A gamma-ray scattering technique for estimation of density and moisture content of wood

A densitometer system, operating in a non-destructive and non-invasive way, is presented to investigate the density and moisture variation in wood samples of Pinus roxburghii (known as chir pine). The inherent ability of Compton scattering can ascertain quantitative information of electron density of the target material. A well collimated beam of 662?keV gamma rays from ¹³⁷Cs radioactive source has been used to extract the information of density from interior of sample by recording scattered spectra with NaI(Tl) scintillation detector. An inverse matrix approach for unfolding of observed pulse-height distribution to a true photon spectrum is used, by choosing bin mesh (E^1/2) of 0.025 (MeV)^1/2, for the measurements of scattered spectra. The regression lines, obtained from data of scattered spectra, provide the density and moisture content of selected wood sample. The adjusted R² value 0.984 for fitted curve, justifies the linear dependence of scattered intensity upon wood density. Also, Compton scatter measurements results that the technique is less sensitive beyond wood thickness of ～110?mm due to overlying scatter components in the measured spectrum.     

Endogenous high‐performance liquid chromatography/tandem mass spectrometry interferences and the case of perfluorohexane sulfonate (PFHxS) in human serum; are we overestimating exposure?

Perfluorinated acids have received increasing scientific attention due to their widespread global distribution, environmental persistence and bioaccumulation in wildlife and humans. For perfluorohexane sulfonate (PFHxS, C₆F₁₃SO, m/z 399), all existing human data have been generated using high‐performance liquid chromatography (HPLC) and its most sensitive tandem mass spectrometric (MS/MS) transitions (m/z 399/80 [SO₃]^? or m/z 399/99 [SO₃F]^?), but this may be problematic because of co‐eluting endogenous steroid sulfates that share common fragmentation pathways. We examined the magnitude of over‐reporting for PFHxS in pregnant women (n = 29), and in pooled serum of males, non‐pregnant and pregnant females (n = 3, 100 samples per pool), by comparing m/z 399/80 and 399/99 data with an interference‐free transition, m/z 399/119. PFHxS concentrations in pregnant women determined using m/z 399/80 and 399/99 (p < 0.05), but not m/z 399/119, were positively correlated to the response of the steroid sulfates. This led to an average overestimation of PFHxS by 1.5‐ and 4.7‐fold, using m/z 399/80 and 399/99, respectively, and validated the use of m/z 399/119 for the first time. The interferences were a problem in all human serum samples, and analysis of pooled serum revealed statistically significant over‐reporting by m/z 399/80 and 399/99 for pregnant women > non‐pregnant women > men. The magnitude of over‐reporting here represents a worst‐case scenario, but the extent to which the published literature values are biased is unknown due to limited details of methods in existing reports. Instead of using the less sensitive m/z 399/119 transition, we showed that an alternative selection of column and mobile phase can allow for sufficient chromatographic separation of the interferences. In conclusion, it was shown that routine analytical methods are prone to systematically overestimating PFHxS concentrations in serum of men or women, but that this can be avoided by alternative chromatographic steps or MS/MS transitions. Copyright © 2009 John Wiley & Sons, Ltd.     

Experimental realization of an on-chip all-optical analogue to electromagnetically induced transparency

We provide the first experimental observation of structure tuning of the electromagnetically induced transparency-like spectrum in integrated on-chip optical resonator systems. The system consists of coupled silicon ring resonators with 10 microm diameter on silicon, where the coherent interference between the two coupled resonators is tuned. We measured a transparency-resonance mode with a quality factor of 11,800.     

Growth of InAsSb/InAs MQWs on GaSb for mid-IR photodetector applications

We report the OMVPE growth and characterization of InAsSb/InAs strain balanced multiple quantum wells lattice-matched to GaSb substrates for potential application as mid-infrared detectors for wavelengths beyond 4 μm$\mathrm{\mu }\mathrm{m}$. Detailed transmission electron microscopy measurements were performed to evaluate the degree of Ga and Sb intermixing at the GaSb/InAsSb and InAs/InAsSb interfaces. Photoluminescence emission up to 5 μm$\mathrm{\mu }\mathrm{m}$ was observed for superlattice structures with only 15% antimony. The dependence of PL on wavelength is red shifted compared to expectations based on type I band alignment.     

Intrahepatic arterioportal fistula: gadolinium-enhanced 3D magnetic resonance angiography findings and angiographic embolization with steel coils

We describe a case of a 59-year-old patient with intrahepatic arterioportal fistula secondary to blunt trauma sustained by a motor vehicle accident 36 years earlier. The fistula was demonstrated 36 years after the accident in a clinical work-up for diarrhea of 1 month's duration, using contrast enhanced three-dimensional breath-hold MRA. A communication between the dilated portal vein and dilated hepatic artery was shown at the level of distal branches. After subsequent demonstration by conventional angiography, the fistula was embolized using steel coils. Following the therapeutic intervention, the patient's diarrhea ceased.     

Synthesis,Biological Evaluation,and Molecular Docking Studies of Some N‐thiazolyl Hydrazones and Indenopyrazolones

Two new series of N‐thiazolyl hydrazones ( 3a – h ) and indenopyrazolones ( 4a – h ) were synthesized by the reaction of various 2‐acyl‐(1H)‐indene‐1,3(2H)‐diones, thiosemicarbazide, and phenacyl bromide/substituted phenacyl bromides. The in vitro antimicrobial activity of these synthesized compounds was assayed against four bacteria, namely, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and two fungi, namely, Candida albicans and Aspergillus niger, by employing serial dilution method. Ciprofloxacin and fluconazole were used as antibacterial and antifungal reference drugs, respectively. Results of antimicrobial assay showed that the tested compounds have broad range of activity. The compounds 3h and 4a against C. albicans displayed more potency than fluconazole whereas 3b and 3c against B. subtilis showed activity comparable with ciprofloxacin. The synthesized indenopyrazolones ( 4a – h ) were evaluated for their in vitro antioxidant activity by 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging assay using ascorbic acid as reference. Compound 4b exhibited the highest 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging with IC₅₀ value 33.14 μg/mL. The observed results of antimicrobial activity were supported by molecular docking study performed to understand the binding interaction of hydrazones ( 3a – h ) and indenopyrazolones ( 4a – h ) with lanosterol 14α‐demethylase.     

Preparation of spherical and uniform-sized ferrite nanoparticles with diameters between 50 and 150 nm for biomedical applications

Spherical uniform-sized iron ferrite nanoparticles were synthesized by adding a disaccharide and seed ferrite crystals into an aqueous reaction solution. The average size range 50-150 nm was controlled by choosing one out of five disaccharides and by changing the amount of the seed crystals. The particles had a saturation magnetization and a crystalline structure which are similar to those of intermediate Fe₃O₄-γ-Fe₂O₃. When coated with citrate, the particles with nearly 100 nm diameter were stably suspended in water for 2 days. These novel particles will be utilized as magnetic carriers in biomedical applications.     

Chemistry of iron complexes—IV. Spectroscopic,magnetic and other properties of complexes of iron(II) iodide and iron(II) tetracarbonyl iodide with b

Bis(tertiaryphosphine/arsine oxides), Ph₂E(O) (CH₂)_nE(O)Ph₂ react with iron(II) iodide and iron(II) tetracarbonyliodide forming com     

Complexes of metal ions with phosphorus or arsenic containing ligands. III. Complexes of Mercury (II) halides with 1,2-ethylenebisdiphenylphosphine and 1,4-butylenebisdiphenylphosphine

Mercury(II) halides react with 1,2-ethylenebisdiphenylphosphine (DPE) and 1,4-butylenebisdiphenylphosphine (DPB) to give two types of complexes having the general formulae, [(diphos)HgX₂] and [(diphos)(HgX₂)₂]. The former seems to possess chain structure, while the latter has probably a bridged structure. In both the cases mercury(II) acquires sp³ tetrahedral configuration.     

Complexes of metallons with phosphorus or arsenic containing ligands. II. complexes ortho-carboxyphenyltertiaryarsines with mercury (II) halides

Ortho-carboxyphenyl-dimethylarsine (CPDMA), ortho-carboxpyhenyldiphenylarsine (CPDPA) and ortho-carboxyphenyldi(p-tolyl)arsine (CPDTA) react with mercury(II) halides to yield complexes having the formula HgX₂L where X is Cl, Br or I and L is ligand. In view of infrared spectral data these complexes have been classified into two classes: (a) those in which the carboxyl group of the ligand remains free (ligand being monodentate), and (b) those in which the ligand acts as a bidentate group. The complex Hg(Cl₂) · CPDPA is the only example of type (a) and has been assigned a dimeric halogen bridged structure. The remaining eight complexes are assumed to be monomeric. A tetrahedral structure is proposed for all the nine complexes.