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Flavonoids are natural compounds derived from different types of vegetables, fruits, and medicinal herbal plants. Hesperidin, a flavanone (a class of flavonoids) glycoside is found abundantly in citrus fruits such as oranges, lemons tangerines and limes and is known to possess significant benefits, such as anti-inflammatory, anti-stress, antioxidant, growth promoting, anticancer and immunological properties. Hesperidin enhances mucosal and humoral immunity by increasing intestinal intraepithelial lymphocyte numbers, lymphoid organs (thymus, spleen and bursa) indices, as well as improving anti-avian influenza and anti-Newcastle disease antibody titres in poultry. In addition, hesperidin is a strong chain-breaking antioxidant that provides potent cellular antioxidant defence against the damaging effects induced by peroxide hydrogen. As a natural antioxidant, hesperidin could help mitigate heat stress during summer by decreasing heterophil-to-lymphocyte ratios, and quenching reactive oxygen species generated by summer heat stress. The aim of this review was to elucidate the biological effects and health benefits of hesperidin as an alternative of synthetic immune boosters and growth promoters in poultry diets.

This is the official guideline endorsed by the specialty associations involved in the care of head and neck cancer patients in the UK. The anaesthetic considerations for head and neck cancer surgery are especially challenging given the high burden of concurrent comorbidity in this patient group and the need to share the airway with the surgical team. This paper provides recommendations on the anaesthetic considerations during surgery for head and neck cancer.

The poultry sector is an important and vibrant segment of agriculture in Pakistan with a significant contribution to the national GDP (1.3%). Commercial poultry production in Pakistan started in the 1960's and has been providing a significant portion of daily proteins to the Pakistani population ever since. During its evolution the industry enjoyed promotional policies of the Government, but has faced several challenges such as disease outbreaks and retail price fluctuations. Despite its important role in the country's economy, not a single scientific study is available on its evolutionary history. The data available in this regard are scattered and lack reliability. This review is an effort to encompass the history of the overall growth of the poultry industry in Pakistan, its present status (2012 statistics) and future directions and challenges. This article may serve as the basic source of information on Pakistan's poultry industry achievements. It will also guide poultry experts and policy makers for developing strategic planning for further growth of the industry.

This paper concerns with the unsteady MHD flow of a second grade fluid between two parallel walls through porous media induced by rectified sine pulses shear stress. The analytical expressions for the velocity field and the adequate shear stress are determined by means of the Laplace transform technique and Fourier cosine and sine transforms and are written as a sum of steady state and transient solutions. The influence of side walls on the fluid motion, the distance between walls for which the velocity of the fluid in the middle of the channel is negligible, and the required time to reach the steady state are presented by graphical illustrations. As the second grade fluid parameter → 0 the problem reduces to the Newtonian fluids performing the same motion.

Silicon (Si) nanowires offer great potential for field ionization (FI) applications due to well-established Si microfabrication methods combined with favorable ionizing properties of Si. Band bending of semiconductors under applied electric fields increases the FI probability, which is not possible with metal-based counterparts. While it has been demonstrated that scaling down the active material geometry can increase the FI efficiency, maximum electric field at the tip of a single nanowire decreases by quenching effect of nearby nanowires. In this work, optimization of Si nanowire geometries for improved FI efficiencies is explored.

Newcastle Disease (ND) is regarded as one of the major diseases of poultry because of the devastating losses that the virulent form of the ND virus can impose on both commercial and domestic chickens. However, the disease can be controlled through the administration of effective vaccines. Almost all the commercially available ND vaccines require refrigeration and begin to deteriorate rapidly after 1-2 hours if left at room temperature (around 25°C). Subsequently, because maintaining an adequate supply of refrigerated facilities may be a difficult task in many countries with unreliable electrical supplies, the development and large scale production of an effective thermostable ND vaccine seems imperative to support the poultry industry. Such vaccines should be resilient to damage associated with either very cold or hot environments so there are no concerns about the viability of the vaccine in response to temperatures fluctuations that can occur in extreme environments when the difference in temperature during cold and warm seasons can vary greatly. In the following review paper, the development of such a vaccine is discussed, including molecular characterisation, organ tropism of vaccine strains, production, as well as administration methods and their efficacy. It addition, the potential payback has been calculated alongside opportunities provided by removing vaccines from cold chain storage.

The mechanisms involved in the formation of titanium (Ti) nanoclusters produced by sputtering and inert gas condensation were investigated experimentally and numerically. Ti nanoclusters were generated inside an ultrahigh vacuum compatible system under different source parameters, i.e., inert gas flow rate (fAr), length of the aggregation region (L), and sputtering discharge power (P). Nanocluster size and yield were measured using a quadrupole mass filter (QMF). The variation of the above source parameters enabled fine-tuning of the nanocluster size and yield. Herein, Ti nanoclusters were produced within the size range 3.0–10.0 nm. The combination between the nanocluster size and yield as a function of source parameters enabled understanding Ti nanocluster formation mechanisms, i.e., three-body and two-body collisions. The results show that two-body collisions dominate nanocluster production at low fAr while the three-body collisions dominate at high fAr. In addition, nanocluster size increases as L increases due to the increase in nanocluster nucleation and growth times. The maximum nanocluster yield was obtained at fAr that maximize the probability of three-body and two-body collisions. Nanoclusters could be produced within an optimum range of the sputtering discharge power wherein the nanocluster size and yield increase with increasing the discharge power as a result of increasing the amount of sputtered material. The experimental results were compared with a theoretical model of nanocluster formation via three-body collision. Detailed understanding of the evolution of size and yield of Ti (and Ti-oxide) nanoclusters is essential for producing nanoclusters that can be utilized for environmental applications such as conversion of carbon dioxide and water vapor into hydrocarbons.

The Ultra-Fast Flash Observatory (UFFO) is a space observatory for optical follow-ups of gamma ray bursts (GRBs), aiming to explore the first 60 seconds of GRBs optical emission. UFFO is utilized to catch early optical emissions from GRBs within few sec after trigger using a Gimbal mirror which redirects the optical path rather than slewing entire spacecraft. We have developed a 15 cm two-axis Gimbal mirror stage for the UFFO-Pathfinder which is going to be on board the Lomonosov satellite which is to be launched in 2013. The stage is designed for fast and accurate motion with given budgets of 3 kg of mass and 3 Watt of power. By employing stepping motors, the slewing mirror can rotate faster than 15 deg/sec so that objects in the UFFO coverage (60 deg × 60 deg) can be targeted in ~1 sec. The obtained targeting resolution is better 2 arcmin using a close-loop control with high precision rotary encoder. In this presentation, we will discuss details of design, manufacturing, space qualification tests, as well as performance tests.

The UFFO (Ultra-Fast Flash Observatory) is a GRB detector on board the Lomonosov satellite, to be launched in 2013. The GRB trigger is provided by an X-ray detector, called UBAT (UFFO Burst Alarm & Trigger Telescope), which detects X-rays from the GRB and then triggers to determine the direction of the GRB and then alerts the Slewing Mirror Telescope (SMT) to turn in the direction of the GRB and record the optical photon fluxes. This report details the calibration of the two components: the MAPMTs and the YSO crystals and simulations of the UBAT. The results shows that this design can observe a GRB within a field of view of ±35° and can trigger in a time scale as short as 0.2 – 1.0 s after the appearance of a GRB X-ray spike.

The Ultra-Fast Flash Observatory (UFFO) aims to detect the earliest moment of Gamma-Ray Bursts (GRBs) which is not well known, resulting into the enhancement of GRB mechanism understanding. The pathfinder mission was proposed to be a scaled-down version of UFFO, and only contains the UFFO Burst Alert & Trigger Telescope (UBAT) measuring the X-ray/gamma-ray with the wide-field of view and the Slewing Mirror Telescope (SMT) with a rapid-response for the UV/optical photons. Once the UBAT detects a GRB candidate with the position accuracy of 10 arcmin, the SMT steers the UV/optical photons from the candidate to the telescope by the fast rotatable mirror and provides the early UV/optical photons measurements with 4 arcsec accuracy. The SMT has a modified Ritchey-Chrètien telescope with the aperture size of 10 cm diameter including the rotatable mirror and the image readout by the intensified charge-coupled device. There is a key board called the UFFO Data Acquisition system (UDAQ) that manages the communication of each telescope and also of the satellite and the UFFO overall operation. This pathfinder is designed and built within the limited size and weight of  ~20 kg and the low power consumption up to  ~30 W. We will discuss the design and performance of the UFFO-pathfinder, and its integration to the Lomonosov satellite.

The Ultra-Fast Flash Observatory (UFFO) Pathfinder for Gamma-Ray Bursts (GRBs) consists of two telescopes. The UFFO Burst Alert & Trigger Telescope (UBAT) handles the detection and localization of GRBs, and the Slewing Mirror Telescope (SMT) conducts the measurement of the UV/optical afterglow. UBAT is equipped with an X-ray detector, analog and digital signal readout electronics that detects X-rays from GRBs and determines the location. SMT is equipped with a stepping motor and the associated electronics to rotate the slewing mirror targeting the GRBs identified by UBAT. First the slewing mirror points to a GRB, then SMT obtains the optical image of the GRB using the intensified CCD and its readout electronics. The UFFO Data Acquisition system (UDAQ) is responsible for the overall function and operation of the observatory and the communication with the satellite main processor. In this paper we present the design and implementation of the electronics of UBAT and SMT as well as the architecture and implementation of UDAQ.

The Ultra-Fast Flash Observatory (UFFO), which will be launched onboard the Lomonosov spacecraft, contains two crucial instruments: UFFO Burst Alert & Trigger Telescope (UBAT) for detection and localization of Gamma-Ray Bursts (GRBs) and the fast-response Slewing Mirror Telescope (SMT) designed for the observation of the prompt optical/UV counterparts. Here we discuss the in-space calibrations of the UBAT detector and SMT telescope. After the launch, the observations of the standard X-ray sources such as pulsar in Crab nebula will provide data for necessary calibrations of UBAT. Several standard stars will be used for the photometric calibration of SMT. The celestial X-ray sources, e.g. X-ray binaries with bright optical sources in their close angular vicinity will serve for the cross-calibration of UBAT and SMT.

One of the unexplored domains in the study of gamma-ray bursts (GRBs) is the early time phase of the optical light curve. We have proposed Ultra-Fast Flash Observatory (UFFO) to address this question through extraordinary opportunities presented by a series of small space missions. The UFFO is equipped with a fast-response Slewing Mirror Telescope that uses a rapidly moving mirror or mirror array to redirect the optical beam rather than slewing the entire spacecraft or telescope to aim the optical instrument at the GRB position. The UFFO will probe the early optical rise of GRBs with sub-second response, for the first time, opening a completely new frontier in GRB and transient studies. Its fast response measurements of the optical emission of dozens of GRB each year will provide unique probes of the burst mechanism and test the prospect of GRB as a new standard candle, potentially opening up the z > 10 universe. We describe the current limit in early photon measurements, the aspects of early photon physics, our soon-to-be-launched UFFO-pathfinder mission, and our next planned mission, the UFFO-100.

The effect of argon concentration (10%–40%) on the surface properties of molybdenum is studied in nitrogen-argon mixture using 100 Hz pulsed dc glow discharge. The analysis is carried out by using X-ray diffractometer (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and Vickers microhardness tester to investigate surface properties of the nitrided samples. XRD results exhibit the formation of molybdenum nitrides. Crystallite size analysis and SEM morphology confirm the growth of nanostructured molybdenum nitride layers. Moreover, significant increase in surface hardness (by a factor of about two times) is found when the sample is treated for 30% argon in nitrogen-argon mixed plasma.

Copper–tin (CuxSn1−x) nanocluster is a promising system for gas sensing applications, mainly because of its sensitivity and selectivity for H2S. In this work, pure Sn and Cu as well as composite CuxSn1−x nanoclusters were synthesized using the dc magnetron sputtering gas condensation technique. Nanoclusters with different Sn to Cu ratios were produced by changing the ratio of Sn and Cu in the target. The dependence of Sn, Cu, and CuxSn1−x nanoclusters’ size distribution on various source parameters, such as the inert gas flow rate and aggregation length, has been investigated in detail. The results show that as the inert gas flow rate increases, the mean nanocluster size increases for Sn, decreases for Cu, while increases and then decreases for CuxSn1−x. The results could be understood in terms of the contribution percentage of the nanocluster formation mechanism. Furthermore, this work demonstrates the ability of tuning the CuxSn1−x nanoclusters’ size and composition by a proper optimization of the source operation conditions.