Neat Samples Research Articles

Structural and Optical Studies of Hydrothermal Synthesis of Yttrium Oxide Nanoparticles: in vitro Antioxidant Activity

Nanoparticles research is at the forefront because of its enormous technological potentialities. Through the hydrothermal method, yttrium oxide nanoparticles having multiform morphologies are successfully synthesized. The morphology, structure, photoluminescence properties, and functional groups of these nanoparticles were studied through scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), Fourier-transform infrared spectrometry (FTIR), photoluminescence spectroscopy (PL) and UV-Visible (UV-Vis) analyses. The XRD results showed that the neat samples have cubic Y2O3 structure. SEM micrographs revealed that the samples comprised aggregated nanoparticles having different sizes and shapes. The UV-Vis spectra indicated that the absorption peak position shifted towards the lower wavelength with a decrease in the particle size because of the changing surface structures and morphologies. Photoluminescence spectra showed a PL emission with a broad peak at approximately 564 nm, when the sample was excited by 280 nm wavelength. FTIR and EDAX spectra confirmed the presence of metal oxides. Yttrium oxide nanoparticles can counteract the influence of oxidative metabolites and present an antioxidant activity with the IC50 of 86.84 μg/mL. These properties indicated that these nanoparticles have a potential in biomedical and optoelectronic applications.

Effect of sisal fiber on retrogradation and structural characteristics of thermoplastic cassava starch

Thermoplastic cassava starch (TPS)/sisal fiber (SF) composites were prepared by the melting method. The effect of SF on the retrogradation kinetics, morphology and size of spherulites, molecular interactions, short-range molecular structure, and crystal type of TPS was investigated. The results indicate that the retrogradation degree and rate of TPS increase with the addition of SF, and the spherulites become clearer and denser. The neat TPS sample forms an A-type crystal through double helix structure and a V-type crystal through single helix structure. After the addition of SF, the A-type crystal of the TPS/SF composite decreases and the V-type crystal increases. With the further increase of SF content, the TPS/SF composite mainly presents the V-type crystal. The TPS/SF composite has higher crystallinity, but smaller crystal size and interplanar spacing. The storage modulus, loss modulus, and glass transition temperature (Tg) of TPS get enhanced with the addition of SF.

Phosphorylated Salicylic Acid as Flame Retardant in Epoxy Resins and Composites

A novel, versatile flame retardant substructure based on phosphorylated salicylic acid (SCP) is described and used in the synthesis of new flame retardants for HexFlow® RTM6, a high-performance epoxy resin used in resin transfer molding processes as composite matrix. The starting material salicylic acid can be obtained from natural sources. SCP as reactive phosphorus chloride is converted with a novolak, a novolak containing 9, 10-dihydro-9- oxa-10-phospha-phenanthrene-10-oxide (DOPO) substituents or DOPO-hydroquinone to flame retardants with sufficient thermal stability and high char yield. Additionally, these flame retardants are soluble in the resin as well as react into the epoxy network. The determined thermal stability and glass transition temperatures of flame retarded neat resin samples as well as the interlaminar shear strength of corresponding carbon fiber reinforced composite materials showed the applicability of these flame retardants. Neat resin samples and composites were tested for their flammability by UL94 and/or flame-retardant performance by cone calorimetry. All tested flame retardants decrease the peak of heat release rate by up to 54% for neat resin samples. A combination of DOPO and SCP in one flame retardant shows synergistic effects in char formation and the mode of action adapts to neat resin or fiber-reinforced samples, so there is efficient flame retardancy in both cases. Therefore, a tailoring of SCP based flame retardants is possible. Additionally, these flame retardants efficiently reduce fiber degradation during combustion of carbon fiber-reinforced epoxy resins as observed by scanning electron microscopy and energy dispersive X-ray spectroscopy.

Direct oral anticoagulants‐Remove versus Taipan snake venom time for detection of a lupus anticoagulant in patients taking oral direct factor Xa inhibitors

BackgroundThe optimal method of detecting a lupus anticoagulant (LA) for patients taking direct factor Xa inhibitor (DFXaI) direct oral anticoagulants (DOACs) remains controversial. Methods include charcoal adsorption of the DOACs to allow testing with the activated partial thromboplastin time (APTT) and dilute Russell viper venom time (dRVVT), or use of the DFXaI‐insensitive Taipan snake venom time (TSVT) and Ecarin time (ET) assays on neat plasma. ObjectivesThe objective was to compare the utility of APTT and dRVVT analysis following DOAC Remove against TSVT/ET on untreated plasma for LA detection in spiked plasmas and routine clinical samples for patients on DFXaIs. Patients/methodsVarious LA‐negative and LA‐positive samples were assayed by APTT, dRVVT, and TSVT/ET, and then separately spiked with rivaroxaban, apixaban, and edoxaban calibrators to a concentration of ~190 ng/ml and the assays repeated on spiked plasma before and after DOAC Remove treatment. Testing of 284 consecutive samples from DFXaI‐anticoagulated patients by APTT/dRVVT and TSVT/ET before and after DOAC Remove treatment was undertaken. ResultsIn the spiking model, we found that both TSVT/ET and DOAC Remove strategies generally distinguished LA‐negative and LA‐positive samples, but some false‐positive LA results occurred. In the investigation of 284 consecutive patient samples on DFXaIs, the percentage agreement for LA detection in neat samples tested by TSVT/ET versus APTT and dRVVT after DOAC Remove treatment was 90% (Cohen kappa 0.12). ConclusionOur data highlight uncertainty and disagreement for testing LA in patients on DFXaI. Further studies are required.

Discrimination of commercial ibuprofen tablets by using a button sample holder and mid-infrared spectroscopy.

Infrared spectra obtained from commercial ibuprofen tablets are categorized by using principal component analysis. A stainless steel abrasive button is used to sample the coatings and interiors of ibuprofen tablets with three different formulations. Rubbing the button wire mesh surface across tablet surfaces removes material for analysis. Small fragments are retained within mesh void spaces and larger fragments are swept away prior to analyses. Infrared spectra for tablet coatings exhibit significant differences and can be used for identification. Tablet interior compositions consisting primarily of ibuprofen from different manufacturers are more distinguishable from pre-processed spectra than from spectrum second derivatives. The speed and sensitivity afforded by this methodology suggests that rapid detection of counterfeit pharmaceuticals based on mid-infrared spectroscopy measurements of microgram quantities of material removed with a button sample holder is feasible.

High- and low-velocity impact experiments on treated STF/3D glass fabrics

In this study, the ballistic and cushioning behavior of Pure Shear Thickening Fluid (PSTF) and Treated Shear Thickening Fluid (TSTF) impregnated 3D glass fabrics were investigated by using a gas gun and drop-weight impact test, respectively. The PSTF was prepared by dispersing fumed silica nanoparticles in PEG in the mass fraction of 30 wt%, and the TSTFs were prepared in the mass fraction of 30 wt%, 40 wt%, 50 wt%, and 60 wt% by modifying the PSTF and treating the silica surface with 3-Aminopropyl triethoxysilane (APTES). The drop-weight impact test results showed that the applied impact force on the five-ply TSTF impregnated sample is less than the force applied on the five-ply PSTF impregnated sample in the same mass fraction (30 wt%) and this sample demonstrates better-cushioning performance. The five-ply 3D glass fabric impregnated with the TSTF 50 wt% demonstrated the best cushioning performance and reduced the applied peak force by 35% and 60% respectively, compared to the five-ply neat sample and the steel plate (rigid test case). According to the ballistic test, the penetration depth was decreased by impregnating the samples with the PSTF 30 wt%. By modifying the silica and using the high concentration TSTFs (up to a concentration of 50 wt%), the ballistic resistance of the samples was increased. However, the ballistic performance of the TSTF 60% impregnated did not show much improvement.

Silver nanoparticles decorated polyhedral oligomeric silsesquioxane nanocages as an effective nanoadditive for improved structural and biological properties of poly(vinylidene fluoride-co-hexafluoropropylene) nanofiltration membrane

Incorporation of a well-defined functionalized polyhedral oligomeric silsesquioxane (POSS) into a polymer matrix represents a new chemical advancement for applied membrane technology. Herein, POSS nanocages densely decorated with silver (Ag) nanoparticles (NPs) were used as effective hydrophilic and antibacterial additive. In this work, first, a facile and simple chemical reduction strategy is employed to prepare the organic–inorganic hybrid nanocages of Ag@POSS by in situ reduction of the Ag NPs with octa-ammonium molecules of POSS. These Ag@POSS nanocages were added as nanofiller for the fabrication of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanohybrid membrane. Ag@POSS nanocages added PVDF-HFP membrane exhibited formation of homogeneous and stable films compared to the unmodified polymeric membranes due to van der Waals and hydrogen bonding interactions of Ag@POSS with –CH2 groups and F atoms of polymer matrix. Pure water flux measurement of nanohybrid membrane showed that Ag@POSS PVDF membrane displays dramatic increase in the permeability (1,554.6 L/m2/h) and hydrophilicity (67°) properties. Furthermore, antibacterial activity and protein adsorption capacity of Ag@POSS PVDF membrane were evaluated by quantitative analysis of living bacterial cells and protein mass adsorption using Escherichia coli and bovine serum albumin (BSA) protein, respectively. The E. coli colonies (108 CFU/mL) on the Ag@POSS PVDF membrane samples tended to decline with 0.5 × 106 CFU/mL compared to neat PVDF-HFP membrane sample (1.3 × 108 CFU/mL). The improvement in biological properties of Ag@POSS PVDF membrane is due to the formation of Ag-octamine on the surface of POSS which lead to the formation of a boundary protection film. The surface–modified POSS with Ag NPs can be used as a nanofiller in polymeric membrane for developing high-performance permeable nanofiltration and antibacterial/antifouling polymeric membranes.

On comparison of recycled LDPE and LDPE–bakelite composite based 3D printed patch antenna

In the past two decades number of studies have been reported on the use of thermoplastics as a substrate for 3D printed patch antennas. However, no work has been reported on the thermoplastic-thermosetting composite-based substrate for 3D printed patch antennas and their mechanical, morphological, rheological, and radiofrequency (RF) characterization for sensing applications. In this study low-density polyethylene (LDPE) and LDPE-5% bakelite (BAK) composite-based patch antenna (resonating frequency 2.45 GHz) were printed (for secondary recycling) on fused deposition modeling (FDM) setup. The RF characteristics were measured using a vector network analyzer (VNA). Ring resonator test was used for measuring the dielectric properties of substrates (which suggests that the dielectric constant ([Formula: see text]) and loss tangent ([Formula: see text]) for LDPE was 2.282 and 0.0045, whereas for LDPE-5%BAK the calculated [Formula: see text] and [Formula: see text] was 2.0663, 0.0051 respectively). This study highlights that for the LDPE-5%BAK composite there was a marginal increase in the size of the patch antenna; but this resulted in improved transmittance, gain, and return loss for typical sensor applications. As regards to printability of substrate, 5% BAK resulted in a melt flow index (MFI) of 9.96 g/10 min in contrast to 12.208 g/10 min for a neat LDPE sample. The selected LDPE-5%BAK composite resulted in peak strength (PS) and break strength (BS) of 16.08 MPa and 14.47 MPa (at 180 °C screw temperature, 110 rpm, and 11 kg load) while processing with a twin-screw extruder (TSE), which was observed better than the neat LDPE (PS 11.98 MPa, BS 10.79 MPa). The results were supported with porosity (%), surface roughness (Ra) analysis based upon scanning electron microscopy (SEM) and bond strength using attenuated total reflection (ATR) based Fourier transformed infrared (FTIR) analysis.

Evaluating the therapeutic effect and toxicity of theophylline in infertile men with asthenoteratozoospermia: a double-blind, randomized clinical trial study

Theophylline as a cyclic adenosine monophosphate (cAMP) phosphodiesterase inhibitor (cAMP-PDEI) elevates cAMP levels. We aimed to evaluate the therapeutic effect and toxicity of theophylline on the sperm parameters, oxidative stress (OS), and inflammation in asthenoteratozoospermic men. Sixty asthenoteratozoospermic patients were divided into groups of placebo and theophylline (200 mg/day). After 3 months of oral treatment, sperm parameters, viability, and DNA fragmentation were analyzed by the CASA system, eosin nigrosin staining, sperm DNA fragmentation kit, respectively. The seminal plasma level of reactive oxygen species (ROS) of neat semen samples, malondialdehyde (MDA), total antioxidant capacity (TAC), tumor necrosis factor alpha (TNF-α), and interleukin-10 (IL-10) was assessed. Data were analyzed statistically using the independent samples t-test and the paired t-test and the means were considered significantly different at p < 0.05. Sperm motility, viability, and the number of sperms with normal morphology and the seminal plasma level of TAC and IL-10 and also sperm DNA fragmentation increased significantly in the theophylline group compared to the placebo. The MDA, TNF-α, and ROS levels decreased significantly in the theophylline group compared to the placebo. Theophylline improved sperm parameters, reduced OS and inflammation, but also created genotoxicity and increased sperm DNA fragmentation. Therefore, to benefit from the desired effects of theophylline and inhibit the toxicity of it in the treatment of men with asthenoteratozoospermia, it is suggested to be used simultaneously with another antioxidant to protect sperm DNA from fragmentation.

A renewable lignin-derived bio-oil for boosting the oxidation stability of biodiesel

The valorisation of lignin is being increasingly recognised to improve the economics of pulp and paper making mills. In the present study, an integrated lignin–glycerol valorisation strategy is introduced with an overarching aim for enhancing the process value chains. LignoBoost kraft lignin was subjected to base-catalysed depolymerisation using glycerol as a co-solvent. The generated bio-oil was used as a renewable additive to biodiesel for enhancing its oxygen stability. The influence of three independent parameters including temperature, time and glycerol amount on lignin depolymerisation was investigated. Response surface methodology was applied to design the experiments and to optimise the process for maximising the yield and antioxidant impact of bio-oil. The results showed that glycerol has a positive qualitative and quantitative impact on the produced bio-oil, where an enhancement in the yield (up to 23.8%) and antioxidant activity (up to 99 min induction period) were achieved using the PetroOxy method (EN16091). The addition of 1 wt% bio-oil to biodiesel has led to an improvement in the oxidation stability over a neat sample of up to ∼340%, making it compliant with European standard (EN14214). The proposed process presents a biorefinery paradigm for the integrated utilisation of waste cooking oil, lignin and glycerol.

Fabrication of Al-Mg solid solution by friction stir selective alloying

This study reports the fabrication of an Al-Mg solid solution layer containing ∼2 at.% Mg on pure Al substrate by a solid-state processing technique called friction stir selective alloying. Accordingly, a machined groove on the surface of Al substrate was filled by a bulk Mg block and friction stir processing was applied to form Al-Mg solid solution. The XRD/EDS results revealed formation of solid solution structure in the stirred zone of the alloyed sample. Furthermore, the hardness of the prepared Al-Mg solid solution (∼55.8 HV) was more than twice greater than the hardness of the FSPed neat sample (∼25.0 HV).

Experimental Study on Puncture Resistance of 2D and 3D Glass Fabrics Reinforced with Shear Thickening Fluid (STF)

In this study, the quasi-static puncture resistance of neat and Shear Thickening Fluid (STF) impregnated Kevlar, 2D, and 3D-glass fabrics was investigated using a universal testing machine. For the synthesis of the STFs, silica nanoparticles were dispersed in polyethylene glycol (PEG) in the mass fraction of 20, 25, 30, and 35 wt% STF. The influence of the STF concentration on the puncture resistance of the impregnated 3D-glass fabrics was examined and compared with the neat samples. The results revealed the puncture resistance of the impregnated 3D-glass fabrics increases with raising the STF concentration from 20 to 30 wt% (637 to 688 N). However, the performance of the 35 wt% STF impregnated sample was reduced (657 N). The 30 wt% STF impregnated 3D-glass fabric showed the most puncture resistance, such that its peak force (688 N) was 17% higher than the neat case (590 N). The results were compared with those of Kevlar and four-ply 2D-glass fabrics, and it was observed that, the 30 wt% STF effect on the 3D fabrics was more evident than them. Unlike the 2D-glass fabrics, the bending angle (θ) for the 3D-glass fabrics decreased by 10° and as a result their flexibility lessened. The thickness of the impregnated 2D-glass fabric increased more than the 3D fabrics (27% vs. 4%).

Extraction of intrinsic effects of glassy domain cross-linking on the tensile properties of ABA block copolymer elastomers via photo cross-linking approach

Chemical or physical cross-links into the A glassy domains have been reported to enhance mechanical properties for glassy-b-soft-b-glassy ABA triblock copolymer-based elastomers. However, no reports dealt with the pure effects of the domain cross-linking, since the cross-linking processes inevitably altered the morphological characteristics. This study extracts the intrinsic effects of domain cross-linking on the tensile properties based on the ABA triblock copolymer with the A blocks cross-linked via photo cross-linking without heat and cross-linker molecules. Differential scanning calorimetry, viscoelasticity measurements, and small-angle X-ray scattering (SAXS) with a model function analyses were used to confirm preservation of the segmental dynamics of the B block and the morphology of the self-assembled structure after cross-linking, which are all important for a fair discussion. Tensile properties were then investigated by simple elongation and cyclic tests, revealing that the domain cross-linking enhanced the stress in the small deformation region and the recovery property primarily. These changes of the tensile properties were discussed in terms of the deformation resistance of the micro-phase separated structure based on the SAXS data under elongation. The superiority or inferiority of cross-linking the end block domains or middle block strands for mechanical property enhancement was interpreted based on the observed difference between the neat and cross-linked samples. In the last section, effects of domain photo cross-linking for the different morphologies were also examined. Throughout the article, this study can provide new and essential knowledge of the mechanical properties of block copolymer-based materials, and some valuable hints for further modification of the physical properties of these materials.

Synthesis and Physical Characterization of PMMA/PP and PMMA/ PAN Composites for Denture Applications

This study involves on manufacture of denture base resin with advanced physical properties through the addition of two type of synthetic fibers used as reinforcing materials polypropylene (PP) and Poly acrylonitrile (PAN). In this research, groups of three samples of both PMMA/PP and PMMA/PAN composites were prepared with the selected fiber weight ratios of 1.5, 3.5, 5.5 and 7.5 %Wt. Physical properties such as water absorption, thermal conductivity and density were evaluated under normal conditions. The chemical bond structure was also investigated for all samples using FTIR test. The results showed that when fibers ratio increased until 7.5 %Wt., the water absorption increases, as well for each fiber which was over 0.6% compared to the 0.3% of the neat sample. A noticeable decrease in the thermal conductivity property from 0.33 W/m.K for PMMA/PP and 0.24 W/m.K for PMMA/PAN comparing to 0.46 W/m. K of the neat polymer was revealed. As for the density results, it was found that when the fibers ratios were increased, the sample density slightly decreased and reached 1.09 g/cm3 for PMMA/PP and 1.1 g/cm3 for PMMA/PAN at the maximum fibers rate. FTIR results indicated there was no new peaks appeared after reinforcement with both fibers. This could refer to the good physical bond between the mixtures, no new material formed.

Valorization Strategy for Leather Waste as Filler for High-Density Polyethylene Composites: Analysis of the Thermal Stability, Insulation Properties and Chromium Leaching.

Leather waste (BF) and high-density polyethylene (HDPE) were compounded in a lab scale internal mixer and processed by means of injection molding. In this study, leather waste and HDPE composites were characterized by instrumental techniques such as differential scanning calorimetry (DSC), thermo-gravimetric Analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). Physical integrity of composites against chemical exposure and chromium-leaching properties of the composites were also investigated. This study shows that the incorporation of 30% leather waste fiber into HDPE composites decreases the thermal conductivity of the composite samples by 17% in comparison to that of neat HDPE samples. Composites showed no thermal degradation during processing cycle. Strong interfacial bonding between leather waste and polymer results in comparable low-leachate levels to maximum allowed concentration for nonhazardous waste, and good chemical resistance properties. The BF/HDPE composites could be a promising low-cost alternative in industrial application areas of HDPE, where high-mechanical strength and low-thermal conductivity is required.

Detection of syrup adulterants in manuka and jarrah honey using HPTLC-multivariate data analysis.

High-Performance Thin-Layer Chromatography (HPTLC) was used in a chemometric investigation of the derived sugar and organic extract profiles of two different honeys (Manuka and Jarrah) with adulterants. Each honey was adulterated with one of six different sugar syrups (rice, corn, golden, treacle, glucose and maple syrups) in five different concentrations (10%, 20%, 30%, 40%, and 50% w/w). The chemometric analysis was based on the combined sugar and organic extract profiles’ datasets. To obtain the respective sugar profiles, the amount of fructose, glucose, maltose, and sucrose present in the honey was quantified and for the organic extract profile, the honey’s dichloromethane extract was investigated at 254 and 366 nm, as well as at T (Transmittance) white light and at 366 nm after derivatisation. The presence of sugar syrups, even at a concentration of only 10%, significantly influenced the honeys’ sugar and organic extract profiles and multivariate data analysis of these profiles, in particular cluster analysis (CA), principal component analysis (PCA), principal component regression (PCR), partial least-squares regression (PLSR) and Machine Learning using an artificial neural network (ANN), were able to detect post-harvest syrup adulterations and to discriminate between neat and adulterated honey samples. Cluster analysis and principal component analysis, for instance, could easily differentiate between neat and adulterated honeys through the use of CA or PCA plots. In particular the presence of excess amounts of maltose and sucrose allowed for the detection of sugar adulterants and adulterated honeys by HPTLC-multivariate data analysis. Partial least-squares regression and artificial neural networking were employed, with augmented datasets, to develop optimal calibration for the adulterated honeys and to predict those accurately, which suggests a good predictive capacity of the developed model.

CAN MICROFLUIDIC SPERM SORTING HELP SEPARATION OF SPERMS WITH GOOD QUALITY DNA?

It is evident that raised sperm DNA Fragmentation (SDF) negatively affects the reproductive outcomes. Management for raised sperm DFI to optimize reproductive outcomes is still elusive. Microfluidic sperm sorting and Magnetic cell sorting are few of the newer methods employed to obtain sperms with good DNA and optimize reproductive outcomes. However, there is further need for clinical validation of these newer interventions. In Individuals with raised SDF, will sperm sorting with Microfluidics principle help in obtaining sperms with good quality DNA? This was an observational pilot study performed at our private fertility unit from August 2020 to March 2021. Couples with raised SDF (>15%) were recruited and offered microfluidic sorting (n=34). Couples with history of one failed IVF cycle were offered testing for SDF. Individuals with SDF > 15% were included in the study. SDF testing was done with SCSA flow cytometer method. On the day of oocyte retrieval male partners were advised to come with 48hrs abstinence and semen sample was obtained by masturbation. Small aliquot of ejaculated neat sample was sent for SDF testing. Zymot multi ZMH0850 Microfluidic chamber was used for this study. Protocol for microfluidic sorting was done as per the manufacturer’s instruction. Post microfluidic processing the sample was sent to SDF testing again. SDF values of neat and processed samples were compared. Appropriate consents were obtained from the couples that were recruited in this study after thorough counseling. Mean of SDF of neat samples was 24%. Mean of SDF of microfluidic-sorted samples was 3.1%. SDF values of all samples after microfluidic sorting were less than 10%. Paired “t” test was done and the outcomes were statistically significant. There seemed a significant reduction in SDF values with microfluidic sperm sorting. Microfluidics Sperm Sorting seems to be a promising intervention to obtain sperms with good DNA quality. Microfluidics Sperm Sorting seems to be a beneficial intervention to optimize sperm selection with good DNA quality for Individuals with raised sperm DFI.

Tensile behavior of environmental pollutant crumb rubber filled epoxy composites

Tensile test is conducted on environmentally pollutant crumb rubber/epoxy composite. Crumb rubber particles with different volume fractions (10, 20 and 30%) are reinforced with epoxy matrix. Stress-strain curves reveal brittle fail for all the samples. Crumb rubber filled epoxy composites reveal higher modulus (13%–28%) and strength (28%–44%) than neat epoxy sample. Epoxy with 30 volume % of crumb rubber depicts higher modulus and strength compared with all other compositions, exemplifying use of crumb rubber for utilarian applications. Crumb rubber/epoxy composites register higher specific modulus and strength for all compositions in comparison with neat epoxy. Scanning electron micrographs of test samples are used to analyze property - composition correlations. Finally, property map is plotted to compare the results of present study with existing ones to highlight the efficacy of the proposed composites.

Improved tensile and impact responses of microcellular PP/γ-irradiated elastomer blends corroborating microstructure and crystallinity

The purpose of the present study was to compare the tensile and impact performances of foams of PP/γ-irradiated elastomer blends with that of the foams of PP/unirradiated elastomer blends. Furthermore, the morphological and crystallinity studies were considered to correlate the tensile and impact behavior of foams. Foaming of blends was carried out in a batch foaming set up with supercritical CO2. A continuous decrease in crystallinity was observed for both types of blends along with the relative change in the number of different crystal forms. Remarkable necking phenomenon and strain-induced crystallization were observed in foams. The tensile modulus of samples significantly increased up to 3 times than that of the neat samples at lower temperature foaming. The maximum modulus of foams was attained for the blends with 10% irradiated elastomer concentration. The impact strength of foam was also improved at the same condition, where the tensile modulus was highest.

P–025 Sperm selection using a modified “swim up” technique in absence of sperm centrifugation improve sperm DNA fragmentation and decreases miscarriage rate

Abstract Study question Is it useful to avoid sperm centrifugation in laboratory routine work to improve sperm quality and reproductive outcome in Assisted Reproduction Techniques (ART)? Summary answer Exclusion of sperm centrifugation for sperm selection using neat sperm samples (IO-lix), increases sperm quality in the collected subpopulation decreasing miscarriage rate after using ICSI. What is known already Inclusion of sperm centrifugation in ART is an aggressive intervention for sperm selection with ineludible production iatrogenic damage affecting sperm integrity. The application of IMSI, PICSI or microfluidic devices avoid sperm centrifugation and may improve the quality of the subsample obtained. However, these methodologies may result time consuming, expensive or producing poor results when the quality of the sperm is limited. We have already shown that a modified swim-up avoiding centrifugation (called IO-lix) is a low-cost and efficient alternative to microfluidic devices, recovers 100 times more concentration and reduces sperm DNA fragmentation with no significant differences to other methodologies. Study design, size, duration This is a retrospective study from 2018 to 2020 which includes patients with an average of age of 38.2 years using their own oocytes with ICSI as fertilization technique. Two aleatory groups of patients were made: Group 1: 88 cycles with 503 fertilized oocytes and 206 blastocysts were obtained with sperm samples processed by IO-lix and Group 2: 303 cycles, 1451 fertilized oocytes and 591 blastocysts using a standard “swim up” technique to process sperm. Participants/materials, setting, methods A total of 391 ICSI cycles were included in this retrospective study. The male factor was similar in both groups and they showed altered SDF previously to the cycle. We compared data of the motility and SDF of sperm samples before and after applying IO-lix and we analyzed by X2 contingence test differences on miscarriage rates between groups 1 and 2. Main results and the role of chance General sperm parameter changes after IO-lix showed that averaged sperm concentration observed in neat ejaculated samples was 62M/SD=46.4. Values obtained after IO-lix in the same samples were 12.3M/SD8.0. Averaged sperm motility in neat samples was 54%/SD=9.3 and 70.9%/SD=13.2 after IO-lix. Finally, sperm DNA fragmentation in neat samples was 35.8%/SD17.3, while these values decreased to 9.2%/SD=3.9 after IO-lix. About reproductive outcome results, significant differences were not obtained on the development to blastocyst stage rate comparing both groups (X2=0.003; p value = 0.954; Alpha 0.05). In the case of IO-lix processed samples, the pregnancy rate was 59.42% in Group 1 and 44.72% in Group 2 (X2=0.651; p value =0.419; Alpha 0.05). A total of 9 miscarriages of 41 clinical pregnancies (21.95%) were observed after IO-lix, while this number increases to 59 out of 123 clinical pregnancies, which means the 47.96% of the embryo transfers, when “swim-up” was used. In this case significant differences were obtained (X2=3.935; p value = 0.0.047; Alpha 0.05). Limitations, reasons for caution Being a pilot study aimed to understand the results of IO-lix in ART, correlations have not been stablished between the levels of sperm improvement after IO-lix and paired results of ART. This study would be necessary, specially to identify the possible origin of miscarriage associated to the male factor. Wider implications of the findings: Elimination of sperm centrifugation using a combined strategy of gradients and “swim-up” for sperm isolation, reduce miscarriage rate and produce equivalent results of blastocyst development to those obtained with “swim-up”. Being a cost-effective and improving laboratory workload, its use for sperm selection is recommended. Trial registration number Not applicable