bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrasensitive analysis of genetic instability related to chemical exposure
Authors: Domoradzki Tomasz , Grochowski Piotr , Jaśkiewicz Anna , Pająk Beata
Published: December 2021

Our concerns have been raised about whether prolonged exposure to ammunition-related chemicals could correlate with genomic instability predisposing to lung carcinogenesis. The group of professional soldiers engaged in routine ammunition analysis and its explosive properties testing. To assess the presence of an innate genetic profile, DNA isolated from swabs was analyzed with LungCarta and HS Lung Panels and MassARRAY Analyzer 4 mass spectrometry. The presence of new somatic single nucleotide polymorphisms (SNPs) was detected with liquid biopsy technique and circulating cell-free DNA (ccfDNA) isolation, which was further analyzed with UltraSeek Lung Panel. Both genetic profiles obtained for each individual were compared. Genetic analysis revealed that in professional soldiers with long-term exposure to ammunition-related toxic chemicals, new SNPs in genes related to lung carcinogenesis are present. The preliminary data indicate that using modern molecular techniques could be a valuable tool for monitoring the genome instability in context of occupational risk of harmful volatile toxic compounds and improving personnel safety. The analyzed group will be further enlarged, and follow-up studies will be continued.
WHY STUDYING THE HISTORY OF PHILOSOPHY MATTERS
Authors: Marmodoro Anna
Published: December 2021

The debate over whether and how philosophers of today may usefully engage with philosophers of the past is nearly as old as the history of philosophy itself. Does the study of the history of philosophy train or corrupt the budding philosopher's mind?Whystudy the history of philosophy? And,howto study the history of philosophy? I discuss some mainstream approaches to the study of the history of philosophy (with special focus on ancient philosophy), before explicating the one I adopt and commend.
Diffusion tensor imaging in unclear intramedullary tumor-suspected lesions allows separating tumors from inflammation
Authors: Hohenhaus Marc , Merz Yorn , Klingler Jan-Helge , Scholz Christoph , Hubbe Ulrich , Beck Jürgen , Wolf Katharina , Egger Karl , Reisert Marco , Kremers Nico
Published: December 2021

Design

Prospective diagnostic study.

Objectives

Primary imaging-based diagnosis of spinal cord tumor-suspected lesions is often challenging. The identification of the definite entity is crucial for dedicated treatment and therefore reduction of morbidity. The aim of this trial was to investigate specific quantitative signal patterns to differentiate unclear intramedullary tumor-suspected lesions based on diffusion tensor imaging (DTI).

Setting

Medical Center - University of Freiburg, Germany.

Methods

Forty patients with an unclear tumor-suspected lesion of the spinal cord prospectively underwent DTI. Primary diagnosis was determined by histological or clinical work-up or remained indeterminate with follow-up. DTI metrics (FA/ADC) were evaluated at the central lesion area, lesion margin, edema, and normal spinal cord and compared between different diagnostic groups (ependymomas, other spinal cord tumors, inflammations).

Results

Mean DTI metrics for all spinal cord tumors (n = 18) showed significantly reduced FA and increased ADC values compared to inflammatory lesions (n = 8) at the lesion margin (p < 0.001, p = 0.001) and reduced FA at the central lesion area (p < 0.001). There were no significant differences comparing the neoplastic subgroups of ependymomas (n = 10) and other spinal cord tumors (n = 8), but remaining differences for both compared to the inflammation subgroup. We found significant higher ADC (p = 0.040) and a trend to decreased FA (p = 0.081) for ependymomas compared to inflammations at the edema.

Conclusion

Even if distinct differentiation of ependymomas from other spinal cord neoplasms was not possible based on quantitative DTI metrics, FA and ADC were feasible to separate inflammatory lesions. This may avoid unnecessary surgery in patients with unclear intramedullary tumor-suspected lesions.
Mathematical modelling of SARS-CoV-2 variant outbreaks reveals their probability of extinction
Authors: Schiøler Henrik , Knudsen Torben , Brøndum Rasmus Froberg , Stoustrup Jakob , Bøgsted Martin
Published: December 2021

When a virus spreads, it may mutate into, e.g., vaccine resistant or fast spreading lineages, as was the case for the Danish Cluster-5 mink variant (belonging to the B.1.1.298 lineage), the British B.1.1.7 lineage, and the South African B.1.351 lineage of the SARS-CoV-2 virus. A way to handle such spreads is through a containment strategy, where the population in the affected area is isolated until the spread has been stopped. Under such circumstances, it is important to monitor whether the mutated virus is extinct via massive testing for the virus sub-type. If successful, the strategy will lead to lower and lower numbers of the sub-type, and it will eventually die out. An important question is, for how long time one should wait to be sure the sub-type is extinct? We use a hidden Markov model for infection spread and an approximation of a two stage sampling scheme to infer the probability of extinction. The potential of the method is illustrated via a simulation study. Finally, the model is used to assess the Danish containment strategy when SARS-CoV-2 spread from mink to man during the summer of 2020, including the Cluster-5 sub-type. In order to avoid further spread and mink being a large animal virus reservoir, this situation led to the isolation of seven municipalities in the Northern part of the country, the culling of the entire Danish 17 million large mink population, and a bill to interim ban Danish mink production until the end of 2021.
One-pot synthesis of high-concentration mixed-shell polymeric micelles as nanochaperones for the renaturation of bulk proteins
Authors: Deng Fei , Yang Menglin , Zhang Yanli , Wu Xiaohui , Ma Rujiang , Ma Feihe , Shi Linqi
Published: December 2021

A one-pot synthesis of high-concentration mixed-shell polymeric micelles and synthetic nanoparticles can be used to assist the refolding of bulk denatured proteins and stabilize native proteins for long-term storage.
Mobile energy‐to‐home integration: An adaption of mobility as a service in urban energy systems
Authors: Luo Fengji , Zhao Zehua , Rashidi Taha Hossein
Published: December 2021

Mobility as a Service (MaaS) represents a paradigm shift from personally owned transportation modes towards mobility provided as a service. Using electric vehicles (EVs) as a mobile energy storage media, this article presents a new application scenario of MaaS in urban energy systems, referring to as the mobile energy to home (ME2H) integration. An architectural design of the ME2H system is proposed in this study, which is cantered by a ridesharing‐like booking system. Through the booking system, a customer can appoint nearby on‐road EVs to come to plug in and temporarily supply energy to their site with an agreed price lower than purchasing energy from the external grid. The ME2H booking system then interfaces with the customer‐side home energy management system and the EV driver‐side trip planner. Based on the ME2H booking schedules, the two decision‐making systems plan the household appliance operations and travel paths for the ME2H service receiver (the customer) and provider (the EV driver), respectively. This study also investigates two representative scenarios to demonstrate the effectiveness of ME2H in urban energy systems.
Numerical computation of the cut locus via a variational approximation of the distance function
Authors: Générau François , Oudet Edouard , Velichkov Bozhidar
Published: December 2021

We propose a new method for the numerical computation of the cut locus of a compact submanifold of ℝ3 without boundary. This method is based on a convex variational problem with conic constraints, with proven convergence. We illustrate the versatility of our approach by the approximation of Voronoi cells on embedded surfaces of ℝ3.
Changes in Plasma Beta-Endorphin Levels in Stage III–IV Nasopharyngeal Carcinoma Patients Post World Health Organization 3-Step Analgesic Ladder Therapy
Authors: Surarso Bakti , Purnami Nyilo , Perdana Rizka Fathoni
Published: December 2021

Introduction Nasopharyngeal carcinoma (NPC) is the most common malignancy in the field of otorhinolaryngology, and chronic pain is identical with this malignancy. Pain therapy according to World Health Organization (WHO) recommendations is WHO 3-step analgesic ladder. Pain is subjective and related to the function of beta-endorphin hormone.

Objective Analyzing the relationship between the degree of pain and plasma endorphin levels in stage III–IV NPC patients before and after the administration of WHO 3-step analgesic ladder.

Materials and Methods The study design used pretest and posttest without control design. Participants were given WHO 3-step analgesic ladder therapy for 3 days. The participants then rated the pain scale using the visual analog scale (VAS) and plasma beta-endorphin levels in venous blood. The statistical test used the dependent t-test, Wilcoxon test, and Spearman test with p < 0.05, confidence interval: 95%.

Results There were 14 stage-III NPC patients with moderate pain (78.57%) and 31 stage-IV NPC participants had moderate pain (83.87%; p = 0.071). The VAS value in the moderate pain group before and after therapy was 82.22% and 66.67%, respectively (p < 0.001). The values of plasma beta-endorphin levels before and after therapy were 74.89 ± 69.12 and 72.49 ± 75.53 pg/mL, respectively (p = 0.647). Plasma beta-endorphin levels were −19.20 ± 37.72 pg/mL (mild pain), −4.76 ± 35.30 pg/mL (moderate pain), and −21.67 ± 6.27 pg/mL (severe pain; p = 0.717).

Conclusion Pain levels in advanced NPC patients have decreased after the therapy, but plasma beta-endorphin levels have no significant difference.
Effectiveness of School-Based Teaching Program on Knowledge Regarding Recognition and Management of Adolescent's Suicidal Behavior Among School Teachers in Selected Schools in Sikkim
Authors: Marbaniang Wanrinylla , Sharma Champa , Shadap Arkierupaia
Published: December 2021

Objective Suicide is a global public health concern. It is the second leading cause of death among 15 to 29 years old. Suicide ideation often emerges in adolescence and is prevalent among this age group. With the help of leaders, teachers as mentors can play an effective role in the prevention of suicide among children and young adults. The present study was performed to assess the effectiveness of school-based teaching programs on knowledge regarding the recognition and management of adolescent's suicidal behavior among school teachers.

Materials and Methods A quantitative research approach with a pre-experimental (one group pre-test and post-test) research design was adopted. The study was conducted at Government schools of East Sikkim among 80 secondary school teachers. The samples were assigned through the purposive sampling technique. A pre-designed knowledge questionnaire was used to assess the knowledge of schoolteachers. A pre-test was conducted during the first week of data collection, which was followed by a school-based teaching program regarding recognition and management of adolescents' suicidal behavior on the second week. A post-test was conducted during the fourth week using the same pre-designed knowledge questionnaire. Data analysis was done using the SPSS version 25 applying descriptive and inferential statistical methods.

Results The study findings revealed that in pre-test knowledge score, 5% had good knowledge, whereas in post-test, score 50% had good knowledge regarding recognition and management of adolescent's suicidal behavior. The mean score during the pre-test was 12.78 ± 2.87 and the mean score during the post-test was 16.44 ± 2.50. The computed paired “t” value (11.9) was higher than the tabled value (t
79 = 1.99; p < 0.05). An association was found between pre-test knowledge score regarding recognition and management of adolescent's suicidal behavior with gender, religion, and years of working experience at p < 0.05 level.

Conclusion The study concluded that school-based teaching programs helped secondary school teachers to improve their knowledge regarding adolescents' suicidal behavior. The gain in knowledge from the school-based teaching program will help them recognize and manage adolescents with suicidal behavior and initiate appropriate referrals in the future.
Financial regulation in the age of the platform economy
Authors: Eichengreen Barry
Published: December 2021

Platform businesses allow for collaboration with nontraditional partners and bring together different categories of customers, in the financial context savers and investors or lenders and borrowers, creating large, scalable networks of users. Their entry into finance promises potential benefits to consumers in the form of new products, lower prices, wider choice, and enhanced consumer experience. At the same time, their new business models and technologies potentially threaten the dominant position of traditional financial services providers and create challenges for regulators. Platform businesses can use their preferential access to customer data to skim off high-quality loans, leaving only low-quality customers for other lenders. Their ability to offer complementary nonfinancial services that cannot be supplied by FinTech start-ups and banks can make it difficult or unattractive for customers to switch to alternative providers. This danger is especially acute when BigTech firms have monopoly power in other markets that complement financial services.
Three extremes in one experiment engender exotic phases
Authors: Patrick Chris
Published: December 2021

Setup combines low temperature, a strong magnetic field, and high pressure to explore systems under extreme conditions with optical spectroscopy.
Visualizing magnetically driven converging radiative shock generated in Z-pinch foil liner implosion
Authors: Meng S. J. , Ye F. , Xu Z. P. , Yan X. S. , Jiang S. Q. , Lu J. , Huang Z. C. , Yi Q. , Chen F. X. , Yang R. H. , Ning J. M. , Xu R. K. , Li Z. H.
Published: December 2021

A study of the evolution and structure of magnetically driven converging radiative shock waves generated in Z-pinch foil liner implosion at an 8-MA pulsed-power facility is presented. End-on extreme ultraviolet images show an inward propagating shock that is circular to <±5% as a function of azimuthal angle, with a standard deviation in the emission intensity of <±30%, implying good cylindrical symmetry. The launch time and shock trajectory are determined by linear fitting of the measured data, giving a shock speed of Mach 6. One-dimensional radiation hydrodynamics MULTI-IFE-Z simulations agree with the experimental observations qualitatively and confirm the existence of a radiative precursor. It is demonstrated with experiment and simulation that the radiative shock wave is generated by magnetic piston compression of dense plasma shell. Analytic estimates of the post-shock plasma conditions suggest that these Z-pinch magnetically-driven high-Mach shocks are strongly radiatively cooled. It is applicable to the optically thick downstream, optically thin upstream radiative shock regime; thus, it can be described by three-layer model, which potentially could be applied to scale studies of astrophysical shocks in the laboratory.
Patterning coexisted micro-/nanostructures for consequential camouflage via mechanical constraint harnessed surface instability
Authors: Li Bo , Wu Yehui , Sun Ya , Ma Wentao , Jiang Lei , Yang Zicheng , Li Fei , Chen Guimin
Published: December 2021

Coexisting micro-/nanostructures on a stretchable substrate offer localized functionality with programmability and dynamic regulation. Yet, the combination of different fabrication techniques is challenging. In this paper, a one-step methodology for such a surface is proposed by harnessing wrinkle instability at the targeted area with selected mechanical constraint during soft lithography. Partly covered by patterned constraints, a surface with nanostructures that replicate a template is obtained while the unconstraint part wrinkles as a result of classical morphology instability. The effect of constraints is investigated experimentally to guide the generation of two optical performances, chemical color and structural color, at the coexisting surface structures. A camouflage demonstration is illustrated, utilizing the strict consequence of wrinkle-flattening and structural color redshift upon stretching.
Tuning mechanical metastability in FeMnCo medium entropy alloys and a peek into deformable hexagonal close-packed martensite
Authors: Wei Shaolou , Xu Michael , LeBeau James M. , Tasan Cemal Cem
Published: December 2021

We report here the compositional dependency of face-centered cubic (FCC) to hexagonal close-packed (HCP) martensitic transformation in FeMnCo medium entropy alloys (MEAs) and insights into the underlying transformation mechanisms. To this end, we designed MEAs with the same Fe-to-Mn ratio and explored the phase stability therein. Higher Co content was found to facilitate the FCC-HCP transformation kinetics. In situ electron backscatter diffraction studies underpinned an FCC-HCP-(new)FCC transformation chain and its underlying atomistic mechanisms were directly explored via aberration-corrected scanning transmission electron microscopy.
Higher-order effects, continuous species interactions, and trait evolution shape microbial spatial dynamics
Authors: Swain Anshuman , Fussell Levi , Fagan William F.
Published: December 2021

Significance

Persistently diverse microbial communities are one of biology’s great puzzles. Using a modeling framework that accommodates high mutation rates and a continuum of species traits, we studied microbial communities in which antagonistic interactions occur via the production of, inhibition of, and vulnerability to toxins (e.g., antibiotics). Mutation size and mobility enhanced microbial diversity and temporal persistence to extraordinarily high levels. These findings—including the discovery that the duration of the transient phase in community assembly provides a guide to equilibrial diversity—highlight the potentially critical role that antagonistic interactions play in promoting the diversity of bacterial systems. Such interactions, together with resource-driven interactions and spatial structure, may drive the enigmatic levels of biodiversity seen in microbial systems.
Mechanistic analysis of carbon–carbon bond formation by deoxypodophyllotoxin synthase
Authors: Tang Haoyu , Wu Min-Hao , Lin Hsiao-Yu , Han Meng-Ru , Tu Yueh-Hua , Yang Zhi-Jie , Chien Tun-Cheng , Chan Nei-Li , Chang Wei-chen
Published: December 2021

Significance

The completion of the tetracyclic core of etoposide, classified by the World Health Organization as an essential medicine, by the Fe/2OG oxygenase deoxypodophyllotoxin synthase follows a hybrid radical-polar pathway not previously seen in other members of this enzyme class. The implication of a substrate-based benzylic carbocation in this mechanism will inform ongoing efforts to create analogs of this important drug with improved or emergent properties and represents a new route for resolution of the initial substrate radical that is common to members of the class. This study adds to our understanding on a growing number of biochemical transformations in which carbocation intermediates are likely to be crucial.
Locust density shapes energy metabolism and oxidative stress resulting in divergence of flight traits
Authors: Du Baozhen , Ding Ding , Ma Chuan , Guo Wei , Kang Le
Published: December 2021

Significance

Migratory locusts display striking phenotypical plasticity. Gregarious locusts at high density can migrate long distances and cause huge economic losses of crops. By contrast, solitary locusts at low density have limited ability in long-distance flight. However, the mechanisms underlying such flight capacity variation are poorly understood. Here, we found that the flight muscle of solitary locusts has a higher catabolic capacity that is associated with greater reactive oxygen species (ROS) generation during high-velocity flights. By contrast, a relatively lower catabolic capacity in gregarious locusts is associated with lower ROS generation during long-distance flights. This finding uncovers the metabolic mechanism of locust flight trait alteration in response to density changes and enhances our understanding of the biological processes enabling locust migration.
Flexibility of telomerase in binding the RNA template and DNA telomeric repeat
Authors: Choi Woo Suk , Weng Peter J. , Yang Wei
Published: December 2021

Significance

Telomerase reverse transcriptase (TERT) has a conserved central cavity near the active site. Using enzymatic and mutagenesis analyses, we provide experimental evidence that an artificially looped-out telomeric repeat in the DNA primer can be transiently accommodated in the cavity of
Tribolium castaneum
(
tc
TERT). Kinetically,
tc
TERT requires a minimum of 4 bp between the RNA template and DNA primer for efficient DNA synthesis. An RNA duplex downstream of the RNA-template region after a flexible linker enhances the efficiency of primer extension by
tc
TERT. In addition to the peripheral cavities that accommodate looped-out RNA during each telomeric repeat synthesis, the central cavity that can accommodate the looped-out DNA may aid RNA-template translocation between cycles of telomeric repeat synthesis.
Robust electrical contacts integrating a liquid metal bridge for mechanical switches
Authors: Zhu Xiaonan , Yang Fei , Wang Haoran , Zhao Siyuan , Wu Yifei , Wu Yi , Rong Mingzhe
Published: December 2021

Intrinsic roughness of solid surfaces causes a series of inevitable shortcomings in the use of mechanical electrical contacts, among which one of the most fatal is the repulsive electrodynamic force arising from high currents. A large contact force coming from a heavy holding mechanism helps to suppress the repulsive effect whereas the mechanism consumes energy and remains to be challenging for a compact switching device. Here, a liquid metal (LM) bridge is introduced to wet solid electrodes to eliminate contact issues. Four instability patterns induced by the electromagnetic pinch effect are identified to characterize LM bridge’s response to high currents. Simulation results reveal that an inner vortex caused by uneven distributions of current density and electrodynamic volume force leads to the rupture of a necked LM bridge. With a uniform structure, a cylindrical LM bridge is proved to be robust with respect to an impulse current higher than 10 kA, exceeding a commercial compact relay by a factor of more than 10 in terms of current withstand performance. Our research facilitates compact and energy-saving switch equipment and has a potential to realize arbitrary desired levels of high current withstand without the use of a holding mechanism. This paper also offers deep insights into the high current applications of LM from the perspective of fluid related physical mechanisms.
Microstructure and phonon behavior in W/Si periodic multilayer structures
Authors: Kumar Niranjan , Nezhdanov Aleksey V , Garakhin Sergey A , Yunin Pavel A , Polkovnikov Vladimir N , Chkhalo Nikolay I , Mashin Aleksandr I
Published: December 2021

The crystallinity of the tungsten (W) phase was improved with an increase in the thickness of this layer in the periodic W/Si multilayer structure. Both the α- and β-W phases were grown simultaneously and the contribution of these phases was modified by a change in the thickness of the W layers. For thinner W layers, the thermodynamically metastable β-W phase dominated, and with an increase in thickness, this phase was suppressed and the stable α-W phase became prominent. The crystallite size of these phases was almost linearly proportional to the thickness of the W layers in the multilayers. With the increase in thickness of Si layers in multilayers, Raman scattering showed a decrease in the bond-angle deviation of Si–Si bonding in the amorphous Si phase. The study revealed ordering of Si–Si bonding in the amorphous phase of Si with an increase in thickness of these layers in periodic W/Si multilayers.
Does a container of ideal gas increase in temperature when accelerated and stopped?
Authors: Goh Ker Liang
Published: December 2021

An insulated container consisting of two ideal gas atoms are used. It is shown using rectilinear motion and elastic collisions with the walls of the container how the root mean square speed of the atoms change during acceleration of the container and after the container comes to a sudden stop.
Long-time memory effects in a localizable central spin problem
Authors: Ng Nathan , Rabani Eran
Published: December 2021

We study the properties of the Nakajima–Zwanzig memory kernel for a qubit immersed in a many-body localized (i.e. disordered and interacting) bath. We argue that the memory kernel decays as a power law in both the localized and ergodic regimes, and show how this can be leveraged to extract t → ∞ populations for the qubit from finite time (Jt ⩽ 102) data in the thermalizing phase. This allows us to quantify how the long-time values of the populations approach the expected thermalized state as the bath approaches the thermodynamic limit. This approach should provide a good complement to state-of-the-art numerical methods, for which the long-time dynamics with large baths are impossible to simulate in this phase. Additionally, our numerics on finite baths reveal the possibility for unbounded exponential growth in the memory kernel, a phenomenon rooted in the appearance of exceptional points in the projected Liouvillian governing the reduced dynamics. In small systems amenable to exact numerics, we find that these pathologies may have some correlation with delocalization.
Implications of gamma-ray photon measurements at the LHAASO on Lorentz symmetry *
Authors: Ling Yi , Liu Yuxuan , Wang Sai , Wu Meng-He
Published: December 2021

The Large High Altitude Air Shower Observatory (LHAASO) has reported the measurement of photons with high energies of up to 1.42 PeV from twelve gamma-ray sources. We are concerned with the implications of the LHAASO data on the fate of Lorenz symmetry at such high energy levels; thus, we consider the interaction between gamma rays and photons in the cosmic microwave background (CMB) and compute the optical depth, mean free path, and survival probability of photons from these gamma-ray sources. Employing the threshold value predicted by standard special relativity, the lowest survival probability for observed gamma ray photons is found to be approximately 0.60, which is fairly high and implies that abundant photons with energies above the threshold may reach the Earth without Lorentz symmetry violation. We conclude that it is unreasonable to argue that Lorentz symmetry would be violated using current observations at the LHAASO.
Evaluation the Safety and Security Procedures used In X-ray Clinics in Al-Harthiya-Baghdad
Authors: Abdul Hussian Thuraya A. , Farman Anwar kh.
Published: December 2021

Radiation is a form of energy, its emitted either in the form of particles such as α-particles and β-particles (beta particles including the electron and the positron) or waves such as sunlight, X-rays and γ-rays. Radiation found everywhere around us and it comes from many different sources naturally or man-made sources. In this study a questionnaire was distributed to people working in the field of X-rays that used for a medical imaging (X-ray and CT-scan) to evaluate the extent of awareness and knowledge in estimate the damage of ionizing radiation as a result of wrong use. The questionnaire was distributed to medical clinics in Al-Harithiya in Baghdad, which it’s considered as one of the important areas in Iraq to attract and treat patients. It’s found that most of the commitment of radiography clinics by safety and security procedures. Most of the radiology clinics abide by most of the Iraqi Ministry of Health laws. However, some clinics did not implement some of the security and safety conditions
The use of aluminum oxide as a sensor
Authors: Jary Aqeel Maryoosh , Atiyah Sadeq Naeem , Abbood Ali Nazar , Alhamd M. W.
Published: December 2021

The comes about of optical and photoluminescence properties of anodic alumina shaped within the acidic electrolyte and subjected to high-temperature warm treatment are depicted in article. It was found that the photoluminescence properties of anodic alumina decided by the oxygen opportunities with diverse values of the charge states and pollutions within the frame of corrosive buildups. As a premise of limit finders in terms of the mechanical quality the substrates shaped within the oxalic electrolyte and altered by warm treatment at 800 °C are preferred. Variations of plans dilatometric microrelays sensors of temperature based on anodic alumina are advertised. For different ranges of temperatures and working conditions ideal plans are chosen.
Silicon dioxide dispersed effects on some physical and mechanical properties of Al2Si2O5(OH)4
Authors: Issa Tarik T. , Abid Noor Kadhum , Abid Mustafa Kadhum
Published: December 2021

Kaolin and silica of 50 μm grain size were used in different weight percentage. Four combinations have been selected as green compacted bodies. Different sintering temperatures ranging from (1000 – 1400) °C were used to sintered all the combinations under static air. The sintered density, thermal conductivity compression strength and linear shrinkage were tested after sintering. The common behavior indicated that the improvement with its optimum results was found at the combination (Kaolin 20-SiO2 80) Wt. %, sintered at 1400 °C, for 3 hours under static air.
Mechanical Properties of Heat Cured Acrylic Resin Reinforced with Natural Sisal Fibers Powder
Authors: Hameed Teba M. , Al-Dabbagh Balqees M. , Jasim Ragdaa K.
Published: December 2021

Materials and Methods: In total, 90 specimens were prepared to be used in the study. The specimens were divided into (3) main groups depended on the presence of sisal fibers powder, first group (30) specimens of heat cure PMMA without additives (control), second and third experimental groups of 60 specimens of heat cure PMMA with salinized sisal fibers powder with two different weight percentages (1 and 3%) wt. Three point bending test was used to measure the flexural strength of the specimens, while the impact strength was done by impact testing Charpy’s machine and tensile test was performed according to ASTM (D-638). Data analysis was performed using (ANOVA) test. The results of this study refer to a highly significant in the flexural strength and tensile strength of specimens reinforced with sisal fibers powder compared with control specimens. Non-significant difference was detected in impact strength among the reinforced groups and control gro. Reinforcement of acrylic resin with natural sisal fibers powder affects its flexural strength and tensile strength with non-significant in impact strength.
Detect Environment Pollution by GIS for Some Regions in Baghdad City
Authors: Abdullah Sundus A. , Aziz Tabbark R.
Published: December 2021

The present study aims at assessing the status of heavy metals such as nickel, cadmium and lead to pollute some areas of Baghdad city. In this study the spectral absorption device and the program ArcGIS 10.2 will using. The soil samples were taken from five different locations in Baghdad, including Ameriya, Kadhimiya, Palestine Street, Jadiriyah and Taji for the 5cm depth layer on both sides of the road. This work on soil samples has been completed in two :phases 1 - Preparation of samples: For the purpose of converting solid material into a extract containing elements in the form of single ions can be estimated by the device 2-Determination of elements: Samples prepared to the device for the purpose of estimating their concentration in PPM units using the Atomic Absorption Spectrometer. The findings of this study can be summarized as follows: 1-The results showed that nickel concentrations ranged from 0.0336-0.1512 ppm where the lowest value of nickel was found in Kadhimiya by 0.0336 and the highest value was found in Ameriya with a value of 0.1512 and it is considered to be a non-polluting nickel in these areas because it did not exceed the critical limit 1.3 ppm. Which was explained by GIS using the map of Baghdad and determine the area studied. The results were distributed by the interpolation method using ArcGIS 10.2 program, it was noticed that there are high pollutant values in an area considered agricultural according to the classification of human settlements, which is the Jadiriyah area, where Lead (Pb) element showed a strange behaviour by its presence in high values in Jadiriyah, where its source is unknown. A future research will be prepared to study the sources of these pollutants for treatment.
The effect of replacing iron atoms instead of zinc of the quaternary compound CZTS
Authors: Mohammed Abubaker.S.
Published: December 2021

In this article, the quaternary compound Cu2MSnS4 was prepared in a simple and inexpensive approach, where M is the iron (Fe) and zinc (Zn) atoms by the spin coating method on a glass substrate at room temperature (RT), as a result of replacing Zn atoms by Fe. Quaternary Cu2ZnSnS4 (CZTS) and Cu2FeSrS4 (CFTS) structural and optical properties have been studied successfully. The material has been identified by X-ray diffraction, and it was discovered that CZTS has a polycrystalline Tetragonal (kesterite) structure, whereas CFTS has a Tetragonal (stannite) structure. A reduction in the full width half maximum (FWHM) of the preferred plane implies a high degree of crystallization. The structural properties of the film surface, such as grain size and roughness, were studied by Atomic force microscopy (AFM). The results explain an increase in nanoparticle size and surface roughness when Fe is substituted by Zn in the CZTS structure. The absorption coefficient values of all designed compounds in visible regions are greater than 104/cm, and the results show that the absorbance coefficient increases with Fe add. The CZTS films showed an energy gap of 1.88 eV, and this value became 1.69 eV with substituted Fe instead of Zn.
Study of the matter density distributions of halo nuclei 6He and 16C using the binary cluster model
Authors: Abdullah S Q , Abdullah A N
Published: December 2021

The harmonic oscillator (HO) and Gaussian (GS) wave functions within the binary cluster model (BCM) have been employ to investigate the ground state neutron, proton and matter densities as well as the elastic form factors of two-neutron 6He and 16C halo nuclei. The long tail is a property that is clearly revealed in the density of the neutrons since it is found in halo orbits. The existence of a long tail in the neutron density distributions of 6He and 16C indicating that these nuclei have a neutron halo structure. Moreover, the matter rms radii and the reaction cross section (σr) of these nuclei have been calculated using the Glauber model.
The importance of doping TiO2into polypyrrol nanofibers to improve their optical sensitivity
Authors: Kareem Omar A. , Mohameed Sabri J. , Ibrahim Isam M.
Published: December 2021

In this study Electrochemical polymerization was used to make polypyrrol nanofiber. The in situ chemical oxidative polymerization approach was used to create a nanocomposite of polypyrrole PPy-TiO2. To achieve homogeneous dispersion inside the PPy matrix, the TiO2was dissolved and ultrasonically dispersed. The surface morphology of polypyrrol and PPy/TiO2nanocomposites was studied using field emission scanning electron microscopy (FE-SEM), which revealed of a polypyrrol nanofibre network and showed that the TiO2nanoparticles was well incorporated. The produced PPy/TiO2nanocomposite was characterized using XRD (X-Ray diffraction) and FT-IR (Fourier Transform Infrared). The formation of TiO2nanoparticales on a PPy layer matrix was discovered, as well as homogeneous dispersion of TiO2inside the PPy matrix and considerable interaction between PPy and TiO2. The produced PPy/TiO2nanocomposite sensors’ response was investigated towards of light-power sensitivity. The PPy/TiO2synergistic effects improve the light sensitivity qualities of the photodetector. The maximium sensitivity of PPy/TiO2was around (188 %) at 20% TiO2concentration at a light power of 30 mW for a laser diode 720 nm, while the rise time and fall time was ≈ 2.5sec.
Effect of Variation MWCNTs in Synthesis Zirconia Prepared by Uniaxial Pressed Technique
Authors: Ahmed Hadeer Sh , Majeed Sadeer M. , Ahmed Duha S
Published: December 2021

The effect of addition different weight percentage (wt. %) of treated MWCNTs on zirconia matrix as a composite structure using method uniaxial pressed for fabrication and enhancement mechanical, microstructural properties of zirconia have been investigated in the present study. The composite material have prepared by adding yttrium oxide (3% mol. Y2O3) to zirconia for stabilized in the tetragonal phase with homogeneous distribute and reinforcement changed weight percentage of (2%, 5%, 7%, and 10%) wt. of F-MWCNTs to result (3% mol.Y2O3-ZrO2/F-MWCNTs) nanocomposite samples by pressing uniaxiall at pressure of (624) MPs in the metal-die cylinder to results pellets of (10 mm diameter). The resulting pellets were sintered in air at (1550 °C) temperatures for two hours. The samples were characterized by XRD analysis to demonstrate the phase composition of samples, where The retention was observed on the tetragonal phase in zirconia and the microstructure of the materials have been studied using SEM it is observed that F-MWCNTs were homogeneously distributed in the composite powders without the formation of ropes and bundles up to the highest contents of F-MWCNTs, and EDS showed the percentages for presence of carbon in samples, The micro hardness was studied by Vickers indentation method and Brazilian test that shows improved due to a homogeneous distribution of MWCNT in ZrO2and the densities (Green, Bulk, and theoretical), porosity and liner shrinkage to demonstrate the toughness that reveal many pores and low densification with increasing F-MWCNTs contents, physical and mechanical properties of samples depend on distribution of F-MWCNTs in the matrix.
Interference between Total Solar Radiation and Cloud Cover over Baghdad City
Authors: Al-Taai OsamaT. , Hashim Shiemaa A. , Nassif Wedyan G. , Abbood Zainab M.
Published: December 2021

Clouds greatly affect the elements of climate, energy balance, and solar radiation, which has increased the interest of many researchers in trying to find the best relationships and formulas that link these variables. In this work, the data of the European Center for Medium-Range Weather Forecasts (ECMWF) was relied on. The research aims to find the overlap between Cloud Cover (Low, Middle, High, and Total), (LCC, MCC, HCC, and TCC) respectively, with Total Solar Radiation (TSR) of Baghdad city, for the period (1981-2013), the work was carried out with the monthly and annual data of the (Low, Middle, High, and Total) cloud cover and the total solar radiation falling on a horizontal surface. And by using the correlation coefficient Spearman rho test (rs) to find the strength of the relationship between total solar radiation and cloud cover, it was found that there is an inverse relationship between the total solar radiation falling on a horizontal surface and the (Low, Middle, High, and Total) cloud cover.
Wide Range Responsivity Photodetector of Zr-Au-Ag Oxide NPs Prepared By Pulsed Laser Ablation
Authors: Hassan Haider J. , Abbas Ahmed k. , Ibrahim Isam M.
Published: December 2021

Metal-ceramic composite particles are of increasing interest due to their potential applications in photodetectors as well as next-generation catalysts. The zirconium-gold system has received little attention due to the lack of controllable preparation methods. Well-known methods for the deposition of gold Nano shells on zirconium spheres, however, should be adaptable for similar zirconium-based materials. Here, we present a method to synthetic approach to the well-controlled deposition of gold on the surface by laser ablation. The results shed light on the parameters governing the preparation of zirconium _ gold composite particles and our synthetic approach provides a promising tool for future developments in complex nanomaterials design. As well as studying the structural and optical properties of gold, silver and zirconium nanoparticles by preparing those particles in the above method and studying the properties of the resulting materials as a photodetector. The surface morphology, structure, and composition of the layer were studied using a variety of spectroscopic diffraction and real-space imaging techniques, including SEM, EDX and AFM.
Art Image Compression Based on Lossless LZW Hashing Ciphering Algorithm
Authors: Mohammed Sajaa G. , Abdul-Jabbar Safa S. , Mohammed Faisel G.
Published: December 2021

Color image compression is a good way to encode digital images by decreasing the number of bits wanted to supply the image. The main objective is to reduce storage space, reduce transportation costs and maintain good quality. In current research work, a simple effective methodology is proposed for the purpose of compressing color art digital images and obtaining a low bit rate by compressing the matrix resulting from the scalar quantization process (reducing the number of bits from 24 to 8 bits) using displacement coding and then compressing the remainder using the Mabel ZF algorithm Welch LZW. The proposed methodology maintains the quality of the reconstructed image. Macroscopic and quantitative experimental results on technical color images show that the proposed methodology gives reconstructed images with a high PSNR value compared to standard image compression techniques.
Development of Effectual Substrates for SERS by Nanostructures-on flexible surfaces
Authors: Humud Hammad R. , Moaen Fatimah Jumaah
Published: December 2021

The current study examines recent advancements in surface-enhanced Raman scattering (SERS), a technique that employs flexible surfaces as an active substrate, this surfaces consist from two-dimensional thermo-plasmonic grating. With 53 nm Au layer (was deposited on the 2D grating structure of the PDMS by the PVD method). The explosive wire technique was used to preparing Ag nanoparticles that were used for the purpose of SERS. The effect of the plasmonic nanostructures on the absorption spectra and Surface - Enhanced Raman Scattering (SERS) activities was examined. Rhodamine 6G dye was used as a probe molecule. X-Ray diffraction (XRD) was used to examine the structural characteristics of the nanoparticles. The morphology was assessed using Field Emission Scanning Electron Microscopy(FESEM). A twin beam UV-Vis Spectrophotometer was used to measure the absorption of the combined Rh6G dye (concentration 1×10“–6M) with the nanostructures. a Sunshine Raman microscope system and a 50mm objective lens, used for investigating the Raman spectra of the Rh6G combined with nanostructures. The results showed that the enhancement factor (EF) for SERS of R6G (1×M) reached to (2.2×10 3) When using Ag nanoparticles and (0.08 × 103) when R6G deposited directly on the flexible substrates without nanostructures at the wave number (1650 cm−1), we produced a recyclable, homogeneous, and highly sensitive SERS substrate with dependable reproducibility. For the SERS substrate, a surface made up of two-dimensional (2D) flexible grating substrates was chosen to provide multiple modalities in electrical and medicinal applications.
New Comparative Study of High-Sensitivity H2Gas Sensors at Room Temperature Based on ZnO NWs Grown on Si and PS/Si Substrates without Catalyst by Wet Thermal Evaporation Method
Authors: Abdulgafour H. I. , Hassan Thamer A.A. , Yam F.K.
Published: December 2021

A novel approach for growing high-quality ZnOnano-structures with no catalyst using an inexpensive technique that is called wet thermal evaporation has been investigated for gas sensor applications. For a novel comparative investigation of H2gas sensors, large regions regarding the well-aligned coral reef-like ZnOnano-structures on the porous Si (PS) and flower-like nano-rods on Silicon were successfully utilized. In the presented study, a Pd/ZnO/Pd metal-semiconductor-metal was efficiently created for H2gas sensor device employing high-quality ZnOnano-structures that are grown on a variety of the substrates. At room temperature, the sensitivity related to ZnO/PS and ZnO/Si is evaluated at various flow rate values (25sccm, 50sccm, 100sccm, and 150sccm) of 2% H2gas. The I-V characteristics revealed that ZnO/Si has a larger hydrogen gas barrier height than ZnO/PS. At room temperature, the ZnO/Si sensitivity was about 105% and 190% for ZnO/PS at 150sccm flow rate. The sensors’ sensitivity and optimum operating temperature for ZnO/PS at 150sccm of H2gas are 350% (at 100 Celsius), which is higher compared to double the maximal sensitivity with regard to ZnO/Si device at a temperature of 150 Celsius. This research concluded that because ZnO/PS has a large specific area, it has a greater possibility of reacting with gases and increasing sensitivity at the temperature of theroom.
Gold nanoparticles fabricated by the electrical wire explosion technique, deposited on a porous silicon as an active substrate for surface-enhanced Raman scattering (SERS)
Authors: Jaleel Ansam F , Wasfi Ahmed S
Published: December 2021

This study aims to improve the surface-enhanced Raman scattering (SERS) using gold nanoparticles prepared by the wire explosion technique and deposited on an etched silicon substrate. This spectral technique is highly dependent upon physicochemical properties of the substrate material, to detect very low concentrations of the toxic materials.

The morphological and structural features of the prepared gold nanoparticles (AuNPs) have been investigated by the field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The FE-SEM images illustrated that the deposited AuNPs have a non-uniform spherical shape with a rough surface and there were nanogaps between them acting as hotspots at the surface. While the X-ray diffraction pattern indicated the existence of the (111) plane which confirmed the crystalline nature of the AuNPs. Rh6G dye was used as a probe material to examine the performance of these nanoparticles as a SERS substrate. The Raman scattering spectrum of the rhodamine RH6G dye enhanced greatly due to the existence of these nanoparticles, where the enhancement factor (EF) was 2.23×106 when using a deposited AuNPs of concentration 13.46 ppm which is equal to 3×10-5 M, and a reasonable detection limit for a low dye concentration of 10-14M.