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Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using MAX phase Cr2TialC2 saturable absorber

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Optoelectronics letters 2025年第1期21卷 7-12页

作者： Ahmed shakir al-HITI Hiba HAssAN Department of Electrical Engineering Faculty of Engineering University of Anbar Department of laser and Optoelectronics Engineering University of Technology-Iraq

We demonstrated a new type of MAX phase material, chromium titanium aluminum carbide（Cr2TialC2） polymer film, to generate a passively Q-switched erbium-doped fiber laser（EDFl）. The film thickness was measured to be around 45 μm, which was fabricated using the embedding method with polyvinyl.alcohol（PVA） polymer as hoster. The saturable absorber（sA） film demonstrates a dual-wavelength passively Q-switched EDFl which operates at 1 531 nm and 1 560.19 nm, respectively. The Q-switching pulse duration could be varied from 2.46 μs to 770 ns, while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 mW. The maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW, respectively.

关键词： saturable absorbers

Decoding molecular mechanisms:brain aging and alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay ali syed Hammad Qaiser Mohammad Uzair Khalid al-Regaiey Roaa Khallaf lubna Abdullah Mohammed albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish sBhatti shahid Bashir Atta-ur-Rahman school of Applied Biosciences(AsAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly alzheimer's disease.

关键词： alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Comparative chemical sensor for detection of chromium(Ⅵ) in aqueous solution

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Optoelectronics letters 2025年第1期21卷 21-27页

作者： sura H.al-REKABI A.A.alWAHIB Electrical Technique Department Al Suwayrah Technical Institute Middle Technical University laser and Optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as chromium（Cr） has been investigated. One of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. surface plasmon resonance（sPR） technique has attracted huge research interest in detecting heavy metals specifically. In this s.udy, three types of prism-based sPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（TiO2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag, Au/PANI nanofibers and Au/TiO2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Revisiting cerebral endothel.al cells in alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is famil.al,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： alzheimer Aβ cerebral

Emerging structures and dynamic mechanisms ofγ-secretase for alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset famil.al alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating famil.al alzheimer’s disease and the more common late-onset alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of famil.al alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent s.udies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of famil.al alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future s.udies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on famil.al alzheimer’s disease mutations

关键词： alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Complementary roles of gl.al cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2917-2918页

作者： leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating

Plant communities and reproductive phenology in mountainous regions of northern libya

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Journal of Forestry Research 2017年第4期28卷 741-761页

作者： Ahmad K. Hegazy Hanan F. Kabiel s.ud l. al-rowaily lesley lovett-Doust Abd El-Nasser s. al Borki Department of Botany and Microbiology Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Plant Production College of Food and Agricultural SciencesKing Saud UniversityRiyadhSaudi Arabia Department of Biology and Chemistry Nipissing UniversityNorth BayONCanada Department of Botany Faculty of Sciences and ArtsUniversity of BenghaziAgdabiaLibya

Within the semi-desert landscape of northern libya, two sub-humid escarpments occur: al-Akhdar in the east and Nafusa (Jabal.al-Gharbi) in the west. This s.udy compares plant communities in the two regions, which are along an elevation gradient, in terms of species composition and diversity, frequency of different Raunkiaer life forms, and reproductive phenology. The two regions differed in species composition and life-form frequency between regions and between elevation zones within each region. Patterns were associated with the lower rainfall and lower moisture-holding capacity of soils at Nafusa, resulting in more xeric conditions. Only 13% of species were shared between the two regional landscapes. species diversity, life-form frequency, and duration of the flowering-fruiting phenophase were all affected by elevation above sea level. The duration of flowering and fruiting in spring and fall was associated with environmental conditions, although there were different thresholds in the two regions. There was both a spring and fall episode of flowering at Nafusa, but only spring flowering at al-Akhdar. It is anticipated that there will be a gradual shift of plant communities to higher elevations and loss of certain sensitive species in response to ongoing climate change.

关键词： altitudinal gradient Raunkiaer life forms Reproductive phenology southern Mediterranean

Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

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Neural Regeneration Research 2025年第10期20卷 2913-2914页

作者： William J.Flerlage Mark l.Dell’Acqua Brian M.Cox Fereshteh s.Nugent Uniformed services University of the Health sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

On the Optimization of Performance of Hg_xCd_(1-x)s Based Electrochemical Photosensing Cell

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稀有金属材料与工程 2012年第S1期41卷 43-46页

作者： lendave s al P Pingale P Cl P Deshmukh l P Thin Film and solar s.udies Research laboratory Department of Physics(Appli.Elect.)Solapur UniversitySolapur-413255M.S.India

Chemical growth process that favours deposition of semiconductor materials from a liquid phase was used to obtain Cds and HgxCd1-xs(0≤x≤0.25)photosensitive thin film electrodes on the stainless steel *** deposition of these series of thin films was carried out under the optimized conditions of temperature(60℃),time(90 min)and pH(10.8±0.2).These films were then employed as photosensitive electrode in an electrochemical photosensing cell consisting of sulphide/polysulphide redox electrolyte and a graphite counter *** cells were illuminated by an input illumination intensity of 13 mW/cm 2 and the cell characteristic parameters namely photocurrent(Iph),photo voltage(Vph),the quantum conversion efficiency(η%)and fill factor(ff %)have been *** Vph and Iph have been found to be boosted as the electrode composition is *** conversion efficiency and fill factor enhanced from 0.52%to 1.30%and 31.8%to 37.8%,respectively for the change of electrode composition from 0 to *** of junction ideality factor(nd)showed recombination mechanism at the electrode-electrolyte *** height measurements gave Pool-Frenkel type conduction *** flat band potentials(Vfb)were determined for all the cells and found to be enhanced with x up to 0.08 and then decreased for further increase in *** lighted junction quality factor(nl)is increased from 1.49 to 2.94 as the photoelectrode composition(x)was varied from 0 to *** barrier heights(B)at the electrode/electrolyte interfaces were also *** is found that B is higher for a cell of electrode composition equal to *** spectral s.udies on these cells showed the cut off wavelength(λc)shifted from 530 nm to 800 *** transient response s.udies showed presence of surface states at the interface that causes Fermi-level ***,performance of the electrochemical photosensing cell is found to be improved after Hg-corboration in Cds and is optimum at x= 0.0

关键词： electrochemical cell photosensing fill factor interface states photovoltage photocurrent