gebhart/patrepeval huggingface dataset:
Sensory Input Directs Spatial and Temporal Plasticity in Primary Auditory Cortex (2001)

The cortical representation of the sensory environment is continuously modified by experience. Changes in spatial (receptive field) and temporal response properties of cortical neurons underlie many forms of natural learning. The scale and direction of these changes appear to be determined by specific features of the behavioral tasks that evoke cortical plasticity. The neural mechanisms responsible for this differential plasticity remain unclear partly because important sensory and cognitive parameters differ among these tasks. In this report, we demonstrate that differential sensory experience directs differential plasticity using a single paradigm that eliminates the task-specific variables that have confounded direct comparison of previous studies. Electrical activation of the basal forebrain (BF) was used to gate cortical plasticity mechanisms. The auditory stimulus paired with BF stimulation was systematically varied to determine how several basic features of the sensory input direct plasticity in primary auditory cortex (A1) of adult rats. The distributed cortical response was reconstructed from a dense sampling of A1 neurons after 4 wk of BF-sound pairing. We have previously used this method to show that when a tone is paired with BF activation, the region of the cortical map responding to that tone frequency is specifically expanded. In this report, we demonstrate that receptive-field size is determined by features of the stimulus paired with BF activation. Specifically, receptive fields were narrowed or broadened as a systematic function of both carrier-frequency variability and the temporal modulation rate of paired acoustic stimuli. For example, the mean bandwidth of A1 neurons was increased (+60%) after pairing BF stimulation with a rapid train of tones and decreased (-25%) after pairing unmodulated tones of different frequencies. These effects are consistent with previous reports of receptive-field plasticity evoked by natural learning. The maximum cortical following rate and minimum response latency were also modified as a function of stimulus modulation rate and carrier-frequency variability. The cortical response to a rapid train of tones was nearly doubled if BF stimulation was paired with rapid trains of random carrier frequency, while no following rate plasticity was observed if a single carrier frequency was used. Finally, we observed significant increases in response strength and total area of functionally defined A1 following BF activation paired with certain classes of stimuli and not others. These results indicate that the degree and direction of cortical plasticity of temporal and receptive-field selectivity are specified by the structure and schedule of inputs that co-occur with basal forebrain activation and suggest that the rules of cortical plasticity do not operate on each elemental stimulus feature independently of others.
A 4D Light-Field Dataset and CNN Architectures for Material Recognition (2016)

We introduce a new light-field dataset of materials, and take advantage of the recent success of deep learning to perform material recognition on the 4D light-field. Our dataset contains 12 material categories, each with 100 images taken with a Lytro Illum, from which we extract about 30,000 patches in total. To the best of our knowledge, this is the first mid-size dataset for light-field images. Our main goal is to investigate whether the additional information in a light-field (such as multiple sub-aperture views and view-dependent reflectance effects) can aid material recognition. Since recognition networks have not been trained on 4D images before, we propose and compare several novel CNN architectures to train on light-field images. In our experiments, the best performing CNN architecture achieves a 7% boost compared with 2D image classification (70% to 77%). These results constitute important baselines that can spur further research in the use of CNNs for light-field applications. Upon publication, our dataset also enables other novel applications of light-fields, including object detection, image segmentation and view interpolation.
Starting 2023 (2023)

Happy New Year! IEEE Wireless Communications continues to strive for excellence in the field of wireless communications. In 2022, it achieved the highest bibliometric level because of its inauguration with an impact factor of 12.777, Eigenfactor of 0.01708, article influence score of 3.063, and CiteScore of 22. Kudos to our readers, authors, reviewers, editors, and the publication staff! In 2022, we published a total of 114 articles, of which 51 were derived from nine special issues (SI) and feature topics, covering topics in network slicing, 6G, enhanced fronthaul, security, protocols and algorithms, blockchain, emergency communications, artificial intelligence, and coexistence of drone and terrestrial networks. Thanks to our column editors, we were able to enlighten readers via column articles in Spectrum Policy and Regulatory Issues, Industry Perspectives, Book Reviews, and Scanning the Literature.
Genetic Immunization with Plasmid DNA Mediated by Electrotransfer (2011)

The concept of DNA immunization was first advanced in the early 1990s, but was not developed because of an initial lack of efficiency. Recent technical advances in plasmid design and gene delivery techniques have allowed renewed interest in the idea. Particularly, a better understanding of genetic immunization has led to construction of optimized plasmids and the use of efficient molecular adjuvants. The field also took great advantage of new delivery techniques such as electrotransfer. This is a simple physical technique consisting of injecting plasmid DNA into a target tissue and applying an electric field, allowing up to a thousandfold more expression of the transgene than naked DNA. DNA immunization mediated by electrotransfer is now effective in a variety of preclinical models against infectious or acquired diseases such as cancer or autoimmune diseases, and is making its way through the clinics in several ongoing phase I human clinical trials. This review will briefly describe genetic immunization mediated by electrotransfer and the main fields of application.
Antimicrobial activity of the quinoline derivative HT61, effective against non-dividing cells, in Staphylococcus aureus biofilms (2020)

Abstract Staphylococcus aureus is an opportunistic pathogen responsible for a wide range of chronic infections. Disease chronicity is often associated with biofilm formation, a phenotype that confers enhanced tolerance towards antimicrobials, a trait which can be attributed to a dormant, non-dividing subpopulation within the biofilm. Development of antibiofilm agents that target these populations could therefore improve treatment success. HT61 is a quinoline derivative that has demonstrated efficacy towards non-dividing planktonic Staphylococcus spp . and therefore, in principal, could be effective against staphylococcal biofilms. In this study HT61 was tested on mature S. aureus biofilms, assessing both antimicrobial efficacy and characterising the cellular response to treatment. HT61 was found to be more effective than vancomycin in killing S. aureus biofilms (minimum bactericidal concentrations: HT61; 32 mg/L, vancomycin; 64 mg/L), and in reducing biofilm biomass. Scanning electron microscopy of HT61-treated biofilms also revealed disrupted cellular structure and biofilm architecture. HT61 treatment resulted in increased expression of proteins associated with the cell wall stress stimulon and dcw cluster, implying global changes in peptidoglycan and cell wall biosynthesis. Altered expression of metabolic and translational proteins following treatment also confirm a general adaptive response. These findings suggest that HT61 represents a new treatment for S. aureus biofilm-associated infections that are otherwise tolerant to conventional antibiotics targeting actively dividing cells.
Effect of Areca Nut on Helicobacter pylori-Induced Gastric Diseases in Mice (2016)

Areca nut (AN) chewing is a habit in many countries in Central, Southern, and Southeast Asia. It is strongly associated with the occurrence of oral, pharyngeal, and esophageal cancer as well as systemic inflammation. However, the association between AN intake and the development of gastric lesions has not yet been identified. The aim of this study was to investigate the effect of AN on gastric diseases using a mouse model for <i>Helicobacter pylori</i> infection. We studied four groups of mice: those fed a normal diet (ND), those fed a diet containing 2.5% AN (AD), those fed ND and infected with <i>H. pylori</i> PMSS1 strain (ND/HP), and those fed AD and infected with <i>H. pylori</i> PMSS1 strain (AD/HP). Food intake and body weight were monitored weekly during the experiments. At 10 weeks, the mice were sacrificed, and the stomach weight, <i>H. pylori</i> colonization, and gastric inflammation were evaluated. The stomach weight had increased significantly in the ND/HP and AD/HP groups along with increases in <i>H. pylori</i> colonization; however, there was no significant difference between these two groups with respect to stomach weight and colonization. On histological grading, mononuclear cell infiltration was severer in the AD/HP group than in the ND/HP group. These data suggest that chronic gastric inflammation was aggravated by AN treatment in the mice with <i>H. pylori</i>-induced gastric lesions. Furthermore, as previously suggested, this animal model is useful to determine the effect of potential carcinogens on gastric lesions induced by H. pylori infection.
Remarkable Effects of Metal, Solvent, and Oxidant on Metalloporphyrin-Catalyzed Enantioselective Epoxidation of Olefins (1997)

Three metal complexes of one particular homochiral porphyrin were investigated as catalysts for enantioselective epoxidation of unfunctionalized olefins under various reaction conditions. Much better results were obtained with the iron and ruthenium complexes than with the manganese derivative. The absence of any effect of amines on the iron porphyrin-catalyzed reaction in benzene, as well as the superior results in aromatic as opposed to both more and less polar nonaromatic solvents, suggest that specific association of aromatic molecules to the metalloporphyrin affects its solution structure. Strong evidence for the involvement of active oxidants that are more selective than trans-dioxoruthenium(VI) porphyrin is provided by the significant effect of primary oxidants on the ruthenium porphyrin-catalyzed reactions. Preliminary results with the iron complex of an only slightly modified porphyrin under the optimized reaction conditions found in this study resulted in epoxidation of styrene and 4-chlorostyrene to their epoxides with enantiomeric excesses identical to the best ever reported. These results were obtained with an unprecedented large number of catalytic turnovers, requiring only 0.01 mol % of catalyst.
Real-Time in Vivo Detection of H2O2 Using Hyperpolarized 13C-Thiourea (2017)

Reactive oxygen species (ROS) are essential cellular metabolites widely implicated in many diseases including cancer, inflammation, and cardiovascular and neurodegenerative disorders. Yet, ROS signaling remains poorly understood, and their measurements are a challenge due to high reactivity and instability. Here, we report the development of <sup>13</sup>C-thiourea as a probe to detect and measure H<sub>2</sub>O<sub>2</sub> dynamics with high sensitivity and spatiotemporal resolution using hyperpolarized <sup>13</sup>C magnetic resonance spectroscopic imaging. In particular, we show <sup>13</sup>C-thiourea to be highly polarizable and to possess a long spin-lattice relaxation time (T<sub>1</sub>), which enables real-time monitoring of ROS-mediated transformation. We also demonstrate that <sup>13</sup>C-thiourea reacts readily with H<sub>2</sub>O<sub>2</sub> to give chemically distinguishable products in vitro and validate their detection in vivo in a mouse liver. This study suggests that <sup>13</sup>C-thiourea is a promising agent for noninvasive detection of H<sub>2</sub>O<sub>2</sub> in vivo. More broadly, our findings outline a viable clinical application for H<sub>2</sub>O<sub>2</sub> detection in patients with a range of diseases.
Water-soluble tetrapodal N,O ligands incorporating soft N-heterocycles for the selective complexation of Am(iii) over Ln(iii) (2009)

A series of four water-soluble N,O-tetrapodal ligands derived from ethylenediamine, bearing hard acetate groups and soft N-heterocycles, either pyridine or pyrazine, was developed to study the impact of the softness of N-donors on the complexation properties with trivalent f ions. Two novel ligands of enhanced soft character, bearing three pyridines (L3py) or three pyrazines (L3pz), were synthesized and the related lanthanide complexes were studied in solution. The ligand containing three pyridylmethyl moieties L3py gives complexes with a coordination similar to EDTA, i.e. a hexadentate coordination mode as indicated by NMR and luminescence decays (q = 3) and stability constants in the range log β110 = 6.99–9.3 (La–Lu). On the other hand, the softest molecule L3pz forms much less stable complexes with log β110 = 4.0–4.4 (La–Eu). The selective back-extraction of Am(III) from organic solutions containing 4f and 5f elements was tested with the four water-soluble complexing agents. The ligand L3pz demonstrates poor stripping ability and selectivity. In contrast, the three ligands Lpy, Lpz and L3py give interesting back-extraction results with Eu/Am separation factors ranging from 36 to 46, which are significantly higher than with HEDTA. This exemplifies the role of the N-heterocycle softness in enhancing the separation between Am(III) and Eu(III). Interestingly, the pyrazine-based ligand, Lpz, demonstrates the best stripping properties, with a distribution factor that approaches that of HEDTA in the same conditions (DAm ≈ 0.3). This molecule is a good compromise between softness and hardness and forms complexes still stable at pH 3 due to its low basicity.
Novel Benzofurans with 99mTc Complexes as Probes for Imaging Cerebral β-Amyloid Plaques (2010)

Two novel benzofuran derivatives coupled with (99m)Tc complexes were tested as probes for imaging cerebral β-amyloid plaques using single photon emission tomography. Although both derivatives bound to Aβ(1-42) aggregates, (99m)Tc-BAT-BF showed higher affinity than (99m)Tc-MAMA-BF. In sections of brain tissue from an animal model of AD, (99m)Tc-BAT-BF clearly labeled β-amyloid plaques. In biodistribution experiments using normal mice, (99m)Tc-BAT-BF displayed high uptake soon after its injection and washed out from the brain rapidly, a highly desirable feature for an imaging agent. (99m)Tc-BAT-BF may be a potential probe for imaging β-amyloid plaques in Alzheimer's brains.
Link between Primate Lentiviral Coreceptor Usage and Nef Function (2013)

Simian immunodeficiency virus (SIVsmm) infection of sooty mangabeys (Cercocebus atys) is characterized by stable CD4(+) T cell counts despite high plasma levels of CCR5-tropic viruses. However, in rare instances, SIVsmm acquires CXCR4 coreceptor tropism and causes severe CD4(+) T cell depletion, albeit without clinical signs of immunodeficiency. Here, we show that CXCR4-tropic SIVsmm strains lost their ability to downmodulate TCR-CD3 by evolving unusual Nef mutations that initially reduced (I132V) and subsequently disrupted (I123L and L146F) interaction with the CD3 ζ chain. This coevolution of Env and Nef function suggests that CD3 downmodulation is advantageous for viral replication in activated CCR5(+) memory T cells, but not in resting naive CXCR4(+) T cells that have not yet undergone TCR-CD3-mediated stimulation. This may explain why HIV-1, which generally lacks the CD3 downmodulation function, commonly switches to CXCR4 usage, whereas this is extremely rare for SIV strains that have retained this Nef activity.
Aperture dependence of the mixing efficiency, the signal-to-noise ratio, and the speckle number in coherent lidar receivers (1998)

With the aid of the van Cittert-Zernike theorem we develop an analytical expression for the ensemble-averaged heterodyne mixing efficiency in coherent lidar receivers that are looking at a diffuse target that is in the receiver's far field. Our extremely simple and straightforward analysis shows that the dependence of the mixing efficiency on the receive aperture size dR first follows a parabolic decrease and later approaches a (dR)(-2) function. As a consequence, the signal-to-noise ratio does not increase proportionally to the aperture area but saturates. For the system model chosen, the heterodyne mixing efficiency exhibits the same functional dependence on the lidar geometry as the reciprocal of the number of speckle cells within the receive aperture.
Coupling of transcription and replication machineries in λ DNA replication initiation: evidence for direct interaction of Escherichia coli RNA polymerase and the λO protein (2010)

Transcription proceeding downstream of the λ phage replication origin was previously shown to support initial steps of the λ primosome assembly in vitro and to regulate frequency and directionality of λ DNA replication in vivo. In this report, the data are presented indicating that the RNA polymerase β subunit makes a direct contact with the λO protein, a replication initiator of λ phage. These results suggest that the role of RNA polymerase during the initiation of λ phage DNA replication may be more complex than solely influencing DNA topology. Results demonstrated in this study also show that gyrase supercoiling activity stimulates the formation of a complex between λO and RNA polymerase, suggesting that the introduction of negative supercoils by DNA gyrase, besides lowering the energy required for DNA strand separation, may play an additional role in modeling protein-protein interactions at early steps of DNA replication initiation.
Improving Loran Coverage with Low Power Transmitters (2009)

Enhanced Loran ( eLoran ) is currently being implemented to provide back up to global navigation satellite systems (GNSS) in many critical and essential applications. In order to accomplish this, eLoran needs to provide a high level of availability throughout its desired coverage area. While the current Loran system is generally capable of accomplishing this, worldwide, there remain a number of known areas where improved coverage is desirable or necessary. One example is in the middle of the continental United States where the transmitter density is not adequate for providing the desired availability for applications such as aviation in some parts. This paper examines the use of lower power, existing assets such as differential GPS (DGPS) and Ground Wave Emergency Network (GWEN) stations to enhance coverage and fill these gaps. Two areas covered by the paper are the feasibility and performance benefits of using the antennas at these sites. Using DGPS, GWEN or other existing low frequency (LF) broadcast towers requires the consideration of several factors. The first is the ability of the transmitting equipment to efficiently broadcast on these antennas, which are significantly shorter than those at a Loran station. Recent tests at the US Coast Guard Loran Support Unit (LSU) demonstrated the performance of a more efficient transmitter. This technology allows for the effective use of smaller antennas at lower power levels. Second is the ability to broadcast a navigation signal that is compatible with the Loran system and the potential DPGS broadcast (when using a DGPS antenna). The paper examines some possibilities for navigation signals. The goal is to develop a suitable low power signal that enhances navigation and is feasible for the transmission system. The second part of the paper examines the benefits of using these stations. The benefits depend on the location of the stations and the ability seamlessly to integrate them within the existing Loran infrastructure. Analysis of these factors is presented and the coverage benefits are examined.
Efficient Synthesis of Unsymmetrical Bolaamphiphiles for Spontaneous Formation of Vesicles and Disks with a Transmembrane Organization (2001)

Unsymmetrical bolaamphiphiles 1a−1d bearing a neutral glycosidic polar head and an electropositive ammonium group at opposite ends of a polymethylene bridging spacer were efficiently synthesized. An additional alkoxy group was introduced at the anomeric site of the carbohydrate in order to yield anomerically defined compounds, to allow the modulation of hydrophobic−hydrophilic balance (HLB), and to increase the dissymmetry of the monomers. The self-assembling properties of the bolaphiles 1a−1d were investigated in both concentrated and more diluted aqueous media and were characterized in a variety of ways. An appropriate modulation of the HLB allowed us to obtain spontaneous formation of stable vesicles characterized by a transmembrane conformation of the lipids. Freeze fracture electron microscopy clearly demonstrated an unusual transformation of the vesicular systems into disks upon heating.
K562 killing by K, IL 2-responsive NK, and T cells involves different effector cell post-binding trigger mechanisms. (1986)

The monoclonal antibody 13.3 specifically blocks the trigger process of the NK-K562 cytolytic sequence at a post-binding effector cell level. This antibody was used to define differences in the lytic trigger processes of NK and other mechanisms of K562 lysis. Monoclonal antibody 13.3 inhibited lysis of K562 target cells by freshly isolated peripheral blood lymphocytes (PBL) and purified large granular lymphocytes (LGL), but had no inhibitory effect on antibody-dependent cell-mediated cytotoxicity to K562 by these effectors. Lectin-dependent cellular cytotoxicity (LDCC) to this target cell was also unresponsive to 13.3. The 13.3-induced inhibition of NK-K562 lytic activity persisted when PBL were activated in culture with interleukin 2 (IL 2) for periods up to 48 hr. After 48 hr of culture, the degree of inhibition diminished progressively in medium containing fetal calf serum but not in medium containing autologous serum. This 13.3-unresponsive lytic activity in cultured PBL could be attributed to more than one cell type and was present in both the LGL and Fc gamma receptor-depleted T cell fraction. Thus, K562 lysis by freshly isolated human lymphocytes via NK, K, and LDCC mechanisms is characterized by heterogeneity of the post-binding effector cell trigger mechanism. K562 lysis by lymphocytes cultured with IL 2 is similarly heterogeneous.
Effect of contralateral acoustic stimulation on 2f1−f2 acoustic distortion in human ears (1989)

The normal human cochlea is known to exhibit acoustic nonlinearity, observed most easily as a 2f1−f2 distortion product tone in response to two tonal stimuli. This distortion product is physiologically vulnerable, and can be influenced in animals by electrical stimulation of the cochlear efferent nerves. The function of the efferent cochlear innervation is poorly understood but currently revived theory suggests a feedback system may exist between the opposite cochlea, influencing cochlear micromechanics through the outer hair cells [D. O. Kim, Hear. Res. 22, 105–114 (1986)]. The influence of a contralateral acoustic stimulus on cochlear nonlinearity was studied in human subjects through the changes observed in the 2f1−f2 distortion product. The influence of interaural acoustic transmission of the stimulus was controlled by using constant SPL stimuli on subjects with varying degrees of sensorineural hearing loss in the stimulated (contralateral) ear. Results indicate a slight suppression in distortion product with no significant frequency tuning. Strong correlation with middle ear reflex threholds and lack of correlation with sensation level indicate the suppression is not caused by a cochlea-to-cochlea neural mechanism, and is likely caused by the middle ear reflex.