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"Metal ions in the brain are a necessity as well as a poison. The presence of metal ions in the active sites of biological catalysts or metalloproteins and in the biological functioning of nucleic acids is very well documented and they are required for brain activity. On the other hand, metals are very effective in generating oxidative stress. This effect does not only play a role in immunology but also is the root of practically all neurodegenerative disorders by inducing disease via the death of neurons. Managing metal ions in the brain could therefore be an important strategy in the search for therapeutic agents used in the treatment of neurodegenerative diseases. This new title gives an overview to key topics in the area of metal ions in the brain. It focuses on the role of metal ions in neurological systems by describing their advantageous functions as well as their poisonous features. It is therefore of interest for scientists in biochemistry and biophysics, physiology, toxicology as well as for physicians focused on this topic."

"The volume concentrates on modern developments encompassing topics in the wide range from G-quadruplexes via DNAzymes, catalysis at the DNA scaffold, and metal-mediated base pairs to peptide nucleic acids (PNAs) being thus of relevance, e.g., for chemistry and nanotechnology but also for molecular biology and (genetic) diagnostics."

"Fully revised for the latest building codes and industry trends, Metal Building Systems, Third Edition, explains how to select, specify, and design preengineered buildings with confidence"

"The explosive sensitivity upon the formation of supramolecular interaction between the nitro group of 3-nitro-1,2,4-triazol-5-one (NTO) and metal ions (Mn+ = Li+, Na+, Be2+ and Mg2+) has been investigated using Density FunctionalTheory at B3LYP/6-311++G** level of theory. The bond dissociation energy (BDE) of the C1?N6 trigger bond hasalso been discussed for the NTO monomer and the corresponding complexes. The interaction and bond dissociationenergy of the C6?N7 trigger bond follow the order of NTO-Be2+ > NTO-Mg2+ > NTO-Li+ > NTO-Na+ > NTOmonomer. The enhancement of the trigger bond dissociation energy in comparison with the NTO monomer correlateswell with the complex interaction energies, trigger bond length, and charge transfer. The analyses of electron densityshifts have shown that the electron density of the nitro group shifts toward the C1?N6 trigger bond upon the formationof the supramolecular interaction. As result, the trigger bond is strengthened and the sensitivity of NTO is reduced.Some of the calculated results agree with the experimental values.Sensitivitas Peledak Akibat Pembentukan Kompleks 3-Nitro-1,2,4-Triazol-5-One dan Ion Logam berdasarkanTeori Fungsional Kerapatan. Sensitivitas peledak yang terbentuk dari interaksi supramolekuler senyawa 3-nitro-1,2,4-triazol-5-one (NTO) dan ion logam (Mn+ = Li+, Na+, Be2+ and Mg2+) telah dipelajari menggunakan TeoriFungsional Kerapatan pada tingkatan teori B3LYP/6-311++G**. Energi pemutusan ikatan pada ikatan pemicu ledakan(C1-C6) juga telah dipelajari untuk monomer NTO dan senyawa kompleksnya. Energi ikat dan energi pemutusan ikatanmengikuti urutan: NTO-Be2+ > NTO-Mg2+ > NTO-Li+ > NTO-Na+ > monomer NTO. Peningkatan energi pemutusanikatan berbanding lurus dengan energi ikat, panjang ikatan pemicu ledakan dan transfer muatan. Analisis perubahankerapatan elektron menunjukkan bahwa kerapatan elektron gugus nitro berpindah pada ikatan C1-N6 ketika kompleksterbentuk. Hal ini menyebabkan ikatan pemicu ledakan menjadi semakin kuat sehingga sensitivitas NTO menjadiberkurang. Hasil kajian teoritis ini sesuai dengan hasil kajian eksperiemen."

"Residu pestisida organofosfat di alam sangat berbahaya bagi manusia karena dapat menginhibisi enzim asetilkolinesterase (AChE) di alam neurotransmitter otak. Pada penelitian ini dikembangkan metode pengukuran pestisida dengan cara memonitor aktivitas AChE melalui pembentukan tiokolin hasil hidrolisis enzimatik asetiltiokolin iodida (ACTI). Tiokolin yang terbentuk dapat dioksidasi secara elektrokimia pada elektroda boron-doped diamond (BDD) sehingga digunakan metode elektrokimia dengan BDD sebagai elektroda kerja. BDD dipreparasi dengan Microwave Plasma Assisted Chemical Vapor Deposition. Karakterisasi dengan SEM menunjukkan ukuran partikel diamond sebesar 3 μm. Sebelum digunakan BDD dioksidasi secara elektrokimia agar memiliki terminasi oksigen. Hasil XPS menunjukkan kenaikan O/C ratio dari 0,09 ke 0,3 setelah proses oksidasi. Waktu kontak optimum ACTI dengan AChE pada pengukuran deteksi tiokolin adalah 25 menit dengan pH optimum 7,6. Tiokolin teroksidasi pada BDD di bawah pengaruh arus difusi dengan koefisien difusi1,37x10-10 m2/s. Waktu inhibisi optimum chlorpyrifos terhadap AChE adalah 10 menit. Pengukuran dilakukan dengan 2 cara, yaitu menggunakan AChE bebas dan AChE terimobilisasi pada magnetic beads. Kurva kalibrasi linier pada pada rentang konsentrasi 0,1-1x10-5 mM dapat dicapai pada kedua sistem. Namun linieritas dan limit deteksi yang lebih baik dicapai pada sistem dengan AChE bebas. Uji interferensi dilakukan dengan ion logam Fe(II) dan Mn(II) yang ditambahkan pada chlorpyrifos. Hasil pengukuran menunjukkan kedua sistem tidak tahan terhadap interferensi ion logam. Sehingga untuk mendapatkan deteksi chlorpyrifos yang baik diharapkan interferensi ion logam kurang dari 1 ppb.

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Residue of organophosphorus pesticide is very dangerous to humans due to its ability to inhibit acetylcholinesterase (AChE) enzyme in neurotransmitter of human brain.In this research, the detection of organophosphate pesticide is developed by monitoring AChE activity through the formation of thiocholine as the result of enzymatic hydrolysis of acetilthiocholine iodides (ACTI) by AChE. Since thiocholine can be electrochemically oxidized at boron-doped diamond (BDD) electrode, an electrochemical method with BDD as the working electrode was utilized. The BDD was prepared using a Chemical Microwave Plasma Assisted Vapor Deposition.Characterization by using SEM showed diamond particles with thediameter size of 3 μm. Prior to use, the BDD was electrochemically oxidized to perform oxygen termination. Characterization by using XPS showed the increasing of O/C ratio from 0,09 to 0,3. An optimum contact time between ACTI and AChE of 25 min with pH 7,6 was obtained. Thiocholine was oxidized at BDD under diffusion control with diffusion coefficient of 1,37x10-10 m2/s. The optimum inhibition time of chlorpyrifos to AChE was 10 minutes. The measurements were performed using 2 types of systems, including free AChE and AChE-immobilized at magnetic beads. Linear calibration curves in the concentration range of 0,1-1x10-5mMchlorpyrifoswereobtained using both systems. However, better linearity and limit of detection was achieved using freeAChE system. Interference was examined using Fe2+ and Mn2+ in chlorpyrifos solution. Both systems showed no resistant against the interference of metal ions. Therefore, for better detection ofchlorpyrifos, less than 1 ppb of metal intereference ions in the system is recommended."

"This paper discusses the preparation, characterization, and the evaluation of adsorption properties of resin poly-tetra-p-allylcalix[4]arene tetra acetic acid from the p-t-butylphenol. The synthesized resins were applied as an adsorbent for Cr(III) and Pb(II) metal ions. The adsorption was conducted in a batch system by investigating the effects of acidity (pH), contact time and initial concentration of a heavy metal solution. The adsorption of Cr(III) and Pb(II) metal ions on the resin had the optimum pH rating in region of 4–6 and reached the equilibrium condition in 40 minutes. The adsorption of Cr(III) and Pb(II) metal ions on the resin follows the Langmuir isothermal pattern with the linearity constant (R2 ) of Cr(III) and Pb(II) adsorption, whose results were 0.9640 and 0.9716, respectively. The adsorption capacity of Cr(III) and Pb(II) metal ions is 323.0 µmole/g and 33.4 µmole/g, while the adsorption energy is 30.4 kJ/mole and 39.7 kJ/mole, respectively. Most parameters in batch systems confirm that resin is a good adsorbent for Cr(III) and Pb(II), though Cr(III) adsorption was more favorable than that of Pb(II). The outstanding adsorption abilities for Cr(III) and Pb(II) metal ions have exhibited good prospects for disposal application of polluted water and environmental protection."