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Internet of things (IoT) is becoming widely adopted in our daily lives. These devices range from basic sensors to very powerful and capable computing devices. However, there are many security issues associated with IoT. One major attack that is associated with IoT devices is the Denial of Service (DoS) attacks. In order to circumvent this attack, reliable and secure data transfer over the network is required. In this paper we introduce a secure distributed routing algorithm that aims to detect malicious nodes with a network. This is achieved by validating the source of the data being transmitted over the network through providing a fingerprint from the IoT device. The fingerprint is composed from data from the sensors already existing in the IoT device. Since these devices are not in an identical physical location, the fingerprint will vary from one device to another. We test our system on an implementation of a network of IoT devices and validate the results. Moreover, we provide simulation results for the secure routing protocol. Our implementation and simulation indicate that providing a fingerprint for the IoT devices and using it to provide secure routing will help avoid DoS attacks.

The authors wish to make the following corrections to the main text in the published paper [1]. In this paper, the weight of CuCl2 should be changed from 5 mg to 5 g to provide accurate recipe for the IN718 etchant.[...]

Fabrication of solar and electronic silicon wafers involves direct contact between solid, liquid and gas phases at near equilibrium conditions. Understanding of the phase diagrams and thermochemical properties of the Si-dopant binary systems is essential for providing processing conditions and for understanding the phase formation and transformation. In this work, ten Si-based binary phase diagrams, including Si with group IIIA elements (Al, B, Ga, In and Tl) and with group VA elements (As, Bi, N, P and Sb), have been reviewed. Each of these systems has been critically discussed on both aspects of phase diagram and thermodynamic properties. The available experimental data and thermodynamic parameters in the literature have been summarized and assessed thoroughly to provide consistent understanding of each system. Some systems were re-calculated to obtain a combination of the best evaluated phase diagram and a set of optimized thermodynamic parameters. As doping levels of solar and electronic silicon are of high technological importance, diffusion data has been presented to serve as a useful reference on the properties, behavior and quantities of metal impurities in silicon. This paper is meant to bridge the theoretical understanding of phase diagrams with the research and development of solar-grade silicon production, relying on the available information in the literature and our own analysis.

The Mg–Mn–Nd isothermal section at 450 °C was constructed experimentally using solid–solid diffusion couples and key alloys. Diffusion couples and key alloys were annealed at the same temperature for different annealing time periods to understand the diffusion behavior of the system components, and to achieve the phase equilibrium in the system. The phase relations and solubility limits were determined using scanning electron microscope coupled with wave/energy dispersive X-ray spectrometers, X-ray diffraction and metallography. No ternary compounds could be observed in this system at 450 °C. The microstructures of the diffusion zones showed Mn either as a pure element or as a solute atom. However, microstructures of the annealed key alloys near the Mn-rich side showed the formation of Mn 17 Nd 2 at 450 °C. Other Mn binary compounds, Mn 2 Nd and Mn 23 Nd 6 , were observed only in the as-cast alloys, because they are not stable at 450 °C. The experiments showed that Mn remained stationary in some diffusion zones forming Mn+(MgNd), Mn+(Mg 3 Nd) and Mn+Mg 41 Nd 5 two-phase regions. However, some of Mn atoms were diffusing in the system forming a continuous thin layer of pure Mn at the interface of pure Mg end-member, or to form (α-Nd) Mg,Mn , (MgNd) and (Mg 3 Nd) ternary solid solutions. The solubility of Mn in these solutions was estimated as 3.0, 13.0 and 3.5 at.% Mn, respectively. Since Mn is in equilibrium with most of the phases in the system, the phase boundary lines are pointing toward Mn-rich corner except that of (α-Nd) Mg,Mn +(MgNd)+Mn 17 Nd 2 three-phase field. This was confirmed based on the consistency of the results obtained from diffusion couples and key alloys.

Binary interdiffusion data as function of composition in the Mg–{Ce, Nd, Zn} and Zn–{Ce, Nd} systems were obtained experimentally using solid–solid diffusion couples. For the studied systems, all intermetallic compounds were produced, based on the equilibrium phase diagrams, eliminating the problem of missing compounds in the diffusion couples found in the literature. The composition profiles were obtained using wavelength dispersive spectroscopy line-scans across diffusion couples. The composition-dependent diffusion coefficient at each interface was determined using Boltzmann–Matano analysis. For the available literature data for some of the compounds in the Mg–{Ce, Nd, Zn} systems, the calculated interdiffusion coefficients were in good agreement. No diffusion data regarding Zn–{Ce, Nd} systems could be found in the literature. The activation energy and the preexponential factor of the growth of the Mg–{Ce, Nd, Zn} compounds were determined using Arrhenius equation. The activation energies of the growth of the Mg–Ce compounds showed relatively higher values than those of Mg–Nd and Mg–Zn compounds.

Magnesium-based alloys are becoming a major industrial material for structural applications because of their potential weight saving characteristics. All the commercial Mg alloys like AZ, AM, AE, EZ, ZK, and so forth series are multicomponent and hence it is important to understand the phase relations of the alloying elements with Mg. In this work, eleven essential Mg-based binary systems including Mg-Al/Zn/Mn/Ca/Sr/Y/Ni/Ce/Nd/Cu/Sn have been reviewed. Each of these systems has been discussed critically on the aspects of phase diagram and thermodynamic properties. All the available experimental data has been summarized and critically assessed to provide detailed understanding of the systems. The phase diagrams are calculated based on the most up-to-date optimized parameters. The thermodynamic model parameters for all the systems except Mg-Nd have been summarized in tables. The crystallographic information of the intermetallic compounds of different binary systems is provided. Also, the heat of formation of the intermetallic compounds obtained from experimental, first principle calculations and CALPHAD optimizations are provided. In addition, reoptimization of the Mg-Y system has been done in this work since new experimental data showed wider solubility of the intermetallic compounds.

The isothermal section of the Ce-Mg-Mn phase diagram at 723 K (450 °C) was established experimentally by means of diffusion couples and key alloys. The phase relationships in the complete composition range were determined based on six solid–solid diffusion couples and twelve annealed key alloys. No ternary compounds were found in the Ce-Mg-Mn system at 723 K (450 °C). X-ray diffraction and energy-dispersive X-ray spectroscopy spot analyses were used for phase identification. EDS line-scans, across the diffusion layers, were performed to determine the binary and ternary homogeneity ranges. Mn was observed in the diffusion couples and key alloys microstructures as either a solute element in the Ce-Mg compounds or as a pure element, because it has no tendency to form intermetallic compounds with either Ce or Mg. The fast at. interdiffusion of Ce and Mg produces several binary compounds (CexMgy) during the diffusion process. Thus, the diffusion layers formed in the ternary diffusion couples were similar to those in the Ce-Mg binary diffusion couples, except that the ternary diffusion couples contain layers of Ce-Mg compounds that dissolve certain amount of Mn. Also, the ternary diffusion couples showed layers containing islands of pure Mn distributed in most diffusion zones. As a result, the phase boundary lines were pointing toward Mn-rich corner, which supports the tendency of Mn to be in equilibrium with all the phases in the system.

Summary Background/Purpose Skin aging can be classified into chronological aging and photoaging. Cyclooxygenase-2 (COX-2) may be involved in ultraviolet-induced inflammation, photocarcinogenesis and the aging process. Studies done focused on assessing COX-2 expression after acute ultraviolet exposure and in photocarcinogenesis. Comparative assessment of COX-2 expression in chronological aging and photoaging was not previously studied. We aimed to compare COX-2 expression in chronological aging and photoaging. Methods Sixty participants were included (20 with chronological aging, 20 with photoaging, and 20 non-skin-aged contributors as controls). Fitzpatrick skin type and Glogau's photoaging type were assessed. Immunohistochemical evaluation of COX-2 was done in biopsies from sun-protected skin in the chronological aging and control groups, and from sun-exposed skin in the photoaging group. Results Comparison between each two groups showed a high statistically significant difference, with the highest percentage of mild, moderate and marked expression in the control, chronological aging and photoaging groups, respectively. A high statistically significant positive correlation was found between grading of solar elastosis in the photoaging group and COX-2 expression parameters. Conclusion COX-2 expression is significantly higher in chronologically aged and photoaged skin than the normal young skin. This level of expression is significantly higher in photoaging than in chronological aging. COX-2 expression is positively related with the degree of solar elastosis in photoaging.

The complete Mn–Nd phase diagram was established experimentally by means of key samples and diffusion couple techniques. The phase transformation temperatures, crystal structures and phase equilibria were studied using differential scanning calorimetry (DSC), X-ray diffraction (XRD), electron probe microanalysis (EPMA), and scanning electron microscope (SEM) techniques. Three compounds in the Mn-rich side and two terminal solid solutions in the Nd-rich side were observed. The compounds Mn2Nd, Mn23Nd6, and Mn17Nd2 form peritectically at 850, 940, and 1025 1C, respectively. The eutectoidal decompositions of the compounds, Mn2Nd, and Mn23Nd6, were confirmed in the temperature ranges of 650–550 and 550–400 1C, respectively, using EPMA. The maximum solubility of Mn in DHCP-Nd was found to be 2.3 at% Mn at the 685 1C eutectic temperature. The solvus line of DHCP-Nd was determined using EPMA. The solubility of Mn in BCC-Nd was extrapolated from DSC data to be 5.0 at% Mn at 728 1C. The existence of a Mn17Nd2 phase of the Th2Ni17 type structure was confirmed using EPMA and XRD. The system was modelled using CALPHAD methodology. The quasi-chemical model (QCM) was used to describe the liquid phase, the terminal solution phases were modeled as substitutional solutions using the random mixing model, and the intermetallic compounds were treated as stoichiometric phases. The enthalpies of formation of the system compounds were calculated using the electronic density functional method. The resulting enthalpy of mixing was in good agreement with the literature.

Purpose : To compare visual outcomes, intraoperative and postoperative complications of 25-gauge transconjunctival sutureless vitrectomy (25-G TSV) versus conventional 20-gauge vitrectomy in epiretinal membrane (ERM) surgery. Methods : A retrospective comparative study was conducted on 200 eyes with idiopathic ERM who underwent either primary 20-gauge vitrectomy (n=95) or 25-G TSV (n=105) with 6 months follow up. The following parameters were collected and compared : age, gender, best corrected visual acuity (BCVA), intraocular pressure (IOP), postoperative anterior chamber inflammation, intraoperative and postoperative complications. Results : Twenty-five gauge group achieved a significantly better vision at the 1st postoperative month (p=0.008) and a significantly higher incidence of visual improvement 6 months postoperatively (p=0.04) than 20-gauge group. Intraocular pressure was significantly higher at the 1st, 3rd and 6th postoperative months compared with baseline in the 20-G group. However, in the 25-gauge group IOP remained near to the baseline at the same period. Twenty five-gauge group achieved a significantly lower anterior chamber inflammation and a lower incidence of postoperative cystoid macular edema (CME) (p=0.01), hyphema (p=0.000) and after cataract (p=0.000) than 20-gauge group. Conclusions : The 25-gauge sutureless vitrectomy achieves rapid and higher visual improvement, less postoperative inflammation and complications than the 20-gauge vitrectomy in ERM surgery.

Objective To evaluate the effect and safety of laparoscopic pyeloplasty in the treatment of pelvi-ureteric junction obstruction (PUJO). Patients and methods In 34 patients, laparoscopic dismembered pyeloplasty was used to treat primary PUJO. Information was obtained for symptoms, results of a nuclear scan before and after surgery, intraoperative blood loss, operative duration, stenting method, and hospital stay. Under general anaesthesia and in the flank position, a 10 mm trocar was first placed above the umbilicus; three 5 mm working ports were then placed. The ureter and pelvis were freed from surrounding adhesions. The obstructive pelvi-ureteric segment was then excised, and the opened point of the ureter spatulated. Ureteropyeloplasty between the lower pole, pelvis and spatulated ureter was made using a 4-0 polyglactin suture around a JJ stent. Results The mean (SD) preoperative nuclear scan result was 23.6 (6.4) mL/min, with retention of tracer. The median operative duration was 200 min, and the median blood loss 120 mL. All patients were stented with a JJ stent. The mean hospital stay was 5 days. The final results were assessed at 6 months after surgery, when the mean (SD) nuclear scan result was 30 (7.4) mL/min. Conclusion Laparoscopic pyeloplasty is a safe and effective option which can produce satisfactory results both clinically and radiologically.

Objective To test the efficacy, safety, and tolerability of a novel surgical alternative for formation of a neovagina in patients with vaginal aplasia. Design Technique and instrumentations. Setting A specialized endoscopic surgery center. Patient(s) Four patients with complete vaginal aplasia, three of them without a uterus and one with a functioning uterus. Intervention(s) A silicone Foley catheter sutured to the distal end of a sharp curved needle with a wide eye attached to a plastic handle and passed extraperitoneally into the space of Retzius followed by its inflation and upward traction for 8 days. Clinical and magnetic resonance imaging (MRI) follow-up were done. Main Outcome Measure(s) Operative time, complication rate, tolerability of traction and retraction, reintervention rate, width and length of the newly formed vagina, and postoperative feasibility of intravaginal sexual intercourse for married cases. Result(s) The results were satisfactory (normal length and width of neovagina), without complications and with acceptable tolerability and normal sexual life within 8–10 days postoperatively for the married women. Conclusion(s) Both clinical and MRI follow-up confirmed that retropubic balloon vaginoplasty is a simple, fast, tolerable, safe, and available extraperitoneal procedure. It can be easily done by any gynecologist having basic knowledge of the anatomy of the retropubic space.

Background Proper eradication of allergic fungal sinusitis (AFS) depends on three factors: first is proper preoperative evaluation and mapping via computed tomography and MRI. Second is the availability of adequate surgical tools in experienced hands. Third is the proper postoperative endoscopic follow-up to detect and remove recurrence if possible. Aim To evaluate the role of inferior turbinectomy (IT) and partial middle turbinectomy (PMT) in patients with AFS managed by endoscopic sinus surgery (ESS) for the prevention of recurrence and adequate management of residual disease (postoperative salvage). Patients and methods A prospective, comparative, randomized study conducted from March 2016 to April 2018. In all, 28 patients suffering from AFS were included. All patients have been presented and managed at the Department of Otolaryngology, Hearing and Speech Institute. Patients have been randomized into two groups of 14 patients each (groups A and B). The patients in group A have undergone ESS only, while the patients in group B have undergone ESS plus bilateral IT and PMT. Regular follow-up visits were done every 2 months for at least 6 months for both groups. Results In group A, there was difficulty in proper assessment in 11 patients out of 14. Recurrence occurred in five patients who showed rigorous assessment, which was managed via ESS adding to the maneuver bilateral IT and PMT. In group B, only two patients were difficult out of the 14. Recurrence occurred in two patients only and was managed easily in the outpatient office. No significant complications were detected in both groups. Conclusion IT and PMT may be considered as essential steps in the surgery for AFS as they play a role in lowering the recurrence rate and facilitating better, more comfortable, and more effective postoperative management of recurrence if happened.

In this work, wetting behavior of Ti–20Zr–20Cu–20Ni brazing filler on Ti–6Al–4V substrate was studied using sessile drop technique. Effects of the substrate surface roughness, R a of ~0.40 and 0.08 µm, and heating scheme on wetting and spreading of the filler metal were evaluated. The wetting mechanism was investigated by the combination of cooling technique, thermal, compositional, and microstructural analysis. This was performed using a heat-flux DSC and an SEM equipped with EDS. The degree of wetting was evaluated by measuring the apparent dynamic contact angle between the filler drop and substrate surface and by calculating the drop spread ratio. The surface roughness of the substrate was found to have little or no effect on the final apparent contact angle. The wetting behavior of this system showed a reactive nature, because it involves dissolution of the substrate and formation of interfacial layers. Three heating schemes were used in the current study. While the high heating rate of 6.8 °C s−1 was found to limit the metallurgical reaction between the substrate and the brazing filler, in the low heating rate scheme of 1.7 °C s−1, more intense metallurgical reaction occurred between the brazing filler and the substrate. The high heating rate with soaking scheme is recommended for brazing, because it entails extensive spreading and limited metallurgical reaction between the brazing filler and the substrate.

In this paper, we present a QoS-Aware node Selection Algorithm (QASA) for routing protocols to be suitable for a particular class of opportunistic networks, when applied to the Vehicular Ad hoc Networks. Our algorithm aims to select the next-hop vehicle to communicate with, by exploiting the “bridging approach” for message forwarding i.e., vehicles on the east (west) select from west (east). The QoS metrics that are being optimized are the throughput in the network, and packets end-to-end delay. In order to provide the best network performance, the algorithm utilizes a probabilistic rebroadcasting scheme based on different network parameters including vehicle density, inter-vehicle distance, and the transmission range for the vehicles. Moreover, QASA utilizes a transmission range-based metric that can be changed as per application requirements, whether it is high throughput or minimum end-to-end delay. Simulation results show the effectiveness of our approach in terms of improved QoS metrics in different vehicular network scenarios.

Al-Mn-Zn ternary system is experimentally investigated at 400°C using diffusion couples and key alloys. Phase relationships and homogeneity ranges are determined for binary and ternary compounds using EPMA, SEM/EDS, and XRD. Reported ternary compound T3 (Al11Mn3Zn2) is confirmed in this study and is denoted as τ2 in this paper. Two new ternary compounds (τ1 and τ3) are observed in this system at 400°C. τ1 is determined as a stoichiometric compound with the composition of Al31Mn8Zn11. τ3 has been found to have homogeneity range of AlxMnyZnz (x=9–13 at%; y=11–15 at%; z=75–77 at%). The binary compounds Al4Mn and Al11Mn4 exhibit limited solid solubility of around 6 at% and 4 at% Zn, respectively. Terminal solid solution Al8Mn5 is found to have maximum ternary solubility of about 10 at% Zn. In addition, ternary solubility of Al-rich β-Mn′ at 400°C is determined as 4 at% Zn. Zn-rich β-Mn′′ has a ternary solubility of 3 at% Al. The solubility of Al in Mn5Zn21 is measured as 5 at%. Based on the current experimental results, the isothermal section of Al-Mn-Zn ternary system at 400°C has been constructed.

This paper presents a new probabilistic-based re-broadcast scheme, providing a reliable and low-collision packet forwarding in a vehicular ad hoc network. In the proposed technique called Collision-Aware REliable FORwarding, each vehicle rebroadcasts a received information on the basis of physical parameters associated with a vehicular environment, i.e., the distance from the source, the density of neighbors, and the forward transmission range. The key idea is that a node implicitly evaluates the probability that there is another node which can be more successful in rebroadcasting, that means (i) the message will be transmitted as far as possible, and (ii) will have a low number of expected collisions. Unlike other existing probability assignment schemes, our technique attempts to accurately forecast the next-hop transmission, while keeping the computation cost very low.

Purpose : To compare visual outcomes, intraoperative and postoperative complications of 25-gauge transconjunctival sutureless vitrectomy (25-G TSV) versus conventional 20-gauge vitrectomy in epiretinal membrane (ERM) surgery. Methods : A retrospective comparative study was conducted on 200 eyes with idiopathic ERM who underwent either primary 20-gauge vitrectomy (n=95) or 25-G TSV (n=105) with 6 months follow up. The following parameters were collected and compared : age, gender, best corrected visual acuity (BCVA), intraocular pressure (IOP), postoperative anterior chamber inflammation, intraoperative and postoperative complications. Results : Twenty-five gauge group achieved a significantly better vision at the 1st postoperative month (p=0.008) and a significantly higher incidence of visual improvement 6 months postoperatively (p=0.04) than 20-gauge group. Intraocular pressure was significantly higher at the 1st, 3rd and 6th postoperative months compared with baseline in the 20-G group. However, in the 25-gauge group IOP remained near to the baseline at the same period. Twenty five-gauge group achieved a significantly lower anterior chamber inflammation and a lower incidence of postoperative cystoid macular edema (CME) (p=0.01), hyphema (p=0.000) and after cataract (p=0.000) than 20-gauge group. Conclusions : The 25-gauge sutureless vitrectomy achieves rapid and higher visual improvement, less postoperative inflammation and complications than the 20-gauge vitrectomy in ERM surgery.

This paper introduces a hybrid communication paradigm for achieving seamless connectivity in Vehicular Ad hoc Networks (VANETs), wherein the connectivity is often affected by changes in the dynamic topology, vehicles’ speed, as well as the traffic density. Our proposed technique named QoS-oriented Hybrid Vehicular Communications Protocol (QoSHVCP) exploits both existing network infrastructure through a Vehicle-to-Infrastructure (V2I), as well as a traditional Vehicle-to-Vehicle (V2V) connection that could satisfy Quality-of-Service requirements. QoSHVCP is based on a V2V-V2I protocol switching algorithm, executed in a distributed fashion by each vehicle and is based on the cost function for alternative paths each time it needs to transmit a message. We utilize time delay as a performance metric and present the delay propagation rates when vehicles are transmitting high priority messages via QoSHVCP. Simulation results indicate that simultaneous usage of preexisting network infrastructure along with intervehicular communication provide lower delays, while maintaining the level of user’s performance. Our results show a great promise for their future use in VANETs.

In this paper we investigate the time delay propagation rates in a Vehicular Ad-Hoc Network, where vehicular connectivity is supported by both Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) protocols. In our vision, seamless connectivity issues in a VANET with nearby network infrastructure, can be fixed by an opportunistic choice of a vehicular protocol between V2V and V2I. Such a decision is taken by each vehicle whenever it needs to transmit messages. Our technique — called as Vehicle-to-X — represents a handoff procedure between V2V and V2I, and vice versa, in order to keep vehicles connected independent of mobility issues and traffic scenarios. We investigate the time delay as a performance metric for protocol switching, and present the time propagation rates which occur when vehicles are transmitting warning messages, via V2V or V2I. Simulation results show how the simultaneous usage of pre-existing network infrastructure, together with inter-vehicular communications, provides low delays; while traditional opportunistic vehicular communications increases the transmission time delays and does not guarantee seamless connectivity to vehicles.

To evaluate the efficacy and safety of 25-gauge transconjunctival sutureless vitrectomy (25-G TSV) in the management of vitreoretinal complications of proliferative diabetic retinopathy (PDR).A retrospective review of a noncomparative interventional case series including 200 eyes of 164 consecutive patients who underwent 25-G TSV for the management of PDR was performed. The main outcome measures were preoperative and postoperative visual acuity and intraocular pressure (IOP), the surgical success rate, and intraoperative and postoperative complications. All cases had a follow-up period of at least 6 months.The mean logarithm of the minimum angle of resolution (LogMAR) visual acuity was significantly improved from 1.55 preoperatively to 0.72 at the final visit. No intraoperative complications related to the 25-G TSV procedure were recorded. Transient hypotony was recorded in 18 eyes (9%) on postoperative day 1 and 15 eyes (7.5%) on postoperative day 5. Two of these eyes (1%) had choroidal detachment on postoperative day 5. One case showed bacterial endophthalmitis after the second surgery. The single operation and final surgical success rates were 81.5% and 98% respectively.These outcomes of 25-G TSV showed its safety and efficacy in the management of PDR.

In this demo, a new application for the wireless sensor networks (WSN) is presented. This is the first time WSN is used to in the music field, where the music is being manipulated and changed according to the movement of the dancer. Twenty-three tmote sensors have been deployed on a dancing stage, and two sensors were attached to the arms of each dancer. Information collected from sensors deployed on the stage are being sent and processed at a central location where the music being played is manipulated. This project is the first phase of collaboration in a multi-disciplinary research between the Computer Science department and the College-Conservatory of Music at the University of Cincinnati.

Summary Conductometric and spectrophotometric studies on the complexes of uranyl ions with 5-norvisnagin, 1-hydroxy-9-xanthenone and 8-hydroxyquinoline have been carried out in pure dioxane and dioxane-water mixture, D =30. In every case, conductometric titration shows breaks corresponding to the formation of more than one type of complex. For both 5-norvisnagin and 8-quinolinol breaks correspond to the ratios uranyl: ligand of 1:1, 1:2 and 1:4; with 1-hydroxy-9-xanthenone, the compositions 1:1 and 1:3 are identified. Spectrophotometric studies covering the visible and u.v. range indicate considerable stability of the 1:3 complex with 1-hydroxy-9-xanthenone (applying the molar ratio method). The continuous variation method establishes the existence of 1:2 uranyl complexes with both 5-norvisnagin and 8-quinolinol. Complexes precipitated from the above media at the stable compositions indicated, are spectrophotometrically scanned in the region 600–200 nm. Characteristic peaks for these complexes are observed at the same wave lengths as shown in solution. Microanalysis for carbon and uranium in the complexes separated are in fairly good agreement with the compositions proposed, especially for 5-norvisnagin and 8-hydroxyquinoline where pure crystals of the complexes could be prepared.