One of the main contributions of the Capital Assets Pricing Model (CAPM) to portfolio theory was to explain the correlation between assets through its relationship with the market index. According to ...this approach, the market index is expected to explain the co-movement between two different stocks to a great extent. In this paper, we try to verify this hypothesis using a sample of 3.000 stocks of the USA market (attending to liquidity, capitalization, and free float criteria) by using some functions inspired by cooperative dynamics in physical particle systems. We will show that all of the co-movement among the stocks is completely explained by the market, even without considering the market beta of the stocks.
Lactococcus lactis subsp. lactis bv. diacetylactis strains are aroma-producing organisms used in starter cultures for the elaboration of dairy products. This species is essentially a fermentative ...microorganism, which cometabolizes glucose and citrate to yield aroma compounds through the diacetyl/acetoin biosynthetic pathway. Our previous results have shown that under acidic growth Lactococcus bv. diacetylactis CRL264 expresses coordinately the genes responsible for citrate transport and its conversion into pyruvate. In the present work the impact of acidic growth on glucose, citrate, and pyruvate metabolism of Lactococcus bv. diacetylactis CRL264 has been investigated by proteomic analysis. The results indicated that acid growth triggers the conversion of citrate, but not glucose, into α-acetolactate via pyruvate. Moreover, they showed that low pH has no influence on levels of lactate dehydrogenase and pyruvate dehydrogenase. Therefore, the influence of external pH on regulation of the diacetyl/acetoin biosynthetic pathway in Lactococcus bv. diacetylactis CRL264 has been analyzed at the transcriptional level. Expression of the als, aldB, aldC, and butBA genes encoding the enzymes involved in conversion of pyruvate into aroma compounds has been investigated by primer extension, reverse transcription-PCR analysis, and transcriptional fusions. The results support that this biosynthetic pathway is induced at the transcriptional level by acidic growth conditions, presumably contributing to lactococcal pH homeostasis by synthesis of neutral compounds and by decreasing levels of pyruvate.
Background:
Effectiveness of corticosteroids in immunosuppressed patients with inflammatory bowel disease (IBD) has not been completely elucidated.
Aims:
To assess the effectiveness and examine the ...long-term follow-up of systemic or low-bioavailability oral steroid treatment for moderate flare-ups in patients treated with immunosuppressive drugs.
Methods:
Immunosuppressed patients with inflammatory bowel disease (IBD) from our population-data registry were analyzed. For statistical analysis, the chi-square test, Mann-Whitney U test, and Kaplan-Meier survival analysis were used as appropriate.
Results:
A total of 392 patients with IBD and a median of 82 (range, 6–271) months of immunosuppressive (IMM) treatment were identified. The mean follow-up was 87 months (range, 6–239 months). A total of 89 patients (23%) needed at least one steroid course during their follow-up. Average time from IMM to steroid treatment was 26 (range, 6–207) months. In patients with CD, fibrostenotic (B2) and fistulizing (B3) behaviors
p
= 0.005; odds ratio (OR): 2.284 were risk factors for using steroids after IMM treatment. In patients with UC, no statistically significant variables were identified. Of the 89 patients who received one first steroid course, 49 (55%) stepped up to biological treatment or surgery after a median of 13 months (range, 0–178), 19 (21%) were treated with repeated steroid courses, and 31 (35%) required no further treatment. Patients with CD had a higher risk (
p
= 0.007; OR: 3.529) of receiving biological treatment or surgery than patients with UC. The longer the patients with UC (more months) spent using steroids, the greater the risk of requiring treatment with biological drugs or surgery (
p
= 0.009).
Conclusion:
A total of 23% of the immunosuppressed patients with IBD received at least one course of steroid treatment. In patients under immunosuppression treated with at least a course of steroids, CD patients were more likely stepped up to biologics and/or surgery than UC patients. In patients with CD, B2/B3 behavior pattern were significant risk factors. After one course of steroids only 35% of immunosuppressed IBD patients remained in remission without needing treatment scalation.
The 1,3-dipolar cycloaddition of a chiral nitrone with α,β-unsaturated lactones was carried out to give the corresponding isoxazolidines. Tetrahydro-1,3-oxazines with an oxa-tropane skeleton were ...obtained in one step by alkylation. The structures of several of these compounds were corroborated by X-ray diffraction and molecular modelling studies confirmed the results and proposed a mechanism for their formation.
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•1,3-Dipolar cycloaddition of a chiral nitrone with α,β-unsaturated lactones was carried out to give the corresponding isoxazolidines.•Tetrahydro-1,3-oxazines with an oxa-tropane skeleton have been obtained in one step for the corresponding isoxazolidines.•A revised version of the proposed mechanism has been stablished using molecular modelling studies.•The structure of several of these compounds were corroborated by X-ray diffraction and NMR spectra has been completely stablished.
BACKGROUND Insulinomas are pancreatic neuroendocrine tumors that cause non-ketotic hypoglycemia due to hyperinsulinism; they are extremely rare, especially in children. CASE REPORT We present a case ...of a sporadic insulinoma in an 11-year-old boy who had episodes of self-limited drowsiness and behavior changes over a 3-month period, thought to be caused by psychological issues. Non-ketotic hypoglycemia was confirmed at our center. A fasting blood test found inappropriately elevated insulin levels during hypoglycemia, undetectable β-hydroxybutyrate, and increased C-peptide levels in line with insulin levels. Anti-insulin antibodies were negative and antidiabetic drugs untraceable. The glucagon-stimulation test was positive. Growth hormone, adrenocorticotropin hormone, and phosphorus and calcium metabolism were normal. Dual-phase computed tomography detected a lesion compatible with an insulinoma. Endoscopic ultrasound showed a homogenous lesion at the junction of the body and tail of the pancreas. Histologic analysis of a fine-needle aspiration biopsy was compatible with neuroendocrine neoplasia. Preoperatively, a fractional diet avoiding fast-absorbing carbohydrates maintained normal glucose blood levels. Enucleation was not possible, so the lesion was resected along with portions of the body and tail of the pancreas. The well-differentiated tumor measured 15 mm x 13 mm. Postoperative blood glucose levels were correct, allowing a normal diet. CONCLUSIONS In children with unspecific symptoms compatible with hypoglycemia, blood glucose must be evaluated to confirm low blood glucose levels. Determining blood ketone levels is important for the differential diagnosis. The diagnostic approach to pediatric insulinoma represents a challenge for multidisciplinary teamwork.
Human population growth and economic development threaten the integrity of freshwater ecosystems globally, reducing their ability to support biodiversity and provide ecosystem services. However, our ...knowledge of freshwater biodiversity is fragmented due to bias in conservation research toward primarily terrestrial or charismatic taxonomic groups. Here, we utilize the most comprehensive assessment of freshwater biodiversity for an entire continent to examine the implications of this shortfall. Results indicate that groups that have been the focus of most conservation research are poor surrogates for patterns of both richness and threat for many freshwater groups, and that the existing protected area network underrepresents freshwater species. Areas of highest species richness and threat are congruent with areas where reliance on ecosystem services by humans and pressures placed on freshwater ecosystems are high. These results have implications for targets to reduce biodiversity loss and safeguard associated ecosystem services on which millions of people depend globally.
Energy efficiency has become one of the basic pillars with which to tackle climate change in the European Union where households accounted for 27% of final energy consumption in the year 2016, the ...second largest sector after transport. This paper describes and draws conclusions from a series of economic experiments developed with the objective of analyzing the effectiveness of various methods for improving energy efficiency in the domestic sector. A distinction is made between informational methods, consisting in providing continuous information to the consumer about their energy performance, and economic methods which are based on an economic incentive calculated on the basis of the energy savings achieved with respect to a known reference. The experiments have been carried out both in the experimental economics laboratory and in the field (real dwellings) and have also made it possible to evaluate the applicability of experimental economics to this type of analysis, in which the economic behavior of the subjects is influenced by psychological and social aspects. Final results show that informational methods on their own are not sufficient to achieve and maintain substantial energy savings and should be accompanied by economic incentives.
This study combines insights from the entrepreneurship, competency-based view and innovation policy literature to analyze the relationships among different types of public incentives designed to ...foster innovation and product innovation at both new ventures and incumbent firms. To test our hypotheses, we ran a system of regression models on a cross-national sample comprised of 5238 firms from 29 European countries and found a different pattern for new ventures and incumbents. Our results suggest that support for attendance or participation in trade fairs and networking with other companies are the most effective methods of promoting product innovation for new ventures. However, for incumbent firms, we found that the most effective policies consisted of tax reduction for R&D expenditures and subsidies for acquiring buildings or other infrastructure(s) for innovation activities. This distinction prompts interesting insights related to theory development in research on entrepreneurship and innovation policy.
•We examine the differentiated effects of public instruments on product innovation.•We found a different pattern for new ventures and incumbents.•The most effective public support instruments are:•For new ventures, support for trade fairs and networking with other companies.•For incumbents, tax reduction and subsidies for acquiring infrastructure.
• Background and Aims The use of grafted plants in vegetable crop production is now being expanded greatly. However, few data are available on the formation of graft unions in vegetables. In this ...work, the structural development of the graft union formation in tomato plants is studied, together with the possible relationship with activities of peroxidases and catalases. • Methods Tomato (Lycopersicon esculentum Mill.) seedlings of cultivar Fanny were grafted on the rootstock of cultivar AR‐9704 using the ‘tongue approach grafting’ method, and were grown in a crop chamber. A study of the structural development of the graft union and the involvement of peroxidases and catalases in the process of graft formation was carried out during the first stages of the graft union (4, 8 and 15 d after grafting). • Key Results Observation of the structure of the graft union showed formation of xylem and phloem vessels through the graft union 8 d after grafting. In addition, root hydraulic conductance, L0, indicate that the graft union is fully functional 8 d after grafting, which coincided with an increase of peroxidase and catalase activities. • Conclusions These results suggest that increased peroxidase and catalase activities might be implicated in graft development in tomato plants.
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