A note on "A LP-based heuristic for a time-constrained routing problem"

In their paper, Avella et al. (2006) investigate a time-constrained routing problem. The core of the proposed solution approach is a large-scale linear program that grows both row- and column-wise when new variables are introduced. Thus, a column-and-row generation algorithm is proposed to solve this linear program optimally, and an optimality condition is presented to terminate the column-and-row generation algorithm. We demonstrate by using Lagrangian duality that this optimality condition is incorrect and may lead to a suboptimal solution at termination

A note on "A LP-based heuristic for a time-constrained routing problem"

Avella et al. (2006) [Avella, P., D'Auria, B., Salerno, S. (2006). A LP-based heuristic for a time-constrained routing problem. European Journal of Operational Research 173:120-124] investigate a time-constrained routing (TCR) problem. The core of the proposed solution approach is a large-scale linear program (LP) that grows both row- and column-wise when new variables are introduced. Thus, a column-and-row generation algorithm is proposed to solve this LP optimally, and an optimality condition is presented to terminate the column-and-row generation algorithm. We demonstrate that this optimality condition is incorrect and may lead to a suboptimal solution at termination. We identify the source of this error and discuss how the generic column-and-row generation algorithm proposed by Muter et al. (2010) may be applied to this TCR problem in order to solve the proposed large-scale LP correctly

Outcomes and effectiveness of bilateral percutaneous transluminal renal artery stenting in patients with critical bilateral renal artery stenosis

Background: The aim of this study was to assess the effects of percutaneous bilateral renal artery stenting in patients with atherosclerotic renal artery stenosis and in-hospital and 4 month outcome of the procedure, focusing on the changes in renal function and blood pressure. Methods: Five consecutive patients (mean age: 64.8 ± 9.7 years, 1 women) with bilateral renal artery stenoses underwent percutaneous interventions. We compared blood pressure, number of oral antihypertensive medications, and renal function changes preprocedure and postprocedure at 4 months follow-up. Results: A total of 5 bilateral atherosclerotic renal artery stenosis patients underwent percutaneous transluminal renal angioplasty and 10 stents were placed. Although systolic and diastolic blood pressures were significantly decreased in follow-up period, glomerular filtration rates were not significantly changed as compared with baseline data (p = 0.009, p = 0.008, p = 1.00, respectively). Also, the number of oral antihypertensive medications were significantly decreased at follow-up period (p = 0.03). Conclusions: Bilateral renal artery stenting provides a beneficial outcome such as stabilization of renal functions, significant improvement in blood pressure control and reduction in the number of oral antihypertensive medications at follow-up

Zmiany stężeń hormonów tarczycy u pacjentów z rozpoznaniem śmierci mózgu mają związek z non-thyroidal illness syndrome

Introduction: Alterations in thyroid hormone levels occur in patients with acute neurological disease states. The aim of this study is to study changes in thyroid hormones in patients with brain death (BD). Material and methods: Eleven brain-dead patients were studied prospectively. Thyroid hormones were measured on admission to the intensive care unit, the day before BD diagnosis (BD before), and the day after BD diagnosis (BD day). Results: Thyroid stimulating hormone (TSH) and free triiodothyronine (fT3) concentrations were found to be significantly low on ad­mission, BD before, and BD day compared to age-matched healthy controls. TSH levels were shown to be increasing on BD day. Free thyroxine (fT4) levels were within normal limits in all cases except in one case having low fT4 levels with normal TSH levels. No statisti­cally significant changes were encountered between admission thyroid hormone levels and BD-before and BD-day thyroid hormone levels. Six patients were on steroid therapy when BD-before blood samples were drawn, and no difference in thyroid hormone levels was encountered between steroid users and non-users. Correlation analysis showed a positive correlation between GCS and TSH, but a negative association between fT3 and APACHE II. Conclusion: We have shown that patients with BD have altered thyroid hormones days before BD diagnosis, and these alterations con­tinue until the diagnosis of BD. The changes in thyroid hormones are compatible with non-thyroidal illness syndrome

Utfordringer og muligheter med implementering av BIM ved bruk av Lean Construction, der det settes søkelys på byggebransjens videre teknologiske utvikling.

Byggebransjen blir stort sett kritisert for å være ineffektiv, og har derfor også stort forbedringspotensial når det gjelder kostnadseffektivitet, produktivitet, gjennomføringsevne og sløsing. Dette er bemerkelsesverdig spesielt når man sammenlikner byggebransjen med andre bransjer. Derfor har bransjen som en reaksjon til disse problemene kommet med ulike initiativer med mål om en utvikling og forandring. Som følge av dette har nyere teknologi, verktøy og metoder blitt fremmet, og som har ledet til et paradigmeskifte for måten et byggeprosjekt prosjekteres og gjennomføres. Gjennomgående funn i litteratur peker på manglende basiskunnskaper om Lean-filosofien, manglende kompetanse innen BIM, motstand mot endring i byggebransjen, samt for lite vektlegging på kontinuerlige forbedring og inkludering av alle aktører i leveringskjeden. Det er blitt benyttet både kvalitative og kvantitative metoder til informasjonshenting. Der teoridelen ble tilegnet ved dokumentgjennomgang, ble den empiriske dataen tilegnet ved spørreundersøkelse, gjennomføring av dybdeintervjuer og en dokumentanalyse med etterfølgende casestudie av KHiB-prosjektet. Forskningsstudiet avdekker et bredt spekter av funn, hvor noen aspekter fremstår som sentrale både i empirien og i litteraturen, men også noen forskjeller finnes det her. Dette vil bli vist nærmere i Kapittel 6, der empiriske dataen settes opp mot litteraturfunn. Videre vil det i Kapittel 7 diskuteres rundt forskningsspørsmålene som blir stilt for å prøve å svare på problemstillingen til masteroppgaven: Utfordringer og muligheter med implementering av BIM ved bruk av Lean Construction, der det settes søkelys på byggebransjens videre teknologiske utvikling, og avslutningsvis vil det bli en konklusjon og en anbefaling til videre arbeid i Kapittel 8.The construction industry is largely criticized for being inefficient, and therefore has great potential for improvement in terms of cost efficiency, productivity, feasibility and waste. This is remarkable especially when one compares the construction industry with other industries. Therefore, in response to these problems, the industry has come up with various initiatives with the goal of development and change. As a result, newer technology, tools and methods have been promoted, which have led to a paradigm shift in the way a construction project is designed and implemented. Consistent findings in the literature point to a lack of basic knowledge about Lean philosophy, a lack of competence in BIM, resistance to change in the construction industry, as well as too little emphasis on continuous improvement and inclusion of all players in the supply chain. Both qualitative and quantitative methods of information retrieval have been used. Where the theory part was acquired by document review, the empirical data was acquired by questionnaire, conducting in-depth interviews and a document analysis with subsequent case study of the KHiB project. The research study reveals a wide range of findings, where some aspects appear to be central both in the empirical and in the literature, but there are also some differences here. This will be shown in more detail in Chapter 6, where the empirical data is set up against literature findings. Furthermore, Chapter 7 will discuss the research questions that are asked to answer the problem of the master's thesis: Challenges and opportunities with implementation of BIM using Lean Construction, where the focus will be on the construction industry's further technological development, and finally there will be a conclusion and a recommendation for further work in Chapter

Lycopene Prevents Development of Steatohepatitis in Experimental Nonalcoholic Steatohepatitis Model Induced by High-Fat Diet

We investigated the preventive effect of lycopene on nonalcoholic steatohepatitis-induced by high-fat diet in rats. Forty male Sprague-Dawley rats were divided into 4 groups. They were fed standard diet, high-fat diet (HFD), high-fat diet plus lycopene at a dose of 2 mg/kg body weight and the high-fat diet lycopene at a dose of 4 mg/kg BW for a period of 6 weeks. Inflammation, steatosis, α-smooth muscle actin (α-SMA), and cytochrome P450 2E1 (CYP 2E1) expression increased significantly in the rats fed HFD and decreased in the rats administered by lycopene. Significantly elevated levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor (TNF α), and serum and liver malondialdehyde (MDA) were observed in rats fed the high-fat diet as compared to the control rats (P < .01). Supplementation with lycopene lowered serum MDA and tumor necrosis factor (TNF-α) levels and elevated liver GSH level (P < .001). Insulin resistance was higher in the rats fed HFD than in rats supplemented with lycopene. The data indicate that supplementation with lycopene can reduce high-fat diet-induced oxidative stress to the cells

Gastric Necrosis due to Acute Massive Gastric Dilatation

Gastric necrosis due to acute massive gastric dilatation is relatively rare. Vascular reasons, herniation, volvulus, acute gastric dilatation, anorexia, and bulimia nervosa play a role in the etiology of the disease. Early diagnosis and treatment are highly important as the associated morbidity and mortality rates are high. In this case report, we present a case of gastric necrosis due to acute gastric dilatation accompanied with the relevant literature

Zolmitriptan-induced acute myocardial infarction

Triptans are an established treatment for acute migraine attacks. By activating 5HT1B/1D receptors they lead to vasoconstriction of the cerebral blood vessels which are dilated during migraine attacks. Moreover, they reduce secretion of vasoactive peptides and conduction of pain stimuli over the cerebral cortex. In up to 7% of cases of treatment with triptans, thoracic pain occurs, although this is mostly transient, mild and without lasting ischemia. We present the case of a 45 year-old woman with a history of migraine with visual aura since the age of 20. She had no history of diabetes mellitus, hypertension, smoking or any other risk factors for cardiovascular events before she was admitted to our emergency room with typical chest pain. An electrocardiogram revealed anterior myocardial infarction following her monthly dose of oral zolmitriptan. Catherization revealed a normal coronary arterial system. The laboratory indices for cardiac risk were within normal ranges. The patient was advised to avoid triptans permanently on being discharged. (Cardiol J 2012; 19, 1: 76&#8211;78

Changes in the chemical structure and decay resistance of heat-treated narrow-leaved ash wood

We analyzed the effects of heat treatment on the chemical structure of wood from narrow-leafed Ash (Fraxinus angustifolia), a fast-growing and economically valuable species. We also analyzed the effects of heat treatment on the wood’s resistance to four decay fungi. Narrow-leafed Ash wood samples were heated with saturated steam to 140, 180, 200, and 220°C for 2, 4, and 6 h. The relative contents of extractable components were analyzed, as well as the levels of holocellulose, cellulose, and lignin. In addition, the density, equilibrium moisture content, and pH of the samples were measured. To determine the effects of heat treatment on resistance to decay fungi, the samples were exposed to the white rot fungus Trametes versicolor, dry rot fungus Serpula lacrymans, and the brown rot fungi Coniophora puteana and Gloeophyllum trabeum. Changes in the chemical composition of the wood due to heat treatment were correlated with increased resistance to fungal decay. While the hemicellulose content was dramatically reduced with increasing temperature and treatment duration, the lignin content increased proportionately. Thus, heat treatment is an environmentally friendly method of preserving narrow-leafed Ash wood against various decay fungi