Dynamic Cantilever Magnetometry of Paramagnetism with Slow Relaxation

Dynamic cantilever magnetometry is a sensitive method that has been widely used in studying magnetic anisotropy in ferromagnetic materials and Fermi surface in quantum materials.We study a cobalt-iridium metal-metalloligand coordination polymer using dynamic cantilever magnetometry.The experimental data of dynamic cantilever magnetometry are well explained using the proposed model for Langevin paramagnetism with slow relaxation.Based on the proposed model,we calculate the magnetization and magnetic susceptibility of paramagnetic materials from frequency shifts of a cantilever.The extracted magnetization and magnetic susceptibility are consistent with those obtained from conventional DC and AC magnetometry.The proposed slow relaxation picture is probably a general model for explaining dynamic cantilever magnetometry data of paramagnetic materials,including previously observed dynamic cantilever magnetometry data of paramagnetic metals[Gysin et al.2011 Nanotechnology22285715].

Influencing Factors of Rural Land Internal Circulation Market in Guangdong Province

The circulation of rural land is helpful to improving the allocation efficiency of land resources,increasing farmers'income and promoting the development of modern agriculture.In this paper,we used the social economy,the main participants and the market environment of rural land circulation to make a qualitative analysis for the factor of rural land internal circulation.With the aid of principal component analysis,grey correlation model,and other methods to make a quantitative analysis for the factor of rural land internal circulation.The results show that the grey correlation degrees of the output value of secondary and tertiary industries as a proportion of GDP,the expenditure on science and education per capita,the expenditure on financial support for agriculture,the proportion of non-agricultural population and the standardization of rural land circulation contracts are 0.8988,0.8382,0.7632 and 0.7576 respectively,indicating that these factors are significantly related to the rural internal land circulation market.

Construction of Expression Vector for Porcine Gastrin-releasing Peptide Fusion Protein

[Objectives]This study was conducted to obtain porcine gastrin-releasing peptide(GRP)fusion protein.[Methods]The constructed pET32a(+)-GRP plasmid was transformed into Escherichia coli BL21(DE3)competent cells to obtain the pET32a(+)-GRP-BL21(DE3)fusion protein expression strain,which was induced with 0.5 mM IPTG at 25℃and 150 r/min for 12 h,and the His-tagged GRP fusion protein was detected by SDS-Page gel electrophoresis and Western Blot.[Results]After optimizing the IPTG-induced expression conditions,it was confirmed that the porcine GRP fusion protein was obtained,and the porcine GRP fusion protein was soluble,stable and highly active.[Conclusions]This study lays a foundation for the subsequent preparation of anti-pig GRP antibodies.

Effects of LPS on the Gene Expression of NMB and Its Receptor in the Hypothalamic-pituitary-testicular Axis of Rabbits

[Objectives]This study was conducted to investigate the effect of lipopolysaccharide(LPS)on the gene expression levels of neuromedin B(NMB)and its receptor(NMBR)in the hypothalamic-pituitary-testis(HPT)axis of male rabbits.[Methods]Forty male New Zealand white rabbits were randomly divided into an experimental group injected with LPS and a control group.At 0,1.5,3,6 and 12 h after LPS injection,four rabbits in each group were sacrificed,and the hypothalamus,pituitary and testicular tissues were collected.RT-PCR was carried out to detect the expression of rabbit NMB and NMBR mRNA in the HPT axis.[Results]NMB and NMBR mRNA were expressed in the hypothalamus,pituitary gland and testis of rabbits,and there was a certain time effect,indicating that the NMB/NMBR system is involved in the activities of the hypothalamus-pituitary-testis(HPT)axis.At 1.5 h after LPS stimulation,the expression of NMB mRNA in the hypothalamus increased significantly,and showed an extremely significant difference from the control group(P<0.01),while the expression of NMBR mRNA in the hypothalamus increased,but was not significantly different from the control group(P>0.05).The expression levels of NMB and NMBR mRNA in the pituitary and testis tissues in the HPT axis at different time after the LPS treatment were not significantly different from those in the control group(P>0.05).Therefore,LPS stimulation still has a certain effect on the expression of NMB and its receptor mRNA in the HPT axis.[Conclusions]This study is of great significance for the in-depth study on the mechanism of damage caused by immune stress to livestock and poultry reproduction.

No tillage outperforms conventional tillage under arid conditions and following fertilization

Reduced tillage practices present a tool that could sustainably intensify agriculture.The existing literature,however,lacks a consensus on how and when reduced tillage practices should get implemented.We reanalyzed here an extensive dataset comparing how regular tillage practices(i.e.,conventional tillage)impacted yield of eight crops compared to stopping tillage altogether(i.e.,no-tillage practice).We observed that aridity and fertilization favored no tillage over conventional tillage whereas conventional tillage performed better under high fertility settings.We further show that the responses are consistent across the crops.Our reanalysis complements the original and fills a gap in the literature questioning the conditions under which reducing tillage presents a viable alternative to common tillage practices.

Structure,defects,and microwave dielectric properties of Al-doped and Al/Nd co-doped Ba_(4)Nd_(9.33)Ti_(18)O_(54)ceramics

Low-loss tungsten–bronze microwave dielectric ceramics are dielectric materials with potential application value for miniaturized dielectric filters and antennas in the fifth-generation(5G)communication technology.In this work,a novel Al/Nd co-doping method of Ba_(4)Nd_(9.33)Ti_(18)O_(54)(BNT)ceramics with a chemical formula of Ba_(4)Nd_(9.33+z/3)Ti_(18−z)Al_(z)O_(54)(BNT–AN,0≤z≤2)was proposed to improve the dielectric properties through structural and defect modulation.Together with Al-doped ceramics(Ba_(4)Nd_(9.33)Ti_(18−z)Al_(4z/3)O_(54),BNT–A,0≤z≤2)for comparison,the ceramics were prepared by a solid state method.It is found that Al/Nd co-doping method has a significant effect on improving the dielectric properties compared with Al doping.As the doping amount z increased,the relative dielectric constant(εr)and the temperature coefficient of resonant frequency(τf)of the ceramics decreased,and the Q×f values of the ceramics obviously increased when z≤1.5.Excellent microwave dielectric properties ofεr=72.2,Q×f=16,480 GHz,andτf=+14.3 ppm/℃were achieved in BNT–AN ceramics with z=1.25.Raman spectroscopy and thermally stimulated depolarization current(TSDC)technique were firstly combined to analyze the structures and defects in microwave dielectric ceramics.It is shown that the improvement on Q×f values was originated from the decrease in the strength of the A-site cation vibration and the concentration of oxygen vacancies(VO××),demonstrating the effect and mechanism underlying for structural and defect modulation on the performance improvement of microwave dielectric ceramics.