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Self-oscillating magnetometers with high sensitivity are widely used in fields such as biomedicine and remote sensing. However, few studies comprehensively consider the effect of different parameters on their performance. We examined the effects of laser intensity, resonance detuning, radio frequency (RF) magnetic field, and atomic cell on the performance of portable self-oscillating magnetometers. To obtain the atomic absorption spectrum, we solved the system’s master equation in the multipole moment form. In theory, we analyse the influencing factors on the atomic magnetic resonance (AMR) signal. In the experiment, we artificially varied the relevant parameters to control the trends of changes in the atomic absorption spectra and evaluated their performance. The results are beneficial for optimizing the parameters of portable self-oscillating magnetometers with a laser pump-probe structure.

Multidimensional Floquet-driven alignment systems with dynamical symmetry present various exotic phenomena and applications. However, there are challenges in directly characterizing large-spin dynamical symmetry from spectra. Here, we first observe the symmetry-protected selection rules of dynamical high-dimensional parity in a large-spin (F= 4) system. We theoretically construct a Floquet-driven alignment system that can be used to reveal high-dimensional spatiotemporal symmetry. In the experiment, the system is implemented in Cs atomic gas subjected to two-dimensional Floquet-modulated magnetic resonance driving. By developing Floquet detection protocols of alignment double-sided spectra, we directly verify symmetry-protected selection rules of dynamical high-dimensional parity for large-spin systems. This work advances the exploration of dynamical symmetry to large spins, and unravels a universal Floquet scheme for the investigation of symmetry-protected selection rules.

We present a theoretical study of double-resonance alignment magnetometers using linearly polarized light, in which the effect of atomic high-order multipole moments is considered. Starting from the effective master equation of our system obtained by eliminating the excited state adiabatically, we derive the full evolution equations of the atomic multipole moments. The analytic solutions of resonance signals involving the four-order multipole moments effect are obtained by using the perturbation approach. We present that the four-order multipole moments effect is negligible in the weak laser field, and the results reduce to that obtained by a three-step approach. However, the role of four-order multipole moments coupled by two-order tensor moments is more significant with the increasing Rabi frequency of light, which cannot be ignored. Meanwhile, the analytic expressions of relaxation processes are also studied, which are a linear combination of the laser-induced equivalent relaxation rate Γ_L and the spin-exchange collision rate Γ_g. The expected domain of validity of the three-step approach on light power is roughly given by Γ_L<12Γ_g. In addition, the steady-state results of resonance signals are presented in a strong radio-frequency magnetic field; in that case, the physical mechanism of the splitting of resonance signals is discussed. These results are valid for arbitrary light power and for an arbitrarily oriented static magnetic field.

The mechanisms underlying the lineage switching from prostate adenocarcinoma (AdPC) to lethal neuroendocrine prostate cancer (NEPC) have yet to be completely elucidated. In this study, RNA sequencing data from a unique patient-derived xenograft NEPC model and a clinical NEPC cohort were used to identify the potential genes driving NEPC progression. Enrichr analysis resulted in the identification of SRY-related HMG-box gene 2 (SOX2) as a potential repressor that causes decrease in the expression of AdPC specific genes in NEPC. Assays involving the stable overexpression of SOX2 in LNCaP and CWR22RV1 cells validated this role of SOX2 in vitro. Mechanistic studies showed that the repressor role of SOX2 was attributed to the marked global hypomethylation of histone H3, which was driven by the activation of lysine-specific demethylase 1 (LSD1). Furthermore, Enrichr also predicted SOX2 as a driver gene involved in the upregulation of NEPC specific genes. However, SOX2 alone could only marginally induce the expression of some neuroendocrine markers in vitro, which was consistent with previous reports. Moreover, we also elucidated the molecular features of LNCaP-SOX2 cells that may confer resistance to androgen-deprivation therapy (ADT) and the inclination toward neuroendocrine transdifferentiation. The results of this study reveal a novel mechanism for SOX2 in the progression of NEPC via LSD1-mediated global epigenetic modulation. This discovery suggests that LSD1 may be a selective target for the prevention of NEPC progression.

The mechanisms underlying the lineage switching from prostate adenocarcinoma (AdPC) to lethal neuroendocrine prostate cancer (NEPC) have yet to be completely elucidated. In this study, RNA sequencing data from a unique patient-derived xenograft NEPC model and a clinical NEPC cohort were used to identify the potential genes driving NEPC progression. Enrichr analysis resulted in the identification of SRY-related HMG-box gene 2 (SOX2) as a potential repressor that causes decrease in the expression of AdPC specific genes in NEPC. Assays involving the stable overexpression of SOX2 in LNCaP and CWR22RV1 cells validated this role of SOX2 in vitro. Mechanistic studies showed that the repressor role of SOX2 was attributed to the marked global hypomethylation of histone H3, which was driven by the activation of lysine-specific demethylase 1 (LSD1). Furthermore, Enrichr also predicted SOX2 as a driver gene involved in the upregulation of NEPC specific genes. However, SOX2 alone could only marginally induce the expression of some neuroendocrine markers in vitro, which was consistent with previous reports. Moreover, we also elucidated the molecular features of LNCaP-SOX2 cells that may confer resistance to androgen-deprivation therapy (ADT) and the inclination toward neuroendocrine transdifferentiation. The results of this study reveal a novel mechanism for SOX2 in the progression of NEPC via LSD1-mediated global epigenetic modulation. This discovery suggests that LSD1 may be a selective target for the prevention of NEPC progression.

Negative linear compressibility (NLC) is a common sense violation (that is, crystal phases expand in one or more directions under hydrostatic compression). The excellent NLC performance of crystal materials is intrinsically related to the geometric structure of its skeleton. Here, we discovered a crystalline porous organic salt (CPOS-1); high-pressure X-ray diffraction experiments reveal that the CPOS-1 shows colossal NLC (Kc= −90.7 T Pa–1) behavior along the caxis. This incredible performance arises from the flexible “supramolecular spring” formed by the charge-enhanced N–H+···–O–S hydrogen bond interaction between the anionic sulfonate and the cationic ammonium ion. Furthermore, we reveal the relationship between this rare NLC behavior and single crystal proton conductivity using high-pressure electrochemical impedance spectroscopy (EIS) method. We believe that NLC behavior research on such inexpensive and readily available porous organic materials is of great significance for accelerating the research and application of NLC materials, especially in organic system.

We demonstrate a simple technique to lock the frequency of a laser to an atomic transition with a new technique of subnatural linewidth spectroscopy. The coupled rubidium system exhibits an enhanced absorption spectrum of the probe beam with a subnatural linewidth. Compared with other techniques with an additional laser, our scheme only utilizes a single laser, which will be locked. The observed spectroscopic linewidth is down to about 3.5 MHz. The laser frequency fluctuation is about 226 kHz after locking on. The demonstrated scheme offers a convenient and low-cost technique for laser frequency stabilization and related precision measurements.

Remote-controlled nanomaterials, used to regulate rapid conversion of light energy into internal energy, are an emerging technology for achieving real-time control of enzymatic and catalytic industrial processes. One means of achieving control is through alteration of the photothermal ability of plasmonic nanostructures to deliver internal energy to enzymes in order to regulate catalytic rates. Such smart systems design is applicable to fields of enzymology, biological engineering, and chemical synthesis. Here, we fabricate enzyme-conjugated gold nanorod composites (EGCs) viaself-assembly to enhance enzymatic activity, reusability, and thermal stability of mesophilic, thermophilic, and hyperthermophilic enzymes. Using the photothermal effect of EGCs to convert near-infrared (NIR) laser irradiation to internal energy, rapid elevation of local temperature and enzyme activity and real-time control over the reaction are achieved. We also demonstrate that enzymes with higher optimal temperatures are especially suitable for use in the remote-controlled nanobiocatalytic system. Ultimately, the photothermal effect of EGCs exhibits excellent promiscuity, catalytic efficiency (8-fold higher), and yield (99%) and achieves aldol addition within 30 min. Thus, EGCs possess great potential benefits for industrial applications and can be incorporated into real-time enzyme catalysis systems that are regulated using remote-controlled nanobiocatalytic strategies.

Based on the assumption of plane section, ideal elastic-plastic model of steel and the constitutive relations of concrete in Chinese Code for Design of Concrete Structures, numerical method is used to analyze the relationship of the axial force-moment-curvature on RC section. After dividing the normal section into strips, we adopt the secant stiffness iteration method (according to the results of each iteration, modify the secant stiffness through changing the elastic modulus of materials) to compile computer program. The results of the paper show a good agreement with those of the analytical method. Comparing with the analytical method, the numerical method of the paper can be wildly used in the application.

In order to analyze the factors those influence the intelligence utilization of college students serving in rural areas and to provide appropriate recommendations. By investigating the needs of college students in Wuhan Province through questionnaire and personal interviews, the results show that college-graduates play a pivotal role in the construction of rural culture and economy in China, but they would like to concern their own interests such as the wage, the geographical choice and the like. Government should start with some objective factors when they employ college students to rural areas, especially to the less developed regions in western .The policy also should combine with the actual situation and emphasize on the specific characteristics to enhance the attractiveness.

In the treatment of methyl orange simulation printing and dyeing wastewater by catalytic wet air oxidation method, the Ru series catalysts were prepared with the equal amount impregnation method. The catalyst activity and stability were characterized by the decolorization rate of the water samples, and the eluted metal ion concentration from the catalyst of the water samples. XRD, SEM, FT-IR were used to characterize the catalysts. The results showed that: when active allocation ratio of the catalyst was Ru:Cu:Fe:Ce:La = 1:0.5:0.5:0.5:0.5, the degradation rate of methyl orange could reach up to 98.5%. And the concentration of each metal component eluted lower after the reaction, while its activity and stability were relatively high.The active component of 1wt% Ru catalyst mainly existed as the form of γ-Al2O3, RuO2, La2O3, La2CuO4 and CeO2. The surface of catalyst was relatively flat and flaky. The Ru catalyst appeared strong infrared absorption in the vicinity of 1070 cm-1, 1650 cm-1 and 3450 cm-1.

It mainly focuses on the research of the occurred problems and the suggested solutions when the dimension of the injection part die is calculated. The algorithm we usually use in enterprises is mid-value difference method, but it often appears parts working dimensions out of tolerance; So a compensatory algorithm based on mid-value difference method was developed, and the compensation algorithm and modified formula used in the thickness direction are put forward for sheet part. A series of sheet part are analyzed by ANSYS thermal transient analysis module, and the parameters in the compensation algorithm in the thickness direction are determined. The compensation results show that parts working dimensions in the thickness direction is in tolerance.

Objective To assess risk factors of acute kidney injury in congenital cardiac disease following cardiac surgery with cardiopulmonary bypass in children. Methods A 50% postoperative creatinine increase was regarded as the criterion of acute kidney injury. 124 children aged 3 years or little undergoing cardiac surgery were divided into three groups: (1) negative AKI (-); (2) AKI (+) with an increase in postoperative creatinine from 150% to 200%; and (3) AKI (++) with an increase in postoperative creatinine by more than 200%. Demographics, and preoperative, intraoperative, and postoperative variables were evaluated for associations with AKI using univariate and multiple logistic regression analysis. Results Several variables, including mortality, preoperative albumin and creatinine levels, cardiopulmonary bypass duration, and postoperative creatinine levels, were significant differences among the three groups (P < 0.05). Multiple regression analysis demonstrated that three risk factors, age (OR, 0.962; 95% CI, 0.925 to 1.000; P = 0.046), intraoperative red blood cell transfusion (OR, 1.003; 95% CI, 1.001 to 1.005; P = 0.030), and cardiopulmonary bypass duration (OR, 1.024; 95% CI, 1.016 to 1.032; P = 0.000) were independently associated with AKI after cardiac surgery. Conclusions This study showed that younger age, incremental intraoperative red blood cell transfusion, and prolonged cardiopulmonary bypass duration were independently associated with acute kidney injury after cardiac surgery. The type of congenital cardiac disease should be included in the analysis of acute kidney injury.

The Whole-cell patch clamp technique was used to study the properties of voltage dependent ion channel expressed by the cultured types A、B、C neurosecretory cells dissociated from medulla terminalis X-organ (MTXO) of Chinese mitten crab Eriocheir sinensis 24-48 hours after plating. Under voltage clamp conditions, significantly inward currents were recorded from all three kinds of neurons, followed by large outward currents. When outward currents were suppressed with use of 3mmol/L 4-aminopyridine (4-AP) and 30mmol/L tetraethylammonium (TEA), a tetrodotoxin-sensitive Na+ current （INa） and a slow (time to peak current 6~8mS at +10mV), Cd2+-sensitive Ca2+ current (ICa) were resolved. INa was activated at potential-40mV and was maximal at-10mV. In TTX, ICa was activated at potential-30mV, was maximal at 10~20mV. In the presence of 1mol/L TTX and 0.5mmol/L Cd2+, a 4-AP-sensitive transient current and a slower-rising, TEA-sensitive current were recorded from a holding potential of-50mV. On the basis of electric feature and pharmacology, transient current was identified as IA, and late, slower-rising current as IK. IA and IK showed the same activation threshold of-30mV. In conclusion, no differences were observed on the properties and kinetics of ionic current among the three kinds of neurons. By comparison with those described in crab Cardisoma carnifex and crayfish Procambarus clarkia, there existed diversity of excitability in X-organ peptidergic neurons from different crustaceans.

Hirudin is the most potent natural inhibitor of thrombin and a powerful anticoagulant. Large-scale production of recombinant hirudin is desirable for therapy. In this study, the gene encoding hirudin variant III was redesigned and synthesized by using Bacillus subtilis preferred codons, and the recombinant hirudin variant III (rHV3) was overexpressed in B. subtilis DB403 with strong anticoagulation activity for the first time. The hirudin activity from the supernatant of culture with optimized expression conditions could reach 210 ATU/ml. The protein in culture supernatant was precipitated by trichloroacetic acid, then desalted by ultrafiltration and purified by anion exchange chromatography. Strong anion Q F.F. performed better than weak anion DEAE F.F. The proper pH and conductivity was determined at pH 8 and 6 ms/cm, respectively. The maximum applied sample was 240 ATU/ml to medium of strong anion Q F.F. This optimized procedure was employed in strong anion exchange HiPrep 16/10Q with the 90% recovery rate and 70.2% purity. After gel filtration, the purity of rHV3 checked by HPLC could reach 95.1%, and the recovery rate was 93% for this step. The purified recombinant rHV3 showed a single band in SDS-PAGE. The rHV3 was stable at 100 oC and acidity condition, but was unstable under the condition of both heating and alkalinity. In conclusion, theses studies suggests that B.subtilis might be useful for the production of biologically active medicine peptides in secretion facilitating purification procedures, and that this isolation method was suitable for scale-up purification process at a low cost.

The feasibility of constructing a tissue-engineered heart valve on an acellular porcine aortic valve leaflet was evaluated. A detergent and enzymatic extraction process was developed to remove the cellular components from porcine aortic valves. The acellular valve leaflets were seeded for 7 days in vitro with cells from canine arterial wall and endothelial cells. The constructs were implanted into the lumens of 6 canine abdominal aortas to assess the reconstruction of the valve leaflets. It was found that all cellular components had been removed from the porcine aortic valves. The valve leaflets were completely reconstructed at the end of the 10th week in vivo. Scanning electron microscopy showed that the valve leaflets were partially covered with endothelial cells. It was concluded that porcine aortic valves can be decellularized by the detergent and enzymatic extraction process and it is feasible to construct a tissue-engineered heart valve in vivo on an acellular valve scaffold.

Two acrylic monomers bearing a pyrimidinyl moiety, N-acryloyl-N'-2-pyrimidinylpiperazine (APMP) and N-methacryloyl-N'-2-pyrimidinylpiperazine (MPMP), are prepared by reactions of N-2-pyrimidinylpiperazine with corresponding acryloyl chlorides in the presence of triethylamine. APMP and MPMP can be polymerized either by using radical initiators such as azobisisobutylonitrile or potassium persulfate (KPS) or by UV light irradiation without any sensitizer. APMP, MPMP, and their polymers are water soluble and liposoluble. They can act as sensitizers to initiate the photopolymerizations of acrylonitrile (AN) in DMF and acrylamide (AAm) or N-acryloylmorpholine (AMPL) in an aqueous medium. They can also act as one component of a redox initiation system by combining with KPS to initiate the polymerization of AAm in an aqueous medium, and a superhigh molecular weight up to 10⁶–10⁷ for P(AAm) or 10⁵–10⁶ for P(AMPL) is obtained. The above polymerizations are pursued kinetically. The mechanism of the photopolymerizations initiated by MPMP or P(MPMP) are confirmed by an electron spin resonance study. By the fluorescent analysis of PAN and P(AAm) initiated by MPMP, APMP, or their polymers we confirm that they not only initiate the polymerization but also enter the polymer chains. The fluorescence spectra of MPMP, APMP, and their polymers are recorded. A fluorescence structural self-quenching effect is also observed. The fluorescence of P(MPMP) can be quenched by adding electron-deficient unsaturated compounds such as methacrylonitrile, AN, fumaronitrile, tetracyanoethylene, methyl acrylate, and methyl methacrylate and the correlation between the Stern–Volmer constants and the electron deficiency of the quenchers is described. The fluorescence quenching of P(MPMP) by a water-soluble C60 derivative is also demonstrated. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 19–28, 2000

Four acrylic monomers bearing phenothiazine oxide moieties, that is, N-acryloyl-phenothiazine-5-oxide (APTO), N-acryloyl-2-chlorophenothiazine-5-oxide (ACPTO), N-acryloyl-phenothiazine-5,5-dioxide (APTDO), and N-acryloyl-2-chlorophenothiazine-5,5-dioxide (ACPTDO) were synthesized by oxidation of corresponding N-acryloyl-phenothiazine (APT) and N-acryloyl-2-chlorophenothiazine (ACPT) using sodium perborate as an oxidant. These monomers could easily be polymerized by initiation of AIBN. The emission fluorescence spectra of the monomers and their polymers were recorded, and the results indicated that these 4 new monomers possess a fluorescence structural self-quenching effect (SSQE), as we have reported previously. Moreover, with the change of the electronic structure of sulfur atom in the phenothiazine chromophore, that is, from sulfide to sulfoxide and sulfone groups, the tendency of SSQE of these monomers is in the order of APT > APTO > APTDO. This would be ascribed mainly to the decrease of electron-donating abilities of monomers in a sequence of sulfide, sulfoxide, and sulfone groups; that is, at the sulfur atom of these monomers, APT has 2 lone-pair electrons, APTO has 1 lone-pair electrons, and APTDO completely loses its lone-pair electrons. Based on the exciplex formation, the monomers APTO, APTDO, ACPO, and ACPTDO could act as sensitizers for the photopolymerization of acrylonitrile (AN). The combination of APTO or ACPTO with organic peroxides such as BPO could also initiate the polymerization of vinyl monomers, such as AN, by redox nature. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 1191–1199, 1998

The crystal/melt interface shape is an important factor in determining the crystal quality during crystal growth. To determine the evolution of the interface shape, the relative temperature gradient function Sv(R) is used as a criterion. This function can be derived from careful analysis of the energy balance at the crystal/melt interface. Some results are presented based on the simplified model of crystal conduction and the Czochralski bulk flow model where the crystal pulling rate is set to zero at a certain crystal length and the growth system is in a steady state.

An acrylic monomer having phenoxazine moiety, i.e., N-acryloylphenoxazine (APO), has been synthesized by dehydrochlorination of N-(3-chloropropionyl)phenoxazine with 1,5-diazabicyclo[5.4.0]undec-5-ene in dimethyl sulfoxide. The monomer can be polymerized with AIBN as an initiator. The photochemical behavior, including the fluorescence and photosensitizing properties of this monomer and its polymer, has been studied. It has been recorded that the absorption spectrum of polymer P(APO) displays a few blue shifts compared with its monomer APO. It has also been observed that the fluorescence emission intensity of the monomer is dramatically lower than that of its polymer at the same chromophore concentration. This may be ascribed to the charge transfer interacting between the coexisting electron-accepting acrylic carbon-carbon double bond and the electron-donation phenoxazine moiety in APO, intramolecularly or intermolecularly on excitation. The fluorescence of the APO polymer, which does not have carbon-carbon double bond, can be quenched by electron-deficient unsaturated nitriles and esters, clarifying that the electron-deficient carbon-carbon double bond does play an important role for the fluorescence quenching of the monomer. Thus, we term such phenomena as structural self-quenching effect, differing from the concentrational self-quenching effect, which is caused mainly by concentrational factors. The fluorescence quenching of P(APO) by C60 has also been demonstrated. The formation of the charge transfer complex of P(APO) with C60 in the ground state is revealed by the upward deviation from the linearity of the Stern-Volmer plot. APO can act as a photoinitiator to sensitize the photopolymerization of vinyl monomers such as acrylonitrile in dimethyl formamide and pursued kinetically. From the ultraviolet analysis of the PAN sensitized by APO, it is proved that APO not only sensitizes the photopolymerization of AN, but also incorporates in the PAN chain. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:481–489, 1997