gebhart/patrepeval huggingface dataset:
Optical Space-Time Division Multiple Access (2012)

This work presents an approach to multiple access for free-space laser communication (lasercom) called space-time division multiple access, which aggregates traffic from multiple users at the network edge. The objective is to share resources to lower the cost, size, weight, and power consumption per user, thereby making lasercom feasible for users that require only moderate average information rates. This concept relies on fast, agile electronic beam steering, which was implemented in this investigation using liquid crystal optical phased arrays. We designed and built an experimental terminal incorporating a bidirectional communication aperture that was shared among the users, and two independently operated acquisition and tracking apertures. Using two remote user terminals, experiments were conducted to measure access node performance for a variety of operating conditions traceable to anticipated applications. The transmit and receive directions of the downlink and uplink communications channels were rapidly hopped between the two users, and data were exchanged between the access node and a user while the optical channel dwelled on the latter. Results showed that the measured information throughput efficiency correlated well with model predictions and was high enough to realize the expected advantages in applications with many users. Throughput efficiencies, defined as the actual data throughput as a percentage of the throughput without multiple access, exceeded 85% for dwell times of 100 ms and greater. This translates into an average information rate of 400 Mb/s for as many as 20 simultaneous users. Current optical phased arrays are capable of providing fast transitions between remote users, with values measured in the range 10-18 ms. The use of persistent tracking links was a key factor in achieving fast transitions, and it was found that motion of the remote terminals had no significant impact on performance.
Ultraviolet‐B‐induced stress and changes in gene expression in Arabidopsis thaliana: role of signalling pathways controlled by jasmonic acid, ethylene and reactive oxygen species (1999)

ABSTRACT Treatment with supplementary UV‐B resulted in decreases in transcripts of the photosynthetic genes Lhcb and psbA and concomitant increase in transcripts of two pathogen‐related genes, PR‐1 and PDF1·2 , in Arabidopsis thaliana . UV‐B exposure caused increases in jasmonic acid (JA) levels and ethylene production. UV‐B treatment of jar1 and etr1‐1 mutants, which are insensitive to JA and ethylene, respectively, showed that the increase in PR‐1 transcripts was dependent on ethylene and PDF1·2 transcripts on both JA and ethylene. In contrast, the down‐regulation of photosynthetic transcripts was independent of both compounds. Previous studies have indicated a role for reactive oxygen species (ROS) in the UV‐B‐induced down‐regulation of the photosynthetic genes and up‐regulation of PR‐1 genes. Here we have shown that ROS are also required for the UV‐B‐induced up‐regulation of PDF1·2 genes. The results indicate that the effects of UV‐B on the three sets of genes are mediated through three distinct signal transduction pathways which are similar, but not identical, to pathways initiated in response to pathogen infection. In addition, the increased sensitivity of both jar1 and etr1‐1 mutants to UV‐B radiation, as compared with wild‐type plants, indicated that intact JA and ethylene signal pathways are required for defence against UV‐B damage.
Electrospun Nanostructured Scaffolds for Tissue Engineering Applications (2007)

Despite being known for decades (since 1934), electrospinning has emerged recently as a very widespread technology to produce synthetic nanofibrous structures. These structures have morphologies and fiber diameters in a range comparable with those found in the extracellular matrix of human tissues. Therefore, nanofibrous scaffolds are intended to provide improved environments for cell attachment, migration, proliferation and differentiation when compared with traditional scaffolds. In addition, the process versatility and the highly specific surface area of nanofiber meshes may facilitate their use as local drug-release systems. Common electrospun nanofiber meshes are characterized by a random orientation. However, in some special cases, aligned distributions of the fibers can be obtained, with an interconnected microporous structure. The characteristic pore sizes and the inherent planar structure of the meshes can be detrimental for the desired cell infiltration into the inner regions, and eventually compromise tissue regeneration. Several strategies can be followed to overcome these limitations, and are discussed in detail here.
Isolation and Mapping of a Family of Putative Zinc-finger Protein cDNAs from Rice (1998)

To understand the functions of rice homologues of the Arabidopsis flowering-time gene CONSTANS (CO) and salt-tolerance gene STO, we performed a similarity search of the single-run sequence data of cDNA clones accumulated by the Rice Genome Research Program, and isolated seven rice cDNA clones (S3574, C60910, S12569, R2931, R1479, R1577, and E10707) coding for proteins containing one of two zinc-finger-like motifs. Comparison of the deduced amino acid sequences between these cDNAs and the CO gene revealed significant similarities (46%-61%) in the region of zinc-finger motifs. A domain having a high content of basic amino acids at the C-terminus of the CO protein was found in the corresponding region of proteins predicted by from cDNAs S3574, C60910, and S12569. Two amino acid sequences, "CCADEAAL" and "FCV(L)EDRA," which were present inside each zinc-finger in the Arabidposis regulatory protein STO, were also found in each of the two zinc-finger regions of proteins predicted from cDNAs R2931, R1479, R1577, and E10707. Using restriction fragment length polymorphism (RFLP) linkage analysis, we determined the chromosomal location of the seven cDNA clones. The position of R2931 on the RFLP linkage map was closely linked to Hd-3, one of the putative quantitative trait loci (QTL) controlling heading date in rice.
An Unusual Microwave Mixer (1986)

Some preliminary measurements on an unusual microwave mixer configuration are reported. The mixer employied a single gate, packaged GaAs FET in a novel coaxial mount. The L.O. power and the I.F. were fed to and taken from the drain while the input R.F. signal was connected to the gate. A conversion gain of 2 dB and 270K DSB "mixer" noise temperature were measured at X band. Cooling the unit to 60K, a "mixer" noise temperature of 80K was obtained across a 10% bandwidth. At K band a 3 dB conversion loss and 880K DSB noise temperature were measured. The latter figure dropped to l80K at cryogenic temperatures.
An adaptive pam-4 5-Gb/s backplane transceiver in 0.25-μm CMOS (2003)

This paper describes a backplane transceiver, which uses pulse amplitude modulated four-level (PAM-4) signaling and continuously adaptive transmit-based equalization to move 2.5-GBd/s symbols totalling 5 Gb/s across typical FR-4 backplanes for total distances of up to 50 inches through two sets of backplane connectors. The 17-mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> device is implemented in a 0.25-μm CMOS process, operates off of 2.5- and 3.3-V supply voltages, and consumes 1 W.
Functional Characterization and Developmental Regulation of Mouse Telomerase RNA (1995)

Telomerase synthesizes telomeric DNA repeats onto chromosome ends de novo. The mouse telomerase RNA component was cloned and contained only 65 percent sequence identity with the human telomerase RNA. Alteration of the template region in vivo generated altered telomerase products. The shorter template regions of the mouse and other rodent telomerase RNAs could account for the shorter distribution of products (processivity) generated by the mouse enzyme relative to the human telomerase. Amounts of telomerase RNA increased in immortal cells derived from primary mouse fibroblasts. RNA was detected in all newborn mouse tissues tested but was decreased during postnatal development.
Raptor codes (2006)

LT-codes are a new class of codes introduced by Luby for the purpose of scalable and fault-tolerant distribution of data over computer networks. In this paper, we introduce Raptor codes, an extension of LT-codes with linear time encoding and decoding. We will exhibit a class of universal Raptor codes: for a given integer k and any real epsiv>0, Raptor codes in this class produce a potentially infinite stream of symbols such that any subset of symbols of size k(1+epsiv) is sufficient to recover the original k symbols with high probability. Each output symbol is generated using O(log(1/epsiv)) operations, and the original symbols are recovered from the collected ones with O(klog(1/epsiv)) operations. We will also introduce novel techniques for the analysis of the error probability of the decoder for finite length Raptor codes. Moreover, we will introduce and analyze systematic versions of Raptor codes, i.e., versions in which the first output elements of the coding system coincide with the original k elements
Semaphorin 4D, a lymphocyte semaphorin, enhances tumor cell motility through binding its receptor, plexinB1, in pancreatic cancer (2011)

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor, for which the development of new biomarkers and therapeutic targets has become critical. The main cause of poor prognosis in PDAC patients is the high invasive and metastatic potential of the cancer. In the present study, we report a new signaling pathway that was found to mediate the enhanced tumor cell motility in pancreatic cancer. Semaphorin 4D (Sema4D) is a ligand known to be expressed on different cell types, and has been reported to be involved in the regulation of immune functions, epithelial morphogenesis, and tumor growth and metastasis. In this study, we revealed for the first time that the cancer tissue cells expressing Sema4D in PDAC are tumor-infiltrating lymphocytes. The overexpression of Sema4D and of its receptor, plexinB1, was found to be significantly correlated with clinical factors, such as lymph node metastasis, distant metastasis, and poor prognosis in patients with PDAC. Through in vitro analysis, we demonstrated that Sema4D can potentiate the invasiveness of pancreatic cancer cells and we identified the downstream molecules. The binding of Sema4D to plexinB1 induced small GTPase Ras homolog gene family, member A activation and resulted in the phosphorylation of MAPK and Akt. In addition, in terms of potential therapeutic application, we clearly demonstrated that the enhanced-cell invasiveness induced by Sema4D could be inhibited by knockdown of plexinB1, suggesting that blockade of plexinB1 might diminish the invasive potential of pancreatic cancer cells. Our findings provide new insight into possible prognostic biomarkers and therapeutic targets in PDAC patients.
A recombinant single‐chain human class II MHC molecule (HLA‐DR1) as a covalently linked heterotrimer of α chain, β chain, and antigenic peptide, with immunogenicity in vitro and reduced affinity for bacterial superantigens (1997)

Major histocompatibility complex (MHC) class II molecules bind to numerous peptides and display these on the cell surface for T cell recognition. In a given immune response, receptors on T cells recognize antigenic peptides that are a minor population of MHC class II-bound peptides. To control which peptides are presented to T cells, it may be desirable to use recombinant MHC molecules with covalently bound antigenic peptides. To study T cell responses to such homogeneous peptide-MHC complexes, we engineered an HLA-DR1 cDNA coding for influenza hemagglutinin, influenza matrix, or HIV p24 gag peptides covalently attached via a peptide spacer to the N terminus of the DR1 beta chain. Co-transfection with DR alpha cDNA into mouse L cells resulted in surface expression of HLA-DR1 molecules that reacted with monoclonal antibodies (mAb) specific for correctly folded HLA-DR epitopes. This suggested that the spacer and peptide did not alter expression or folding of the molecule. We then engineered an additional peptide spacer between the C terminus of a truncated beta chain (without transmembrane or cytoplasmic domains) and the N terminus of full-length DR alpha chain. Transfection of this cDNA into mouse L cells resulted in surface expression of the entire covalently linked heterotrimer of peptide, beta chain, and alpha chain with the expected molecular mass of approximately 66 kDa. These single-chain HLA-DR1 molecules reacted with mAb specific for correctly folded HLA-DR epitopes, and identified one mAb with [MHC + peptide] specificity. Affinity-purified soluble secreted single-chain molecules with truncated alpha chain moved in electrophoresis as compact class II MHC dimers. Cell surface two-chain or single-chain HLA-DR1 molecules with a covalent HA peptide stimulated HLA-DR1-restricted HA-specific T cells. They were immunogenic in vitro for peripheral blood mononuclear cells. The two-chain and single-chain HLA-DR1 molecules with covalent HA peptide had reduced binding for the bacterial superantigens staphylococcal enterotoxin A and B and almost no binding for toxic shock syndrome toxin-1. The unique properties of these engineered HLA-DR1 molecules may facilitate our understanding of the complex nature of antigen recognition and aid in the development of novel vaccines with reduced superantigen binding.
Induction of Colonic Regulatory T Cells by Indigenous Clostridium Species (2010)

CD4(+) T regulatory cells (T(regs)), which express the Foxp3 transcription factor, play a critical role in the maintenance of immune homeostasis. Here, we show that in mice, T(regs) were most abundant in the colonic mucosa. The spore-forming component of indigenous intestinal microbiota, particularly clusters IV and XIVa of the genus Clostridium, promoted T(reg) cell accumulation. Colonization of mice by a defined mix of Clostridium strains provided an environment rich in transforming growth factor-β and affected Foxp3(+) T(reg) number and function in the colon. Oral inoculation of Clostridium during the early life of conventionally reared mice resulted in resistance to colitis and systemic immunoglobulin E responses in adult mice, suggesting a new therapeutic approach to autoimmunity and allergy.
Regional Angiogenesis Induced in Nonischemic Tissue by an Adenoviral Vector Expressing Vascular Endothelial Growth Factor (1997)

The feasibility of a single administration of a replication-deficient adenovirus (Ad) vector encoding the cDNA for human vascular endothelial growth factor (VEGF) (AdCMV.VEGF) to induce neovascularization in vivo in normal tissue was evaluated in retroperitoneal adipose tissue. Following administration of AdCMV.VEGF (10(9) pfu/50 microliters), maximal VEGF cDNA expression was observed at 2-5 days in the injected adipose tissue. No VEGF protein was detected at > or = 10 days in injected adipose tissue, and there was no increase in serum VEGF levels at any time. In vivo quantification of the number of blood vessels using 30x visualization of the adipose tissue demonstrated an increase in vessel number by 10 days, plateauing by 30 days with a 123% increase in vessel number compared to the control vector AdCMV.Null, despite the fact that no VEGF protein was detected after 5 days. Consistent with the in vivo data, histologic quantification of capillary number demonstrated an increase by day 5, reaching a 38% increase over AdCMV.Null by day 30. These observations demonstrate that an Ad vector carrying the VEGF cDNA is capable of inducing the growth of new blood vessels in a regional fashion in a relatively avascular, normal organ. This suggests in vivo Ad-mediated gene transfer may be useful for therapeutic angiogenesis in the treatment of ischemic cardiovascular disease.
Platelet-derived Growth Factor Expression and Function in Idiopathic Pulmonary Arterial Hypertension (2008)

PDGF may play an important role in human PAH. Novel therapeutic strategies targeting the PDGF pathway should be tested in clinical trials.
Optimization of linear placements for wirelength minimization with free sites (1999)

We study a type of linear placement problem arising in detailed placement optimization of a given cell row in the presence of white-space (extra sites). In this single-row placement problem, the cell order is fixed within the row; all cells in other rows are also fixed. We give the first solutions to the single-row problem: (i) a dynamic programming technique with time complexity O(m/sup 2/) where m is the number of nets incident to cells in the given row, and (ii) an O(m log m) technique that exploits the convexity of the wirelength objective. We also propose an iterative heuristic for improving cell ordering within a row; this can be run optionally before applying either (i) or (ii). Experimental results show an average of 6.5% wirelength improvement on industry test cases when our methods are applied to the final output of a leading industry placement tool.
Endothelial-leukocyte adhesion molecule 1 stimulates the adhesive activity of leukocyte integrin CR3 (CD11b/CD18, Mac-1, alpha m beta 2) on human neutrophils. (1991)

Two classes of adhesion molecules have well-defined roles in the attachment of unstimulated polymorphonuclear leukocytes (PMN) to cytokine-treated endothelial cells. Endothelial-leukocyte adhesion molecule 1 (ELAM-1) on endothelial cells interacts with specific carbohydrate residues on the PMN, and the leukocyte integrins (CD18 antigens) on PMN interact with intracellular adhesion molecule 1 and other structures on endothelium. Here we show that these two classes of molecules can act sequentially in an "adhesion cascade". Interaction of PMN with ELAM-1-bearing endothelial cells causes PMN to express enhanced adhesive activity of the integrin CR3 (CD11b/CD18). Expression of ELAM-1 on the cytokine-treated endothelium appears both necessary and sufficient for the stimulation of CR3 activity since blockade of ELAM-1 with mAbs prevents the activation of CR3 by cytokine-treated endothelium, and immobilized recombinant ELAM-1 activates CR3. The ability to activate CR3 is shared by chemattractants, suggesting that ELAM-1 may serve as a "tethered chemattractant." This hypothesis is strengthened by the observation that recombinant soluble ELAM-1 directs movement of PMN in chemotaxis chambers. These results suggest a mechanism by which multiple adhesive molecules may function together in diapedesis. ELAM-1 serves both as an adhesin and as a trigger that recruits the participation of additional adhesion molecules. Our results also suggest that ligands for adhesion molecules may also be "receptors" capable of generating intracellular signals.
Synthesis of medium-chain-length polyhydroxyalkanoates inArabidopsis thalianausing intermediates of peroxisomal fatty acid β-oxidation (1998)

Polyhydroxyalkanoate (PHA) is a family of polymers composed primarily of R-3-hydroxyalkanoic acids. These polymers have properties of biodegradable thermoplastics and elastomers. Medium-chain-length PHAs (MCL-PHAs) are synthesized in bacteria by using intermediates of the beta-oxidation of alkanoic acids. To assess the feasibility of producing MCL-PHAs in plants, Arabidopsis thaliana was transformed with the PhaC1 synthase from Pseudomonas aeruginosa modified for peroxisome targeting by addition of the carboxyl 34 amino acids from the Brassica napus isocitrate lyase. Immunocytochemistry demonstrated that the modified PHA synthase was appropriately targeted to leaf-type peroxisomes in light-grown plants and glyoxysomes in dark-grown plants. Plants expressing the PHA synthase accumulated electron-lucent inclusions in the glyoxysomes and leaf-type peroxisomes, as well as in the vacuole. These inclusions were similar to bacterial PHA inclusions. Analysis of plant extracts by GC and mass spectrometry demonstrated the presence of MCL-PHA in transgenic plants to approximately 4 mg per g of dry weight. The plant PHA contained saturated and unsaturated 3-hydroxyalkanoic acids ranging from six to 16 carbons with 41% of the monomers being 3-hydroxyoctanoic acid and 3-hydroxyoctenoic acid. These results indicate that the beta-oxidation of plant fatty acids can generate a broad range of R-3-hydroxyacyl-CoA intermediates that can be used to synthesize MCL-PHAs.
Caps Off to Juries: Noneconomic Damage Caps in Medical Malpractice Cases Ruled Unconstitutional (2011)

In 2005 the Georgia General Assembly (General Assembly) passed a controversial tort reform bill in an effort to reduce the cost of medical liability insurance for health care providers. In this bill, the legislature put a cap of $350,000 on noneconomic damages (pain and suffering) for medical malpractice cases. On March 22, 2010, the Georgia Supreme Court in Atlanta Oculoplastic Surgery, RC. v. Nestlehutt held these caps unconstitutional on grounds that they violate the state constitutional right to jury trial. By ruling on these grounds, the court was able to avoid weighing in on the competing interests of the medical industry and medical malpractice plaintiffs, which would have required an equal protection or due process analysis. The court, therefore, circumvented the politics of tort reform by way of a right to jury trial analysis.
Telomerase activity is repressed during differentiation of maturation-sensitive but not resistant human tumor cell lines. (1996)

The effects of induced differentiation on telomerase activity were examined in human acute promyelocytic leukemic (NB4) and human embryonal carcinoma (NTERA-2) cells exposed to all-trans-retinoic acid or hexamethylene bisacetamide. Retinoic acid treatment of NB4 and NTERA-2 cells, and hexamethylene bisacetamide treatment of NTERA-2 cells caused a decline in telomerase activity in differentiation-sensitive but not in resistant clones of these cell lines. Changes in telomerase activity as measured by the PCR-based telomeric repeat amplification protocol assay were noted by 24-72 h of exposure to the inducer, suggesting that its regulation may precede terminal differentiation. The degree of telomerase activity decline was greater in NB4 cells than in NTERA-2 cells, probably reflecting in part a more mature state of NB4 cells after 5 days of exposure to the inducer. Mixing of protein extracts from treated and untreated cells did not suggest the presence of diffusible telomerase inhibitors. Expression of the RNA component of telomerase was also examined in NB4 cells, and its decline correlated with the reduced telomerase activity measured by the telomeric repeat amplification protocol assay during induced differentiation of these tumor cells. Taken together, these findings indicate that telomerase is a regulated enzyme system during induced human tumor cell differentiation, showing an inverse relationship between the degree of differentiation and telomerase activity. These models will be be useful to study the regulation and role of telomerase during induced differentiation of human tumor cells.
Effect of high-density lipoproteins on the expression of adhesion molecules in endothelial cells (2002)

There are several potential mechanisms by which HDLs protect against atherosclerosis. One relates to the ability of HDLs to promote the efflux of cholesterol from macrophages. Another is the ability of HDLs to inhibit one of the earliest events in the development of atherosclerosis, namely the expression of vascular cell adhesion molecules in activated endothelial cells. This property has been reported in vitro in studies with both native and reconstituted HDLs. The inhibitory activity of reconstituted HDLs is influenced by the phospholipid composition of the particles. An inhibition of endothelial cell adhesion molecule expression has also been observed in some (but not all) studies conducted in vivo in mice and pigs. The mechanism of this potentially anti-atherogenic effect of HDLs remains uncertain, as does its contribution to the cardioprotective effects of HDLs in vivo.