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Bronze Age Female figurine
No full textOne of the photographs captured by famous photographer Ara Güler during his visits at Anatolian sites.Black & white photograph
Excavation site of Hattusa
No full textExcavation site of Hattuša, the capital city of Hittites (today in the Çorum Province, Turkey) from their beginning in the 17th century BC until the collapse of the empire in early 12th century BC. By the 12th century the city came to cover an area of 182 hectars, surrounded by a 3.3 km long defensive wall. The Aslanlı Kapı (Lion Gate) with two stone lions were believed to protect the city from evil spirits. The Lion Gate was one of the six defensive walls of the city. Besides natural outcrops that were turned out to the part of the walls, massive ramparts were made to create artificial fortresses.Black & white photograph
Standing Hittite female figurine from 2,600-1,900 BC Early Bronze Age, Hasaoğlan
No full textStanding Hittite female figurine from 2,600-1,900 BC Early Bronze Age, Hasaoğlan. Her body is made out of elektrum (an alloy of gold and silver) whereas the face mask, breast, anklets and bracelets are of pure gold. Housed in the Museum of Anatolian Civilizations, Ankara.Black & white photograph
View of Boğazköy from Büyükkaya, Hattusa
No full textView of Boğazköy from Büyükkaya. As Büyükkale, Büyükkaya forms one of the two bastions at the Northeast side of the old city at Hattusa, the capital city of the Hittite Empire, today in the Çorum Province, Turkey. It was built as fortress for defense of the city. The Budaközü gorge and the footpaths between these bastions form a weak spot in the defense and to protect the small valley of Budakŏzŭ near Ambarlıkaya from attacks coming from the hills next to Büyükkaya or from the gorge, the Hittites made fortifications and gates in the stream, to close this entrance of the Hattusa.Black & white photograph
Binding induced conformational changes of proteins correlate with their intrinsic fluctuations: a case study of antibodies
No full textBackground: How antibodies recognize and bind to antigens can not be totally explained by rigid shape and electrostatic complimentarity models. Alternatively, pre- existing equilibrium hypothesis states that the native state of an antibody is not defined by a single rigid conformation but instead with an ensemble of similar conformations that co-exist at equilibrium. Antigens bind to one of the preferred conformations making this conformation more abundant shifting the equilibrium. Results: Here, two antibodies, a germline antibody of 36 - 65 Fab and a monoclonal antibody, SPE7 are studied in detail to elucidate the mechanism of antibody-antigen recognition and to understand how a single antibody recognizes different antigens. An elastic network model, Anisotropic Network Model (ANM) is used in the calculations. Pre- existing equilibrium is not restricted to apply to antibodies. Intrinsic fluctuations of eight proteins, from different classes of proteins, such as enzymes, binding and transport proteins are investigated to test the suitability of the method. The intrinsic fluctuations are compared with the experimentally observed ligand induced conformational changes of these proteins. The results show that the intrinsic fluctuations obtained by theoretical methods correlate with structural changes observed when a ligand is bound to the protein. The decomposition of the total fluctuations serves to identify the different individual modes of motion, ranging from the most cooperative ones involving the overall structure, to the most localized ones. Conclusion: Results suggest that the pre- equilibrium concept holds for antibodies and the promiscuity of antibodies can also be explained this hypothesis: a limited number of conformational states driven by intrinsic motions of an antibody might be adequate to bind to different antigens
The scent of a handshake
No full textSniffing our hand after a handshake may allow us to detect chemical signals produced by others
Impact of spinal manipulation on cortical drive to upper and lower limb muscles
No full textThis study investigates whether spinal manipulation leads to changes in motor control by measuring the recruitment pattern of motor units in both an upper and lower limb muscle and to see whether such changes may at least in part occur at the cortical level by recording movement related cortical potential (MRCP) amplitudes. In experiment one, transcranial magnetic stimulation input-output (TMS I/O) curves for an upper limb muscle (abductor pollicus brevis; APB) were recorded, along with F waves before and after either spinal manipulation or a control intervention for the same subjects on two different days. During two separate days, lower limb TMS I/O curves and MRCPs were recorded from tibialis anterior muscle (TA) pre and post spinal manipulation. Dependent measures were compared with repeated measures analysis of variance, with p set at 0.05. Spinal manipulation resulted in a 54.5% +/- 93.1% increase in maximum motor evoked potential (MEPmax) for APB and a 44.6% +/- 69.6% increase in MEPmax for TA. For the MRCP data following spinal manipulation there were significant difference for amplitude of early bereitschafts-potential (EBP), late bereitschafts potential (LBP) and also for peak negativity (PN). The results of this study show that spinal manipulation leads to changes in cortical excitability, as measured by significantly larger MEPmax for TMS induced input-output curves for both an upper and lower limb muscle, and with larger amplitudes of MRCP component post manipulation. No changes in spinal measures (i.e., F wave amplitudes or persistence) were observed, and no changes were shown following the control condition. These results are consistent with previous findings that have suggested increases in strength following spinal manipulation were due to descending cortical drive and could not be explained by changes at the level of the spinal cord. Spinal manipulation may therefore be indicated for the patients who have lost tonus of their muscle and/or are recovering from muscle degrading dysfunctions such as stroke or orthopaedic operations and/or may also be of interest to sports performers. These findings should be followed up in the relevant populations
The noisy channel mode for unsupervised word sense disambiguation
No full textWe introduce a generative probabilistic model, the noisy channel model, for unsupervised word sense disambiguation. In our model, each context C is modeled as a distinct channel through which the speaker intends to transmit a particular meaning S using a possibly ambiguous word W. To reconstruct the intended meaning the hearer uses the distribution of possible meanings in the given context P(S|C) and possible words that can express each meaning P(W|S). We assume P(W|S) is independent of the context and estimate it using WordNet sense frequencies. The main problem of unsupervised WSD is estimating context-dependent P(S|C) without access to any sense-tagged text. We show one way to solve this problem using a statistical language model based on large amounts of untagged text. Our model uses coarse-grained semantic classes for S internally and we explore the effect of using different levels of granularity on WSD performance. The system outputs fine-grained senses for evaluation, and its performance on noun disambiguation is better than most previously reported unsupervised systems and close to the best supervised systems
State foreclosure laws and the incidence of Mortgage Default
No full textThis study presents a numerical and an experimental study on an active vibration control system. The system includes a fully-clamped plate and two surface bonded piezoelectric actuators and a collocated velocity sensor at one of the actuator locations. One of the piezoelectric actuators is used for disturbance actuation and the other one is used for control actuation. A model based optimal velocity feedback controller is used as control algorithm. The disturbance and actuator models are obtained through experimental characterization of the plate under the effect of the disturbance source. A representative SIMULINK model is built in parallel to the development of the experimental setup in order to investigate performance of the controller for various control parameters. After the model based optimal controller is designed, performance of the optimal velocity feedback controller is validated with the experimental study by comparing the vibration suppression values at multiple modes of the structure. Results show that the developed control methodology effectively suppresses the vibration amplitudes at multiple modes of the structure and also vibration attenuation levels can be predicted accurately with the simulations for various controller design parameters. It is also demonstrated that using an optimal controller enhances the performance of the system as opposed to just using velocity feedback algorithm for the active vibration control of the smart plate