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Proposed is an ultra-low-profile loop antenna backed by an electromagnetic bandgap (EBG) surface reflector, where the EBG surface can effectively exhibit the property of a perfect magnetic conductor (PMC) inside a deliberately designed bandwidth. It is shown that, assisted by the effective PMC bandwidth, while the proposed antenna is with a 0.07-λ spacing between the loops and the EBG reflector, its axial ratio (AR) and voltage standing wave ratio (VSWR) performances are significantly improved. Experimental measurements show that the prototype antenna has a 3 dB AR bandwidth of 17% with an input VSWR less than 1.6. The proposed approach can find a wide range of low-profile circularly polarised (CP) antenna applications.

Glycosylated hemoglobin (HbA1c) identifies the average plasma glucose concentration over 120 days. HbA1c test measurements can lead to false outcomes in patients with inherited hemoglobin variants as hemoglobin S, which is prevalent in the Middle Eastern population. Our aim was to evaluate four different methods for measuring the blood HbA1c levels in diabetic patients with sickle cell anemia (SCA) and sickle cell trait (SCT). Blood samples were collected in EDTA tubes from 38 diabetic patients with either SCA or SCT. HbA1c levels were measured on all samples at three different local hospitals using three different analyzers: the Cobas Integra700 (Roche, SZ), the Dimension RXL (Siemens, USA), and the DCA2000 (Siemens, USA). All methods were compared to the standard HPLC method Variant (Bio-Rad, USA). There was a good correlation (R2) between HbA1c levels measured by the HPLC Variant II and immunoassay analyzers and between the immunoassay analyzers themselves in SCT, but not in SCA, patients. However, an excellent correlation was observed in the SCA group between the Dimension RXL and Cobas Integra analyzers (R2 = 0.9918). Significant differences were observed in all the three immunoassay methods compared to the Variant HPLC (P <0.00001) and between the DCA2000+ and the Dimension RXL (P = 0.0144), as well as between the DCA2000+ and the Cobas Integra (P = 0.0247). We concluded that while HbA1c levels were undetected by some methods, other methods were able to measure HgbA1c with a high degree of accuracy. Therefore, we recommend that any affected HbA1c samples should be measured by two different methods.

Global patterns of human DNA sequence variation (haplotypes) defined by common single nucleotide polymorphisms (SNPs) have important implications for identifying disease associations and human traits. We have used high-density oligonucleotide arrays, in combination with somatic cell genetics, to identify a large fraction of all common human chromosome 21 SNPs and to directly observe the haplotype structure defined by these SNPs. This structure reveals blocks of limited haplotype diversity in which more than 80% of a global human sample can typically be characterized by only three common haplotypes.

Vitamin D binding protein (DBP) is a major carrier protein for the vitamin D metabolites, but may also play an important role in osteoclast differentiation. Polymorphisms of the DBP gene have been reported, including (TAAA)^sub n^-Alu repeat polymorphisms downstream of intron 8. We have examined the relationship between polymorphisms of the DBP gene and bone mineral density (BMD) and vertebral fractures in a group of 26 men with vertebral fractures but no underlying secondary cause of osteoporosis (median age 64, ages 27-72 years) and 21 male control subjects (median age 65, ages 40-77 years). There was no apparent effect of DBP phenotype on BMD, but there was a relationship between certain genotypes of (TAAA)^sub n^-Alu repeats and reduced BMD and vertebral fracture. Lumbar spine and femoral neck BMD were significantly lower in men with 10/8 genotype than 10/10 genotype (P < 0.05). Furthermore, the predominant genotype in men with vertebral fractures was 10/8, whereas the most common genotype in control subjects was 10/10 (odds ratio 56; 95% confidence interval 7-445). Plasma DBP was higher in men with 10/8 genotype than those with 10/10 genotype (P < 0.05), and patients with vertebral fractures were found to have higher levels than control subjects (P < 0.0005). Although our study is small because of the relative rarity of idiopathic osteoporosis in men, the results suggest that (TAAA)^sub n^-Alu polymorphism may have an important effect on plasma levels of DBP, bone density and fracture risk in men.[PUBLICATION ABSTRACT]

Vitamin D binding protein (DBP) is a major carrier protein for the vitamin D metabolites, but may also play an important role in osteoclast differentiation. Polymorphisms of the DBP gene have been reported, including (TAAA)(n)-Alu repeat polymorphisms downstream of intron 8. We have examined the relationship between polymorphisms of the DBP gene and bone mineral density (BMD) and vertebral fractures in a group of 26 men with vertebral fractures but no underlying secondary cause of osteoporosis (median age 64, ages 27-72 years) and 21 male control subjects (median age 65, ages 40-77 years). There was no apparent effect of DBP phenotype on BMD, but there was a relationship between certain genotypes of (TAAA)(n)-Alu repeats and reduced BMD and vertebral fracture. Lumbar spine and femoral neck BMD were significantly lower in men with 10/8 genotype than 10/10 genotype (P < 0.05). Furthermore, the predominant genotype in men with vertebral fractures was 10/8, whereas the most common genotype in control subjects was 10/10 (odds ratio 56; 95% confidence interval 7-445). Plasma DBP was higher in men with 10/8 genotype than those with 10/10 genotype (P < 0.05), and patients with vertebral fractures were found to have higher levels than control subjects (P < 0.0005). Although our study is small because of the relative rarity of idiopathic osteoporosis in men, the results suggest that (TAAA)(n)-Alu polymorphism may have an important effect on plasma levels of DBP, bone density and fracture risk in men.

Proposed is an ultra-low-profile loop antenna backed by an electromagnetic bandgap (EBG) surface reflector, where the EBG surface can effectively exhibit the property of a perfect magnetic conductor (PMC) inside a deliberately designed bandwidth. It is shown that, assisted by the effective PMC bandwidth while the proposed antenna is with a 0.07-λ spacing between the loops and the EBG reflector; its axial ratio (AR) and voltage standing wave ratio (VSWR) performances are significantly improved. Experimental measurements show that the prototype antenna has a 3 dB AR bandwidth of 17% with an input VSWR less than 1.6. The proposed approach can find a wide range of low-profile circularly polarised (CP) antenna applications.

Molten salts at intermediate temperatures enable efficient carbonate-promoted carboxylation of very weakly acidic C–H bonds, revealing a new way to transform inedible biomass and carbon dioxide into valuable feedstock chemicals. CO 2 as a chemical feedstock The idea that the greenhouse gas carbon dioxide might be used as a source of feedstock chemicals is attractive but usually impractical — although it reacts readily with carbon-centred nucleophiles, generating the nucleophiles requires a high energy input. But now, inspired by the RuBisCO enzyme which catalyses carbon fixation in plants, Aanindeeta Banerjee et al . demonstrate that molten salts containing alkali metals at intermediate temperatures enable efficient carbonate-promoted carboxylation of very weakly acidic C–H bonds. The potential of this chemistry was illustrated by converting 2-furoic acid (readily made from inedible biomass) into the useful bio-based feedstock furan-2,5-dicarboxylic acid. Using carbon dioxide (CO 2 ) as a feedstock for commodity synthesis is an attractive means of reducing greenhouse gas emissions and a possible stepping-stone towards renewable synthetic fuels 1 , 2 . A major impediment to synthesizing compounds from CO 2 is the difficulty of forming carbon–carbon (C–C) bonds efficiently: although CO 2 reacts readily with carbon-centred nucleophiles, generating these intermediates requires high-energy reagents (such as highly reducing metals or strong organic bases), carbon–heteroatom bonds or relatively acidic carbon–hydrogen (C–H) bonds 3 , 4 , 5 . These requirements negate the environmental benefit of using CO 2 as a substrate and limit the chemistry to low-volume targets. Here we show that intermediate-temperature (200 to 350 degrees Celsius) molten salts containing caesium or potassium cations enable carbonate ions (CO 3 2– ) to deprotonate very weakly acidic C–H bonds (p K a  > 40), generating carbon-centred nucleophiles that react with CO 2 to form carboxylates. To illustrate a potential application, we use C–H carboxylation followed by protonation to convert 2-furoic acid into furan-2,5-dicarboxylic acid (FDCA)—a highly desirable bio-based feedstock 6 with numerous applications, including the synthesis of polyethylene furandicarboxylate (PEF), which is a potential large-scale substitute for petroleum-derived polyethylene terephthalate (PET) 7 , 8 . Since 2-furoic acid can readily be made from lignocellulose 9 , CO 3 2– -promoted C–H carboxylation thus reveals a way to transform inedible biomass and CO 2 into a valuable feedstock chemical. Our results provide a new strategy for using CO 2 in the synthesis of multi-carbon compounds.

Understanding how the bulk structure of a material affects catalysis on its surface is critical to the development of actionable catalyst design principles. Bulk defects have been shown to affect electrocatalytic materials that are important for energy conversion systems, but the structural origins of these effects have not been fully elucidated. Here we use a combination of high-resolution scanning electrochemical cell microscopy and electron backscatter diffraction to visualize the potential-dependent electrocatalytic carbon dioxide ( C O 2 ) electroreduction and hydrogen ( H 2 ) evolution activity on Au electrodes and probe the effects of bulk defects. Comparing colocated activity maps and videos to the underlying microstructure and lattice deformation supports a model in which CO 2 electroreduction is selectively enhanced by surface-terminating dislocations, which can accumulate at grain boundaries and slip bands. Our results suggest that the deliberate introduction of dislocations into materials is a promising strategy for improving catalytic properties. Although bulk defects can influence the performance of electrocatalysts used for energy conversion, their structural origins are still unclear. The effects of bulk defects on CO 2 electroreduction and H 2 evolution activity on Au electrodes are now elucidated.

Do you get palpitations when you have to go on a boat ride? Does your heart beat in dread when you have to take a swim in the ocean? Does a picnic under a waterfall feel like a nightmare?

My first thought to the terror attacks in my city was, \"I go to those places, and I could have been there!\" My...