Unlocking thermal comfort in transitional spaces: A field study in three Italian shopping centres

Shopping centres are commonly laid out as small individual stores connected by transitional spaces. Setpoint temperatures used to control transitional spaces are normally the same as in traditional indoor environments despite substantial differences in use, time of permanence and users' needs. Currently, there are no comfort guidelines for transitional spaces and the literature lacks relevant studies on the topic. There is an untapped potential for energy savings and improved indoor environmental quality. The main objective of this work is to evaluate the suitability of Fanger's comfort model and adaptive comfort model for transitional spaces. We assessed users' thermal perception and potential impacting factors in three Italian shopping centres. 724 customers were interviewed on their thermal comfort, thermal sensation, thermal preference, and clothing level while experiencing the transitional space. In addition, the thermal environment at the interview locations (dry-bulb temperature, globe temperature, relative humidity, and air speed at different levels) and the outdoor temperature were monitored. The study demonstrated that Fanger's model and the adaptive comfort model are not suitable for transitional spaces. Customers were inclined to adapt to a much wider range of indoor environmental conditions. An operative temperature of up to 27.5 °C was still deemed comfortable by more than 80% of the customers. These results unlock a large potential for energy savings and pave the way for passive solutions such as natural ventilation

AEROBIC AND ANAEROBIC METABOLISM DURING LOCOMOTION WITH TWO DIFFERENT WHEELCHAIR TYPES

Wheelchair design is extremely important in order to improve efficiency of locomotion and reduce physical stress in subjects whose muscular and cardiopulmonary fitness are impaired. Purpose of this study was to evaluate the effect of different wheelchair design on the aerobic and anaerobic metabolism during locomotion at different speeds in paraplegic subjects. The experiments were carried out on a group of 5 male paraplegic subjects (25 ±3 years; body weight 65±7kg) during locomotion on a roller ergometer (Sopur, Ergotronic mod.) at 3-4 different speeds from 2 to 9 km/h. At each speed oxygen consumption and heart rate were determined after at least 6 min of exercise. Lactic acid (LA) venous blood concentration was evaluated before and at the 5th min of recovery and lactate production was calculated. The oxygen equivalent of LA was assumed to be 3.15ml O2 per kg body weight for an increase of blood LA of 1 mmol/L. For each subject the test was repeated using two different types of daily use active wheelchairs: type A., foldable, 13.95kg; type B, demountable, 13.35kg. The main difference in size was in the horizontal location of the wheel axle, in seat height and in handrim diameter. Results indicate that: a) oxygen consumption increased linearly with speed being 2050±350ml/min and 1780±270ml/min at 9km/h for wheelchair type A and B, respectively; b)lactic acid concentrations were significantly higher, at a given speed, while using wheelchair type A than B (at 9km/h; 7.4±1.5 mmol/l and 6.0±1.6 mmol/l, respectively),c) the total energy required , aerobic and anaerobic, increased linearly with speed and was 15-20% higher with wheelchair type A than B at all speeds; d) the energy cost of locomotion at a given speed was in the 15-25% range higher for wheelchair A than B; e) at corresponding oxygen uptake, heart rate and pulmonary ventilation were not different with the two wheelchair types. The main results of this study concern the large difference existing in the energy cost of locomotion and in the lactate production in the same subject when two different wheelchairs, even if apparently similar are used. In particular the much higher lactate production suggests that wheelchair design affects the limb and trunk movements in such a way that the metabolism of some muscle group requires a greater participation of anaerobic mechanism of energy supply, this leading to early onset of muscular fatigue. Further studies, in particular the combined biomechanical analysis of user and wheelchair during locomotion are required to increase the optimum fitting of wheelchair –user interface

Matrigel plug assay: evaluation of the angiogenic response by reverse transcription-quantitative PCR

The subcutaneous Matrigel plug assay in mice is a method of choice for the in vivo evaluation of pro- and anti-angiogenic molecules. However, quantification of the angiogenic response in the plug remains a problematic task. Here we report a simple, rapid, unbiased and reverse transcription-quantitative PCR (RT-qPCR) method to investigate the angiogenic process occurring in the Matrigel plug in response to fibroblast growth factor-2 (FGF2). To this purpose, a fixed amount of human cells were added to harvested plugs at the end of the in vivo experimentation as an external cell tracer. Then, mRNA levels of the panendothelial cell markers murine CD31 and vascular endothelial-cadherin were measured by species-specific RT-qPCR analysis of the total RNA and data were normalized for human GAPDH or b-actin mRNA levels. RTqPCR was used also to measure the levels of expression in the plug of various angiogenesis/inflammation-related genes. The procedure allows the simultaneous, quantitative evaluation of the newly-formed endothelium and of nonendothelial/ inflammatory components of the cellular infiltrate in the Matrigel implant, as well as the expression of genes involved in the modulation of the angiogenesis process. Also, the method consents the quantitative assessment of the effect of local or systemic administration of anti-angiogenic compounds on the neovascular response triggered by FGF

Cutting edge: extracellular high mobility group box-1 protein is a proangiogenic cytokine.

The chromosomal high mobility group box-1 (HMGB1) protein acts as a proinflammatory cytokine when released in the extracellular environment by necrotic and inflammatory cells. In the present study, we show that HMGB1 exerts proangiogenic effects by inducing MAPK ERK1/2 activation, cell proliferation, and chemotaxis in endothelial cells of different origin. Accordingly, HMGB1 stimulates membrane ruffling and repair of a mechanically wounded endothelial cell monolayer and causes endothelial cell sprouting in a three-dimensional fibrin gel. In keeping with its in vitro properties, HMGB1 stimulates neovascularization when applied in vivo on the top of the chicken embryo chorioallantoic membrane whose blood vessels express the HMGB1 receptor for advanced glycation end products (RAGE). Accordingly, RAGE blockade by neutralizing Abs inhibits HMGB1-induced neovascularization in vivo and endothelial cell proliferation and membrane ruffling in vitro. Taken together, the data identify HMGB1/RAGE interaction as a potent proangiogenic stimulus

Cyclic shear tests on RC precast beam-to-column connections retrofitted with a three-hinged steel device

Recent European earthquakes demonstrated that the seismic response of RC precast structures can be significantly influenced by the connection systems. Moreover, during past seismic events, many failures of the beam-to-column connections occurred due to their inadequate strength under seismic loads. The seismic safety of these connections has a crucial role in the overall seismic capacity of existing precast structures. A new connection system is employed as a retrofitting solution for a damaged beam-to-column connection and its cyclic shear performance is investigated by means of two cyclic shear tests on two different configurations. In both the experimental tests, the results demonstrate an efficient behavior of the retrofitted connections under horizontal cyclic loads. The comparison between the performance of the investigated connection and the response of a typical beam-to-column dowel connection allows to discuss the main critical features of the dowel connection system

Anti-angiogenic activity of the flavonoid precursor 4-hydroxychalcone.

Angiogenesis, the growth of new blood vessels, is necessary for cancerous tumors to keep growing and spreading. Suppression of abnormal angiogenesis may provide therapeutic strategies for the treatment of angiogenesis-dependent disorders. In the present study, we describe the in vitro and in vivo anti-angiogenic activities of the flavonoid precursor 4-hydroxychalcone (Q797). This chalcone (22μg/ml) suppressed several steps of angiogenesis, including endothelial cell proliferation, migration and tube formation without showing any signs of cytotoxicity. Moreover, we found a selective effect on activated endothelial cells, in particular with resting endothelial cells and the human epithelial tumor cell lines (HeLa, MCF-7, A549). In addition, Q797 was able to modulate both vascular endothelial growth factor (VEGF)- and basic fibroblast growth factor (FGF)- induced phosphorylation of extracellular signal-regulated kinase (ERK)-1/-2 and Akt kinase. It did not influence the nuclear translocation of p65 subunit of the nuclear factor-κB (NF-κB) when human endothelial cells were stimulated with tumor necrosis factor (TNF)-α. Taken together this indicates that the Q797-mediated inhibition of in vitro angiogenic features of endothelial cells is most likely caused by suppression of growth factor pathways. The potent inhibitory effect of Q797 on bFGF-driven neovascularization was also demonstrated in vivo using the chick chorioallantoic membrane (CAM) assay. In summary, this chalcone could serve as a new leading structure in the discovery of new potent synthetic angiogenesis inhibitors

A variational approach to strongly damped wave equations

We discuss a Hilbert space method that allows to prove analytical well-posedness of a class of linear strongly damped wave equations. The main technical tool is a perturbation lemma for sesquilinear forms, which seems to be new. In most common linear cases we can furthermore apply a recent result due to Crouzeix--Haase, thus extending several known results and obtaining optimal analyticity angle.Comment: This is an extended version of an article appeared in \emph{Functional Analysis and Evolution Equations -- The G\"unter Lumer Volume}, edited by H. Amann et al., Birkh\"auser, Basel, 2008. In the latest submission to arXiv only some typos have been fixe

The COOH-Terminal Peptide of Platelet Factor-4 Variant (CXCL4L1/PF-4var47-70) Strongly Inhibits Angiogenesis and Suppresses B16 Melanoma Growth In vivo.

Chemokines influence tumor growth directly or indirectly via both angiogenesis and tumor-leukocyte interactions. Platelet factor-4 (CXCL4/PF-4), which is released from alpha-granules of activated platelets, is the first described angiostatic chemokine. Recently, it was found that the variant of CXCL4/PF-4 (CXCL4L1/PF-4var) could exert a more pronounced angiostatic and antitumoral effect than CXCL4/PF-4. However, the molecular mechanisms of the angiostatic activities of the PF-4 forms remain partially elusive. Here, we studied the biological properties of the chemically synthesized COOH-terminal peptides of CXCL4/PF-4 (CXCL4/PF-4(47-70)) and CXCL4L1/PF-4var (CXCL4L1/PF-4var(47-70)). Both PF-4 peptides lacked monocyte and lymphocyte chemotactic activity but equally well inhibited (25 nmol/L) endothelial cell motility and proliferation in the presence of a single stimulus (i.e., exogenous recombinant fibroblast growth factor-2). In contrast, when assayed in more complex angiogenesis test systems characterized by the presence of multiple mediators, including in vitro wound-healing (2.5 nmol/L versus 12.5 nmol/L), Matrigel (60 nmol/L versus 300 nmol/L), and chorioallantoic membrane assays, CXCL4L1/PF-4var(47-70) was found to be significantly (5-fold) more angiostatic than CXCL4/PF-4(47-70). In addition, low (7 mug total) doses of intratumoral CXCL4L1/PF-4var(47-70) inhibited B16 melanoma growth in mice more extensively than CXCL4/PF-4(47-70). This antitumoral activity was predominantly mediated through inhibition of angiogenesis (without affecting blood vessel stability) and induction of apoptosis, as evidenced by immunohistochemical and fluorescent staining of B16 tumor tissue. In conclusion, CXCL4L1/PF-4var(47-70) is a potent antitumoral and antiangiogenic peptide. These results may represent the basis for the design of CXCL4L1/PF-4var COOH-terminal-derived peptidomimetic anticancer drugs. Mol Cancer Res; 8(3); 322-34

Antiangiogenic activity of semisynthetic biotechnological heparins: low-molecular-weight-sulfated Escherichia coli K5 polysaccharide derivatives as fibroblast growth factor antagonists.

OBJECTIVE: Low-molecular-weight heparin (LMWH) exerts antitumor activity in clinical trials. The K5 polysaccharide from Escherichia coli has the same structure as the heparin precursor. Chemical and enzymatic modifications of K5 polysaccharide lead to the production of biotechnological heparin-like compounds. We investigated the fibroblast growth factor-2 (FGF2) antagonist and antiangiogenic activity of a series of LMW N,O-sulfated K5 derivatives. METHODS AND RESULTS: Surface plasmon resonance analysis showed that LMW-K5 derivatives bind FGF2, thus inhibiting its interaction with heparin immobilized to a BIAcore sensor chip. Interaction of FGF2 with tyrosine-kinase receptors (FGFRs), heparan sulfate proteoglycans (HSPGs), and alpha(v)beta3 integrin is required for biological response in endothelial cells. Similar to LMWH, LMW-K5 derivatives abrogate the formation of HSPG/FGF2/FGFR ternary complexes by preventing FGF2-mediated attachment of FGFR1-overexpressing cells to HSPG-bearing cells and inhibit FGF2-mediated endothelial cell proliferation. However, LMW-K5 derivatives, but not LMWH, also inhibit FGF2/alpha(v)beta3 integrin interaction and consequent FGF2-mediated endothelial cell sprouting in vitro and angiogenesis in vivo in the chick embryo chorioallantoic membrane. CONCLUSIONS: LMW N,O-sulfated K5 derivatives affect both HSPG/FGF2/FGFR and FGF2/alpha(v)beta3 interactions and are endowed with FGF2 antagonist and antiangiogenic activity. These compounds may provide the basis for the design of novel LMW heparin-like angiostatic compounds