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Rheumatoid arthritis is a persistent autoimmune disorder that causes both systemic and local inflammation. Several proinflammatory cytokines, such as interleukin (17A )and interleukin (21), genetic variation, and environmental variables induce it. The purpose of this study is to examine IL-17A (rs2275913) G/A and IL-21 (rs4833837) C/T gene polymorphism association in Iraqi patients with rheumatoid arthritis. The current study includes 120 subjects classified into two main groups: 60 RA patients and 60 healthy controls. Tetra ARMS- PCR and Allele-specific PCR were used for the detection of IL-17A and IL-21 gene polymorphisms respectively. Genotype and allele frequency results of IL17 rs2275913 G/A and IL-21 rs4833837 C/T gene polymorphisms were analyzed under codominant, dominant, recessive, and additive models. IL17A (rs2275913) G/A under codominant pattern with heterozygous genotype (G/A) and dominant pattern, those of the GA+AA genotypes significantly higher in RA patients with respect to those of the control group (OR:3.3, CI 95%: ( 1.11 to 9.96), P< 0.03) and (OR: 3.35, CI 95%: ( 1.12 to 9.99), P< 0.03) respectively. In addition, this genetic polymorphism doesn't appear significant variation in other inheritance models. The allele (A) frequency was observed to be higher in RA patients (49%) opposite the allele (G) frequency observed to be higher in control (59%) without significant variation between them, On the other hand, IL-21 rs4833837 C/T genotyping and allele frequencies results revealed no significant variation between the rheumatoid arthritis patients in comparison with the control groups. [ABSTRACT FROM AUTHOR]

Background: Hemoglobin can develop abnormally as a result of hereditary blood illnesses called thalassemia that are inherited from a person's parents. Objective: The goal of this study was to identify the tumor necrosis factor alpha (TNF-a) A/G polymorphism and correlate TNF-a serum levels with illness progression. Patients and Methods: Eighty cases with beta-thalassemia who had been diagnosed at the thalassemia center at Al-Zahra Hospital in Al-Najaf province, Iraq participated in a case-control study with 40 healthy individuals serving as the control group. The 80 individuals were divided based on HCV status. From 50 seropositive hepatitis C virus (HCV) patients, 19 had IgG positivity, 15 had IgM positivity, and 16 had both IgG and IgM positivity. All patients and the control group had blood samples taken. DNA from blood was taken to be utilized in PCR to find the TNF-a A/G polymorphism. TNF-a levels were assessed using an ELISA test. Results: The findings explained why HCV-infected individuals had high significant rates of thalassemia than noninfected ones. The findings showed that in thalassemia patients, AA genotype and A allele are risk factors for severity, whereas GG genotype and G allele are protective factors for severity. Conclusions: The findings showed that having an AA genotype increases your chance of contracting HCV. This study also demonstrated a considerably higher level of TNF-a in thalassemia patients compared to controls, as well as a significantly higher level of TNF-a in thalassemia patients who also had HCV infection compared to controls and patients without HCV infection. [ABSTRACT FROM AUTHOR]

In the current study, nontoxic selenium nanoparticles were produced extracellularly utilizing probiotic Bacillus clausii bacteria, and their antibacterial efficacy against multidrug-resistant bacteria was evaluated .Initially, the biosynthesis of SeNPs was indicated by the transformation of the reaction mixture from yellow to dark red. UV-Visible spectrophotometry was used to characterize biosynthetic nanoparticles, and the greatest absorbance peak of nanoparticles was recorded at wave lengths of (270nm). Nanoparticle size, shape, and distribution were all detected using a scanning electron microscope (SEM). The nanoparticles had a spherical, homogeneous shape, and their sizes ranged from (40-150nm). Energy Dispersive-x-ray Spectroscopy (EDS) investigation of the presence of elemental selenium.. Biosynthesized AgNPs exhibited antibacterial activity against the majority of multidrug-resistant bacteria (MDR), such as Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumonia, Acinetobacter baumannii, Proteus mirabilis, pseudomonas aeruginosa, and Shigella sonii, when compared to the results of an antibiotic disc of Ceftriaxone, Azithromycin,Cefepime, Amikacin, Meropenem,Oxacillin, Gentamicin and Ciprofloxacin against such clinical bacteria. According to the findings, probiotics and SeNPs will be used to enhance or replacement of antibiotics. [ABSTRACT FROM AUTHOR]

Cheyletus malaccensis Oudemans (Acari: Cheyletidae) was the most abundant species among predatory mites in stored product samples collected from Hail region, Saudi Arabia during the period 2015-2016. This mite was provided with the acarid mite, Tyrophagus putrescentiae (Schrank) as a food source and incubated at 20, 25, 30 and 35oC and 65% RH. Influence of the four temperatures was evaluated on survival, development and reproduction of C. malaccensis. Results showed that fecundity, net reproductive rate (Ro), intrinsic rate of increase (rm) and finite rate of increase (erm) significantly increased by increasing temperatures. Nevertheless, incubation period, developmental time, duration of life span, mean generation time (T) and doubling time (DT) were negatively correlated with temperature increase. Temperatures of 25 and 30oC were the most suitable conditions to obtain the greatest population of C. malaccensis in a short time. C. malaccensis proved to be effective and can play a considerable role in biological control of stored-product insect and mite pests. [ABSTRACT FROM AUTHOR]

The paper is a mini review on the authors own work related to laser induced processes at metal nanoparticle/oxidic support systems. A number of aspects will be addressed ranging from the nano particle size dependence on the efficiency of the photochemical process, the influence of low coordination sites of the nano particles and dynamical processes such as energy transfer between adsorbates, light induced particle changes or spill over processes. The paper reviews nano and femtosecond laser experiments as well as quantum state resolved experiments. Results will be compared to typical findings from simple oxidic supports and metal single crystals. This review may be of interest for future photocatalyst development for applications such as solar fuel synthesis and related problems. [ABSTRACT FROM AUTHOR]

Multiphoton microscopy of cellular autofluorescence and second harmonic generation from collagen facilitates imaging of living cells and tissues without the need for additional fluorescent labels. Here, a compact multiphoton endomicroscope for label‐free in vivo imaging in small animals via side‐viewing needle objectives is presented. Minimal invasive imaging at cellular resolution is performed in colonoscopy of mice without surgical measures and without fluorescent dyes as a contrast agent. The colon mucosa is imaged repeatedly in the same animal in a mouse model of acute intestinal inflammation to study the process of inflammation at the tissue level within a time period of ten days, demonstrating the capabilities of label‐free endomicroscopy for longitudinal studies for the first time. [ABSTRACT FROM AUTHOR]

The predatory mites, Neoseiulus cucumeris (Oud.) and Neoseiulusbarkeri (Hughes) (Acari: Phytoseiidae), were collected from leaves of the kidney bean (Phaseolus vulgaris L.) growing at Hail District, Saudi Arabia, in 2017. Different biological aspects and life table parameters of both predators were evaluated by feeding on three insect egg species, Anagasta (Ephestia) kuehniella (Keller) (Pyralidae), Sitotroga cerealella (Oliv.) (Gelechiidae), and Spodoptera littoralis (Boisduval) (Noctuidae), as alternative food sources at 27 °C and 70% RH. Predators’ developmental times were affected by food type. Duration of life cycle was significantly longer when N. cucumeris was provided with S. cerealella eggs (16.56 days for male and 15.42 days for female) than the other two kinds of insect eggs. Maximum time of life cycle of N. barkeri occurred for male fed on eggs of S. cerealela (18.82 days), likewise the minimum time was observed for male fed on eggs of A. kuehniella (9.92 days).The fecundity of both phytoseiid mites was the highest (25.06 eggs/♀, with a daily rate of 2.05 eggs/♀/day, for N. cucumeris and 23.26 eggs/♀, with a daily rate of 2.04 eggs/♀/day, for N. barkeri, respectively) by feeding on eggs of A. kuehniella. Fecundity was the lowest (13.37 eggs/♀, with a daily rate of 1.48 eggs /♀/ day and 10.35 eggs/♀, with a daily rate of 0.84 eggs/♀/day for the two predatory mites, respectively) on S. cerealella eggs. Food source affected all the life table parameters of both tested predatory mites. It was concluded that two phytoseiid mite species can be maintained successfully on the alternative food, A. kuehniella eggs, in lab trials whenever the natural prey types are scarce. [ABSTRACT FROM AUTHOR]

Abstract: We describe the optical pump–probe laser system at the XUV free-electron laser FLASH at DESY. A growing interest in optical laser pulses combined with the free-electron laser (FEL) beam for time-resolved experiments raise high demands on the stability of operation and knowledge on the status of synchronization between the XUV and optical pulses. In this publication we describe this system, the characterization of the optical pulses, synchronization and timing schemes as well as beamlines that transport beam to experimental stations. [Copyright &y& Elsevier]

In this Letter, we present a simple approach for monitoring electron bunch form and arrival time combining electro-optic sampling and phase and frequency sensitive signal detection. The sensitivity of the technique has the potential to allow online diagnostics to be performed down to bunch charges in the femto coulomb regime. The concept has high impact for the developments of the next generation of 4th generation x-ray light sources working with long pulse trains or continuous wave mode of operation. [ABSTRACT FROM AUTHOR]

The free-electron laser (FEL) sources FLASH in Hamburg, LCLS at Stanford, and FERMI in Trieste provide XUV to soft X-ray radiation (FLASH and FERMI) or soft to hard X-ray radiation (LCLS) with unprecedented parameters in terms of ultrashort pulse length, high photon flux, and coherence. These properties make FELs ideal tools for studying ultrafast dynamics in matter on a previously unaccessible level. This paper first reviews results obtained at FEL sources during the last few years in the field of magnetism research. We start with pioneering experiments at FLASH demonstrating the feasibility of magnetic scattering at FELs [1, 2], then present pump–probe scattering experiments [3, 4] as well as the first FEL magnetic imaging experiments [5], and finally discuss a limitation of the scattering methods due to a quenching of the magnetic scattering signal by high-fluence FEL pulses [6]. All of the presented experiments exploit the X-ray magnetic circular dichroism effect [7, 8] to obtain element-specific magnetic scattering contrast, as known from synchrotron experiments [9–12]. [ABSTRACT FROM PUBLISHER]

The dissociation dynamics induced by a 100 fs, 400 nm laser pulse in a rotationally cold Br2 sample was characterized by Coulomb explosion imaging (CEI) using a time-delayed extreme ultra-violet (XUV) FEL pulse, obtained from the Free electron LASer in Hamburg (FLASH). The momentum distribution of atomic fragments resulting from the 400 nm-induced dissociation was measured with a velocity map imaging spectrometer and used to monitor the internuclear distance as the molecule dissociated. By employing the simultaneously recorded in-house timing electro-optical sampling data, the time resolution of the final results could be improved to 300 fs, compared to the inherent 500 fs time-jitter of the FEL pulse. Before dissociation, the Br2 molecules were transiently 'fixed in space' using laser-induced alignment. In addition, similar alignment techniques were used on CO2 molecules to allow the measurement of the photoelectron angular distribution (PAD) directly in the molecular frame (MF). Our results on MFPADs in aligned CO2 molecules, together with our investigation of the dissociation dynamics of the Br2 molecules with CEI, show that information about the evolving molecular structure and electronic geometry can be retrieved from such experiments, therefore paving the way towards the study of complex non-adiabatic dynamics in molecules through XUV time-resolved photoion and photoelectron spectroscopy. [ABSTRACT FROM AUTHOR]

We present results of single-shot resonant magnetic scattering experiments of Co/Pt multilayer systems using 100 fs long ultraintense pulses from an extreme ultraviolet (XUV) free-electron laser. An x-ray-induced breakdown of the resonant magnetic scattering channel during the pulse duration is observed at fluences of 5 J/cm2. Simultaneously, the speckle contrast of the high-fluence scattering pattern is significantly reduced. We performed simulations of the nonequilibrium evolution of the Co/Pt multilayer system during the XUV pulse duration. We find that the electronic state of the sample is strongly perturbed during the first few femtoseconds of exposure leading to an ultrafast quenching of the resonant magnetic scattering mechanism. [ABSTRACT FROM AUTHOR]

We present a time-resolved infrared (IR) pump and extreme-ultraviolet (XUV) probe diffraction experiment to investigate ultrafast structural dynamics in colloidal crystals with picosecond resolution. The experiment was performed at the FLASH facility at DESY with a fundamental wavelength of 8 nm. In our experiment, the temporal changes of Bragg peaks were analyzed, and their frequency components were calculated using Fourier analysis. Periodic modulations in the colloidal crystal were localized at a frequency of about 4-5 GHz. Based on the Lamb theory, theoretical calculations of vibrations of the isotropic elastic polystyrene spheres of 400 nm in size reveal a 5.07-GHz eigenfrequency of the ground (breathing) mode. [ABSTRACT FROM AUTHOR]

Surprisingly, if a ferromagnet is exposed to an ultrafast laser pulse, its apparent magnetization is reduced within less than a picosecond. Up to now, the total magnetization, i.e., the average spin polarization of the whole valence band, was not detectable on a sub-picosecond time scale. Here, we present experimental data, confirming the ultrafast reduction of the total magnetization. Soft x-ray pulses from the free electron laser in Hamburg (FLASH) extract polarized cascade photoelectrons from an iron layer excited by a femtosecond laser pulse. The spin polarization of the emitted electrons is detected by a Mott spin polarimeter. [ABSTRACT FROM AUTHOR]

Time delays for atomic photoemission obtained in streaking or reconstruction of attosecond bursts by interference of two-photon transitions experiments originate from a combination of the quantum mechanical Wigner time and the Coulomb-laser coupling. While the former was investigated intensively theoretically as well as experimentally, the latter attracted less interest in experiments and has mostly been subject to calculations. Here, we present a measurement of the Coulomb-laser coupling-induced time shifts in photoionization of neon at 59.4 eV using a terahertz (THz) streaking field (λ=152 μm). Employing a reaction microscope at the THz beamline of the free-electron laser in Hamburg (FLASH), we have measured relative time shifts of up to 70 fs between the emission of 2p photoelectrons (∼38 eV) and low-energetic (<1 eV) photoelectrons. A comparison with theoretical predictions on Coulomb-laser coupling reveals reasonably good agreement. [ABSTRACT FROM AUTHOR]

Irradiation of nanoscale clusters and large molecules with intense laser pulses transforms them into highly-excited non- equilibrium states. The dynamics of intense laser-cluster interaction is encoded in electron kinetic energy spectra, which contain signatures of direct photoelectron emission as well as emission of thermalized nanoplasma electrons. In this work we report on a so far not observed spectrally narrow bound state signature in the electron kinetic energy spectra from mixed Xe core - Ar shell clusters ionized by intense extreme-ultraviolet (XUV) pulses from a free-electron-laser. This signature is attributed to the correlated electronic decay (CED) process, in which an excited atom relaxes and the excess energy is used to ionize the same or another excited atom or a nanoplasma electron. By applying the terahertz field streaking principle we demonstrate that CED-electrons are emitted at least a few picoseconds after the ionizing XUV pulse has ended. Following the recent finding of CED in clusters ionized by intense near-infrared laser pulses, our observation of CED in the XUV range suggests that this process is of general relevance for the relaxation dynamics in laser produced nanoplasmas. [ABSTRACT FROM AUTHOR]