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An oxygenating colloidal bioink for the engineering of biomimetic tissue constructs

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Bio-Design and Manufacturing 2024年第3期7卷 240-261页

作者： Seol-Ha Jeong Jarno Hiemstra Patrick V.Blokzijl Rebeca damian-Ferrara Danilo Martins dos Santos Jéssica H.L.da Fonseca Min-Ho Kang Jihyun Kim Dilara Yilmaz-Aykut Mei L.L.Cham-Pérez Jeroen Leijten Su Ryon Shin Division of engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolBostonMA 02139USA Leijten Lab Department of Developmental BioEngineeringFaculty of Science and TechnologyTechnical Medical CentreUniversity of TwenteDrienerlolaan 57522 NB EnschedeThe Netherlands Nanotechnology National Laboratory for Agriculture(LNNA) Embrapa InstrumentaçãoSao CarlosSao Paulo 13560-970Brazil Department of Biomedical-Chemical engineering The Catholic University of Korea43 Jibong-roBucheon-siGyeonggi-do 14662Republic of Korea Department of Biotechnology The Catholic University of Korea43 Jibong-roBucheon-siGyeonggi-do 14662Republic of Korea

ensuring a sufficient oxygen supply is pivotal for the success of bioprinting applications since it fosters tissue integration and natural *** in oxygen concentration among diverse tissues necessitates the precise recreation of tissue-specific oxygen levels in imprinted constructs to support the survival of targeted *** oxygen-releasing biomaterials,such as oxygen-generating microparticles(OMPs),have shown promise for enhancing the oxygen supply of microenvironments in injured tissues,whether this approach is scalable for large tissues and whether tissue-specific bioinks with varying OMP concentrations remain printable remain *** study addresses this critical gap by introducing an innovative class of engineered oxygenated bioinks that combine colloidal-based microgels with *** report that incorporating nanosized calcium peroxide(nCaO_(2))and manganese oxide nanosheets(nMnO_(2))into hydrophobic polymeric microparticles enables precise modulation of oxygen release while controlling hydrogen peroxide ***,the fabrication of oxygenating and cytocompatible colloidal gels is achieved using an aqueous two-phase *** study thoroughly evaluates the fundamental characteristics of the resulting bioink,including its rheological behaviors,printability,shape fidelity,mechanical properties,and oxygen release ***,this study demonstrates the macroscopic scalability and cytocompatibility of printed constructs produced via cell-laden oxygenating colloidal *** showcasing the effectiveness of extrusion-based bioprinting,this study underscores how it can be used to fabricate biomimetic tissues,indicating its potential for new *** findings presented here advance the bioprinting field by achieving scalability with both high cell viability and the possibility of mimicking specifically oxygenated *** work thereby offers a promising avenue for the development of functional tissues with e

关键词： 3D bioprinting Bioink Colloidal gels extrusion printing Oxygen-generating microparticle

Can active late-type stars contribute to the Galactic lithium abundance?

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Research in Astronomy and Astrophysics 2020年第7期20卷 127-133页

作者： Darnell e.Kelly damian J.Christian Mihalis Mathioudakis Darko Jevremovi′c Department of Physics and Astronomy California State UniversityNorthridgeCA 91330-8268USA Astrophysics Research Centre School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUK Astronomical Observatory Volgina 711060 BelgradeSerbia

Lithium abundances in our Galaxy and especially 6 Li abundances provide important constraints on our understanding of Big Bang Nucleosynthesis(BBNS),stellar evolution and the creation of light elements by cosmic rays in the ISM.~6 Li has been detected in energetic solar events,one chromospherically active binary and several dwarf halo *** our work on active late-type stars with high lithium abundances,we expand our study to consider if the flare origin of lithium created by spallation can contribute significantly to the Galactic abundance of *** previously derived ~6 Li/~7 Li=0.030 ± 0.010 for active K dwarf GJ 117 using VLT UVeS *** find^6 Li/~7 Li ratios of 0.02 and 0.10 for two other stars in our sample,GJ 182 and eUVe J1145-55.3 A,*** that these later type,active stars have significant flare rates and stellar winds,we have estimated the contribution of these stars to the Galactic lithium *** that K and M stars comprise over 84% of our Galaxy and that many of these can have significant stellar winds,we conclude that spallation in stellar flares can contribute 1% and up to 5% of the Galactic lithium abundance.

关键词： stars:abundances stars:activity Galaxy:abundances

Using a fluvial archive to place extreme flood sediment(dis)connectivity dynamics in context of a longer-term record

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International Journal of Sediment Research 2022年第4期37卷 447-456页

作者： Kirstie Fryirs Chris Thompson damian Gore School of Natural Sciences Macquarie University Seqwater

The aim of this study was to establish the source and provenance of sediments deposited in a large floodplain sink during extreme floods in the Lockyer Creek catchment, Australia, in 2011 and 2013. We place the sediment source patterns in context of the longer-term record to determine whether coarsegrained sediment sources(i.e., very fine sand to very coarse sand) and the spatio-temporal pattern of(dis)connectivity have changed over time. We do this by matching the geochemical properties and age structure of a sediment profile located in a downstream floodplain sink to the elemental composition of source sediments. One hundred and fifty-seven sediment samples from 20 sites across the catchment are analysed using X-ray fluorescence(XRF) spectrometry to compare the elemental ratio composition of the downstream floodplain sink to its source materials. We use Optically Stimulated Luminescence(OSL)dating to determine the age structure of the sediments in the floodplain sink. The northern tributaries and parts of the Lockyer River trunk stream are the primary sources of coarse sediment. These areas are connected(coupled) to the lower trunk stream and floodplain sediment sink. Southern tributaries are largely disconnected(decoupled) and supply little sediment to the floodplain sediment sink. This pattern of sediment source contribution has remained similar over the last 6.8 ka at least. Sediment sources as observed in the 2011 flood have predominated over the mid-late Holocene whilst those in the 2013 flood are rare.

关键词： Sediment provenance Geomorphology Sediment source Sediment sink Lockyer Valley

Origins of the supercontinent cycle

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Geoscience Frontiers 2013年第4期4卷 439-448页

作者： R.damian Nance J.Brendan Murphy Department of Geological Sciences.316 Clippinger Laboratories.Ohio University.Athens.OH 45701.USA Department of earth Sciences st.Francis Xavier UniversityAntigonishNova Scotia B2G 2W5.Canada

The supercontinent cycle, by which earth history is seen as having been punctuated by the episodic assembly and breakup of supercontinents, has influenced the rock record more than any other geologic phenomena, and its recognition is arguably the most important advance in earth Science since plate tectonics. It documents fundamental aspects of the planet＇s interior dynamics and has charted the course of earth＇s tectonic, climatic and biogeochemical evolution for billions of years. But while the widespread realization of the importance of supercontinents in earth history is a relatively recent development, the supercontinent cycle was first proposed thirty years ago and episodicity in tectonic processes was recognized long before plate tectonics provided a potential explanation for its occurrence. With interest in the supercontinent cycle gaining momentum and the literature expanding rapidly, it is instructive to recall the historical context from which the concept developed. Here we examine the supercontinent cycle from this perspective by tracing its development from the early recognition of long-term epi- sodicity in tectonic processes, through the identification of tectonic cycles following the advent of plate tectonics, to the first realization that these phenomena were the manifestation of episodic superconti- nent assembly and breakup.

关键词： Supercontinent cyclePlate tectonicsTectonic episodicitySecular trends

Random checkerboard based homogenization for estimating effective thermal conductivity of fully saturated soils

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Journal of Rock Mechanics and Geotechnical engineering 2017年第1期9卷 18-28页

作者： Dariusz Lydzba Adrian Rózanski Magdalena Rajczakowska damian Stefaniuk Department of Geotechnics HydrotechnicsUnderground and Hydraulic StructuresFaculty of Civil EngineeringWroclaw University of Science and TechnologyWybrzeze Wyspianskiego 27Wrocw50-370Poland

This paper proposes homogenization scheme for estimating the effective thermal conductivity of fully saturated soils. This approach is based on the random checkerboard-like microstructure. Two modeling scales and two modeling approaches are distinguished and used, i.e. microscale and mesoscale and 1-step and 2-step homogenizations, respectively. The 2-step homogenization involves sequential averaging procedure, i.e. first, at microscale, a mineralogical composition of soil skeleton is considered and averaging process results in estimation of the skeleton effective thermal conductivity, and then, at mesoscale, a random spatial packing of solid skeleton and pores via random checkerboard microstructure is modeled and leads to evaluation of the soil overall thermal conductivity. The 1-step homogenization starts directly at the mesoscale and homogenization procedure yields evaluation of the overall soil thermal conductivity. At the mesoscale, the distinct nature of soil skeleton, as composed of soil separates,is considered and random variability of soil is modeled via enriched random checkerboard-like *** approaches, i.e. 1-step and 2-step homogenizations, interrelate mineralogical composition with the soil texture characterized by the volume fractions of soil separates, i.e. sand, silt and clay. The probability density functions(PDFs) of thermal conductivity are assumed for each of the separates. The soil texture PDF of thermal conductivity is derived taking into consideration the aforementioned functions. Whenever the random checkerboard-like structure is used in averaging process, the Monte Carlo procedure is applied for estimation of homogenized thermal conductivity. Finally, the proposed methodology is tested against the laboratory data from our measurements as well as those available from literature.

关键词： Soil mechanics Micromechanics effective thermal conductivity

Spring recharge and groundwater flow patterns in flysch aquifer in the Polonina Wetlińska Massif in the Carpathian Mountains

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Journal of Mountain Science 2021年第4期18卷 819-833页

作者： Karolina MOSTOWIK damian KRZYCZMAN eliza PLACZKOWSKA Bartlomiej RZONCA Janusz SIWeK Patryk WACLAWCZYK Institute of Geography and Spatial Management Jagiellonian University in KrakowGronostajowa St.730-387 KrakowPoland Institute of Geography and Spatial Organization Polish Academy of SciencesSw.Jana St.2231-018 KrakowPoland

Flysch-type aquifers in the eastern Carpathians usually feed periodic and low-discharge springs. However, in some areas, such as in the upper part of the Polonina Wetlińska Massif, perennial springs with a relatively high discharge were identified. Therefore, the aim of this study was to identify recharge and groundwater flow patterns of three high-discharge springs based on the response of spring discharge to rainfall and on the relationship between specific electrical conductivity of water and spring discharge. The relation between spring discharge and rainfall was investigated by crosscorrelation analyses. Generally, cumulative rainfall over a period from 10 days to 3 months is most strongly correlated with discharge;however, the response time of spring discharge varies throughout the year. Faster response to rainfall occurs in the spring after snowmelt, while in the summer and autumn months the response time increases. Two flow systems were identified: 1) a relatively deep, fissure-pore flow system with a long response time to precipitation and 2) a shallow, fissure-dominated system with a short response time, which is superimposed on the longer response. A small range of specific electrical conductivity combined with the varying discharge of two springs suggests that dilution of groundwater by rainwater does not play a significant role. The differences in the studied springs’ response to rainfall can be attributed to the recharge area, regolith features and local bedrock structures, i.e. occurrence of joints and faults, monoclinal dip of rock layers and gravitational slope deformations including ridge-top trenches, which, thus far, have been underestimated in determining groundwater storage capacity in the flysch part of the Carpathians.

关键词： Cross-correlation Rainfall recharge Spring response Sedimentary rocks Poland

Prevalence and Determinants of Modern Contraceptive Methods Use among Women of Reproductive Age (15 - 49 Years) in Rural Setting: A Case of Kishapu District, Shinyanga Region

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Advances in Sexual Medicine 2019年第4期9卷 53-66页

作者： Veronica Martin Sia e. Msuya Ntuli Kapologwe damian J. damian Beatrice John Michael J. Mahande Department of epidemiology and Biostatistics Institute of Public Health Kilimanjaro Christian Medical University College Moshi Tanzania Kilimanjaro Christian Medical Centre Moshi Tanzania Community Health Department Kilimanjaro Christian Medical University College Moshi Tanzania Shinyanga Regional Medical Office Shinyanga Tanzania

Background: Modern contraceptive use among women of reproductive age (15 - 49 years) is a public health priority in Tanzania. The national prevalence remains unacceptably low as 32%. Shinyanga region is one among the regions with lowest contraceptive prevalence rate (21%) and high unmet need for family planning (23%). Understanding factors contributing to its use may help to improve maternal and child health. This study aimed to assess the prevalence and determinants of modern contraceptive use among women of reproductive age. Methods: A community-based cross-sectional study was conducted in Kishapu district of Shinyanga region: A total of 602 women aged 15 - 49 years were interviewed using a standardized questionnaire. Data were analysed using SPSS version 20.0. Odds ratios with 95% confidence intervals for factors associated with use of modern contraceptives were estimated in multivariable logistic regression models. Results: The prevalence of modern contraceptive use was 42.7%. Being employed (OR 2.42, 95% CI: 1.13 - 5.18), formal educational level (OR 2.45, 95% CI: 1.38 - 4.35), couples communication (OR 2.44, 95% CI: 1.74 - 3.42) and availability of modern contraceptives (OR 1.94, 95% CI: 1.17 - 3.20) were significantly associated with current use of modern contraceptives. Husband disapproval was frequently reported as barrier for modern contraceptives in the study area. Conclusions: Numerous factors were associated with use of modern contraceptives. Husband disapproval was frequently reported as barrier for contraceptive use. Strategies to promote the importance of modern contraceptives use in the study area are warranted. District health office and concerned stakeholders should encourage male involvement for family planning.

关键词： Family Planning Modern Contraceptive Use Prevalence Determinants

Seasonal variation for the antidiabetic activity of Loranthus micranthus methanol extract

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Asian Pacific Journal of Tropical Medicine 2010年第3期3卷 196-199页

作者： Patience Ogoamaka Osadebe edwin Ogechukwu Omeje Philip Felix Uzor ernest Kenechukwu David damian Chiedozie Obiorah Department of Pharmaceutical and Medicinal Chemistry Faculty of Pharmaceutical SciencesUniversity of Nigeria

Objective:To determine the season in which the eastern Nigeria mistletoe,Loranthus micranthus,parasitic on Persea americana possesses optimum antidiabetic activity and to determine the seasonal variation in the ***:The antidiabetic activities of the aqueous methanol extracts of the leaves of eastern Nigeria mistletoe,Loranthus micranthus, harvested in two seasons of the year,the onset of rainy season(April) and the peak of rainy season(July) were *** tests were carried out on six(6) groups(A-F) of alloxaninduced diabetic *** A and B received 200 mg/kg and 400 mg/kg of the April sample extracts respectively while groups C and D received same doses of the July sample extracts. Group e and F which were the positive and negative controls received 10 mg/kg of glibenclamide and 2 ml/kg of 3%tween 20 *** blood glucose levels of the animals were monitored hourly with a glucometer for six *** phytochemical analysis of the plant extracts were also carried out by standard ***:The results showed that group A and B exhibited significant(Percentage reduction in the fasting blood sugar(FBS) level of the animals(38.9%and 39.2%respectively) with maximum reduction observed at the 5th and 6th hour respectively compared to glibenclamide(71.3%).Group C showed no significant (P>0.05) FBS reduction(15.9%) while group D exhibited highly significant(Peduction (47.5%) with the maximum reduction occurring after 6 *** phytochemical analysis of the crude methanol extracts revealed the presence of carbohydrates,glycosides,saponins, tannins,flavonoids,steroids,terpenoids,acidic compounds,resins and *** were present in different proportions in both ***:This study shows that there is a seasonal, dose-dependent variation in the chemical composition viz-a-viz the antidiabetic activity of the plant under *** activity is highest at the peak of the rainy season.

关键词： Antidiabetic activity Loranthus micranthus Methanol extract Phytochemical analysis Seasonal variation

Available for millions of years but discovered through the last decade:Insects as a source of nutrients and energy in animal diets

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Animal Nutrition 2022年第4期11卷 60-79页

作者： Bartosz Kieronczyk Mateusz Rawski Zuzanna Mikołajczak Natalia Homska Jan Jankowski Katarzyna Ognik Agata Jozefiak Jan Mazurkiewicz damian Jozefiak Department of Animal Nutrition Poznan University of Life SciencesPoznanPoland Laboratory of Inland Fisheries and Aquaculture Department of ZoologyPoznan University of Life SciencesPoznanPoland Department of Poultry Science University of Warmia and MazuryOlsztynPoland Department of Biochemistry and Toxicology Faculty of Animal Sciences and BioeconomyUniversity of Life Sciences in LublinLublinPoland Department of Preclinical Sciences and Infectious Diseases Poznan University of Life SciencesPoznanPoland

The aim of this review is to present and discuss the most recent literature about the processing of insect biomass and its impact on nutritive value,further implementation of meals and fats derived from invertebrates to livestock(poultry and swine),aquaculture(salmonids),and companion animal diets and their impact on growth performance,metabolic response,and gastrointestinal microbiota ***,the most important barriers to obtaining unified products in terms of their nutritive value are considered,i.e.,to define insects'nutrient requirements,including various technological groups and further biomass processing(slaughtering,drying,and storage).Due to the current limitation in the insect production process consisting of the lack of infrastructure,there is stress on the relatively small amount of insect products added to the animal diets as a functional feed ***,only in the case of pet nutrition may insects be considered a full replacement for commonly used environmentally harmful and allergenic ***,the least information has been published on this ***,more scientific data are needed,particularly when the pet food branch and insect-based diets are rapidly growing.

关键词： Insect protein Poultry Pig Fish Pet Nutritive value