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1.
Unmet needs in the treatment of psoriasis call for novel therapeutic strategies. Pustular psoriasis and psoriatic arthritis often represent a therapeutic challenge. Focus on IL-36 cytokines offers an interesting approach, as the IL-36 axis has been appointed a critical driver of the autoinflammatory responses involved in pustular psoriasis. Two IL-36R blocking antibodies, imsidolimab and spesolimab, are currently undergoing phase II and III clinical trials, with promising results.  相似文献   
2.
A simple but comprehensive model considering homogeneous and micellar nucleation, coagulation, entry of radicals to particles and to micelles and radicals' exit from particles, is presented. The model is validated, in a starved semicontinuous heterophase polymerization of ethyl methacrylate, at three monomer addition rates. The model accurately describes the overall and instantaneous conversion, the average particle density and diameter, and the number and weight average molar masses evolutions over time. It is found that even though the average number of radicals is much smaller than 0.5, the system is not 0-1. An empirical function was used to describe the gel effect. The homogeneous nucleation was the prevailing mechanism for particle formation and large exit rates of radicals were observed. POLYM. ENG. SCI., 60: 223–232, 2019. © 2019 Society of Plastics Engineers  相似文献   
3.
Diabetic retinopathy (DR) is a complication of diabetes mellitus that appears in the retina. Clinitians use retina images to detect DR pathological signs related to the occlusion of tiny blood vessels. Such occlusion brings a degenerative cycle between the breaking off and the new generation of thinner and weaker blood vessels. This research aims to develop a suitable retinal vasculature segmentation method for improving retinal screening procedures by means of computer-aided diagnosis systems. The blood vessel segmentation methodology relies on an effective feature selection based on Sequential Forward Selection, using the error rate of a decision tree classifier in the evaluation function. Subsequently, the classification process is performed by three alternative approaches: artificial neural networks, decision trees and support vector machines. The proposed methodology is validated on three publicly accessible datasets and a private one provided by Hospital Sant Joan of Reus. In all cases we obtain an average accuracy above 96% with a sensitivity of 72% in the blood vessel segmentation process. Compared with the state-of-the-art, our approach achieves the same performance as other methods that need more computational power. Our method significantly reduces the number of features used in the segmentation process from 20 to 5 dimensions. The implementation of the three classifiers confirmed that the five selected features have a good effectiveness, independently of the classification algorithm.  相似文献   
4.
A study is presented of the nanomechanical phenomena experienced by nanoparticle‐conjugated biomolecules. A thermodynamic framework is developed to describe the binding of thrombin‐binding aptamer (TBA) to thrombin when the TBA is conjugated to nanorods. Binding results in nanorod aggregation (viz. directed self‐assembly), which is detectable by absorption spectroscopy. The analysis introduces the energy of aggregation, separating it into TBA–thrombin recognition and surface‐work contributions. Consequently, it is demonstrated that self‐assembly is driven by the interplay of surface work and thrombin‐TBA recognition. It is shown that the work at the surface is about ?10 kJ mol?1 and results from the accumulation of in‐plane molecular forces of pN magnitude and with a lifetime of <1 s, which arises from TBA nanoscale rearrangements fuelled by thrombin‐directed nanorod aggregation. The obtained surface work can map aggregation regimes as a function of different nanoparticle surface conditions. Also, the thermodynamic treatment can be used to obtain quantitative information on surface effects impacting biomolecules on nanoparticle surfaces.  相似文献   
5.
The synthesis by semicontinuous heterophase polymerization and the characterization of mesoporous crosslinked polystyrene particles in the nanometer range (ca. 30 nm) are reported here. The particles have pores between 6 and 8 nm in diameter and pore volume around 0.40 cm3/g. In spite that the polymerization was not carried out at highly monomer-starved conditions, particles with narrow size distribution were obtained, which is ascribed to inter-particle hetero-coagulation at latter stages of polymerization, due to lack of enough surfactant to cover all the particles even before 45% global conversion.  相似文献   
6.
The aim is to deepen our understanding about the internationalisation–survival relationship in the case of new ventures in traditional manufacturing sectors. Hypotheses were tested through Cox’s proportional hazard regressions on a sample of 3,350 firms aged 10 years or less, from the textile-clothing and footwear industry in Spain. A vast majority of new ventures that were both established and closed down over that time are purely domestic firms. That means, a firm increases its likelihood of survival when it becomes international. The highest failure risk relates to those new ventures which are territorially agglomerated and are domestically oriented. Internationalisation is an unconditional strategy for surviving in the case of new manufacturing ventures. In addition, location and efficiency in the activity both matter when operating in international markets. Statistical tests show that an interactive effect of agglomeration and internationalisation exists, while no support for the interaction between age and internationalisation is found. Future research should investigate the trade-off between growth and survival forces to determine the optimum moment to go international and to characterise the strategic choices followed by those new ventures that survive longest.  相似文献   
7.
The use of straight vegetable oil (SVO) as biofuel has been recognized as a valid substitute of diesel fuel in the agricultural sector under specific circumstances. Its direct use reduces most of the chemical processes involved when converting it into biodiesel, thus lowering harmful emissions. This study presents the economic analysis of a self-supply farming model that uses rapeseed as its fuel base. This model addresses agricultural environmental concerns and can even minimize dependence on the fluctuating costs of diesel fuel. The use of SVO in agriculture can help reduce farmers’ vulnerability to fossil fuel prices. The economic evaluation of the model proposed in this study shows clear economic benefits of introducing rapeseed to the traditional crop rotation of wheat and barley. The key factors analyzed in this model are diesel fuel price, diesel fuel grants and crop aids. The current situation in Spain favors the use of diesel fuel in agriculture rather than rapeseed SVO due to an 8% profit difference. However, results show that changes in key factors slightly affect the profit margin, calculating a difference of only 3.7% for particular factor combinations. Combined environmental-friendly agriculture supporting policies are necessary to cover this slight profit difference to promote this biofuel.  相似文献   
8.
9.
A 66-year-old woman was admitted to our hospital complaining of abdominal pain and jaundice. Upper gastrointestinal series and computed tomography revealed pancreatic cancer. Pancreatectomy could not be performed because of portal invasion and multiple liver metastasis. Cholecystectomy, choledochojejunostomy and gastrojejunostomy were performed. The patient was treated with methotrexate (MTX) 100 mg/m2 i.v. followed one hour later with 5-fluorouracil (5-FU) 700 mg/m2. Leucovorin rescue of 10 mg po was given 24 hours after MTX administration. Treatment was repeated every 14 days. As a result, the size of a primary tumor of the pancreas was reduced (42%) on computed tomography, and the CEA level decreased to 27.8 ng/ml from 84 ng/ml. No side effects were observed. The patient continued to receive chemotherapy at our outpatient clinic for 20 months. She died of exacerbation of carcinomatous peritonitis 23 months after initial admission. Therefore, we conclude that MTX/5-FU sequential therapy seems beneficial to manage advanced pancreatic carcinoma from the viewpoint of antineoplastic activity as well as quality of life.  相似文献   
10.
Recent developments in texture classification have shown that the proper integration of texture methods from different families leads to significant improvements in terms of classification rate compared to the use of a single family of texture methods. In order to reduce the computational burden of that integration process, a selection stage is necessary. In general, a large number of feature selection techniques have been proposed. However, a specific texture feature selection must be typically applied given a particular set of texture patterns to be classified. This paper describes a new texture feature selection algorithm that is independent of specific classification problems/applications and thus must only be run once given a set of available texture methods. The proposed application-independent selection scheme has been evaluated and compared to previous proposals on both Brodatz compositions and complex real images.  相似文献   
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