Discriminant analysis as a tool to identify catfish (Ariidae) species of the excavated archaeological otoliths

Catfish otoliths excavated from two archaeological sites in Kuwait, Sabiyah (ca. 7000 Years Before Present) and Al-Khidr, ca. 4000 YBP, were compared with those of Kuwait’s modern catfish. Otoliths from Kuwait’s four species of catfish, Netuma bilineata, N. thalassina, Plicofollis dussumieri, and P. tenuispinis were collected after recording total length and weight. Data recorded for both ancient and modern otoliths, including annual ring (age), weight, length and four otolith radii from transverse sections, were subject to discriminant analysis to differentiate among species and develop classification functions for otoliths. Comparisons of the results from the ancient and modern otoliths showed that most of the excavated otoliths (78% from Sabiyah and 100% from Al-Khidr) belong to the two presently dominate species N. bilineata and P. tenuispinis, indicating that ichthyofauna of Kuwait Bay may not have changed much in the past 7000 years.     

An Efficient Circuit Model for the Analysis and Design of Rectangular Plasmonic Resonators

An efficient circuit model is proposed for studying the electromagnetic characteristics of rectangular plasmonic cavities. The proposed model comprised a finite size transmission line terminated by scalar load impedances at its both ends. It is capable of the fast extraction of resonance frequencies, quality factors, and mode profiles of plasmonic resonators made by carving rectangles in metallic medium. The accuracy of the proposed model is assessed using the fully numerical finite difference time domain technique. It is employed for analysis and design purposes.     

Fiber-based tissue engineering: Progress,challenges, and opportunities

Tissue engineering aims to improve the function of diseased or damaged organs by creating biological substitutes. To fabricate a functional tissue, the engineered construct should mimic the physiological environment including its structural, topographical, and mechanical properties. Moreover, the construct should facilitate nutrients and oxygen diffusion as well as removal of metabolic waste during tissue regeneration. In the last decade, fiber-based techniques such as weaving, knitting, braiding, as well as electrospinning, and direct writing have emerged as promising platforms for making 3D tissue constructs that can address the abovementioned challenges. Here, we critically review the techniques used to form cell-free and cell-laden fibers and to assemble them into scaffolds. We compare their mechanical properties, morphological features and biological activity. We discuss current challenges and future opportunities of fiber-based tissue engineering (FBTE) for use in research and clinical practice.     

New intercalated layer silicate nanocomposites based on synthesized starch-g-PCL prepared via solution intercalation and in situ polymerization methods: As a comparative study

Starch-g-polycaprolacton (Starch-g-PCL) nanocomposites have been prepared with graft polymerization through in situ ring-opening polymerization of ε-caprolacton in the presence of starch and Sn(Oct)₂ (Tin(II) 2-ethyl hexanoate) as an initiator/catalyst. A surface-modified montmorillonite by dimethyl (hydrogenated tallow alkyl) ammonium cation, was used. In fact, the related nanocomposites prepared via two methods in solution and in situ with introducing different amount of loading clay. The effect of swelling time on d-spacing of silicate layers was investigated and the obtained nanocomposites were analyzed using X-ray diffraction technique. The morphology of the synthesized nanocomposites examined using Scanning Electron Microscopy (SEM) and also the thermal degradation behavior of the prepared nanocomposites accomplished with using TGA.     

Analysis of the Transient Response of a Dual-Fed RC Transmission Line

The transient analysis of a uniform transmission line of finite length is considered in this paper. For the first time this paper provides an analytical expression for the time-domain response of an RC transmission line, which is stimulated by a step function that is fed into both ends of the transmission line. In particular, we find an analytical expression for the step response at the center of the transmission line, in order to determine the worst-case rise time. This is of interest, for example, in large charge-coupled device (CCD) arrays, where long polysilicon lines are dual-fed in order to mitigate degradation in rise time. The analytical expressions for the RC transmission line are supported by computer-simulated lumped RC models.     

Association of Vitamin D Receptor Polymorphisms (FokI (Rs2228570), ApaI (Rs7975232), BsmI (Rs1544410), and TaqI (Rs731236)) with Gastric Cancer in a Kurdish Population from West of Iran

Background:The association of 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) and its receptor, vitamin D receptor (VDR), with cancer types have been studied. However, there are controversial findings regarding the association of specific VDR polymorphisms with different kinds of cancers. In the current study, we investigated the association of VDR polymorphisms (Fok1 (rs2228570), ApaI (rs7975232), BsmI (rs1544410), and TaqI (rs731236)) with the risk of gastric cancer in a Kurdish population of Kermanshah in Iran for the first time. Methods:In this case-control study, the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used in 99 gastric cancer patients and 100 healthy subjects as controls.Results:The frequencies of f (FokI), b (BsmI), t (TaqI), and a (ApaI) alleles were: 55.6%, 27.3%, 62.1%, and 44.95% in the patient group, respectively and 42%, 29.5%, 54.5%, and 46.0% in the control group, respectively. Analysis of the results indicated that there was a positive association between the frequency of FokI genotypes with gastric cancer risk (p= 0.021). However, no statistically significant association of BsmI, Taq1, and ApaI polymorphisms of VDR was detected in gastric patients when compared with healthy individuals.Conclusion:VDR-FokI polymorphism could increase the risk of GC development and predispose to the disease by mechanisms.Key Words: Gastric cancer, PCR-RFLP, Polymorphism, Vitamin D receptor     

Performance Evaluation of TCP over Optical Channels and Heterogeneous Networks

Next generation optical networks will soon provide users the capability to request and obtain end-to-end all optical 10 Gbps channels on demand. Individual users will use these channels to exchange large amounts of data and support applications for scientific collaborative work. These new applications, which expect steady transfer rates in the order of Gbps, will very likely use either TCP or a new transport layer protocol as the end-to-end communication protocol. In this paper, we investigate the performance of TCP and newer TCP versions over High Bandwidth Delay Product Channels (HBDPC), such as the on demand optical channels described above. In addition, we investigate the performance of these new TCP versions over wireless networks and according to old issues such as fairness. This is particularly important to make adoption decisions. Using simulations, we show that (1) the window-based mechanism of current TCP implementations is not suitable to achieve high link utilization and (2) congestion control mechanisms, such as the one utilized by TCP Vegas and Westwood are more appropriate and provide better performance. We also show that new TCP proposals, although perform better than current TCP versions, they still perform worse than TCP Vegas. In addition, we found that even though these newer versions improve TCP's performance over their original counterparts in HBDPC, they still have performance problems in wireless networks and present worse fairness problems than their old counterparts. We conclude that all these versions are still based on TCP's AIMD strategy or similar and therefore continue to be fairly blind in the way they increase and decrease their transmission rates. TCP will not be able to utilize the foreseen optical infrastructure adequately and support future applications if not redesigned to scale.     

Inside Cover: Adaptive Boosting (AdaBoost)‐based multiwavelength spatial frequency domain imaging and characterization for ex vivo human colorectal tissue assessment

A multi‐wavelength Spatial Frequency Domain Imaging (SFDI) utilizes structured illumination to provide absorption and reduced scattering coefficient maps of colorectal tissue. Combining SFDI with a Machine Learning algorithm ‐ AdaBoost, different types of colorectal tissues including normal, adenomatous polyp and cancer, can be differentiated with high accuracy. This new technique provides a potential method to assist in colorectal cancer screening. Further details can be found in the article by Shuying Li, Yifeng Zeng, William C. Chapman Jr, et al. ( e201960241 ).

     

Adaptive Boosting (AdaBoost)‐based multiwavelength spatial frequency domain imaging and characterization for ex vivo human colorectal tissue assessment

The current gold standard diagnostic test for colorectal cancer remains histological inspections of endoluminal neoplasia in biopsy specimens. However, biopsy site selection requires visual inspection of the bowel, typically with a white‐light endoscope. Therefore, this technique is poorly suited to detect small or innocuous‐appearing lesions. We hypothesize that an alternative modality—multiwavelength spatial frequency domain imaging (SFDI)—would be able to differentiate various colorectal neoplasia from normal tissue. In this ex vivo study of human colorectal tissues, we report the optical absorption and scattering signatures of normal, adenomatous polyp and cancer specimens. An abnormal vs. normal adaptive boosting (AdaBoost) classifier is trained to dichotomize tissue based on SFDI imaging characteristics, and an area under the receiver operating characteristic (ROC) curve (AUC) of 0.95 is achieved. We conclude that AdaBoost‐based multiwavelength SFDI can differentiate abnormal from normal colorectal tissues, potentially improving endoluminal screening of the distal gastrointestinal tract in the future.     

The effect of chromium on parameters related to iron metabolism

The effect of chromium on some parameters related to iron metabolism was investigated. Preliminary experiments showed that this metal ion was taken up by serum proteins and was dependent on the amount of chromium present in the medium. It was also shown that the uptake of iron was reduced significantly in the presence of chromium. In vivo study showed that the serum levels of iron and total iron binding capacity (TIBC) were reduced by 28 and 11%, respectively, following daily administration of chromium (1 mg/kg) for 45 d. Serum ferritin was reduced by 22% under this condition. Hematocrit and hemoglobin levels were also affected in chromium-treated animals and were both reduced by 17%. Spectrophotometric titration of each individual amino acid located in the iron binding site of transferrin revealed that tyrosin might be the most suitable ligand for the binding of chromium to transferrin. These results suggest that chromium may compete with iron in binding to apo-transferrin, and influence iron metabolism and its related biochemical parameters.