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Group 12 element zinc(II)‐based d10 complexes have long been known for their inherent colorlessness, which has limited their applications in visible light‐driven photophysical and photochemical applications, despite the attractiveness of inexpensive and low‐toxicity zinc metal. Based on precedents with nickel(0) and copper(I) complexes, which also adopt the d10 electronic configuration, achieving a visible light response from zinc(II) complexes seems feasible; however, investigations and proactive design strategies specifically tailored to zinc remain lacking. In this context, the present invited concept paper highlights zinc's potential for visible light responsiveness and evaluates how molecular designs can achieve this capability. After delineating the differences between zinc and other d10 metal centers, we review recent developments in zinc complexes that exhibit visible light absorption and compare these complexes with previously reported colorless complexes to identify key distinctions. This study provides critical insights into the molecular design guidelines that are pivotal for harnessing the emerging potential of zinc for visible light responses. [ABSTRACT FROM AUTHOR]

Electrocatalysts with atomically dispersed metal sites (e.g. metal‐nitrogen‐carbon) have been deemed as promising alternatives for noble‐metal catalysts in couples of electrocatalytic reactions. However, the modulation of such atomic sites and the understanding of their interactions are still highly challenging. Herein, we propose a unique supermolecule assembly‐profile coating strategy to prepare a series of diatomic electrocatalysts by profile coating of eight Prussian blue analogues (PBAs) on supramolecular supports respectively as bimetallic sources. The detailed microstructure analysis revealed that the metal‐nitrogen‐carbon sites with four‐ (Zn−N4) and five‐coordination (Fe−N5) via the nitrogen coordination are similar to the cytochrome c oxidases. For promising electrocatalysis, such unique microstructure is able to activate oxygen molecules due to nitrogen‐bonding coordination with bimetal sites, thus leading to efficient four‐electron oxygen reduction in alkaline, neutral, and acid electrolytes. Especially, zinc group elements (e.g. Zn and Cd) with d10 electron configuration would significantly boost the nitrogen‐bonding coordination with bimetal sites to enhance electrocatalytic activity. The proof‐of‐concept for the general synthesis of advanced electrocatalysts with controllable bimetal active sites and the mechanistic understanding will promote the promising electrocatalysis by applying the similar principles. [ABSTRACT FROM AUTHOR]

Today, lead, bismuth and tin constitute the main group of alloying elements for zinc baths used for hot dip galvanizing. These metals improve the fluidity of liquid zinc, which positively affects the consumption of zinc and improves the appearance of the coating. However, their presence in the bath, despite their beneficial effects, is controversial due to the increased risk of liquid metal-assisted cracking (LMAC). Recent studies also indicate that these additives may contribute to lowering the corrosion resistance of coatings. The article analyzes the existing knowledge on the addition of lead, tin and bismuth to the bath and presents the benefits and limitations of using them as an alloying additive to the hot dip galvanizing bath. [ABSTRACT FROM AUTHOR]

Systematic first principles studies of zinc-chalcogenides have been performed to understand their thermal transport behaviour. We have applied the Boltzmann transport equation in the relaxation time approximation to calculate the thermal conductivity of ZnS, ZnSe, and ZnTe. We find a thermal conductivity cross-over between ZnS and ZnSe at nanostructure sizes around 0.1-0.2 lm and explain this in terms of the different contributions of phonon modes in these materials. We study the effect of nanostructuring using both the diffusive boundary scattering and confined mean free path limit and discuss the variations in the results. Furthermore, we show the strong influence of isotope scattering on the thermal conductivity. The calculated thermal conductivity is found to be strongly dependent on the volume and we explain the observed differences between local density and generalized gradient approximation calculations. We compare further calculated thermal properties, such as the thermal expansion coefficient, to experiment to validate our approach. [ABSTRACT FROM AUTHOR]

In a recent work, the extremely anomalous mechanical behavior of the anhydrous zinc and cadmium oxalates was discovered. In this paper, the mechanical behavior of the anhydrous mercury oxalate containing the remaining transition metal element of the IIB group of periodic table is investigated. The crystal structure and elastic properties of HgC 2 O 4 are determined using first-principles solid-state methods. Although the structure of mercury oxalate and the coordination environment of mercury in this compound are radically different to those of the zinc and cadmium oxalates, a great degree of similarity in their mechanical behavior is unexpectedly found. The mechanical behavior of mercury oxalate is anomalous and exhibits the negative Poisson's ratio (NPR) and the negative linear compressibility (NLC) phenomena. Under isotropic pressure, the compressibility along the [1,0,0] crystallographic direction is negative in the pressure range from − 2.50 to 0.25 GPa. For external pressures applied in the direction of minimum compressibility, which coincides with [1,0,0], mercury oxalate exhibits negative volumetric compressibilities from 0.22 to 1.40 GPa. The increase in volume in this material is significant for pressures larger than 1.0 GPa, and the compressibility becomes − 95.6 TPa - 1 at P = 1.36 GPa. As for the zinc and cadmium oxalates, the increase in volume is so drastic that mercury oxalate becomes unstable for pressures larger than 1.4 GPa. The NLC effect in mercury oxalate is due to the highly deformable character of the cube coordination polyhedron of mercury. The coordination structure becomes octahedral near P = 1.3 GPa, just before its structural instability. [ABSTRACT FROM AUTHOR]

First‐principles simulations can advance our understanding of phase transitions but are often too costly for the heavier elements, which require a relativistic treatment. Addressing this challenge, we recently composed an indirect approach: A precise incremental calculation of absolute Gibbs energies for the solid and liquid with a relativistic Hamiltonian that enables an accurate determination of melting and boiling points (MPs and BPs). Here, we apply this approach to the Group 12 elements Zn, Cd, Hg, and Cn, whose MPs and BPs we calculate with a mean absolute deviation of only 5 % and 1 %, respectively, while we confirm the previously predicted liquid aggregate state of Cn. At a non‐relativistic level of theory, we obtain surprisingly similar MPs and BPs of 650±30 K and 1250±20 K, suggesting that periodic trends in this group are exclusively relativistic in nature. Ultimately, we discuss these results and their implication for Groups 11 and 14. [ABSTRACT FROM AUTHOR]

The aim of this work is to evaluate and compare the possibility of Cd, Hg, Al, Ga, Sn, Pb and Bi as candidate cathode materials based on their physicochemical and electrochemical properties and theoretical separation ability for actinides over lanthanides. First, the comparison of melting points and vapor pressures about those metals shows that Group 12 elements Cd and Zn are more practically suitable for the electrowinning process. Then, cyclic voltammetry conducted at 773 K on these cathodes in LiCl-KCl eutectic presents a trend of electrochemical reactivity (Bi > Sn > Ga ≥ Pb > Zn > Cd > Al), nobility (Bi > Pb ≥ Sn > Ga > Cd > Zn > Al) and electrochemical window (Cd > Al > Pb > Bi > Ga > Sn > Zn), respectively. Moreover, cyclic voltammograms of U3+ and La3+ collected at 773 K on these cathodes demonstrate different electrochemical reactivity scales Ec(U): Ga ≥ Bi > Sn > Al > Zn > Pb > Cd) and Ec(La): Bi > Sn ≥ Ga > Zn > Pb > Cd > Al), respectively, from the anodic to the cathodic side. From these results, a favorable trend for electrochemical separation of U over La can be obtained (Al > Ga > Zn > Bi > Sn > Pb > Cd). In addition, the theoretical Mediema model shows the relationships of the enthalpy of formation and the activity of different alloys as, ${a}_{\left({\rm{U}}-{\rm{M}}\right)}:$ Al < Ga < Sn < Zn < Bi < Pb < Cd, ${a}_{(La-{\rm{M}})}:$ Bi < Sn < Pb < Al < Ga < Cd < Zn, suggests the interaction of Al and Ga to uranium is the strongest with the best theoretical separation performance. [ABSTRACT FROM AUTHOR]

Based on the assumptions that the corresponding states principle is valid for the group 12 dimers and that the interaction potentials of these dimers can be described by the Tang-Toennies potential model, a set of correlation relations between the spectroscopic constants of these dimers are derived. Some recently measured spectroscopic constants satisfy these relations quite well, but older experimental data do not. These recent spectroscopic constants and the newly available dispersion coefficients are used to construct the entire van der Waals potentials of Zn2, Cd2, and Hg2. There are indications that the ground state Hg2 potential predicted by the present study is possibly the most accurate to date. No unequivocal conclusion can be made for Zn2 and Cd2 potentials. Compared with the recent experiments, the present Zn2 bond length is eight percent too small, and the present Cd2 bond length is eight percent too large. However, both Zn2 and Cd2 bond lengths predicted by the present study are in good agreement with the quantum Monte Carlo results. [ABSTRACT FROM AUTHOR]

The term spodium (Sp) bond is proposed to refer to a net attractive interaction between any element of Group 12 and electron‐rich atoms (Lewis bases or anions). These noncovalent interactions are markedly different from coordination bonds (antibonding Sp–ligand orbital involved). Evidence is provided for the existence of this interaction by calculations at the RI‐MP2/aug‐cc‐pVTZ level of theory, atoms‐in‐molecules, and natural bond orbital analyses and by examining solid‐state structures in the Cambridge Structure Database. [ABSTRACT FROM AUTHOR]

• In the HgF 6 molecule, Hg has an unusual oxidation state of +VI. • In the reaction HgF 6 → HgF 4 + 2F, HgF 6 is protected by a barrier height of 22 kcal/mol. • HgF 6 is thermodynamically unstable but kinetically stable, and may exist under certain extreme ambient conditions. As a group 12 element, mercury locating at the sixth row with a valent electronic configuration of 5 d 10 6 s 2 has been treated as a main group element featuring +I and +II oxidation states for a long time. C. K. Jørgensen conjectured the existences of HgF 4 and HgF 6 molecules in early 1960s, where HgF 4 was first synthesized in 2007, but HgF 6 as the Hg(+VI) compound was less known. In this paper we explored the electronic structure and decomposition paths of HgF 6 by scalar (X1C) and 2-component relativistic (X2C) density functional calculations and more accurate multi-reference NEVPT2 calculations. It is found that the HgF 6 molecule, where the mercury atom presents an extraordinary high oxidation state of +VI, is protected by a considerable barrier height of about 22 kcal/mol for the decomposition into HgF 4 and two isolated fluorine atoms. The results propose that HgF 6 is kinetically stable and may exist under exorbitant conditions. [ABSTRACT FROM AUTHOR]

The formation, characterization, and dye sensitized solar cell application of nickel(II), zinc(II) and cadmium(II) ferrocenyl dithiophosphonate complexes were investigated. The multidentate monoanionic ligand [S2PFc(OH)]− (L1) was synthesized. The reaction between metal salt precursors and L1 produced Ni(II) complexes of the type [Ni{S2P(Fc)(OH)}2] (1) (molar ratio 1:2), and a tetranickel(II) complex of the type [Ni2{S2OP(Fc)}2]2 (2) (molar ratio (1:1). It also produced a Zn(II) complex [Zn{S2P(Fc)(OH)}2]2 (3), and a Cd(II) complex [Cd{S2P(Fc)(OH)}2]2 (4). Complexes 1–4 were characterized by 1H and 31P NMR, FTIR and elemental analysis, and complexes 1 and 2 were additionally analyzed by X‐ray crystallography. The first examples of dye‐sensitized solar cells (DSSCs) co‐sensitized with ferrocenyl dithiophosphonate complexes 1–4 are reported. Co‐sensitization with the ruthenium dye N719, produced the dye materials (3)‐N719 (η=8.30%) and (4)‐N719 (η=7.78%), and they were found to have a better overall conversion efficiency than the pure Ru N719 dye standard (η=7.14%) under the same experimental conditions. The DSSCs were characterized using UV/vis, cyclic voltammetry, electrochemical impedance spectroscopy (EIS), photovoltaic‐ (I−V curves), and performing incident photon‐to‐current efficiency (IPCE) measurements. [ABSTRACT FROM AUTHOR]

A molecular dynamics deposition model has been used to simulate the growth of rare gas matrices doped with atoms of the group 12 elements zinc, cadmium and mercury. This study investigates the sites occupied by Zn, Cd and Hg metal atoms when isolated in the solid rare gases. To probe the results, the resonance 1 P 1 ← 1 S 0 transitions of the matrix-isolated metal atoms were calculated and compared with the recorded spectra of the M/RG solids. The theoretical spectroscopy obtained in this work was generated using the molecular dynamics with quantum transitions method. In Ne matrices the metal atoms preferably occupy tetra- and hexa-vacancy sites while in the case of Xe matrices, only the single vacancy site is formed. For Ar and Kr matrices Zn but especially Cd can be trapped in tetra- and hexa-vacancy sites in addition to single-vacancy sites, while Hg atoms show exclusive occupancy in single vacancy sites. [ABSTRACT FROM AUTHOR]

The reaction of 2‐cyanopyridine with N‐phenylthiosemicarbazide afforded 2‐[amino(pyridin‐2‐yl)methylidene]‐N‐phenylhydrazine‐1‐carbothioamide (Ham4ph) and crystals of 4‐phenyl‐5‐(pyridin‐2‐yl)‐2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thione (pyph3NS, 1, C13H10N4S). Crystals of methyl 2‐{[4‐phenyl‐5‐(pyridin‐2‐yl)‐4H‐1,2,4‐triazol‐3‐yl]sulfanyl}acetate (phpy2NS, 2, C16H14N4O2S), derived from 1, were obtained by the reaction of Ham4ph with chloroacetic acid, followed by the acid‐catalyzed esterification of the carboxylic acid with methyl alcohol. Crystals of bis(methanol‐κO)bis(methyl 2‐{[4‐phenyl‐5‐(pyridin‐2‐yl)‐4H‐1,2,4‐triazol‐3‐yl‐κ2N1,N5]sulfanyl}acetato)zinc(II)/cadmium(II) hexabromidocadmate(II), [Zn0.76Cd0.24(C16H14N4O2S)2(CH3OH)2][Cd2Br6] or [Zn0.76Cd0.24(phpy2NS)2(MeOH)2][Cd2Br6], 3, and dichlorido(methyl 2‐{[4‐phenyl‐5‐(pyridin‐2‐yl)‐4H‐1,2,4‐triazol‐3‐yl‐κ2N1,N5]sulfanyl}acetato)mercury(II), [HgCl2(C16H14N4O2S)] or [Hg(phpy2NS)Cl2], 4, were synthesized using ligand 2 and CdBr2 or HgCl2, respectively. The molecular and supramolecular structures of the compounds were studied by X‐ray diffractometry. The asymmetric unit of 3 is formed from CdBr3 and M(phpy2NS)(MeOH) units, where the metal centre M has a 76% occupancy of ZnII and 24% of CdII. The M2+ centre of the cation, located on a crystallographic inversion centre, is hexacoordinated and appears as a slightly distorted octahedral [MN4O2]2+ cation. The Cd centre of the anion is coordinated by two terminal bromide ligands and two bridging bromide ligands that generate [Cd2Br6]2− cadmium–bromide clusters. These clusters display crystallographic inversion symmetry forming two edge‐shared tetrahedra and serve as agents that direct the structure in the formation of supramolecular assemblies. In mononuclear complex 4, the coordination geometry around the Hg2+ ion is distorted tetrahedral and comprises two chloride ligands and two N‐atom donors from the phpy2NS ligand, viz. one pyridine N atom and the other from triazole. In the crystal packing, all four compounds exhibit weak intermolecular interactions, which facilitate the formation of three‐dimensional architectures. Along with the noncovalent interactions, the structural diversity in the complexes can be attributed to the metal centre and to the coordination geometry, as well as to its ionic or neutral character. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Aluminium-manganese binary oxide was coated successfully on raw corncob (RCC) to increase the oxygenic functional groups, and then produced an adsorbent (named as AMOCC). Accordingly, conventional factors, such as dosages, pH values, contact time and temperature, were evaluated for its absorptive properties, while it was characterized by several analytical methods. Moreover, adsorption isotherms, kinetic and thermodynamic analysis were applied to describe its adsorption process, which reflected that Mn O, Mn OH and Al OH were introduced to the positions of hydroxyl (OH) groups, and the O of Mn O and Mn OH could play a significant role in the coordination complex with Cd (II) ions. Moreover, electrostatic interaction occurred at the position of Al OH during adsorption. Therefore, results showed that this adsorbent exhibited the maximum adsorption capacity of 45.58 mg/g, which was higher than RCC and other modified adsorbents previously reported. Further, the Langmiur isotherm and the pseudo-second-order models fitted the experimental data better, and thermodynamic equations revealed the spontaneous and endothermic nature of adsorption. [ABSTRACT FROM AUTHOR]

First-principles calculations have been performed to investigate the doping defects in CuI with group-IIB elements such as Zn, Cd and Hg. The calculated transition energies for substitutional Zn, Cd and Hg are 1.32, 1.28 and 0.60 eV, respectively. These group-IIB elements at the substitutional sites complex with a copper vacancy (V Cu ) have the lower formation energies as compared to dopants located at the substitutional sites or interstitial sites, respectively. Among all the complex defects considered, [ Hg Cu + V Cu ] has the lowest formation energy and it induces the acceptor level 𝜀 (0 / −) = 0. 1 8 eV above the valence-band maximum (VBM), which is close to the acceptor level 𝜀 (0 / −) = 0. 1 eV of V Cu , suggesting that Hg may be a good dopant for CuI to improve its p-type conductivity. [ABSTRACT FROM AUTHOR]

One of the most pressing global concerns is how to provide a clean environment for future generations given the exacerbation of urban, agricultural, industrial, and economic activities due to the escalating size of the global population. A polyamidoamine (PAMAM) dendrimer peripherally modified with 4-N,N′-dimethylethylenediamine-1,8-naphthalmide as a chromophore was synthesized and utilized to capture hazardous heavy metal ions. This modified fluorescent dendrimer (FCD) was complexed with Group 12 metal ions (Zn2+, Cd2+, and Hg2+) at a 2:1 (metal: FCD) ratio. Electronic absorption, fluorescence emission, Infra-red (IR), and nuclear magnetic resonance (1H NMR) spectroscopies, conductivity, CHN elemental, thermogravimetry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses were used to characterize the resulting metal complexes. These assays revealed that the synthesized complexes were yellow-colored, thermally stable, nanoscale-sized, and composed of [M2FCD]·4Cl2. Considerable spectral shifts were observed in the emission and absorption spectra of the FCD molecule after binding the Zn2+ ions, which can be used to differentiate the Zn2+ complex from the other two complexes. This work provides basic data to facilitate the detection, quantification, and removal of environmentally hazardous heavy metal ions through complexation with a fluorescent dendrimer.

Solvent extraction is conducted using a total of 20 di-, tri-, and tetravalent metals, revealing high stability constants with Cl− and the N,N,N′,N′,N″,N″ -hexahexyl-nitrilotriacetamide (NTAamide(C6)) extractant. The metals used here may behave as anions at high Cl− concentrations, and NTAamide(C6), which contains a tertiary N atom, is protonated under acidic conditions. Most of the metal ions in this study display higher distribution ratios (D (M)) from HCl than those from HNO 3 , although NO 3 − hardly forms metal-complexes, and exhibit 1:1 stoichiometries with NTAamide, based on the slopes of acid and metal extraction. The high D (M) may be due to ion-pair extraction based on the combination of cationic extractants and anionic metal-chloride ions. Following the experimental results, the association constants and distribution coefficients of the group 12 elements are calculated via ion-pair extraction modeling using density functional theory calculations, and the simulations of D yield calculated values with the same trend as that of the measured values. In the future, it will be possible to calculate the distribution ratio precisely by considering the size effect in the exosphere of metal and chloride ions and the HSAB rule. • Solvent extraction with N,N,N′,N′,N″,N″ -hexahexyl-nitrilotriacetamide (NTAamide(C6)) extractant is conducted using a total of 20 di-, tri-, and tetravalent metals. • Most of the metal ions exhibit 1:1 stoichiometries with NTAamide, based on the slopes of acid and metal extraction. • The association constants and distribution coefficients of the group 12 elements Zn2+, Cd2+, and Hg2+ are calculated via ion-pair extraction modeling using density functional theory calculations. • The simulations of D yield calculated values with the same trend as that of the measured values. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of N-heterocyclic carbene (NHC) supported group 12 acetate complexes were prepared and their use as building blocks toward soluble group 12 sulfide precursors was explored. The highly moisture-sensitive NHC-ligated zinc dithiolato complex [(IPr)Zn(SSiMe 3) 2 ] was also synthesized [IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene], and its partial hydrolysis gave the dianionic zinc sulfide cluster [Zn 3 (μ 3 -S)(μ 2 -SSiMe 3) 3 (SSiMe 3) 3 ]2−, which contained a rare example of a Zn 3 S structural motif. This preliminary observation indicates that the future growth of related metallosulfide clusters from [(IPr)Zn(SSiMe 3) 2 ] should be possible. [ABSTRACT FROM AUTHOR]

Background: Peanut is the world's fourth largest oilseed crop that exhibits wide cultivar variations in cadmium (Cd) accumulation. To establish the mechanisms of Cd distribution and accumulation in peanut plants, eight cDNA libraries from the roots of two contrasting cultivars, Fenghua 1 (low-Cd cultivar) and Silihong (high-Cd cultivar), were constructed and sequenced by RNA-sequencing. The expression patterns of 16 candidate DEGs were validated by RT-qPCR analysis. Results: A total of 75,634 genes including 71,349 known genes and 4484 novel genes were identified in eight cDNA libraries, among which 6798 genes were found to be Cd-responsive DEGs and/or DEGs between these two cultivars. Interestingly, 183 DEGs encoding ion transport related proteins and 260 DEGs encoding cell wall related proteins were identified. Among these DEGs, nine metal transporter genes (PDR1, ABCC4 and ABCC15, IRT1, ZIP1, ZIP11, YSL7, DTX43 and MTP4) and nine cell wall related genes (PEs, PGIPs, GTs, XYT12 CYP450s, LACs, 4CL2, C4H and CASP5) showed higher expression in Fenghua 1 than in Silihong. Conclusions: Both the metal transporters and cell wall modification might be responsible for the difference in Cd accumulation and translocation between Fenghua 1 and Silihong. These findings would be useful for further functional analysis, and reveal the molecular mechanism responsible for genotype difference in Cd accumulation. [ABSTRACT FROM AUTHOR]

Among heavy metals, Cadmium (Cd) is one of the common pollutants with deleterious reproductive and physiological impact in the biological system. This study was designed to evaluate the detrimental effects of Cd on the seminal and histopathological parameters of the testes; and to explore the therapeutic potentials of the methanolic extract of Gmelina arborea (MEGA) fruit in averting such reproductive damages. To achieve this, a total of 45 rabbit bucks aged between 24-28 weeks and weighing between 1.41-1.43 kg were used. The rabbit bucks were assigned to 5 treatments groups (control, Cd-only, Cd + 300 mg MEGA, Cd + 600 mg MEGA and Cd + 900 mg MEGA) in a completely randomized design. The rabbits were dosed with 3 mg CdCl2 /kg feed for 7 days followed by MEGA for 56 days after every 72 hours before the commencement of semen collection. The result of semen evaluation indicates that semen volume, semen motility, semen concentration, total ejaculate and viability were significantly (P < 0.05) reduced by Cd compared to the control group. Libido, body weight and testis density of the Cd-only rabbit group were also significantly (P < 0.05) reduced. Histopathological examination also revealed severe testicular damage due to Cd. However, treatment with MEGA significantly (P < 0.05) reversed the deleterious reproductive effects caused by Cd. In conclusion, Cd drastically affected the testis of rabbit bucks and treatment with MEGA alleviated these deleterious effects. [ABSTRACT FROM AUTHOR]

Post-transition elements, together with zinc-group metals and their alloys belong to an emerging class of materials with fascinating characteristics originating from their simultaneous metallic and liquid natures. These metals and alloys are characterised by having low melting points (i.e. between room temperature and 300 °C), making their liquid state accessible to practical applications in various fields of physical chemistry and synthesis. These materials can offer extraordinary capabilities in the synthesis of new materials, catalysis and can also enable novel applications including microfluidics, flexible electronics and drug delivery. However, surprisingly liquid metals have been somewhat neglected by the wider research community. In this review, we provide a comprehensive overview of the fundamentals underlying liquid metal research, including liquid metal synthesis, surface functionalisation and liquid metal enabled chemistry. Furthermore, we discuss phenomena that warrant further investigations in relevant fields and outline how liquid metals can contribute to exciting future applications. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) has been identified as a very toxic heavy metal, which is widely present in the environment due to natural and anthropogenic emissions. Currently, in China, slight pollution of cultivated land is widespread and Cd is one of the top ranked inorganic pollutants in soils, which results in a great impact on the development of the economy and society. Therefore, there is an urgent need to develop an efficient and economical method to remediate Cd-polluted soil. This study focused on the development of new kinds of immobilizing soil amendments for the remediation of Cd-polluted soil. In addition, the immobilization capability of zinc (Zn) which may lead to increased toxicity of Cd was also investigated. The amendments, nanoiron-nanohydroxyapatite, nanoalumina-nanoiron and nanohydroxyapatite-nanoalumina, were prepared by the pairwise mixing of three raw materials: nanohydroxyapatite (nHAP), nanoiron (nFe) and nanoalumina (nAl2O3). The application rate, mixing ratio and pH of the amendments were studied to determine the optimal application conditions of the amendments. The results showed that, compared with the single materials of nHAP, nFe and nAl2O3, the immobilized efficiencies of Cd and Zn in soils by the pairwise mixed amendments were both significantly (p < 0.05) increased. Optimal immobilization rates of both Cd and Zn of water-soluble and available fractions were above 97.0%. Scanning electron microscopy illustrated a more uniform mixture can be obtained by wet-mixing compared with a dry-mixing method for nFe-nHAP and nHAP-nAl2O3, and the uniform mixture of nAl2O3-nFe can be obtained by both dry- and wet-mixing methods. Fourier-transform infrared analysis demonstrated that the mixed amendments retained the good capability of nHAP, nFe and nAl2O3 for the stabilization of Cd and Zn in soil. Generally, 4-8% application amount, 4:1 mixing ratio of nFe/nHAP, nAl2O3/nFe and nHAP/nAl2O3, respectively, and neutral or slightly acidic pH of the amendments were optional for the remediation of the studied soil. The order of the three raw nanomaterials that affected on the stabilization capacity of the pairwise mixed amendments was nAl2O3 > nFe > nHAP. [ABSTRACT FROM AUTHOR]

Main conclusion: Heterogeneous expression of the rice genes “fruit-weight 2.2-like” (OsFWL) affects Cd resistance in yeast, and OsFWL4 mediates the translocation of Cd from roots to shoots.Cadmium (Cd) induces chronic and toxic effects in humans. In a previous study (Xu et al. in Planta 238:643-655, 2013), we cloned the rice genes, designated OsFWL1-8, homologous to the tomato fruit-weight 2.2. Here, we show that expression of genes OsFWL3-7 in yeast confers resistance to Cd. The Cd contents of OsFWL3-, -4-, -6- and -7-transformed Cd(II)-sensitive yeast mutant ycf1 cells were strongly decreased compared with those of empty vector, with the strongest resistance to Cd observed in cells expressing OsFWL4. Evaluation of truncated and site-directed mutation derivatives revealed that the CCXXG motifs near the second transmembrane region of OsFWL4 are involved in Cd resistance in yeast. Real-time PCR analysis showed that OsFWL4 expression was induced by CdCl2 stress in rice seedlings. Compared with WT plants, the Cd contents in the shoots of RNAi mediated OsFWL4 knockdown plants were significantly decreased, and Cd translocation from roots to shoots was reduced. According to bimolecular fluorescence complementation, yeast two-hybrid and Western-blotting assays, the OsFWL4 protein forms homo-oligomers. These results suggest that OsFWL4 might act directly as a transporter and is involved in the translocation of Cd from roots to shoots in rice. [ABSTRACT FROM AUTHOR]

Major source for human exposure to cadmium nitrate (Cd(NO3)2) is from smoking and occupational hazard. Cd(NO3)2-induced neurotoxicity and related mechanism in neurons are still unknown. Here, Cd(NO3)2induced cytotoxicity in a concentration- and time-dependent manners on Neuro-2A (N2A) neurons. Genotoxicity, which included micronucleus formation and DNA damage, and caspases, which included caspase-3, -8 and -9, activities were increased by Cd(NO3)2in a concentration-dependent manner. The concentration trends of Cd(NO3)2: 1, 3 and 10 μM, were similar in the significant induction of cytotoxicity and genotoxicity and the up-regulation of the activities of caspase-3, -8, -9. In conclusion, cytotoxicity and genotoxicity were induced by Cd(NO3)2via caspases activities on neurons. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is an environmental electrophile that modifies protein nucleophiles, thereby modulating cellular signaling and toxicity. While reactive persulfides/polysulfides exhibit relatively high nucleophilic properties, their roles in the altered gene expression and toxicity caused by Cd remain unclear. Exposing primary mouse hepatocytes to Cd caused heat shock protein 70 (HSP70) and metallothionein (MT)-I/II to be upregulated and cytotoxicity to occur. These effects were blocked in the presence of polysulfide sodium tetrasulfide (Na2S4). Electrospray ionization mass spectrometry analysis indicated that cadmium sulfide (CdS) and cadmium thiosulfate (CdS2O3) were produced when Cd reacted with Na2S4. Authentic CdS did not cause cellular signaling responses to be activated or hepatotoxic effects, while CdS2O3 had effects similar to those of Cd. HSP70 and MT-I/II upregulation and hepatotoxicity caused by exposure to Cd were significantly enhanced by the deletion of cystathionine γ-lyase (CSE), which catalyzes the formation of reactive persulfides/polysulfides. Deleting CSE also exacerbated Cd-mediated liver injury, whereas little hepatic damage was found when CdS or Na2S4 along with Cd was administered. Overall, the results suggest that the persulfide/polysulfide-mediated formation of sulfur adducts of Cd such as CdS rather than CdS2O3 is, at least in part, involved in decreasing the level of Cd-mediated activation of cellular signaling and toxicity. [ABSTRACT FROM AUTHOR]

Reaction of NiCl2·6H2O, D-camphoric acid (D-H2cam), and N,N'-bis(pyraz-2-yl)piperazine (bpzpip) in pure water at 150 °C afforded a novel nickel(II) coordination layer, [Ni4(D-cam)2(D-Hcam)4(bpzpip)4(H2O)2] (1), under hydro(solvo)thermal conditions. Single-crystal X-ray structure analysis reveals that 1 adopts a six-connected two-dimensional (2D) chiral layer structure with 36-hxl topology. Dye adsorption explorations indicate that 1 readily adsorbs methyl blue (MyB) from water without destruction of crystallinity. On the contrary, methyl orange (MO) is not adsorbed at all. The pseudo-second-order kinetic model could be used to interpret the adsorption kinetics for MyB. Equilibrium isotherm studies suggest complicated adsorption processes for MyB which do not have good applicability for either the two-parameter Langmuir or Freundlich isotherm model. The saturated adsorption capacity of 1 for MyB calculated by Langmuir is 185.5 mg·g-1 at room temperature. [ABSTRACT FROM AUTHOR]

Developing a nonlinear biotic ligand model (BLM) that considers the geometrical constraints for binding of different cations on biotic ligands will provide more reliable details about the hypothetical mechanism governing the alleviation of cadmium (Cd) toxicity by coexistent cations. Soybean seedlings under Cd stress produced by various activities of coexistent cations such as calcium (Ca), magnesium (Mg), and potassium (K) were hydroponically assayed for Cd toxicity to soybean roots. The Cd activity resulting in 50% reduction of root elongation ( RE), EA , was used for assessing the Cd toxicity to the soybean seedling. Increasing Ca, Mg, and K activities resulted in a significant alleviation of Cd toxicity to soybean roots. This alleviation was markedly higher with increasing Ca and K levels than with increasing Mg level. In addition, EA increased in nonlinear positive relationships with Ca and Mg. The real data obtained from the soybean assay were thus used to develop the nonlinear BLM for Cd rhizotoxicity. Two parameters, competition equivalent and stability constant, indicated the profiles of the geometrical constraint and affinity of Ca, Mg, and K binding on the soybean root surface to alleviate Cd toxicity. Compared with the traditional linear BLM, the nonlinear BLM provided more precise predictions of relative root elongation ( RRE) and EA . Therefore, adopting the nonlinear BLM approach will successfully improve the monitoring and assessment of heavy metal toxicity to terrestrial plants. [ABSTRACT FROM AUTHOR]

Zn metal with high theoretical capacity (820 mA h g −1 ), environmental-friendly properties and low cost is very competitive to be as an anode for aqueous batteries. However, uncontrollable growth of dendritic zinc in these batteries during plating/stripping process of zinc ions not only leads to a low Coulombic efficiency but also brings safety hazards, which have obstructed the application of secondary Zn-based batteries. Here we use high conductive carbon fiber-graphite felt (GF) as collector and electrodeposit zinc under constant voltage to fabricate a self-supported Zn@GF negative electrode. The graphite felt provides this anode larger electroactive area to transport electrons faster and loads zinc in a more event way, thus preluding the zinc plating in several specific directions. This composite anode offers an efficient solution to get a dendrite-free cycling behavior of zinc-based batteries and might be promising in advanced aqueous batteries for large-scale energy storage. [ABSTRACT FROM AUTHOR]

Two new zinc-containing complexes [Zn 2 (TEA)(C 6 H 5 COO) 3 ] ( 1 ) and ([Zn(TEA)(H 2 O) 2 ]SO 4 )·H 2 O ( 2 ) were synthesized and characterized by IR spectroscopy, elemental analysis, DSC and TG analysis. Their structure was determined by single-crystal X-ray diffraction. In the binuclear, mixed-ligand [Zn 2 (TEA)(C 6 H 5 COO) 3 ] complex, one zinc atom is six-coordinated by nitrogen and three oxygen atoms of tetradentate triethanolamine (TEA) and two oxygen atoms of two different benzoate ligands, forming the distorted octahedron of the ZnNO5 type. The second zinc atom is five-coordinated, forming the distorted trigonal bipyramid. Two zinc atoms are bridged by two carboxylate groups of two benzoate ligands and one oxygen atom of the deprotonated hydroxyethyl group of TEA. Cationic complex 2 consists of [Zn(TEA)(H 2 O) 2 ] 2+ cations and SO 4 2− anions. The coordination polyhedron around the zinc atom corresponds to a distorted octahedron (ZnNO5 type). The TEA ligand is tetradentately coordinated to the cation, forming three chelate rings. The coordination sphere of the Zn cation is completed by two aqua ligands. [ABSTRACT FROM AUTHOR]

This study was initiated to anticipate the potential protective effects of flavonoid-rich fractions of Hibiscus rosa-sinenses flowers (HF) and leaves (HL) on cadmium (Cd)-induced toxicity in adult albino rabbits. Cd, being a prominent environmental pollutant, poses a threat for its widespread range of toxic expressions. A dramatic increase in total phenolics, flavonoids, and antioxidant capacity has been observed in flavonoid-rich fractions of HF and HL as compared to their crude extracts, suggesting for the rationale for their use in this study. Thirty-six male rabbits were indiscriminately allocated into six groups, including control, Cd (6.1 mg Cd/kg/day), HF and HL (200 mg HF & HL /Kg/day), Cd+HF, and Cd+HL (receiving the same doses of Cd, HF, and HL) groups. Treatment (p.o) for 60 days resulted in improvement of weight gain in Cd+HF and Cd+HL groups in comparison with the Cd group. Treatment with Cd+HF showed better results than Cd+HL by significantly decreasing (p<0.05) transaminases (AST, ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), and creatinine and urea levels, while total bilirubin and albumin were increased on the 15th, 30th, 45th, and 60th days in a progressive manner when compared with the Cd receiving group. Likewise, the Cd+HF group showed better activities than Cd+HL by significantly increasing (p<0.05) superoxide dismutase, catalase, and vitamins C and E, while LPO and Cd concentrations were significantly decreased in the liver and kidney tissues when compared with Cd-intoxicated bucks. Values of these parameters in only HF and HL-receiving groups were near the control. The histopathological studies for these tissues have also sustained the above-mentioned data. Thus, these outcomes suggest that the flavonoid-rich fraction of HF may act as a potent hepatic and renal protective agent than HL against Cd-induced toxicity in animal models. [ABSTRACT FROM AUTHOR]

Field measurements were performed using a LUMEX RA-915+ mercury vapour analyser to determine the gaseous mercury (Hg) concentrations in the soils of the North China plain, Loess Plateau, Changping District. Haiyuan fault zone, and north Beiluntai (BLT) fault at the edge of south Tianshan. The factors affecting the soil gas Hg concentration, such as the sampler type, test hole depth, soil characteristics, fault characteristics, and the mechanisms of their influence are discussed in terms of a gas diffusion equation. The results show that (1) the soil gas Hg concentration is affected mainly by the time lapse between the hole drilling and measurement, test hole depth and sampler shape; (2) the measured soil gas Hg concentration agrees well with the gas diffusion equation analytical solution, and the curve shape is closely related to the degree of Hg enrichment in the soil and the soil density; and (3) the soil gas concentration in the fracture zone is largely affected by the rock type, tectonics, the fault slip rate, the degree of fault locking, the development degree of fractures between the hanging wall and footwall, and the degree of fracture locking because these factors can alter the Hg upward transport channels and degree of surface enrichment. The effects of these factors on the diffusion coefficient in shallow soil layers are insignificant. The diffusion coefficient D depends on the particle size, density and porosity of the soil materials. [ABSTRACT FROM AUTHOR]

Background: Estimated physiologic requirements (PRs) for zinc increase in late pregnancy and early lactation, but the effect on dietary zinc requirements is uncertain.Objective: The aim of this study was to determine changes in daily fractional absorbed zinc and total absorbed zinc (TAZ) from ad libitum diets of differing phytate contents in relation to physiologic zinc requirements during pregnancy and lactation.Methods: This was a prospective observational study of zinc absorption at 8 (phase 1) and 34 (phase 2) wk of gestation and 2 (phase 3) and 6 (phase 4) mo of lactation. Participants were indigenous Guatemalan women of childbearing age whose major food staple was maize and who had been randomly assigned in a larger study to either of 2 ad libitum feeding groups: low-phytate maize (LP; 1.6 mg/g; n = 14) or control maize (C; 7.1 mg/g; n = 8). Total dietary zinc (milligrams per day, TDZ) and phytate (milligrams per day) were determined from duplicate diets and fractional absorption (FAZ) by dual isotope ratio technique (TAZ = TDZ × FAZ). All variables were examined longitudinally and by group and compared with PRs. TAZ values at later phases were compared with phase 1. Measured TAZ was compared with predicted TAZ for nonpregnant, nonlactating (NPNL) women.Results: TAZ was greater in the LP group than in the C group at all phases. All variables increased from phase 1 to phases 2 and 3 and declined at phase 4. TAZ increased by 1.25 mg/d (P = 0.045) in the C group and by 0.81 mg/d (P = 0.058) in the LP group at phase 2. At phase 3, the increases were 2.66 mg/d (P = 0.002) in the C group and 2.28 mg/d (P = 0.0004) in the LP group, compared with a 1.37-mg/d increase in PR. Measured TAZ was greater than predicted values in phases 2-4.Conclusions: Upregulation of zinc absorption in late pregnancy and early lactation matches increases in PRs of pregnant and lactating women, regardless of dietary phytate, which has implications for dietary zinc requirements of pregnant and lactating women. [ABSTRACT FROM AUTHOR]

Background: Zinc and copper have many physiologic functions and little or no functional storage capability, so persistent losses of either element present health concerns, especially during extended-duration space missions.Objectives: We evaluated the effects of short-term bed rest (BR), a spaceflight analog, on copper and zinc metabolism to better understand the role of these nutrients in human adaptation to (simulated) spaceflight. We also investigated the effect of artificial gravity on copper and zinc homeostasis.Methods: Zinc and copper balances were studied in 15 men [mean ± SD age: 29 ± 3 y; body mass index (in kg/m2): 26.4 ± 2.2] before, during, and after 21 d of head-down tilt BR, during which 8 of the participants were subjected to artificial gravity (AG) by centrifugation for 1 h/d. Control subjects were transferred onto the centrifuge but were not exposed to centrifugation. The study was conducted in a metabolic ward; all urine and feces were collected. Data were analyzed by 2-factor repeated-measures ANOVA.Results: Urinary zinc excretion values for control and AG groups were 33% and 14%, respectively, higher during BR than before BR, and fecal zinc excretion values for control and AG groups were 36% and 19%, respectively, higher during BR, resulting in 67% and 82% lower net zinc balances for controls and AG, respectively (both P < 0.01), despite lower nutrient intake during BR. Fecal copper values for control and AG groups were 40% and 33%, respectively, higher during BR than before BR (P < 0.01 for both). Urinary copper did not change during BR, but a 19% increase was observed after BR compared with before BR in the AG group (P < 0.05).Conclusions: The increased fecal excretion of copper and zinc by men during BR suggests that their absorption of these minerals from the diet was reduced, secondary to the release of minerals from bone and muscle. These findings highlight the importance of determining dietary requirements for astronauts on space missions and ensuring provision and intake of all nutrients. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulation of [Cd(II)] along with nitrate ions and water in dodecane was carried out for different nitric acid concentrations. The extraction process using N,N,N’,N’-tetraoctyldiglycolamide (TODGA) and tributyl phosphate (TBP), in biphasic systems, is also simulated at three nitric acid concentrations. In the TBP-based system, the formation of a third phase was observed at 3 M nitric acid concentration. Cd(II) ions form reverse micelles-like clusters with TODGA as an extractant in dodecane. The mass percentage of TODGA in these clusters decreases with increase in the acid concentration while increasing the size of the aggregates at the same time. [ABSTRACT FROM PUBLISHER]

Herein we report that oxalate serves as a template in the formation of di-zinc macrocycles featuring bis(imino)pyridine chelating units linked by p -xylylene or m -xylylenes linkers. The resulting complexes were characterized by NMR spectroscopy, mass spectrometry, elemental analysis, and X-ray crystallography. NMR spectroscopy indicates highly symmetrical ( C 2v or D 2h ) structures of the macrocyclic complexes in solution. Solid-state structures, determined by X-ray crystallography (obtained only for the m -xylylene bridged macrocycles), revealed hexa-coordinate zinc centers with μ 2 -κ 2 ,κ 2 -bound oxalate, meridional NNN chelates, and an additional ligand (DMF or H 2 O) bound to zinc centers. Cyclic voltammetry demonstrates series of reductions associated with the redox-active bis(imino)pyridine chelates; no oxidation was observed up to 1 V. We have attempted to extract oxalate from the macrocycle using calcium bromide, ethylenediaminetetraacetic acid (EDTA), trimethyl silyl chloride (TMSCl), acetic acid, or hydrochloric acid (HCl). Of the above, EDTA, TMSCl, acetic acid, and HCl in ether failed to remove oxalate or to form a new isolable product, while calcium bromide transformed μ 2 -κ 2 ,κ 2 -bound oxalate into the μ 2 -κ 1 ,κ 2 -bound form. The addition of aqueous HCl enables observation of the oxalate-free complex by mass spectrometry as one of the major products. [ABSTRACT FROM AUTHOR]

Genomic regions responsible for accumulation of grain iron concentration (Fe), grain zinc concentration (Zn), grain protein content (PC) and thousand kernel weight (TKW) were investigated in 286 recombinant inbred lines (RILs) derived from a cross between an old Indian wheat variety WH542 and a synthetic derivative (Triticum dicoccon PI94624/Aegilops squarrosa [409]//BCN). RILs were grown in six environments and evaluated for Fe, Zn, PC, and TKW. The population showed the continuous distribution for all the four traits, that for pooled Fe and PC was near normal, whereas, for pooled Zn, RILs exhibited positively skewed distribution. A genetic map spanning 2155.3cM was constructed using microsatellite markers covering the 21 chromosomes and used for QTL analysis. 16 quantitative trait loci (QTL) were identified in this study. Four QTLs (QGFe.iari-2A, QGFe.iari-5A, QGFe.iari-7A and QGFe.iari-7B) for Fe, five QTLs (QGZn.iari-2A, QGZn.iari-4A, QGZn.iari-5A, QGZn.iari-7A and QGZn.iari-7B) for Zn, two QTLs (QGpc.iari-2A and QGpc.iari-3A) for PC, and five QTLs (QTkw.iari-1A, QTkw.iari-2A, QTkw.iari-2B, QTkw.iari-5B and QTkw.iari-7A) for TKW were identified. The QTLs together explained 20.0%, 32.0%, 24.1% and 32.3% phenotypic variation, respectively, for Fe, Zn, PC and TKW. QGpc.iari-2A was consistently expressed in all the six environments, whereas, QGFe.iari-7B and QGZn.iari-2A were identified in two environments each apart from pooled mean. QTkw.iari-2A and QTkw.iari-7A, respectively, were identified in four and three environments apart from pooled mean. A common region in the interval of Xgwm359-Xwmc407 on chromosome 2A was associated with Fe, Zn, and PC. One more QTL for TKW was identified on chromosome 2A but in a different chromosomal region (Xgwm382-Xgwm359). Two more regions on 5A (Xgwm126-Xgwm595) and 7A (Xbarc49-Xwmc525) were found to be associated with both Fe and Zn. A QTL for TKW was identified (Xwmc525-Xbarc222) in a different chromosomal region on the same chromosome (7A). This reflects at least a partly common genetic basis for the four traits. It is concluded that fine mapping of the regions of the three chromosomes of A genome involved in determining the accumulation of Fe, Zn, PC, and TKW in this mapping population may be rewarding. [ABSTRACT FROM AUTHOR]

The absolute concentration of Zn in human fingernail clippings was determined ex vivo using 1064 nm laser-induced breakdown spectroscopy and confirmed by speciated isotope dilution mass spectrometry. A nail testing protocol that sampled across the nail (perpendicular to the direction of growth) was developed and validated by scanning electron microscopy energy-dispersive X-ray spectrometry. Using this protocol, a partial least squares (PLS) regression model predicted the Zn concentration in the fingernails of five people to within an average of 7 ppm. The variation in the Zn concentration with depth into the nail determined by laser-induced breakdown spectroscopy was studied and showed no systematic variation for up to 15 subsequent laser pulses in one location. The effects of nail hydration (dehydrated and over-hydrated) and nail surface roughness were investigated to explain an anomalously large scatter observed in the measurements. This scatter was attributed to the layered nature and fibrous structure of the fingernails, which resulted in non-uniform ablation as determined by scanning electron microscopy. This work demonstrates that a protocol consisting of low pulse energy (<10 mJ) 1064 nm laser pulses incident on human fingernail clippings in an Ar environment can produce quantifiable Zn emission in the laser-induced plasma and that the measured Zn intensity can be used to accurately predict the Zn concentration in human fingernails. [ABSTRACT FROM AUTHOR]

Cavities and adsorption sites in adsorption materials can be easily blocked in complex media containing solid particles and floccules, which limit the applicability of these materials. This study demonstrates the synthesis of cadmium(II) ion-imprinted polymers (Cd-IIPs) and nonion-imprinted polymers (NIPs) via reversible addition-fragmentation chain transfer precipitation polymerization (RAFTPP). Microspheres of IIPs and NIPs were modified by grafting bicomponent polymer brushes with different ratios of a hydrophilic component, hydroxyethyl methacrylate (HEMA), and a rigid component, styrene. The maximum adsorption capacities of the IIPs and NIPs in pure water are 65.5 and 24.5 mg/g, respectively. Specifically, the 9:1-IIP exhibits excellent antiblockage and anti-interference performance, with an adsorption capacity considerably higher than those of IIPs in simulated wastewater including SiO2 solid particles and floccules. This higher performance suggests that the 9:1-IIP has the rigidity to resist chaff interference from different aqueous media and also possesses good water-compatibility. The 9:1-IIP has a high recognition ability and high selectivity (α > 5.9) to Cd(II) although the surface is grafted with bicomponent polymer brushes. Furthermore, the steric hindrance due to the styrene on the bicomponent polymer brushes, in addition to van der Waals interactions with the interfering chaff, was confirmed to result in a "broom effect". The developed sorbents demonstrate the expected adsorption capacities when applied to environmental samples from factories, which indicate that IIP microspheres grafted with polymer brushes have significant potential for application in complex wastewater treatment. [ABSTRACT FROM AUTHOR]

Objective There is evidence that the mineral zinc is involved in the apoptotic cell death of various carcinoma cells. In this study, we aim to determine whether zinc in the form of CIZAR induces apoptosis in cervical carcinoma cells by increasing intracellular zinc concentration. Study design CaSki and HeLa cervical carcinoma cells and HPV-16 DNA-transformed keratinocyte (CRL2404) were treated with different concentrations of CIZAR. The cell viability test was carried out, the intracellular level of zinc was determined, and apoptosis was confirmed by flow cytometry after propidium iodide (PI) staining and fluorescence microscopy under DAPI staining. The expression of cell-cycle regulators was analyzed by Western blot, including the knock down of p53 and expression of HPV E6 and E7 genes by RT-PCR. Results Intracellular zinc accumulation induced the down-regulation of E6/E7 proteins through targeting of the specific transcriptional factors in the upstream regulatory region. p53 was induced after CIZAR treatment and p53-dependent apoptosis did not occur after knock down by p53 siRNA. In cervical carcinoma cells, regardless of HPV-infection, CIZAR induces apoptosis by the activation of the p53-independent pathways through the up-regulation of p21waf1, the down-regulation of c-Myc, and by decreasing the Bcl-2/Bax ratio. Conclusions CIZAR induces apoptosis not only through the restoration of p53/Rb-dependent pathways in HPV-positive cells, but also through the activation of p53/Rb-independent pathways and the mitochondrial death-signal pathway in cervical carcinoma cells regardless of HPV-infection. [ABSTRACT FROM AUTHOR]

Fourhorn sculpins ( Myoxocephalus quadricornis ) and shorthorn sculpins ( Myoxocephalus scorpius ) have been considered suitable local bioindicators for environmental monitoring studies in the Arctic. Because these species share many characteristics, data from the two species have previously been pooled when assessing marine metal contamination. A chemical and histological study was conducted on fourhorn and shorthorn sculpins collected around a contaminated lead-zinc mine at East Greenland to investigate whether there were any differences in the residues of metals, histopathology and parasites in liver and gills between the two sculpin species. The results demonstrated that concentrations of copper (Cu), zinc (Zn), mercury (Hg) and lead (Pb) were significantly higher in the fourhorn sculpins ( p <0.001) while there were no significant differences for arsenic (As) or cadmium (Cd). Furthermore, density of blood vessel fibrosis ( p =0.028), prevalence and density of chondroplasia ( p =0.002 and p =0.005, respectively), number of mucin-containing mucous cells ( p <0.001) and chloride cells ( p <0.001) and mean intensity of colonial Peritricha ( p <0.001) were significantly higher in fourhorn sculpin. Based on these results we suggest that pooling the two species when conducting environmental assessments is not recommended as it can lead to incorrect conclusions. We propose that a larger study investigating the biological effects of zinc-lead mining in Greenland is needed. [ABSTRACT FROM AUTHOR]

The morphology and dimensions of bioactive materials are essential attributes to promote tissue culture. Bioactive materials with nanofibrous structure have excellent potential to be used as bone-defect fillers, since they mimic the collagen in the extracellular matrix. On the other hand, bioactive glasses with applications in regenerative medicine may present antibacterial properties, which depend on glass composition, concentration and the microorganisms tested. Likewise, their morphology may influence their antibacterial activity too. In the present work, the laser-spinning technique was used to produce bioactive glass nanofibers of two different compositions: 45S5 Bioglass® and ICIE16M, bioactive glass doped with zinc and strontium. Their antibacterial activity against Staphylococcus aureus was tested by culturing them in dynamic conditions. Bacterial growth index profiles during the first days of experiment can be explained by the variations in the pH values of the media. The bactericidal effect of the doped nanofibers at longer times is justified by the release of zinc and strontium ions. Cytotoxicity was analyzed by means of cell viability tests performed with BALB/3T3 cell line. [ABSTRACT FROM AUTHOR]

BACKGROUND In the present work, Hg ( II) is considered as one of the most dangerous elements being released excessively into the environment from various sources. Therefore, the aim of this study is the removal of Hg ( II) from wastewater effluent by synthesizing a magnetic chitosan modified with glutaraldehyde ( MCS-GA) as an adsorbent. The composite structure was characterized using SEM/ EDAX, FTIR, and XRD techniques. The adsorbent was tested by a batch system to determine the optimum conditions for removing Hg ( II) under real conditions. RESULTS The results showed that 0.5% GA effectively enhanced the removal efficiency. The maximum adsorption capacity of MCS-GA was 96 mg g−1 at pH 5.0 and 25 °C. The adsorption isotherm data obeyed the Langmuir model ( R2>0.981) and pseudo-second-order ( R2>0.996) kinetic models. It was also found that Hg ( II) adsorption on MCS-GA is inherently exothermic and occurs spontaneously. The reusability of MCS-GA was approved over 12 sequential cycles of adsorption-desorption. ANOVA analysis showed that the contact time has a synergistic effect on Hg ( II) removal, whereas pH and initial concentration have antagonistic effects. CONCLUSION Overall, the synthesized adsorbent was able to remove Hg ( II) efficiently under both experimental and real conditions. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Commercial extractants LIX 54 -100, LIX 84 I and TOA were used to recover zinc(II) from ammonia solutions. The effect of extractant and ammonia concentration, contact time and reextraction were studied. It was found that extraction of zinc depended on the ammonia, ammonium sulphate and extractant concentration but did not depend on the contact time. The McCabe-Thiele distribution isotherm for LIX 54-100 showed that 95% of zinc(II) ions can be recovered in four stages of extraction. Reextraction of Zn(II) ions from the loaded organic phase showed that the metal can be removed almost completely using sulphuric acid. [ABSTRACT FROM AUTHOR]