bluuebunny/crossref_metadata_2025 huggingface dataset:
Significant contribution of organics to aerosol liquid water content in winter in Beijing, China
Authors: Jin Xiaoai , Wang Yuying , Li Zhanqing , Zhang Fang , Xu Weiqi , Sun Yele , Fan Xinxin , Chen Guangyu , Wu Hao , Ren Jingye , Wang Qiuyan , Cribb Maureen
Published: July 2019

Abstract. The aerosol liquid water content (ALWC), an important component of atmospheric particles, has a significant effect on atmospheric optical properties, visibility and multiphase chemical reactions. In this study, ALWC is determined from aerosol hygroscopic growth factor and particle number size distribution (PNSD) measurements and also simulated by the ISORROPIA II thermodynamic model with measured aerosol chemical composition data at an urban site in Beijing from 8 November to 15 December 2017. Rich measurements made during the experiment concerning virtually all aerosol properties allow us not only to derive the ALWC but also to study the contributions by various species for which little has been done in this region. The simulated ALWC including the contribution of organics and the calculated ALWC are highly correlated (coefficient of determination R2 = 0.92). The ALWC contributed by organics (ALWCOrg) accounts for 30 % ± 22 % of the total ALWC during the sampling period. These results suggest a significant contribution of organics to ALWC, which is rather different from previous studies that showed negligible contributions by organics. Our results also show that ALWC correlates well with the mass concentrations of sulfate, nitrate, and secondary organic aerosols (SOA) (R2 = 0.66, 0.56, and 0.60, respectively). We further noted that accumulation mode particles play a key role in determining ALWC, dominating among all the aerosol modes. ALWC is an exponential function of ambient relative humidity (RH) whose strong diurnal variation influence the diurnal variation of ALWC. However, there is a three-hour lag between the extremes of ALWC and RH values, due to the diurnal variations in PNSD and aerosol chemical composition. Finally, a case study reveals that ALWCOrg plays an important role in the formation of secondary aerosols through multiphase reactions at the initial stage of a heavy haze episode.
Partitioning of canopy and soil CO2 fluxes in a pine forests at the dry timberline
Authors: Qubaja Rafat , Tatarinov Feyodor , Rotenberg Eyal , Yakir Dan
Published: July 2019

Abstract. Partitioning carbon fluxes is key to understanding the process underlying ecosystem response to change. This study used soil and canopy fluxes with stable isotopes (13C) and radiocarbon (14C) measurements of a 50-year-old dry (i.e., 287 mm of annual precipitation) pine forest to partition the ecosystem’s CO2 flux into gross primary productivity (GPP) and ecosystem respiration (Re) and soil respiration flux into autotrophic (Rsa), heterotrophic (Rh), and inorganic (Ri) components. On an annual scale, GPP and Re were 655 and 488 g C m−2, respectively, with a net primary productivity (NPP) of 276 g C m−2 and carbon-use efficiency (CUE = NPP / GPP) of 0.42. Soil respiration (Rs) made up 60 % of the total ecosystem respiration and was comprised of 24 ± 4 %, 23 ± 4 %, and 13 ± 1 % Rsa, Rh, and Ri, respectively. The contribution of root and microbial respiration to Re increased during high productivity periods, and inorganic sources were more significant components when soil water content was low. Compared to the mean values for 2001–2006 at the same site; (Grünzweig et al., 2009), annual Rs decreased by 27 % to the mean 2016 rates of 0.8 ± 0.1 µmol m−2 s−1). This was associated with decrease in the respiration Q10 values across the same observation by 36 % and 9 % in the wet and dry periods, respectively. Low rates of soil carbon loss combined with relatively high below ground carbon allocation (i.e., 40 % of canopy CO2 uptake) help explain the high soil organic carbon accumulation and the relatively high ecosystem CUE of the dry forest. This was indicative of the higher resilience of the pine forest to climate change and the significant potential for carbon sequestration in these regions.
Present and future changes in winter climate indices relevant for access disruptions in Troms, northern Norway
Authors: Dyrrdal Anita Verpe , Isaksen Ketil , Jacobsen Jens Kristian Steen , Nilsen Irene Brox
Published: July 2019

Abstract. In some seaside communities in northern Norway the vulnerability to weather induced access disruptions is high, due to frequent high impact weather in the region and the dependency on one or few roads particularly exposed to avalanches, wind and rockfall. In this paper we study changes in typical winter weather indices known to potentially cause such access disruptions in the region. A gridded observation-based dataset is used to analyse changes in present climate (1958–2017), while an ensemble of 10 EURO-CORDEX climate model simulations are used to assess expected future changes in the same indices, towards the end of this century. We focus on weather indices associated with snow avalanches, such as maximum snow amount and snowfall intensity and frequency, but also freeze-thaw cycles in terms of temperatures crossing zero degrees Celsius (zero-crossings), total water supply and the frequency of high wind speed are studied. Our results show that there are large climate gradients in Troms county and also in detected changes. In both focus areas, however, we find an increase in studied snow indices in present climate, while a strong decrease is expected in near and far future, particularly in low elevations where snow during winter might become a rarity by 2100. Heavy water supply is rather infrequent in the present climate of Troms, but we show that these events are likely to occur more often in all inland areas in the future. Although the risk of dry snow-related access disruptions might decrease, a warmer and wetter winter climate may increase the risk of wet-snow avalaches and slushflows. We find that zero-crossings, known to destabilize the snow pack and cause rockfall, have increased in most parts of Troms during the last decades, and a further increase is expected for inland regions in the future, while coastal regions can expect less zero-crossings. The higher risk of water and rainfall-induced hazards and more frequent freeze-thaw conditions calls for careful coordination of climate adaptation, cooperation between different sectors, as well as guidance and training of local authorities, especially in exposed and remote regions.
Fluctuations of finite-time Lyapunov exponents in an intermediate-complexity atmospheric model: a multivariate and large-deviation perspective
Authors: Kwasniok Frank
Published: July 2019

Abstract. The stability properties as characterized by the fluctuations of finite-time Lyapunov exponents around their mean values are investigated in a three-level quasi-geostrophic atmospheric model with realistic mean state and variability. Firstly, the covariance structure of the fluctuation field is examined. In order to identify dominant patterns of collective excitation, an empirical orthogonal function (EOF) analysis of the fluctuation field of all of the finite-time Lyapunov exponents is performed. The three leading modes are patterns where the most unstable Lyapunov exponents fluctuate in phase. These modes are virtually independent of the integration time of the finite-time Lyapunov exponents. Secondly, large-deviation rate functions are estimated from time series of finite-time Lyapunov exponents based on the probability density functions and using the Legendre transform method. Serial correlation in the time series is properly accounted for. A large-deviation principle can be established for all of the Lyapunov exponents. Convergence is rather slow for the most unstable exponent, becomes faster when going further down in the Lyapunov spectrum, is very fast for the near-neutral and weakly dissipative modes, and becomes slow again for the strongly dissipative modes at the end of the Lyapunov spectrum. The curvature of the rate functions at the minimum is linked to the corresponding elements of the diffusion matrix. Also, the joint large-deviation rate function for the first and the second Lyapunov exponent is estimated.
Numerical modelling of the tides in the Caspian Sea
Authors: Medvedev Igor , Kulikov Evgueni , Fine Isaac
Published: July 2019

Abstract. The Caspian Sea is the largest enclosed basin on the Earth and a unique object for analysis of tidal dynamics. The Caspian Sea has independent tides only, which are generated directly by tide-forming forces. Based on the Princeton Ocean Model (POM) the spatial and temporal features of tidal dynamics in the Caspian Sea were described in detail. Detailed tidal charts for amplitudes and phase lags of the major tidal harmonics, form factor, tidal range and velocity of tidal currents were plotted. Semidiurnal tides in the Caspian Sea are determined by a Taylor amphidromic system with counterclockwise rotation. The largest M2 amplitude is 6 cm and is located in the Turkmen Bay. The Absheron Peninsula splits this system into two separate amphidromies with counterclockwise rotation to the north and to the south of it. The maximum K1 amplitudes (up to 0.7–0.8 cm) are located in: (1) the southeastern part of the Caspian Sea, (2) the Türkmenbaşy Gulf, (3) the Mangyshlak Bay, and (4) the Kizlyar Bay. The semidiurnal tides prevail over diurnal tides in the Caspian Sea. The maximum tidal range has been observed in the Turkmen Bay, up to 21 cm. The highest velocity of the total tidal currents is observed in the straits to the north and south of Ogurja Ada, up to 22 cm/s and 19 cm/s, respectively. Were made numerical experiments with tidal simulation using different mean sea level MSL of the Caspian Sea (from −25 m to −30 m). Numerical experiments indicate that the spatial features of tides are strongly sensitive to the MSL changes.
The Rupture of Identity and Identification in James Cone's Africana Theology of Existence
Authors: Ringer Christophe
Published: July 2019

In this article, I argue that James Cone's Black Theology and Black Power inaugurates a theological project that contributes to the field of Africana philosophies of existence as conceptualized by Lewis Gordon. The article examines the importance of historical concrete situations, provides a phenomenological analysis of anti-Blackness as bad faith, and explores identity and identification in Cone's theological method. Finally, I argue that these themes contribute to the global relevance of Cone's theology of existence by analyzing the work of South African anti-apartheid activist Steve Biko.
I Know It Was the Blood: Prophetic Initiation and Retributive Justice in the Narratives of John Marrant, Nat Turner, and Frederick Douglass
Authors: Saville Alphonso F.
Published: July 2019

This article emphasizes the generative impact of West African religious culture on early African American Christians by analyzing the use of two symbols, wilderness and blood, in the autobiographical accounts of John Marrant, Nat Turner, and Frederick Douglass. I use Theophus Smith's notion of conjure to reconstruct the hermeneutical lens through which early African Americans read and understood the Bible and to explain how the repetition of symbols evinces Africana religious consciousness. While the Bible provided these authors and narrators with a narrative model for storytelling, the structural patterns and thematic emphases repeated in their texts suggest that Africana spirituality, rather than the doctrines of Euro-American Protestantism, primarily informs the processes by which these narrators construct religious meaning. The repetition of the Bible's symbols, tropes, and themes establishes a written tradition of biblical interpretation—a midrash of the Black Church—a hitherto-unacknowledged phenomenon in African diaspora religious history.
Feminine Ritual Power and African Politics
Authors: Olupona Jacob
Published: July 2019

This response to Laura Grillo's An Intimate Rebuke concentrates on how feminine ritual power, sometime hidden and underplayed in male-dominated politics and public life more generally, has had revolutionary implications in modern African political history and has the potential to affect change in contemporary African states.
Detection and Location of Subsurface Voids Using Seismic Transmission Data
Authors: Gritto Roland
Published: July 2019

Karst is ubiquitous on the peninsula of Qatar, including depressions, sinkholes, and caves. Faulting and fractures play a major role in the development of karst, where fluids find pathways through limestone and dissolve the host rock. The resulting fissures may grow larger as more surface water is funneled through to form cavities or karst. Sinkholes may also form, when cavern roofs collapse, and it is this last characteristic that is of concern to rapidly growing metropolitan areas, that expand in heretofore unexplored regions. Qatar has seen a recent boom in construction, including the planning and development of complete new sub-sections of metropolitan areas. Before planning and construction can commence, the development areas need to be investigated to determine their suitability for the planned project. Of particular concern are ubiquitous karst features that are prone to collapse, particularly when surface loading is increased due to the construction of new buildings. In this paper, we present the results of a study to demonstrate a variety of seismic techniques to detect the presence of a karst analog in form of a vertical water-collection shaft located on the campus of Qatar University, Doha, Qatar. Seismic waves are well suited for karst detection and characterization. Voids represent high-contrast seismic objects that exhibit strong responses due to incident seismic waves. However, the complex geometry of karst, including shape and size, makes their imaging nontrivial. While karst detection can be reduced to the simple problem of detecting an anomaly, karst characterization can be complicated by the 3D nature of the problem of unknown scale, where irregular surfaces can generate diffracted waves of different kind. In our current paper we build upon previous results (Gritto et al, 2015) and employ a variety of seismic techniques to demonstrate the detection and characterization of a vertical water collection shaft analyzing the phase, amplitude and spectral information of seismic waves that have been scattered by the object. The experiment consisted of seismic transmission and reflection surveys, using a 10 kg sledge hammer as a source and three-component 10 Hz geophones to record the data. We used the reduction in seismic wave amplitudes and the delay in phase arrival times in the geometrical shadow of the vertical shaft to independently detect and locate the object in space. Additionally, we use narrow band-pass filtered data combining two orthogonal transmission surveys to detect and locate the object. Our analysis showed that ambient noise recordings may generate data with sufficient signal-to-noise ratio to successfully detect and locate subsurface voids. This is a result of the low intrinsic attenuation of seismic waves by the limestone and dolomite rocks that are ubiquitous throughout Qatar. Being able to use ambient noise recordings would eliminate the need to employ active seismic sources that are time consuming and more expensive to operate.
A New Class of Electrocatalyst Materials for Direct Methanol Fuel Cell Applications
Authors: Zaidi Syed M. Javaid , Al-Ahmed Amir , Bello Mukhtar
Published: July 2019

Direct methanol fuel cell (DMFC) has been attracting lots of attention as a power source for transportation, stationary and portable electronic devices due to the high energy density of methanol and ease of handling compared to gaseous fuels such as hydrogen and natural gas. However, the commercialization of DMFC is still limited due to some technical challenges such as methanol crossover and low methanol electro-oxidation kinetics. In order for fuel cells to be a feasible and viable option amongst clean energy technologies, innovations in the materials developments are required for efficient operation of fuel cells. Many efforts have been made in various research laboratories to develop high-performance catalysts that will enhance the methanol electro-oxidation. Compared to any single-metal catalyst, Pt has shown the highest activity for the electro-oxidation of methanol in an acid environment. However, Pt is expensive and during the methanol electro-oxidation reaction, COads and other organic intermediates such as formaldehyde, formic acid and methyl formate are formed on the Pt surface, which results in poisoning of the Pt catalyst.

Many binary and ternary catalysts for methanol electro-oxidation have been investigated and reported in the literature, most of them based on modification of Pt with some other metal(s). The aim is to accelerate the oxidation of the intermediates and decrease their accumulation so as to improve the catalyst performance. Among the various catalyst formulations, PtRu alloy has shown the best results for the methanol electro-oxidation. Diverse methods have been used to prepare the PtRu-based catalysts for methanol electro-oxidation. Catalyst composition and method of preparation are known to immensely affect the physical property es and electrochemical performance of a catalyst. Thus, there is the need to use a carefully selected approach in order to prepare a catalyst with the highest attainable performance. Incorporation of transition metals into the PtRu catalysts to form ternary catalysts in order to improve the performance of the PtRu catalysts is one of the techniques attracting a lot of interest. In this work, a novel approach have been used for synthesizing a new class of electrocatalyst nanomaterials for electro-oxidation of methanol by incorporation nano-oxides of transition metals. The prepared nanomaterial catalysts were characterized using FESEM, BET surface area, EDX, FT-IR and XRD. The catalysts performance was studied using cyclic voltammetry and compared with the commercial Pt-Ru/C.
Improving Documentation of Cardio-Vascular Disease Risk in Medical Records of Diabetic Patients attending Non Communicable Disease Clinics at West Bay Health Center in Qatar
Authors: Salem Mohamed , Alali Amal , Bashwar Zelikha
Published: July 2019

Background

Patients with type 2 diabetes have an increased prevalence of lipid abnormalities, contributing to their high risk of CVD. Multiple clinical trials have demonstrated signiﬁcant effects of pharmacological (primarily statin) therapy on CVD outcomes in individual subjects with CHD and for primary CVD prevention. Our aim is to improve documentation of cardiovascular disease risk in medical records of diabetic patients attending non communicable disease clinics at west bay health center from 13% to 70% using world health organization cardiovascular disease risk Prediction Charts from September 2014 to January 2015.

Methods

Baseline audit to determine the percentage of cardiovascular disease risk documentation, Brain storming session was done to identify the causes of such problem including fish bone analysis, Survey questionnaire was designated to assess the main causes of the problem and distributed to all nurses working in non communicable disease clinics, The results demonstrated in paretto chart, We discover the main causes of the problem lies on two main causes (nurses were not oriented to new non communicable disease format and some of them were not trained to calculate risk).Intervention in form of: Education session for nurses working in these clinics were done particularly on: Orientation about new format and cardiovascular disease riskdocumentation, Orientation sessions for clinic running physicians, Putting reminder posters in clinics and staff nurse stations. Several audits done retrospectively for two weeks (3 days each week) to show average percentage of documentation in pre-intervention stage from 15th September to 13th November 2014, Several audits done for three weeks (3 days each week) and then weekly for 5 weeks to show average percentage in post-intervention stage ending at 15th January 2015, All data was demonstrated using run chart.

Results

The intervention began in November 2014 to January 2015 reveals that: Percentage of complete cardiovascular risk documentation for diabetic patients average was 7% in pre-intervention stage and increased to average of 59% after the intervention

Conclusions

Intervention in the form of nurse education and physician orientation improved Documentation of cardiovascular disease risk by 52%. Raising the average of documentation from 7% to 59%. Sustainability is very important for success in such improvement processes.
Hypoglycemic and Hypolipidemic Effect of Active Compounds (Glucokinin or Plant Insulin) from Bauhina Variegate L. in Alloxan Induced Diabetic Mice
Authors: Al-Jumaily Essam Fadel
Published: July 2019

The study includes the isolation and extraction of some active molecules like (flavonoid and total poly phenolic) and plant insulin (Glucokinin) from leaves and flowers of B. variegate L. belonging to the family Leguminosae which cultivated in Iraq. Also the study employed an in vivo evaluation of Bauhinia leaves (petroleum ether and methanol extract) and methanol extract and flowers extraction in mice at concentrations (200 and 400 mg/kg) for (LM1 and LM2) and (200 mg/kg) for F given intra peritoneal for 10 days after inducing diabetes mellitus type 2 by alloxan (200 mg/1 kg body weight). The serum was isolated from blood by cardiac puncture for the biochemical tests, including glucose, cholesterol (ch), Triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL) and very low density lipoprotein (VLDL). At day 10 the animal was killed and the liver and pancreas were kept in 10% formalin for preparation of histopathological sections. We concluded that the Plant insulin (Glucokinin) may be responsible for some of the actions at plant extracts for their antidiabetic properties. From the observations, it was concluded that the reduction of blood glucose levels in diabetic rats were found to be dose dependent and also dependent on duration of action. So it might be useful in the treatment of diabetes without toxicity.

Keywords

Bauhinia variegata, Antidiabetic activity, Hyperglycemia, Hypolipidemic
Institutionalize Patient Related Communication in the Emergency Department of Hamad General Hospital through the Use of Sbar Communication Pattern
Authors: Venugopal Parvathy
Published: July 2019

Introduction

Sbar is a techinique that can be used to facilitate prompt and appropriate communication. It is a way for healthcare proffessionals to communicate effectively. The sbar tool is a memory prompt which helps the medical staff handover, prepare information just before handing over the required details/outcomes/result of the concerned patient from one shift to another shift duty incharge.

Aim/objectives

To increase and starndardize the usage of sbar as a communication tool among the clinical staff in the emergency department of hamad general hospital to 100% by feb 2016.

Methods

The project was done in an iterative four-step continuos improvement method through careful monitoring in various areas of ed to collect the baseline data. Sbar champ were chosen from each area to facilitate & coordinate the project to most of emergency dept. Sbar endorsement form was introduced for the nurses between shifts to notify information. Champion docs, nurse educators & quality reviewers decided on educational sessions to the ed-nurses & physicians. Educational sessions consisted of role play, scenario based and simulation training for the nurses & doctorsto make them understand the relevance of sbar. A monitoring tool was developed for “secret audit” on sbar usage.

Results/outcomes

There has been a spike in the usage of sbar by the nurses & doctors during the endorsement time and between the work schedule. With the help of the charge nurses and sbar champions who regularly change from day to day, careful monitoring has been placed in various areas of the emergency department which has led to such significant achievement. As of now the measurement and the testing has been done with the nurses, physicians, ecg technicians, respiratory therapists and also the quality reviewers. We are soon planning to include ems for the same training and by end of june, we will make sure the whole emergency dept will be talking & reporting in sbar.

Conclusions

Interproffesional communication activity is needed at the entry level for all proffesionals.Sbar is a teachable skill that is recognized by all healthcare workers as a safe effective method of communicating among providers. We will soon spread this communication between units & during transfers also.
Identification of Putative Autism Spectrum Disorder Predisposing Genes by Whole Genome Sequencing & Complex Comparative Genome Analyses in an Extended Family with ASD
Authors: Kambouris Marios , Fadda Abeer , Al-Sarraj Yasser , Ahram Dina , Tomei Sara , Wang Ena , El-Shanti Hatem
Published: July 2019

Autism Spectrum Disorder (ASD) is a lifelong neurodevelopmental disorder characterized by deficits in social communication and interaction, repetitive and restrictive behavior, extensive clinical and etiologic heterogeneity. ASD underlying genetic basis, range from effects of single genes to that of multiple genes and chromosomal regions, hallmarking the multifactorial and complex etiology. While a genetic etiology is identifiable in about one quarter of the cases, in the remaining three quarters it remains elusive. A family with two males affected by ASD was studied to identify the genetic basis of ASD in the family. Two siblings, a brother and his sister, each had a male child with ASD through marriage to their respective unrelated spouses. The first family [F1] has one affected male child; the second [F2] has one affected male and one unaffected female children. The father of F1 and the mother of F2 are brother and sister. No aneuploidy or deletion/duplication defects were detected by Whole-Genome SNP CNV analyses. WGNGS for all members, comparative genome analyses and data mining are as follows: [Only exonic variants considered, prioritized according to increasing population frequency (0–1%), damaging effects according to mutation prediction models and will be presented in table format]. 1. The two ASD events are unrelated and due to individual de-novo variants. Trio analyses for identified 36 de novo variants in F1 and 32 in F2. Variants in KCNH1, ANKRD36C, FRG2C, LOC12989375 were in common 2. The two ASD events are due to heterozygous variants inherited from the related parents. In F1, 370 father-to-son heterozygous variants, in F2, 398 mother-to-son heterozygous variants identified with 132 in common. 3. The related parents are protected from the damaging effects of ASD predisposing variants transmitted to their respective children by protective variants that were not transmitted, hence ASD in their offspring. Analyses were for heterozygous variants shared among the related parents but not transmitted to their affected children. 4. The non-related parents contributed rare predisposing variants, which in synergy with the inherited variants from the related parents exceed a disease onset threshold in the affected offspring. For F1 mother-to-son heterozygous variant transmission; For F2 father-to-son heterozygous variant transmission examined. Complex comparative genome analyses are required to decipher the genetic basis of ASD in families with multiple affected individuals. WGNGS, analyzed for the exome data, is a powerful tool for studying the genetic causes of ASD producing superior results than exome data in which other enrichment technologies are used. WGNGS, even when analyzed only for the exome data, provides clues to novel ASD risk genes, that can be pursued clinically, bioinformatically and functionally.
A Study to Explore how and where the Population of Qatar Source Health Information
Authors: Choudhury Sopna Mannan , Arora Teresa , Alebbi Seham , Ahmed Lina , Aden Abdi , Agouba Sahar , Shewehy Abeer , Dakroury Youssra , Ahmed Salma , Albahri Afnan
Published: July 2019

Introduction

The levels of chronic disease amongst the Qatari population have increased dramatically in recent years. Whilst these diseases are highly prevalent in Qatar, awareness surrounding the recognition of symptoms and the disease itself are limited. Sourcing accurate information about health conditions is crucial. It is currently unknown how Qatari people source information concerning health problems for themselves as well as others. This information, however, is essential for our understanding so that strategies can be derived to assist the population concerning the various health problems that are encountered. We explored how and where the Qatari population seek information regarding health problems.

Methods

Ethical approval was gained from Hamad Medical Corporation/Weill Cornell Medical College in Qatar Joint Institutional Review Board (14-00017). Adult Qataris 18–85 y were approached at different sites, including educational establishments and shopping malls, and asked to complete an anonymous questionnaire to ascertain basic information concerning demographics, health status, and utilisation of health care services during the past year and sources of health information that individuals access. The data were analysed using SPSS version 23.

Results

A total of 394 questionnaires were completed, with 62% respondents being women. More men rated their health as very good compared to women (60.1% and 53.1%, respectively). However, this was not statistically significant X2(3, 387) =  5.7, p =  0.319.

Overall, more people in Qatar used the Internet as a source of health information (71.1%) than in previous studies in the USA (23.8–53.5%)(1,2). This difference between US and Qatar percentages can be explained by the fast diffusion of Internet use and overall wide spread of technology usage among Qataris (3).

More women (78.7%) than men (60.8%) used the Internet as a source of seeking information about health (X2 (1, 72) =  14.8, p
Thymidylate Kinases as Potential Anti-Cancer and Antibiotic Drug Targets
Authors: Rule Gordon
Published: July 2019

Thymidylate kinases (TMKs) play a central role in the production of nucleotide precursors that are required for the replication of DNA. Consequently, this enzyme is a potential drug target for the discovery of anti-bacterial, anti-fungal, and anti-parasitic drugs. In addition, TMKs are also involved in the activation of prodrugs. In particular, the anti-HIV drug AZT is activated by human TMK (huTMK) and the low efficiency of huTMK towards AZT is a significant problem in the use of AZT in the treatment of HIV. Finally, nucleotide precursors are required in large amounts by cancerous cells, thus the inhibition of huTMK by chemotherapeutic agents may enhanced the arsenal of drugs that are used to treat cancer.

Although there has been some effort to develop inhibitors of TMKs, these efforts have been hampered by the difficulty in performing high throughput screening using compound libraries. In addition, the characterization of TMK-drug complexes has been limited to X-ray diffraction studies which provide static information about the enzyme-drug complex. There have been no attempts to apply high-resolution multi-nuclear NMR techniques to determine the fundamental dynamic properties of these enzymes and how the structure and dynamics of the enzyme are altered by the binding of substrates or inhibitors.

As a preliminary step in characterizing these enzymes by NMR we have over-expressed TMKs from yeast, human, and two pathogens - Plasmodium falciparum and Candida albicans. Expression of these TMKs was optimized by the design of synthetic genes for expression in bacteria. In the case of the human enzyme, we are able to routinely produce 250 mg of the enzyme/L of culture. Preliminary NMR spectra of the yeast, human, and plasmodium enzyme show that the protein is a homo-dimer in solution, as anticipated from X-ray studies. The amide and methyl spectra are well resolved, indicating that resonance assignment by traditional TROSY based methods will be feasible for both the amides and the methyl resonances. In particular the high sensitivity and dispersion of the methyl spectra will facilitate characterization of the dynamic properties of these enzymes by carbon and deuterium relaxation. Ligand induced changes in the dynamics and structure of huTMK in solution will be characterized using NMR methods. These studies will provide additional insights into the inability to huTMK to effectively activate AZT. The entropic component of the thermodynamics of substrate binding to TMK from the parasite that causes malaria will also be characterized by determining dynamic changes by NMR methods.

The development of NMR methods to study these enzymes also provides a method for high throughput screening of compound libraries by detecting chemical shift changes in the NMR spectral of the enzyme due to binding of a potential lead compound.
High Selenium Intake is Associated with Endothelial Dysfunction: Critical Role for Endoplasmic Reticulum Stress
Authors: Agouni Abdelali , Zachariah Matshediso , Maamoun Hatem , Rayman Margaret
Published: July 2019

Selenium is associated with insulin resistance and may therefore affect endothelial function, increasing type II diabetes risk and associated cardiovascular-disease risk. However the underpinning molecular mechanisms involved are not clear. High selenium doses cause apoptosis in some cancer cells through the induction of endoplasmic reticulum (ER) stress response, a mechanism also involved in the pathogenesis of insulin resistance and endothelial dysfunction (ED). Thus we hypothesised that high selenium intake could cause ED through ER stress.

Endothelial cells were treated with selenite (0.5–20 μM) in the presence or absence of the ER chemical chaperone, 4-phenylbutryic acid (PBA). High selenium concentrations (5–10 μM of selenite) compared to physiological concentration (0.5 μM) enhanced mRNA expression of several pro-apoptotic ER stress markers; such as activating transcription factor-4 (ATF4) and CAAA/enhanced-binding homologous protein (CHOP). In addition, Griess assay showed that high selenite treatment (5–20 μM) reduced NO production. Moreover, flow cytometry assays showed that high selenium enhanced ROS production and apoptosis in cells. Finally, supra-nutritional concentrations of selenite increased caspases 3/7 activity in endothelial cells compared to the physiological concentration. Interestingly, the pre-incubation of cells with PBA completely reversed all the effects of high selenium indicating the involvement of ER stress response.

Overall, we show here that high selenium treatment causes endothelial dysfunction and cell death through the activation of ER stress response. These results highlight the importance of a balanced selenium intake in order to achieve maximal health benefits. These findings also underscore the importance to monitor cardiovascular risk development in cancer patients supplemented with high amounts of selenium as part of their chemotherapeutic intervention.
Development and Validation of an Allelic Frequency Database for Qatari Population using 13 Rapidly Mutating Y-Str Multiplex Assay
Authors: Almohammed Eida Khalaf
Published: July 2019

Differentiating male lineages using non-recombining Y-chromosomal genetic markers is highly informative for tracing human migration and for forensic studies. Recently, it has been shown that the level of male lineage resolution can be enhanced by analysing Rapidly Mutating (RM) Y-STRs. The aim of this study was to develop an allelic frequency database for Qatari population to evaluate the resolution power of 13 RM Y-STRs. The overall haplotype diversity (HD) was 100% It was found that the markers which contributed the most toward high HD were DYF399S1 and DYF403S1a/b. Together with their value for paternal male relative differentiation, these RM Y-STRs will be a valuable asset for forensic casework. AMOVA test was performed between Qatari population in comparison to Gulf countries, Middle East, and several worldwide population data sets. FST values were also calculated. Geography was found to account considerably for the pattern of population sub structuring. The RM Y-STR markers showed remarkable haplotype resolution power in the Qatari population, high gene diversity and sufficient robustness for a diverse range of applications.
Dexamethasone-induced MicroRNA Regulation for Pancreatic Cancer Progression
Authors: Abukiwan Alia
Published: July 2019

Pancreatic cancer is one of the leading causes of cancer-related mortality worldwide and is highly therapy-resistant, e.g. toward the standard chemotherapy gemcitabine. Glucocorticoids like dexamethasone (DEX) are often co-medicated to reduce inflammation and side effects of tumor growth and therapy. Our group showed DEX to be a potent stimulator of epithelial to mesenchymal transition (EMT), cancer progression and metastasis, but the underlying mechanisms are poorly understood. MicroRNAs are a group of small non-coding RNAs that post transcriptionally regulate gene expression. In this study, I evaluated the effect of DEX on the microRNA profile of pancreatic cancer cell lines. By microRNA array I observed a deregulation of several miRNAs. The most significantly deregulated miRNA, miR-XYZ was predicted to target key members of the TGFß pathway. Forced expression of this miR-XYZ by liposomal transfection of mimicsresulted in significant repression of TGFß-2 mRNA and protein levels. 3’UTR luciferasereporter- and site-directed mutagenesis assays confirmed TGFß-2 to be a direct target of miR-XYZ. Functionally, I found that miR-XYZ significantly reduced proliferation, migration and colony formation. My preliminarily in vivo data show that miR-XYZ reduces tumor xenografttumor growth and abolishes the teratogenic effect of DEX. I conclude that miR-XYZ is a tumor suppressor gene that inhibits EMT by regulating oncogenes and/or genes that control EMT, and DEX is able to activate EMT by suppressing miR-XYZ.
FPGA Based Image Processing Algorithms (Digital Image Enhancement Techniques) Using Xilinx System Generator
Authors: Alareqi Mohammed Abdulhalim
Published: July 2019

FPGAs has many significant features that serves as a platform for processing real time algorithm. It gives substantially higher performance over programmable Digital Signal Processor (DSPs) and microprocessor. At present, the use of FPGA in research and development of applied digital systems for specific tasks are increasing. This is due to the advantages FPGAs has over other programmable devices. These advantages are high clock frequency, high operations per second, code portability, code libraries reusability, low cost, parallel processing, Capability of interacting with high or low interfaces, security and Intellectual Property (IP).

This paper presents concept of hardware digital image processing algorithms using field programmable gate array (FPGA). It focus on implementation an efficient architecture for image processing algorithms like image enhancement (point processing techniques (by using fewest possible System Generator Blocks. In this paper, Modern approach of ‘Xilinx System Generator’ (XSG) is used for system modeling and FPGA programming. Xilinx System Generator is a tool of matlab that generates bit stream file (*.bit), Netlist, timing and power analysis. Performance of these architectures implemented in FPGA card XUPV5-LX110T.
A Distributed and Adaptive Graph Simulation System
Authors: Nilangekar Pooja , Hammoud Mohammad
Published: July 2019

Large-scale graph processing is becoming central to our modern life. For instance, graph pattern matching (GPM) can be utilized to search and analyze social graphs, biological data and road networks, to mention a few. Conceptually, a GPM algorithm is typically defined in terms of subgraph isomorphism, whereby it seeks to find subgraphs in an input data graph, G, which are similar to a given query graph, Q. Although subgraph isomorphism forms a uniquely important class of graph queries, it is NP-complete and very restrictive in capturing sensible matches for emerging applications like software plagiarism detection, protein interaction networks, and intelligence analysis, among others. Consequently, GPM has been recently relaxed and defined in terms of graph simulation. As opposed to subgraph isomorphism, graph simulation can run in quadratic time, return more intuitive matches, and scale well with modern big graphs (i.e., graphs with billions of vertices and edges). Nonetheless, the current state-of-the-art distributed graph simulation systems still rely on graph partitioning (which is also NP-complete), induce significant communication overhead between worker machines to resolve local matches, and fail to adapt to various complexities of query graphs.

In this work, we observe that big graphs are not big data. That is, the largest big graph that we know of can still fit on a single physical or virtual disk (e.g., 6TB physical disks are cheaply available nowadays and AWS EC2 instances can offer up to 24 ×  2048GB virtual disks). However, since graph simulation requires exploring the entire input big graph, G, and naturally lacks data locality, existing memory capacities can get significantly dwarfed by G's size. As such, we propose GraphSim, a novel distributed and adaptive system for efficient and scalable graph simulation. GraphSim precludes graph partitioning altogether, yet still exploits parallel processing across cluster machines. In particular, GraphSim stores G at each machine but only matches an interval of G's vertices at the machine. All machines are run in parallel and each machine simulates its interval locally. Nevertheless, if necessary, a machine can inspect remaining dependent vertices in G to fully resolve its local matches without communicating with any other machine. Hence, GraphSim does not shuffle intermediate data whatsoever. In addition, it attempts not to overwhelm the memory of any machine via employing a mathematical model to predict the best number of machines for any given query graph, Q, based on Q's complexity, G's size and the memory capacity of each machine. Subsequently, GraphSim renders adaptive as well. We experimentally verified the efficiency and the scalability of GraphSim over private and public clouds using real-life and synthetic big graphs. Results show that GraphSim can outperform the current fastest distributed graph simulation system by several orders of magnitude.
Road Traffic Accidents in Kuwait (Triangulation Method Study)
Authors: Ali Alsaleh Amer
Published: July 2019

The study has revealed the pattern and trends of motor traffic accidents in Kuwait City from 2010 to 2011. It shows that the accident occurrence was increasing every year, passengers and pedestrians are always at highest risk of being injured or killed on the road, young males are highly prone to motor traffic accidents. The study has also identified qualitatively (by interviews) that the technical element of the highway construction, irresponsibility, poor management, cell phones, alcohol and drugs, age of the victims and poor condition of services as the important risk factors associating to the cause of traffic accidents in Kuwait. In order to reduce traffic accidents in Kuwait City, it is recommended that the government should review legislation regarding employment of drivers. Working conditions of police force should be improved, public road safety campaigns should be conducted, and new driving license system should be imposed. The use of cell phones while driving should be restricted. The hospital and police record keeping should be strengthened, the hospital staff, traffic police and ambulance personnel should be considered for intensive training on emergency and preparedness, and regular vehicle inspection should be introduced in Kuwait City.
Epidemiological and Clinical Profiles of Patients with Acute Respiratory Distress Syndrome Admitted to Medical Intensive Care in Qatar: A Retrospective Analysis of the Data Registry for the Year 2015
Authors: Ibrahim Abdulsalam Saif , Akkari Abdel-Rauof Mahmud , Raza Tasleem , Hassan Ibrahim Fawzy , Akbar Anzila , Alatoum Ibrahim
Published: July 2019

Background: Although acute respiratory distress syndrome (ARDS) is a common reason for admission to intensive care units, limited information is available about the epidemiological and clinical characteristics of these patients in Middle Eastern countries. Qatar is a high per capita income country with a large multinational expatriate population. Hamad General Hospital is our main tertiary referral center with the largest medical intensive care unit (MICU). Method: A retrospective cross-sectional study was conducted to extract data from the MICU registry for 101 patients aged >14 years who were admitted with ARDS from January 2015 to December 2015. Results: In 2015, a total of 101 (14.8%) of 682 patients admitted to MICU were diagnosed with ARDS. Males comprised 71.3% and females 28.7%. The mean age of the study population was 44.96 ± 17.97 years. Community-acquired bacterial and viral pneumonia were the most common reasons for ARDS. Crude mortality rate was 35%. The mean age of survivors was 42.09 ± 13.58 years compared with 50.36 ± 16.84 years of non-survivors (p = 0.008). Mortality was associated with increasing age, the Acute Physiologic Assessment and Chronic Health Evaluation II severity score, lower P/F ratio, higher Murray's score, higher PCO2, lower pH, and circulatory support with vasopressors. Preexisting comorbidities did not contribute to high mortality. No difference in mortality was noted with higher versus lower positive end expiratory pressure. The prone position was used in 8% of the cases. Twenty-seven (27%) patients had undergone salvage therapy with extracorporeal membrane oxygenation (ECMO) that resulted in a survival rate of 44%. ARDS was associated with acute renal failure requiring dialysis in 28.7% of the cases, pneumothoraces in 4%, ventilator-associated pneumonia in 7.9%, and central line-associated bloodstream infection in 2%. ARDS led to a prolonged length of stay compared with the average length of stay in MICU. Conclusion: Community-acquired bacterial and viral pneumonia were the most common causes of ARDS at our center. Critical care outcome correlated with the severity of the disease. ECMO was used as salvage therapy in our center.