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Background: One of the most serious complications of sepsis is sepsis-associated encephalopathy (SAE), which impairs the cognition ability of survivors. Environmental enrichment (EE) has been demonstrated to alleviate cognition deficits under many kinds of brain injury conditions. However, EE's effects on SAE remain unknown. Therefore, this study aimed to determine EE's effect on cognition disorders under SAE conditions and the underlying mechanism. Materials and Methods: Adult male rats, subject to SAE or not, were housed under a standard environment (SE) or EE for 30 days. Subsequently, the rats were subjected to cognitive tests, such as the novel object recognition (NOR) test, the Morris water maze (MWM) test, an Open Field (OF) test, the elevated plus maze (EPM) test, and a sensory neglect (SN) test. Neuroinflammation, apoptosis, and oxidative stress changes in the brain were also detected. Results: The results revealed that SAE impaired somatesthesia, recognition memory, spatial learning and memory, and exploratory activity, which were significantly improved by EE housing. EE also prevented SAE-induced anxiety-like behavior. In addition, EE housing capable induced a decrease in pro-inflammatory cytokines, and an increase in anti-inflammatory cytokines and antioxidant properties in the brain. Moreover, EE housing exerted an anti-apoptosis function by upregulating the level of B-cell lymphoma/leukemia-2 (Bcl-2) level and downregulating the level of p53 level in the hippocampus. Conclusions: The results of the present study indicated that EE exerts a neuroprotective function on cognitive ability in SAE rats. The effect is achieved by increasing antioxidants, and anti-inflammatory and antiapoptotic capacities. EE can effectively rescue SAE-induced cognitive deficits. [ABSTRACT FROM AUTHOR]

Background: Wine is one of the oldest and most popular drinks worldwide, which is rich in phenolic compounds. Epidemiological studies show that moderate consumption of wine can reduce the risk of certain diseases, and this effect is attributed to its phenolic compounds. Objective: The objective of this review was to elaborate the effects of wine-derived phenolic compounds for preclinical anticancer therapeutics and their major mechanisms. Methods: In this review, we discuss the classification and content of common phenolic compounds in wine and summarize previous studies that have evaluated the anticancer properties of wine-derived phenolic compounds and their mechanisms. Results: Wine-derived phenolic compounds have been proven to participate in several mechanisms against cancers, including deoxyribonucleic acid damage, oxidative stress, cell proliferation, cell cycle arrest, cell apoptosis, autophagy, cell invasion and metastasis, immunity and metabolism, regulation of multiple signaling molecules, and gene expression. However, the exact anticancer mechanisms of the phenolic compounds in wine need to be further investigated. Conclusion: Wine-derived phenolic compounds are promising chemoprotective and chemotherapeutic agents for cancer. [ABSTRACT FROM AUTHOR]

Backgrounds/Aims: It has been reported that myocardial infarction (MI) is a risk factor for vascular dementia. However, the molecular mechanism remains largely unknown. Methods: MI mice were generated by ligation of the left coronary artery (LCA) for 4 weeks. Passive and active avoidance tests were performed to evaluate the cognitive ability of MI mice. A theta-burst stimulation (TBS) protocol was applied to elicit long-term potentiation (LTP) of the perforant pathway-dentate gyrus synapse (PP-DG). Western blot analysis was employed to assess protein levels. Results: In this study, we demonstrated that after 4 weeks of MI, C57BL/6 mice had significantly impaired memory. Compared with the sham group, in vivo physiological recording in the MI group revealed significantly decreased amplitude of population spikes (PS) with no effect on the latency and duration of the stimulus-response curve. The amplitude of LTP was markedly decreased in the MI group compared with the sham group. Further examination showed that the expression of the TBS-LTP-related proteins BDNF, GluA1 and phosphorylated GluA1 were all decreased in the MI group compared with those in the sham group. Strikingly, all these changes were prevented by hippocampal stereotaxic injection of an anti-miR-1 oligonucleotide fragment carried by a lentivirus vector (lenti-pre- AMO-1). Conclusion: MI induced cognitive decline and TBS-LTP impairment, and decreased BDNF and GluA1 phosphorylation levels from overexpression of miR-1ated were involved in this process. [ABSTRACT FROM AUTHOR]

Saprolegniosis is an infectious disease caused by Saprolegnia sp. It may cause serious losses in fish farms and hatcheries in many countries. In previous research, Magnolia officinalis has been found to initiate the death of Saprolegnia sp. Magnolol and honokiol, two active substances in M. officinalis, may be responsible for the antifungal effects on Saprolegnia sp. The present study centered on the anti-fungal activity and mechanism of magnolol and honokiol on Saprolegnia parasitica. Results revealed that magnolol and honokiol displayed effective anti-fungal activity on S. parasitica, which caused their mass mortality. More intuitive research has shown that magnolol and honokiol have evolved mechanisms that can destroy the cell membranes of S. parasitica, and cause exosmosis of their cytoplasmic saccharides and proteins, and cause mortality. Magnolol and honokiol exhibited minimum inhibitory concentration values of 976.6 ug/mL and 587.4 ug/mL concentrations, respectively, and the minimum inhibitory time of both was 2 hours. This study provides a clearer understanding of the function of M. officinalis against Saprolegnia sp. [ABSTRACT FROM AUTHOR]

In this paper, we review the current knowledge regarding factors affecting the outbreaks of saprolegniosis. Saprolegniosis is a serious disease which can cause significant economic losses in aquaculture. Oomycetes are considered to be responsible for the disease. Outbreaks of saprolegniosis occur when equilibrium between pathogenic oomycetes and host resistance is disturbed. This may be the result of an increase in numbers or virulence of the zoospores of oomycetes in the water, or an increase in the susceptibility of the host. The presence of oomycetes zoospores in the environment is regarded as one of the most important causes of saprolegniosis. However, important differences have been found between plant and animal pathogenic oomycetes and appear to be related not only to tactic responses to environment, but also to infection strategies to a host. In addition, fish are more susceptible to infection by pathogenic oomycetes when physically injured, stressed or infected. Furthermore, water environmental factors, such as temperature, salinity, and microorganisms, should be carefully considered since they play a key role in the outbreaks of saprolegniosis. [ABSTRACT FROM AUTHOR]

A test strip, based on DNA-functionalized gold nanoparticles for Hg2+ detection, has been developed, optimized and validated. The developed colorimetric mercury sensor system exhibited a highly sensitive and selective response to mercury. The measurement principle is based on thymine一Hg2+一thymine (T一Hg2+一T) coordination chemistry and streptavidin–biotin interaction. A biotin-labeled and thiolated DNA was immobilized on the gold nanoparticles (AuNPs) surface through a self-assembling method. Another thymine-rich DNA, which was introduced to form DNA duplexes on the AuNPs surface with thymine一Hg2+一thymine (T一Hg2+一T) coordination in the presence of Hg2+, was immobilized on the nitrocellulose membrane as the test zone. When 一Hg2+一 ions were introduced into this system, they induced the two strands of DNA to intertwist by forming T一Hg2+一T bonds resulting in a red line at the test zone. The biotin-labeled and thiolated DNA-functionalized AuNPs could be captured by streptavidin which was immobilized on the nitrocellulose membrane as the control zone. Under optimized conditions, the detection limit for Hg2+ was 3 nM, which is lower than the 10 nM, maximum contaminant limit defined by the US Environmental Protection Agency (EPA) for drinking water. A parallel analysis of Hg2+ in pool water samples using cold vapor atomic absorption spectrometry showed comparable results to those obtained from the strip test. Therefore, the results obtained in this study could be used as basic research for the development of Hg2+ detection, and the method developed could be a potential on-site screening tool for the rapid detection of Hg2+ in different water samples without special instrumentation. All experimental variables that influence the test strip response were optimized and reported. [ABSTRACT FROM AUTHOR]

Energy consumption increases with urbanisation. This paper developed evaluation indicators and calculations for energy consumption changes, and advances a new indicator, Energy Consumption Unit Geometric Average (ECUGA) elasticity coefficient and its calculation. The ECUGA elasticity coefficient can explore energy consumption changes and make comparisons among countries at different urbanisation stages. The general trend of energy consumption changes is summarised at different urbanisation stages based on values for 45 countries. For China, the ECUGA elasticity coefficient first increases and then decreases, with the peak of urbanisation at 40% to 50%. China's ECUGA elasticity coefficient for 1978-2005 and 2010-2050 differed from the general trend, with a decrease until urbanisation reached 40%, followed by a rapid increase at 40% to 50%, and then a decrease from 50% to 80%. Although the increase and decrease of China's ECUGA elasticity coefficient is faster than in other countries, the values are always lower than the average for these countries at corresponding urbanisation stages. [ABSTRACT FROM AUTHOR]

Better understanding and evaluation of ecosystem services are important for applying the correct model of regional development planning. Using the physical assessment method (PAM) and the value assessment method (VAM), the ecosystem services in Lugu Lake watershed, including product supply, soil conservation, water conservation, CO2 absorption, O2 release, nutrient cycle, flood storage and ecotourism, were evaluated and analysed. The results show that the total economic value of these ecosystem services was 500.68 x 106 Yuan/a (at comparable prices in 2004); ecotourism was the major component of ecosystem services, accounting for 41.6%; the values of O2 release, flood storage, CO2 absorption and water conservation accounted for 28.1, 13.7, 7.7, and 5.5%, respectively; the value of product supply accounted for only 2.4% and, therefore, was not a major part of watershed ecosystem services. Sustainable development of ecotourism and long-term preservation of the functions of O2 release and flood storage need to be assured for realising ecosystem services of Lugu Lake watershed. [ABSTRACT FROM AUTHOR]

Zinc and RING finger 3 (ZNRF3) is a negative-feedback regulator of Wnt/β-catenin signaling, which plays an important role in human brain development. Although somatically frequently mutated in cancer, germline variants in ZNRF3 have not been established as causative for neurodevelopmental disorders (NDDs). We identified 12 individuals with ZNRF3 variants and various phenotypes via GeneMatcher/Decipher and evaluated genotype-phenotype correlation. We performed structural modeling and representative deleterious and control variants were assessed using in vitro transcriptional reporter assays with and without Wnt-ligand Wnt3a and/or Wnt-potentiator R-spondin (RSPO). Eight individuals harbored de novo missense variants and presented with NDD. We found missense variants associated with macrocephalic NDD to cluster in the RING ligase domain. Structural modeling predicted disruption of the ubiquitin ligase function likely compromising Wnt receptor turnover. Accordingly, the functional assays showed enhanced Wnt/β-catenin signaling for these variants in a dominant negative manner. Contrarily, an individual with microcephalic NDD harbored a missense variant in the RSPO-binding domain predicted to disrupt binding affinity to RSPO and showed attenuated Wnt/β-catenin signaling in the same assays. Additionally, four individuals harbored de novo truncating or de novo or inherited large in-frame deletion variants with non-NDD phenotypes, including heart, adrenal, or nephrotic problems. In contrast to NDD-associated missense variants, the effects on Wnt/β-catenin signaling were comparable between the truncating variant and the empty vector and between benign variants and the wild type. In summary, we provide evidence for mirror brain size phenotypes caused by distinct pathomechanisms in Wnt/β-catenin signaling through protein domain-specific deleterious ZNRF3 germline missense variants. [Display omitted] Boonsawat et al. establish germline missense variants in the tumor suppressor gene ZNRF3 as a cause of neurodevelopmental disorders (NDDs) with microcephaly or macrocephaly, depending on the functional/domain-specific effects of the variants on Wnt/β-catenin signaling. This study finds that ZNRF3 haploinsufficiency does not cause NDDs but rather other phenotypes. [ABSTRACT FROM AUTHOR]

Anticancer activity and toxicity of doxorubicin (Dox) are associated with its DNA intercalation. To understand the role in gene regulation and the drug mechanism, it is a challenge to detect the DNA–Dox interaction at the single-molecule level without the use of laborious, time-consuming labeling assays and an error-prone amplification method. Here, we utilized the simplest and cheapest, yet highly sensitive, single-molecule nanopore technology to investigate the DNA–Dox interaction and explore in situ the intercalative reaction kinetics. Distinctive electronic signal patterns between DNA and the DNA–Dox complex allow protein nanopore to readily detect the changes in structure and function of DNA. After Dox insertion, nanopore unzipping time of DNA was elevated 10-fold while the blocking current decreased, demonstrating the higher affinity of the DNA–Dox complex (formation constant Kf = 3.09 × 105 M-1). Continuous rapid nanopore detection in real time displayed that Dox intercalation in DNA is a two-state dynamic process: fast binding and slow conformational adaption. The nanopore platform provides a powerful tool for studying small molecule–biomacromolecule interactions and paves the way for novel applications aimed at drug screening and functional analysis. [ABSTRACT FROM AUTHOR]

We first study the reversibility for a class of states under the operations which completely preserve the positivity of partial transpose (PPT) and show that the entanglement cost is equal to the distillable entanglement for a rank-two mixed state on the 4⊗4 antisymmetric subspace under PPT operations. By using a similar method in finding the irreversibility, we also find that the value of a new efficiently computable additive lower bound Eη(ρ) for the asymptotic PPT-relative entropy of entanglement presented in [Phys. Rev. Lett.119, 180506 (2017)] is equal to the regularized Rains’ bound and an upper bound EN(ρ) for distillable entanglement for these states. Furthermore, we find states on the symmetric subspace satisfying the relation mentioned above, generalize the antisymmetric states and symmetric states in higher dimensions, and give a specific value for distillable entanglement and entanglement cost for these states under the PPT operations. [ABSTRACT FROM AUTHOR]

In the developing cortex, excitatory neurons migrate along the radial fibers to their final destinations and build up synaptic connection with each other to form functional circuitry. The shaping of neuronal morphologies by actin cytoskeleton dynamics is crucial for neuronal migration. However, it is largely unknown how the distribution and assembly of the F-actin cytoskeleton are coordinated. In the present study, we found that an actin regulatory protein, coronin 2B, is indispensable for the transition from a multipolar to bipolar morphology during neuronal migration in ICR mice of either sex. Loss of coronin 2B led to heterotopic accumulation of migrating neurons in the intermediate zone along with reduced dendritic complexity and aberrant neuronal activity in the cortical plate. This was accompanied by increased seizure susceptibility, suggesting the malfunction of cortical development in coronin 2B-deficient brains. Coronin 2B knockdown disrupted the distribution of the F-actin cytoskeleton at the leading processes, while the migration defect in coronin 2B-deficient neurons was partially rescued by overexpression of Rac1 and its downstream actin-severing protein, cofilin. Our results collectively reveal the physiological function of coronin 2B during neuronal migration whereby it maintains the proper distribution of activated Rac1 and the F-actin cytoskeleton. [ABSTRACT FROM AUTHOR]

Meiyu front precipitation makes the region prone to frequent floods, mudslides, landslides, and other disasters and has been the focus of ongoing and challenging meteorological research. Investigation of the Raindrop size distribution (RSD) is essential for exploring the characteristics and underlying physical precipitation processes. In this study, the precipitation characteristics in Lushan mountainous areas during the Meiyu season were investigated using laser disdrometer observed RSD data from 2016 to 2020. For the average spectra of five rain rate classes, the concentrations of large raindrops (> 0.5 mm) increased with rain rate (R), whereas the concentrations of small raindrops (< 0.5 mm) increased only under rain rates higher than 10 mm h-1. The gamma distribution parameters of N0 (intercept parameter) and Λ (slope parameter) increased/decreased with rain rate, and the shape parameter µ exhibited negative values in different rain rate classes. The distribution pattern features were N (D) = 721D-1.79e-1.20D. Distributions of the frequency for mass-weighted mean diameter (Dm) and the logarithm of the generalized intercept parameter (log10 Nw) both showed a unique bimodal type, and an exceptionally high Nw (log10 Nw > 4.5) subset with small Dm was determined. The stratiform and convective rains of RSD were also investigated. Dm - R and Nw - R showed similar variations in two types of precipitation. The lower µ values resulted in higher primary and constant coefficients in the quadratic polynomial fitting for the µ relationship (Λ = 0.0347µ2 + 1.180µ + 2.495). The Z - R relationship (Z for radar reflectivity factor) in stratiform precipitation characteristics was Z = 203R1.59. Further investigations showed that high Nw values usually occurred in persistent precipitation. The RSD can be characterized as high concentrations of the first two diameter classes with a narrow spectrum width (< 1 mm), which were captured during in-cloud rain with a low but continuous rain rate (< 5 mm h-1). The mountainous topography plays an important role in reshaping the characteristics of RSD and physical processes of precipitation. [ABSTRACT FROM AUTHOR]

Lugu Lake region not only has a plateau lake, which has important ecological functions, but also a unique matriarchal culture and Axia marriage. The natural ecology and water quality in Lugu Lake region have remained good for generations, not only because of the relatively closed geography and local economic underdevelopment but also because of the local Mosuo culture. To understand the relationship between the Mosuo culture and protection of the local environment, it is necessary to understand current Mosuo ideology and life styles in relation to potential environmental change. We undertook an investigation from 2004-2006 in the Lugu Lake region, talking to many Mosuo families and tourists. A questionnaire survey was conducted, with 136 questions for Mosuo families and 72 questions for tourists. Analysis of the results indicates that the Mosuo matriarchal families, Axia marriage, traditional religious beliefs and life style have played an important role in natural resources use, population control and environmental protection. Recently, with the rapid development of transportation and tourism, communication between Lugu Lake region and the outside has increased, leading to changes in traditional Mosuo culture and ideology that affect their roles in environmental protection. Changes in Mosuo ideology, family, marriage form, production system, life style, environmental consciousness and protection motivation may profoundly impact the local environment. Thus, careful development of Mosuo culture is essential to harmonise its relationship with the environment and regional sustainable development. [ABSTRACT FROM AUTHOR]

Mooring measurements at ;1408E in the western equatorial Pacific Ocean documented greatly intensified eastward subsurface currents, which largely represent the nascent Equatorial Undercurrent, to ~67 cm s-1 in boreal summer of 2016. The eastward currents occupied the entire upper 500m while the westward surface currents nearly disappeared. Historical in situ data observed similar variations after most El Niño events. Further analysis combining satellite and reanalysis data reveals that the eastward currents observed at ~1408E are a component of an anomalous counterclockwise circulation straddling the equator, with westward current anomalies retroflecting near the western boundary and feeding southeastward current anomalies along the New Guinea coast. A 1.5-layer reduced-gravity ocean model is able to crudely reproduce these variations, and a hierarchy of sensitivity experiments is performed to understand the underlying dynamics. The anomalous circulation is largely the delayed ocean response to equatorial wind anomalies over the centralto- eastern Pacific basin emerging in the mature stage of El Niño. Downwelling Rossby waves are generated by the reflection of equatorial Kelvin waves and easterly winds in the eastern Pacific. Upon reaching the western Pacific, the southern lobes of Rossby waves encounter the slanted New Guinea island and deflect to the equator, establishing a local sea surface height maximum and leading to the detour of westward currents flowing from the Pacific interior. Additional experiments with edited western boundary geometry confirm the importance of topography in regulating the structure of this cross-equatorial anomalous circulation. [ABSTRACT FROM AUTHOR]

Multi-time-scale variabilities of the Indian Ocean (IO) temperature over 0–700m are revisited from the perspective of vertical structure. Analysis of historical data for 1955–2018 identifies two dominant types of vertical structures that account for respectively 70.5% and 21.2% of the total variance on interannual-to-interdecadal time scales with the linear trend and seasonal cycle removed. The leading type manifests as vertically coherent warming/cooling with the maximal amplitude at; 100m and exhibits evident interdecadal variations. The second type shows a vertical dipole structure between the surface (0–60 m) and subsurface (60–400 m) layers and interannual-to-decadal fluctuations. Ocean model experiments were performed to gain insights into underlying processes. The vertically coherent, basinwide warming/cooling of the IO on an interdecadal time scale is caused by changes of the Indonesian Throughflow (ITF) controlled by Pacific climate and anomalous surface heat fluxes partly originating from external forcing. Enhanced changes in the subtropical southern IO arise from positive air–sea feedback among sea surface temperature, winds, turbulent heat flux, cloud cover, and shortwave radiation. Regarding dipole-type variability, the basinwide surface warming is induced by surface heat flux forcing, and the subsurface cooling occurs only in the eastern IO. The cooling in the southeast IO is generated by the weakened ITF, whereas that in the northeast IO is caused by equatorial easterly winds through upwelling oceanic waves. Both El Niño–Southern Oscillation (ENSO) and IO dipole (IOD) events are favorable for the generation of such vertical dipole anomalies. [ABSTRACT FROM AUTHOR]

Organic aerosol (OA) constitutes a large fraction of fine particulate matter (PM) in the urban air. However, the chemical nature and sources of OA are not well constrained. Quantitative analysis of OA is essential for understanding the sources and atmospheric evolution of fine PM, which requires accurate quantification of some organic compounds (e.g., markers). In this study, two analytical approaches, i.e., thermal desorption (TD) gas chromatography-mass spectrometry (GC-MS) and solvent extract (SE) GC-MS were evaluated for the determination of n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and hopanes in ambient aerosol. For the SE approach, the recovery obtained is 89.3-101.5 %, the limits of detection (LOD) are 0.05-1.1 ng (1.5-33.9 ng m-3), repeatability is 3.5-14.5 % and reproducibility is 1.2-10.9 %. For the TD approach, the recovery is 57.2-109.8 %, the LODs are 0.1-1.9 ng (0.04-0.9 ng m-3), repeatability is 2.1-19.4 % and reproducibility is 1.1-12.9 %. Ambient aerosol samples were collected from Beijing, Chengdu, Shanghai, and Guangzhou, during the winter of 2013 and were analyzed by the two methods. After considering the recoveries, the two methods show a good agreement with a high correlation efficient (R² > 0.98) and a slope close to unity. The concentrations of n-alkanes, PAHs, and hopanes are found to be much higher in Beijing than those in Chengdu, Shanghai, and Guangzhou, most likely due to emissions from coal combustion for wintertime heating in Beijing. [ABSTRACT FROM AUTHOR]

Background: From 1973 to 2005, the lung cancer mortality in Xuanwei had increased constantly. Effect analysis of age and non-age factors on lung cancer is important for local policy-making.Methods: Demographic and death data was collected and used. Factors of lung cancer were classified into age and non-age factors. The contribution of the two factors to lung cancer was evaluated by method of decomposing the differences of mortality rate.Results: For males, the non-age factors were the major contributor to growth of lung cancer mortality, and 78.46% of all growth was attributed to non-age factors. For females, the non-age factors were the absolute contributor to growth of lung cancer in 1973-1992. From 1992 to 2005, the contribution proportion had reduced to 75.39%.Conclusions: Aging was one of risk factors for lung cancer in Xuanwei, but not the main factor. It was supposed that multiple environmental risk factors were related with high growth of lung cancer in Xuanwei. Policy-making should focus on the non-age factors. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is one of the most common neurodegenerative disorders of aging, characterized by the degeneration of dopamine neurons (DA neurons) in the substantial nigra, leading to the advent of both motor symptoms and non-motor symptoms. Current treatments include electrical stimulation of the affected brain areas and dopamine replacement therapy. Even though both categories are effective in treating PD patients, the disease progression cannot be stopped. The research advance into cell therapies provides exciting potential for the treatment of PD. Current cell sources include neural stem cells (NSCs) from fetal brain tissues, human embryonic stem cells (hESCs), induced pluripotent stem cells (iPSCs) and directly induced dopamine neurons (iDA neurons). Here, we evaluate the research progress in different cell sources with a focus on using iPSCs as a valuable source and propose key challenges for developing cells suitable for large-scale clinical applications in the treatment of PD. [ABSTRACT FROM AUTHOR]

Background aims. Since human embryonic stem cells and human fetal neural stem cells have immune rejection and ethical issues, recent advancements in induced pluripotent stem cells (iPS cells) provide new possibilities to study autologous cell therapy for Parkinson's disease (PD). Methods. We isolated human skin fibroblasts from normal individuals and patients with PD; we generated iPS cells by transfecting these human skin fibroblasts with retroviral reprogramming factors of OCT4, SOX2, KLF4 and c-MYC and induced iPS cells to differentiate neural stem cells (NSCs) and then into neurons and dopamine neurons in vitro. Results. We found that iPS cell--derived NSC transplant into the striatum of the 6-hydroxydopamine (OHDA)--induced PD rats improved their functional defects of rotational asymmetry at 4, 8, 12 and 16 weeks after transplantation. iPS cell--derived NSCs were found to survive and integrate into the brain of transplanted PD rats and differentiated into neurons, including dopamine neurons in vivo. Conclusions. Transplantation of iPS cell--derived NSCs has therapeutic potential for PD. Our study provided experimental proof for future clinical application of iPS cells in cell-based treatment of PD. [ABSTRACT FROM AUTHOR]

In this work, a highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed by using molecularly imprinted polymer (MIP) particles as quasi-ionophore. The water-compatible MIP particles targeting tetracycline were synthesized with tetracycline as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2′-azobisisobutyronitrile as an initiator and lanthanum ion as a mediator. Benefited from the distinctive performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower detection limit of the electrode was decreased to about 1 × 10 mol/l. It exhibited a good electrode slope 59.8 mV/decade near the theoretical Nernstian one, with a wide linear working range from 2.0 × 10 to 1.0 × 10 mol/l. Due to the specific recognition of tetracycline by the MIP particles, the selectivity coefficients for routine interferences were less than 10. The fabricated electrode should be used in pH 2-4, response time of which was less than 200 s when the concentration of tetracycline was higher than 1.0 × 10 mol/l and no more than 30 min at the concentration of 1.0 × 10 mol/l. Finally, the proposed highly-sensitive ion selective electrode has been successfully applied to the determination of tetracycline in aqueous samples. [ABSTRACT FROM AUTHOR]

Cytochrome c (cyt- c) entrapped in agarose hydrogel was electrostatically bound to the edge plane pyrolytic graphite electrode (EPPGE), and then stable agarose-cyt- c/EPPGE was prepared. Direct electrochemistry between cyt- c and the EPPGE was monitored by protein film voltammetry. The effects of ionic strength, pH and exterior substances on the direct electrochemistry, and electrocatalytic properties of cyt- c were also studied. Results show that the electrochemical behavior of heme Fe(III)/Fe(II) in cyt- c is quasireversible. Its electrochemical performance is the best when the concentration of supporting electrolyte phosphate buffer solution is 0.2 mol/l and pH is 7.0, and greatly inhibited by exterior metal ions. Catalytic reduction of oxygen could also be achieved at the agarose-cyt- c/EPPGE. [ABSTRACT FROM AUTHOR]

This paper studies the magnetic hysteresis and refrigeration capacity of Ni-Mn-Ga alloys in detail during heating and cooling isothermal magnetisation processes. The Ni-Mn-Ga alloys show larger magnetic hysteresis when they transform from austenite to martensite, but smaller magnetic hysteresis when they transform from martensite to austenite. This behaviour is independent of either the pure Ni-Mn-Ga alloys or the alloys doped with other elements. Because of the existence of the magnetic hysteresis, the relation between the magnetic entropy change and refrigeration capacity is not simply linear. For practical consideration, magnetocaloric effect of Ni-Mn-Ga alloys should be investigated both on cooling and heating processes. [ABSTRACT FROM AUTHOR]

Abstract: The photothermolysis of living EMT-6 breast tumor cells triggered by gold nanorods (AuNRs) with two-photon irradiation was conducted in situ and under real-time observation. The morphology and plasma membrane permeability of the cells were key indicators to the phenomena. AuNRs with an aspect ratio of 3.92, and a longitudinal absorption peak at 800 nm were synthesized with a seed-mediated method. The nanorods surfaces were further modified with polystyrenesulfonate (PSS) for biocompatibility. The prepared nanorods displayed excellent two-photon photoluminescence imaging. In situ real-time results revealed cavities internal to the cells were created from thermal explosions triggered by AuNRs localized photothermal effect. The cavitation dynamic is energy dependent and responsible for the perforation or sudden rupture of the plasma membrane. The energy threshold for cell therapy depended significantly on the number of nanorods taken up per cell. For an ingested AuNR cluster quantity N ∼ 10–30 per cell, it is found that energy fluences E larger-than 93 mJ/cm2 led to effective cell destruction in the crumbled form within a very short period. As for a lower energy level E = 18 mJ/cm2 with N ∼ 60–100, a non-instant, but progressive cell deterioration, is observed. [Copyright &y& Elsevier]