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Appraisal of active tectonics in Hindu Kush:Insights from DEM derived geomorphic indices and drainage analysis

Geoscience Frontiers 2012年第4期3卷 407-428页

作者： Syed Amer mahmood Richard Gloaguen Remote Sensing Group Institute of GeologyFreiberg University of Mining and TechnologyBernhard V.Cotta Str209599 Freiberg(Saxony)Germany Department of Space Science University of the PunjabQuaid-e-Azam Campus54590Lahore(Punjab)Pakistan Remote Sensing Group Institute of GeologyFreiberg University of Mining and TechnolohyBernhard V.Cotta Str.209599 Freiberg(Saxony)Germany

Landscapes in tectonically active Hindu Kush （NW Pakistan and NE Alghanistanl result from a complex integration of the effects of vertical and horizontal crustal block motions as well as erosion and deposition processes. Active tectonics in this region have greatly influenced the drainage system and geomorphic expressions. The study area is a junction of three important mt^unlain ranges （Hindu Kush-Karakorunl-Himalayas） and is thus an ideal natural laboratory to investigate the relative tectonic activity resulting from the India-Eurasia collision. We evaluate active tectonics using DEM derived drainage network and geomorphic indices hypsometric integral （Hl）. stream-length gradient （SL）, fractal dimension （FD）, basin asymmetry factor （AF）, basin shape index （B,）, valley floor width to wllley height ratio （Vf） and motmtain front sinuosity （Star）. The results obtained from these indices were combined to yield an index of relative active tectonics （IRAT） using GIS. The average of the seven measured geomorphic indices was used to ewfluate the distri- bution of relative tectonic activity in the study area. We defined tour classes to define the degree of rela- tive tectonic activity： class 1 very high （1.0 ≤ IRAT 〈 1.3）; class 2 high （1.3 ≥ IRAT 〈 1.5）： class 3--moderate （1.5 〉 IRAT 〈 1.8）; and class 4--low （1.8 〉 IRAT）. In view of the results, we conclude that this combined approach allows the identification of the highly deformed areas related to active tectonics. Landsat imagery and field observations also evidence the presence of active tectonics based on the deflected streams, deformed landforms, active mountain fronts and triangular facets. The indicative values of IRAT are consistent with the areas of known relative uplift rates, landforms and geology.

关键词： Active tectonics:Geomorphic indices:IRAT (index of relativeactive tectonics):Hindu Kush:Pakistan--Alghanistan

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Limb-girdle muscular dystrophy subtypes First-reported cohort from northeastern China

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Neural Regeneration Research 2013年第20期8卷 1907-1918页

作者： Omar Abdulmonem mahmood Xinmei Jiang Qi Zhang Department of Neurology Affiliated First Hospital of Jilin University Department of Neuromedicine Mosul Medical College

The relative frequencies of different subtypes of limb-girdle muscular dystrophies vary widely among different populations. We estimated the percentage of limb-girdle muscular dystrophy subtypes in Chinese people based on 68 patients with limb-girdle muscular dystrophy from the Myology Clinic, Neurology Department, First Hospital of Jilin University, China. A diagnosis of calpainopathy was made in 12 cases （17%）, and dysferlin deficiency in 10 cases （15%）. Two biopsies revealed α-sarcoglycan deficiency （3%）, and two others revealed a lack of caveolin-3 （3%）. A diagnosis of unclassified limb-girdle muscular dystrophy was made in the remaining patients （62%）. The ap-pearances of calpain 3- and dysferlin-deficient biopsies were similar, though rimmed vacuoles were unique to dysferlinopathy, while inflammatory infiltrates were present in both these limb-girdle muscular dystrophy type 2D biopsies. Macrophages were detected in seven dysferlinopathy biop-sies. The results of this study suggest that the distribution of limb-girdle muscular dystrophy sub-types in the Han Chinese population is similar to that reported in the West. The less necrotic, re-generating and inflammatory appearance of limb-girdle muscular dystrophy type 2A, but with more lobulated fibers, supports the idea that calpainopathy is a less active, but more chronic disease than dysferlinopathy. Unusual features indicated an extended limb-girdle muscular dystrophy disease spectrum. The use of acid phosphatase stain should be considered in suspected dysferlinopathies. To the best of our knowledge, this is the first report to define the relative proportions of the various forms of limb-girdle muscular dystrophy in China, based on protein testing.

关键词： neural regeneration limb-girdle muscular dystrophy calpain 3 α-sarcoglycan dysferlin caveolin-3 grants-supported paper neuroregeneration

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Remodeling dendritic spines for treatment of traumatic brain injury

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Neural Regeneration Research 2019年第9期14卷 1477-1480页

作者： Ye Xiong Asim mahmood Michael Chopp Department of Neurosurgery Henry Ford HospitalDetroitMIUSA Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA

Traumatic brain injury is an important global public health *** brain injury not only causes neural cell death,but also induces dendritic spine *** neurons from cell death in the injured brain may exhibit dendrite damage,dendritic spine degeneration,mature spine loss,synapse loss,and impairment of *** degeneration and synapse loss may significantly contribute to functional impairments and neurological disorders following traumatic brain *** function of the nervous system depends on maintenance of the functionally intact synaptic connections between the presynaptic and postsynaptic spines from neurons and their target *** synaptic plasticity,the numbers and shapes of dendritic spines undergo dynamic *** of spine heads and the formation and stabilization of new spines are associated with long-term potentiation,while spine shrinkage and retraction are associated with long-term *** of memory is associated with remodeling and growth of preexisting synapses and the formation of new *** date,there is no effective treatment to prevent dendritic degeneration and synapse *** review outlines the current data related to treatments targeting dendritic spines that propose to enhance spine remodeling and improve functional recovery after traumatic brain *** mechanisms underlying proposed beneficial effects of therapy targeting dendritic spines remain elusive,possibly including blocking activation of Cofilin induced by beta amyloid,Ras activation,and inhibition of GSK-3 signaling *** understanding of the molecular and cellular mechanisms underlying synaptic degeneration/loss following traumatic brain injury will advance the understanding of the pathophysiology induced by traumatic brain injury and may lead to the development of novel treatments for traumatic brain injury.

关键词： traumatic brain injury dendritic spines synaptic plasticity spinogenic agents treatment spine remodeling memory functional recovery

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Characterization of semisolid deformation behavior of a high Zr-containing WE magnesium alloy

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Rare Metals 2022年第12期41卷 4201-4208页

作者： Masoud Moradjoy-Hamedani Abbas Zarei-Hanzaki Seyed mahmood Fatemi School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 515-14395Iran School of Mechanical Engineering Shahid Rajaee Teacher Training UniversityTehran 136-16785Iran

The effects of temperature and strain rate on the semisolid deformation behavior of a high Zr WE54 magnesium alloys were studied at temperatures of 570,595 and 620℃.A flow stress peak was appeared during deformation of the feedstock experimental material at deformation conditions of 570℃,0.010 and 0.100 s-1,and 595℃,0.100 *** latter results were connected to the occurrence of dynamic recrystallization in solid ***,these conditions were gauged to be able to activate"lubricated flow"*** 570℃and strain rate of 0.001 s-1as well as 595℃and rates of 0.010 and 0.001 s^(-1),the flow stress increases and reaches a plateau,where dynamic recovery is considered as the dominant ***,at 620℃under all the strain rates,the flow stress drops for a limited strain range and then increases *** results show that as the liquid removes from the boundaries between the solid parts,the densification of the globules occurs at higher strains,causing an increase in the flow *** analysis points out that the feedstock material exhibits a lower flow stress than as-cast alloy associating with a modified morphology of Zr particles after deformation.

关键词： Mg-RE alloy Feedstock Semisolid deformation Liquid flow

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Recovery of NH4^＋ by corn cob produced biochars and its potential application as soil conditioner

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 825-834页

作者： Yang ZHANG Zifu LI Ibrahim B mahmood School of Civil & Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

NH4^＋ ion, a main pollutant in aquatic systems, not only causes eutrophication in rivers and lakes but also contributes to fish toxicity. In this study, an eco-friendly biosorbent was prepared from the pyrolysis of corn cob, a low-cost agricultural residue. The biochars produced by pyrolysis of corn cob at 400℃ and 600℃ were characterized and investigated as adsorbents for NH4＋ -N from an aqueous solution. The biochars were characterized through elemental analysis, Brunauer-Emmett-Teller-N2 surface area analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. Batch experiments were conducted to investigate the NH4＋ adsorption process of the corn cob biochars. The Freundlich isotherm model fitted the adsorption process better than the Langmuir and Dubinin-Radushkevich isotherm models. Moreover, the adsorption process was well described by a pseudo-second-order kinetic model. Results of thermodynamic analysis suggested that adsorption was a nonspontaneous exothermic process. Biochars produced at 400℃ had higher adsorption capacity than those produced at 600℃ because of the presence of polar functional groups with higher acidity. The exhausted biochar can be potentially used as soil conditioner, which can provide 6.37 kg NH4＋-N-t^-1 （N fertilizer per ton of biochar）.

关键词： corn cob biochar NH+ adsorption isotherm model kinetic model

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Mesenchymal stem cell-derived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration

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Neural Regeneration Research 2024年第1期19卷 49-54页

Traumatic brain injury is a serious and complex neurological condition that affects millions of people *** significant advancements in the field of medicine,effective treatments for traumatic brain injury remain ***,extracellular vesicles released from mesenchymal stem/stromal cells have emerged as a promising novel therapy for traumatic brain *** vesicles are small membrane-bound vesicles that are naturally released by cells,including those in the brain,and can be engineered to contain therapeutic cargo,such as anti-inflammatory molecules,growth factors,and *** administered intravenously,extra cellular vesicles can cross the blood-brain barrier and deliver their cargos to the site of injury,where they can be taken up by recipient cells and modulate the inflammatory response,promote neuroregeneration,and improve functional *** preclinical studies,extracellular vesicle-based therapies have shown promising results in promoting recove ry after traumatic brain injury,including reducing neuronal damage,improving cognitive function,and enhancing motor *** further research is needed to establish the safety and efficacy of extra cellular vesicle-based therapies in humans,extra cellular vesicles represent a promising novel approach for the treatment of traumatic brain *** this review,we summarize mesenchymal ste m/stromal cell-de rived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration and brainderived extracellular vesicles as potential biofluid biomarkers in small and large animal models of traumatic brain injury.

关键词： biomarkers extracellular vesicles functional outcome mesenchymal stem/stromal cells neuroinflammation neuroplasticity neuroprotection traumatic brain injury

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Reductive amination of aldehydes and ketones using sodium borohydride in the presence of silica chloride under solvent-free conditions

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Chinese Chemical Letters 2010年第1期21卷 47-50页

作者： Heshmatollah Alinezhad mahmood Tajbakhsh Neda Hamidi Faculty of Chemistry Mazandaran UniversityBabolsarIran

A simple and convenient procedure for the preparation of amines from aldehydes and ketones with sodium borohydride activated by silica chloride as a catalyst under solvent-free conditions is described.A variety of aliphatic and aromatic aldehydes,ketones and amines when mixed with NaBH;/silica chloride at room temperature,afforded excellent yield of the corresponding amines.

关键词： Reductive amination Silica chloride Solvent-free conditions Sodium borohydride

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Emerging potential of exosomes for treatment of traumatic brain injury

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Neural Regeneration Research 2017年第1期12卷 19-22页

Traumatic brain injury（TBI） is one of the major causes of death and disability *** effective treatment has been identified from clinical *** evidence exists that treatment with mesenchymal stem cells（MSCs） exerts a substantial therapeutic effect after experimental brain *** addition to their soluble factors,therapeutic effects of MSCs may be attributed to their generation and release of *** are endosomal origin small-membrane nano-sized vesicles generated by almost all cell *** play a pivotal role in intercellular *** delivery of MSC-derived exosomes improves functional recovery and promotes neuroplasticity in rats after *** effects of exosomes derive from the exosome content,especially micro RNAs（mi RNAs）.mi RNAs are small non-coding regulatory RNAs and play an important role in posttranscriptional regulation of *** with their parent cells,exosomes are more stable and can cross the blood-brain *** have reduced the safety risks inherent in administering viable cells such as the risk of occlusion in microvasculature or unregulated growth of transplanted *** a cell-free exosome-based therapy may open up a novel approach to enhancing multifaceted aspects of neuroplasticity and to amplifying neurological recovery,potentially for a variety of neural injuries and neurodegenerative *** review discusses the most recent knowledge of exosome therapies for TBI,their associated challenges and opportunities.

关键词： traumatic brain injury exosomes microRNAs mesenchymal stem cells treatment neuroplasticity cell therapy

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Morphological Evaluation of PLA/Soybean Oil Epoxidized Acrylate Three-Dimensional Scaffold in Bone Tissue Engineering

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Journal of Renewable Materials 2022年第9期10卷 2391-2408页

作者： mahmood Hameed Majeed Nabeel Kadhem Abd Alsaheb Department of Biomedical Engineering Al Nahrain UniversityAl Jadriya BridgeBaghdad64074Iraq

Tissue engineering’s main goal is to regenerate or replace tissues or organs that have been destroyed by disease,injury,or congenital *** engineering now uses artificial supporting structures called scaffolds to restore damaged tissues and *** are utilized to attach the right cells and then grow *** prototyping appears to be the most promising technology due to its high level of precision and *** tissue replacement“scaffolding”is a common theme discussed in this *** fused deposition technique was used to construct our scaffold,and a polymer called polylactic acids and soybean oil resin were used to construct our *** samples were then divided into two groups;the first group was left without immersion in the simulated body fluid and served as a control for *** second group was immersed in the simulated body *** results of the Field Emission Scanning Electron Microscope(FESEM),Energy Dispersive X-ray Spectroscopy(EDX)and X-ray diffraction(XRD)were utilized to interpret the surface attachment to ions,elements,and compounds,giving us a new perspective on scaffold *** this study,an innovative method has been used to print therapeutic scaffold that combines fused deposition three-dimensional printing with ultraviolet curing to create a high-quality biodegradable polymeric ***,the results demonstrate that adding soybean oil resin to the PLA increased ion attachment to the surface while also attracting tricalcium phosphate formation on the surface of the scaffold,which is highly promising in bone tissue *** conclusion,the soybean oil resin,which is new in the field of bone tissue engineering,shows magnificent characteristics and is a good replacement biopolymer that replaces many ceramic and polymeric materials used in this field that have poor morphological characteristics.

关键词： Bone tissue engineering polylactic acid soybean oil biodegradable polymers fused deposition modeling scaffold

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Drainage Network and Lineament Analysis:An Approach for Potwar Plateau(Northern Pakistan)

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Journal of Mountain Science 2009年第1期6卷 14-24页

作者： Faisal SHAHZAD Syed Amer mahmood Richard GLOAGUEN Remote Sensing Group Institute of GeologyFreiberg University of Mining and TechnologyFreiberg09599Germany.

Drainage responds rapidly to tectonic changes and thus it is a potential parameter for teetonogeomorphological analysis. Drainage network of Potwar is a good geological record of movement, displacements, regional uplifts and erosion of the tectonic units. This study focuses on utilizing drainage network extracted from Shuttle Radar Digital Elevation Data （SRTM-DEM） in order to constrain the structure of the Potwar Plateau. SWAN syncline divides Potwar into northern Potwar deformed zone （NPDZ） and southern Potwar platform zone （SPPZ）. We extracted the drainage network from DEM and analyzed 112 streams using stream power law. Spatial distribution of concavity and steepness indices were used to prepare uplift rate map for the area. DEM was further utilized to extract lineaments to study the mutual relationship between lineaments and drainage patterns. We compared the local correlation between the extracted lineaments and drainage network of the area that gives us quantitative information and shows promising prospects. The streams in the NPDZ indicate high steepness values as compared to the streams in the SPPZ. The spatial distribution of geomorphic parameters distinctive deformation and uplift rates suggest the among eastern, central and western parts. The local correlation between drainage network and lineaments from DEM is strongly positive in the area within I km of radius.

关键词： Drainage network lineaments streamprofile analysis uplift rate local correlation

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