396 research outputs found

    MAT-708: MONITORING THE CORROSION PROCESS OF REINFORCED CONCRETE FLAT SLAB-COLUMN CONNECTION

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    The corrosion of the steel reinforcement embedded in a two-way reinforced concrete flat slab around the column stub area was investigated in this study, which aimed to studying the effect of corrosion on the shear punching behavior. Two square flat slab-column connections were cast, the flat slab dimension was 1900 mm × 1900 mm × 150 mm, and the column dimensions was 250 mm × 250 mm. A specific delaminated area was corroded around the column stub to emphasize the effect of corrosion around punching area. The corrosion reached two levels of mass loss uniformly over that specified area: 0% and 26%. Corrosion process was monitored under an accelerated corrosion technique through the application of a constant potential of fifteen volts to reach the targeted uniform corrosion level. Then, the corrode slab-column connection was loaded until failure for each slab occurred. The corrosion performance of the slab was evaluated based on the results of the current measurement, half-cell potential tests, and mass loss. The test results show that the corrosion of reinforcement rebar around the column stub in flat slab causes a significant loss in punching shear capacity and affects the structural integrity by increasing crack widths

    Structure of the Deformed 7075 Aircraft Al - Alloy with Material Analysis Using Diffraction (MAUD)

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    This work aims to study the effect of plastic deformation on the 7075 Al - alloy using Material Analyses Using Diffraction (MAUD). Plastic deformation produces dislocation defects. Using a hydraulic press, samples were deformed up to 25%. The XRD was measured for each degree of deformation. The MAUD program was used to analyze the data, and mathematical methods were deployed to understand the various behaviors observed. The lattice parameter, crystallite size, average internal stress, micro-strain, and dislocation density of the 7075Al-alloy were calculated. As the deformation degree increased, there was a progressive decline in the crystallite size as an increase in the micro-strain and dislocation density. The flow stress changes from 5.8 to 49 MPa and the stored dislocation energy varies from 2.62 to 185 kPa

    Building artificial neural circuits for domain-general cognition: a primer on brain-inspired systems-level architecture

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    There is a concerted effort to build domain-general artificial intelligence in the form of universal neural network models with sufficient computational flexibility to solve a wide variety of cognitive tasks but without requiring fine-tuning on individual problem spaces and domains. To do this, models need appropriate priors and inductive biases, such that trained models can generalise to out-of-distribution examples and new problem sets. Here we provide an overview of the hallmarks endowing biological neural networks with the functionality needed for flexible cognition, in order to establish which features might also be important to achieve similar functionality in artificial systems. We specifically discuss the role of system-level distribution of network communication and recurrence, in addition to the role of short-term topological changes for efficient local computation. As machine learning models become more complex, these principles may provide valuable directions in an otherwise vast space of possible architectures. In addition, testing these inductive biases within artificial systems may help us to understand the biological principles underlying domain-general cognition.Comment: This manuscript is part of the AAAI 2023 Spring Symposium on the Evaluation and Design of Generalist Systems (EDGeS

    Diagnostic, regenerative or fossil-free- exploring stakeholder perceptions of Swedish food system sustainability

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    In an analysis of food system sustainability challenges and solutions among Swedish food system actors using Q -methodology, five perspectives were identified. One of the main three perspectives placed the highest priority on reduced meat consumption, food waste, and climate impact in agriculture, but downplayed strategies highlighted in the national food strategy and social aspects, and can be interpreted as a diagnostic climate mitigation-oriented perspective that does not reflect current negotiated policy processes or 'softer' values of food. In an alternative regenerative perspective, industrialized large-scale farming and lack of internalization of external costs were regarded as the main problems, and diversity, soil health, and organic farming as the main solutions. Proponents of a third perspective regarded phasing out fossil fuels, increased profitability of companies, increased meat production, and self-sufficiency as high priorities. These contrasting views can be a major barrier to transforming the Swedish food system. However, a number of entry points for change (i.e. aspects highly important for some and neutral for others) were identified, including focusing on healthy diets and increased production of fruit and vegetables. Focusing on these can build trust among stakeholders before moving to discussions about the larger and more sensitive systemic changes needed

    Mycotoxin Adducts on Human Serum Albumin: Biomarkers of Exposure to Stachybotrys chartarum

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    OBJECTIVE: Despite the growing body of evidence showing adverse health effects from inhalation exposure to the trichothecene-producing mold Stachybotrys chartarum, controversy remains. Currently, there are no reliable assays suitable for clinical diagnosis of exposure. We hypothesized that satratoxin G (SG)–albumin adducts may serve as biomarkers of exposure to this fungus. DESIGN: We studied the formation of adducts of SG with serum albumin in vitro using Western blots and mass spectrometry (MS) and searched for similar adducts formed in vivo using human and animal serum. RESULTS: Samples of purified human serum albumin that had been incubated with increasing concentrations of SG showed concentration-dependent albumin bands in Western blots developed with anti-SG antibodies. MS analysis found that as many as 10 toxin molecules can be bound in vitro to one albumin molecule. The sequencing of albumin-adduct tryptic peptides and the analysis of pronase/aminopeptidase digests demonstrated that lysyl, cysteinyl, and histidyl residues are involved in the formation of these adducts. Serum samples from three patients with documented exposure to S. chartarum similarly revealed lysine–, cysteine–, and histidine–SG adducts after exhaustive digestion, affinity column enrichment, and MS analysis. These adducts were also found in the sera from rats exposed to the spores of S. chartarum in contrast to control human subjects and control animals. CONCLUSIONS: These data document the occurrence of SG–albumin adducts in both in vitro experiments and in vivo human and animal exposures to S. chartarum. RELEVANCE TO CLINICAL PRACTICE: SG–amino acid adducts may serve as reliable dosimeter biomarkers for detection of exposure to S. chartarum

    Food Technology Research Institute, Agricultural Research Center, Giza, Egypt

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    Day by day increase the importance of using the natural food additives. Hence in this study, the phenolic extracted from basil leaves, spearmint leaves and fennel seeds, as natural antioxidants, were added at concentrations 200, 400 and 600 ppm from fat weight using in biscuit production. Biscuit was stored at room temperature for 8 months. Induction period was measured by Rancimat apparatus. Total phenolic and phenolic acids were determined. Peroxide value, acid value, thiobarbituric acid and refractive index were measured during storage. Antimicrobial activity of phenolic extraction were examined after 8 months. Sensory evaluation was measured directly after baking. The results showed that total phenolic content in basil leaves, spearmint leaves and fen-nel seeds were 3.97, 1.91 and 1.53 mg/g as caffeic acid equivalents respectively. Five phenolic acids were found in both basil leaves and spearmint leaves, while four phenolic acids were found in fennel seeds as determined by using HPLC. Rancimat results showed that induction period for phenolic herbs could be ranked as follow: basil leaves > spearmint leaves > fennel seeds. The re-sults elucidated that the best concentration from natural additives as antioxidants activity were 400 and 600 ppm compared with BHT. The results revealed that with increasing the concentration of natural antioxidants increased, the more peroxide value, acid value, thiobarbituric acid and refractive index were decreased. Total bacterial count and (yeast & mold) count were decreased with increas-ing the concentration phenolic additives. Sensory evaluation indicated that addition of different anti-oxidants showed no significant differences be-tween control and biscuit sample

    Effect of Progesterone Therapy versus Diet Modification on Constipation during Pregnancy

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    Background: Pregnant women may experience constipation for the first time or their existing constipation symptoms increase in severity during pregnancy.Aim: To compare the effect of progesterone versus diet modification in the treatment of constipation during pregnancy.Subjects and Methods: Women aged ≥18 years with functional constipation according to the Rome III criteria from obstetrics outpatients’ clinic and midwife practices included in this study. Participants divided into two groups; control group managed with diet modifications and study group pregnant women with threatened miscarriage and advised to take vaginal progesterone ≥1 week. Participants completed a nonvalidated questionnaire created by the authors during the whole week before intake of progesterone or diet modifications and after treatment phase. Independent Student’s t‑test and Chi‑square (X2) test were used for statistical analysis to compare between two studied groups. Primary outcome measures; change in defecation frequency.Results: Sensation of anorectal obstruction and sensation of incomplete evacuation were significantly less in Group B (progesterone therapy) compared to Group A (diet modification) (54% [154/281] and 62.98% [177/281] vs. 89.76% [614/684] and 91.08% [623/684], respectively) (P = 0.04 and 0.03, respectively). Straining during defecation and manual maneuvers to facilitate evacuation were significantly less in Group B compared to Group A (63.7% [179/281] and 19.9% [56/281] vs. 94.59% [647/684] and 86.54% [592/684], respectively) (P < 0.01 and 0.02, respectively). Episodes of abdominal pain and presence of reflux episodes were also significantly less in Group B compared to Group A (18.5% [52/281] and 17.43% [49/281] vs. 84.11% [589/684] and 75% [513/684], respectively) (P = 0.01 and 0.03, respectively). Conclusions: Estrogen, rather than progesterone, may be a detrimental factor of constipation during pregnancy via decreased bowel movement. Progesterone therapy seems to be effective in the treatment of functional constipation during pregnancy. A randomized placebo controlled trial is required to confirm the data of this study.KEY WORDS: Constipation, diet modification, pregnancy, progesteron

    A non-randomised controlled study to assess the effectiveness of a new proactive multidisciplinary care intervention for older people living with frailty

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    BackgroundIntegrated care may improve outcomes for older people living with frailty. We aimed to assess the effectiveness of a new, anticipatory, multidisciplinary care service in improving the wellbeing and quality of life (QoL) of older people living with severe frailty.MethodsA community-based non-randomised controlled study. Participants (≥65 years, electronic Frailty Index ≥0.36) received either the new integrated care service plus usual care, or usual care alone. Data collection was at three time points: baseline, 2-4 weeks, and 10-14 weeks. The primary outcome was patient wellbeing (symptoms and other concerns) at 2-4 weeks, measured using the Integrated Palliative care Outcome Scale (IPOS); the secondary outcome was QoL, measured using EQ-5D-5L. To test duration of effect and safety, wellbeing and QoL were also measured at 10-14 weeks. Descriptive statistics were used to characterise and compare intervention and control groups (eligible but had not accessed the new service), with t-test, Chi-Square, or Mann-Whitney U tests (as appropriate) to test differences at each time point. Generalised linear modelling, with propensity score matching, was used for further group comparisons. Data were analysed using STATA v17.Results199 intervention and 54 control participants were recruited. At baseline, intervention and control groups were similar in age, gender, ethnicity, living status, and body mass index, but not functional status or area deprivation score. At 2-4 weeks, wellbeing had improved in the intervention group but worsened in the control (median IPOS -5 versus 2, p<0.001). QoL improved in the intervention group but was unchanged in the control (median EQ-5D-5L 0.12, versus 0.00, p<0.001). After adjusting for age, gender, and living status, the intervention group had an average total IPOS score reduction at 2-4 weeks of 6.34 (95% CI: -9.01: -4.26, p<0.05); this improvement was sustained, with an average total IPOS score reduction at 10-14 weeks of 6.36 (95% CI: -8.91:-3.80, p<0.05). After propensity score matching based on functional status/area deprivation, modelling showed similar results, with a reduction in IPOS score at 2-4 weeks in the intervention group of 7.88 (95% CI: -12.80: -2.96, p<0.001).ConclusionsOur findings suggest that the new, anticipatory, multidisciplinary care service may have improved the overall wellbeing and quality of life of older people living with frailty at 2-4 weeks and the improvement in wellbeing was sustained at three months

    Split or Steal? Cooperative Behavior When the Stakes Are Large

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    We examine cooperative behavior when large sums of money are at stake, using data from the television game show Golden Balls. At the end of each episode, contestants play a variant on the classic prisoner's dilemma for large and widely ranging stakes averaging over $20,000. Cooperation is surprisingly high for amounts that would normally be considered consequential but look tiny in their current context, what we call a “big peanuts” phenomenon. Utilizing the prior interaction among contestants, we find evidence that people have reciprocal preferences. Surprisingly, there is little support for conditional cooperation in our sample. That is, players do not seem to be more likely to cooperate if their opponent might be expected to cooperate. Further, we replicate earlier findings that males are less cooperative than females, but this gender effect reverses for older contestants because men become increasingly cooperative as their age increases
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