367 research outputs found
Twinning superlattices in indium phosphide nanowires
Here, we show that we control the crystal structure of indium phosphide (InP)
nanowires by impurity dopants. We have found that zinc decreases the activation
barrier for 2D nucleation growth of zinc-blende InP and therefore promotes the
InP nanowires to crystallise in the zinc blende, instead of the commonly found
wurtzite crystal structure. More importantly, we demonstrate that we can, by
controlling the crystal structure, induce twinning superlattices with
long-range order in InP nanowires. We can tune the spacing of the superlattices
by the wire diameter and the zinc concentration and present a model based on
the cross-sectional shape of the zinc-blende InP nanowires to quantitatively
explain the formation of the periodic twinning.Comment: 18 pages, 4 figure
The effect of ad appeals and message framing on consumer responses to plant-based menu items
While the recent surge of meat-like items on restaurant menus has received considerable attention, little is known how to encourage consumers to choose such novel dishes. To address this gap, we investigate the role of various communication strategies in making plant-based menu items more attractive. The results from Study 1 suggest that using a social appeal in the ad increases consumers’ preference for plant-based menu items via anticipated pleasure, but a health appeal does not. The results from Study 2 demonstrate that information on social costs induces feelings of ambivalence toward meat eating, thus making plant-based menu items more desirable. However, information on health risks of meat consumption does not have such an effect. Practical implications for promoting plant-based menu items are discussed
On the Importance of Complaint Handling Design : A Multi-Level Analysis of the Impact in Specific Complaint Situations
Given the large investments required for high-quality complaint handling design,
managers need practical guidance in understanding its actual importance for their
particular company. However, while prior research emphasizes the general relevance
of complaint handling design, it fails to provide a more differentiated perspective on
this interesting issue. This study, which is based on an integrative multi-level
framework and a dyadic dataset, addresses this important gap in research. Results
indicate that the impact of a company’s complaint handling design varies significantly
depending on the characteristics of the complaining customers with which the firm has
to deal. Further, this paper shows that, contingent on these characteristics, a company’s
complaint handling design can shape complainants’ fairness perceptions either
considerably or only slightly. Overall, findings suggest that companies should apply
an adaptive approach to complaint handling to avoid misallocation of attention,
energy, and resources
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Airway obstruction, serum vitamin D and mortality in a 33-year follow-up study
Background and objective: Chronic obstructive pulmonary disease and low vitamin D status predict mortality, but their combined effect on mortality remains inconclusive. We aimed to investigate a joint effect of airway obstruction and vitamin D status on mortality in a nationally representative cohort. Methods: We analysed data of 6676 Finnish adults participating between 1978 and 1980 in a national health examination survey, undergoing spirometry and having all necessary data collected. We followed them up in national registers through record linkage until 31 December 2011. We categorised the subjects with obstruction using the lower limit of normal (LLN) and the measured serum 25-hydroxyvitamin-D (s-25(OH)D) into tertiles. Results: Both obstruction and low s-25(OH) D independently predicted mortality in a multivariate model adjusted also for age, sex, smoking, education, leisure physical activity, body mass index, asthma and serum C-reactive protein. However, a statistically significant (p = 0.007) interaction emerged: the adjusted mortality HRs (95% CI's) for s-25(OH)D in tertiles among the subjects without and with obstruction were 1.00 (lowest), 0.96 (0.87-1.05) and 0.89 (0.81-0.98); and 1.00, 0.96 (0.71-1.31) and 0.57 (0.40-0.80), respectively. Conclusions: In conclusion, obstruction and low s-25(OH)D predict mortality independently of each other. Our findings suggest that low vitamin D status might be particularly detrimental among subjects with obstruction.Peer reviewe
Tumor tissue levels of Tissue Inhibitor of Metalloproteinases-1 (TIMP-1) and outcome following adjuvant chemotherapy in premenopausal lymph node-positive breast cancer patients: A retrospective study
<p>Abstract</p> <p>Background</p> <p>We have previously demonstrated that high tumor tissue levels of TIMP-1 are associated with no or limited clinical benefit from chemotherapy with CMF and anthracyclines in metastatic breast cancer patients. Here, we extend our investigations to the adjuvant setting studying outcome after adjuvant chemotherapy in premenopausal lymph node-positive patients. We hypothesize that TIMP-1 high tumors are less sensitive to chemotherapy and accordingly that high tumor tissue levels are associated with shorter survival.</p> <p>Methods</p> <p>From our original retrospectively collected tumor samples we selected a group of 525 pre-menopausal lymph node-positive patients (adjuvant treatment: CMF, 324 patients; anthracycline-based, 99 patients; no adjuvant chemotherapy, 102 patients). TIMP-1 levels were measured using ELISA in cytosolic extracts of frozen primary tumors. TIMP-1 was analyzed as a continuous variable and as a dichotomized one using the median TIMP-1 concentration as a cut point between high and low TIMP-1 groups. We analyzed the benefit of adjuvant CMF and anthracyclines in univariate and multivariable survival models; endpoints were disease-free (DFS) and overall survival (OS).</p> <p>Results</p> <p>In this selected cohort of high-risk patients, and in the subgroup of patients receiving no adjuvant therapy, TIMP-1 was not associated with prognosis. In the subgroup of patients treated with anthracyclines, when analyzed as a continuous variable we observed a tendency for increasing TIMP-1 levels to be associated with shorter DFS (multivariable analysis, HR 1.75, 95% CI 1.00-3.07, P = 0.05) and a significant association between increasing TIMP-1 and shorter OS in both univariate (HR 3.52, 95% CI 1.54-8.06, P = 0.003) and multivariable analyses (HR 4.19, 95% CI 1.67-10.51, P = 0.002). No statistically significant association between TIMP-1 and DFS was observed in the CMF-treated patients although high TIMP-1 was associated with shorter OS when analyzed as a dichotomized variable (HR 1.64, 95% CI 1.02-2.65, P = 0.04).</p> <p>Conclusion</p> <p>In the subgroup of patients receiving adjuvant chemotherapy we found an association between shorter survival after treatment in TIMP-1 high patients compared with TIMP-1 low patients, especially in patients receiving anthracycline-based therapy. This suggests that high tumor tissue levels of TIMP-1 might be associated with reduced benefit from classical adjuvant chemotherapy. Our findings should be validated in larger prospective studies.</p
Operative versus non-operative treatment for 2-part proximal humerus fracture: A multicenter randomized controlled trial
Background Although increasingly used, the benefit of surgical treatment of displaced 2-part proximal humerus fractures has not been proven. This trial evaluates the clinical effectiveness of surgery with locking plate compared with non-operative treatment for these fractures. Methods and findings The NITEP group conducted a superiority, assessor-blinded, multicenter randomized trial in 6 hospitals in Finland, Estonia, Sweden, and Denmark. Eighty-eight patients aged 60 years or older with displaced (more than 1 cm or 45 degrees) 2-part surgical or anatomical neck proximal humerus fracture were randomly assigned in a 1:1 ratio to undergo either operative treatment with a locking plate or non-operative treatment. The mean age of patients was 72 years in the non-operative group and 73 years in the operative group, with a female sex distribution of 95% and 87%, respectively. Patients were recruited between February 2011 and April 2016. The primary outcome measure was Disabilities of Arm, Shoulder, and Hand (DASH) score at 2-year follow-up. Secondary outcomes included Constant–Murley score, the visual analogue scale for pain, the quality of life questionnaire 15D, EuroQol Group’s 5- dimension self-reported questionnaire EQ-5D, the Oxford Shoulder Score, and complications. The mean DASH score (0 best, 100 worst) at 2 years was 18.5 points for the operative treatment group and 17.4 points for the non-operative group (mean difference 1.1 [95% CI −7.8 to 9.4], p = 0.81). At 2 years, there were no statistically or clinically significant between-group differences in any of the outcome measures. All 3 complications resulting in secondary surgery occurred in the operative group. The lack of blinding in patient-reported outcome assessment is a limitation of the study. Our assessor physiotherapists were, however, blinded. Conclusions This trial found no significant difference in clinical outcomes at 2 years between surgery and non-operative treatment in patients 60 years of age or older with displaced 2-part fractures of the proximal humerus. These results suggest that the current practice of performing surgery on the majority of displaced proximal 2-part fractures of the humerus in older adults may not be beneficial. Trial registration ClinicalTrials.gov NCT01246167.Peer reviewe
Online brand communities: when consumers are negatively engaged
The goal of the current research is to explore the influence of negative engagement on committing participants in hate online brand communities. To reach this aim, three brands are used to assess this phenomenon (Starbucks, Apple, and McDonald’s), and three related hate online brand communities of such brands are involved. An online questionnaire is developed based on previously validated scales and fulfilled by 300 online members of mentioned communities. Findings reveal the importance of Brand influence, Helping, and Self-expression dimensions on participants to be committed to hating brand communities.info:eu-repo/semantics/acceptedVersio
Correlation between MMPs and their inhibitors in breast cancer tumor tissue specimens and in cell lines with different metastatic potential
Background: The metastatic disease rather than the primary tumor itself is responsible for death in most solid tumors, including breast cancer. The role of matrix metalloproteinases ( MMPs), tissue inhibitors of MMPs (TIMPs) and Reversion-inducing cysteine-rich protein with Kazal motifs ( RECK) in the metastatic process has previously been established. However, in all published studies only a limited number of MMPs/MMP inhibitors was analyzed in a limited number of cell lines. Here, we propose a more comprehensive approach by analyzing the expression levels of several MMPs (MMP-2, MMP-9 and MMP-14) and MMP inhibitors (TIMP-1, TIMP-2 and RECK) in different models ( five human breast cancer cell lines, 72 primary breast tumors and 30 adjacent normal tissues). Methods: We analyzed the expression levels of MMP-2, MMP-9 and MMP-14 and their inhibitors (TIMP-1, TIMP-2 and RECK) by quantitative RT-PCR (qRT-PCR) in five human breast cancer cell lines presenting increased invasiveness and metastatic potential, 72 primary breast tumors and 30 adjacent normal tissues. Moreover, the role of cell-extracellular matrix elements interactions in the regulation of expression and activity of MMPs and their inhibitors was analyzed by culturing these cell lines on plastic or on artificial ECM (Matrigel). Results: The results demonstrated that MMPs mRNA expression levels displayed a positive and statistically significant correlation with the transcriptional expression levels of their inhibitors both in the cell line models and in the tumor tissue samples. Furthermore, the expression of all MMP inhibitors was modulated by cell-Matrigel contact only in highly invasive and metastatic cell lines. The enzyme/inhibitor balance at the transcriptional level significantly favors the enzyme which is more evident in tumor than in adjacent non-tumor tissue samples. Conclusion: Our results suggest that the expression of MMPs and their inhibitors, at least at the transcriptional level, might be regulated by common factors and signaling pathways. Therefore, the multi-factorial analysis of these molecules could provide new and independent prognostic information contributing to the determination of more adequate therapy strategies for each patient.`Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Pesquisa (CNPq)Financiadora de Estudos e Projetos (FINEP)Pro-Reitoria da Universidade de Sao Paulo (PRP-USP
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