Function generator eliminates necessity of series summation

Diode generator using four building-block circuits produces complex waveforms without the necessity of series summation. This highly specialized method of producing complex waveforms requires less power than present methods and uses simpler circuitry

Tower Foundations Bearing Above Weak Soils

A 13-level reinforced concrete structure was constructed on Marco Island in southwest Florida. The tower is located 200 feet from the Gulf of Mexico and has plan area dimensions of 115 by 170 feet. The field testing revealed the site was mantled with a 17-foot thick layer of firm sand. The sand stratum was underlain by a compressible 9-foot thick layer of silty sand which had an average SPT N-value of less than 2. Various methods of engineering analyses estimated total tower settlements to range from 1 to 8 inches. Actual measured settlement following the application of dead load was about 1 3/4 inches. An engineering inspection following construction revealed diagonal shear wall cracks

Benfordov zakon

Članak prikazuje zanimljivi statistički tekst s mogućom primjenom u otkrivanju prevara u financijskim izvještajima. Problem intrigira matematičare i financijske stručnjaka od 1881 godine kada je Simon Newcomb primijetio neočekivane pravilnosti ponavljanja znamenaka u logaritamskim tablicam

Disruption of Hydrogen Bonds between Major Histocompatibility Complex Class II and the Peptide N-Terminus Is Not Sufficient to Form a Human Leukocyte Antigen-DM Receptive State of Major Histocompatibility Complex Class II

Peptide presentation by MHC class II is of critical importance to the function of CD4+ T cells. HLA-DM resides in the endosomal pathway and edits the peptide repertoire of newly synthesized MHC class II molecules before they are exported to the cell surface. HLA-DM ensures MHC class II molecules bind high affinity peptides by targeting unstable MHC class II:peptide complexes for peptide exchange. Research over the past decade has implicated the peptide N-terminus in modulating the ability of HLA-DM to target a given MHC class II:peptide combination. In particular, attention has been focused on both the hydrogen bonds between MHC class II and peptide, and the occupancy of the P1 anchor pocket. We sought to solve the crystal structure of a HLA-DR1 molecule containing a truncated hemagglutinin peptide missing three N-terminal residues compared to the full-length sequence (residues 306–318) to determine the nature of the MHC class II:peptide species that binds HLA-DM. Here we present structural evidence that HLA-DR1 that is loaded with a peptide truncated to the P1 anchor residue such that it cannot make select hydrogen bonds with the peptide N-terminus, adopts the same conformation as molecules loaded with full-length peptide. HLA-DR1:peptide combinations that were unable to engage up to four key hydrogen bonds were also unable to bind HLA-DM, while those truncated to the P2 residue bound well. These results indicate that the conformational changes in MHC class II molecules that are recognized by HLA-DM occur after disengagement of the P1 anchor residue

Chimpanzees behave prosocially in a group-specific manner

Chimpanzees act cooperatively in the wild, but whether they afford benefits to others, and whether their tendency to act prosocially varies across communities, is unclear. Here, we show that chimpanzees from neighboring communities provide valuable resources to group members at personal cost, and that the magnitude of their prosocial behavior is group specific. Provided with a resource-donation experiment allowing free (partner) choice, we observed an increase in prosocial acts across the study period in most of the chimpanzees. When group members could profit (test condition), chimpanzees provided resources more frequently and for longer durations than when their acts produced inaccessible resources (control condition). Strikingly, chimpanzees’ prosocial behavior was group specific, with more socially tolerant groups acting more prosocially. We conclude that chimpanzees may purposely behave prosocially toward group members, and that the notion of group-specific sociality in nonhuman animals should crucially inform discussions on the evolution of prosocial behavior

Convergence and divergence in gesture repertoires as an adaptive mechanism for social bonding in primates

A key challenge for primates living in large, stable social groups is managing social relationships. Chimpanzee gestures may act as a time-efficient social bonding mechanism, and the presence (homogeneity) and absence (heterogeneity) of overlap in repertoires in particular may play an important role in social bonding. However, how homogeneity and heterogeneity in the gestural repertoire of primates relate to social interaction is poorly understood. We used social network analysis and generalized linear mixed modelling to examine this question in wild chimpanzees. The repertoire size of both homogeneous and heterogeneous visual, tactile and auditory gestures was associated with the duration of time spent in social bonding behaviour, centrality in the social bonding network and demography. The audience size of partners who displayed similar or different characteristics to the signaller (e.g. same or opposite age or sex category) also influenced the use of homogeneous and heterogeneous gestures. Homogeneous and heterogeneous gestures were differentially associated with the presence of emotional reactions in response to the gesture and the presence of a change in the recipient’s behaviour. Homogeneity and heterogeneity of gestural communication play a key role in maintaining a differentiated set of strong and weak social relationships in complex, multilevel societies

Fatigue behavior of materials for the sst - electron fractographic studies final report

Electron microscopic fractography to determine fatigue behavior of materials for supersonic transport - titanium, aluminum, molybdenum, and vanadiu

Multiple transcriptome mining coupled with tissue specific molecular cloning and mass spectrometry provide insights into agatoxin-like peptide conservation in decapod crustaceans

Over the past decade, in silico genome and transcriptome mining has led to the identification of many new crustacean peptide families, including the agatoxin-like peptides (ALPs), a group named for their structural similarity to agatoxin, a spider venom component. Here, analysis of publicly accessible transcriptomes was used to expand our understanding of crustacean ALPs. Specifically, transcriptome mining was used to investigate the phylogenetic/structural conservation, tissue localization, and putative functions of ALPs in decapod species. Transcripts encoding putative ALP precursors were identified from one or more members of the Penaeoidea (penaeid shrimp), Sergestoidea (sergestid shrimps), Caridea (caridean shrimp), Astacidea (clawed lobsters and freshwater crayfish), Achelata (spiny/slipper lobsters), and Brachyura (true crabs), suggesting a broad, and perhaps ubiquitous, conservation of ALPs in decapods. Comparison of the predicted mature structures of decapod ALPs revealed high levels of amino acid conservation, including eight identically conserved cysteine residues that presumably allow for the formation of four identically positioned disulfide bridges. All decapod ALPs are predicted to have amidated carboxyl-terminals. Two isoforms of ALP appear to be present in most decapod species, one 44 amino acids long and the other 42 amino acids in length, both likely generated by alternative splicing of a single gene. In carideans, a gene or terminal exon duplication appears to have occurred, with alternative splicing producing four ALPs, two 44 and two 42 amino acid isoforms. The identification of ALP precursor-encoding transcripts in nervous system-specific transcriptomes (e.g., Homarus americanus brain, eyestalk ganglia, and cardiac ganglion assemblies, finding confirmed using RT-PCR) suggests that members of this peptide family may serve as locally-released and/or hormonally-delivered neuromodulators in decapods. Their detection in testis- and hepatopancreas-specific transcriptomes suggests that members of the ALP family may also play roles in male reproduction and innate immunity/detoxification