Detection of Internal Defects in Concrete Members Using Global Vibration Characteristics

Rock-pocket and honeycomb defects impair overall stiffness, accelerate aging, reduce service life, and cause structural problems in hardened concrete members. Traditional methods for detecting such deficient volumes involve visual observations or localized nondestructive methods, which are labor-intensive, time-consuming, highly sensitive to test conditions, and require knowledge of and accessibility to defect locations. The authors propose a vibration response-based nondestructive technique that combines experimental and numerical methodologies for use in identifying the location and severity of internal defects of concrete members. The experimental component entails collecting mode shape curvatures from laboratory beam specimens with size-controlled rock pocket and honeycomb defects, and the numerical component entails simulating beam vibration response through a finite element (FE) model parameterized with three defect-identifying variables indicating location (x, coordinate along the beam length) and severity of damage (alpha, stiffness reduction and beta, mass reduction). Defects are detected by comparing the FE model predictions to experimental measurements and inferring the low number of defect-identifying variables. This method is particularly well-suited for rapid and cost-effective quality assurance for precast concrete members and for inspecting concrete members with simple geometric forms.

Position paper on the management of patients with obstructive sleep apnea and hypertension: joint recommendations by the European Society of Hypertension, by the European Respiratory Society and by the members of European COST (COoperation in Scientific and Technological research) ACTION B26 on obstructive sleep apnea

This article is aimed at addressing the current state of the art in epidemiology, pathophysiology, diagnostic procedures and treatment options for appropriate management of obstructive sleep apnea (OSA) in cardiovascular (particularly hypertensive) patients, as well as for the management of cardiovascular diseases (particularly arterial hypertension) in OSA patients. The present document is the result of the work done by a panel of experts participating in the European Union COST (COoperation in Scientific and Technological research) ACTION B26 on OSA, with the endorsement of the European Respiratory Society (ERS) and the European Society of Hypertension (ESH). These recommendations are particularly aimed at reminding cardiovascular experts to consider the occurrence of sleep-related breathing disorders in patients with high blood pressure. They are at the same time aimed at reminding respiration experts to consider the occurrence of hypertension in patients with respiratory problems at night.

Proposal of Bisgaardia hudsonensis gen. nov., sp. nov. and an additional genomospecies, isolated from seals, as new members of the family Pasteurellaceae

Phenotypic and phylogenetic studies were performed on eight Gram-negative-staining, rod-shaped bacteria isolated from seals. Biochemical and physiological studies showed identical profiles for all of the isolates and indicated that they were related to the family Pasteurellaceae. 16S rRNA gene sequencing demonstrated that the organism represented a distinct cluster with two sublines within the family Pasteurellaceae with <96% sequence similarity to any recognized species. Multilocus sequence analysis (MLSA) including rpoB, infB and recN genes further confirmed these findings with the eight isolates forming a genus-like cluster with two branches. Genome relatedness as deduced from recN gene sequences suggested that the isolates represented a new genus with two species. On the basis of the results of the phylogenetic analysis and phenotypic criteria, it is proposed that these bacteria from seals are classified as Bisgaardia hudsonensis gen. nov., sp. nov. (the type species) and Bisgaardia genomospecies 1. The G+C content of the DNA was 39.5 mol%. The type strain of Bisgaardia hudsonensis gen. nov., sp. nov. is M327/99/2(T) (=CCUG 43067(T)=NCTC 13475(T)=98-D-690B(T)) and the reference strain of Bisgaardia genomospecies 1 is M1765/96/5 (=CCUG 59551=NCTC 13474).

Effective Length K-Factors For Flexural Buckling Strengths Of Web Members In Open Web Steel Joists

Open web steel joists are designed in the United States following the governing specification published by the Steel Joist Institute. For compression members in joists, this specification employs an effective length factor, or K-factor, in confirming their adequacy. In most cases, these K-factors have been conservatively assumed equal to 1.0 for compression web members, regardless of the fact that intuition and limited experimental work indicate that smaller values could be justified. Given that smaller K-factors could result in more economical designs without a loss in safety, the research presented in this thesis aims to suggest procedures for obtaining more rational values. Three different methods for computing in-plane and out-of-plane K-factors are investigated, including (1) a hand calculation method based on the use of alignment charts, (2) computational critical load (eigenvalue) analyses using uniformly distributed loads, and (3) computational analyses using a compressive strain approach. The latter method is novel and allows for computing the individual buckling load of a specific member within a system, such as a joist. Four different joist configurations are investigated, including an 18K3, 28K10, and two variations of a 32LH06. Based on these methods and the very limited number of joists studied, it appears promising that in-plane and out-of-plane K-factors of 0.75 and 0.85, respectively, could be used in computing the flexural buckling strength of web members in routine steel joist design. Recommendations for future work, which include systematically investigating a wider range of joist configurations and connection restraint, are provided.

Fabry's disease: otoneurologic findings in twelve members of one family

Fabry's disease corresponds to an inherited disorder transmitted by an X-linked recessive gene. It generates a dysfunction of glycosphingolipid metabolism due to an enzymatic deficiency of alpha-galactosidase activity, resulting in glycosphingolipid deposits in all areas of the body. The clinical (heart, kidney, and central nervous system) manifestations are more severe in hemizygous boys than in heterozygous girls. They appear during childhood or adolescence: acroparesthesia, joint pain, angiokeratoma, corneal dystrophy, hypohydrosis or anhydrosis, and renal failure. The otoneurologic symptoms consist of hearing fluctuation, progressive unilateral or bilateral hearing loss, and episodes of vertigo or dizziness. Otoneurologic findings in 12 of 26 members of the same family are presented: the mother and 9 of her 12 children, as well as 2 of her 14 grandchildren: 4 healthy persons, 4 heterozygous female carriers, and 4 hemizygous male patients. Three of the male patients had fluctuation of hearing, sudden hearing loss, and episodes of vertigo and dizziness. The otoneurologic examinations showed a bilateral cochleovestibular deficit (n = 1), a right cochleovestibular deficit (n = 1), and a bilateral hearing loss combined with a right vestibular deficit (n = 1). Histopathologic evidence of glycosphingolipid accumulation in vascular endothelial and ganglion cells, as well as atrophy of the stria and spiral ligament, might explain the otoneurologic symptoms and findings.

[Experiences of patients and family members during the stay on a nursing unit]

In 2004, the university hospital of Berne ran a pilot project with a Nursing Unit (NU). In this unit patients who no longer needed a close surveillance by physicians were cared for. They needed primarily complex professional nursing care which could not be provided by other hospitals, nursing homes, home care or family members. The nurses were responsible for the coordination of care. This qualitative study investigated experiences of patients and family members with the care concept of the NU. Thematically focused interviews were conducted with nine patients and five family members. Qualitative content analysis was used for data analysis. Results show that patients and family members mostly accepted the new care concept. They positively experienced the quiet and restful atmosphere, the patient-centred and continuous care by competent nurses, the education and the discharge planning. Some study participants reported missing information at the time of their transfer to the NU, insufficient assessments or unsuitable educational scripts. The study provides evidence to positive effects of a patient-centred care approach.

PHYLOGENETIC ANALYSES, GENE DOSAGE EFFECT AND SELECTION IN MEMBERS OF THE LATERAL BOUNDARY DOMAIN (LBD) GENES TRANSCRIPTION FACTOR FAMILY

Wood formation is an economically and environmentally important process and has played a significant role in the evolution of terrestrial plants. Despite its significance, the molecular underpinnings of the process are still poorly understood. We have previously shown that four Lateral Boundary Domain (LBD) transcription factors have important roles in the regulation of wood formation with two (LBD1 and LBD4) involved in secondary phloem and ray cell development and two (LBD15 and LBD18) in secondary xylem formation. Here, we used comparative phylogenetic analyses to test potential roles of the four LBD genes in the evolution of woodiness. We studied the copy number and variation in DNA and amino acid sequences of the four LBDs in a wide range of woody and herbaceous plant taxa with fully sequenced and annotated genomes. LBD1 showed the highest gene copy number across the studied species, and LBD1 gene copy number was strongly and significantly correlated with the level of ray seriation. The lianas, cucumber and grape, with multiseriate ray cells showed the highest gene copy number (12 and 11, respectively). Because lianas’ growth habit requires significant twisting and bending, the less lignified ray parenchyma cells likely facilitate stem flexibility and maintenance of xylem conductivity. We further demonstrate conservation of amino acids in the LBD18 protein sequences that are specific to woody taxa. Neutrality tests showed evidence for strong purifying selection on these gene regions across various orders, indicating adaptive convergent evolution of LBD18. Structural modeling demonstrates that the conserved amino acids have a significant impact on the tertiary protein structure and thus are likely of significant functional importance.

Three members of the connective tissue growth factor family CCN are differentially regulated by mechanical stress

Expression of connective tissue growth factor (CTGF), a member of the CCN gene family, is known to be significantly induced by mechanical stress. We have therefore investigated whether other members of the CCN gene family, including Cyr61 and Nov, might reveal a similar stress-dependent regulation. Fibroblasts growing under stressed conditions within a three-dimensional collagen gel showed at least a 15 times higher level of Cyr61 mRNA than cells growing under relaxed conditions. Upon relaxation, the decline of the Cyr61 mRNA to a lower level occurred within 2 h, and was thus quicker than the response of CTGF. The regulation was fully reversible when stress was reapplied. Thus, Cyr61 represents another typical example of a stress-responsive gene. The level of the Nov mRNA was low in the stressed state, but increased in the relaxed state. This CCN gene therefore shows an inverted regulation relative to that of Cyr61 and CTGF. Inhibition of protein kinases by means of staurosporine suppressed the stress-induced expression of Cyr61 and CTGF. Elevated levels of cAMP induced by forskolin mimicked the effects of relaxation on the regulation of Cyr61, CTGF and Nov. Thus, adenylate cyclase as well as one or several protein kinases might be involved in the mechanoregulation of these CCN genes.