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1.
2.
TR Tripi 《Canadian Metallurgical Quarterly》1997,46(11):609-614
The case of a girl with Binder syndrome (maxillonasal-dysplasia) is reported. The girl has a peculiar face due to severely depressed nasal bridge, the nasofrontal angle is absent and the nose is hypoplastic with flattened alae and nasal tip; the upper lip has a convex contour with poorly developed philtrum. The premaxillary is hypoplastic. Lateral and postero-anterior cephalometric findings are presented. 相似文献
3.
Terminal chromosome associations ("satellite associations") in ASG-banded preparations have been used to determine the number and location of staellites in the Syrian hamster (Mesocricetus auratus) and the Djungarian hamster (Phodopus sungorus). Five pairs of satellites are found in the former and four in the latter. Nucleolar organizing regions (NORs) were visualized with the Ag-AS silver precipitation technique, and their number and position corresponded exactly with the number and position of satellites in Phodopus, where positive chromosome identification can be made in the absence of banding. Numerical agreement is exact in Mesocricetus as well, and the morphology of the silver-tagged NOR-bearing chromosomes strongly suggests that corrrespondence also occurs in this species. 相似文献
4.
J Marszalek W Zhang TR Hupp C Margulies KM Carr S Cherry JM Kaguni 《Canadian Metallurgical Quarterly》1996,271(31):18535-18542
DnaA protein of Escherichia coli is a sequence-specific DNA-binding protein required for the initiation of DNA replication from the chromosomal origin, oriC. It is also required for replication of several plasmids including pSC101, F, P-1, and R6K. A collection of monoclonal antibodies to DnaA protein has been produced and the primary epitopes recognized by them have been determined. These antibodies have also been examined for the ability to inhibit activities of DNA binding, ATP binding, unwinding of oriC, and replication of both an oriC plasmid, and an M13 single-stranded DNA with a proposed hairpin structure containing a DnaA protein-binding site. Replication of the latter DNA is dependent on DnaA protein by a mechanism termed ABC priming. These studies suggest regions of DnaA protein involved in interaction with DnaB protein, and in unwinding of oriC, or low-affinity binding of ATP. 相似文献
5.
MD Kipke TR Simon SB Montgomery JB Unger EF Iversen 《Canadian Metallurgical Quarterly》1997,20(5):360-367
Sick building syndrome is the term given to a heterogeneous constellation of symptoms that affects workers in modern mechanically ventilated office buildings. Although the cause is unknown, there is evidence that the local environment of the work station is an important determinant of symptoms. In this study, investigators examined the effect of a new, individually controlled ventilation system on workers' symptoms. Investigators studied two groups of workers in one mechanically ventilated office building: (1) a control group at whose worksite no intervention was made and (2) an intervention group. The intervention consisted of installation of a device that allowed each worker control over the ventilation supplied to his or her worksite. Just before, and 4 and 16 mo after installation of this device, workers completed self-administered questionnaires regarding occurrence of symptoms. The new ventilation system resulted in higher air velocities, more variable temperatures, and higher concentrations of airborne dust and fungal spores. Four months after installation, workers with the new ventilation system reported fewer symptoms that were (a) work-related (p < .05) and that were work-related and frequent (p < .05); in addition, they reported fewer symptoms that reduced their capacity to work (p < .01). Sixteen months after installation, workers with the new device reported fewer symptoms than at baseline (although not as significantly), and they indicated that the indoor air quality improved their productivity by 11%, compared with a 4% reduction of productivity among the control group of workers (p < .001). Investigators concluded that the new ventilation system, which provided the workers with individual control over ventilation, was associated with important and sustained reduction in symptoms. 相似文献
6.
Exploration of the two‐photon excitation spectrum of fluorescent dyes at wavelengths below the range of the Ti:Sapphire laser 下载免费PDF全文
J. TRÄGÅRDH G. ROBB R. AMOR W.B. AMOS J. DEMPSTER G. McCONNELL 《Journal of microscopy》2015,259(3):210-218
We have studied the wavelength dependence of the two‐photon excitation efficiency for a number of common UV excitable fluorescent dyes; the nuclear stains DAPI, Hoechst and SYTOX Green, chitin‐ and cellulose‐staining dye Calcofluor White and Alexa Fluor 350, in the visible and near‐infrared wavelength range (540–800 nm). For several of the dyes, we observe a substantial increase in the fluorescence emission intensity for shorter excitation wavelengths than the 680 nm which is the shortest wavelength usually available for two‐photon microscopy. We also find that although the rate of photo‐bleaching increases at shorter wavelengths, it is still possible to acquire many images with higher fluorescence intensity. This is particularly useful for applications where the aim is to image the structure, rather than monitoring changes in emission intensity over extended periods of time. We measure the excitation spectrum when the dyes are used to stain biological specimens to get a more accurate representation of the spectrum of the dye in a cell environment as compared to solution‐based measurements. 相似文献
7.
K. TRÄDER 《国际可持续能源杂志》2013,32(5):281-295
In 1980, the CEC launched a call for tenders for photovoltaic pilot projects. Since mid 1984, all the relating plants are in operation. In late summer 198S, the WIP has been charged to inspect the PV plants, so as to gather information on the operational status of the systems. This inspection showed that most of the plants are working satisfactorily. Nevertheless, optimization measures are possible for many installations in the field of power management and conditioning systems, data acquisition and recording, battery management and charge controlling, loads and load matching, software, maintenance and documentation. So far, the PV modules themselves, the support structures and batteries have shown to be trouble-free components of PV systems. In order to preserve the potential of the PV plants and make good use of it, the Commission sponsors, in the frame of the current photovoltaic R & D Programme, follow-up activities on the existing installations. 相似文献
8.
Chemical and Isotopic Tracer Evaluation of Water Mixing and Evaporation in a Dammed Texas River During Drought 下载免费PDF全文
The interaction between drought and river regulation is monitored to better understand river flow mixing, evaporation and surface‐groundwater exchange in changing regional climates and in increasingly regulated waterways. This study compared Brazos River stable isotope (δ18O and δD) and electrical conductivity values with reservoir, creek and aquifer samples in the Brazos watershed, the largest watershed in Texas. The combination of tributaries, rainfall and the Brazos River Alluvium Aquifer, on the one hand, and the Lake Whitney reservoir, on the other hand, represent endmembers of dilute run‐off water and evaporated saline water, respectively. A simple isotope mixing model that uses monthly river discharge, Lake Whitney discharge, historical monthly precipitation δ18O and pan evaporation accurately reconstructs river δ18O (±0.5‰ on average). Data and isotope balance modelling support continued evaporation of 18O‐enriched Lake Whitney water as it flows downstream, although the most evaporation took place in Lake Whitney. The difference between river and precipitation δ18O, or Δ18ORIV‐PPT, here a measurement of degree of evaporation, ranged from ?0.1‰ for a small creek, to 1.7‰ for the Brazos River, to at least 2.7‰ in Lake Whitney. This study indicates that drought in regulated rivers may enhance reservoir discharge dominance in river flows during peak drought conditions when combined run‐off and baseflow dominance would be expected in a similar undammed river. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
9.
TR Kirkpatrick 《Canadian Metallurgical Quarterly》1985,31(9):5746-5755
10.
Forty subjects were administered the portable rod-and-frame test (RFT) before and after operant autonomic conditioning training or control experiences. Ten subjects were assigned to each of four groups: a heart rate conditioning group; a false heart rate feedback group; a galvanic skin-response conditioning group; and a control group. Half of the subjects in the three experimental groups were informed of the response-reinforcement contingencies, and half were not informed. Informed subjects in the conditioning groups exhibited significantly lower portable RFT scores after conditioning. The results suggest that awareness of and control over autonomic functioning may be an important determinant of RFT performance. 相似文献