Physicochemical Characteristics of Date Powder Produced in a Pilot-Scale Spray Dryer

Date fruit is a good source of bioactive compounds and natural sugar. It has the potential to be utilized as a substitute for added sugar. Although several forms of dates—such as fresh dates, date paste, and date syrup—are available in the market and used for different applications, free-flow date powder would be highly beneficial in improving shelf-life, ease of handling, and blendability with various foods prepared domestically and in industry. The objective of this study was to produce date powder in a pilot-scale spray dryer and determine its physicochemical qualities. Date powder was produced at eight processing conditions (2 carrier agents (maltodextrin (MD) and gum arabic (GA) × 2 inlet air temperature (150°C and 170°C) × 2 feedstock flow rates (25 ml/min and 40 ml/min)). To the carrier agent was added at 0.4 kg per 1.0 kg of date fruits (dry weight basis), and the feedstock to the spray dryer was prepared at 20% concentration. Date powder was obtained in all eight treatments. Color (L*a*b* values), moisture content, bulk density, wettability, solubility index, hygroscopicity, microstructure analysis (using scanning electron microscope (SEM)), and total phenolic compounds were determined for the spray-dried date powder. The physicochemical characteristics of date powder varied significantly with respect to the processing conditions. Although physical properties of date powder were significantly affected by the carrier agent, there was no difference in total phenolic compounds between date powders produced with MD and GA. An SEM study revealed that date powder produced with MD had smooth, regular-shaped spherical particles but with severe agglomeration. Date powder with GA had relatively smaller particles of irregular sphere with dented surfaces.     

Phosphotungstic Acid: An Efficient Catalyst for the Aqueous Phase Synthesis of Bis-(4-hydroxycoumarin-3-yl)methanes

In this present work, we report that phosphotungstic acid provides a simple, efficient and environmentally benign route is a two-component one-pot domino Knoevenagel-type condensation/Michael reaction between 4-coumarin derivative and an aldehyde in water as a solvent in shorter duration with high yields.      

Corrosion Behavior of Bare,Cr3C2-25%(NiCr), and Cr3C2-25%(NiCr)+0.4%CeO2-Coated Superni 600 Under Molten Salt at 900 °C

Cr₃C₂-25(NiCr) and Cr₃C₂-25(NiCr)+0.4%CeO₂ coatings were deposited on nickel-based superalloy Superni 600 by Detonation-gun technique. Studies were conducted on bare and coated alloys in molten salt environment (Na₂SO₄-25%NaCl) at 900 °C under cyclic condition. Characterization of the corrosion product was done using field emission scanning electron microscopy/energy dispersive spectroscopy and x-ray diffraction techniques. The bare Superni 600 shows penetration of corrosion beneath the metal layer thereby indicating internal oxidation. The coating of Cr₃C₂-25(NiCr) with 0.4%CeO₂ leads to the formation of adherent scale.     

Electroporation therapy: a new approach for the treatment of headand neck cancer

Electroporation can deliver exogenous molecules like drugs and genes into cells by pulsed electric fields through a temporary increase in cell membrane permeability. This effect is being used for the treatment of cancer by intratumoral injection of low dosage of an otherwise marginally effective chemotherapeutic drug, bleomycin. Application of a pulsed electric field results in substantially higher uptake of the drug and enhanced killing of the cancer cells than is possible by conventional methods. The MedPulser, a new treatment system for local electroporation therapy (EPT) of head and neck tumors was developed and is described in this paper. EPT with bleomycin has been found to be very effective in killing cancer cells in vitro, in mouse tumor xenografts in vivo, and in tumors in humans. Ten head and neck cancer patients with recurring or unresponsive tumors were enrolled in a Phase I/II clinical trial. Treatment of the entire tumor mass in each of eight patients resulted in five complete responses confirmed by biopsy and MRI, and three partial responses (> or = 50% shrinkage). Two additional patients who received partial treatment of their tumor mass had local response where treated, but no overall lesion remission. Duration of the complete responses ranges from 2-10 months to date. All patients tolerated the treatment well with no significant local or systemic adverse effects.     

Supramolecular Capsules Derived from Resorcin[4]arenes by H-Bonding and Metal Coordination: Synthesis,Characterization, and Single-Molecule Force Spectroscopy

Self-assembly by H-bonding and by metal-coordination of functionalized calix[4]arenes and cavitands to large supramolecular capsules is described. In addition, a new method of analyzing supramolecular recognition processes at the single molecule level is discussed. By measuring interaction forces in a hydrogen-bonded assembly using single-molecule force spectroscopy (SMFS), the dynamics of the self-assembly process can be evaluated. In the future, consequent application of this new technique will influence supramolecular design principles and the use of non-covalent interactions as construction elements in the field of nanotechnology.     

A Call-Admission Control (CAC) Algorithm for Providing Guaranteed QoS in Cellular Networks

Future broadband wireless access systems are expected to integrate various classes of mobile terminals (MTs), each class with a different type of quality of service (QoS) requirement. When the load on a wireless network is high, the guarantee of QoS for each class of MTs is a challenging task. This study considers two classes of MTs—profiled MTs and nonprofiled or regular MTs. It is assumed that profiled users require a guaranteed QoS. The measure of QoS is the probability of forced termination of a call that was allowed to access the network. Two previous handoff prioritization schemes—(i) prerequest scheme and (ii) guard channel scheme—decrease handoff failure (and hence forced termination). In this work, we compare and contrast both the schemes through extensive simulation and we find that neither guard channel nor channel prerequest scheme can guarantee a desired level of QoS for the profiled MTs. We then propose a novel call-admission control (CAC) algorithm that can maintain any desired level of QoS, while the successful call completion rate is very high. In the proposed algorithm, the new call arrival rate is estimated continuously, and when the estimated arrival rate is higher than a predetermined level, some new calls are blocked irrespective of the availability of channels. The objective of this new call preblocking is to maintain a cell's observed new call arrival rate at no more than the predetermined rate. We show that the proposed method can guarantee any desired level of QoS for profiled users.     

Solid-State Polymerization Behavior of 1,3-Bis(3-quinolyl)-1,4-butadiyne

Summary 1,4-Bis(3-quinolyl)-1,3-butadiyne (DQ) is known to be polymerized in solid state to give the corresponding polydiacetylene. However, the polymer yield of DQ bulk crystals is low. Thus, we prepared several types of DQ crystals by different procedures to find the reason for the low polymer yield. We found three modifications of DQ crystals and they were evaluated by spectroscopic measurements and X-ray diffraction. DQ bulk crystals (Crystal I) and thermally grown DQ crystals on Crystal I (Crystal II) have the same structure classified to Type A, which gives regular polydiacetylene structure in low polymer yields. DQ crystals grown on glass plates by sublimation (Crystal III) belong to the second modification of Type B. DQ nanocrystals prepared by the reprecipitation method (Crystal IV) are Type B, and thermally grown DQ crystals on nanocrystals (Crystal V) are Type C. Crystals of Types B and C could be polymerized in low yields without showing excitonic absorption of polydiacetylene indicating irregular polymerization other than 1,4-addition. For crystals of Type A, we found that the 1,4-addition polymerization proceeded only in near-surface portions of the crystals. It can be plausibly explained that mobile monomers in the near-surface portion are only able to take part in their polymerization, resulting in low polymer conversion.     

Aloe vera incorporated biomimetic nanofibrous scaffold: a regenerative approach for skin tissue engineering

Aloe vera (AV) is one of the medicinal herbs with a well-established spectrum of wound healing, antimicrobial and anti-inflammatory property. AV-mediated therapeutics present significant tissue regenerative activity by modulating the inflammatory and proliferative phases of wound healing. The purpose of the present work was to combine the biological properties of AV and the advantages of electrospun meshes to prepare a potent transdermal biomaterial. The polycaprolactone (PCL) containing 5 and 10 wt % of lyophilized powder of AV was studied for electrospinning into nanoscale fiber mats and compared with PCL/Collagen blend for dermal substitutes. SEM revealed the average diameters of PCL, PCL-AV 5 %, PCL-AV 10 % and PCL/Collagen nanofiber scaffolds in the range of 519 ± 28, 264 ± 46, 215 ± 63 and 249 ± 52 nm, respectively. PCL-AV 10 % nanofiber scaffolds showed finer fiber morphology with improved hydrophilic properties and higher tensile strength of 6.28 MPa with a Young’s modulus of 16.11 MPa desirable for skin tissue engineering. The nanofibers were then used to investigate differences in biological responses in terms of proliferation and cell morphology of mice dermal fibroblasts. It was found that PCL-AV 10 % nanofibrous matrix favored cell proliferation compared to other scaffolds which almost increased linearly by (p ≤ 0.01) 17.79 % and (p ≤ 0.01) 21.28 % compared to PCL on sixth and ninth day. CMFDA dye expression, secretion of collagen and F-actin expression were significantly increased in PCL-AV 10 % scaffolds compared to other nanofibrous scaffolds. The obtained results proved that the PCL-AV 10 % nanofibrous scaffold is a potential biomaterial for skin tissue regeneration.     

Has the increase in world-wide openness to trade worsened global income inequality?

This article contributes to our understanding of the relationship between globalization and world income inequality by analyzing the trend in global inequality for the period 1960–1989. Using Penn World Tables data and time-series econometric techniques, it analyzes how the increase in worldwide openness to trade has been related to global income inequality during this period. When differential population growth rates among the countries are taken into account, the results indicate that (i) global income inequality exhibited a downward trend between 1960 and 1989, and (ii) while there is a positive relationship between inequality and openness, the relationship is not statistically significant. Received: 22 December 2000 / Accepted: 29 May 2001     

Sustained local delivery of heparin to the rabbit arterial wall with an electroporation catheter

Since the rapid expansion of managed care coupled with dramatic reductions in lengths of inpatient stay, there is widespread concern that the emphasis on cost containment is eclipsing attention to patient care. The present study was undertaken to evaluate speculations that the majority of short-stay (less than 48 hours) admissions to a psychiatric inpatient service at a large teaching hospital in the midwestern United States consisted of public pay patients who were rapidly transferred to area state hospitals. Using two cases mix measures, severity of illness and changes in acuity and clinical outcomes of a sample of short-stay (n = 77) and longer stay (n = 145) admissions were compared. Short-stay admissions, although similar to longer stay patients in terms of demographics, Axis I diagnosis, payer status, and appropriateness of admission, are clinically distinct. The use of nonhospital alternatives in treating a subsample of suicidal patients and the implications for improved mental health services delivery are discussed.