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Article ; Online: Exploring the Influence of Perceived Ingroup and Outgroup Threat on Quality of Life in a Region Impacted by Protracted Conflict.

Abuelaish, Izzeldin / Siddiqua, Ayesha / Yousufzai, Susan J / Barakat, Caroline

International journal of environmental research and public health

2023 Volume 20, Issue 16

Abstract: While the detrimental effects of protracted political conflict on the wellbeing of Palestinians living in the occupied Palestinian territory (oPt) are generally recognized, the impact of perceived threat on quality of life (QoL) faced from within their ... ...

Abstract	While the detrimental effects of protracted political conflict on the wellbeing of Palestinians living in the occupied Palestinian territory (oPt) are generally recognized, the impact of perceived threat on quality of life (QoL) faced from within their community (ingroup; Palestinians) and from the outgroup (Israelis) is unexplored. This cross-sectional study examined the following: (1) The status of perceptions of QoL on four domains measured by the World Health Organization Quality of Life (WHOQoL-Bref) instrument, physical health, psychological health, social relationships, and environment, among Palestinian adults (
MeSH term(s)	Adult ; Humans ; Quality of Life ; Cross-Sectional Studies ; Arabs ; Existentialism
Language	English
Publishing date	2023-08-18
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2175195-X
ISSN	1660-4601 ; 1661-7827
ISSN (online)	1660-4601
ISSN	1661-7827
DOI	10.3390/ijerph20166599
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Book ; Online: Stochastic Policy Gradient Methods

Fatkhullin, Ilyas / Barakat, Anas / Kireeva, Anastasia / He, Niao

Improved Sample Complexity for Fisher-non-degenerate Policies

2023

Abstract: Recently, the impressive empirical success of policy gradient (PG) methods has catalyzed the development of their theoretical foundations. Despite the huge efforts directed at the design of efficient stochastic PG-type algorithms, the understanding of ... ...

Abstract	Recently, the impressive empirical success of policy gradient (PG) methods has catalyzed the development of their theoretical foundations. Despite the huge efforts directed at the design of efficient stochastic PG-type algorithms, the understanding of their convergence to a globally optimal policy is still limited. In this work, we develop improved global convergence guarantees for a general class of Fisher-non-degenerate parameterized policies which allows to address the case of continuous state action spaces. First, we propose a Normalized Policy Gradient method with Implicit Gradient Transport (N-PG-IGT) and derive a $\tilde{\mathcal{O}}(\varepsilon^{-2.5})$ sample complexity of this method for finding a global $\varepsilon$-optimal policy. Improving over the previously known $\tilde{\mathcal{O}}(\varepsilon^{-3})$ complexity, this algorithm does not require the use of importance sampling or second-order information and samples only one trajectory per iteration. Second, we further improve this complexity to $\tilde{ \mathcal{\mathcal{O}} }(\varepsilon^{-2})$ by considering a Hessian-Aided Recursive Policy Gradient ((N)-HARPG) algorithm enhanced with a correction based on a Hessian-vector product. Interestingly, both algorithms are $(i)$ simple and easy to implement: single-loop, do not require large batches of trajectories and sample at most two trajectories per iteration; $(ii)$ computationally and memory efficient: they do not require expensive subroutines at each iteration and can be implemented with memory linear in the dimension of parameters. Comment: This work was initially submitted in October 2022
Keywords	Computer Science - Machine Learning ; Mathematics - Optimization and Control ; 90C26 ; 90C15 ; G.1.6
Subject code	510
Publishing date	2023-02-03
Publishing country	us
Document type	Book ; Online
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Article ; Online: Effect of Copper and Zinc Ions on Biochemical and Molecular Characteristics of Calcium Oxalate Renal Stones: a Controlled Clinical Study.

Taha, Shaimaa A Y / Shokeir, Ahmed A / Mortada, Wael I / Awadalla, Amira / Barakat, Lamiaa A A

Biological trace element research

2023 Volume 202, Issue 2, Page(s) 410–422

Abstract: Contradictory results are existed in the literature regarding the impact of trace elements on the pathogenesis of calcium oxalate (CaOx) stone patients. Therefore, the aim of our study was to investigate the effect of Cu and Zn on biochemical and ... ...

Abstract	Contradictory results are existed in the literature regarding the impact of trace elements on the pathogenesis of calcium oxalate (CaOx) stone patients. Therefore, the aim of our study was to investigate the effect of Cu and Zn on biochemical and molecular characteristics of CaOx stones. Plasma and urine concentrations of Cu and Zn in 30 CaOx stones patients and 20 controls were determined by flame atomic absorption spectrometry (FAAS). Urinary levels of citric acid and oxalate were measured by commercial spectrophotometric kits. Blood levels of glutathione reduced (GSH) and catalase (CAT) were determined as markers of antioxidant activity, while blood malondialdehyde (MDA) and urine level of nitric oxide (NO) were used to assess oxidative stress. Gene expression of MAPk pathway (ERK, P38, and JNK) were estimated. The plasma and urine levels of Cu were significantly increased in the patient group compared to those of controls, while the levels of Zn were decreased. Excessive urinary excretion of citric acid and oxalate were found among CaOx stone patients. The GSH and CAT concentration were significantly reduced in CaOx stones patients compared to healthy group. The plasma MDA and urine NO concentration were significantly increased in CaOx stones patients compared to control group. The expressions of the studied genes were significantly increased in CaOx stones patients. These findings suggest that alteration in Cu and Zn might contribute to pathogenesis of CaOx patients through oxidative stress and MAPK pathway genes (ERK, P38 and JNK).
MeSH term(s)	Humans ; Calcium Oxalate/urine ; Copper ; Zinc ; Kidney Calculi ; Oxalates ; Citric Acid ; Ions
Chemical Substances	Calcium Oxalate (2612HC57YE) ; Copper (789U1901C5) ; Zinc (J41CSQ7QDS) ; Oxalates ; Citric Acid (2968PHW8QP) ; Ions
Language	English
Publishing date	2023-05-16
Publishing country	United States
Document type	Journal Article
ZDB-ID	445336-0
ISSN	1559-0720 ; 0163-4984
ISSN (online)	1559-0720
ISSN	0163-4984
DOI	10.1007/s12011-023-03686-0
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Book ; Online: Reinforcement Learning with General Utilities

Barakat, Anas / Fatkhullin, Ilyas / He, Niao

Simpler Variance Reduction and Large State-Action Space

2023

Abstract: We consider the reinforcement learning (RL) problem with general utilities which consists in maximizing a function of the state-action occupancy measure. Beyond the standard cumulative reward RL setting, this problem includes as particular cases ... ...

Abstract	We consider the reinforcement learning (RL) problem with general utilities which consists in maximizing a function of the state-action occupancy measure. Beyond the standard cumulative reward RL setting, this problem includes as particular cases constrained RL, pure exploration and learning from demonstrations among others. For this problem, we propose a simpler single-loop parameter-free normalized policy gradient algorithm. Implementing a recursive momentum variance reduction mechanism, our algorithm achieves $\tilde{\mathcal{O}}(\epsilon^{-3})$ and $\tilde{\mathcal{O}}(\epsilon^{-2})$ sample complexities for $\epsilon$-first-order stationarity and $\epsilon$-global optimality respectively, under adequate assumptions. We further address the setting of large finite state action spaces via linear function approximation of the occupancy measure and show a $\tilde{\mathcal{O}}(\epsilon^{-4})$ sample complexity for a simple policy gradient method with a linear regression subroutine. Comment: 48 pages, 2 figures, ICML 2023, this paper was initially submitted in January 26th 2023
Keywords	Computer Science - Machine Learning ; Mathematics - Optimization and Control
Subject code	519
Publishing date	2023-06-02
Publishing country	us
Document type	Book ; Online
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Book ; Online: Learning Zero-Sum Linear Quadratic Games with Improved Sample Complexity and Last-Iterate Convergence

Wu, Jiduan / Barakat, Anas / Fatkhullin, Ilyas / He, Niao

2023

Abstract: ... algorithm that seeks NE of zero-sum LQ games; (ii) in the model-free setting, we establish a~$\widetilde ...

Abstract	Zero-sum Linear Quadratic (LQ) games are fundamental in optimal control and can be used (i)~as a dynamic game formulation for risk-sensitive or robust control and (ii)~as a benchmark setting for multi-agent reinforcement learning with two competing agents in continuous state-control spaces. In contrast to the well-studied single-agent linear quadratic regulator problem, zero-sum LQ games entail solving a challenging nonconvex-nonconcave min-max problem with an objective function that lacks coercivity. Recently, Zhang et al. showed that an~$\epsilon$-Nash equilibrium (NE) of finite horizon zero-sum LQ games can be learned via nested model-free Natural Policy Gradient (NPG) algorithms with poly$(1/\epsilon)$ sample complexity. In this work, we propose a simpler nested Zeroth-Order (ZO) algorithm improving sample complexity by several orders of magnitude and guaranteeing convergence of the last iterate. Our main results are two-fold: (i) in the deterministic setting, we establish the first global last-iterate linear convergence result for the nested algorithm that seeks NE of zero-sum LQ games; (ii) in the model-free setting, we establish a~$\widetilde{\mathcal{O}}(\epsilon^{-2})$ sample complexity using a single-point ZO estimator. For our last-iterate convergence results, our analysis leverages the Implicit Regularization (IR) property and a new gradient domination condition for the primal function. Our key improvements in the sample complexity rely on a more sample-efficient nested algorithm design and a finer control of the ZO natural gradient estimation error utilizing the structure endowed by the finite-horizon setting.
Keywords	Electrical Engineering and Systems Science - Systems and Control ; Computer Science - Computer Science and Game Theory ; Computer Science - Machine Learning
Subject code	519
Publishing date	2023-09-08
Publishing country	us
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Diffuse Sarcoidosis Presenting as Metastatic Malignant Disease-Like Picture: A Case Report.

Alelaumi, Ahmad / Alfawareh, Mohammad / Althunibat, Ismail / Al-Ibraheem, Akram / Barakat, Fareed

International journal of spine surgery

2023 Volume 17, Issue 5, Page(s) 661–669

Abstract: Background: Sarcoidosis is a chronic inflammatory condition characterized by the formation of granulomas, which can impact various organs and tissues throughout the body. It frequently affects the lungs and mediastinal lymph nodes. The presence of ... ...

Abstract	Background: Sarcoidosis is a chronic inflammatory condition characterized by the formation of granulomas, which can impact various organs and tissues throughout the body. It frequently affects the lungs and mediastinal lymph nodes. The presence of multiple lytic lesions in the spine can be concerning, as it may indicate an undiagnosed or advanced metastatic malignancy. We present an unusual and interesting case of sarcoidosis in which the patient had multiple lytic lesions in the vertebrae, which resembled the presentation of metastatic malignant disease. Case description: A 46-year-old woman with no known medical history presented to our cancer center complaining of neck pain and bilateral shoulder pain. After conducting extensive investigations, an atypical manifestation of sarcoidosis was identified. The patient was administered corticosteroids, which effectively managed the disease and resulted in a substantial improvement in her symptoms. Conclusions: Before considering surgical intervention or radiotherapy for cases involving multiple lytic lesions in the spine with an unknown primary cause, it is essential to conduct a comprehensive diagnostic evaluation. This thorough work-up is necessary to establish a clear diagnosis. If the patient's neurological condition permits, a complete assessment can help prevent substantial morbidity. In certain cases, a patient's condition may involve an atypical manifestation of pathologies that are not related to metastatic diseases, suggesting that simpler treatment approaches might be adequate.
Language	English
Publishing date	2023-07-24
Publishing country	Netherlands
Document type	Journal Article
ISSN	2211-4599
ISSN	2211-4599
DOI	10.14444/8523
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Article ; Online: Development of chia gum/alginate-polymer support for horseradish peroxidase immobilization and its application in phenolic removal.

Mohamed, Saleh A / Elsayed, Alshaimaa M / Salah, Hala A / Barakat, Amal Z / Bassuiny, Roqaya I / Abdel-Mageed, Heidi M / Abdel-Aty, Azza M

Scientific reports

2024 Volume 14, Issue 1, Page(s) 1362

Abstract: Chia gum's molecular structure with distinctive properties as well as the alginate-based hydrogel's three-dimensionally cross-linked structure can provide a potent matrix for immobilization of enzyme. Herein, chia gum (CG)/alginate (A)-polymeric complex ... ...

Abstract	Chia gum's molecular structure with distinctive properties as well as the alginate-based hydrogel's three-dimensionally cross-linked structure can provide a potent matrix for immobilization of enzyme. Herein, chia gum (CG)/alginate (A)-polymeric complex was synthesized and employed as a support material for the immobilization of horseradish peroxidase (HRP). HRP was successfully immobilized on the developed ACG-polymeric support, and the highest immobilization recovery (75%) was observed at 1.0% CG and 2% A, pH 7.0, and 50 units of the enzyme. The structure, morphology, and thermal properties of the prepared ACG-HRP were demonstrated using Fourier Transform Infrared (FTIR), Scanning Electron Microscope, and Thermogravimetric (TGA) analyses. ACG-HRP showed a good reusability (60%) over ten reuses. The immobilized ACG-HRP displayed an acidic pH optimum (6.0), a higher temperature optimum (50 °C), and improved thermal stability (30-50 °C) compared to the soluble HRP at pH 7.0, 40 °C and (30-40 °C), respectively. ACG-HRP has a lower affinity for hydrogen peroxide (H
MeSH term(s)	Enzymes, Immobilized/chemistry ; Enzyme Stability ; Polymers ; Temperature ; Horseradish Peroxidase/metabolism ; Hydrogen Peroxide ; Phenol ; Urea ; Hydrogen-Ion Concentration
Chemical Substances	Enzymes, Immobilized ; Polymers ; Horseradish Peroxidase (EC 1.11.1.-) ; Hydrogen Peroxide (BBX060AN9V) ; Phenol (339NCG44TV) ; Urea (8W8T17847W)
Language	English
Publishing date	2024-01-16
Publishing country	England
Document type	Journal Article
ZDB-ID	2615211-3
ISSN	2045-2322 ; 2045-2322
ISSN (online)	2045-2322
ISSN	2045-2322
DOI	10.1038/s41598-024-51566-x
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Article ; Online: Improved rock phosphate dissolution from organic acids is driven by nitrate assimilation of bacteria isolated from nitrate and CaCO3-rich soil.

Garcia-Sanchez, Mercedes / Bertrand, Isabelle / Barakat, Abdellatif / Zeroual, Youssef / Oukarroum, Abdallah / Plassard, Claude

PloS one

2023 Volume 18, Issue 3, Page(s) e0283437

Abstract: Until now, the solubilization capacities of insoluble mineral P by soil microorganisms have been screened in vitro with media containing NH4+ as a nitrogen source. This presence of NH4+ will lead to an acidification of the medium responsible for the ... ...

Abstract	Until now, the solubilization capacities of insoluble mineral P by soil microorganisms have been screened in vitro with media containing NH4+ as a nitrogen source. This presence of NH4+ will lead to an acidification of the medium responsible for the solubilization of the insoluble P. However, besides proton release, the production of organic acids can play a very important role in the release of free P. This physiological mechanism can largely depend on the source of nitrogen (NH4+vs NO3-) assimilated by the bacteria but the influence of the N source on the production of organic acids has yet to be studied. Our aim was to investigate if the N source assimilated by bacteria and the soil characteristics such as the dominant N source (NH4+vs NO3-) and CaCO3 contents might influence the bacterial capacities to solubilize rock phosphate. To fill this objective, we screened the capacity of bacteria isolated from 3 soils to solubilize rock phosphate in vitro in presence of NH4+or NO3-. Then, we selected the most efficient bacterial strains to identify and quantify the release of organic anions into the medium. Among the two hundred and forty-three bacterial strains isolated from the 3 soils, nine and seven isolates were identified with the highest % rock phosphate-solubilization values with NH4+ or NO3- as the sole N-source. Only one strain was able to release free Pi with NH4+ or NO3- as the sole N-source. The most predominant organic acids released by almost all isolates were gluconic acid, lactic acid, glycolic acid, acetic acid, formic acid and pyruvic acid regardless the N-source. However, with NO3- as source of N, the highest concentrations on those acids were found together with the highest release of free Pi into the medium. Molecular analysis of 16S rRNA indicated that almost all strains belonged to Bacillus and Paenibacillus genera. The PCA analysis between soil properties and bacterial capacities to release organic acids and free Pi also revealed that soil factors such as CaCO3 and soil NO3- content positively influenced the release of organic acids by bacteria grown in vitro. Our results concluded that the bacterial rock phosphate-solubilization was intimately related to organic acids production which in turn seemed to be driven by the assimilation of NO3- by bacteria. Therefore, the N-source might be considered a key factor to take into consideration during the screening and selection of suitable strains involved in the P-solubilization.
MeSH term(s)	Phosphates ; Nitrates ; Soil ; Solubility ; RNA, Ribosomal, 16S/genetics ; Calcium Carbonate ; Bacteria ; Nitrogen ; Soil Microbiology
Chemical Substances	Phosphates ; Nitrates ; Soil ; RNA, Ribosomal, 16S ; Calcium Carbonate (H0G9379FGK) ; Nitrogen (N762921K75)
Language	English
Publishing date	2023-03-24
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2267670-3
ISSN	1932-6203 ; 1932-6203
ISSN (online)	1932-6203
ISSN	1932-6203
DOI	10.1371/journal.pone.0283437
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Article: Recurrent Lumbar Disc Herniation: Does Transforaminal Lumbar Interbody Fusion Lead to Better Clinical and Radiological Outcomes than Redo-Discectomy?

Mosaad, Mohamed / Khozamy, Ali / Barakat, Ahmed Samir / Emran, Ihab / Elmeligy, Yasser / Abulhamd, Alaa

Asian spine journal

2023 Volume 17, Issue 5, Page(s) 862–869

Abstract: Study design: randomized, prospective, and level I clinical study.: Purpose: To compare the clinical outcomes and radiological findings of revision discectomy alone versus revision discectomy with fusion as surgical treatment for recurrent lumbar ... ...

Abstract	Study design: randomized, prospective, and level I clinical study. Purpose: To compare the clinical outcomes and radiological findings of revision discectomy alone versus revision discectomy with fusion as surgical treatment for recurrent lumbar disc herniation (RDH). Overview of literature: RDH is a common complication following a primary discectomy. The optimal surgical procedure for RDH is still debated. Methods: Sixty patients with RDH were randomly divided into two equal groups: the first group underwent revision discectomy alone and the second underwent revision discectomy with fusion. The primary outcomes evaluated were Visual Analog Scale (VAS) for low back and limb pains, Oswestry Disability Index (ODI), disc height indexes, foraminal height index, and disc height subsidence. Secondary outcomes included operative time, blood loss, postoperative hospital stay, and complications. Results: Revision discectomy with fusion showed superior pain relief and improved functional outcomes, including better VAS scores for both back and leg pain and ODI at 24-month follow-up. Additionally, it restored the stability of the spine better with lower disc height subsidence without significant complications. However, these advantages came at the cost of increased blood loss and longer operative time and hospital stays. Conclusions: Revision discectomy with fusion is recommended for RDH; however, the choice of the procedure should be made caseby- case basis, considering many factors related to the patient and surgical facilities.
Language	English
Publishing date	2023-08-14
Publishing country	Korea (South)
Document type	Journal Article
ZDB-ID	2559763-2
ISSN	1976-7846 ; 1976-1902
ISSN (online)	1976-7846
ISSN	1976-1902
DOI	10.31616/asj.2022.0210
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Article ; Online: Etrolizumab as an induction and maintenance therapy for ulcerative colitis: A systematic review and meta-analysis of randomized controlled trials.

Saleh, Othman / Abuelazm, Mohamed T / Mohamed, Islam / Ramadan, Alaa / Assaf, Mohammad / Alzoubi, Ahmad / AlBarakat, Majd M / Abdelazeem, Basel

JGH open : an open access journal of gastroenterology and hepatology

2024 Volume 8, Issue 4, Page(s) e13056

Abstract: Background and aim: Etrolizumab is a gut-targeted anti-β7 integrin monoclonal antibody. However, the evidence of etrolizumab efficacy and safety in ulcerative colitis remains inconclusive. Therefore, we aim to evaluate the safety and efficacy of ... ...

Abstract	Background and aim: Etrolizumab is a gut-targeted anti-β7 integrin monoclonal antibody. However, the evidence of etrolizumab efficacy and safety in ulcerative colitis remains inconclusive. Therefore, we aim to evaluate the safety and efficacy of etrolizumab as an induction and maintenance therapy for active moderate to severe ulcerative colitis. Methods: We synthesized randomized controlled studies (RCTs) from MEDLINE, Scopus, EMBASE, PubMed, Web of Science, and Cochrane Library until April 2023. The risk ratio (RR) for dichotomous outcomes with the corresponding 95% confidence interval (CI) was used. The study protocol was registered in PROSPERO with ID: CRD42023437040. Results: Five RCTs with 1849 participants were included. The etrolizumab group had a significant clinical response (RR: 1.28 with 95% CI [1.08, 1.51], Conclusion: Etrolizumab shows its effectiveness as both an induction and maintenance therapy for moderate or severe UC. The findings demonstrate its positive impact on clinical, endoscopic, and histologic remission rates. Regarding safety, other than any side effects, etrolizumab showed a good safety than a placebo.
Language	English
Publishing date	2024-04-02
Publishing country	Australia
Document type	Journal Article ; Review
ISSN	2397-9070
ISSN (online)	2397-9070
DOI	10.1002/jgh3.13056
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