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Noninvasive assessment of portal hypertension in cirrhosis:Liver stiffness and beyond

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World Journal of Gastroenterology 2014年第45期20卷 16811-16819页

作者： Horia Stefanescu bogdan Procopet Department of Medical and Surgical Sciences University of Bologna Regional Institute of Gastroenterology and Hepatology Liver Hemodynamic Unit Hospital Clinic 3rd Medical Clinic Iuliu Hatieganu University of Medicine and Pharmacy

Liver stiffness measurement(LSM)is a good,but still limited tool to noninvasively assess complications and prognosis in patients with advanced liver *** review aims to consider the role of LSM for the diagnosis of portal hypertension-related complications and for assessment of prognosis in cirrhotic patients,and to highlight the drawbacks as well as some alternatives for improving the ***,this field is far from being closed,and deserves more *** is still a place for more carefully designed studies to find new,innovative and reliable approaches.

关键词： Liver stiffness Portal hypertension Complication Spleen stiffness Prediction

Energy balance model to assess the resistance of ballistic protection materials

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Defence Technology（防务技术） 2023年第12期30卷 141-153页

作者： bogdan Stirbu Irene Ndindabahizi Tom Vancaeyzeele Cyril Robbe Department of Weapon Systems and Ballistics Royal Military AcademyBrussels 1000Belgium

NATO standards"AEP-2920 Procedures for the Evaluation and Classification of Personal Armor"and NIJ Standard-0101.06,indicate the method to statistically assess the resistance of personal ballistic protection *** be validated and accepted through these procedures,a personal ballistic protection material should withstand an impact of a specific projectile with a probability of a partial penetration confidence level higher than 90%.The present study introduces an energy equilibrium method to assess the confidence level for the probability of partial penetration of ductile and brittle *** experiments performed in the Ballistics laboratory of the Royal Military Academy in Belgium,use a modified pendulum method that allowed the quantification of the energy balance before and after the ballistic *** results were then compared with the ones obtained using the method specified by the NATO standard and NIJ 0101.06,mentioned *** outcome of this comparison shows the tendency of the values obtained by the pendulum method to faithfully follow the values obtained according to NATO and NIJ *** presented method is not based on statistical estimations,but instead,an exact method,of computing the energy absorbed by the tested *** is an advantage for the cases when the material to be evaluated is expensive or it is in the development phase and mass production is not possible.

关键词： Energy NATO Ballistic Protection materials Statistics NIJ Bootstrapping

Diagnosis of cirrhosis and portal hypertension:imaging,non-invasive markers of fibrosis and liver biopsy

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Gastroenterology Report 2017年第2期5卷 79-89,I0001页

作者： bogdan Procopet Annalisa Berzigotti University of Medicine and Pharmacy‘Iuliu Hatieganu’ 3rd Medical Clinic and Hepatology DepartmentRegional Institute of Gastroenterology and Hepatology‘O Fodor’Cluj-NapocaRomania Swiss Liver Center HepatologyUniversity Clinic for Visceral Surgery and MedicineInselspitalUniversity of BernBernSwitzerland

The concept of‘cirrhosis’is evolving and it is now clear that compensated and decompensated cirrhosis are completely different in terms of ***,the term‘advanced chronic liver disease(ACLD)’better reflects the continuum of histological changes occurring in the liver,which continue to progress even after cirrhosis has developed,and might regress after removing the etiological factor causing the liver *** compensated ACLD,portal hypertension marks the progression to a stage with higher risk of clinical complication and requires an appropriate evaluation and *** tests to diagnose cirrhosis(liver biopsy)and portal hypertension(hepatic venous pressure gradient measurement and endoscopy)remain of crucial importance in several difficult clinical scenarios,but their need can be reduced by using different non-invasive tests in standard *** non-invasive tests,the accepted use,major limitations and major benefits of serum markers of fibrosis,elastography and imaging methods are summarized in the present review.

关键词： compensated advanced chronic liver disease hepatic venous pressure gradient elastography ultrasound

Forward Scattering Series and Pade Approximants for Acoustic Wavefield Propagation in a Vertically Varying Medium

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Communications in Computational Physics 2008年第1期3卷 180-202页

作者： bogdan G.Nita Department of Mathematical Sciences Montclair State University1 Normal AvenueMontclairNJ 07043USA.

We present the application of the theory of Pade approximants to extending the perturbative solutions of acoustic wave equation for a three dimensional vertically varying medium with one *** type of solutions have limited convergence properties depending on either the degree of contrast between the actual and the reference medium or the angle of incidence of a plane wave *** show that the sequence of Pade approximants to the partial sums in the forward scattering series for the 3D wave equation is convergent for any contrast and any incidence *** allows the construction of any reflected waves including phase-shifted post-critical plane waves and,for a point-source problem,refracted events or headwaves,and it also provides interesting interpretations of these solutions in the scattering theory formalism.

关键词： Acoustic wave modeling forward scattering series Pade approximants

Comparison of stem volume estimates from terrestrial point clouds for mature Douglas-fir(Pseudotsuga menziessi(Mirb.)Franco)

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Information Processing in Agriculture 2023年第3期10卷 334-346页

作者： Rong Fang bogdan M.Strimbu Forest Engineering Resourcesand Management DepartmentOregon State UniversityCorvallisOR 97333 ORUSA

As a complement to traditional estimates of stem dimensions from numerical models,terrestrial light detection and ranging(Lidar)provides direct stem diameter and volume values using cylindrical models constructed from point *** study used two approaches to estimate total stem volume using Lidar and compared them with two empirical equations,one used by the Forest Inventory Analysis in the Pacific Northwest(FIA-PNW)and one based on a taper *** fitted point clouds of 10 Douglas-fir with three sets of cylinder models that are distinguished by their segment length(i.e.0.5 m,1 m,and 2 m),then developed three taper equations based on the point-cloud-based diameter estimated *** estimated the total stem volume of the tree with eight models:six-point cloudbased(*** taper and three cylinders)and two ***,we used simulations to extrapolate the volume estimations of various methods for different diameters at breast height(DBH)*** found that all the point-cloud-based taper equations were similar in their performance(R2¼0:94,RMSE=4.6 cm)and produced mean volume estimates greater than mean estimates of the existing *** cylinder models produced 11–16%greater mean volume estimates than the FIA-PNW estimate,with the 0.5 m segment length producing the greatest values,followed by the 1 m and 2 m segment *** simulated data suggested that the mean volume estimates of a given DBH class are different when using different computation *** revealed a combined effect of the computation methods and the DBH class on the mean volume *** conclude that the point-cloud-based taper equations,after being symmetrically calibrated,would be consistent with the regional stem volume estimates,whereas the cylinder models would be better in estimating individual stem *** constructing Lidar-based cylinder models in future applications,cylinder segment length would need to be adjusted to the length and DBH of the stem

关键词： Lidar Cylinder models Cylinder segment length Taper equations Forest inventory and analysis

Improvement of PCR reaction conditions for site-directed mutagenesis of big plasmids

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第4期13卷 244-247页

作者： bogdan MUNTEANU Mario BRAUN Kajohn BOONROD RLP AgroScience GmbH AlPlanta-Institute for Plant ResearchBreitenweg 71D-67435 NeustadtGermany

QuickChange mutagenesis is the method of choice for site-directed mutagenesis （SDM） of target sequences in a plasmid. It can be applied successfully to small plasmids （up to 10 kb）. However, this method cannot efficiently mutate bigger plasmids. Using KOD Hot Start polymerase in combination with high performance liquid chromatography （HPLC） purified primers, we were able to achieve SDM in big plasmids （up to 16 kb） involving not only a single base change but also multiple base changes. Moreover, only six polymerase chain reaction （PCR） cycles and 0.5μI of polymerase （instead of 18 PCR cycles and 1.0 μI of enzyme in the standard protocol） were sufficient for the reaction.

关键词： Site-directed mutagenesis (SDM) Mutant Plasmid

Axon degeneration： make the Schwann cell great again

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Neural Regeneration Research 2017年第4期12卷 518-524页

作者： Keit Men Wong Elisabetta Babetto bogdan Beirowski Hunter James Kelly Research Institute Jacobs School of Medicine and Biomedical Sciences University at Buffalo Buffalo NY USA Department of Pharmacology and Toxicology Jacobs School of Medicine and Biomedical Sciences University at Buffalo Buffalo NY USA Department of Biochemistry Jacobs School of Medicine and Biomedical Sciences University at Buffalo Buffalo NY USA

Axonal degeneration is a pivotal feature of many neurodegenerative conditions and substantially accounts for neurological morbidity. A widely used experimental model to study the mechanisms of axonal degeneration is Wallerian degeneration （WD）, which occurs after acute axonal injury. In the peripheral nervous system （PNS）, WD is characterized by swift dismantling and clearance of injured axons with their myelin sheaths. This is a prerequisite for successful axonal regeneration. In the central nervous system （CNS）, WD is much slower, which significantly contributes to failed axonal regeneration. Although it is well documented that Schwann cells （SCs） have a critical role in the regenerative potential of the PNS, to date we have only scarce knowledge as to how SCs ＇sense＇ axonal injury and immediately respond to it. In this regard, it remains unknown as to whether SCs play the role of a passive bystander or an active director during the execution of the highly orchestrated disintegration program of axons. Older reports, together with more recent studies, suggest that SCs mount dynamic injury responses minutes after axonal injury, long before axonal breakdown occurs. The swift SC response to axonal injury could play either a pro degenerative role, or alternatively a supportive role, to the integrity of distressed axons that have not yet committed to degenerate. Indeed, supporting the latter concept, recent 昀ndings in a chronic PNS neurodegeneration model indicate that deactivation of a key molecule promoting SC injury responses exacerbates axonal loss. If this holds true in a broader spectrum of conditions, it may provide the grounds for the development of new glia-centric therapeutic approaches to counteract axonal loss.

关键词： Wallerian degeneration neurodegeneration glia oligodendrocytes myelin dedifferentiation

Clear cell colitis: A form of microscopic colitis in children

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World Journal of Gastroenterology 2008年第2期14卷 231-235页

作者： Jan Józefczuk bogdan Marian Wozniewicz Pediatric Division City Hospital 39-360 Nowa Deba M. Curie Sklodowska 1 Poland Department of Pathology The Children’s Memorial Health Institute Aleja Dzieci Polskich 20 Warsaw 04-730 Poland

AIM: To describe a new clinical and pathological subtype of microscopic colitis in children. METHODS: A selected group of children with abdominal pain, constipation and/or diarrhoea showing discrete or no macroscopic abnormalities on endoscopy was described. RESULTS: Multiple biopsies of colon showed large mononuclear clear cells in lamina propria of mucous membrane provided that good quality histological sections were performed and observed under a higher magnification. Otherwise, they could be misinterpreted as artefacts. Their presence in routine histology might suggest a systemic storage disease (Whipple’s disease), and neuronal intestine dysplasia. Using immunohistochemical staining and electron microscopy we confirmed their origin from CD68 positive mononuclear macrophages. CONCLUSION: The presence of large clear cells is a constant microscopic feature. Failure of transient large bowel stationary macrophages plays a role in the pathogenesis of this benign microscopic clear cell colitis, sometimes coexisting with allergy.

关键词： Microscopic colitis Clear cell colitis Diarrhoea Constipation Abdominal pain Children Allergy Endoscopy

Geographic information system (GIS) application for windthrow mapping and management in Iezer Mountains, Southern Carpathians

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Journal of Forestry Research 2012年第2期23卷 175-184页

作者： Savulescu Ionut Mihai bogdan Department of Geomorphology-Pedology and Geomatics Faculty of GeographyUniversity of Bucharest1Nicolae Balcescu Blvd.010041 BucharestSector 1Romania

Windthrow problem is a difficult task for the forest managers in the Romanian Carpathians and especially in Iezer Mountains. The last windthrow, in July 2005, affected about 370 ha within the study area and left unprotected large slopes with important declivities （20-30°）. In our study, we try to propose a tool for forest management, in order to control and minimize the negative effect of wind upon the mountain forest ecosystem. The digital data input derived from forestry data （forest stand typology, age, canopy coverage index, forest productivity class） and from the forest biotope features （soil and topography parameters）. The main goal was to find a more objective way for digital layer reclassification in order to obtain the windthrow areas susceptibility map for the Iezer Mountains. Each digital layer has its own weight within the analysis and one of them was difficult to be modeled （the wind features）. A statistical approach was developed on the basis of local phenomena and the wind- throw features in the Romanian Carpathians. This allowed us to obtain the reclassification conditions for each digital layer. Forest canopy typology and soil features （mainly its volume） were considered as the key factors for the windthrow occurrence analysis. The final windthrow susceptibility map was validated with the help of the statistic occurrence of windthrow areas within each susceptibility class and after a field check of the sites. The result was encouraging, because 92.5% of the windthrow areas fall into the highest windthrow susceptibility class.

关键词： windthrow GIS forest map susceptibility