On the frequency response of Multimode fibers Siuzdak, J.; Maksymiuk, L.; Stepniak, G. ...
2009 IFIP International Conference on Wireless and Optical Communications Networks,
2009-April
Conference Proceeding
Frequency response of Multimode (MM) fibers beyond the baseband is studied both theoretically and experimentally. It is shown that in the absence of mode group mixing there are relative flat ...passbands suitable for transmission in such fibers if the number of mode groups propagating is not too large. Such conditions are usually met for typical contemporary graded index (GI) silica fibers. It is also proved that the passbands width is related to the baseband width. Moreover, the 1300 nm window is the most suitable for transmission due to small chromatic dispersion and reduced number of mode groups propagating.
Frequency response of Multimode (MM) fibers beyond the baseband is studied both theoretically and experimentally. It is shown that in the absence of mode group mixing there are relative flat ...passbands suitable for transmission in such fibers if the number of mode groups propagating is not too large. Such conditions are usually met for typical contemporary graded index (GI) silica fibers. It is also proved that the passbands width is related to the baseband width. Moreover, the 1300 nm window is the most suitable for transmission due to small chromatic dispersion and reduced number of mode groups propagating.
Modal noise in cascaded multimode splitters Siuzdak, J.; Sadkowska, A.; Maksymiuk, L. ...
2008 Asia Optical Fiber Communication & Optoelectronic Exposition & Conference,
2008-Oct.
Conference Proceeding
The `low frequency' modal noise was measured at the output of cascaded 2x2 multimode splitters. For high split ratios the measured values of signal-to-modal noise ratio were too low for data ...transmission.
In this paper, operation of a cost-effective, two channel mode group diversity multiplexing system is demonstrated. The system works without use of single mode fiber components and with both step and ...graded index multimode fibers.
Abstract Herbivorous insects alter biogeochemical cycling within forests, but the magnitude of these impacts, their global variation, and drivers of this variation remain poorly understood. To ...address this knowledge gap and help improve biogeochemical models, we established a global network of 74 plots within 40 mature, undisturbed broadleaved forests. We analyzed freshly senesced and green leaves for carbon, nitrogen, phosphorus and silica concentrations, foliar production and herbivory, and stand-level nutrient fluxes. We show more nutrient release by insect herbivores at non-outbreak levels in tropical forests than temperate and boreal forests, that these fluxes increase strongly with mean annual temperature, and that they exceed atmospheric deposition inputs in some localities. Thus, background levels of insect herbivory are sufficiently large to both alter ecosystem element cycling and influence terrestrial carbon cycling. Further, climate can affect interactions between natural populations of plants and herbivores with important consequences for global biogeochemical cycles across broadleaved forests.
Abstract
PIGT
is one of over 29 glycosylphosphatidylinositol biosynthesis defect genes. Mutations cause genetically determined disorders characterized mainly by epilepsy with fever‐sensitivity, ...central hypotonia, psychomotor delay and congenital malformations. The disease is known as multiple congenital anomalies‐hypotonia‐seizures syndrome 3 (MCAHS3) or glycosylphosphatidylinositol biosynthesis defect‐7. Twenty‐eight cases have been reported until today. We present seven novel Polish patients, all harboring 1582G>A variant in a homozygous or compound heterozygous state which seems to cause a milder phenotype of the disease.
PIGT is one of over 29 glycosylphosphatidylinositol biosynthesis defect genes. Mutations cause genetically determined disorders characterized mainly by epilepsy with fever‐sensitivity, central ...hypotonia, psychomotor delay and congenital malformations. The disease is known as multiple congenital anomalies‐hypotonia‐seizures syndrome 3 (MCAHS3) or glycosylphosphatidylinositol biosynthesis defect‐7. Twenty‐eight cases have been reported until today. We present seven novel Polish patients, all harboring 1582G>A variant in a homozygous or compound heterozygous state which seems to cause a milder phenotype of the disease.
In 2007, a multifaceted syndrome, associated with anti-NMDA receptor autoantibodies (NMDAR-AB) of immunoglobulin-G isotype, has been described, which variably consists of psychosis, epilepsy, ...cognitive decline and extrapyramidal symptoms. Prevalence and significance of NMDAR-AB in complex neuropsychiatric disease versus health, however, have remained unclear. We tested sera of 2817 subjects (1325 healthy, 1081 schizophrenic, 263 Parkinson and 148 affective-disorder subjects) for presence of NMDAR-AB, conducted a genome-wide genetic association study, comparing AB carriers versus non-carriers, and assessed their influenza AB status. For mechanistic insight and documentation of AB functionality, in vivo experiments involving mice with deficient blood-brain barrier (ApoE(-/-)) and in vitro endocytosis assays in primary cortical neurons were performed. In 10.5% of subjects, NMDAR-AB (NR1 subunit) of any immunoglobulin isotype were detected, with no difference in seroprevalence, titer or in vitro functionality between patients and healthy controls. Administration of extracted human serum to mice influenced basal and MK-801-induced activity in the open field only in ApoE(-/-) mice injected with NMDAR-AB-positive serum but not in respective controls. Seropositive schizophrenic patients with a history of neurotrauma or birth complications, indicating an at least temporarily compromised blood-brain barrier, had more neurological abnormalities than seronegative patients with comparable history. A common genetic variant (rs524991, P=6.15E-08) as well as past influenza A (P=0.024) or B (P=0.006) infection were identified as predisposing factors for NMDAR-AB seropositivity. The >10% overall seroprevalence of NMDAR-AB of both healthy individuals and patients is unexpectedly high. Clinical significance, however, apparently depends on association with past or present perturbations of blood-brain barrier function.
Properly regulated intercellular adhesion is critical for normal development of all metazoan organisms. Adherens junctions play an especially prominent role in development because they link the ...adhesive function of cadherin-catenin protein complexes to the dynamic forces of the actin cytoskeleton, which helps to orchestrate a spatially confined and very dynamic assembly of intercellular connections. Intriguingly, in addition to maintaining intercellular adhesion, cadherin-catenin proteins are linked to several major developmental signaling pathways crucial for normal morphogenesis. In this article we will highlight the key genetic studies that uncovered the role of cadherin-catenin proteins in vertebrate development and discuss the potential role of these proteins as molecular biosensors of external cellular microenvironment that may spatially confine signaling molecules and polarity cues to orchestrate cellular behavior throughout the complex process of normal morphogenesis.
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