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Dissimilar laser welding of martensitic AISI 1060 carbon steel and Duplex Stainless Steel 2205 was performed based on an experimental and numerical study. The experiments were then conducted based on central composite design experiments (CCD) and analyzed via the response surface methodology (RSM) by considering the effect of laser welding process parameters (incident laser power, speed of welding, nozzle distance and deviation of laser beam) on the weld joint characterization. The experimental results showed that the laser power had a remarkable effect on the melt pool depth. By increasing the laser power from 250 to 450 W at the focal point position, the melt pool depth was increased from 0.4 to 1.4 mm. The microstructure of the molten pool was mainly composed of the solidification of duplex stainless steel (DSS). The molten pool microstructure included columnar dendritic and inter-dendritic microstructures at the boundary fusion line of the toward duplex 2205 base metal. The cellular microstructure with epitaxial grain growth at the center of the molten pool was then formed. According to the numerical simulation results, by increasing the laser power from 250 to 400 W, the extension of high temperature region (more than 1800 °C) was raised to about 150 percent at both depth and width. According to the tensile tests results, the joint fracture surface of the carbon steel side of the joint showed a brittle fracture mechanism due to the martensitic nature of the microstructure of carbon steel, while the fracture cross-section of the DSS side of the joint had a mostly ductile fracture mode, as compared to carbon steel. By increasing the laser beam energy density to more than 0.05 MW/cm2, a coarse grain cellular dendrite was formed at the fusion zone toward AISI 1060 steel along with tempered martensitic microstructure at the heat affected zone of the AISI1060 base metal. This led to the transformation of the joint fracture mechanism from a brittle one to a ductile one. The maximum tensile stress of the dissimilar joints was lower than that of both base metals, although the maximum tensile strength of 550 MPa was obtained at the focal point position and the laser power of 450 W. By increasing the laser power from 400 to 450 W, the microhardness at the region near the fusion line of the duplex stainless steel was increased by about 50 HV, while at the center of the fusion zone, the maximum increase rate reached to 250 HV.

Welding with fiber laser for two distinct stainless steel types was performed to join with the martensitic carbon steel (AISI 1060) in order to assess the effect of laser welding operating parameters for two dissimilar materials on the weld characterization thorough experimental design method and numerical investigation. A full central composite design (CCD) matrix in accordance with the response surface methodology (RSM) was developed to represent the responses variations by equations including quadratic and nonlinear interaction terms. Different laser welding parameters were taken into account, such as laser power, linear speed of welding, focal distance of the beam, and beam deviation. The responses considered were the temperature field next to the melt pool border line, the maximum penetration depth of the fusion zone and the ultimate tensile strength of the dissimilar weld joint. Additionally, the variation of the microstructure fusion zone and adjacent areas and failure mechanism of the weld joint were evaluated. The experimental results indicate that the temperature field measured at the vicinity of the melt pool fusion line with both 304 and 420 stainless steel which primarily influenced by the incident power of the laser and linear velocity of beam, respectively. Additionally, the numerical simulation results are in good agreement with temperature experimental results at vicinity of fusion line where the temperature measured, experimentally. Apart from this, at the center of the fusion zone, the temperature clearly predicts via numerical simulation results which is not possible to assess experimentally. A clear comparison between the temperature distribution with different joint configuration illustrates that distinct relation between the temperature variation rate and different thermal conductivity coefficient of AISI 1060 with different AISI 304 and 420 joint configuration resulted different temperature distribution. The weld joint microstructure for 420 stainless steel–AISI 1060 steel joint at fusion boundary zone consists of columnar dendrites and skeletal columnar ferrite. At the center of fusion zone, a cellular-type structure is seen. For 304 stainless steel joint, the fusion zone has composed of a remarkable part of skeletal delta-ferrite and dendritic microstructure at austenite matrix microstructure. The fracture section of 304 steel has a ductile fracture and the depth of fracture dimples and cavities toward 304 stainless steel are higher than AISI 1060 steel.

In order to establish the dynamic constitutive model of 1060 aluminum material, the quasi-static tensile mechanical properties of 1060 aluminum in a temperature range from 25 ℃ to 300 ℃ were investigated by using a universal material testing machine, and the dynamic tensile mechanical properties of 1060 aluminum in a strain rate range from 0. 01 s -1 to 4 922 s -1 were also investigated by using a Hopkinson pull rod device. Based on the Johnson-Cook constitutive model and test results, the dynamic mechanical properties of the 1060 aluminum were fitted to obtain the material's constitutive parameters. In order to verify the accuracy of the constitutive model, the impact deformation test and impact deformation simulation analysis of 1060 aluminum thin plate structure were carried out respectively. The results show that the 1060 aluminum exhibits obvious strain hardening characteristics and strain rate strengthening effects when the strain rate changes from quasi-static to high strain rate, the true stress are increases with the increase of strain rate under the same ture strain, and the material exhibits low strain rate sensitivity in the range of high strain rate. In addition, the 1060 aluminum exhibit significant thermal softening effect, the yield strength of the material decreases with the increase of temperature. Besides, the identified Johnson-Cook constitutive model can be used to simulate the deformation of 1060 aluminum sheet structure under impact load, the relative error is only 2. 01% ~ 8. 86%, the results indicate that the established models can predict the tensile mechanical response of the 1060 aluminum under a complex stress state. [ABSTRACT FROM AUTHOR]

Resistance seam welding additive manufacturing (RSAM) is a new solid-state additive manufacturing technique that utilizes pulsed current and pressure to welding powders layer by layer. In this study, Al1060 powder was employed as the raw material to prepare R0 and R10 samples through RSAM technology and subsequent repeated welding processes, respectively. The results showed that, compared to R0, the grain size of the R10 sample decreased from 34.3 μm to 8.7 μm, and the dislocation density increased from 4.355 × 1014 to 9.436 × 1014 m−2. Additionally, due to the additional heat and pressure from repeated welding, the porosity decreased from 0.998% to 0.017%, the ultimate tensile strength and elongation improved from 63.5 ± 0.5 MPa and 4.5 ± 0.1% in R0 to 93.3 ± 0.5 MPa and 34.3 ± 0.1% in R10. The improvement in mechanical properties is primarily due to the combined effects of grain refinement, dislocation strengthening, and pore self-healing. This study introduces a feasible new approach for additive manufacturing of aluminum alloys and other materials that is difficult to be additively manufactured by other methods.

Yea-Jin Lee,1,2 Namgue Hong,2 Eun Seo Choi,3 Sun-Hyang Choi,2 Eun Young Kim,2 Hyeong Ju Park,4 Jin-Chul Ahn1,2 1Department of Medicine, Dankook University, Cheonan-si, 31116, Republic of Korea; 2Medical Laser Research Center, Graduate School of Medicine, Dankook University, Cheonan-si, 31116, Republic of Korea; 3Department of Physics, Chosun University, Gwangju, 61452, Republic of Korea; 4Bio&Health Photonics Research Center, Korea Photonics Technology Institute, Gwangju, 61007, Republic of KoreaCorrespondence: Hyeong Ju Park; Jin-Chul Ahn, Email phj020603@kopti.re.kr; jcahn@dankook.ac.krPurpose: To evaluate the efficacy and safety of abdominal fat reduction in mini-pigs, utilizing at 1060 nm diode laser with a wavelength of 1060 nm.Patients and Methods: The laser system non-invasively disrupts adipose tissue; its effectiveness and safety were evaluated by ultrasound imaging and histological analysis. Laser irradiation was performed with various powers, and the cooling function was activated to prevent skin surface damage.Results: The dermal tissue temperature increased to at least 43°C during laser exposure, leading to a decrease in abdominal fat thickness after 30 days. Blood tests revealed no significant changes in kidney and liver function but showed increased blood levels of nonessential free acids (NEFAs), likely due to the release of fatty tissue-derived free fatty acids. Histological evaluation demonstrated rapid transformation of adipose tissue into collagen, muscle fibers, and intracellular fibrous tissue.Conclusion: The 1060 nm laser showed promise as a non-invasive and safe tool for reducing abdominal fat.Keywords: diode laser, fat, abdominal, non-invasive, preclinical

Abstract Background Structural variations (SVs) have significant impacts on complex phenotypes by rearranging large amounts of DNA sequence. Results We present a comprehensive SV catalog based on the whole-genome sequence of 1060 pigs (Sus scrofa) representing 101 breeds, covering 9.6% of the pig genome. This catalog includes 42,487 deletions, 37,913 mobile element insertions, 3308 duplications, 1664 inversions, and 45,184 break ends. Estimates of breed ancestry and hybridization using genotyped SVs align well with those from single nucleotide polymorphisms. Geographically stratified deletions are observed, along with known duplications of the KIT gene, responsible for white coat color in European pigs. Additionally, we identify a recent SINE element insertion in MYO5A transcripts of European pigs, potentially influencing alternative splicing patterns and coat color alterations. Furthermore, a Yorkshire-specific copy number gain within ABCG2 is found, impacting chromatin interactions and gene expression across multiple tissues over a stretch of genomic region of ~200 kb. Preliminary investigations into SV’s impact on gene expression and traits using the Pig Genotype-Tissue Expression (PigGTEx) data reveal SV associations with regulatory variants and gene-trait pairs. For instance, a 51-bp deletion is linked to the lead eQTL of the lipid metabolism regulating gene FADS3, whose expression in embryo may affect loin muscle area, as revealed by our transcriptome-wide association studies. Conclusions This SV catalog serves as a valuable resource for studying diversity, evolutionary history, and functional shaping of the pig genome by processes like domestication, trait-based breeding, and adaptive evolution.

الملخص: مثَّل القرن الحادي عشر الميلادي/ الخامس الهجري مرحلة حاسمة في تاريخ جورجيا، إذ كان على خلفاء الملك باجراط الثالث Bagrat III (975- 1014م) مواصلة جهوده لإتمام الوحدة السياسية لمملكة الكرج، لكنهم اصطدموا بطموح الأمراء الكرج المحليين وأطماع البيزنطيين في بلادهم، في الوقت الذي بدأ فيه السلاجقة يبحثون عن موطأ قدم في القوقاز. وسوف يناقش البحث أهم الظروف السياسية التي مرت بها جورجيا على الصعيدين الداخلي والخارجي بدءًا من عام 1027م، وهو العام الذي تولي فيه الملك باجراط الرابع Bagrat IV (1027- 1072م) حكم مملكة الكرج حتى عام 1060م الذي شهد نجاحه في التغلب على ألد خصومه الأمير الإقطاعي ليباريت الرابعLiparit IV رجل بيزنطة الأول في القوقاز في تلك المرحلة؛ وذلك من خلال "حولية كارتلي" الكرجية لمؤرخ مجهول. Abstract: The eleventh century A.D. / fifth century A.H. represented a decisive stage in the history of Georgia, as the successors of King Bagrat III (975-1014 A.D.) had to continue his efforts to complete the political unity of the Kingdom of Georgia, but they collided with the ambitions of the local Georgian princes and the colonial aspirations of the Byzantines in their country at a time when Seljuks began to seek a foothold in the Caucasus. The research will discuss the most important political conditions that Georgia went through, both domestically and internationally, from the year 1027 A.D., when King Bagrat IV (1027–1072) assumed control of the Kingdom of Georgia, until the year 1060 A.D., which witnessed his success in overcoming his staunchest opponent, the feudal prince Liparit IV, the main man of Byzantium in the Caucasus at that stage, through the Georgian Chronicle, "The Chronicle of Kartli," written by an anonymous historian.

The incidence of male infertility (MI) is rising annually. However, the lifestyle and occupational exposure factors contributing to MI remain incompletely understood. This study explored the effects of self-reported lifestyle and occupational exposure factors on semen quality. Among 1060 subjects invited to participate, 826 were eligible. The participants' general characteristics, lifestyle, and occupational exposure factors were collected immediately before or after semen evaluation through an online questionnaire. Initially, univariate analysis was used to investigate the relationship between the abovementioned factors and semen quality. The results indicated significant associations between low semen quality and various factors, including age, BMI, infertility type and duration, abstinence time, semen and sperm parameters, smoking, alcohol consumption, irregular sleep habits, and frequent exposure to high temperatures and chemicals at work ( p  < 0.05). Then, multivariate analysis was conducted to identify factors independently associated with low semen quality. Adjustment for relevant confounders was achieved by including factors with a p -value < 0.25 from univariate analyses as covariates in the binomial and ordered logistic regression models. The results suggested that alcohol consumption was a positive factor for sperm concentration (odds ratio [OR] = 0.60; 95% confidence interval [CI] = 0.36-0.99; p  = 0.045). The groups with a BMI ≥ 24 and <28 kg/m 2 showed a significant decrease in sperm progressive motility when compared to the reference group (BMI < 24 kg/m 2 ) (OR = 0.63; 95% CI = 0.46-0.87, p  = 0.005). In addition, the groups that drank green tea <1 time/week (OR = 1.52, 95% CI = 1.05-2.2) and 1-4 times/week (OR = 1.61, 95% CI = 1.02-2.54) exhibited significantly increased sperm DFI values compared with the group that drank green tea 5-7 times/week. In conclusion, these findings underscore the importance of maintaining a normal weight and regularly consuming green tea for men.

The Higher Regional Court has ruled in a proceeding for the enforcement of a foreign arbitral award that objections to the recognition of the arbitral award are not precluded if no appeal was filed in the issuing state. The arbitral award concerned a dispute between a Chinese applicant and a German respondent regarding the delivery of a production line. The court decided that the recognition of the arbitral award cannot be refused as there was no violation of the right to be heard. The appeal was successful, and the case was referred back to the Higher Regional Court as the matter was not yet ripe for final decision. [Extracted from the article]

Low formability, low productivity and forming quality are the main factors restricting the industrial application of single point incremental forming technology. Ultrasonic vibration was introduced into the single point incremental forming process to improve the forming limit of sheet metal by changing the deformation mechanism of material. A device combining ultrasonic vibration with plastic deformation processing technology and single point incremental forming was developed in this work. Taking cone parts of 1060 aluminum as the research object, the effects of ultrasonic vibration amplitude and frequency on equivalent stress and equivalent plastic strain in forming process were analyzed by combining numerical simulation and experimental research. Then, the forming angle of cone parts was used as the standard to study the influence of ultrasonic vibration parameters on formability. The results show that the equivalent stress decreased and equivalent plastic strain increased by superimposing ultrasonic vibrations, ultrasonic vibration can significantly change the formability and improve the forming limit of 1060 aluminum, the forming limit of 1060 aluminum can be maximized by selecting ultrasonic vibration parameters: amplitude 0.03 mm and frequency 30 kHz. [ABSTRACT FROM AUTHOR]

Non-thermal components in the intra-cluster medium (ICM), such as turbulence, magnetic field, and cosmic rays, imprint the past and current energetic activities of jets from active galactic nuclei (AGN) of member galaxies as well as disturbance caused by galaxy cluster mergers. Meter- and centimeter-radio observations of synchrotron radiation allow us to diagnose the nonthermal component. Here we report on our discovery of an unidentified diffuse radio source, named the Flying Fox, near the center of the Abell 1060 field. The Flying Fox has an elongated ring-like structure and a central bar shape, but there is no obvious host galaxy. The average spectral index of the Flying Fox is −1.4, which is steeper than that for radio sources seen at meter wavelengths. We discussed the possibilities of radio lobes, phoenixes, radio halos and relics, and an odd radio circle. In conclusion, the Flying Fox is not clearly explained by known radio sources. [ABSTRACT FROM AUTHOR]