bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-Destructive Tests as Durability Indicators in Cement Mortars with Pozzolanic Substitutions
Authors: Ruiz Rosalía Ruiz , Guzmán Elia Mercedes Alonso , Molina Wilfrido Martínez , Chávez-García Hugo Luis , Perez Judith Alejandra Velázquez
Published: July 2017

Cement industry is responsible of 5-7% of CO2 emissions to the atmosphere. This is preoccupant because this is one of the greenhouse effect gases which cause global warming. Pozzolanic material incorporation in cement mortars elaboration represents a good alternative to partially substitute cement, since its chemical composition could contribute to improvement of its durability and mechanical characteristics. In this research, mortars with pozzolanic substitutions are evaluated through non-destructive tests as: capillary absorption, electrical resistivity, and ultrasonic pulse velocity to the age of 1000 days. The results suggested that the incorporation of pozzolanic material as partial substitutes of Portland cement increases the mortars properties mainly in substitutions of CBC 20%, PN 10, and 30%.
An Advanced Extreme Environment Wireless Telemetry System for Turbine Blade Instrumentation
Authors: Fraley John R. , Sparkman Brett , Minden Stephen , McConkey Joshua
Published: July 2017

As advanced natural gas power generation systems evolve, the thrust for increased efficiencies and reduced emissions results in increasingly harsh conditions inside the turbine environment. These high temperatures, pressures, and corrosive atmospheres result in accelerated rates of degradation, leading to failure of turbine materials and components. Wolfspeed, A Cree Company, Siemens Energy and Siemens Corporate Technology, in collaboration with the DoE's National Energy Technology Laboratory (NETL), are developing a reliable and long-term monitoring capability in the turbine hot gas path in the form of novel ceramic based thermocouples and wide band gap instrumentation electronics that will contribute to the overall reliability of gas turbines. When equipped with better monitoring and controls, power plants can operate with increased fuel-burning efficiency, improved process dynamics and gas concentrations, and increased overall longevity of the power plant components. This will result in increased turbine availability and a reduction in outages and maintenance costs.

The technology being developed in this program is based upon advanced techniques and innovations in nearly every aspect of high temperature electronics, including materials, subcomponents, semiconductors, electronic packaging, and system integration. The environment in which this wireless system must operate has continuous g-loads on the order of 16,000g, and temperatures exceeding 400 °C. This paper will specifically discuss the background and motivation for the high temperature instrumentation system, and will explain the high-level electrical system, the construction of the instrumentation package, the techniques utilized for integration onto rotating components, as well as the wireless power and data transmission systems. In addition to the electrical and mechanical design, this paper will also discuss results from laboratory bench testing as well as heated spin rig testing. Finally, this paper will highlight the future direction of the instrumentation system evolution, with a final objective of insertion into Siemens natural gas turbine power plants.
High Temperature, Time Domain Sensor Interface based on Phase Shifter
Authors: Chabchoub Emna , Badets Franck , Masmoudi Mohamed , Nouet Pascal , Mailly Frédérick
Published: July 2017

This paper presents resistive sensor interface circuit for high temperature applications. The presented circuit has a time-domain differential architecture. It is based on the use of voltage-controlled phase shifters to perform the signal conditioning in time domain which makes it more robust the environment's parameters, in particular the temperature. The output of the presented senor interface depends only on relative parameters of the circuit, therefore; a low sensitivity to temperature variations is achieved. The low variation of the circuit output versus temperature has been demonstrated by simulations and measurements of the fabricated prototype.
SOI Operational Amplifier Applications in 300°C Operating Environment
Authors: Chen Cheng-Po , Stoica Lucian , Andarawis Emad , Simpson Russell
Published: July 2017

A custom designed SOI operational amplifier (opamp) is used in two application circuits and characterized up to 300°C: 1. An instrumentation amplifier (in-amp) with a differential voltage gain of 100, and 2. A transimpedance amplifier (TIA) with a gain of 1.2 giga Ohm, used to sense picoamp level signals. The opamp operates with a 5-volt supply, and has rail-to-rail inputs and outputs. The open loop gain of the opamp is about 100 dB at room temperature and stays above 60 dB at 300°C.

The in-amp uses the classic three operational amplifier (opamp) architecture with off-chip feedback resistors. The closed loop gain of the in-amp remains stable at 100, up to 250°C, and drops to 95 at 300°C. Temperature dwell test shows the in-amp maintaining stable functionality at 300°C for at least 1000 hours.

The TIA also incorporates a silicon carbide diode to achieve gain compression by lowering the feedback gain when the input signal is higher, thus allowing a higher dynamic range input before the circuit output saturates.
A High Temperature Linear Wideband Power Amplifier for a Downhole Communication System
Authors: Hiemstra S. Reza , Kerrigan Brannon M. , Ha Dong S.
Published: July 2017

In order to reach previously untapped wells, the oil and gas industry continues to drill deeper, resulting in extreme operating temperatures for electronic systems. It is essential for electronic circuits and systems to be able to withstand extreme temperatures. The proposed power amplifier (PA) intends for a downhole communication system operating at an ambient temperature of 230 °C. The proposed PA is designed with Qorvo T2G6003028-FL GaN on SiC HEMT, which offers a high junction temperature. The proposed PA can operate reliably up to an ambient temperature of 230 °C with the operation frequency from 228 MHz to 263 MHz. At 230 °C, it achieves maximum output power of 1.66 W, the peak gain of 24 dB, peak PAE (power added efficiency) of 25%, OP1dB (output 1-db compression point) of 32 dBm, and OIP3 (output third intercept point) of 37.9 dBm..
Sintered Silver Die Attach with Extreme Thermal Stability for Extreme and Dynamic Environments
Authors: Khtatba Khalid , Paknejad Seyed Amir , Mansourian Ali , Mannan Samjid H.
Published: July 2017

The surface oxidation of internal pore surfaces of nano-scale sintered silver has increased stability for high temperature applications. After treatment, high temperature storage at 400 °C has resulted in no changes to microstructure. By contrast, it is known that the microstructure of untreated pressure-less sintered silver continuously evolves at temperatures above 200 °C. Grain and pore growth occur in this temperature range for conventional sintered silver resulting in coarsening of the microstructure and increased susceptibility to fatigue. However, oxidation treatment of the internal pore surfaces has the effect of freezing the microstructure when the contact metallization is also silver or chemically inert. Oxidation prevents mass transfer by shutting down the fastest atomic migration route along the internal pore surfaces. Samples exhibited no change in microstructure either through continuous observation through glass, or after cross sectioning. The tested specimens under high temperature storage resisted grain growth for the whole duration of the tests of more than 600 h at 300 °C. The only detectable changes in microstructure occurred in a sparse number of isolated grains (1 in 7000 grains), presumably due to non-penetration of oxidising treatment into these closed pore spaces. It is hypothesized that even these can be prevented by minor changes to the sintering paste to slightly increase initial porosity. The oxidising treatment can be performed via many different routes, such as exposure to steam, or even by dipping in water for 10 min.
Time-efficient sintering processes to attach power devices using nanosilver dry film
Authors: Dai Jingru , Li Jianfeng , Agyakwa Pearl , Johnson Christopher Mark
Published: July 2017

Pressure-assisted sintering processes to attach power devices using wet nanosilver pastes with time scales of minutes to a few hours have been widely reported. This paper presents our work on time-efficient sintering, using nanosilver dry film and an automatic die pick and place machine, resulting in process times of just a few seconds. The combined parameters of sintering temperature 250 °C, sintering pressure 10 MPa and sintering time 5 s were selected as the benchmark process to attach 2 mm × 2 mm × 0.5 mm dummy Si devices. Then the effects of either the sintering temperature (240 to 300 °C), time (1 to 9 s) or pressure (6 to 25 MPa) on the porosity and shear strength of the sintered joints were investigated with 3 groups and a total of 13 experimental trials. The average porosities of 24.6 to 46.2% and shear strengths of 26.1 to 47.7 MPa are comparable with and/or even better than those reported for sintered joints using wet nanosilver pastes. Their dependences on the sintering temperature, time and pressure are further fitted to equations similar to those describing the kinetics of sintering processes of powder compacts. The equations obtained can be used to not only reveal different mechanisms dominating the densification and bonding strength, but also anticipate the thermal-induced evolutions of microstructures of these rapidly sintered joints during future reliability tests and/or in service.
Design and fabrication of a power Si/SiC LDMOSFET for high temperature applications
Authors: Li F. , Gammon P.M. , Chan C.W. , Gity F. , Trajkovic T. , Kilchytska V. , Pathirana V. , Ben Ali K. , Flandre D. , Mawby P.A. , Gardner J.W.
Published: July 2017

Power Si/SiC LDMOSFET are being developed for the benefits of high temperature space and terrestrial harsh-environment applications. For the first time, high voltage devices are fabricated on a direct bonded Si/SiC substrate and characterised at room temperature. Peak field-effect channel mobility of the fabricated MOSFET reached ≈300 cm2/V.s and the avalanche breakdown was not observed up to 200 V, despite of a high leakage current in the device off-mode.
A Precision Data Acquisition and Control Platform for 200°C+ High Temperature Environments
Authors: Watson Jeff , Pachchigar Maithil , Bannatyne Ross , Merritt Clay , Conrad Christopher , Smollinger Glenn , Drack Earle
Published: July 2017

In recent years there has been an increasing selection of commercially available electronic components specified for very high temperature (200°C+) operation, driven by the needs of harsh-environment applications such as oil and gas exploration/production, aerospace, heavy industrial, and automotive. However, there remains a significant technical challenge to integrate these components into reliable, high performance systems. In this paper we present a complete reference platform implementation of a precision multichannel sensor data acquisition and control system rated to 200°C. The design offers a complete sensors-to-bits solution using a low power 16-bit, 600kSPS SAR ADC and an ARM® Cortex®-M0 based microcontroller. The signal chain is optimized for precision performance and accurate measurements while maintaining low power and a small footprint. The reference platform is available off the shelf, including hardware design files, processor firmware source code, and PC software for data logging and display, offering design engineers a rapid development tool for prototyping and a faster path to production for even complex harsh-environment applications, reducing design risk and evaluation time.
Evaluation of printed-circuit boards materials for high temperature operation
Authors: Aviño-Salvado Oriol , Sabbah Wissam , Buttay Cyril , Morel Hervé , Bevilacqua Pascal
Published: July 2017

This article presents the long term (1000 h) behaviour of two printed-circuit board materials (Panasonic R1755V, a high-TG glass-epoxy composite and Arlon 85N, a polyimide-based laminate) stored at high temperature (190 °C). Tests are performed in air and in nitrogen atmospheres. Electrical and physical measurements are performed regularly (once per week).

Almost no degradation is observed for both materials, when stored in nitrogen. On the contrary, the board stored in air show the consequences of ageing. This is especially true for the glass-epoxy material, which becomes unusable after 2 weeks, because of large swelling.
The Tamessa project: a practical application of a 225°C multilayer PCB/SMT/COB system
Authors: Tremlett Piers R.
Published: July 2017

The Tamessa project has developed a high-temperature, multilayer, Printed Circuit Board and component assembly process that is capable of withstanding 225°C operating temperatures in a non-hermetic environment. This paper describes the practical application of this project's work to the electronic interface for a high temperature pressure sensor.

The PCB used in Tamessa has been made from novel materials and the Surface Mount Technology (SMT) component attach process is a solder-less process that uses an adhesive. Additionally, the project has developed and proved a Chip on Board (COB) system. The combination has enabled the development of a complete assembly system that has been shown to withstand temperature excursions up to 250°C in a non-hermetic environment. The successful application to a pressure sensor, designed to resist temperatures of 210°C, was a further test to demonstrate its practical capability in a real-life situation.
Effects of Bond Pad Thickness on Shear Strength of Copper Wire Bonds
Authors: Manoharan Subramani , Patel Chandradip , Hunter Stevan , McCluskey Patrick
Published: July 2017

Copper (Cu) wire bonding is now widely accepted as a replacement for gold (Au), however, its use in high reliability applications is limited due to early failures in high temperature and humid conditions. The Au to Cu wire transition is mainly driven by cost savings though there are other advantages to Cu such as better electrical and thermal conductivity, slower intermetallic compound (IMC) formation and reduced wire sweep during transfer molding. Some automotive, industrial and aerospace industries are still reluctant to adopt Cu wire bonded products due to perceived risks of wire and bond pad cracks, the potential for corrosion, and some lack of understanding about its reliability in harsh conditions.

A wire bond is considered good if destructive sampling qualification tests and periodic monitors pass for the batch. Tests include wire pull strength, wire bond shear, IMC coverage, and thickness of bond pad aluminum (Al) remaining beneath the bond. Nondestructive inspections also verify acceptable ball diameter and Al “splash”. This paper focuses on the bond shear test and its contribution to Cu ball bond reliability assessment, especially when changing Al bond pad thickness. A new revision of the JEDEC Wire Bond Shear Test Method, JESD22-B116B, has just been released, to include Cu wirebonds for the first time. It helps to clarify shear test failure modes for Cu ball bonds. However, there are still questions to be answered through research and experimentation, especially to learn the extent to which one may predict Cu ball bond reliability based on shear test results. Pad Al thickness is not considered in the current industry standards for shear test. Yet bond pad Al thickness varies widely among semiconductor products. This research is intended to contribute toward improved industry standards.

In this study, power and time bonding parameters along with bond pad thickness are studied for bond strength. Several wire bonds are created at different conditions, evaluated by optical microscope and SEM, IMC% coverage and bond shear strength. Similar bonding conditions are repeated for bond pads of 4um, 1um and 0.5um thickness.
A Comparison Between Solders & Transient Liquid Phase Sintered Interconnects in High Temperature Multi-Layer Ceramic Capacitors
Authors: Bultitude John , McConnell John , Jones Lonnie , Miller Galen , Magee Jim , Templeton Allen , Gurav Abhijit , Phillips Reggie
Published: July 2017

There is a long-established market for high temperature multi-layer ceramic capacitors (MLCC) that operate at 150°C and higher in down-hole oil & gas exploration, military and aerospace applications. To maximize the capacitance density and achieve a high degree of mechanical robustness, stacks and leaded form factors have been used with High Melting Point (HMP) Pb-containing solders as the preferred interconnects. However, Pb-containing solders are limited to temperatures below 300°C and are banned from many commercial and automotive applications with further legislation limiting their use planned in the future. Common Pb-free solders such as SAC 305 or SnSb alloys are in widespread use but their performance at prolonged exposures at 200°C is limited. Exposures to high reflow temperatures during assembly, especially successive reflow operations, can also compromise interconnect integrity. Higher temperature gold-containing solders are widely available but these are cost prohibitive and so are not viable for emerging high temperature electronics including higher volume, price sensitive Automotive and Power markets. The development of more energy efficient power converters and inverters based on Wide Band Gap (WBG) semiconductors is driving the adoption of higher temperature electronics in these markets since these operate at higher junction temperatures than traditional silicon. This has led to the development of non-solder interconnects based on sintered silver, nano-metal sintering and transient liquid phase sintering (TLPS) technologies capable of higher temperature performance than common solder based interconnects. The availability of discrete components, such as capacitors, that can operate under these conditions is a key barrier to the development and adoption of high temperature electronics. In this paper the key property differences between solders and TLPS interconnect technologies are compared in detail for MLCC interconnects. The development of a new range of nickel Base Metal Electrode C0G MLCC stacks rated for 200°C is described and performance compared to traditional Precious Metal Electrode (PME) stacks. Thermal cycling performance to 200°C of BME X7R stacks made with 10Sn/88Pb/2Ag solders are compared to similar stacks made with TLPS interconnects of Cu-Sn and In-Ag. The development of leadless stacks, a new bulk capacitance form factor enabled by TLPS technology, is described and their properties compared to traditional stacks.
Die-Attach Voiding Reduction in Gold Alloy Solder Preforms
Authors: Leavitt Bernard , Mackie Andy C.
Published: July 2017

The need for high-temperature solders is growing as RF and power semiconductor devices continue to get smaller, with power density increasing both as a consequence of the shrink and as a result of increased power ratings. AuSn20 eutectic solder (Indalloy®182) has been the workhorse for high-temperature, high-reliability, small die-attach applications for many years; however, as junction temperatures (Tj) increase, the gold-tin eutectic is beginning to reach its limit of utility. Higher temperatures cause increased thermal fatigue, and even delamination is seen at the solder joints.

The next option for RF and power semiconductor manufacturers needing these higher temperatures is either AuGe12 (Indalloy®183) or AuSi3.2 (Indalloy®184) eutectic alloy (see Table I).Table 1.Key properties of Au-based eutectic alloys.

Over the years, many customers have tried AuGe12 and the feedback has been that the alloy has poor solderability, which manifests as large voids in the bond. Voids are poor conductors of heat, which create hot spots, and are the primary cause of premature failures.
Polymorphic Ventricular Tachycardia (PMVT) secondary to a combination of azithromycin and fluoxetine in a case of acute pancreatitis
Authors: Gangasani Ashish , Donthireddy Kavitha
Published: July 2017

Polymorphic ventricular tachycardia (PMVT) is characterized by QRS complexes of changing amplitude that appear to twist around the isoelectric line. Torsades de Pointes (Tdp) is a variant of PMVT in which there is prolongation of QTc interval (generally exceeding 500 milliseconds). A number of medications have been noted to prolong the QTc interval. We describe a clinical case in which the culprits are Azithromycin and Fluoxetine. Azithromycin has been regarded as a “safer” macrolide when it comes to proarrhythmia as compared to erythromycin or clarithromycin. However, in certain clinical circumstances like combination drug usage, unique clinical features like underlying pancreatitis in this particular patient, some of the medications that are deemed low risk can certainly be more proarrhythmic. It is therefore important to review the clinical and pharmaceutical profiles of every patient before choosing which medications to prescribe.
Antiviral activity of enviroxime against polio virus and rubella virus in tissue culture
Authors: Al-Khayat Zakarea , Ahmad Abdullatif
Published: July 2017

Enviroxime is an antiviral compound that inhibits the replication of polio and rubella virus. The antiviral activity of this compound was tested in two cell lines (L2OB and RD for poliovirus and HeLa and WISH for Rubellavirus). At a concentration of 32μg/ml or less, the compound is relatively non-toxic to cell lines but has significant antiviral effect. We found the minimal inhibitory concentration (MIC) of 0.06 μg/ml for polio, and 0.125 μg/ml for rubella virus. The therapeutic index (TI) defined as the ratio of the minimal dose of the drug that is toxic to the cells to the dose which inhibit the viral multiplication, is used to evaluate the drug activity. If this index is more than one, the margin of safety for the drug is large. In this study the TI of enviroxime against poliovirus was 54 while it was 14 against Rubella virus. Hence we speculate that this compound if used as an antiviral agent in humans, would have minimal or no side effect.
Effect of sensory motor rhythm neurofeedback on psycho-physiological, electro-encephalographic measures and performance of archery players
Authors: Paul Maman , Ganesan Sathiyaseelan , Sandhu Jaspal , Simon Joel
Published: July 2017

Neurofeedback is an effective tool in sports psychology to train athletes to enhance performance levels. Archery players are required to concentrate on accuracy during archery performances, which tends to be attained by a peak sensory motor rhythm of the electroencephalography component. The selected subjects of university level archery players have intervened with neurofeedback for four weeks. Measurements were taken to find the effect of neurofeedback training (NFT) on heart rate deceleration, precompetition pleasure level, post-competition pleasure level, pre-competition arousal level, post-competition arousal level, performance level, precision, sensory motor rhthm (SMR)/ theta ratio and SMR epoch mean of archers during competition. Statistical analysis reveals that pre-competition pleasure level (p< 0.05), pre-competition arousal level (p< 0.05), post-competition arousal level (p< 0.01) and SMR/ theta ratio (p< 0.05) showed statistically significant changes [deleted after the effective twelve sessions of SMR neurofeedback training] in the experimental group but not the control group. After twelve sessions of NFT training the experimental group archers were able to regulate the psychological status and EEG components during archery performance. The result of the present study suggests that neurofeedback training improves the archery players' regularity in scoring by enhancing accurate arrow shoot attained by controlling and regulating psycho-physiological and electro-encephalographic measures.
Primary central nervous system lymphoma in acquired immunodeficiency syndrome patient
Authors: Namas Rajaie , Olugbemiga Jegede , Shafique Imran , Gebregeorgis Wihib , Hasan Saqib , El Mortada Mohamad , Ege Gurkan , Bachuwa Ghassan
Published: July 2017

Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkins lymphoma of the central nervous system and eye. It is over 1000 times greater in HIV positive than in non-HIV populations. The decline in its incidence since the introduction of the highly active anti-retroviral therapy (HAART) suggests an association of this tumor with severe and prolonged immunosuppression. Clinical presentation results from neurological deficits related to the site of the tumor. Systemic B symptoms are also common. The detection of EBV DNA from the CSF, by nested PCR, is a highly sensitive and specific for HIV-related PCNSL. We present the case of a 31-yearold African American man with medical history significant for AIDS who presented with one-month history of lack of energy and somnolence. CSF appearance was normal. MRI suggested primary CNS lymphomas or toxoplasmosis. CSF EBV DNA by PCR was found to be positive. The clinical presentation of PCNSL is similar to that of toxoplasmosis encephalitis in patients diagnosed with HIV. The initial differentiation between the two pathologies on presentation is important since treatment differs and early treatment has been shown to reduce mortality.
In vivo antiplasmodial activity of byrsocarpus coccineus leaf extract in mice infected with plasmodium berghei
Authors: Akpan Joseph , Akuodor Godwin , Ezeokpo B , Essien A , Bassey A , Ezeonwumelu J.O.C
Published: July 2017

Objective: To investigate the in vivo antiplasmodial activity of ethanolic leaf extract of Byrsocarpus coccineus in mice infected with Plasmodium berghei. Methods: Curative effect against established infection and suppressive activity against early infection were screened. Results: The extract (100,200 and 400 mg/kg, p.o.) has significant (p<0.05) dose dependent activity against the parasites in the curative and suppressive tests. The extract also prolonged the survival time of the infected mice. The oral LD50 values were greater than 5000 mg/kg in mice. Conclusion: The result shows that the extract possesses considerable antiplasmodial activity which can be exploited in malaria therapy.
The reporting of blood and body fluid exposure and follow-up practices in a tertiary care hospital in the United Arab Emirates
Authors: Zaidi Moazzam , Griffiths Robin , Larsen Peter , Newson-Smith Mark , Zaidi Mukarram
Published: July 2017

The study explored the reporting and follow-up practices after blood and body fluid exposures in a tertiary care hospital in the United Arab Emirates. The Occupational Health Clinic schedule was audited, and medical files of staff members visiting the Clinic to report an exposure during 2006 and 2007 were retrieved for a detailed review. The raw data were obtained and analyzed; the original files were used as a reference to recover any missing information. Results showed that 156 exposures were reported; of which 77.6% were needle stick injuries. These were most commonly caused by handling, passing, disposing of needles, or while manipulating the needle in the patient. Hospital Wards were the most common location from which exposures were reported (41%). Nurses reported 61% of the exposures, followed by physicians 24%, laboratory staff 9%, and others 6%. Blood analysis was performed for 63% of patients to whose blood staffs were exposed. Post exposure blood tests were performed on 91% of staff. Treatment and follow-up was traced for 6 months at which 42.3% of the staff did not complete the follow-up. The retrospective clinical audit showed that the reported exposures were not managed properly. Repeated preventable exposures were being reported which involved exposures related to recapping and disposal. We recommend a comprehensive blood and body fluid programme to improve the safety and quality of work at the hospital.
Learning preference among monozygotic twins: An exploratory study
Authors: Binoy Mathew K
Published: July 2017

Students have preferences for how they receive information. The goal of this pilot study was to discover whether there are differences in learning preferences among monozygotic twins doing similar course work while living together. The Visual, Auditory, Reading/writing, Kinesthetic (VARK) scale was used to evaluate learning preference. It was found that there is a marked difference in the learning preference among monozygotic twins. This difference can be attributed to the non-shared environment. An extensive study of this type using a larger sample of monozygotic twins is recommended.
Impact of anthropometric indices on the incidence of low back pain
Authors: Koley Shyamal , Arora Harneet
Published: July 2017

The present study deals with the estimation of nutritional status by four anthropometric indices, viz. Quetelet's index (QI), Oliver's typologic index (OTI), Lorenz's constitutional index (LCI) and muscle index (MI). Subjects were selected from 106 confirmed cases of patients with low back pain (69 females, 37 males, aged 21-76 years) who came to the OPD of Aulakh Bone and Joint Centre, Tarn Taran, Punjab, India. An adequate number of controls (n = 50, 36 female and 14 male) with no prior history of back pain were also included from the same clinic for comparison. A total of fifteen anthropometric characteristics were measured for all subjects to estimate the four anthropometric indices. In findings, gender distribution of chi-square values of four anthropometric indices showed MI and LCI were significantly associated with LBP patients in both sexes QI was found to be statistically significant in female patients only. With age-related chisquare values, MI was significantly associated with female patients of all four age groups but, with male patients, only the younger age group, i.e. 21-30 years. LCI, OTI and QI were significantly associated only with male patients aged 41-50 years, 51+ years, and 21-30 years respectively. Occupation-wise distribution of chi-square values revealed that female patients with working women and housewives were significantly associated with MI but only housewives were significantly associated with LCI. In male patients, MI was significantly associated with the group of others (comprisedof politicians, carpenters, retired employees and labourers), OTI with agricultural workers, and QI with agriculture, businessmen and the group of others. It could be concluded from the present study that, MI and LCI could also be successfully used as the risk indicators of LBP.
Management of common endocrine conditions other than diabetes mellitus during ramadan fasting
Authors: Beshyah Salem , Fiad Tarek , Saadi Hussein
Published: July 2017

Patients with any endocrine condition wishing to observe the fasting during Ramadan may seek advice from their primary care or specialist physician. In healthy people, there are minimal changes in the metabolic and hormonal parameters during fasting. However, management of common endocrine conditions may need some adjustments. Aside from diabetes mellitus, endocrine and metabolic conditions commonly seen in clinical practice include hypothyroidism, hyperthyroidism, adrenal disease, pituitary diseases and obesity. Adjustments in medications are based on physiological and clinical aspects of these conditions, and on sound knowledge of the pharmacological characteristics of all prescribed medications. Thyroid hormones should be taken on an empty (or near empty) stomach and not be followed by food by 0.5-1 hour according to the patient's life style. Glucocorticoids should be taken in the same manner at either end of the fasting period, or changed to an extended release preparation taken on its own or in combination with hydrocortisone with Iftar. Management of hypogonadism is essentially the same both during and outside of Ramadan in both men and women. Growth hormone may be taken in the same manner in both children and adults. Patients with diabetes insipidus should be careful with fluid balance, and take adequate doses of desmopresin in widely spaced dosing for maximum benefit. Spontaneous hypoglycemia may present for the first time during Ramadan, and suggestive symptoms should alert the physician to this diagnosis. Ramadan- type intermittent fasting provides an opportunity for weight loss but this is often lost as evening time feasting seems to offset any benefit from daytime fasting. In conclusion, common endocrine conditions are managed along the same lines of good clinical practice, sound understanding of physiology and pharmacology, coupled with modern approaches of individualized and ethnically competent care.
Update in nephrology and transplantation; 19-20 October 2012; Hilton Hotel, Ras Al Khaimah, United Arab Emirates
Authors: El Essawy Basset
Published: July 2017

These are abstracts of the presentations made during the annual “RAK Update in Nephrology and Transplantation” held on the 19th and 20th of October 2012. Over 2 days, several renowned national, regional and international experts addressed topical issues in clinical nephrology, transplantation and related subjects such as cardiovascular risk, vasculitides and diabetes as they relate to kidney disease. These presentations covered a wide range of subjects addressing the latest basic research findings, clinical trial results and recommendations of the latest clinical practice guidelines. In addition, special attention was paid to adapt the research findings and international clinical practice strategies to local circumstances.
Guidelines for management of type 2 diabetes 2012: Common sense prevails!
Authors: Beshyah Salem , Hassoun Ahmed , Khalil Ali , Saadi Hussein
Published: July 2017

Recently, guidelines on the management of hyperglycemia in type 2 diabetes were released by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD) as their formally adopted position statement. These guidelines are different from the previously published documents. They introduced a nonalgorithmic patient-centered approach that stressed the principles of individualization of care based on several important patients' attributes. They affirmed the role of lifestyle modification as a basic requirement, metformin as the first line pharmacological therapy and individuallytailored basis for the choice of the second and third line drugs. In this paper, the authors reflect on these guidelines from the world-wide practicing physicians' view point.
Estimation of the incidence of pulmonary tuberculosis in Northwestern Libya
Authors: Ben Ramadan Awatef , Shambesh Mohamed , Abusnena Omar , Al-Baccush Mohammad
Published: July 2017

Aim: To estimate the burden of pulmonary tuberculosis (TB) in Libya. Methods: This is a retrospective and descriptive study of pulmonary TB cases gathered from the TB National Center in Tripoli. Results: Pulmonary TB cases represented (50.9%) of total TB cases. The majority of pulmonary TB cases (86.8%) were from five out of twenty one TB Subcenters distributed all over the country, namely (Tripoli, Benghazi, Sebha, Misurata, and Zawia Sub-centers). Estimated incidence & prevalence of total (Libyans and non-Libyans) pulmonary TB cases per 100,000 of total population were (0.08) & (0.09) respectively. Estimated incidence & prevalence of pulmonary TB among Libyans were (0.06 Libyan pulmonary TB cases/ 100,000 of Libyan population), and (0.08 Libyan Pulmonary TB cases/ 100,000 of Libyan population) respectively. Libyans represented (66.6%) of the total number of pulmonary TB cases. Among Libyans the most frequent age group affected was between 25-34 years old (35%) followed by 15-24 years old (21%) and most gender affected was males 70.3% versus females 29.7% (P<0.0001). Immigrant males represented (92%) of non-Libyan cases. The most frequent nationalities among immigrant cases were Sudanese (38%), Chadian (17.6%) and Nigerian (15.3%). Among immigrants; most age group affected was between 25-34 years old (45%) followed by 35-44 years old (32%). Total treatment success rate of pulmonary TB cases was (61.1%), with Libyans exhibiting a higher treatment success rate than their immigrant counterparts (68.1% and 48.6% respectively, P<0.009).
Ionically cross-linked chitosan/tripolyphosphate microparticles for the controlled delivery of pyrimethamine
Authors: Ibezim Emmanuel , Andrade Cristina , Marcia Cristina , Barretto Bianca , Odimegwu Damian , De Lima Felipe
Published: July 2017

Chitosan ionically cross-linked with tripolyphosphate at regulated temperatures (25°C, 40°C, and 50°C) and varying cross-linking times (30 min, 2 h and 4 h respectively) was used to form microparticles employed in the encapsulation of pyrimethamine, an antiprotozoal drug. The yields, equilibrium moisture contents, percentage concentration, swelling characteristics, entrapment efficiency, release properties, infrared spectroscopy, and differential scanning calorimetry of the formulated microparticles were evaluated. The yield of microparticles produced ranged from 0.3515 to 0.7749 g per 100 ml of cross linking solution. The products possessed relatively little amounts of moisture (0.22 − 3.04 % w/v). The entrapment efficiencies ranged from 25.55 to 99 % with the product formed at ambient temperature and cross linking time of 30 min possessing the highest efficiency. The swelling kinetics on the microcapsules revealed that all the products swelled in the various pH media following mainly anomalous sorption mechanism with a few diffusion controlled mechanism. The greatest swellings however occurred at the swelling medium of pH 1 while the least swelling occurred at pH 7. Spectral and differential scanning calorimetric properties of the chitosan used in the study were consistent with those of standard chitosan. The infrared spectroscopy and differential scanning calorimetry of the products confirmed that encapsulation actually occurred with the spectral characters of the products differing from those of the parent constituents (chitosan, tripolyphosphate and pyrimethamine). Based on these factors, tripolyphosphate cross-linked chitosan microparticles present a suitable matrix for the controlled release of pyrimethamine.
Hospitalization patterns of diabetic patients to a tertiary hospital in Abu Dhabi, United Arab Emirates
Authors: Beshyah Salem , Khalil Ali , Benbarka Mahmoud , Mustafa Huda
Published: July 2017

Background: Hospitalization occurs more often in diabetic than non-diabetic patients and is associated with increased morbidity and mortality. Data on these issues are limited in the Middle East, particularly in new nations suffering from a high prevalence of diabetes. Objectives: We studied the contribution of diabetes to the hospital admission rates and evaluated the database- documented causes and outcomes of hospitalization of people with diabetes in a tertiary hospital. Methods and Patients: This was a descriptive, retrospective, electronic records-based study. We identified 14,032 episodes accounted for by diabetes (i.e. 19.1% of the total 51,169 episodes) between 2000-06. Results: 19.1% of admission episodes involved diabetes with an ascending linear trend. The median length of stay was five and four days for diabetes as a primary diagnosis and as a secondary diagnosis respectively. Diabetes as a primary diagnosis was noted in 1,227 patients. The mean age was 42.5 years, and majority were in the 50-70 years age group. Most patients were admitted from the emergency room (71%). Reason for admission was attributed to diabetes per se in >50%, and the majority were discharged home in good condition. On the other hand, diabetes was present as a secondary diagnosis in 8,540 patients (3,494 women and 2,794 Emirati nationals). The mean age of this subgroup was 58.4 years with majority being 41-80 years old. These patients were admitted either as a medical emergency (70%) or directly from home (27%). Patients were admitted under internal medicine (36%), cardiology (27%) and haematology (21%) services. The majority (91%) were discharged home in good condition. A total of 353 patients died while hospitalized (23 with diabetes as a primary diagnosis and 330 when it was a secondary diagnosis respectively. The age at death was 68.8 and 65.4 years in the two subgroups respectively. Conclusions: The present study demonstrated that diabetes is associated with a high number of inpatient episodes. These involved mainly middle-aged adults due to medical and cardiovascular complications of diabetes, and poses a high burden on both health care and the economy.
Lisinopril-induced visceral angioedema in a newly diagnosed hypertensive patient
Authors: Marwan Mohammad , Parmar Chandresh , Jafri Haseeb , Scott Miller
Published: July 2017

We present a 44 year-old female with Angiotensin Converting Enzyme inhibitor-induced visceral angioedema. The patient presented with a short history of diarrhea. Her symptoms resolved with the elimination of lisinoprol. Her Computed tomography finding were reversed too.
Hose Assemblies, Rubber, Hydraulic, Steel Wire Reinforced - Part 1: Procurement Document
Authors:   Hydraulic Hose and Hose Fittings Committee
Published: July 2017

This SAE Standard covers steel wire reinforced rubber hose assemblies using connectors specified in SAE J516 for use in hydraulic systems using petroleum based hydraulic fluids with maximum working pressures of 1.7 to 42 MPa. See Part 2, Table 7 for hose operating temperature ranges and identification codes.

NOTE: Working pressure is defined as maximum system pressure.
Liberty in Jean-Jacques Rousseau: between the Ancient and the Modern
Authors: Barwicka-Tylek Iwona , Pietrzyk-Reeves Dorota
Published: July 2017

Rousseau’s philosophy can be situated as a continuum between the ancient and the modern traditions; we argue that it does not fully belong to either and this is particularly evident in his discussion of liberty. Our point of departure is a view that in order to grasp peculiarity of Rousseaus’ understanding of liberty we need to go beyond the liberal tradition and its scheme of thinking about freedom as well as beyond the intuitive understanding of liberty. The second part of the article presents an analysis of the four different meanings of liberty that we find in Rousseau’s theory: natural, social, moral and civil. The most important for political philosophy is his discussion of the shift from the natural to social and civil liberty and the insistence that true freedom cannot be totally separated from morality. Finally, we discuss some of the contemporary interpretations of Rousseau’s political thought which often emphasize one of the different meanings of liberty that we find in his writings.
En la órbita de Álvaro Siza (o crónica de un encargo imposible)
Authors: Silvestre Navarro Francisco
Published: July 2017

Con motivo de la edición del primer número de la revista en blanco, dedicado a la última producción de D. Álvaro Siza Viera1, tengo ante mí la labor de situar al arquitecto en su contexto. Tarea acogedora por la admiración y el respeto que proceso a D. Álvaro, y sobrecogedora por el respeto y admiración que profeso a su obra. Mucho es lo que ya se ha escrito sobre Siza Viera, mucho de gran profundidad y sobre la base de conocimientos mas sólidos que los míos, mucho lo que aun queda sin duda por escribir y por analizar de una carrera profesional y de una figura en la que sin duda confluyen todos los aspectos necesarios tanto en complejidad como en variedad para que aquellos dispuestos a investigar con seriedad nos entreguen aun conclusiones sorprendentes y resultados reveladores.
La cúpula de la iglesia de San Miguel de Almazán dibujada
Authors: Báez Mezquita Juan Manuel
Published: July 2017

La iglesia de San Miguel de Almazán presenta una cúpula de planta octogonal, compuesta por ocho arcos de medio punto entrelazados en forma de estrella, que denotan influencia islámica. La complejidad constructiva que presenta, así como el trabajo de estereotomía y las intersecciones entre los elementos, no aparecen con claridad en los pocos dibujos que de ella se han realizado, en planta y sección y relativamente pequeños, que no son lo suficientemente explícitos para transmitir su monumentalidad. El autor afronta el reto de dibujarla en perspectiva en gran formato, desde un punto de vista real, dando respuestas a las importantes distorsiones que se producen.
Crítica del análisis geométrico realizado por Ulf Linde acerca de la obra de Marcel Duchamp
Authors: Franco Taboada Manuel
Published: July 2017

El presente estudio pone en cuestión la explicación geométrica dada por Ulf Linde a dos de las obras de Marcel Duchamp (1887-1968), La Mariée (1912) y el Grand Verre (1915-1923), en 1977. En el análisis de la primera de ellas, Linde acierta en el diagnóstico de que la obra responde a unas proporciones áureas, aunque con expresiones matemáticas incorrectas, y en la segunda realiza un análisis poco riguroso, dado que no proporciona las medidas de las que parte para realizarlo. Debido a ello, y como comprobación, realizo el mismo análisis de Linde aplicado al Grand Verre, pero partiendo de las medidas dadas por Duchamp, encontrando que a pesar de ser muy aproximado, no corresponde exactamente a la proporción áurea.
Análisis y generación de cartografías historiográficas en el estudio de la evolución de la forma urbana: el caso de la ciudad de Teruel
Authors: Sancho Mir Miguel , Agustín Hernández Luis , Llopis Verdú Jorge
Published: July 2017

La preocupación por la conservación de las ciudades históricas es un tema recurrente a lo largo de la historia reciente, y, frente a las cambiantes teorías un planteamiento se presenta como irrefutable: la necesidad de conservar la memoria de la ciudad, su pasado, nuestro patrimonio, a través del conocimiento, para que forme parte del saber colectivo y, con ello, perdure en el tiempo. En este contexto se establecen como imprescindibles los estudios sobre la evolución de la morfología urbana.

El presente trabajo tiene como objetivo establecer un marco metodológico válido para el análisis y elaboración de cartografías historiográficas urbanas, como fase fundamental en los estudios sobre la evolución de la forma urbana, mediante su aplicación al caso de la ciudad de Teruel. Gracias a ello, se ha constatado la importancia de seguir un riguroso proceso gráfico con el que poder evaluar la precisión de la documentación utilizada, posible gracias al empleo de los Sistemas de Información Geográfica.
Transexualidades: os rostos do estigma e da exclusão social
Authors: Caravaca Morera Jaime Alonso , Padilha Maria Itayra
Published: July 2017

http://dx.doi.org/10.5007/1806-5023.2016v13n1p120Esta reflexão tem por objetivo analisar as diferentes manifestações do estigma e da exclusão social entre a população transexual. As diferentes expressões da transexualidade na contemporaneidade têm sido influenciadas pelos diversos dispositivos de controle heterocisnormativo oriundos do patriarcalismo. Evidencia-se que a exclusão social e a estigmatização possuem diferentes faces e componentes, tais como: aspectos pessoais, cognitivos, emocionais, estruturais e comportamentais, que emergem como consequência direta da implantação da ideologia psiquiatrizante e patologizante da condição transexual e das outras manifestações da corporeidade e sexualidade relativas à concepção ontológica dos sujeitos.
O chinelo rosa: corpo e gênero na educação infantil
Authors: Krug Camila De Fátima , Rodrigues Soares Rosângela De Fátima
Published: July 2017

Trata-se do relato de uma pesquisa realizada em uma creche pública localizada no munícipio de Porto Alegre-RS. Tal pesquisa foi realizada em uma abordagem qualitativa numa perspectiva cultural dos conceitos de corpo e gênero, com delineamento de estudo de caso. As análises estão ancoradas nesta perspectiva, a partir da reflexão sobre cenas observadas e selecionadas na rotina de sala de uma turma de Maternal 2. Os resultados obtidos apontam que as representações dos marcadores de gênero atribuídos ao feminino e masculino em nossa sociedade se entrecruzam com o pedagógico, impedindo em alguns momentos as crianças de participar das atividades, como na exploração de materiais de cunho artístico, e em outros, impelindo suas participações, como no exemplo das fantasias. Pretende-se assim, que os apontamentos feitos com a pesquisa possam contribuir para a reflexão sobre as conexões entre corpo e gênero na educação infantil, e a atuação docente.