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71.
Solar Cells: Corrugation Architecture Enabled Ultraflexible Wafer‐Scale High‐Efficiency Monocrystalline Silicon Solar Cell (Adv. Energy Mater. 12/2018) 下载免费PDF全文
72.
73.
A novel confidence interval estimator is proposed for the risk difference in noninferiority binomial trials. The proposed confidence interval, which is dependent on the prespecified noninferiority margin, is consistent with an exact unconditional test that preserves the type-I error and has improved power, particularly for smaller sample sizes, compared to the confidence interval by Chan and Zhang. The improved performance of the proposed confidence interval is theoretically justified and demonstrated with simulations and examples. An R package is also distributed that implements the proposed methods along with other confidence interval estimators. 相似文献
74.
El-Temtamy Seham Farahat Laila el-din Azza Nour Gaber Ahmed 《Applied microbiology and biotechnology》1982,15(3):156-160
Summary The rheological properties of yeast (Baker's yeast) suspensions in water and in water-methanol-electrolyte solutions have been investigated using a Fann V.G. concentric cylinder viscometer. The resulted rheograms could be described by the power law model for non-Newtonian fluids with the flow behaviour index n<1 indicating pseudo-plastic behaviour. This flow behaviour index was constant under all operating conditions while the consistancy index k increased exponentially with increasing wet yeast volume fraction. The addition of methanol and electrolytes had a negligible effect on the rheological properties. Changing the pH of the suspension acidic to lowered the apparent viscosities. 相似文献
75.
S. A. El-Temtamy S. A. Khalil A. A. Nour El-Din A. Gaber 《Applied microbiology and biotechnology》1985,21(1-2):65-68
Summary Liquid-phase axial mixing coefficients were evaluated in a 0.15 m x 2.0 m batch bubble column containing water and yeast-in-water suspensions of different concentrations. Air superficial velocities ranged from 0 to 0.06 m/s. Axial mixing coefficients were calculated from the residence time distribution to an NaCl tracer pulse using the Ohki and Inuoe model. No specific variations in the calculated coefficients were observed to result from the presence of yeast cells. There was fair agreement between the data thus obtained and the only available data on mixing in non-Newtonian CMC solution.Nomenclature
C
E
equilibrium tracer concentration g/l
-
C
tracer concentration at time t g/l
- dh
sparger hole diameter m
-
D
t
tube diameter m
-
D
z
axial mixing coefficient m2/s
- g
acceleration of gravity m/s2
-
H
B
bubbling layer heigh m
-
L
longitudinal dustance between tracer injection and detection points m
-
n
1,2,6 Eq. (3)
-
t
time s
- Ug
gas superficial velocity m/s
- Ut
liquid superficial velocity m/s
-
V
r
bubble relative velocity =
m/s
-
V
t
Linear relative velocity
m/s
-
z
axial distance m
Greek c
wet cell volume farction
- g
gas holdup
-
l
liquid holdup
-
l
viscosity of the liquid phase Pa/s
-
l
density of liquid or continuous phase g/ml 相似文献
76.
BACKGROUND: Well-differentiated papillary mesothelioma (WDPM) is an uncommon subtype of mesothelioma that typically occurs in the peritoneum of women without a history of asbestos exposure and usually follows an indolent clinical course. Fine needle aspiration (FNA) of this type of tumor has rarely been reported. CASE: A 64-year-old woman with 11-year history of colon cancer and an adrenal nodule was found, on abdominal computed tomography, to have a mass in the right lobe of the liver. Aspirates of the mass were composed of abundant, tight, papillary groups, monolayered, pavementlike sheets; and scattered single cells with minimal atypia. The cell block showed a predominantly papillary growth pattern and a single layer of bland, cuboidal to flattened covering cells with stout, fibrovascular cores containing clusters of foamy histiocytes. Tumor cells in the focal tubulopapillary and solid areas were mingled with inflammatory cells and showed slightly more atypia than did the cells covering the papillae. The differential diagnoses were intrahepatic papillary neoplasm, including well-differentiated mesothelioma and metastatic low grade papillary serous carcinoma. At surgery the tumor was found to be a pedunculated peritoneal mass that arose from the posterior surface of the right lobe of the liver. The mesothelial origin of the tumor was confirmed by both immunoperoxidase study and electron microscopic examination, which demonstrated long, slender, branching microvilli. CONCLUSION: Familiarity with the cytomorphologic features and clinical presentation of WDPM, knowledge of the exact anatomic location and consideration of the appropriate differential diagnosis combined with ancillary studies are the keys to an accurate diagnosis. 相似文献
77.
78.
Ehab Salama Ghada Nour Eldeen Mazen Abdel Rasheed Sahar Abdel Atti Amr Elnoury Tamer Taha Osama Azmy 《Journal of Genetic Engineering and Biotechnology》2018,16(1):63-69
Endometriosis is a common chronic gynecological disorder defined as the presence of ectopic functional endometrial tissues, outside uterine cavity, primarily on the pelvic peritoneum and the ovaries. Several studies revealed a correlation between aberrant stem-cell activity in the endometrium and endometriosis. Yet the molecular and cellular behaviors of mesnchymal stem cells in development of endometriosis are hampered by lack of invitro experiments. Our aim was to explore morphological and molecular changes associated with mesenchymal stem cells (MSCs) exposition to serum derived from women with severe endometriosis. Two cell cultures of MSCs isolated from endometrial tissues of two endometriosis-free women. Each cell culture was treated individually with the serum of women with endometriosis (experimental group/n =?7), and serum of women without endometriosis (control group/ n = 4) for 14?days. Quantitative Real-Time PCR was performed later to reveal expression of OCT-4, CDH1 and CDH2, STAT3 and SOX2 genes. Morphologically, cells showed no significant changes. However from molecular point of view, we found increased expression in OCT-4, CDH1 and CDH2. For STAT3 and SOX2 we did not find a significant difference. This study shows that endometriosis serum induced molecular changes in human endometrial MSCs (EnMSCs) that might be related to altered cell behavior which may be a step in differentiation that may be completed invivo by other factors to complete the process of transition. Further researches are needed for optimization to reach differentiation. 相似文献
79.
D J Moellenbeck M L Peters J W Bing J R Rouse L S Higgins L Sims T Nevshemal L Marshall R T Ellis P G Bystrak B A Lang J L Stewart K Kouba V Sondag V Gustafson K Nour D Xu J Swenson J Zhang T Czapla G Schwab S Jayne B A Stockhoff K Narva H E Schnepf S J Stelman C Poutre M Koziel N Duck 《Nature biotechnology》2001,19(7):668-672
Field tests of corn co-expressing two new delta-endotoxins from Bacillus thuringiensis (Bt) have demonstrated protection from root damage by western corn rootworm (Diabrotica virgifera virgifera LeConte). The level of protection exceeds that provided by chemical insecticides. In the bacterium, these proteins form crystals during the sporulation phase of the growth cycle, are encoded by a single operon, and have molecular masses of 14 kDa and 44 kDa. Corn rootworm larvae fed on corn roots expressing the proteins showed histopathological symptoms in the midgut epithelium. 相似文献
80.
Ranad?Shaheen Amal?Hashem Ghada?M.?H.?Abdel-Salam Fatima?Al-Fadhli Nour?Ewida Fowzan?S.?AlkurayaEmail author 《Human genetics》2016,135(10):1191-1197
Primary microcephaly is a clinical phenotype in which the head circumference is significantly reduced at birth due to abnormal brain development, primarily at the cortical level. Despite the marked genetic heterogeneity, most primary microcephaly-linked genes converge on mitosis regulation. Two consanguineous families segregating the phenotype of severe primary microcephaly, spasticity and failure to thrive had overlapping autozygomes in which exome sequencing identified homozygous splicing variants in CIT that segregate with the phenotype within each family. CIT encodes citron, an effector of the Rho signaling that is required for cytokinesis specifically in proliferating neuroprogenitors, as well as for postnatal brain development. In agreement with the critical role assigned to the kinase domain in effecting these biological roles, we show that both splicing variants predict variable disruption of this domain. The striking phenotypic overlap between CIT-mutated individuals and the knockout mice and rats that are specifically deficient in the kinase domain supports the proposed causal link between CIT mutation and primary microcephaly in humans. 相似文献