41 research outputs found

    The morphometric anatomy and clinical importance of the radial artery

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    Background: The radial forearm flap (RFF), including the radial artery and venous components, is used for hand reconstruction surgery. Updating the knowledge of the vascular anatomy in the forearm and associated flaps, such as the RFF, is useful in bringing innovations into reconstructive surgery. This study aimed to describe the morphometric anatomy of the radial artery (RA) and the associated RFF in human cadavers. Materials and methods: A total of 16 forearms from 8 human cadavers were dissected. The group consisted of 5 men and 3 women with a mean age at death of 59.05 ± 14.06 years. The inclusion criteria consisted of no history of trauma or surgery; thus, only apparently normal cadavers were included. The measurement of the following parameters was performed on these human cadavers: the mean diameter of the RA, the length of the RA, the average diameter of the cephalic vein, the length of the pedicle of the flap, and the average area of the radial forearm flap. Results: In males, the mean diameter of the radial artery at the wrist was 2.58 ± 1.1 mm. In females, the mean diameter of the radial artery was 2.60 ± 0.99 mm, and the mean length of the radial artery was 20.55 ± 1.7 cm. The average diameter of the cephalic vein was 1.8 ± 0.8 mm. The length of the pedicle of the flap was 8.88 ± 1.6 cm. The average area of the radial forearm flap was 5 X 7 cm2. Conclusions: This study demonstrates the morphometric anatomy of the RA and lateral forearm radial artery flaps in human cadavers, which could be useful in improving the success rate during transradial coronary interventions and performing complex hand injuries

    Triglyceride Glucose Index as an Indicator of Cardiovascular Risk in Syrian Refugees

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    Ameerah Hasan Ibrahim,1 Alaa Mahmoud Hammad,1 Walid Al-Qerem,1 Hakam Alaqabani,1,2 F Scott Hall,3 Fawaz Alasmari4 1Department of Pharmacy, Faculty of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan; 2Strathclyde Institute of Pharmacy and Biomedical sciences, University of Strathclyde, Glasgow, UK; 3Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH, USA; 4Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi ArabiaCorrespondence: Alaa Mahmoud Hammad, Department of Pharmacy, Faculty of Pharmacy, Al-Zaytoonah University of Jordan, P.O. Box 130, Amman, 11733, Jordan, Tel +962-6-4291511, Fax +962-6-4291432, Email [email protected]: The triglyceride glucose (TyG) index is a quick and inexpensive approach to measure insulin resistance. The aim of this study was to evaluate the TyG index’s ability to predict cardiovascular risk and determine the TyG index cutoff values in Syrian refugees.Methods: A retrospective research study was conducted with 756 Syrian refugees. Data on demographics and clinical laboratory assessments were obtained from refugee’s files. The formula Ln [fasting triglycerides (mg/dL) × fasting plasma glucose (mg (dL)/2] was used to calculate the TyG index. The Framingham risk score was used to calculate ten-year cardiovascular risk. The TyG index cutoff point was determined using the receiver operating characteristic curve (ROC).Results: Included participants had a mean age of 56.76 ± 10.78 years and a mean body mass index (BMI) of 27.42 ± 4.03 kg/m2. 28.57% of the subjects were smokers, and the majority were female (56.75%). A significant moderate correlation was observed between TyG index and Framingham score (r = 0.428, p < 0.001). ROC curve analysis for TyG index and Framingham score showed an area under the curve (AUC) of 0.741 (95% CI = 0.691– 0.791; p < 0.001). The cutoff value of the TyG index to recognize intermediate/high risk Framingham risk score was 9.33, with a sensitivity of 64.3%, and specificity of 75.0%.Conclusion: Our findings determine that, given a TyG index cutoff value of 9.33, the TyG index has a predictive ability to assess ten-year cardiovascular risk by comparison to the Framingham risk score in a high-risk group of Syrian refugees and can be used as an independent indicator of cardiovascular risk.Keywords: TyG index, Framingham risk score, ROC, Syrian refugees, cardiovascular ris

    AlN overgrowth of nano-pillar-patterned sapphire with different offcut angle by metalorganic vapor phase epitaxy

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    We present overgrowth of nano-patterned sapphire with different offcut angles by metalorganic vapor phase epitaxy. Hexagonal arrays of nano-pillars were prepared via Displacement Talbot Lithography and dry-etching. 6.6 µm crack-free and fully coalesced AlN was grown on such substrates. Extended defect analysis comparing X-ray diffraction, electron channeling contrast imaging and selective defect etching revealed a threading dislocation density of about 109 cm−2. However, for c-plane sapphire offcut of 0.2° towards m direction the AlN surface shows step bunches with a height of 10 nm. The detrimental impact of these step bunches on subsequently grown AlGaN multi-quantum-wells is investigated by cathodoluminescence and transmission electron microscopy. By reducing the sapphire offcut to 0.1° the formation of step bunches is successfully suppressed. On top of such a sample an AlGaN-based UVC LED heterostructure is realized emitting at 265 nm and showing an emission power of 0.81 mW at 20 mA (corresponds to an external quantum efficiency of 0.86%)

    AlN overgrowth of nano-pillar-patterned sapphire with different offcut angle by metalorganic vapor phase epitaxy

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    We present overgrowth of nano-patterned sapphire with different offcut angles by metalorganic vapor phase epitaxy. Hexagonal arrays of nano-pillars were prepared via Displacement Talbot Lithography and dry-etching. 6.6 µm crack-free and fully coalesced AlN was grown on such substrates. Extended defect analysis comparing X-ray diffraction, electron channeling contrast imaging and selective defect etching revealed a threading dislocation density of about 109 cm-2. However, for c-plane sapphire offcut of 0.2° towards m direction the AlN surface shows step bunches with a height of 10 nm. The detrimental impact of these step bunches on subsequently grown AlGaN multi-quantum-wells is investigated by cathodoluminescence and transmission electron microscopy. By reducing the sapphire offcut to 0.1° the formation of step bunches is successfully suppressed. On top of such a sample an AlGaN-based UVC LED heterostructure is realized emitting at 265 nm and showing an emission power of 0.81 mW at 20 mA (corresponds to an external quantum efficiency of 0.86 %)

    Structural and luminescence imaging and characterisation of semiconductors in the scanning electron microscope

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    The scanning electron microscopy techniques of electron backscatter diffraction (EBSD), electron channelling contrast imaging (ECCI) and hyperspectral cathodoluminescence imaging (CL) provide complementary information on the structural and luminescence properties of materials rapidly and non-destructively, with a spatial resolution of tens of nanometres. EBSD provides crystal orientation, crystal phase and strain analysis, whilst ECCI is used to determine the planar distribution of extended defects over a large area of a given sample. CL reveals the influence of crystal structure, composition and strain on intrinsic luminescence and/or reveals defect-related luminescence. Dark features are also observed in CL images where carrier recombination at defects is non-radiative. The combination of these techniques is a powerful approach to clarifying the role of crystallography and extended defects on a materials' light emission properties. Here we describe the EBSD, ECCI and CL techniques and illustrate their use for investigating the structural and light emitting properties of UV-emitting nitride semiconductor structures. We discuss our investigations of the type, density and distribution of defects in GaN, AlN and AlGaN thin films and also discuss the determination of the polarity of GaN nanowires

    Scanning electron microscope as a flexible tool for investigating the properties of UV-emitting nitride semiconductor thin films

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    In this paper we describe the scanning electron microscopy techniques of electron backscatter diffraction, electron channeling contrast imaging, wavelength dispersive X-ray spectroscopy, and cathodoluminescence hyperspectral imaging. We present our recent results on the use of these non-destructive techniques to obtain information on the topography, crystal misorientation, defect distributions, composition, doping, and light emission from a range of UV-emitting nitride semiconductor structures. We aim to illustrate the developing capability of each of these techniques for understanding the properties of UV-emitting nitride semiconductors, and the benefits were appropriate, in combining the techniques

    Advances in electron channelling contrast imaging and electron backscatter diffraction for imaging and analysis of structural defects in the scanning electron microscope

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    In this article we describe the scanning electron microscopy (SEM) techniques of electron channelling contrast imaging and electron backscatter diffraction. These techniques provide information on crystal structure, crystal misorientation, grain boundaries, strain and structural defects on length scales from tens of nanometres to tens of micrometres. Here we report on the imaging and analysis of dislocations and sub-grains in nitride semiconductor thin films (GaN and AlN) and tungsten carbide-cobalt (WC-Co) hard metals. Our aim is to illustrate the capability of these techniques for investigating structural defects in the SEM and the benefits of combining these diffraction-based imaging techniques

    Expanding the genetic heterogeneity of intellectual disability

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    Intellectual disability (ID) is a common morbid condition with a wide range of etiologies. The list of monogenic forms of ID has increased rapidly in recent years thanks to the implementation of genomic sequencing techniques. In this study, we describe the phenotypic and genetic findings of 68 families (105 patients) all with novel ID-related variants. In addition to established ID genes, including ones for which we describe unusual mutational mechanism, some of these variants represent the first confirmatory disease-gene links following previous reports (TRAK1, GTF3C3, SPTBN4 and NKX6-2), some of which were based on single families. Furthermore, we describe novel variants in 14 genes that we propose as novel candidates (ANKHD1, ASTN2, ATP13A1, FMO4, MADD, MFSD11, NCKAP1, NFASC, PCDHGA10, PPP1R21, SLC12A2, SLK, STK32C and ZFAT). We highlight MADD and PCDHGA10 as particularly compelling candidates in which we identified biallelic likely deleterious variants in two independent ID families each. We also highlight NCKAP1 as another compelling candidate in a large family with autosomal dominant mild intellectual disability that fully segregates with a heterozygous truncating variant. The candidacy of NCKAP1 is further supported by its biological function, and our demonstration of relevant expression in human brain. Our study expands the locus and allelic heterogeneity of ID and demonstrates the power of positional mapping to reveal unusual mutational mechanisms
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