A study of the Haor areas of Sylhet-Mymensing districts with ERTS imageries (winter crop estimation)

There are no author-identified significant results in this report

Heterogeneous Relational Databases for a Grid-enabled Analysis Environment

Grid based systems require a database access mechanism that can provide seamless homogeneous access to the requested data through a virtual data access system, i.e. a system which can take care of tracking the data that is stored in geographically distributed heterogeneous databases. This system should provide an integrated view of the data that is stored in the different repositories by using a virtual data access mechanism, i.e. a mechanism which can hide the heterogeneity of the backend databases from the client applications. This paper focuses on accessing data stored in disparate relational databases through a web service interface, and exploits the features of a Data Warehouse and Data Marts. We present a middleware that enables applications to access data stored in geographically distributed relational databases without being aware of their physical locations and underlying schema. A web service interface is provided to enable applications to access this middleware in a language and platform independent way. A prototype implementation was created based on Clarens [4], Unity [7] and POOL [8]. This ability to access the data stored in the distributed relational databases transparently is likely to be a very powerful one for Grid users, especially the scientific community wishing to collate and analyze data distributed over the Grid

Lmo4 Establishes Rostral Motor Cortex Projection Neuron Subtype Diversity

The mammalian neocortex is parcellated into anatomically and functionally distinct areas. The establishment of area-specific neuronal diversity and circuit connectivity enables distinct neocortical regions to control diverse and specialized functional outputs, yet underlying molecular controls remain largely unknown. Here, we identify a central role for the transcriptional regulator Lim-only 4 (Lmo4) in establishing the diversity of neuronal subtypes within rostral mouse motor cortex, where projection neurons have particularly diverse and multi-projection connectivity compared with caudal motor cortex. In rostral motor cortex, we report that both subcerebral projection neurons (SCPN), which send projections away from the cerebrum, and callosal projection neurons (CPN), which send projections to contralateral cortex, express Lmo4, whereas more caudal SCPN and CPN do not. Lmo4-expressing SCPN and CPN populations are comprised of multiple hodologically distinct subtypes. SCPN in rostral layer Va project largely to brainstem, whereas SCPN in layer Vb project largely to spinal cord, and a subset of both rostral SCPN and CPN sends second ipsilateral caudal (backward) projections in addition to primary projections. Without Lmo4 function, the molecular identity of neurons in rostral motor cortex is disrupted and more homogenous, rostral layer Va SCPN aberrantly project to the spinal cord, and many dual-projection SCPN and CPN fail to send a second backward projection. These molecular and hodological disruptions result in greater overall homogeneity of motor cortex output. Together, these results identify Lmo4 as a central developmental control over the diversity of motor cortex projection neuron subpopulations, establishing their area-specific identity and specialized connectivity.Stem Cell and Regenerative Biolog

Functionalized Multi-Walled Carbon Nanotube-Reinforced Epoxy-Composites: Electrical And Mechanical Characterization

Carbon nanotubes (CNTs) got great attention because of their interesting physical and mechanical properties. Due to these interesting properties observed at the nanoscale have motivated scientific community to utilize CNTs as reinforcement in composite materials. In the present study, different CNTs and epoxy nano-composites with different wt% (1, 2, 3, and 4%) of f-MWCNTs were prepared and their surface morphology and orientation has been investigated in detail. Further, the surface investigation, electrical and mechanical tests were carried out on CNTs-filled and unfilled epoxy at maximum sonication time 30 minute to identify the loading effect on the properties of the materials. Experimental results depicts well dispersion of f-MWCNTs, significant improvement that the resistivity of pure epoxy decreased from 108 .m to average value 103 .m with 1, 2, 3, and 4wt% f-MWCNTs. The 4.5wt% CNTs/epoxy was attributed to poor dispersion of f-MWCNTs in the nanocomposte. The hardness of nanocomposite loading 1, 2, 3, 4wt% of CNTs, increased 20.7%, 23.02%, 25.62%, 29.09% respectively as compared to pure epoxy. We believe that our strategy for obtaining CNT–reinforced epoxy nanocomposites is a very promising technology and will open a new doors in fields of aviation, aerospace, marine and sporting goods

Last-male sperm precedence in Rhynchophorus ferrugineus (Olivier): observations in laboratory mating experiments with irradiated males

The Red PalmWeevil (RPW)Rhynchophorus ferrugineus(Olivier 1790) is an invasive pest from southeastern Asia and Melanesia that in the last 30 years has spread widely in the Middle East and Mediterranean Basin. Its stem-boring larvae cause great damage to several palm species of the Arecaceae family, many of which are economically important for agricultural and ornamental purposes. Therefore, great attention has recently been focused in studying this species to identify sustainable and effective eradication strategies, such as sterile insect technique (SIT). The rapid spread of RPW is associated with its high reproductive success. To evaluate the suitability of a SIT strategy, particular physiological and behavioral aspects of RPW reproduction, such as the presence of polyandry and post-copulatory sperm selection mechanisms, were investigated. To determine paternity of progeny from multiply mated females, double-crossing experiments were carried out confining individual females with either a wild-type male or a γ-irradiated male (Co-60). Fecundity and fertility of females were scored to evaluate post-copulatory sperm selection. Results showed that progeny were almost exclusively produced by the sperm of the second male, suggesting that a last-male sperm precedence is expressed at high levels in this species, and providing interesting insights for an area-wide RPW management strategy such as the SIT

Entwicklung, Charakterisierung und Anwendung von In-liquid-Elektronenabbildungs- und Beugungstechniken für die hochauflösende Strukturanalyse

Spotting the mesoscale structural dynamics of biochemical processes in vivo with atomic-level detail has been a great technological challenge. Since a majority of these occur naturally in the solution phase, techniques allowing in-liquid observations are particularly attractive to the scientific community. Even though spectroscopic techniques permit straightforward solution-phase measurements, they nevertheless fail to provide direct structural information. Scattering techniques are mostly applied for such applications. In-liquid sample preparation techniques for electrons, which offer a greater scattering cross-section compared to X-rays, is quite challenging. The low penetration depth of the electrons imposes an additional constraint on the sample thickness. This thesis presents the author’s contribution towards the modification of the existing liquid cell technology for in-liquid real-space imaging and diffraction. Silicon based micro- and nanofabrication technology has been used to produce 20 nm thin silicon nitride windows for nanofluidic cells. The behaviour of nanofluidic cells under vacuum was characterized using a thin-film interferometer. These measurements provided insight into the deformation occurring in the silicon nitride windows, which resulted in an increase in specimen thickness. These issues led to the idea of the environmental liquid cell (ELC), where the environmental cell concept was combined with nanofluidic cell technology. The newly developed ELC method was shown to demonstrate controllable liquid thickness, which allowed imaging of gold nanoparticles, polystyrene beads, and ferritin molecules with sub-nm spatial resolution. The same technique was utilized to acquire diffraction from liquid water at room temperature. The scattering data provided information about the O•••H and O•••O pair distribution function, from which the coordination number was extracted and the values were 1.91 and 5,01, respectively. Further, the number of hydrogen bonds per water molecule was computed to be 3.8, implying a nearly tetrahedral structure of water. Despite delivering very promising results, the ELC technique still cannot be used for phase contrast imaging which require windows as thin as 10 nm. Moreover, the windows in the ELC are prone to failure. These shortcomings prompted the design idea of the elliptical multi-window liquid cell for phase-contrast imaging.Die Untersuchung von Strukturdynamik biochemischer Prozesse mit atomarer räumlicher Auflösung in vivo ist eine große technische Herausforderung. Da diese Prozesse meist in wässrigem Milieu auftreten sind Techniken, die Beobachtungen in flüssiger Form ermöglichen, für Wissenschaftler besonders attraktiv. Auch wenn spektroskopische Techniken einfache Messungen in der Lösungsphase erlauben, liefern sie dennoch keine direkten Strukturinformationen. Für solche Anwendungen werden meist Streuungstechniken eingesetzt. Präparationstechniken für flüssige Proben, welche mittels Elektronenmikroskopie oder Elektronenbeugung untersucht werden sollen, stellen im Vergleich zu den auf Röntgenstrahlen basierten Analogen eine große Herausforderung dar. Ein wesentlicher Grund hierfür ist der größere Streuquerschnitt der Elektronen, welcher zu einer geringeren Eindringtiefe führt und somit sehr dünne Proben erfordert. In dieser Arbeit wird der Beitrag des Autors zur Modifizierung der bestehenden Flüssigkeitszellentechnologie für die Realabbildung als auch Beugung von flüssigen Proben vorgestellt. Auf Silizium basierende Mikro- und Nanofabrikationstechnologien wurden eingesetzt, um 20 nm dünne Siliziumnitridfenster für Nanofluidikzellen herzustellen. Das Verhalten von Nanofluidikzellen unter Vakuum wurde mit Hilfe eines Dünnschichtinterferometers charakterisiert. Diese Messungen gaben Aufschluss über die in den Siliziumnitridfenstern auftretende Verformung, die zu einer unerwünschten Zunahme der Probendicke führte. Um dieses Problem zu umgehen, wurde die Idee der Umgebungsflüssigkeitszelle (ELC) konzipiert. Hierbei handelt es sich im Wesentlichen um eine Kombination von Ansätzen herkömmlicher environmental Transmissionselektronenmikroskopie mit der Nanofluidik-Zellentechnologie. Die neu entwickelte ELC-Methode erlaubte die Verwirklichung eines Flüssigkeitsfilms kontrollierbarer Dicke, was seinerseits die Abbildung von Goldnanopartikeln, Polystyrolkügelchen und Ferritinmolekülen mit einer räumlichen Auflösung von besser als einem Nanometer ermöglichte. Dieselbe Technik wurde zur Erfassung der Beugung an flüssigem Wasser bei Raumtemperatur verwendet. Die Streudaten lieferten Informationen über die O---H- und O---O-Paar-Verteilungsfunktion, aus denen die Koordinationszahl extrahiert wurde und die Werte 1,91 bzw. 5,01 betrugen. Weiterhin wurde berechnet, dass die Anzahl der Wasserstoffbrückenbindungen pro Wassermolekül 3,8 beträgt, was eine nahezu tetraedrische Struktur des Wassers impliziert. Obwohl die ELC-Technik sehr vielversprechende Ergebnisse liefert, konnte sie bisher noch nicht für die Phasenkontrast-Bildgebung eingesetzt werden. Hierfür sind Siliziumnitridfenster von etwa 10 nm Dicke erforderlich. Darüber hinaus sind die soweit genutzten Fenster in der ELC fragil, und somit unzuverlässig. Diese Unzulänglichkeiten gaben den Anstoß zu der Konstruktionsidee der elliptischen Mehrfenster-Flüssigkeitszelle für die Phasenkontrast-Bildgebung

Entwicklung, Charakterisierung und Anwendung von In-liquid-Elektronenabbildungs- und Beugungstechniken für die hochauflösende Strukturanalyse

Spotting the mesoscale structural dynamics of biochemical processes in vivo with atomic-level detail has been a great technological challenge. Since a majority of these occur naturally in the solution phase, techniques allowing in-liquid observations are particularly attractive to the scientific community. Even though spectroscopic techniques permit straightforward solution-phase measurements, they nevertheless fail to provide direct structural information. Scattering techniques are mostly applied for such applications. In-liquid sample preparation techniques for electrons, which offer a greater scattering cross-section compared to X-rays, is quite challenging. The low penetration depth of the electrons imposes an additional constraint on the sample thickness. This thesis presents the author’s contribution towards the modification of the existing liquid cell technology for in-liquid real-space imaging and diffraction. Silicon based micro- and nanofabrication technology has been used to produce 20 nm thin silicon nitride windows for nanofluidic cells. The behaviour of nanofluidic cells under vacuum was characterized using a thin-film interferometer. These measurements provided insight into the deformation occurring in the silicon nitride windows, which resulted in an increase in specimen thickness. These issues led to the idea of the environmental liquid cell (ELC), where the environmental cell concept was combined with nanofluidic cell technology. The newly developed ELC method was shown to demonstrate controllable liquid thickness, which allowed imaging of gold nanoparticles, polystyrene beads, and ferritin molecules with sub-nm spatial resolution. The same technique was utilized to acquire diffraction from liquid water at room temperature. The scattering data provided information about the O•••H and O•••O pair distribution function, from which the coordination number was extracted and the values were 1.91 and 5,01, respectively. Further, the number of hydrogen bonds per water molecule was computed to be 3.8, implying a nearly tetrahedral structure of water. Despite delivering very promising results, the ELC technique still cannot be used for phase contrast imaging which require windows as thin as 10 nm. Moreover, the windows in the ELC are prone to failure. These shortcomings prompted the design idea of the elliptical multi-window liquid cell for phase-contrast imaging.Die Untersuchung von Strukturdynamik biochemischer Prozesse mit atomarer räumlicher Auflösung in vivo ist eine große technische Herausforderung. Da diese Prozesse meist in wässrigem Milieu auftreten sind Techniken, die Beobachtungen in flüssiger Form ermöglichen, für Wissenschaftler besonders attraktiv. Auch wenn spektroskopische Techniken einfache Messungen in der Lösungsphase erlauben, liefern sie dennoch keine direkten Strukturinformationen. Für solche Anwendungen werden meist Streuungstechniken eingesetzt. Präparationstechniken für flüssige Proben, welche mittels Elektronenmikroskopie oder Elektronenbeugung untersucht werden sollen, stellen im Vergleich zu den auf Röntgenstrahlen basierten Analogen eine große Herausforderung dar. Ein wesentlicher Grund hierfür ist der größere Streuquerschnitt der Elektronen, welcher zu einer geringeren Eindringtiefe führt und somit sehr dünne Proben erfordert. In dieser Arbeit wird der Beitrag des Autors zur Modifizierung der bestehenden Flüssigkeitszellentechnologie für die Realabbildung als auch Beugung von flüssigen Proben vorgestellt. Auf Silizium basierende Mikro- und Nanofabrikationstechnologien wurden eingesetzt, um 20 nm dünne Siliziumnitridfenster für Nanofluidikzellen herzustellen. Das Verhalten von Nanofluidikzellen unter Vakuum wurde mit Hilfe eines Dünnschichtinterferometers charakterisiert. Diese Messungen gaben Aufschluss über die in den Siliziumnitridfenstern auftretende Verformung, die zu einer unerwünschten Zunahme der Probendicke führte. Um dieses Problem zu umgehen, wurde die Idee der Umgebungsflüssigkeitszelle (ELC) konzipiert. Hierbei handelt es sich im Wesentlichen um eine Kombination von Ansätzen herkömmlicher environmental Transmissionselektronenmikroskopie mit der Nanofluidik-Zellentechnologie. Die neu entwickelte ELC-Methode erlaubte die Verwirklichung eines Flüssigkeitsfilms kontrollierbarer Dicke, was seinerseits die Abbildung von Goldnanopartikeln, Polystyrolkügelchen und Ferritinmolekülen mit einer räumlichen Auflösung von besser als einem Nanometer ermöglichte. Dieselbe Technik wurde zur Erfassung der Beugung an flüssigem Wasser bei Raumtemperatur verwendet. Die Streudaten lieferten Informationen über die O---H- und O---O-Paar-Verteilungsfunktion, aus denen die Koordinationszahl extrahiert wurde und die Werte 1,91 bzw. 5,01 betrugen. Weiterhin wurde berechnet, dass die Anzahl der Wasserstoffbrückenbindungen pro Wassermolekül 3,8 beträgt, was eine nahezu tetraedrische Struktur des Wassers impliziert. Obwohl die ELC-Technik sehr vielversprechende Ergebnisse liefert, konnte sie bisher noch nicht für die Phasenkontrast-Bildgebung eingesetzt werden. Hierfür sind Siliziumnitridfenster von etwa 10 nm Dicke erforderlich. Darüber hinaus sind die soweit genutzten Fenster in der ELC fragil, und somit unzuverlässig. Diese Unzulänglichkeiten gaben den Anstoß zu der Konstruktionsidee der elliptischen Mehrfenster-Flüssigkeitszelle für die Phasenkontrast-Bildgebung

Dynamic Heterogeneity and DNA Methylation in Embryonic Stem Cells

Cell populations can be strikingly heterogeneous, composed of multiple cellular states, each exhibiting stochastic noise in its gene expression. A major challenge is to disentangle these two types of variability and to understand the dynamic processes and mechanisms that control them. Embryonic stem cells (ESCs) provide an ideal model system to address this issue because they exhibit heterogeneous and dynamic expression of functionally important regulatory factors. We analyzed gene expression in individual ESCs using single-molecule RNA-FISH and quantitative time-lapse movies. These data discriminated stochastic switching between two coherent (correlated) gene expression states and burst-like transcriptional noise. We further showed that the “2i” signaling pathway inhibitors modulate both types of variation. Finally, we found that DNA methylation plays a key role in maintaining these metastable states. Together, these results show how ESC gene expression states and dynamics arise from a combination of intrinsic noise, coherent cellular states, and epigenetic regulation

Outcomes following autologous hematopoietic stem cell transplant for patients with relapsed Wilms' tumor: a CIBMTR retrospective analysis.

Despite the marked improvement in the overall survival (OS) for patients diagnosed with Wilms' tumor (WT), the outcomes for those who experience relapse have remained disappointing. We describe the outcomes of 253 patients with relapsed WT who received high-dose chemotherapy (HDT) followed by autologous hematopoietic stem cell transplant (HCT) between 1990 and 2013, and were reported to the Center for International Blood and Marrow Transplantation Research. The 5-year estimates for event-free survival (EFS) and OS were 36% (95% confidence interval (CI); 29-43%) and 45% (95 CI; 38-51%), respectively. Relapse of primary disease was the cause of death in 81% of the population. EFS, OS, relapse and transplant-related mortality showed no significant differences when broken down by disease status at transplant, time from diagnosis to transplant, year of transplant or conditioning regimen. Our data suggest that HDT followed by autologous HCT for relapsed WT is well tolerated and outcomes are similar to those reported in the literature. As attempts to conduct a randomized trial comparing maintenance chemotherapy with consolidation versus HDT followed by stem cell transplant have failed, one should balance the potential benefits with the yet unknown long-term risks. As disease recurrence continues to be the most common cause of death, future research should focus on the development of consolidation therapies for those patients achieving complete response to therapy