Probe modeling for millimeter-wave integrated-circuit horn antennas

Integrated-circuit probe-excited horn-antenna arrays etched in silicon are well developed. They are a very promising class of antenna arrays for milli-meter and submillimeter applications. Further development of this technology involves integrating mixers and amplifiers into the antenna arrays. In an effort to develop an antenna-mixer array based on the existing technology, various antenna probes inside the pyramidal horns have been examined on scaled model-horns at the microwave frequencies. In this paper, modeling results and design principles of these antenna probes have been presented, which include the resonant impedance, the operating frequency, and the bandwidth of the horn antennas. These measurement results provide a guideline in designing probes for millimeter/submillimeter-wave integrated-circuit horn-antenna-mixer arrays

Gene and protein expression of Transforming growth factor Β 2 gene during murine primary palatogenesis

The molecular mechanisms by which the primordia of the midface grow and fuse to form the primary palate are not well characterized. This is in spite of the fact that failure of growth and/or fusion of these facial primordia leads to the common human craniofacial birth defects, clefts of the lip with or without clefts of the palate. Members of the transforming growth factor Β ( Tgf Β) superfamily have been shown to play critical roles during craniofacial development. Specifically, the role of Tgf Β -3 in mediating the fusion of the embryonic secondary palatal shelves is well documented. In a screen for genes expressed during fusion of the murine midfacial processes, Tgf Β 2 was identified as a gene differentially expressed during fusion of the lateral and medial nasal processes. The objective of our study was to analyze the spatial and temporal expression of Tgf Β 2 during critical stages of midfacial morphogenesis at both the transcript and protein levels. We also compared the pattern of expression of Tgf Β 2 with that of Bmp4 , a gene shown previously to be involved in mediating the fusion process in the midface. Our results showed Tgf Β 2 expression in a very restrictive area of the epithelial layer along the borders of the midfacial primordia, in a pattern very similar to that of Bmp4 . The highly restrictive and spatial and temporal pattern of expression of Tgf Β 2 implicates its role in mediating the fusion of the midfacial processes, possibly through interacting with Bmp4 in the regulation of apoptosis and/or epithelial–mesenchymal transformation. A greater understanding of the role of this gene will clarify how the normal midface grows and the mechanisms behind cleft development.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72512/1/j.1432-0436.2005.00022.x.pd

Interleukin-1 receptor inhibition reduces stroke size in a murine model of sickle cell disease

Sickle cell disease (SCD) is associated with chronic hemolytic anemia and a heightened inflammatory state. The causal role of inflammatory pathways in stroke associated with SCD is unclear. Therefore, the hypothesis that deletion of the non-hematopoietic interleukin-1 receptor (IL-1R) pool may be beneficial in SCD was pursued. Since potential deleterious effects of IL-1R signaling in SCD could be mediated via downstream production of interleukin-6 (IL-6), the role of the non-hematopoietic IL-6 pool was also addressed. Bone marrow transplantation (BMT) from SCD to wild-type (WT) recipient mice was used to generate SCD mice (Wt,SCDbmt). To generate mice with non-hematopoietic deficiency of IL-1R or IL-6, SCD marrow was transplanted into IL-1R deficient (IL1R-/-,SCDbmt) or IL-6 deficient recipients (IL6-/-,SCDbmt). Blood counts, reticulocytes, soluble E-selectin (Esel), and IL-6 levels were analyzed 14-15 weeks post-BMT. Ischemic stroke was induced by middle cerebral artery (MCA) photothrombosis at 16 weeks post-BMT. A separate group of Wt,SCDbmt mice was given the IL-1R inhibitor, anakinra, following stroke induction. Seventy-two hours after MCA occlusion, stroke volume was assessed by staining brain sections with 2,3,5-triphenyltetrazolium chloride. Formalin-fixed brain sections were also stained for macrophages with MAC3, for endothelial activation with ICAM-1, and for loss of blood brain barrier (BBB) integrity with fibrin(ogen) staining. All SCD mice generated by BMT were anemic and the severity of anemia was not different between Wt,SCDbmt, IL1R-/-,SCDbmt, and IL6-/-,SCDbmt mice. Three days following MCA occlusion, stroke volume was significantly reduced in IL1R-/-,SCDbmt mice compared to Wt,SCDbmt mice and IL6-/-,SCDbmt mice. Plasma levels of sE-sel were lower in IL1R-/-,SCDbmt compared to Wt,SCDbmt and IL-6-/-,SCDbmt mice. Post-stroke treatment of Wt,SCDbmt mice with anakinra decreased stroke size, leukocyte infiltration, ICAM-1 expression, and fibrin(ogen) accumulation compared to vehicle-treated mice. Deficiency of non-hematopoietic IL-1R or treatment with an IL-1R antagonist is sufficient to confer protection against the increased stroke size associated with SCD. These effects of IL1R deficiency are associated with reduced endothelial activation, leukocyte infiltration, and blood brain barrier disruption, and are independent of non-hematopoietic IL-6 signaling

Adding Chinese Herbal Medicine to Routine Care is Associated With a Lower Risk of Rheumatoid Arthritis Among Patients With Asthma: A Population-Based Retrospective Cohort Study

Objective: Due to the shared pathogenesis of asthma and rheumatoid arthritis (RA), patients with asthma were found to have a higher risk of RA. While the benefits and safety of Chinese herbal medicine (CHM) for asthma have been reported, the scientific evidence regarding its effect on RA is limited. This longitudinal cohort study aimed to determine the relation between CHM use and RA risk in patients with asthma. Methods: Using the nationwide claims data, we enrolled 33,963 patients 20–80 years of age who were newly diagnosed with asthma and simultaneously free of RA between 2000 and 2007. From this sample, we utilized propensity score matching to create sets of participants as treatment and control groups, which comprised 13,440 CHM users and 13,440 non-CHM users. The incidence rate and hazard ratio (HR) for RA between the two groups were estimated at the end of 2013. A Cox proportional hazards model was constructed to examine the impact of the CHM use on the risk of RA. Results: The cumulative incidence of RA was substantially lower in the CHM user group. In the follow-up period, 214 patients in the CHM user group (1.92 per 1,000 person-years) and 359 patients in the non-CHM user group (2.92 per 1,000 person-years) developed RA (adjusted HR = 0.63, 95% confidence interval: 0.54–0.75). Of the commonly-prescribed formulae, nine CHM products were associated with a lower RA risk: Xiao-Qing-Long-Tang, Ma-Xing-Gan-Shi-Tang, Ding-Chuan-Tang, Xin-Yi-Qing-Fei-Tang, Bei Mu, Jie Geng, Xing Ren, Da Huang, and San Chi. Conclusion: This study found that patients with asthma who received CHM treatment, in addition to the conventional therapy, had a lower risk of RA. Use of CHM treatment may be integrated into conventional therapy to reduce subsequent RA risk among asthma patients

Paradoxical protection from atherosclerosis and thrombosis in a mouse model of sickle cell disease

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98139/1/bjh12342.pd

Gain-assisted superluminal light propagation via incoherent pump field

We investigate the dispersion and the absorption properties of a weak probe field in a three-level Lambda-type atomic system. We use just an incoherent field for controlling the group velocity of light. It is shown that the slope of dispersion changes from positive to negative just with changing the intensity of the indirect incoherent pumping field. Gain-assisted superluminal light propagation appears in this system. No laser field is used in the pumping processes

Association of ORAI1 Haplotypes with the Risk of HLA-B27 Positive Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic inflammation of the sacroiliac joints, spine and peripheral joints. The aetiology of ankylosing spondylitis is still unclear. Previous studies have indicated that genetics factors such as human leukocyte antigen HLA-B27 associates to AS susceptibility. We carried out a case-control study to determine whether the genetic polymorphisms of ORAI1 gene, a major component of store-operated calcium channels that involved the regulation of immune system, is a susceptibility factor to AS in a Taiwanese population. We enrolled 361 AS patients fulfilled the modified New York criteria and 379 controls from community. Five tagging single nucleotides polymorphisms (tSNPs) at ORAI1 were selected from the data of Han Chinese population in HapMap project. Clinical statuses of AS were assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and Bath Ankylosing Spondylitis Global Index (BAS-G). Our results indicated that subjects carrying the minor allele homozygote (CC) of the promoter SNP rs12313273 or TT homozygote of the SNP rs7135617 had an increased risk of HLA-B27 positive AS. The minor allele C of 3′UTR SNP rs712853 exerted a protective effect to HLA-B27 positive AS. Furthermore, the rs12313273/rs7135617 pairwise allele analysis found that C-G (OR 1.69, 95% CI 1.27, 2.25; p = 0.0003) and T-T (OR 1.75, 95% CI 1.36, 2.27; p<0.0001) haplotypes had a significantly association with the risk of HLA-B27-positive AS in comparison with the T-G carriers. This is the first study that indicate haplotypes of ORAI1 (rs12313273 and rs7135617) are associated with the risk of HLA-B27 positive AS

Thin-film power-density meter for millimeter wavelengths

A quasi-optical power density meter for millimeter and submillimeter wavelengths has been developed. The device is a 2-cm^2 thin-film bismuth bolometer deposited on a mylar membrane. The resistance responsivity is 150 Ω/W, and the time constant is 1 min. The meter is calibrated at DC. The bolometer is much thinner than a wavelength, and can thus be modeled as a lumped resistance in a transmission-line equivalent circuit. The absorption coefficient is 0.5 for 189-Ω/square film. The power-density meter has been used to measure absolute power densities for millimeter-wave antenna efficiency measurements. Absolute power densities of 0.5 mW/cm^2 have been measured to an estimated accuracy of 5%

Identification of the bulk pairing symmetry in high-temperature superconductors: Evidence for an extended s-wave with eight line nodes

we identify the intrinsic bulk pairing symmetry for both electron and hole-doped cuprates from the existing bulk- and nearly bulk-sensitive experimental results such as magnetic penetration depth, Raman scattering, single-particle tunneling, Andreev reflection, nonlinear Meissner effect, neutron scattering, thermal conductivity, specific heat, and angle-resolved photoemission spectroscopy. These experiments consistently show that the dominant bulk pairing symmetry in hole-doped cuprates is of extended s-wave with eight line nodes, and of anisotropic s-wave in electron-doped cuprates. The proposed pairing symmetries do not contradict some surface- and phase-sensitive experiments which show a predominant d-wave pairing symmetry at the degraded surfaces. We also quantitatively explain the phase-sensitive experiments along the c-axis for both Bi_{2}Sr_{2}CaCu_{2}O_{8+y} and YBa_{2}Cu_{3}O_{7-y}.Comment: 11 pages, 9 figure