AA5052-PVC-AA5052 (Al-PVC-Al) Sandwich Sheets Forming Analysis through In-Plane Plane Stretching Tests.

Sheet metal forming is one of the key processes for the automotive sector to be considered. Sheet metal formability is being tested as received, joining them with different welding/joining processes (i.e., tailored blanks) and making them as sandwich forms to reduce the total weight of the body. These sandwich formations of sheets are an advanced method by incorporating PVC/polymer sheets in between metal sheets with a suitable binder. The present work has investigated the formability of AA5052-PVC-AA5052 (Al-PVC-Al) sandwich sheets by considering the sheet rolling direction as a parameter. The mechanical properties of base metal and sandwich sheets were evaluated by conducting the uniaxial tensile tests. For forming behaviour of Al-PVC-Al sandwich sheets, in-plane plane stretching tests were performed on the universal tensile testing machine. From the results, it has been observed that 0-degree and 90-degree rolling direction of AA5052 sheets provided almost similar forming behaviour where the 45-degree rolling direction showed less formability. The limit strains (by which the forming limit curve has been developed and the safe and failure zones are separated) are 0.043, 0.038, and 0.043 of 0°, 45°, and 90°, respectively. Considering 0°-P-90°, 90°-P-90, 0°-P-45°, 0°-P-90°, and 45°-P-45° sandwich sheets with their corresponding limit strains of 0.060, 0.058,0.057, 0.052, and 0.050, a better formability is seen in 0°-P-90° sandwich, followed by 90°-P-90, 0°-P-45°, 0°-P-90°, and 45°-P-45°. The improvement in the formability is calculated as 28.33%, 25.86%, and 24.0% in comparison with the base metal in 0-degree, 90-degree, and 45-degree rolling directions and 0°-P-90°, 90°-P-90, and 45°-P-45° sandwich sheets.

Effect of chemical treatment on physio-mechanical properties of lignocellulose natural fiber extracted from the bark of careya arborea tree.

For the first time, the current work has carried out a chemical treatment of a novel ligno-cellulose fiber that is extracted from the bark of an unexplored plant of Careya arborea. Careya arborea (CA), a flowering tree known for its green berries, thrives in the Indian subcontinent and Afghanistan. This research was focused on extracting fibers from the bark of the Cary tree for the first time to corroborate the influence of chemical treatment on its different characteristics. These CA fibers have a high proportion of cellulose, consisting of 71.17 wt percent, together with 27.86 wt percent of hemicellulose, and a reduced density of 1140 kg/m3, making them a suitable candidate for creating lightweight applications in a variety of industries. Chemical treatment has done on the cay fiber with the concentrations of NaOH 5 (wt%), 10 (wt%), and 15 (wt%) solution mixture to improve their characteristics. Estimated the difference between Chemically processed and non-processed Cary fibers and corroborated in results. We performed a number of experiments, including FTIR, XRD, SEM, EDAX, AFM, and TGA, to fully comprehend the changing properties. Chemical testing showed that cellulose changed from its non-crystalline state to cellulose, proving that the treatment was successful in changing the fibre structure. Additionally, the thermo-gravimetric examination showed higher thermal stability 248 °C-325 °C and a rise in the crystallinity index, indicating the treated fibers' improved potential for high-temperature applications. The treated Cary fibers exhibited excellent surface properties, promising improved adhesion, mechanical performance, offering lightweight and sustainable solutions for diverse applications.

The effect of missing data and imputation on the detection of bias in cognitive testing using differential item functioning methods.

BACKGROUND: Item response theory (IRT) methods for addressing differential item functioning (DIF) can detect group differences in responses to individual items (e.g., bias). IRT and DIF-detection methods have been used increasingly often to identify bias in cognitive test performance by characteristics (DIF grouping variables) such as hearing impairment, race, and educational attainment. Previous analyses have not considered the effect of missing data on inferences, although levels of missing cognitive data can be substantial in epidemiologic studies. METHODS: We used data from Visit 6 (2016-2017) of the Atherosclerosis Risk in Communities Neurocognitive Study (N = 3,580) to explicate the effect of artificially imposed missing data patterns and imputation on DIF detection. RESULTS: When missing data was imposed among individuals in a specific DIF group but was unrelated to cognitive test performance, there was no systematic error. However, when missing data was related to cognitive test performance and DIF group membership, there was systematic error in DIF detection. Given this missing data pattern, the median DIF detection error associated with 10%, 30%, and 50% missingness was -0.03, -0.08, and -0.14 standard deviation (SD) units without imputation, but this decreased to -0.02, -0.04, and -0.08 SD units with multiple imputation. CONCLUSIONS: Incorrect inferences in DIF testing have downstream consequences for the use of cognitive tests in research. It is therefore crucial to consider the effect and reasons behind missing data when evaluating bias in cognitive testing.

Assessing Bias in Cognitive Testing for Older Adults with Sensory Impairment: An Analysis of Differential Item Functioning in the Baltimore Longitudinal Study on Aging (BLSA) and the Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS).

OBJECTIVES: Vision and hearing impairments affect 55% of people aged 60+ years and are associated with lower cognitive test performance; however, tests rely on vision, hearing, or both. We hypothesized that scores on tests that depend on vision or hearing are different among those with vision or hearing impairments, respectively, controlling for underlying cognition. METHODS: Leveraging cross-sectional data from the Baltimore Longitudinal Study of Aging (BLSA) and the Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS), we used item response theory to test for differential item functioning (DIF) by vision impairment (better eye presenting visual acuity worse than 20/40) and hearing impairment (better ear .5-4 kHz pure-tone average > 25 decibels). RESULTS: We identified DIF by vision impairment for tests whose administrations do not rely on vision [e.g., Delayed Word Recall both in ARIC-NCS: .50 logit difference between impaired and unimpaired (p = .04) and in BLSA: .62 logits (p = .02)] and DIF by hearing impairment for tests whose administrations do not rely on hearing [Digit Symbol Substitution test in BLSA: 1.25 logits (p = .001) and Incidental Learning test in ARIC-NCS: .35 logits (p = .001)]. However, no individuals had differences between unadjusted and DIF-adjusted measures of greater than the standard error of measurement. CONCLUSIONS: DIF by sensory impairment in cognitive tests was independent of administration characteristics, which could indicate that elevated cognitive load among persons with sensory impairment plays a larger role in test performance than previously acknowledged. While these results were unexpected, neither of these samples are nationally representative and each has unique selection factors; thus, replication is critical.

Clinical outcomes of gamma-irradiated sterile cornea in aqueous drainage device surgery: a multicenter retrospective study.

PurposeThe purpose of the study was to evaluate the safety and efficacy of gamma-irradiated sterile cornea (GISC) for covering the tube in aqueous drainage device (ADD) surgery in a retrospective, multicenter case series.Patients and methodsParticipants included 297 patients (321 procedures) who had undergone ADD surgery for the first time using GISC patch at three clinic centers in the United States between April 2009 and July 2012. The medical records of those consecutive patients were reviewed. Preoperative, intraoperative, and postoperative parameters about GISC were collected and analyzed. The main outcome measures were patch graft failure (PGF) and postoperative complications related to GISC.ResultsThree hundred and nineteen eyes in 295 patients were included in the current analysis. Ten out of the 319 eyes experienced PGF with a mean follow-up of 15.4±9.8 (SD) months. The overall cumulative PGF proportion from Kaplan-Meier analysis was 2.6% (95% CI: 0.6-4.7%) at 18 months. We detected two cases of presumed endophthalmitis related to PGF.ConclusionsGISC appears to have a reasonable success rate for preventing tube exposure related to PGF over an 18-month period. This success rate, in combination with other features of GISC (transparency and storage at room temperature), makes it a viable choice for patch graft material during ADD.

Nutrient composition and protein quality evaluation of eri silkworm (Samia ricinii) prepupae and pupae.

Eri silkworm (Samia ricinii) is a traditional source of food in northeast India, where it is grown primarily for silk and food uses. Nutrient analysis showed that the proximate composition of eri silkworm prepupae and pupae grown on either castor or tapioca were comparable and it was a good source of protein (16g%), fat (8g%) and minerals. The amino acid scores of eri prepupae and pupae protein were 99 and 100, respectively, with leucine as the limiting amino acid in both cases. Net protein utilisation (NPU) of prepupae and pupae was 41 as compared to 62 in casein. Protein digestibility corrected amino acid score (PDCAAS) was 86. The high protein content in the defatted eri silkworm meal (75%) with 44% total essential amino acids makes it an ideal candidate for preparing protein concentrate isolates with enhanced protein quality that can be used in animal nutrition.

Synthesis of new benzimidazole linked pyrrolo[2,1-c][1,4]benzodiazepine conjugates with efficient DNA-binding affinity and potent cytotoxicity.

The synthesis of new benzimidazole linked pyrrolobenzodiazepine conjugates is described. Some of these conjugates show significant DNA-binding affinity and, a representative compound 4c shows promising in vitro cytotoxicity against a number of human cancer cell lines.

Design, synthesis, and evaluation of mixed imine-amine pyrrolobenzodiazepine dimers with efficient DNA binding affinity and potent cytotoxicity.

Synthesis of mixed imine-amine pyrrolobenzodiazepine (PBD) dimers that are comprised of DC-81 and secondary amine (N10) of DC-81 subunits tethered to their C8 positions through alkanedioxy linkers (comprised of three and five carbons) is described. These noncross-linking unsymmetrical molecules exhibit significant DNA minor groove binding ability and one of them 5b linked through the pentanedioxy chain exhibits efficient DNA binding ability (DeltaTm=11.0 degrees C) when compared to naturally occurring DC-81, 1 (DeltaTm=0.7 degrees C). The imine-amine PBD dimers exhibit promising in vitro antitumor activity in a number of human cancer cell lines.

Synthesis of C8-linked pyrrolo[2,1-c][1,4]benzodiazepine-benzimidazole conjugates with remarkable DNA-binding affinity.

Two types of benzimidazoles have been synthesized and linked to DC-81 at C8-position through different alkyl chain spacers. These PBD conjugates have exhibited remarkable DNA-binding affinity, and a representative compound shows promising in vitro anticancer activity.

Synthesis and DNA binding affinity of novel A-C8/C-C2-exo unsaturated alkoxyamido-linked pyrrolo[2,1-c][1,4]benzodiazepine dimers.

The synthesis of novel A-C8/C-C2-exo unsaturated alkoxyamido-linked pyrrolo[2,1-c][1,4]benzodiazepine dimers is reported and these dimers show significant DNA binding affinity and they also exhibit moderate anticancer activity.

Synthesis of C8-linked pyrrolo[2,1-c][1,4]benzodiazepine-acridone/acridine hybrids as potential DNA-binding agents.

Pyrrolobenzodiazepine hybrids linked to acridone/acridine ring systems at C8-position have been designed and prepared that exhibit significant DNA-binding affinity, and a representative compound shows promising in vitro anticancer activity.

Synthesis and antitumour activity of pyrene-linked pyrrolo [2,1-c]benzodiazepine hybrids.

Pyrene-linked pyrrolobenzodiazepine hybrids have been synthesized that exhibit potential anticancer activity in a number of human tumour cell lines. These hybrids also exhibit much enhanced DNA-binding ability in comparison to the parent pyrrolobenzodiazepine ring system (DC-81).

Synthesis and DNA-binding affinity of A-C8/C-C2 alkoxyamido-linked pyrrolo[2,1-c][1,4]benzodiazepine dimers.

The synthesis of new A-C8/C-C2 alkoxyamido-linked pyrrolo[2,1-c][1,4]-benzodiazepine dimers have been described in this report. These dimers exhibit significant DNA-binding ability with moderate anticancer activity.

Design and synthesis of novel chrysene-linked pyrrolo[2,1-c][1,4]-benzodiazepine hybrids as potential DNA-binding agents.

Chrysene-linked pyrrolobenzodiazepine hybrids have been prepared that possess cytotoxicity in some cancer cell lines. They also exhibit promising DNA-binding affinity and this is supported by molecular modeling studies.

Synthesis of C-8 methanesulphonate substituted pyrrolobenzodiazepines as potential antitumour agents.

The facile synthesis of C-8 methanesulphonate substituted pyrrolobenzodiazepines is described. These have been prepared by linking the methanesulphonate at C-8 position with alkanol spacer and their in vitro cytotoxicity have been described.

Synthesis of novel C2 and C2-C8 linked pyrrolo[2,1-c][1,4]benzodiazepine-naphthalimide hybrids as DNA-binding agents.

Synthesis of C2 and C2-C8 linked pyrrolobenzodiazepine-naphthalimide hybrids have been prepared that exhibit significant DNA-binding affinity and cytotoxicity.

Design, synthesis, and evaluation of new noncross-linking pyrrolobenzodiazepine dimers with efficient DNA binding ability and potent antitumor activity.

New sequence selective mixed imine-amide pyrrolobenzodiazepine (PBD) dimers have been developed that are comprised of DC-81 and dilactam of DC-81 subunits tethered to their C8 positions through alkanedioxy linkers (comprised of three to five and eight carbons). Thermal denaturation studies show that after 18 h of incubation with calf thymus DNA at a 5:1 DNA/ligand ratio, one of them (5c) increases the DeltaT(m) value by 17.0 degrees C. Therefore, these unsymmetrical molecules exhibit significant DNA minor groove binding affinity and 5c linked through the pentanedioxy chain exhibits efficient DNA binding ability that compares with the cross-linking DSB-120 PBD dimer (DeltaT(m) = 15.4 degrees C). Interestingly, this imine-amide PBD dimer has been linked with a five carbon chain linker unlike DSB-120, which has two DC-81 subunits with a three carbon chain linker, illustrating the effect of the noncross-linking aspect by introducing the noncovalent subunit. The binding affinity of the compounds has been measured by restriction endonuclease digestion assay based on inhibition of the restriction endonuclease BamHI. This study reveals the significance of noncovalent interactions in combination with covalent bonding aspects when two moieties of structural similarities are joined together. This allows the mixed imine-amide PBD dimer with a five carbon chain linker to achieve an isohelical fit within the DNA minor groove taking in to account both the covalent bonding and the noncovalent binding components. This has been supported by molecular modeling studies, which indicate that the PBD dimer with a five carbon chain linker gives rise to maximum stabilization of the complex with DNA at the minor groove as compared to the other PBD dimers with three, four, and eight carbon chain linkers. The energy of interaction in all of the complexes studied is correlated to the DeltaT(m) values. Furthermore, this dimer 5c has significant cytotoxicity in a number of human cancer cell lines.

Synthesis of C-8 alkylamino substituted pyrrolo[2,1-c][1,4]benzodiazepines as potential anti-cancer agents.

The design and facile synthesis of C-8 alkylamino substituted pyrrolo[2,1-c][1,4]benzodiazepines is described. These have been prepared by linking the amines at C-8 position with propane spacer to improve solubility in water, and their in vitro cytotoxicity studies have been carried out.

Normal light response, photoreceptor integrity, and rhodopsin dephosphorylation in mice lacking both protein phosphatases with EF hands (PPEF-1 and PPEF-2).

Rhodopsin dephosphorylation in Drosophila is a calcium-dependent process that appears to be catalyzed by the protein product of the rdgC gene. Two vertebrate rdgC homologs, PPEF-1 and PPEF-2, have been identified. PPEF-1 transcripts are present at low levels in the retina, while PPEF-2 transcripts and PPEF-2 protein are abundant in photoreceptors. To determine if PPEF-2 alone or in combination with PPEF-1 plays a role in rhodopsin dephosphorylation and to determine if retinal degeneration accompanies mutation of PPEF-1 and/or PPEF-2, we have produced mice carrying targeted disruptions in the PPEF-1 and PPEF-2 genes. Loss of either or both PPEFs has little or no effect on rod function, as mice lacking both PPEF-1 and PPEF-2 show little or no changes in the electroretinogram and PPEF-2-/- mice show normal single-cell responses to light in suction pipette recordings. Light-dependent rhodopsin phosphorylation and dephosphorylation are also normal or nearly normal as determined by (i) immunostaining of PPEF-2-/- retinas with the phosphorhodopsin-specific antibody RT-97 and (ii) mass spectrometry of C-terminal rhodopsin peptides from mice lacking both PPEF-1 and PPEF-2. Finally, PPEF-2-/- retinas show normal histology at 1 year of age, and retinas from mice lacking both PPEF-1 and PPEF-2 show normal histology at 3 months of age, the latest time examined. These data indicate that, in contrast to loss of rdgC function in Drosophila, elimination of PPEF function does not cause retinal degeneration in vertebrates.