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Allicin (AL) regulates the cellular redox, proliferation, viability, and cell cycle of different cells against extracellular-derived stress. This study investigated the effects of allicin treatment on porcine oocyte maturation and developmental competence. Porcine oocytes were cultured in medium supplemented with 0 (control), 0.01, 0.1, 1, 10 or 100 μM AL, respectively, during in vitro maturation (IVM). The rate of polar body emission was higher in the 0.1 AL-treated group (74.5% ± 2.3%) than in the control (68.0% ± 2.6%) (P < 0.1). After parthenogenetic activation, the rates of cleavage and blastocyst formation were significantly higher in the 0.1 AL-treated group than in the control (P < 0.05). The reactive oxygen species level at metaphase II did not significantly differ among all groups. In matured oocytes, the expression of both BAK and CASP3, and BIRC5 was significantly lower and higher, respectively, in the 0.1 AL-treated group than in the control. Similarly, the expression of BMP15 and CCNB1, and the activity of phospho-p44/42 mitogen-activated protein kinase (MAPK), significantly increased. These results indicate that supplementation of oocyte maturation medium with allicin during IVM improves the maturation of oocytes and the subsequent developmental competence of porcine oocytes.
A K-band microstrip delay line based on parasitic reduced left-handed transmission line (LHTL) with interdigital capacitors and shunt inductors is demonstrated with the aid of printed circuit board technology. The proposed delay line has ground slots under the interdigital capacitors to reduce the parasitic capacitance. The time delay of the proposed LHTLs is approximately 2.6 times larger than that of the conventional LHTLs. The input return loss of the proposed LHTL at 24 GHz is −16.9 dB and less than −10 dB from 20.5 to 26.1 GHz.
Vitamin D insufficiency is known to be related to cardiometabolic disorders; however, the associations among serum 25-hydroxyvitamin D (25(OH)D) concentration and metabolic syndrome and cardiometabolic risk factors in children and adolescents have not yet been clearly delineated. For this reason, we investigated the relationship among serum 25(OH)D concentration and metabolic syndrome and cardiometabolic risk factors among Korean adolescents.
We performed a cross-sectional analysis and used hierarchical multivariate logistic regression analysis models to adjust for confounding variables.
We used the data gathered during the 2008–2009 Korea National Health and Nutrition Examination Survey (KNHANES).
Our subjects included 1504 Korean adolescents aged 12–18 years who participated in the KNHANES.
Vitamin D insufficiency, defined as 25(OH)D concentration <50 nmol/l, was found in 75·3 % of Korean adolescents and was associated with an increased risk of the prevalence of metabolic syndrome. Waist circumference and BMI were the most closely correlated cardiometabolic components of metabolic syndrome according to serum 25(OH)D status, but no significant relationship was found between serum 25(OH)D concentration and insulin resistance or for the risks for high blood pressure, hyperglycaemia, reduced HDL-cholesterol or hypertriacylglycerolaemia, with or without adjustment for confounding variables.
Low serum 25(OH)D concentration appears to be associated with several cardiometabolic risk factors and an increased risk of the prevalence of metabolic syndrome in Korean adolescents.
Anthropogenic land use within watersheds has substantial effects on aquatic habitats and biological communities. From September 2006 to December 2008, we investigated the effects of land use on benthic macroinvertebrate communities by comparing Song Stream and Odae Stream, two adjacent mountain streams in Korea whose watersheds have different land use patterns. Song Stream is significantly disturbed by agricultural activities in the watershed, whereas Odae Stream is relatively undisturbed and is surrounded by a well-conserved forest area. Song Stream had significantly higher levels of all nutrients and sediment-related factors due to the adjacent agricultural area. As a result, Song Stream had markedly lower species community indices, such as taxa richness and abundance. In Song Stream, macroinvertebrate scrapers and predators were most adversely affected, whereas collector-gatherers became a dominant group. Based on correlation and multivariate analyses, total dissolved solids had the strongest negative relationship with macroinvertebrate assemblages, followed by electrical conductivity, total nitrogen, and pH. The proportion of cobble in stream substrate was positively related to the richness and abundance of macroinvertebrates. Our results indicate that disturbances caused by agricultural land use, particularly sand deposition, had significant adverse effects on macroinvertebrate habitats and on the biotic integrity of benthic macroinvertebrate communities.
Ndc80 (called Hec1 in human), the core component of the Ndc80 complex, is involved in regulation of both kinetochore-microtubule interactions and the spindle assembly checkpoint in mitosis; however, its role in meiosis remains unclear. Here, we report Ndc80 expression, localization, and possible functions in mouse oocyte meiosis. Ndc80 mRNA levels gradually increased during meiosis. Immunofluorescent staining showed that Ndc80 was restricted to the germinal vesicle and associated with spindle microtubules from the Pro-MI to MII stages. Ndc80 was localized on microtubules and asters in the cytoplasm after taxol treatment, while Ndc80 staining was diffuse after disruption of microtubules by nocodazole treatment, confirming its microtubule localization. Disruption of Ndc80 function by either siRNA injection or antibody injection resulted in severe chromosome misalignment, spindle disruption, and precocious polar body extrusion. Our data show a unique localization pattern of Ndc80 in mouse oocytes and suggest that Ndc80 may be required for chromosome alignment and spindle organization, and may regulate spindle checkpoint activity during mouse oocyte meiosis.
Assessment of frontal lobe impairment in amyotrophic lateral sclerosis (ALS) is a matter of great importance, since it often causes ALS patients to decrease medication and nursing compliance, thus shortening their survival time.
The frontal assessment battery (FAB) is a short and rapid method for assessing frontal executive functions. We investigated the applicability of the FAB as a screening method for assessing cognitive impairments in 61 ALS patients. Depending on the results of the FAB, we classified patients into two subgroups: FAB-normal and FAB-abnormal. We then performed additional evaluations of cognitive function using the Korean version of the mini-mental state examination (K-MMSE), a verbal fluency test (COWAT), and a neuropsychiatric inventory (NPI). Results of these tests were compared between the two groups using Mann-Whitney U-tests, and Spearman correlation analyses were used to investigate the relationships between FAB score and disease duration and severity.
Of the 61 sporadic ALS patients included in this study, 14 were classified as FAB-abnormal and 47 were classified as FAB-normal. The FAB-normal and FAB-abnormal patients performed significantly differently in all domains of the COWAT. There was no difference in behavioral disturbance, as assessed by the NPI, between the two groups. The FAB scores were found to significantly correlate with both disease duration and severity.
The FAB shows promise as a method of screening for frontal lobe dysfunction in ALS, as it is not only quick and easy, but also reliable. Additional studies should examine how FAB performance changes as ALS progresses.
The correlation of surface morphology with strain relaxation in the In0.15Ga0.85As epilayer on GaAs(100) grown by chemical beam epitaxy using unprecracked monoethylarsine has been investigated. The surface morphology of InGaAs was analyzed by atomic force microscopy as the epilayer thickness was increased from 0.025 to 1.668 μm. The changes in the surface morphology indicated that surface roughening is related to the process of strain relaxation in the film. The strain-induced shifts in the GaAs-like longitudinal optical phonon in the Raman spectrum also indicated that the strains in the InGaAs epilayer relax via step-wise process with increasing the film thickness beyond the critical thickness, which agrees well with the changes of surface mophology.
The effects of anisotropic dielectric properties of ferroelectric Ba1-xSrxTiO3 (BST) films on the characteristics of phase shifter have been studied in microwave regions at room temperature. Ferroelectric BST films with (001) and (011) orientation were epitaxially grown on (001) and (011) MgO substrates, respectively, by pulsed laser deposition method. The structures of BST films were investigated using x-ray diffraction measurement. The microwave properties of orientation engineered BST films were investigated using coplanar waveguide transmission lines that were fabricated on BST films using a thick metal layer by photolithography and etching process. The measured differential phase shift and insertion loss (S21) for (011) BST films are larger than those for (001) BST films. Dielectric constants of the ferroelectric BST films are calculated from the measured S21 using a modified conformal-mapping model.
Microwave properties of coplanar waveguide (CPW) transmission lines fabricated on high dielectric materials, such as ferroelectric Ba1−xSrxTiO3 films, are highly sensitive on the dimension and shape of electrodes. A small change in device dimension affects the total electrical length of the CPW, which may mislead the effective dielectric constant of the dielectric layer. Furthermore, extracting dielectric constant of high-k thin films from the measured microwave properties, such as S-parameters, is very difficult. The well known a modified conformal mapping method frequently exhibits an inconsistent dielectric constant for CPW on high-k materials. CPW transmission lines were fabricated on high-k thin films, ferroelectric Ba0.6Sr0.4TiO3, which were deposited by the pulsed laser deposition with partial oxygen backgrounds. A large phase shift angle of 100° at 10 GHz was observed from the CPW (gap = 4 μm, length = 3 mm) with a 40 V of dc bias, which supports that the idea of the tunable microwave device application using ferroelectrics films. The dielectric constant of the thin ferroelectric film was extracted from the dimension of the CPW (gap, width, length) and the measured S-parameters by a modified conformal mapping. However, the dielectric constant of the ferroelectric thin film calculated by a modified conformal mapping exhibits a gap dependency; dielectric constant (990 ∼ 830) decreases with increasing gap size (4 ∼ 19 μm, respectively). For comparison, dielectric properties have been extracted by extensive EM-simulation using a HFSS™ (Ansoft) with observed dimensions of CPW devices. Total phase, which is closely related with the dielectric constant of the film, is strongly affected by gap size, film thickness, and slanted angle of CPW.
The ferroelectric (Ba0.6Sr0.4)TiO3 (BST) films were prepared on (001) MgO single crystals by pulsed laser deposition. Coplanar waveguide (CPW) type phase shifters controlled by external dc bias field were fabricated on BST films using a 2 μm thick metal layer to reduce metal loss. Microwave properties of the CPW phase shifter were measured using a HP 8510C vector network analyzer from 0.1 – 20 GHz. The fabricated CPW phase shifters (8 mm long) exhibited differential phase angle of 100 ° at 10 GHz with a dc bias field of less than 80 kV/cm between center and ground conductors. Furthermore, a stable differential phase angle (102 ± 3.5 o) was observed from another CPW while changing the power of incident microwave from -10 to +30 dBm. Gap size dependent dielectric constant of the BST film was observed and a simple correction method was suggested in the paper. These results demonstrate the possible application of ferroelectric tunable devices on a high power tunable wireless telecommunication.
(001) oriented (Ba, Sr)TiO3 (BST) thin films were deposited on MgO (001) single crystal substrates by the pulsed laser deposition method. Structural properties of BST films were investigated using X-ray diffractometer. Coplanar waveguide (CPW) device based on BST/MgO layer structure was fabricated by dc sputtering deposition, photolithography and etching process. To study the geometrical factor dependent microwave performance of the CPW phase shifter based on (001) oriented BST film, the CPW devices having various gap and width were fabricated. The microwave dielectric properties of BST CPW phase shifter devices were examined by calculating the scattering parameter obtained using a HP 8510C vector network analyzer with the frequency range 0.5 ∼ 20 GHz at room temperature under the dc bias field of 0 ∼ 40V. The measured return loss and insertion loss at 10 GHz with no dc bias were about -12 ∼ -4 dB and -14 ∼ -3 dB, respectively, which mainly depended on the impedances of the CPW transmission lines. The measured differential phase shift values were about 20 ° ∼ 140 ° at 10 GHz with 40 V dc bias variations, which depended on the gap size.
We have fabricated the nano-floating gate memory with the TiSi2 and WSi2 nanocrystals embedded in the dielectrics. The TiSi2 and WSi2 nanocrystals were created by using sputtering and rapidly thermal annealing system, and then their morphologies were investigated by transmission electron microscopy. These nanocrystals have a spherical shape with an average diameter of 2-5 nm. The electrical properties of the nano-floating gate memory with TiSi2 and WSi2 nanocrystals were characterized by capacitance-voltage (C-V) hysteresis curve, memory speed and retention. The flat-band voltage shifts of the TiSi2 and WSi2 nanocrystals capacitors obtained appeared up to 4.23 V and 4.37 V, respectively. Their flat-band voltage shifts were maintained up to 1.6 V and 1 V after 1 hr.
Perimesencephalic subarachnoid hemorrhage (PSH) is a relatively benign clinical entity with a low risk of recurrent bleeding. The precise etiology of PSH has not yet been determined. We report here three cases of PSH with clinical and radiological features that support a venous system as a cause.
The first patient, a 72-year-old woman, had PSH and venous hemorrhagic infarct in the left thalamus on non-contrast CT. Subsequent cerebral angiography revealed widespread thrombosis in the cerebral venous system, a potential cause for reflux overflow hemorrhage. The second patient, a 55-year-old man with an established diagnosis of neuro-Behçet's disease, a well-known cause for cerebral venulitis, presented with PSH one year later. The third patient, a 39-year-old female, with incomplete Behçet's disease was admitted with PSH.
Current concepts on the anatomic origin and the possible pathophysiologic mechanism leading to PSH are discussed. The underlying pathological conditions in the venous system in our cases provide theoretical clues to the anatomic origin of PSH in general.
To enhance Pt utilization in the fuel-cell electrode by microscopically controlling the distribution of liquid electrolytes around Pt catalysts, the amphiphilic surfactant tergitol phosphate was synthesized and introduced into the fuel-cell electrode. The chemical structure of the surfactant was determined by 1H-nuclear magnetic resonance, and its adsorption property on Pt–C catalyst was ascertained by Fourier transform infrared analysis. The electrode into which the amphiphilic surfactants were incorporated showed improved performance, and especially the amphiphilic surfactant with polyethylene oxide, NPE10-OPO(OH)2, produced higher cell performance.
The incidence of restless legs syndrome (RLS) is presumed to be higher among people with schizophrenia who take antipsychotic medication, most of which blocks the dopamine D2 receptor. The purpose of this study was to determine whether the G-protein β3 subunit (GNB3) C825T polymorphism is associated with antipsychotic-induced RLS in schizophrenia.
We examined 178 Korean patients with schizophrenia. All of the subjects were evaluated using the diagnostic criteria of the International Restless Legs Syndrome Study Group and the International Restless Legs Scale. Genotyping was performed for the C825T polymorphism in the GNB3 gene.
The genotype distribution did not differ significantly between antipsychotic-induced RLS patients and patients who had no-RLS symptoms (χ2 = 4.30, p = 0.116). The genotypes of the C825T single-nucleotide polymorphism (SNP) were classified into two groups: C+ (CC and CT genotypes) and C– (TT genotype). The presence of the C allele (C+) was associated with an increased likelihood of RLS (χ2 = 4.14, p = 0.042; odds ratio = 2.56, 95% confidence interval = 1.02–6.47).
These results suggest that the GNB3 C825T SNP is associated with RLS in schizophrenia. However, confirming this association requires future larger scale studies in which the effects of medication are strictly controlled.
The Na+-K+-2Cl- cotransporter (NKCC1) is responsible for ion transport across the secretory and absorptive epithelia, the regulation of cell volume, and possibly the modulation of cell growth and development. It has been reported that a variety of cells, including osteoblasts, contain this cotransporter. In this study, the physiological role of NKCC1 in osteoclastogenesis was exploited in a co-culture system. Bumetanide, a specific inhibitor of NKCC1, reduced the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells. In order to investigate the mechanism by which bumetanide inhibits osteoclastogenesis, the mRNA expressions of the receptor activator of nuclear factor (NF)-κB ligand (RANKL) and osteoprotegerin (OPG) were analysed by RT-PCR. Exposure of osteoblastic cells to a medium containing 1 µM bumetanide reduced RANKL mRNA expression induced by 10 nM 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3, in a dose-dependent manner. In addition, RANKL expression was also analysed with enzyme-linked immunosorbant assay (ELISA) using anti-RANKL antibody. The expression of RANKL was decreased with the increase of bumetanide concentration. In contrast, the expression of OPG mRNA, a novel tumour necrosis factor (TNF) receptor family member was increased in the presence of bumetanide. These results imply that bumetanide inhibits osteoclast differentiation by reducing the RANKL/OPG ratio in osteoblastic cells. However, no significant difference in M-CSF mRNA expression was observed when bumetanide was added. Also, we found that the phosphorylation of c-Jun NH2-terminal kinase (JNK), which regulates the activity of various transcriptional factors, was reduced by bumetanide treatment. Conclusively, these findings suggest that NKCC1 in osteoblasts has a pivotal role in 1α,25(OH)2D3-induced osteoclastogenesis partly via the phosphorylation of JNK. Experimental Physiology (2003) 88.5, 569-574.
It is shown that an immersion of n dimensional compact oriented manifold without boundary into the n+1 dimensional Euclidean space, hyperbolic space or open half sphere is a totally umbilic immersion if one of the mean curvature function H_l does not vanish and the ratio H_k/H_l is constant, 1\leq k, l \leq n, k\ne l.
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