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2022 ◽  
Vol 4 (1) ◽  
Author(s):  
Hanxiao Chen ◽  
Luqi Xue ◽  
Guidong Gong ◽  
Jiezhou Pan ◽  
Xiaoling Wang ◽  
...  

AbstractCollagen, the main component of mammal skin, has been traditionally used in leather manufacturing for thousands of years due to its diverse physicochemical properties. Collagen is the most abundant protein in mammals and the main component of the extracellular matrix (ECM). The properties of collagen also make it an ideal building block for the engineering of materials for a range of biomedical applications. Reproductive medicine, especially human fertility preservation strategies and reproductive organ regeneration, has attracted significant attention in recent years as it is key in resolving the growing social concern over aging populations worldwide. Collagen-based biomaterials such as collagen hydrogels, decellularized ECM (dECM), and bioengineering techniques including collagen-based 3D bioprinting have facilitated the engineering of reproductive tissues. This review summarizes the recent progress in applying collagen-based biomaterials in reproductive. Furthermore, we discuss the prospects of collagen-based materials for engineering artificial reproductive tissues, hormone replacement therapy, and reproductive organ reconstruction, aiming to inspire new thoughts and advancements in engineered reproductive tissues research. Graphical abstract


2022 ◽  
Vol 8 (1) ◽  
pp. 43-49
Author(s):  
N. Alikhanova ◽  
E. Novruzov

Zosima absinthifolia is the only species of Zosima genus in Azerbaijan. The aim of this study was to determine the quantitative and qualitative determination of fatty acids in the fruits of the plant Zosima absinthifolia, which is widespread in Absheron, as well as to study its physicochemical and organoleptic properties, possible use in the pharmaceutical and food industries. The oil obtained from the fruits of the plant collected from the Absheron Peninsula (Bibiheybat) was analyzed by gas chromatography. The oil was obtained at 60 °C for 8 h by the extraction of the fruits in a Soxhlet extractor. The yield was 10.36%. Chromatographic analysis of the oil obtained from plant fruits allowed to determine 14 fatty acids. The main component of Z. absinthifolia fruit oil is oleic acid (74.36%). Small amounts of caprylic and palmitic acids were also found to be 8.9% and 5.39%, respectively. The lowest percentage is palmitinoleic acid (0.07%). Physico-chemical constants and organoleptic properties of Z. absinthifolia fruit oil were also analyzed and it was determined that the percentage of free fatty acids in our sample was 2.47%, the peroxide value 34.16 mg O/kg and the saponification number 200.23 mg KOH/g.


2022 ◽  
Author(s):  
Raul Abreu de Assis ◽  
Mazilio Coronel Malavazi ◽  
Rubens Pazim ◽  
Gustavo Cannale ◽  
Moiseis Cecconello ◽  
...  

Abstract In the analysis of anthropogenic impact on the environment arises the question of whether the shapes of preserved habitat fragments play an important role in the conservation of wild species. In this work we use a very simple mathematical model based on a reaction-diffusion equation to analyze the effects of geometric shape and area on the permanence of populations in habitat fragments. Our results indicate that a dimensionless quantity calculated from a combination of biological variables is the main component that determines if the species survives in the preserved fragment and whether its geometric shape is important. We provide a methodology to calculate critical area sizes for which population size is most affected by fragment shape. The calculation is based on four quantitative variables: maximum per capita reproduction rate, per capita mortality rate outside the fragment, carrying capacity in the conserved environment and mobility in the disturbed environment. The methodology is illustrated by a preliminary study, in which the model is used to estimate threshold area sizes for habitat fragments for the threatened species Sapajus xanthosternos .


Sensors ◽  
2022 ◽  
Vol 22 (2) ◽  
pp. 567
Author(s):  
Muhammad Husnain ◽  
Khizar Hayat ◽  
Enrico Cambiaso ◽  
Ubaid U. Fayyaz ◽  
Maurizio Mongelli ◽  
...  

The advancement in the domain of IoT accelerated the development of new communication technologies such as the Message Queuing Telemetry Transport (MQTT) protocol. Although MQTT servers/brokers are considered the main component of all MQTT-based IoT applications, their openness makes them vulnerable to potential cyber-attacks such as DoS, DDoS, or buffer overflow. As a result of this, an efficient intrusion detection system for MQTT-based applications is still a missing piece of the IoT security context. Unfortunately, existing IDSs do not provide IoT communication protocol support such as MQTT or CoAP to validate crafted or malformed packets for protecting the protocol implementation vulnerabilities of IoT devices. In this paper, we have designed and developed an MQTT parsing engine that can be integrated with network-based IDS as an initial layer for extensive checking against IoT protocol vulnerabilities and improper usage through a rigorous validation of packet fields during the packet-parsing stage. In addition, we evaluate the performance of the proposed solution across different reported vulnerabilities. The experimental results demonstrate the effectiveness of the proposed solution for detecting and preventing the exploitation of vulnerabilities on IoT protocols.


Author(s):  
Berkiye Sonustun ◽  
Firat M Altay ◽  
Catherine Strand ◽  
Geshanthi Hondhamuni ◽  
Thomas T Warner ◽  
...  

Aggregated alpha-synuclein (-synuclein) is the main component of Lewy bodies (LBs), Lewy neurites (LNs), and glial cytoplasmic inclusions (GCIs), which are pathological hallmarks of idiopathic Parkinson’s disease (IPD) and multiple system atrophy (MSA), respectively. Initiating factors that culminate in forming LBs/LNs/GCIs remain elusive. Several species of -synuclein exist, including phosphorylated and nitrated forms. It is unclear which -synuclein post-translational modifications (PTMs) appear within aggregates throughout disease pathology. Herein we aimed to establish the predominant synuclein PTMs in post-mortem IPD and MSA pathology using immunohistochemistry. We examined the patterns of three -synuclein PTMs (pS87, pS129, nY39) simultaneously in pathology-affected regions of 15 PD, 5 MSA, 6 neurologically normal controls. All antibodies recognized LBs, LNs, and GCIs, albeit to a variable extent. pS129 -synuclein antibody was particularly immunopositive for LNs and synaptic dot-like structures followed by nY39 -synuclein antibody. GCIs, neuronal inclusions, and small threads were positive for nY39 -synuclein in MSA. Quantification of the LB scores revealed that pS129 -synuclein was the dominant and earliest -synuclein PTM followed by nY39 -synuclein, while lower amounts of pSer87 -synuclein appeared later in disease progression in PD. These results may have implications for novel biomarker and therapeutic developments.


2022 ◽  
Author(s):  
Berkiye Sonustun ◽  
Firat M Altay ◽  
Catherine Strand ◽  
Geshanthi Hondhamuni ◽  
Thomas T Warner ◽  
...  

Aggregated alpha-synuclein (α-synuclein) is the main component of Lewy bodies (LBs), Lewy neurites (LNs), and glial cytoplasmic inclusions (GCIs), which are pathological hallmarks of idiopathic Parkinson′s disease (IPD) and multiple system atrophy (MSA), respectively. Initiating factors that culminate in forming LBs/LNs/GCIs remain elusive. Several species of α-synuclein exist, including phosphorylated and nitrated forms. It is unclear which α-synuclein post-translational modifications (PTMs) appear within aggregates throughout disease pathology. Herein we aimed to establish the predominant α-synuclein PTMs in post-mortem IPD and MSA pathology using immunohistochemistry. We examined the patterns of three α-synuclein PTMs (pS87, pS129, nY39) simultaneously in pathology-affected regions of 15 PD, 5 MSA, 6 neurologically normal controls. All antibodies recognized LBs, LNs, and GCIs, albeit to a variable extent. pS129 α-synuclein antibody was particularly immunopositive for LNs and synaptic dot-like structures followed by nY39 -synuclein antibody. GCIs, neuronal inclusions, and small threads were positive for nY39 α-synuclein in MSA. Quantification of the LB scores revealed that pS129 α-synuclein was the dominant and earliest α-synuclein PTM followed by nY39 α-synuclein, while lower amounts of pSer87 α-synuclein appeared later in disease progression in PD. These results may have implications for novel biomarker and therapeutic developments.


Author(s):  
A. V. Kobelev ◽  
S. V. Klement'ev ◽  
A. S. Sirotkin

We examine the agglutinating ability of five compounds, namely, A1, A2, A3, A4 and BS1, isolated from activated sludge on selective media typical of a number of dominant microbial cultures that contribute to the formation of microbial aggregates. The morphological properties of the isolates and their lectin activity, as well as the physiological and biochemical properties of individual isolates were studied; microorganisms in their composition were identified. We assessed the capacity of the isolates under study to synthesize an exopolysaccharide matrix, as well as the sedimentation of activated sludge under the action of the native solution and culture liquid of the BS1 isolate. Based on their capacity to agglutinate, the BS1 and A2 isolates were selected for further research as producers of extracellular lectins and objects of agglutination, respectively. The biophysiochemical properties and molecular-genetic identification of the BS1 isolate allowed the degree of identity with r. Bacillus to be defined (96.19%); for the A2 isolate, 92.93% identity with p. Shigella and p. Escherichia was determined. To assess the capacity to synthesize a biofilm matrix, the BS1 and A2 isolates were cultivated on an agar nutrient solution using Congo Red dye. According to the obtained results, the isolates are capable of synthesizing an exopolysaccharide matrix, the main component of bacterial biofilms. The research results on the sedimentation of activated sludge induced by the native solution and culture liquid of BS1 showed the following. The sedimentation rate of activated sludge increased significantly at the beginning of the process upon adding a BS1 cell suspension, while the introduction of the native solution of BS1 intensified the process following 5 minutes of contact. The obtained experimental data suggest that the media containing extracellular bacterial lectins can be effectively used as a coagulant (flocculant) for the sedimentation of activated sludge.


2022 ◽  
Author(s):  
Fatima Tahir ◽  
Mubo Sonibare ◽  
Sakina Yagi

<i>Nigella sativa</i> L. seeds are widely used in Sudan as a spice, food preservative, and medicine. Sudan does not grow the plant. The study aimed to compare the chemical profile and antibacterial activity of fixed and essential oils of <i>N. sativa</i> from Ethiopian and Indian seeds and the oil offered by Attarin in the local market. A Soxhlet device extracted fixed oils and hydrodistillation to obtain essential oils and analysed their oil profile using GC-MS. Disk diffusion was used to test antimicrobial activity. The fixed oil of Ethiopian (EFO) and Indian (IFO) seeds contained ten components, with linoleic acid (50.12% in EFO and 57.69% in IFO) being the most abundant. Ethiopian seeds were used to extract the essential oil. 51.96% of the oil was hydrogenated monoterpenes. The main chemicals were p-cymene (36.76%) and thymoquinone (18.70%). There were fixed and essential oils in the Attarin oil sample. The main component was linoleic acid (14.61%), followed by p-cymene (13.85%). The maximum antibacterial activity (MIC 6.25 µg/disc) was seen in both fixed and liquid oil samples against Escherichia coli and Pseudomonas aeruginosa. The best anti-<i>P. aeruginosa</i> action was attarin oil (MIC 12.5 µg/disc). Finally, the Sudanese market needs to standardise <i>N. sativa</i> seeds and oil.


2022 ◽  
Author(s):  
Dan-Adrian Corfar ◽  
Konstantinos Daniel Tsavdaridis

Hot-rolled steel Modular Building Systems (MBS) represent the highest level of Off-Site Con-struction (OSC) in which prefabricated, and often prefinished steel modules are delivered to site on a ‘just-in-time’ basis and assembled into complete building systems. Besides the already well-known advantages such as tight tolerance control, reduced on-site human intervention and speedier construction times, the context of the ongoing climate emergency has brought forward the connection between circular economy (CE) and opportunities of steel MBS for disassembly and reuse. However, the use of hybrid structural systems, the functionality of inter-modular connections, and the effects of complex and demanding load transfer paths often question the actual prospects of deconstruction, repair, relocation, or reuse. So far, inter-module connections have been heavily influenced by conventional design methods, relying on bolts, welds or even prestressing strands, which require laborious on-site tasks and simplifying design assumptions, often raising uncertainty about structural behaviour of modular buildings.In an attempt to mitigate limitations of existing systems, a new inter-module connection was envisaged, inspired from the inter-locking method of joining. At the forefront of the develop-ment process, topology optimisation (TO) was adopted in the conceptual design of the main component of the joint, assisting the morphogenesis process which provided the final configu-ration of the novel system. The structural performance of the newly proposed connection was assessed through a series of static monotonic and quasi-static cyclic FE analyses. Results re-vealed that in terms of load-bearing capacity, ductility and energy dissipation ability, the struc-tural behaviour of the new connection was comparable to that of other inter-module joints in literature, while managing to tackle their limitations by introducing both an easy-to-install and easy-to-disassemble configuration with promising opportunities for reuse, further demonstrat-ing that inter-locking joints could be worthy competitors for traditional means of attachment in the future of modular construction.


2022 ◽  
Vol 23 (1) ◽  
pp. 578
Author(s):  
Lenka Horníková ◽  
Kateřina Bruštíková ◽  
Sandra Huérfano ◽  
Jitka Forstová

The nuclear lamina is the main component of the nuclear cytoskeleton that maintains the integrity of the nucleus. However, it represents a natural barrier for viruses replicating in the cell nucleus. The lamina blocks viruses from being trafficked to the nucleus for replication, but it also impedes the nuclear egress of the progeny of viral particles. Thus, viruses have evolved mechanisms to overcome this obstacle. Large viruses induce the assembly of multiprotein complexes that are anchored to the inner nuclear membrane. Important components of these complexes are the viral and cellular kinases phosphorylating the lamina and promoting its disaggregation, therefore allowing virus egress. Small viruses also use cellular kinases to induce lamina phosphorylation and the subsequent disruption in order to facilitate the import of viral particles during the early stages of infection or during their nuclear egress. Another component of the nuclear cytoskeleton, nuclear actin, is exploited by viruses for the intranuclear movement of their particles from the replication sites to the nuclear periphery. This study focuses on exploitation of the nuclear cytoskeleton by viruses, although this is just the beginning for many viruses, and promises to reveal the mechanisms and dynamic of physiological and pathological processes in the nucleus.


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