7,839 research outputs found
Mechanical behavior of optimized optical nanomultilayers
Please click Additional Files below to see the full abstract
How and when do big data investments pay off? The role of marketing affordances and service innovation
Big data technologies and analytics enable new digital services and are often associated with superior performance. However, firms investing in big data often fail to attain those advantages. To answer the questions of how and when big data pay off, marketing scholars need new theoretical approaches and empirical tools that account for the digitized world. Building on affordance theory, the authors develop a novel, conceptually rigorous, and practice-oriented framework of the impact of big data investments on service innovation and performance. Affordances represent action possibilities, namely what individuals or organizations with certain goals and capabilities can do with a technology. The authors conceptualize and operationalize three important big data marketing affordances: customer behavior pattern spotting, real-time market responsiveness, and data-driven market ambidexterity. The empirical analysis establishes construct validity and offers a preliminary nomological test of direct, indirect, and conditional effects of big data marketing affordances on perceived big data performance
Effect on albumin and fibronectin adsorption of silver doping via ionic exchange of a silica-based bioactive glass
Protein adsorption is a crucial step in the life of biomaterials for bone application, such as bioactive glasses. The
investigation of adsorption mechanisms is a difficult task per se, which is even more complex on bioactive glasses
due to surface reactivity. Here, the effect of silver doping by ionic exchange on the interaction of a silica-based
bioactive glass with albumin and fibronectin, serum proteins related to osseointegration, is reported. The
presence of silver does not change relevant surface properties such as topography, surface energy, wettability, or
surface ζ potential. Nevertheless, the interactions with proteins are much different. The presence of silver
significantly increases the adsorption of albumin and fibronectin and leads to a higher loss of secondary structure
compared to the undoped surface, as a consequence of the interactions and bonding between silver and thiols in
the cysteine residues. Selectivity of silver-doped glass is discovered: Ag enhances more adsorption and dena-
turation of albumin since it has more cysteines than fibronectin. It is also here observed that due to the formation
of a hydrated silica gel layer during adsorption, proteins are not only present on the surface of the bioactive
glasses, but also embedded inside the surface reaction laye
A strong-coupling analysis of two-dimensional O(N) sigma models with on square, triangular and honeycomb lattices
Recently-generated long strong-coupling series for the two-point Green's
functions of asymptotically free lattice models are
analyzed, focusing on the evaluation of dimensionless renormalization-group
invariant ratios of physical quantities and applying resummation techniques to
series in the inverse temperature and in the energy . Square,
triangular, and honeycomb lattices are considered, as a test of universality
and in order to estimate systematic errors. Large- solutions are carefully
studied in order to establish benchmarks for series coefficients and
resummations. Scaling and universality are verified. All invariant ratios
related to the large-distance properties of the two-point functions vary
monotonically with , departing from their large- values only by a few per
mille even down to .Comment: 53 pages (incl. 5 figures), tar/gzip/uuencode, REVTEX + psfi
Quadrupole scan emittance measurements for the ELI-NP compton gamma source
The high brightness electron LINAC of the Compton
Gamma Source at the ELI Nuclear Physics facility in Roma-
nia is accelerating a train of 32 bunches with a nominal total
charge of
250 pC
and nominal spacing of
16 ns
. To achieve
the design gamma flux, all the bunches along the train must
have the designed Twiss parameters. Beam sizes are mea-
sured with optical transition radiation monitors, allowing a
quadrupole scan for Twiss parameters measurements. Since
focusing the whole bunch train on the screen may lead to
permanent screen damage, we investigate non-conventional
scans such as scans around a maximum of the beam size
or scans with a controlled minimum spot size. This paper
discusses the implementation issues of such a technique in
the actual machine layou
Local treatment with electrochemotherapy of superficial angiosarcomas: Efficacy and safety results from a multi-institutional retrospective study
Background:
Angiosarcoma is an aggressive vascular neoplasm with a high propensity for local recurrence. Electrochemotherapy is an emerging
skin-directed therapy, exerting prominent cytotoxic activity, and antivascular effects. Its efficacy in angiosarcoma has not been investigated.
Methods:
This multicenter retrospective analysis reviewed patients who underwent electrochemotherapy from 2007 to 2014 for superficial
advanced angiosarcomas. Bleomycin was administered intravenously and delivered within tumors by means of percutaneously applied electric
pulses, according to the European Standard Operating Procedures for Electrochemotherapy. Tumor assessment was performed using RECIST
(version 1.1). Toxicity (CTCAE, v4.0) and local progression-free survival (LPFS) were also evaluated.
Results:
Nineteen patients (13 with locally advanced and 6 with metastatic angiosarcomas) were treated. Tumor sites were: scalp (n¼5), breast(n¼8), other skin sites (n¼3), and soft tissue (n¼3). Target lesions (n¼54) ranged in size from 1.5 to 2.5 cm (median, 2 cm). Treatment was well tolerated. After 2 months, an objective response was observed in 12/19 (63%) patients, complete in 8 (42%). One-year LPFS within treatment field was 68%. Local symptom improvement included palliation of bleeding (5/19 patients) and pain relief (6/19 patients).
Conclusions:
Electrochemotherapy may represent a new locoregional treatment for selected patients with superficial angiosarcomas
Endovascular management of giant visceral artery aneurysms
Endovascular management of small visceral artery aneurysms is an established treatment with satisfactory outcomes. However, when size exceeds 5 cm visceral aneurysms are considered as “giant” (giant visceral artery aneurysms or GVAAs) and management is significantly more complex. Between August 2007 and June 2019 eleven cases of GVAAs that were endovascularly treated were retrospectively reviewed and included in this single center study. Mean size was 80 mm (± 26.3 mm) x 46 mm (+ -11.8 mm). Nine of the lesions were true aneurysms, and two were pseudoaneurysms. In 8 patients, the lesion was causing compression symptoms in the surrounding organs, one patient developed a contained rupture while 2 patients were completely asymptomatic. However, all patients were hemodynamically stable at the time of treatment. Technical success was defined as immediate complete exclusion of the aneurysmal sac, and clinical success as complete relief from clinical symptoms. Follow-up was performed with CT angiography, ultrasound and clinical examination. Mean follow-up was 45 months (range 6–84). Technical and clinical success were both 91%. Complications were one lack of control of contained rupture that was subsequently operated, one case of self-limiting non-target spleen embolization and one case of splenic abscess. Three patients died, one due to the contained rupture 15 days after procedure, the other two for other causes and occurred during the long-term follow-up. This series suggests that endovascular treatment of giant visceral artery aneurysms and pseudoaneuryms is a valid minimally invasive solution with very satisfactory immediate and long-term outcomes unless the aneurysm is already ruptured. A variety of endovascular tools may be required for successful treatment
- …