Performance of doweled concrete joints subjected to fatigue loading

Distress in concrete transverse joints is often initiated due to the development of excessive stresses at the dowel/concrete interface. Recent studies indicated the existence of two types of stresses i.e. compressive stresses at the top and bottom of the dowel and tensile stresses at both sides of the dowel bar. These stresses are the primary concern as they are believed to be a major factor for the failure of rigid pavement joints.;Dr. Shoukry invented a new dowel design named shokbar that significantly reduces the magnitude of such contact stresses. The primary objective of this study is to characterize the behavior of shokbars versus regular dowels. Simulated rigid pavements joints were used for an experimental and finite element study where both devices were subjected to static and fatigue loading. (Abstract shortened by UMI.)

Harjumaa põimevaipade kompositsioonilised tüübid 19. sajandil – 20. sajandi 30-ndatel aastatel. Koopiavaip Eesti Vabaõhumuusemile

Karin Vetsa töös on uuritud ajaloolisel Harjumaal 19. sajandil ja 20. sajandi alguskümnenditel levinud põimevaipade kompositsioonilisi tüüpe. Vaatluse alla on võetud 221 Eesti muuseumitest ja erakogudest leitud naast- ja pindpõime ning nendega kombineeritud tehnikates vaipa. Uurimustöö keskse probleemina on püütud välja selgitada olemasolevaid seoseid vaipade kompositisooniliste tüüpide ja kihelkondliku päritolu vahel. Kaardistatud vaibad jaotusid kahte suuremasse rühma: piiramata ja piiratud pinnajaotusega vaibatüübid. Piiramata pinnaga vaibarühma liigitusid triibustiku- ja ruudustiku-põhised vaibad. Piiratud e suletud pinnajaotusega vaibarühm jagunes ühtlase keskväljakuga ja kontsentrilise kompositsiooniga allrühmaks. Töö tulemusena selgus, et ilmnesid piirkondlikud eripärad vaipade kompositsioonitüüpides – neid eripärasid on töös ka tutvustatud. Praktilise tööna teostati vaibakomplekt, mis koosnes Eesti Rahva Muuseumis leiduva Nissi kihelkonna pindpõimevaiba eeskujul valmistatud koopiast Eesti Vabaõhumuuseumile ja samas koloriidis lihttriibulisest vaibast tänapäevasesse interjööri. Töös kirjeldatakse telgedel kootud vaibakomplekti valmistamiskäiku, antakse ülevaade aja- ja materjalikulust

Regional Gray Matter Growth, Sexual Dimorphism, and Cerebral Asymmetry in the Neonatal Brain

Although there has been recent interest in the study of childhood and adolescent brain development, very little is known about normal brain development in the first few months of life. In older children, there are regional differences in cortical gray matter development, whereas cortical gray and white matter growth after birth has not been studied to a great extent. The adult human brain is also characterized by cerebral asymmetries and sexual dimorphisms, although very little is known about how these asymmetries and dimorphisms develop. We used magnetic resonance imaging and an automatic segmentation methodology to study brain structure in 74 neonates in the first few weeks after birth. We found robust cortical gray matter growth compared with white matter growth, with occipital regions growing much faster than prefrontal regions. Sexual dimorphism is present at birth, with males having larger total brain cortical gray and white matter volumes than females. In contrast to adults and older children, the left hemisphere is larger than the right hemisphere, and the normal pattern of fronto-occipital asymmetry described in older children and adults is not present. Regional differences in cortical gray matter growth are likely related to differential maturation of sensory and motor systems compared with prefrontal executive function after birth. These findings also indicate that whereas some adult patterns of sexual dimorphism and cerebral asymmetries are present at birth, others develop after birth

Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

Festivali Jazzkaar 2023 tasuta kontsertide päev

https://www.ester.ee/record=b5562307*es