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1.
Concentrations and types of airborne fungal spores and their aerodynamic sizes were studied in nine buildings with mould problems and in matched reference buildings in order to characterize the exposure in buildings with mould problems. Samples were taken with Andersen six-stage impactors in the autumn and winter. In winter, total concentrations of fungal spores in buildings with mould problems were twice those in reference buildings, even though all concentrations were quite small. In the autumn, the differences were less obvious due to the masking effect of outdoor air fungi. Also, the compositions of fungal genera differed in buildings with mould problems from that in reference buildings. The difference was most significant in the size range 2.1-4.7 μm. The size distribution of fungal spores in dwellings with mould problems skewed towards larger particles than in reference dwellings. The observed differences in size distribution indicate differences in airborne behaviour of fungal spores and, consequently, in respiratory exposure.  相似文献   
2.
In the Post Correspondence Problem (PCP) an instance (h,g)(h,g) consists of two morphisms hh and gg, and the problem is to determine whether or not there exists a nonempty word ww such that h(w)=g(w)h(w)=g(w). Here we prove that the PCP is decidable for instances with unique blocks using the decidability of the marked PCP. Also, we show that it is decidable whether an instance satisfying the uniqueness condition for continuations has an infinite solution. These results establish a new and larger class of decidable instances of the PCP, including the class of marked instances.  相似文献   
3.
The effect of austenite pancaking in the non-recrystallization regime on microstructure and texture evolution and thereby on bendability was investigated in an ultrahigh-strength strip steel with a martensitic-bainitic microstructure. The results indicate that an increase in rolling reduction (R tot) below the non-recrystallization temperature, which improves the strength and toughness properties, increases the intensities of the ~{554}〈225〉 α and ~{112}〈110〉 α texture components along the strip centerline and of the ~{112}〈111〉 α component at the surface region. Even with the highest R tot of 79 pct, the bendability along the rolling direction was good, but the preferred alignment of rod-shaped MA constituents along the rolling direction led to a dramatic decrease in the bendability transverse to the rolling direction, with severe cracking occurring even at small bending angles. The early cracking is attributed to localization of the strain in narrow shear bands. It is concluded that the Rtot value has to be limited to guarantee successful bendability.  相似文献   
4.
Antibody–drug conjugates (ADCs) are promising alternatives to naked antibodies for selective drug‐delivery applications and treatment of diseases such as cancer. Construction of ADCs relies upon site‐selective, efficient and mild conjugation technologies. The choice of a chemical linker is especially important, as it affects the overall properties of the ADC. We envisioned that hydrophilic bifunctional chemical linkers based on carbohydrates would be a useful class of derivatization agents for the construction of linker–drug conjugates and ADCs. Herein we describe the synthesis of carbohydrate‐based derivatization agents, glycolinker–drug conjugates featuring the tubulin inhibitor monomethyl auristatin E and an ADC based on an anti‐EGFR antibody. In addition, an initial in vitro cytotoxicity evaluation of the individual components and the ADC is provided against EGFR‐positive cancer cells.  相似文献   
5.
The effect of ditching of boreal forest land (W. Finland) on P and N dynamics and export was assessed using a paired catchment approach (response stream + control stream) for a 4-year study period. After the ditching operations, there was a small but significant increase in the NH4+ export, but no significant changes in the concentrations and loads of total reactive P, total non-reactive P, total organic N and NO3-. In both streams, the reactive P fraction largely followed the Fe concentrations. High input to output ratios, and thus, high retention was a typical feature of the inorganic N compounds. Total organic N and the TOC/TON ratio were positively correlated with the total organic carbon.  相似文献   
6.
Quantitative structure-activity relationships (QSARs) have proved increasingly useful for predicting the biological activities of molecules (e.g., their binding affinities to different receptors) and can be used in environmental chemistry as a preliminary tool for screening the activities of untested molecules, producing valuable information on which compounds should be tested more thoroughly with experimental affinity assays or in animals. The predictive ability of the consensus kNN QSAR method is corroborated here using a diverse set of 245 compounds, which have been assayed for their relative binding affinities to the estrogen receptor of four species: human (ER alpha and ER beta), calf, mouse, and rat. Leave-one-out cross-validation (LOO-CV) and gamma-randomization tests were applied to the QSAR models for internal validation, and separate training and test sets were used for external validation. The internal predictive abilities of the consensus models for all five data sets were convincing, with cross-validated correlation coefficients (LOO-CV q2 values) varying from 0.69 (human ER beta data) to 0.79 (human ER alpha data). The external predictive abilities were also encouraging, as the predictive r2 scores (pr-r2 values) varied from 0.62 (human ER beta data) to 0.77 (calf and mouse data). The results indicate that consensus kNN QSAR is a feasible method for rapid screening of the estrogenic activity of organic compounds.  相似文献   
7.
Smooth, 4–6-nm thick hafnium oxide films were grown by atomic layer deposition from HfI4 or HfCl4 and H2O on SiO2/Si(1 0 0) substrates at 300 °C. Non-uniform films were obtained on hydrogen-terminated Si(1 0 0). The stoichiometry of the films corresponded to that of HfO2. The films contained small amounts of residual chlorine and iodine. The films deposited on SiO2/Si(1 0 0) were amorphous, but crystallized upon annealing at 1000 °C. In order to decrease the conductivity, the HfO2 films were mixed with Al2O3, and to increase the capacitance, the films were mixed with Nb2O5. The capacitance–voltage curves of the Hf–Al–O mixture films showed hysteresis. The capacitance–voltage curves of HfO2 films and mixtures of Hf–Al–Nb–O were hysteresis free.  相似文献   
8.
Operations research is applied to analysing uncertainties in the selection of nuclear reactor types. Dynamic programming methods have been extended to account for uncertain decision factors by including in the objective function a variance-related uncertainty factor as well as expected cost values. A technique is also described for obtaining total cost probability distributions. A case study is presented which uses the method to analyze a long-term planning problem for a given electric utility system. This problem is also solved by using fuzzy programming methods.  相似文献   
9.
The celebrated architect, educator and author Juhani Pallasmaa is well-known for having forged a new understanding of perception and the experiential in architecture with his seminal book The Eyes of the Skin: Architecture and the Sensory (3rd edn, Wiley, 2012). Here he describes how ‘imagining human situations’ is at the core of architecture, relying on the interrelationship of physical space, behaviour and the capacity for mental tuning.  相似文献   
10.
The G-protein coupled receptor GPR39 is abundantly expressed in various tissues and can be activated by changes in extracellular Zn2+ in physiological concentrations. Previously, genetically modified rodent models have been able to shed some light on the physiological functions of GPR39, and more recently the utilization of novel synthetic agonists has led to the unraveling of several new functions in the variety of tissues GPR39 is expressed. Indeed, GPR39 seems to be involved in many important metabolic and endocrine functions, but also to play a part in inflammation, cardiovascular diseases, saliva secretion, bone formation, male fertility, addictive and depression disorders and cancer. These new discoveries offer opportunities for the development of novel therapeutic approaches against many diseases where efficient therapeutics are still lacking. This review focuses on Zn2+ as an endogenous ligand as well as on the novel synthetic agonists of GPR39, placing special emphasis on the recently discovered physiological functions and discusses their pharmacological potential.  相似文献   
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