LnIII centers. The alternating arrangements of Δ- or Λ-[IrIII(ppy)2(bpy)]+ endow these MOFs with enhanced optical properties. Moreover, the use of DyIII leads to field-induced slow magnetic relaxation. This work provides an effective strategy for the preparation of magnetooptical bifunctional MOFs.

Structural Modulation of Fluorescent Rhodamine-Based Dysprosium(III) Single-Molecule Magnets.

Two rhodamine 6G-based mononuclear dysprosium complexes, [Dy(LR)(LA)2](ClO4)3·Et2O·1.5MeOH·0.5H2O (1) and [Dy(LR)(H2O)4(MeCN)](ClO4)3·2H2O·MeCN (2) (LR = salicylaldehyde rhodamine 6G hydrazone, LA = 2-pyridylcarboxaldehyde benzoyl hydrazone), are synthesized, aiming at improving the magnetic behavior by modulating their coordination environment. Both complexes own one exclusive short Dy-Ophenoxy coordination bond as the predominant bond and exhibit single-molecule magnet behavior under zero dc field with the energy barrier (Ueff/kB) of 90 K (1) and 320 K (2) and apparent hysteresis at 1.9 K. The ab initio calculations indicate that the short Dy-Ophenoxy bond determines the direction of magnetic anisotropic axis for 1 and 2. The quantum tunneling of magnetization (QTM) between the ground Kramers doublets (KDs) in 1 cannot be neglected, leading to an experimental Ueff/kB much lower than the calculated energy of the first excited state (318.2 K). For 2, the stronger magnetic anisotropy and negligible QTM between the ground KDs guarantees that the energy barrier is close to the calculated energy of first KDs (320.8 K). On the other hand, the presence of ring-opened xanthene moiety makes complexes 1 and 2 in the solid state emit red light with emission bands of 645 and 658 nm, respectively.

[Processing mechanism of social cues in faces].

The purpose of the present paper was to review the processing mechanisms of social cues in faces. We summarized researches relative to social cues in faces and discussed the processing mechanism of these cues from the aspects of facial expression, facial attractiveness, gaze and face direction, and lipreading. First, we discussed the general neural mechanism of face information processing and summarized the functions of face areas in the fusiform gyrus, posterior superior temporal sulcus and inferior occipital gyrus. Next, the neural mechanism of emotional face perception was discussed. The processing of emotional faces consists of encodings of perceptual and emotional components. The amygdala plays an important role in the emotional processing of facial expressions. Furthermore, the neural responses to facial expressions may be influenced by multiple factors, such as the type of emotion, the dynamic presentation of the face and the consciousness of facial expressions. With respect to facial attractiveness processing, studies has shown that the reward circuitry is activated by highly attractive faces. However, the influence of facial attractiveness on neural responses remains elusive. It is proposed that the neural responses to facial attractiveness might be modulated by factors such as the task, observer's sex, expectation and other social cues in faces. Eye gaze perception and face view perception are related to visual attention, and the relevant neural circuitry has been found to include attention-related areas, such as the intraparietal sulcus. Finally, research on lipreading reveals its important role in language perception. The auditory cortex and language-related cortex have been shown to be activated by lipreading. In summary, the present evidence may support facial information processing theory. However, the theory could be further improved based on present and future findings. Furthermore, we discussed the deficits in the processing of social cues in individuals with mental disorders and proposed future research directions in this field.

Rhodamine 6G-Labeled Pyridyl Aroylhydrazone Fe(II) Complex Exhibiting Synergetic Spin Crossover and Fluorescence.

Here, we use a pyridinecarbaldehyde rhodamine 6G hydrazone ligand (L) to synthesize an Fe(II) complex 1 for the search of new fluorescent-spin crossover (SCO) materials. Single-crystal structural determinations suggest that the Fe(II) ion is chelated by two ring-opened ligands (L-o) to form a FeN4O2 coordination environment, and intermolecular π---π contacts of the xanthene groups connect the adjacent molecules to form a supramolecular one-dimensional chain. Magnetic susceptibility measurements on complex 1 show that three-step SCO takes place in the temperature range of 120-350 K, and its desolvated form 1-d exhibits SCO around room temperature ( Tc↑ = 343 K and Tc↓ = 303 K) with a wide hysteresis loop of 40 K. Moreover, complex 1-d displays light-induced excited spin-state trapping phenomenon. Intriguingly, the fluorescence intensity of the maximum emission at 560 nm for complex 1-d displays discontinuous variation in the range of 250-400 K, indicative of the occurrence of synergetic fluorescence and SCO.

Rhodamine Salicylaldehyde Hydrazone Dy(III) Complexes: Fluorescence and Magnetism.

Three new dysprosium(III) complexes [Dy2(HL1-o)2(L1)(NO3)3][Dy(NO3)5]·1.5ACE·0.5Et2O (1), [Dy(L1)3]·2.5MeOH·MeCN (2), and [Dy(L2)3]·MeOH·MeCN (3) (HL1 = rhodamine B salicylaldehyde hydrazine, HL2 = rhodamine B 3-methylsalicylaldehyde hydrazine) were synthesized and characterized. Purple complex 1 contains two ring-open ligands HL1-o and shows fluorescence of the rhodamine amide moiety, whereas yellow complexes 2 and 3 are comprised of ring-close ligands (L1/2)- and display fluorescence of the salicylaldehyde Schiff base part. For 2 and 3, Dy(III) ions are nine coordinated by the six oxygen and three nitrogen atoms of three chelate (L1/2)- ligands, but the arrangements of the three ligands are different owing to the methyl substituent on HL2. There are three short predominant Dy-Ophenoxy bonds in 2 and 3. The largest Ophenoxy-Dy-Ophenoxy angle is 148.64(17)° for 2 and 89.63(13)° for 3. Magnetic studies reveal that complex 2 is a field-induced single-molecule magnet ( Ueff = 104.2 K under a dc magnetic field of 2000 Oe), and 3 exhibits only a magnetic relaxation behavior owing to the quantum tunneling of magnetization (QTM). Furthermore, ab initio calculations illustrate that the disposition of predominant Dy-Ophenoxy bonds affects the magnetic anisotropy of the Dy(III) ions and relaxation processes of complexes 2 and 3.

Slow Magnetic Relaxation in a Mononuclear Ruthenium(III) Complex.

The development of magnetic molecules with long spin reversal/decoherence times highly depends on the understanding of relaxation behavior under different external conditions. Herein, a magnetic study on a RuIII complex (1) is presented. Detailed analysis of the relaxation time and the magneto-heat capacity data suggests that the resonant phonon trapping process dominates the magnetic relaxation in the crystalline sample of 1, slowing down the spin relaxation rate, as further confirmed by the measurements on a ground sample and frozen solution. Thus, it provides a rare example showing that 4d metal-centered mononuclear compounds without second-order anisotropy can display slow magnetic relaxation.

Porous Coordination Polymers Based on {Mn6} Single-Molecule Magnets.

In this paper, three isostructural porous coordination polymers, namely, [Mn6(µ3-O)2(sao)6(DMF)4(L(1))2/3]·4DMF·2H2O·2CH3OH (1), [Mn6(µ3-O)2(sao)6(DMF)4(L(2))2/3]·4DMF·2H2O·2CH3OH (2), and [Mn6(µ3-O)2(sao)6(DMF)4(L(3))2/3]·4DMF·4H2O·2CH3OH (3) (DMF = dimethylformamide, H2sao = salicylaldoxime, H3L(1) = benzene-1,3,5-trisbenzoic acid, H3L(2) = 4,4',4″-s-triazine-2,4,6-triyltribenzoic acid, and H3L(3) = 2,4,6-tris(4-carboxyphenoxy)-1,3,5-s-triazine), based on the oximato-bridged {Mn6} single-molecule magnet (SMM) and tricarboxylic acid ligands, were designed and synthesized. X-ray structural analysis shows that they possess a two-dimensional layered structure, where the {Mn6} moieties are linked by the corresponding (L(x))(3-) carboxylate ligands (x = 1, 2, 3) forming a huge honeycomb layer. These compounds not only show the SMM behavior as confirmed by alternative current susceptibility measurements but also show selectivity for CO2 over N2 at 273 K. On the basis of the magnetic fitting to the magnetic susceptibilities and the field dependence of magnetization for complexes 1-3, the spin ground states are S = 4. Compared with isolated {Mn6} SMMs with S = 4, the out-of-phase susceptibilities of 1-3 show obvious peaks only under the external direct-current field of 2 kOe. However, no peaks in χm″ are observed in the partially desolvated sample of compound 1.

Relationships of Blood Pressure Circadian Rhythm and Brain Natriuretic Peptide with Left Ventricular Hypertrophy in the Patients with Primary Hypertension.

Objective To investigate the relationships of blood pressure circadian rhythm and brain natriuretic peptide (BNP) with left ventricular hypertrophy (LVH) in patients with primary hypertension. Methods Totally 349 patients (74 with LVH and 275 without LVH) with primary hypertension were enrolled in this study.Echocardiography was performed to determine left ventricular mass index (LVMI) using the Devereux formula. The nocturnal blood pressure decline rate,24-hour blood pressure (24 h PP; especially 24 h mean systolic blood pressure,24 h SBP) and blood pressure index (PPI) were determined by 24 h-ambulatory blood pressure monitoring. These 349 hypertensive patients were divided into four groups including supper-dipper group (defined as≥;20%, n=7),dipper group (defined as 10%- 20%, n=77),non-dipper group (defined as 0- 10%, n=173),and anti-dipper group (defined as<0, n=92). The baseline demographic characteristics of patients were collected. Fasting blood sugar,blood lipids,blood urea nitrogen,serum cretinine,cystatin C,uric acid,and plasma BNP level were measured. Results The patients with LVH (n=74) had significantly higher percentage of grade 3 hypertension (85.1% vs. 46.9%;χ2=34.428,P<0.001),24 h SBP (134 mmHg vs. 129 mmHg; t=3.175,P=0.002)(1 mmHg=0.133 kPa),daytime-mean SBP (134 mmHg vs. 130 mmHg; t=2.197,P=0.029),night-mean SBP(132 mmHg vs. 121 mmHg; t=4.763,P<0.001),and 24 h PP(57 mmHg vs. 52 mmHg; t=4.120,P<0.001) and PPI (0.43 vs. 0.41; t=3.335,P=0.001) and lower nocturnal blood pressure decline rate [(1.30±8.02)% vs. (5.68±7.25)%; t=-4.510,P<0.001] than the non-LVH patients (n=275). The LVH hypertensive group had significantly higher BNP level (87.8 pg/ml vs. 28.8 pg/ml; t=2.170,P=0.034) and LVMI (135.1 g/m2 vs. 88.7 g/m2; t=15.285,P<0.001) than the control group. No significant difference was observed in the BNP level among supper-dipper,dipper,non-dipper and anti-dipper groups (P=0.137).However,the difference was statistically significant in the LVMI (P=0.001). Additionally,patients in the anti-dipper group had significantly higher LVMI than those in the dipper patients (100.3 g/m2 vs. 86.3 g/m2; t=4.335,P<0.001) and non-dipper (100.3 g/m2 vs.93.7 g/m2; t=1.987,P=0.048). Patients in the non-dipper group had significantly higher LVMI than those in the dipper group (93.7 g/m2 vs. 86.3 g/m2; t=2.693,P=0.008). The multivariate linear correation analysis and logistic regressions analysis suggested a significant correlation of LVMI with BNP and the grade of hypertension. Conclusion With the increasing of plasma BNP level,the left ventricular hypertrophy is closely related to abnormal blood pressure circadian rhythm and the grade of hypertension in primary hypertensive patients.

Slow magnetization relaxation in Ni(II)Dy(III)Fe(III) molecular cycles.

Two cyano- and phenoxo-bridged hexanuclear Ni(II)2Dy(III)2Fe(III)2 (1) and octanuclear Ni(II)4Dy(III)2Fe(III)2 (2) trimetallic cyclic complexes have been obtained. They are the first trimetallic metallocycles. Magnetic studies reveal that 1 and 2 exhibit single-molecule-magnet behavior with an energy barrier of 17.9 K for complex 1 in a 2000 Oe static field and 25.0 K for complex 2 in a zero static field.

Toward higher nuclearity: tetranuclear cobalt(II) metallogrid exhibiting spin crossover.

Supramolecular strategy was employed to achieve the highest nuclearity Co(II) cluster exhibiting spin-crossover (SCO) behavior. Magnetic susceptibility characterization of the Co4(II) complex shows that two different spin-transition processes occur. The SCO behavior is directed by the partially deprotonated polydentate ligand, which favors the structural distortion required by the spin transition.

[Influence factors on the cryosurvival rate of post-thaw spermatozoa from sperm donors].

OBJECTIVE: To investigate the influence of seasons, blood types and semen parameters on the cryosurvival rate of frozen-thawed spermatozoa from sperm donors. METHODS: We retrospectively analyzed the influence of seasons, blood types, abstinence period, semen volume, sperm morphology, and pre-freeze sperm motility and concentration on the cryosurvival rate of frozen-thawed sperm in 4 088 semen samples from Shaanxi Human Sperm Bank. RESULTS: The cryosurvival rate of the post-thaw sperm was correlated negatively with the progressive motility of the pre-freeze sperm (r = -0.262, P < 0.01), but positively with pre-freeze sperm concentration (r = 0.247, P < 0.01), and it was significantly higher in the 6-day abstinence group ([70.2 +/- 5.4]%) than in the other abstinence groups (P < 0.01), so was it in the normal sperm morphology rate > 20% group ([71.4 +/- 5.1]%) than in the others (P < 0.01). The survival rate of the post-thaw sperm was not correlated with seasons, blood types, and semen volume (P > 0.05). CONCLUSION: Sperm motility, concentration and morphology and the abstinence period of sperm donors may be valuable predictors of the cryosurvival rate of post-thaw sperm, but no correlation was found between the survival rate and seasons, blood types and semen volume.

Substituent effects on spin-crossover Fe(II)N4O2 pyrenylhydrazone complexes.

Multifunctional magnetic materials have broad application prospects in molecular switches and information storage. In this study, four mononuclear Fe(II) complexes are synthesized using a series of pyrenylhydrazone ligands HL1-4. Two deprotonated ligands are coordinated to the iron(II) ions in an enolic form, leading to neutral complexes FeII(Lx)2·xsol with a FeIIN4O2 octahedral coordination environment. Magnetic measurements suggest that complex Fe(L1)2·2ACE (1·2ACE, ACE = acetone) is mainly low spin below 300 K and complex Fe(L3)2·ACE (3·ACE) is high spin, whereas complexes Fe(L2)2 (2) and Fe(L4)2·6H2O (4·6H2O) exhibit gradual spin crossover behavior. The spin states of complexes 1-4 are confirmed by single-crystal X-ray diffraction analysis. The substituent effect on the magnetic properties of the complexes is significant in this system. Temperature-dependent fluorescence emission spectra show the coexistence but no coupling effect of spin crossover and fluorescence for complexes 2 and 4·6H2O.

Effect of facial emotion recognition learning transfers across emotions.

Introduction: Perceptual learning of facial expression is shown specific to the train expression, indicating separate encoding of the emotional contents in different expressions. However, little is known about the specificity of emotional recognition training with the visual search paradigm and the sensitivity of learning to near-threshold stimuli. Methods: In the present study, we adopted a visual search paradigm to measure the recognition of facial expressions. In Experiment 1 (Exp1), Experiment 2 (Exp2), and Experiment 3 (Exp3), subjects were trained for 8 days to search for a target expression in an array of faces presented for 950 ms, 350 ms, and 50 ms, respectively. In Experiment 4 (Exp4), we trained subjects to search for a target of a triangle, and tested them with the task of facial expression search. Before and after the training, subjects were tested on the trained and untrained facial expressions which were presented for 950 ms, 650 ms, 350 ms, or 50 ms. Results: The results showed that training led to large improvements in the recognition of facial emotions only if the faces were presented long enough (Exp1: 85.89%; Exp2: 46.05%). Furthermore, the training effect could transfer to the untrained expression. However, when the faces were presented briefly (Exp3), the training effect was small (6.38%). In Exp4, the results indicated that the training effect could not transfer across categories. Discussion: Our findings revealed cross-emotion transfer for facial expression recognition training in a visual search task. In addition, learning hardly affects the recognition of near-threshold expressions.

Optimization of Clostridium beijerinckii semi-solid fermentation of rape straw to produce butyric acid by genome analysis.

Butyric acid is a volatile saturated monocarboxylic acid, which is widely used in the chemical, food, pharmaceutical, energy, and animal feed industries. This study focuses on producing butyric acid from pre-treated rape straw using simultaneous enzymatic hydrolysis semi-solid fermentation (SEHSF). Clostridium beijerinckii BRM001 screened from pit mud of Chinese nongxiangxing baijiu was used. The genome of C. beijerinckii BRM001 was sequenced and annotated. Using rape straw as the sole carbon source, fermentation optimization was carried out based on the genomic analysis of BRM001. The optimized butyric acid yield was as high as 13.86 ± 0.77 g/L, which was 2.1 times higher than that of the initial screening. Furthermore, under optimal conditions, non-sterile SEHSF was carried out, and the yield of butyric acid was 13.42 ± 0.83 g/L in a 2.5-L fermentor. This study provides a new approach for butyric acid production which eliminates the need for detoxification of straw hydrolysate and makes full use of the value of fermentation waste residue without secondary pollution, making the whole process greener and more economical, which has a certain industrial potential.

Integrating spin-dependent emission and dielectric switching in FeII catenated metal-organic frameworks.

Mechanically interlocked molecules (MIMs) including famous catenanes show switchable physical properties and attract continuous research interest due to their potential application in molecular devices. The advantages of using spin crossover (SCO) materials here are enormous, allowing for control through diverse stimuli and highly specific functions, and enabling the transfer of the internal dynamics of MIMs from solution to solid state, leading to macroscopic applications. Herein, we report the efficient self-assembly of catenated metal-organic frameworks (termed catena-MOFs) induced by stacking interactions, through the combination of rationally selected flexible and conjugated naphthalene diimide-based bis-pyridyl ligand (BPND), [MI(CN)2]- (M = Ag or Au) and Fe2+ in a one-step strategy. The obtained bimetallic Hofmann-type SCO-MOFs [FeII(BPND){Ag(CN)2}2]·3CHCl3 (1Ag) and [FeII(BPND{Au(CN)2}2]·2CHCl3·2H2O (1Au) possess a unique three-dimensional (3D) catena-MOF constructed from the polycatenation of two-dimensional (2D) layers with hxl topology. Both complexes undergo thermal- and light-induced SCO. Significantly, abnormal increases in the maximum emission intensity and dielectric constant can be detected simultaneously with the switching of spin states. This research opens up SCO-actuated bistable MIMs that afford dual functionality of coupled fluorescence emission and dielectricity.

Spin transitions in Fe(II) metallogrids modulated by substituents, counteranions, and solvents.

Two bis(tridentate) Schiff base ligands H2L(x) were used to construct three 2×2 grid-type tetranuclear Fe(II) complexes 1-3 to obtain polynuclear spin-crossover materials. Magnetic susceptibility measurements show that the spin states of the complexes are related to the substituents of H2L(x), and that spin transition occurs only in complexes 1 and 2, which are derived from a bulky ligand, whereas complex 3 is diamagnetic. The transition temperatures of complexes 1 and 2 are close to room temperature and are dependent on counteranions. The spin transition of complex 1 can be reversibly tuned by the dehydration and hydration process.

Emotional Recognition Training Enhances Attention to Emotional Stimuli Among Male Juvenile Delinquents.

Objective: Juvenile delinquents have deficits in emotional recognition that might play a critical role in the development of aggression. The present study aimed to investigate the effect of emotional recognition training and its consequences on emotional attention and aggression. Methods: Seventy-three male juvenile delinquents were randomly assigned to two groups. One group was the modification group, which received eight days of training on an emotional recognition task. The purpose of the training was to modify interpretative biases in emotion recognition to encourage the perception of happiness over anger in ambiguous expressions. The other group was the waitlist group, which did not perform a task and continued with their usual programme. Before and after the training, participants completed the aggression questionnaire (AQ) and two behavioural tasks, including the emotional recognition task and a visual search task with happy and angry faces as targets. Results: The modification group recognized more faces as happy after emotional recognition training than the waitlist group. Furthermore, the hostility in the modification group decreased significantly. Importantly, emotional recognition training further affected attention to emotional faces as participants responded faster in searching for happy and angry faces after training. Conclusion: Emotional recognition training could modify juvenile delinquents' emotional recognition, enhance their visual attention to emotional faces and reduce hostility.