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Sample records for auditory-nerve responses predict

  1. Modeling auditory-nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

    2014-01-01

    Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electrical transduction in the inner ear. Trains of biphasic, charge balanced pulses (anodic and cathodic) are used as stimuli to avoid damage of the tissue. The pulses of either polarity are capable of produ......Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electrical transduction in the inner ear. Trains of biphasic, charge balanced pulses (anodic and cathodic) are used as stimuli to avoid damage of the tissue. The pulses of either polarity are capable......μs, which is large enough to affect the temporal coding of sounds and hence, potentially, the communication abilities of the CI listener. In the present study, two recently proposed models of electric stimulation of the AN [1,2] were considered in terms of their efficacy to predict the spike timing...... for anodic and cathodic stimulation of the AN of cat [3]. The models’ responses to the electrical pulses of various shapes [4,5,6] were also analyzed. It was found that, while the models can account for the firing rates in response to various biphasic pulse shapes, they fail to correctly describe the timing...

  2. Wiener-kernel analysis of responses to noise of chinchilla auditory-nerve fibers

    NARCIS (Netherlands)

    Recio-Spinoso, A; Temchin, AN; van Dijk, P; Fan, YH; Ruggero, MA

    2005-01-01

    Responses to broadband Gaussian white noise were recorded in auditory-nerve fibers of deeply anesthetized chinchillas and analyzed by computation of zeroth-, first-, and second-order Wiener kernels. The first- order kernels ( similar to reverse correlations or "revcors") of fibers with characteristi

  3. A model of auditory nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

    peripheral for the cathodic phase. This results in an average difference of 200 μs in spike latency for AP generated by anodic vs cathodic pulses. It is hypothesized here that this difference is large enough to corrupt the temporal coding in the AN. To quantify effects of pulse polarity on auditory......, fail to correctly predict responses to anodic stimulation. This study presents a model that simulates AN responses to anodic and cathodic stimulation. The main goal was to account for the data obtained with monophasic electrical stimulation in cat AN. The model is based on an exponential integrate......-and-fire neuron with two partitions responding individually to anodic and cathodic stimulation. Membrane noise was parameterized based on reported relative spread of AN neurons. Firing efficiency curves and spike-latency distributions were simulated for monophasic and symmetric biphasic stimulation...

  4. Effects of Electrode Position on Spatiotemporal Auditory Nerve Fiber Responses: A 3D Computational Model Study

    Directory of Open Access Journals (Sweden)

    Soojin Kang

    2015-01-01

    Full Text Available A cochlear implant (CI is an auditory prosthesis that enables hearing by providing electrical stimuli through an electrode array. It has been previously established that the electrode position can influence CI performance. Thus, electrode position should be considered in order to achieve better CI results. This paper describes how the electrode position influences the auditory nerve fiber (ANF response to either a single pulse or low- (250 pulses/s and high-rate (5,000 pulses/s pulse-trains using a computational model. The field potential in the cochlea was calculated using a three-dimensional finite-element model, and the ANF response was simulated using a biophysical ANF model. The effects were evaluated in terms of the dynamic range, stochasticity, and spike excitation pattern. The relative spread, threshold, jitter, and initiated node were analyzed for single-pulse response; and the dynamic range, threshold, initiated node, and interspike interval were analyzed for pulse-train stimuli responses. Electrode position was found to significantly affect the spatiotemporal pattern of the ANF response, and this effect was significantly dependent on the stimulus rate. We believe that these modeling results can provide guidance regarding perimodiolar and lateral insertion of CIs in clinical settings and help understand CI performance.

  5. Modeling the Anti-masking Effects of the Olivocochlear Reflex in Auditory Nerve Responses to Tones in Sustained Noise

    OpenAIRE

    Chintanpalli, Ananthakrishna; Jennings, Skyler G.; Heinz, Michael G.; Strickland, Elizabeth A.

    2012-01-01

    The medial olivocochlear reflex (MOCR) has been hypothesized to provide benefit for listening in noise. Strong physiological support for an anti-masking role for the MOCR has come from the observation that auditory nerve (AN) fibers exhibit reduced firing to sustained noise and increased sensitivity to tones when the MOCR is elicited. The present study extended a well-established computational model for normal-hearing and hearing-impaired AN responses to demonstrate that these anti-masking ef...

  6. A Phenomenological Model of the Electrically Stimulated Auditory Nerve Fiber: Temporal and Biphasic Response Properties.

    Science.gov (United States)

    Horne, Colin D F; Sumner, Christian J; Seeber, Bernhard U

    2016-01-01

    We present a phenomenological model of electrically stimulated auditory nerve fibers (ANFs). The model reproduces the probabilistic and temporal properties of the ANF response to both monophasic and biphasic stimuli, in isolation. The main contribution of the model lies in its ability to reproduce statistics of the ANF response (mean latency, jitter, and firing probability) under both monophasic and cathodic-anodic biphasic stimulation, without changing the model's parameters. The response statistics of the model depend on stimulus level and duration of the stimulating pulse, reproducing trends observed in the ANF. In the case of biphasic stimulation, the model reproduces the effects of pseudomonophasic pulse shapes and also the dependence on the interphase gap (IPG) of the stimulus pulse, an effect that is quantitatively reproduced. The model is fitted to ANF data using a procedure that uniquely determines each model parameter. It is thus possible to rapidly parameterize a large population of neurons to reproduce a given set of response statistic distributions. Our work extends the stochastic leaky integrate and fire (SLIF) neuron, a well-studied phenomenological model of the electrically stimulated neuron. We extend the SLIF neuron so as to produce a realistic latency distribution by delaying the moment of spiking. During this delay, spiking may be abolished by anodic current. By this means, the probability of the model neuron responding to a stimulus is reduced when a trailing phase of opposite polarity is introduced. By introducing a minimum wait period that must elapse before a spike may be emitted, the model is able to reproduce the differences in the threshold level observed in the ANF for monophasic and biphasic stimuli. Thus, the ANF response to a large variety of pulse shapes are reproduced correctly by this model.

  7. Modeling the anti-masking effects of the olivocochlear reflex in auditory nerve responses to tones in sustained noise.

    Science.gov (United States)

    Chintanpalli, Ananthakrishna; Jennings, Skyler G; Heinz, Michael G; Strickland, Elizabeth A

    2012-04-01

    The medial olivocochlear reflex (MOCR) has been hypothesized to provide benefit for listening in noise. Strong physiological support for an anti-masking role for the MOCR has come from the observation that auditory nerve (AN) fibers exhibit reduced firing to sustained noise and increased sensitivity to tones when the MOCR is elicited. The present study extended a well-established computational model for normal-hearing and hearing-impaired AN responses to demonstrate that these anti-masking effects can be accounted for by reducing outer hair cell (OHC) gain, which is a primary effect of the MOCR. Tone responses in noise were examined systematically as a function of tone level, noise level, and OHC gain. Signal detection theory was used to predict detection and discrimination for different spontaneous rate fiber groups. Decreasing OHC gain decreased the sustained noise response and increased maximum discharge rate to the tone, thus modeling the ability of the MOCR to decompress AN fiber rate-level functions. Comparing the present modeling results with previous data from AN fibers in decerebrate cats suggests that the ipsilateral masking noise used in the physiological study may have elicited up to 20 dB of OHC gain reduction in addition to that inferred from the contralateral noise effects. Reducing OHC gain in the model also extended the dynamic range for discrimination over a wide range of background noise levels. For each masker level, an optimal OHC gain reduction was predicted (i.e., where maximum discrimination was achieved without increased detection threshold). These optimal gain reductions increased with masker level and were physiologically realistic. Thus, reducing OHC gain can improve tone-in-noise discrimination even though it may produce a “hearing loss” in quiet. Combining MOCR effects with the sensorineural hearing loss effects already captured by this computational AN model will be beneficial for exploring the implications of their interaction

  8. Recovery characteristics of the electrically stimulated auditory nerve in deafened guinea pigs : Relation to neuronal status

    NARCIS (Netherlands)

    Ramekers, Dyan; Versnel, Huib; Strahl, Stefan B.; Klis, Sjaak F L; Grolman, Wilko

    2015-01-01

    Successful cochlear implant performance requires adequate responsiveness of the auditory nerve to prolonged pulsatile electrical stimulation. Degeneration of the auditory nerve as a result of severe hair cell loss could considerably compromise this ability. The main objective of this study was to ch

  9. Suppression Measured from Chinchilla Auditory-Nerve-Fiber Responses Following Noise-Induced Hearing Loss: Adaptive-Tracking and Systems-Identification Approaches.

    Science.gov (United States)

    Sayles, Mark; Walls, Michael K; Heinz, Michael G

    2016-01-01

    The compressive nonlinearity of cochlear signal transduction, reflecting outer-hair-cell function, manifests as suppressive spectral interactions; e.g., two-tone suppression. Moreover, for broadband sounds, there are multiple interactions between frequency components. These frequency-dependent nonlinearities are important for neural coding of complex sounds, such as speech. Acoustic-trauma-induced outer-hair-cell damage is associated with loss of nonlinearity, which auditory prostheses attempt to restore with, e.g., "multi-channel dynamic compression" algorithms.Neurophysiological data on suppression in hearing-impaired (HI) mammals are limited. We present data on firing-rate suppression measured in auditory-nerve-fiber responses in a chinchilla model of noise-induced hearing loss, and in normal-hearing (NH) controls at equal sensation level. Hearing-impaired (HI) animals had elevated single-fiber excitatory thresholds (by ~ 20-40 dB), broadened frequency tuning, and reduced-magnitude distortion-product otoacoustic emissions; consistent with mixed inner- and outer-hair-cell pathology. We characterized suppression using two approaches: adaptive tracking of two-tone-suppression threshold (62 NH, and 35 HI fibers), and Wiener-kernel analyses of responses to broadband noise (91 NH, and 148 HI fibers). Suppression-threshold tuning curves showed sensitive low-side suppression for NH and HI animals. High-side suppression thresholds were elevated in HI animals, to the same extent as excitatory thresholds. We factored second-order Wiener-kernels into excitatory and suppressive sub-kernels to quantify the relative strength of suppression. We found a small decrease in suppression in HI fibers, which correlated with broadened tuning. These data will help guide novel amplification strategies, particularly for complex listening situations (e.g., speech in noise), in which current hearing aids struggle to restore intelligibility. PMID:27080669

  10. Auditory nerve synapses persist in ventral cochlear nucleus long after loss of acoustic input in mice with early-onset progressive hearing loss.

    Science.gov (United States)

    McGuire, Brian; Fiorillo, Benjamin; Ryugo, David K; Lauer, Amanda M

    2015-04-24

    Perceptual performance in persons with hearing loss, especially those using devices to restore hearing, is not fully predicted by traditional audiometric measurements designed to evaluate the status of peripheral function. The integrity of auditory brainstem synapses may vary with different forms of hearing loss, and differential effects on the auditory nerve-brain interface may have particularly profound consequences for the transfer of sound from ear to brain. Loss of auditory nerve synapses in ventral cochlear nucleus (VCN) has been reported after acoustic trauma, ablation of the organ of Corti, and administration of ototoxic compounds. The effects of gradually acquired forms deafness on these synapses are less well understood. We investigated VCN gross morphology and auditory nerve synapse integrity in DBA/2J mice with early-onset progressive sensorineural hearing loss. Hearing status was confirmed using auditory brainstem response audiometry and acoustic startle responses. We found no change in VCN volume, number of macroneurons, or number of VGLUT1-positive auditory nerve terminals between young adult and older, deaf DBA/2J. Cell-type specific analysis revealed no difference in the number of VGLUT1 puncta contacting bushy and multipolar cell body profiles, but the terminals were smaller in deaf DBA/2J mice. Transmission electron microscopy confirmed the presence of numerous healthy, vesicle-filled auditory nerve synapses in older, deaf DBA/2J mice. The present results suggest that synapses can be preserved over a relatively long time-course in gradually acquired deafness. Elucidating the mechanisms supporting survival of central auditory nerve synapses in models of acquired deafness may reveal new opportunities for therapeutic intervention. PMID:25686750

  11. The auditory nerve overlapped waveform (ANOW): A new objective measure of low-frequency hearing

    Science.gov (United States)

    Lichtenhan, Jeffery T.; Salt, Alec N.; Guinan, John J.

    2015-12-01

    One of the most pressing problems today in the mechanics of hearing is to understand the mechanical motions in the apical half of the cochlea. Almost all available measurements from the cochlear apex of basilar membrane or other organ-of-Corti transverse motion have been made from ears where the health, or sensitivity, in the apical half of the cochlea was not known. A key step in understanding the mechanics of the cochlear base was to trust mechanical measurements only when objective measures from auditory-nerve compound action potentials (CAPs) showed good preparation sensitivity. However, such traditional objective measures are not adequate monitors of cochlear health in the very low-frequency regions of the apex that are accessible for mechanical measurements. To address this problem, we developed the Auditory Nerve Overlapped Waveform (ANOW) that originates from auditory nerve output in the apex. When responses from the round window to alternating low-frequency tones are averaged, the cochlear microphonic is canceled and phase-locked neural firing interleaves in time (i.e., overlaps). The result is a waveform that oscillates at twice the probe frequency. We have demonstrated that this Auditory Nerve Overlapped Waveform - called ANOW - originates from auditory nerve fibers in the cochlear apex [8], relates well to single-auditory-nerve-fiber thresholds, and can provide an objective estimate of low-frequency sensitivity [7]. Our new experiments demonstrate that ANOW is a highly sensitive indicator of apical cochlear function. During four different manipulations to the scala media along the cochlear spiral, ANOW amplitude changed when either no, or only small, changes occurred in CAP thresholds. Overall, our results demonstrate that ANOW can be used to monitor cochlear sensitivity of low-frequency regions during experiments that make apical basilar membrane motion measurements.

  12. Deafness in cochlear and auditory nerve disorders.

    Science.gov (United States)

    Hopkins, Kathryn

    2015-01-01

    Sensorineural hearing loss is the most common type of hearing impairment worldwide. It arises as a consequence of damage to the cochlea or auditory nerve, and several structures are often affected simultaneously. There are many causes, including genetic mutations affecting the structures of the inner ear, and environmental insults such as noise, ototoxic substances, and hypoxia. The prevalence increases dramatically with age. Clinical diagnosis is most commonly accomplished by measuring detection thresholds and comparing these to normative values to determine the degree of hearing loss. In addition to causing insensitivity to weak sounds, sensorineural hearing loss has a number of adverse perceptual consequences, including loudness recruitment, poor perception of pitch and auditory space, and difficulty understanding speech, particularly in the presence of background noise. The condition is usually incurable; treatment focuses on restoring the audibility of sounds made inaudible by hearing loss using either hearing aids or cochlear implants.

  13. Recovery characteristics of the electrically stimulated auditory nerve in deafened guinea pigs: relation to neuronal status.

    Science.gov (United States)

    Ramekers, Dyan; Versnel, Huib; Strahl, Stefan B; Klis, Sjaak F L; Grolman, Wilko

    2015-03-01

    Successful cochlear implant performance requires adequate responsiveness of the auditory nerve to prolonged pulsatile electrical stimulation. Degeneration of the auditory nerve as a result of severe hair cell loss could considerably compromise this ability. The main objective of this study was to characterize the recovery of the electrically stimulated auditory nerve, as well as to evaluate possible changes caused by deafness-induced degeneration. To this end we studied temporal responsiveness of the auditory nerve in a guinea pig model of sensorineural hearing loss. Using masker-probe and pulse train paradigms we compared electrically evoked compound action potentials (eCAPs) in normal-hearing animals with those in animals with moderate (two weeks after ototoxic treatment) and severe (six weeks after ototoxic treatment) loss of spiral ganglion cells (SGCs). Masker-probe interval and pulse train inter-pulse interval was varied from 0.3 to 16 ms. Whereas recovery assessed with masker-probe was roughly similar for normal-hearing and both groups of deafened animals, it was considerably faster for six weeks deaf animals (τ ≈ 1.2 ms) than for two weeks deaf or normal-hearing animals (τ ≈ 3-4 ms) when 100-ms pulse trains were applied. Latency increased with decreasing inter-pulse intervals, and this was more pronounced with pulse trains than with masker-probe stimulation. With high frequency pulse train stimulation eCAP amplitudes were modulated for deafened animals, meaning that amplitudes for odd pulse numbers were larger than for even pulses. The relative refractory period (τ) and the modulation depth of the eCAP amplitude for pulse trains, as well as the latency increase for both paradigms significantly correlated with quantified measures of auditory nerve degeneration (size and packing density of SGCs). In addition to these findings, separate masker-probe recovery functions for the eCAP N1 and N2 peaks displayed a robust non-monotonic or shoulder

  14. Trauma-induced auditory nerve degeneration due to cerebellopontine(CP) angle manipulations:clinical and experimental experience

    Institute of Scientific and Technical Information of China (English)

    Tetsuji Sekiya

    2004-01-01

    In order to investigate the pathophysiologic mechanisms responsible for trauma-induced hearing disturbances due to auditory nerve degeneration, we established for the first time a rat experimental model in which auditory nerve degeneration due to compression injury of the cerebellopontine (CP) angle portion of the auditory nerve can be quantitatively evaluated. In this paper, Ⅰ demonstrate our clinical experience in CP angle surgery and some of the results of our experiments performed onthis rat experimental model. Trauma-induced hearing loss in CP angle operations has long been regarded as a sort of unavoidable "natural course"and therefore hopeless.I believe that this pessimistic view should be challenged and changed through new approaches in scientific research.

  15. Cortical perfusion response to an electrical stimulation of the auditory nerve in profoundly deaf patients: Study with technetium-99m hexamethylpropylene amine oxime single photon emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Le Scao, Y.; Robier, A.; Beuter, P. (Centre Hospitalier Universitaire, 37 - Tours (France). Dept. of Otorhinolaryngology); Baulieu, J.L.; Pourcelot, L. (Centre Hospitalier Universitaire, 37 - Tours (France). Dept. of Nuclear Medicine)

    1992-04-01

    Brain activation procedures associated with single photon emission tomography (SPET) have recently been developed in healthy controls and diseased patients in order to help in their diagnosis and treatment. We investigated the effects of a promontory test (PT) on the cerebral distribution of technetium-99m hexamethyl-propylene amine oxime ({sup 99m}Tc-HMPAO) in 7 profoundly deaf patients, 6 PT+ and PT-. The count variation in the temporal lobe was calculated on 6 coronal slices using the ratio (R{sub stimulation}-R{sub deprivation})/R{sub deprivation} where R=counts in the temporal lobe was observed in all patients and was higher in all patients with PT+ than in the patient with PT-. The problems of head positioning and resolution of the system were taken into account, and we considered that the maximal count increment was related to the auditory cortex response to the stimulus. Further clinical investigations with high-resolution systems have to be performed in order to validate this presurgery test in cochlear implant assessment. (orig.).

  16. One-tone suppression in the frog auditory nerve

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Jørgensen, M B

    1996-01-01

    Sixty-seven fibers of a sample of 401 in the auditory nerve of grassfrogs (Rana temporaria) showed one-tone suppression, i.e., their spontaneous activity was suppressed by tones. All fibers were afferents from the amphibian papilla with best frequencies between 100 and 400 Hz. Best suppression...

  17. The Effect of Low Omega-3/Omega-6 Ratio on Auditory Nerve Conduction in Rat Pups.

    OpenAIRE

    Saeid Farahani; Masoud Motasaddi Zarandy; Gholamreza Hassanzadeh; Farzad Shidfar; Shohreh Jalaie; Vida Rahimi

    2015-01-01

    The biological effects of omega-3 and omega-6 fatty acids are determined by their mutual interactions. This interaction extremely affects various functions. Lower consumption of omega-3 during gestation leads to various disorders, even in hearing. We aimed to assess the effect of low omega-3/omega-6 ratios on auditory nerve conduction. In this experimental study, the auditory brainstem response test was performed on 24-day-old rat (n=14). The rats were divided into case (low omega-3/omega-6 r...

  18. Time course of dynamic range adaptation in the auditory nerve

    OpenAIRE

    Wen, Bo; Wang, Grace I.; Dean, Isabel; Delgutte, Bertrand

    2012-01-01

    Auditory adaptation to sound-level statistics occurs as early as in the auditory nerve (AN), the first stage of neural auditory processing. In addition to firing rate adaptation characterized by a rate decrement dependent on previous spike activity, AN fibers show dynamic range adaptation, which is characterized by a shift of the rate-level function or dynamic range toward the most frequently occurring levels in a dynamic stimulus, thereby improving the precision of coding of the most common ...

  19. Stimulation of the human auditory nerve with optical radiation

    Science.gov (United States)

    Fishman, Andrew; Winkler, Piotr; Mierzwinski, Jozef; Beuth, Wojciech; Izzo Matic, Agnella; Siedlecki, Zygmunt; Teudt, Ingo; Maier, Hannes; Richter, Claus-Peter

    2009-02-01

    A novel, spatially selective method to stimulate cranial nerves has been proposed: contact free stimulation with optical radiation. The radiation source is an infrared pulsed laser. The Case Report is the first report ever that shows that optical stimulation of the auditory nerve is possible in the human. The ethical approach to conduct any measurements or tests in humans requires efficacy and safety studies in animals, which have been conducted in gerbils. This report represents the first step in a translational research project to initiate a paradigm shift in neural interfaces. A patient was selected who required surgical removal of a large meningioma angiomatum WHO I by a planned transcochlear approach. Prior to cochlear ablation by drilling and subsequent tumor resection, the cochlear nerve was stimulated with a pulsed infrared laser at low radiation energies. Stimulation with optical radiation evoked compound action potentials from the human auditory nerve. Stimulation of the auditory nerve with infrared laser pulses is possible in the human inner ear. The finding is an important step for translating results from animal experiments to human and furthers the development of a novel interface that uses optical radiation to stimulate neurons. Additional measurements are required to optimize the stimulation parameters.

  20. Temporary Neurotrophin Treatment Prevents Deafness-Induced Auditory Nerve Degeneration and Preserves Function

    NARCIS (Netherlands)

    Ramekers, Dyan; Versnel, Huib; Strahl, Stefan B.; Klis, Sjaak F. L.; Grolman, Wilko

    2015-01-01

    After substantial loss of cochlear hair cells, exogenous neurotrophins prevent degeneration of the auditory nerve. Because cochlear implantation, the current therapy for profound sensorineural hearing loss, depends on a functional nerve, application of neurotrophins is being investigated. We address

  1. Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes’ hearing problem:an innovation in multi-channel-array skin-hearing technology

    Institute of Scientific and Technical Information of China (English)

    Jianwen Li; Yan Li; Ming Zhang; Weifang Ma; Xuezong Ma

    2014-01-01

    The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the ifltering principle of hair cells, external voice sig-nals at different frequencies are converted to current signals at corresponding frequencies using electronic multi-channel bandpass ifltering technology. Different positions on the skin can be stimulated by the electrode array, allowing the perception and discrimination of external speech signals to be determined by the skin response to the current signals. Through voice frequen-cy analysis, the frequency range of the band-pass iflter can also be determined. These ifndings demonstrate that the sensory nerves in the skin can help to transfer the voice signal and to dis-tinguish the speech signal, suggesting that the skin sensory nerves are good candidates for the replacement of the auditory nerve in addressing deaf-mutes’ hearing problems. Scientiifc hearing experiments can be more safely performed on the skin. Compared with the artificial cochlea, multi-channel-array skin-hearing aids have lower operation risk in use, are cheaper and are more easily popularized.

  2. Diffusion tensor imaging of the auditory nerve in patients with acquired single-sided deafness

    DEFF Research Database (Denmark)

    Vos, Sjoerd; Haakma, Wieke; Versnel, Huib;

    2015-01-01

    following cochlear hair cell loss, and the amount of degeneration may considerably differ between the two ears, also in patients with bilateral deafness. A measure that reflects the nerve's condition would help to assess the best of both nerves and decide accordingly which ear should be implanted...... DTI metrics from the deaf-sided with the healthy-sided nerves in patients showed no significant differences. There was a small but significant reduction in fractional anisotropy in both auditory nerves in patients compared with normal-hearing controls. These results are the first evidence of possible...... changes in the microstructure of the bilateral auditory nerves as a result of single-sided deafness. Our results also indicate that it is too early to assess the degenerative status of the auditory nerve of a subject-specific basis....

  3. Assessment and Preservation of Auditory Nerve Integrity in the Deafened Guinea Pig

    NARCIS (Netherlands)

    Ramekers, D.

    2014-01-01

    Profound hearing loss is often caused by cochlear hair cell loss. Cochlear implants (CIs) essentially replace hair cells by encoding sound and conveying the signal by means of pulsatile electrical stimulation to the spiral ganglion cells (SGCs) which form the auditory nerve. SGCs progressively degen

  4. Assessing the Firing Properties of the Electrically Stimulated Auditory Nerve Using a Convolution Model

    NARCIS (Netherlands)

    Strahl, Stefan B; Ramekers, Dyan; Nagelkerke, Marjolijn M B; Schwarz, Konrad E; Spitzer, Philipp; Klis, Sjaak F L; Grolman, Wilko; Versnel, Huib

    2016-01-01

    The electrically evoked compound action potential (eCAP) is a routinely performed measure of the auditory nerve in cochlear implant users. Using a convolution model of the eCAP, additional information about the neural firing properties can be obtained, which may provide relevant information about th

  5. Pulsed 808-nm infrared laser stimulation of the auditory nerve in guinea pig cochlea.

    Science.gov (United States)

    Xia, Nan; Wu, Xiao Y; Wang, Xing; Mou, Zong X; Wang, Man Q; Gu, Xin; Zheng, Xiao L; Hou, Wen S

    2014-01-01

    Pulsed near-infrared radiation has been proposed as an alternative stimulus for auditory nerve stimulation and could be potentially used in the design of cochlear implant. Although the infrared with high absorption coefficient of water (i.e., wavelength ranged from 1.8 to 2.2 μm) has been widely investigated, the lymph in the cochlea absorbs most of the infrared energies, and only a small part can arrive at the target auditory nerves. The present study is aimed to test whether the short-wavelength near-infrared irradiation with lower absorption coefficients can penetrate the lymph fluid to stimulate the auditory nerves. An 808-nm near-infrared laser was chosen to stimulate the auditory nerve in the guinea pig cochlea. The infrared pulse was delivered by an optical fiber that was surgically inserted near the round window membrane and oriented toward the spiral ganglion cells in the basal turn of the cochlea. The 2-Hz infrared pulses were used to stimulate the cochlea before and after the deafness with different pulse durations (100-1,000 μs). Optically evoked compound action potentials (oCAPs) were recorded during the infrared radiation. We successfully recorded oCAPs from both normal hearing animals and deafened animals. The oCAP amplitude increased with the infrared radiation energy. The preliminary experiment suggests that the near-infrared with lower absorption coefficients can effectively pass through the lymph filled in the cochlea and stimulate the auditory nerve. Further studies will optimize the deafness animal model and determine the optimal stimulation parameters.

  6. Auditory nerve representation of a complex communication sound in background noise.

    Science.gov (United States)

    Simmons, A M; Schwartz, J J; Ferragamo, M

    1992-05-01

    A population study of auditory nerve responses in the bullfrog, Rana catesbeiana, analyzed the relative contributions of spectral and temporal coding in representing a complex, species-specific communication signal at different stimulus intensities and in the presence of background noise. At stimulus levels of 70 and 80 dB SPL, levels which approximate that received during communication in the natural environment, average rate profiles plotted over fiber characteristic frequency do not reflect the detailed spectral fine structure of the synthetic call. Rate profiles do not change significantly in the presence of background noise. In ambient (no noise) and low noise conditions, both amphibian papilla and basilar papilla fibers phase lock strongly to the waveform periodicity (fundamental frequency) of the synthetic advertisement call. The higher harmonic spectral fine structure of the synthetic call is not accurately reflected in the timing of fiber firing, because firing is "captured" by the fundamental frequency. Only a small number of fibers synchronize preferentially to any harmonic in the call other than the first, and none synchronize to any higher than the third, even when fiber characteristic frequency is close to one of these higher harmonics. Background noise affects fiber temporal responses in two ways: It can reduce synchronization to the fundamental frequency, until fiber responses are masked; or it can shift synchronization from the fundamental to the second or third harmonic of the call. This second effect results in a preservation of temporal coding at high noise levels. These data suggest that bullfrog eighth nerve fibers extract the waveform periodicity of multiple-harmonic stimuli primarily by a temporal code.

  7. Polarity sensitivity of the electrically stimulated auditory nerve at different cochlear sites

    OpenAIRE

    Undurraga Lucero, Jaime; van Wieringen, Astrid; Carlyon, Robert P.; Macherey, Olivier; Wouters, Jan

    2009-01-01

    Commercially available cochlear implants (CIs) stimulate the auditory nerve (AN) using symmetric biphasic current (BP) pulses. However, recent data have shown that the use of asymmetric pulse shapes could be beneficial in terms of reducing power consumption, increasing dynamic range and limiting channel interactions. In these charge-balanced stimuli, the effectiveness of one phase (one polarity) is reduced by making it longer and lower in amplitude than the other. For the design of novel CI s...

  8. Assessing the Firing Properties of the Electrically Stimulated Auditory Nerve Using a Convolution Model.

    Science.gov (United States)

    Strahl, Stefan B; Ramekers, Dyan; Nagelkerke, Marjolijn M B; Schwarz, Konrad E; Spitzer, Philipp; Klis, Sjaak F L; Grolman, Wilko; Versnel, Huib

    2016-01-01

    The electrically evoked compound action potential (eCAP) is a routinely performed measure of the auditory nerve in cochlear implant users. Using a convolution model of the eCAP, additional information about the neural firing properties can be obtained, which may provide relevant information about the health of the auditory nerve. In this study, guinea pigs with various degrees of nerve degeneration were used to directly relate firing properties to nerve histology. The same convolution model was applied on human eCAPs to examine similarities and ultimately to examine its clinical applicability. For most eCAPs, the estimated nerve firing probability was bimodal and could be parameterised by two Gaussian distributions with an average latency difference of 0.4 ms. The ratio of the scaling factors of the late and early component increased with neural degeneration in the guinea pig. This ratio decreased with stimulation intensity in humans. The latency of the early component decreased with neural degeneration in the guinea pig. Indirectly, this was observed in humans as well, assuming that the cochlear base exhibits more neural degeneration than the apex. Differences between guinea pigs and humans were observed, among other parameters, in the width of the early component: very robust in guinea pig, and dependent on stimulation intensity and cochlear region in humans. We conclude that the deconvolution of the eCAP is a valuable addition to existing analyses, in particular as it reveals two separate firing components in the auditory nerve.

  9. Effects on auditory-nerve fibers of opening the otic capsule at the apex of the chinchilla cochlea

    Science.gov (United States)

    Recio-Spinoso, Alberto; Temchin, Andrei N.; Ruggero, Mario A.

    2015-12-01

    Vibration responses to clicks measured at the apex of chinchilla cochleae with open otic capsules have onsets much shorter than those of responses of auditory-nerve fibers (ANFs) corrected for synaptic and neural delays. Apical vibration responses to tones in open cochleae also differ in other respects from the responses to tones of ANFs with low characteristic frequency (CF) in normal chinchilla cochleae. To further specify the origin(s) of these differences, we recorded from chinchilla ANFs after delicately opening a small hole in the otic capsule overlying scala vestibuli in the cochlear apex. In those cochleae, the earliest ANF responses to clicks are often evoked by condensation (rather than rarefaction) clicks and responses to tones often exhibit level-dependent phase changes different from those in normal cochleae. These findings are largely consistent with, and seem to account for, apical vibration responses of cochleae with open otic capsules. An unexpected finding is that the tuning curves of ANFs with moderately high CF and normal CF thresholds often had hypersensitive tails.

  10. Fast negative feedback enables mammalian auditory nerve fibers to encode a wide dynamic range of sound intensities.

    Directory of Open Access Journals (Sweden)

    Mark Ospeck

    Full Text Available Mammalian auditory nerve fibers (ANF are remarkable for being able to encode a 40 dB, or hundred fold, range of sound pressure levels into their firing rate. Most of the fibers are very sensitive and raise their quiescent spike rate by a small amount for a faint sound at auditory threshold. Then as the sound intensity is increased, they slowly increase their spike rate, with some fibers going up as high as ∼300 Hz. In this way mammals are able to combine sensitivity and wide dynamic range. They are also able to discern sounds embedded within background noise. ANF receive efferent feedback, which suggests that the fibers are readjusted according to the background noise in order to maximize the information content of their auditory spike trains. Inner hair cells activate currents in the unmyelinated distal dendrites of ANF where sound intensity is rate-coded into action potentials. We model this spike generator compartment as an attenuator that employs fast negative feedback. Input current induces rapid and proportional leak currents. This way ANF are able to have a linear frequency to input current (f-I curve that has a wide dynamic range. The ANF spike generator remains very sensitive to threshold currents, but efferent feedback is able to lower its gain in response to noise.

  11. Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei

    DEFF Research Database (Denmark)

    Tang, Y. Z.; Christensen-Dalsgaard, J.; Carr, C. E.

    2012-01-01

    We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of low...

  12. Cutaneous sensory nerve as a substitute for auditory nerve in solving deaf-mutes’ hearing problem: an innovation in multi-channel-array skin-hearing technology

    OpenAIRE

    Li, Jianwen; Li, Yan; Zhang, Ming; Ma, Weifang; Ma, Xuezong

    2014-01-01

    The current use of hearing aids and artificial cochleas for deaf-mute individuals depends on their auditory nerve. Skin-hearing technology, a patented system developed by our group, uses a cutaneous sensory nerve to substitute for the auditory nerve to help deaf-mutes to hear sound. This paper introduces a new solution, multi-channel-array skin-hearing technology, to solve the problem of speech discrimination. Based on the filtering principle of hair cells, external voice signals at different...

  13. Evaluation of peripheral compression and auditory nerve fiber intensity coding using auditory steady-state responses

    DEFF Research Database (Denmark)

    Encina Llamas, Gerard; M. Harte, James; Epp, Bastian

    2015-01-01

    . Evaluation of these properties provides information about the health state of the system. It has been shown that a loss of outer hair cells leads to a reduction in peripheral compression. It has also recently been shown in animal studies that noise over-exposure, producing temporary threshold shifts, can......The compressive nonlinearity of the auditory system is assumed to be an epiphenomenon of a healthy cochlea and, particularly, of outer-hair cell function. Another ability of the healthy auditory system is to enable communication in acoustical environments with high-level background noises...

  14. Basic response characteristics of auditory nerve fibers in the grassfrog (Rana temporaria)

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, J; Jørgensen, M B; Kanneworff, M

    1998-01-01

    phasic cells giving one spike per stimulation. Therefore, the mechanism underlying PS is probably different from that underlying adaptation. The sharpening of the neural encoding of temporal parameters and the strong encoding of sound offset as well as onset caused by PS very likely is biologically...

  15. Target-specific regulation of presynaptic release properties at auditory nerve terminals in the avian cochlear nucleus.

    Science.gov (United States)

    Ahn, J; MacLeod, K M

    2016-03-01

    Short-term synaptic plasticity (STP) acts as a time- and firing rate-dependent filter that mediates the transmission of information across synapses. In the auditory brain stem, the divergent pathways that encode acoustic timing and intensity information express differential STP. To investigate what factors determine the plasticity expressed at different terminals, we tested whether presynaptic release probability differed in the auditory nerve projections to the two divisions of the avian cochlear nucleus, nucleus angularis (NA) and nucleus magnocellularis (NM). Estimates of release probability were made with an open-channel blocker ofN-methyl-d-aspartate (NMDA) receptors. Activity-dependent blockade of NMDA receptor-mediated excitatory postsynaptic currents (EPSCs) with application of 20 μM (+)-MK801 maleate was more rapid in NM than in NA, indicating that release probability was significantly higher at terminals in NM. Paired-pulse ratio (PPR) was tightly correlated with the blockade rate at terminals in NA, suggesting that PPR was a reasonable proxy for relative release probability at these synapses. To test whether release probability was similar across convergent inputs onto NA neurons, PPRs of different nerve inputs onto the same postsynaptic NA target neuron were measured. The PPRs, as well as the plasticity during short trains, were tightly correlated across multiple inputs, further suggesting that release probability is coordinated at auditory nerve terminals in a target-specific manner. This highly specific regulation of STP in the auditory brain stem provides evidence that the synaptic dynamics are tuned to differentially transmit the auditory information in nerve activity into parallel ascending pathways. PMID:26719087

  16. 人工耳蜗植入前电刺激听神经复合动作电位检测方法的建立和初步应用%The Establishment and Application of Electrically Evoked Auditory Nerve Compound Action Potential Test Method before Cochlear Implantation

    Institute of Scientific and Technical Information of China (English)

    王斌; 曹克利; 魏朝刚; 王轶; 路远

    2012-01-01

    cochlear malformation. After the success of anesthesia, all the patients' tympani bands were generally opened and the multi-channel test electrodes were placed into the tympani bands. The electrodes were connected to the Cochlear speech processor and electrical stimulation generator via the computer. By the Custom Sound EP 2.0 software, the stimulation parameters were adjusted and optimized to perform neural response telemetry (NRT) test. The stimulation intensity decreased or increased by 5 CL gradually until to the threshold. The ECAP waveforms and thresholds were automatically recorded when giving electrical stimulation pulses. After cochlear implantation, the NRT was regularly performed to record ECAP waveforms and thresholds. One month later, the T and C values of mapping were tested after switch-on. The correlation between the ECAP thresholds of the two electrodes and the C values of switch-on were statistically analyzed. Results The presences of ECAP by test electrodes and commercial electrodes were both 90% and the average thresholds were (160.50 ± 15.12) CL and (160.00±11.27) CL respectively, showing no significant difference (P>0.05). The thresholds were related to the C values after witch-on (177.40±10.61) (R2=0.844,r=0.919). Conclusion Through this study, an ECAP test method before cochlear implantation has been successfully developed. The ECAP can provide reliable and effective information about the auditory nerve responses in patients with inner ear and /or auditory pathway abnormalities and no residual hearing. This is useful in evaluating the development of auditory system and predicting the postoperative rehabilitation outcome of the patients.

  17. Electrical stimulation of the auditory nerve: the coding of frequency, the perception of pitch and the development of cochlear implant speech processing strategies for profoundly deaf people.

    Science.gov (United States)

    Clark, G M

    1996-09-01

    1. The development of speech processing strategies for multiple-channel cochlear implants has depended on encoding sound frequencies and intensities as temporal and spatial patterns of electrical stimulation of the auditory nerve fibres so that speech information of most importance of intelligibility could be transmitted. 2. Initial physiological studies showed that rate encoding of electrical stimulation above 200 pulses/s could not reproduce the normal response patterns in auditory neurons for acoustic stimulation in the speech frequency range above 200 Hz and suggested that place coding was appropriate for the higher frequencies. 3. Rate difference limens in the experimental animal were only similar to those for sound up to 200 Hz. 4. Rate difference limens in implant patients were similar to those obtained in the experimental animal. 5. Satisfactory rate discrimination could be made for durations of 50 and 100 ms, but not 25 ms. This made rate suitable for encoding longer duration suprasegmental speech information, but not segmental information, such as consonants. The rate of stimulation could also be perceived as pitch, discriminated at different electrode sites along the cochlea and discriminated for stimuli across electrodes. 6. Place pitch could be scaled according to the site of stimulation in the cochlea so that a frequency scale was preserved and it also had a different quality from rate pitch and was described as tonality. Place pitch could also be discriminated for the shorter durations (25 ms) required for identifying consonants. 7. The inaugural speech processing strategy encoded the second formant frequencies (concentrations of frequency energy in the mid frequency range of most importance for speech intelligibility) as place of stimulation, the voicing frequency as rate of stimulation and the intensity as current level. Our further speech processing strategies have extracted additional frequency information and coded this as place of stimulation

  18. Periodicity extraction in the anuran auditory nerve. II: Phase and temporal fine structure.

    Science.gov (United States)

    Simmons, A M; Reese, G; Ferragamo, M

    1993-06-01

    Discharge patterns of single eighth nerve fibers in the bullfrog, Rana catesbeiana, were analyzed in response to signals consisting of multiple harmonics of a common, low-amplitude fundamental frequency. The signals were chosen to reflect the frequency and amplitude spectrum of the bullfrog's species-specific advertisement call. The phase spectrum of the signals was manipulated to produce envelopes that varied in their shapes from impulselike (sharp) to noiselike (flattened). Peripheral responses to these signals were analyzed by computing the autocorrelation functions of the spike trains and their power spectra, as well as by constructing period histograms over the time intervals of the low-frequency harmonics. In response to a phase aligned signal with an impulsive envelope, most fibers, regardless of their characteristic frequencies or place of origin within the inner ear, synchronize to the fundamental frequency of the signal. The temporal patterns of fiber discharge to these stimuli are not typically captured by that stimulus harmonic closet to the fiber characteristic frequency, as would be expected from a spectral coding mechanism for periodicity extraction, but instead directly reflect the periodicity of the stimulus envelope. Changing the phase relations between the individual harmonics constituting the signal produces changes in temporal discharge patterns of some fibers by shifting predominant synchronization away from the fundamental frequency to the low-frequency spectral peak in the complex stimuli. The proportion of fibers whose firing is captured by the fundamental frequency decreases as the waveform envelope becomes less impulselike. Fiber characteristic frequency is not highly correlated with the harmonic number to which synchronization is strongest. The higher-harmonic spectral fine structure of the signals is not reflected in fiber temporal response, regardless of the shape of the stimulus envelope, even for those harmonics within the range of

  19. Improved Auditory Nerve Survival with Nanoengineered Supraparticles for Neurotrophin Delivery into the Deafened Cochlea

    Science.gov (United States)

    Tan, Justin; Wang, Yajun; Caruso, Frank; Shepherd, Robert K.

    2016-01-01

    Cochlear implants electrically stimulate spiral ganglion neurons (SGNs) in order to provide speech cues to severe-profoundly deaf patients. In normal hearing cochleae the SGNs depend on endogenous neurotrophins secreted by sensory cells in the organ of Corti for survival. SGNs gradually degenerate following deafness and consequently there is considerable interest in developing clinically relevant strategies to provide exogenous neurotrophins to preserve SGN survival. The present study investigated the safety and efficacy of a drug delivery system for the cochlea using nanoengineered silica supraparticles. In the present study we delivered Brain-derived neurotrophic factor (BDNF) over a period of four weeks and evaluated SGN survival as a measure of efficacy. Supraparticles were bilaterally implanted into the basal turn of cochleae in profoundly deafened guinea pigs. One ear received BDNF-loaded supraparticles and the other ear control (unloaded) supraparticles. After one month of treatment the cochleae were examined histologically. There was significantly greater survival of SGNs in cochleae that received BDNF supraparticles compared to the contralateral control cochleae (repeated measures ANOVA, p = 0.009). SGN survival was observed over a wide extent of the cochlea. The supraparticles were well tolerated within the cochlea with a tissue response that was localised to the site of implantation in the cochlear base. Although mild, the tissue response was significantly greater in cochleae treated with BDNF supraparticles compared to the controls (repeated measures ANOVA, p = 0.003). These data support the clinical potential of this technology particularly as the supraparticles can be loaded with a variety of therapeutic drugs. PMID:27788219

  20. BDNF Increases Survival and Neuronal Differentiation of Human Neural Precursor Cells Cotransplanted with a Nanofiber Gel to the Auditory Nerve in a Rat Model of Neuronal Damage

    Directory of Open Access Journals (Sweden)

    Yu Jiao

    2014-01-01

    Full Text Available Objectives. To study possible nerve regeneration of a damaged auditory nerve by the use of stem cell transplantation. Methods. We transplanted HNPCs to the rat AN trunk by the internal auditory meatus (IAM. Furthermore, we studied if addition of BDNF affects survival and phenotypic differentiation of the grafted HNPCs. A bioactive nanofiber gel (PA gel, in selected groups mixed with BDNF, was applied close to the implanted cells. Before transplantation, all rats had been deafened by a round window niche application of β-bungarotoxin. This neurotoxin causes a selective toxic destruction of the AN while keeping the hair cells intact. Results. Overall, HNPCs survived well for up to six weeks in all groups. However, transplants receiving the BDNF-containing PA gel demonstrated significantly higher numbers of HNPCs and neuronal differentiation. At six weeks, a majority of the HNPCs had migrated into the brain stem and differentiated. Differentiated human cells as well as neurites were observed in the vicinity of the cochlear nucleus. Conclusion. Our results indicate that human neural precursor cells (HNPC integration with host tissue benefits from additional brain derived neurotrophic factor (BDNF treatment and that these cells appear to be good candidates for further regenerative studies on the auditory nerve (AN.

  1. Predictable response from MCR operators

    International Nuclear Information System (INIS)

    Operating Philosophy in a nuclear power plant is the driving influence that leads to obtaining a predictable response to any operating challenge in the Main Control Room. This means that for any event or abnormal situation in the plant, every operator will take the unit to the required state, every time. This is a must in our industry. This can be achieved by clearly identifying the challenges that face the operating staff. It is essential that a balanced review be done so that there is not over emphasis on any aspect of the operator's ability to respond. The major areas discussed in this presentation are Plant, Procedures and People. Discussion will bring focus to the use of procedures and how to identify good practices that require reinforcement at the simulator, and how to identify potential vulnerabilities. The three overheads will be reviewed to illustrate the systematic approach used at Darlington Nuclear. (author)

  2. Modeling auditory evoked brainstem responses to transient stimuli

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Dau, Torsten; Harte, James;

    2012-01-01

    A quantitative model is presented that describes the formation of auditory brainstem responses (ABR) to tone pulses, clicks and rising chirps as a function of stimulation level. The model computes the convolution of the instantaneous discharge rates using the “humanized” nonlinear auditory-nerve ...

  3. Caregiver Responsiveness to the Family Bereavement Program: What predicts responsiveness? What does responsiveness predict?

    OpenAIRE

    Schoenfelder, Erin N.; Sandler, Irwin N.; Millsap, Roger E.; Wolchik, Sharlene A.; Berkel, Cady; Ayers, Timothy S.

    2013-01-01

    The study developed a multi-dimensional measure to assess participant responsiveness to a preventive intervention, and applied this measure to study how participant baseline characteristics predict responsiveness and how responsiveness predicts program outcomes. The study was conducted with caregivers who participated in the parenting-focused component of the Family Bereavement Program (FBP), a prevention program for families that have experienced parental death. The sample consisted of 89 ca...

  4. Predicting responses in multiple environments

    NARCIS (Netherlands)

    Malosetti Zunin, Marcos; Bustos-Korts, Daniela; Boer, Martin P.; Eeuwijk, van Fred A.

    2016-01-01

    Prediction of the phenotypes for a set of genotypes across multiple environments is a fundamental task in any plant breeding program. Genomic prediction (GP) can assist selection decisions by combining incomplete phenotypic information over multiple environments (MEs) with dense sets of markers.

  5. Predicting responses from Rasch measures.

    Science.gov (United States)

    Linacre, John M

    2010-01-01

    There is a growing family of Rasch models for polytomous observations. Selecting a suitable model for an existing dataset, estimating its parameters and evaluating its fit is now routine. Problems arise when the model parameters are to be estimated from the current data, but used to predict future data. In particular, ambiguities in the nature of the current data, or overfit of the model to the current dataset, may mean that better fit to the current data may lead to worse fit to future data. The predictive power of several Rasch and Rasch-related models are discussed in the context of the Netflix Prize. Rasch-related models are proposed based on Singular Value Decomposition (SVD) and Boltzmann Machines.

  6. Predicting response to epigenetic therapy

    DEFF Research Database (Denmark)

    Treppendahl, Marianne B; Sommer Kristensen, Lasse; Grønbæk, Kirsten

    2014-01-01

    Drugs targeting the epigenome are new promising cancer treatment modalities; however, not all patients receive the same benefit from these drugs. In contrast to conventional chemotherapy, responses may take several months after the initiation of treatment to occur. Accordingly, identification of ......-approved epigenetic drugs....

  7. Prediction of treatment response to adalimumab

    DEFF Research Database (Denmark)

    Krintel, Sophine B; Dehlendorff, C; Hetland, M L;

    2016-01-01

    At least 30% of patients with rheumatoid arthritis (RA) do not respond to biologic agents, which emphasizes the need of predictive biomarkers. We aimed to identify microRNAs (miRNAs) predictive of response to adalimumab in 180 treatment-naïve RA patients enrolled in the OPtimized treatment...

  8. Predicting and measuring fluid responsiveness with echocardiography

    Directory of Open Access Journals (Sweden)

    Ashley Miller

    2016-06-01

    Full Text Available Echocardiography is ideally suited to guide fluid resuscitation in critically ill patients. It can be used to assess fluid responsiveness by looking at the left ventricle, aortic outflow, inferior vena cava and right ventricle. Static measurements and dynamic variables based on heart–lung interactions all combine to predict and measure fluid responsiveness and assess response to intravenous fluid esuscitation. Thorough knowledge of these variables, the physiology behind them and the pitfalls in their use allows the echocardiographer to confidently assess these patients and in combination with clinical judgement manage them appropriately.

  9. Cochlear Responses and Auditory Brainstem Response Functions in Adults with Auditory Neuropathy/ Dys-Synchrony and Individuals with Normal Hearing

    Directory of Open Access Journals (Sweden)

    Zahra Jafari

    2007-06-01

    Full Text Available Background and Aim: Physiologic measures of cochlear and auditory nerve function may be of assis¬tance in distinguishing between hearing disorders due primarily to auditory nerve impairment from those due primarily to cochlear hair cells dysfunction. The goal of present study was to measure of co-chlear responses (otoacoustic emissions and cochlear microphonics and auditory brainstem response in some adults with auditory neuropathy/ dys-synchrony and subjects with normal hearing. Materials and Methods: Patients were 16 adults (32 ears in age range of 14-30 years with auditory neu¬ropathy/ dys-synchrony and 16 individuals in age range of 16-30 years from both sexes. The results of transient otoacoustic emissions, cochlear microphonics and auditory brainstem response measures were compared in both groups and the effects of age, sex, ear and degree of hearing loss were studied. Results: The pure-tone average was 48.1 dB HL in auditory neuropathy/dys-synchrony group and the fre¬quency of low tone loss and flat audiograms were higher among other audiogram's shapes. Transient oto¬acoustic emissions were shown in all auditory neuropathy/dys-synchrony people except two cases and its average was near in both studied groups. The latency and amplitude of the biggest reversed co-chlear microphonics response were higher in auditory neuropathy/dys-synchrony patients than control peo¬ple significantly. The correlation between cochlear microphonics amplitude and degree of hearing loss was not significant, and age had significant effect in some cochlear microphonics measures. Audi-tory brainstem response had no response in auditory neuropathy/dys-synchrony patients even with low stim¬uli rates. Conclusion: In adults with speech understanding worsen than predicted from the degree of hearing loss that suspect to auditory neuropathy/ dys-synchrony, the frequency of low tone loss and flat audiograms are higher. Usually auditory brainstem response is absent in

  10. Clinical predictive factors of pathologic tumor response

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chi Hwan; Kim, Won Dong; Lee, Sang Jeon; Park, Woo Yoon [Chungbuk National University College of Medicine, Cheongju (Korea, Republic of)

    2012-09-15

    The aim of this study was to identify clinical predictive factors for tumor response after preoperative chemoradiotherapy (CRT) in rectal cancer. The study involved 51 patients who underwent preoperative CRT followed by surgery between January 2005 and February 2012. Radiotherapy was delivered to the whole pelvis at a dose of 45 Gy in 25 fractions, followed by a boost of 5.4 Gy in 3 fractions to the primary tumor with 5 fractions per week. Three different chemotherapy regimens were used. Tumor responses to preoperative CRT were assessed in terms of tumor downstaging and pathologic complete response (ypCR). Statistical analyses were performed to identify clinical factors associated with pathologic tumor response. Tumor downstaging was observed in 28 patients (54.9%), whereas ypCR was observed in 6 patients (11.8%). Multivariate analysis found that predictors of downstaging was pretreatment relative lymphocyte count (p = 0.023) and that none of clinical factors was significantly associated with ypCR. Pretreatment relative lymphocyte count (%) has a significant impact on the pathologic tumor response (tumor downstaging) after preoperative CRT for locally advanced rectal cancer. Enhancement of lymphocyte-mediated immune reactions may improve the effect of preoperative CRT for rectal cancer.

  11. Towards prediction and modulation of treatment response

    International Nuclear Information System (INIS)

    The purpose of this paper is to evaluate new predictive assays and their potential to modulate treatment response. Their impact is presented in the context of three EORTC clinical trials in head and neck, lung and breast cancer, showing an improvement in survival by accelerated fractionation, concomitant use of cisplatin and radiotherapy and adjuvant hormonal treatment, respectively. Assays have been developed to predict the response to treatment by measuring tumor characteristics, such as the growth potential by the labeling index after i.v. injection of IdUrd, the extent of radiation-induced stable and unstable chromosome aberrations and the induction of apoptosis. These assays could guide us in the adaptation of the individual radiation doses and fractionation schedules. The measurement of the effect of cisplatin on DNA has become feasible with the development of antibodies against DNA adducts. In a recently completed phase II dose escalation trial with concomitant radiotherapy and daily cisplatin in lung cancer, we found that patients with high DNA adduct levels measured in the buccal mucosa, had a much better survival rate than patients with a low or undetectable amount of cisplatin DNA adducts. A better understanding of the signal transduction pathways involved in radiation-induced apoptosis may help to design studies aimed at modulating the apoptotic response. We and others have recently shown that alkylphospholipids, which inhibit mitogenic signaling, induce apoptosis in a variety of tumor cell lines. In combination with ionizing radiation, these compounds cause an enhancement of apoptotic cell kill. This type of signaling-based intervention study may form the basis for new therapeutic strategies. Pretreatment levels of apoptosis may be helpful in predicting treatment outcome, although the data so far show inconsistent results. The importance of evaluating other tumor-biological parameters, including cell kinetics should be stressed. Based on assays

  12. Prediction of psilocybin response in healthy volunteers.

    Directory of Open Access Journals (Sweden)

    Erich Studerus

    Full Text Available Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24 predictor variables, including age, sex, education, personality traits, drug pre-experience, mental state before drug intake, experimental setting, and drug dose on the acute response to psilocybin. The analysis was based on the pooled data of 23 controlled experimental studies involving 409 psilocybin administrations to 261 healthy volunteers. Multiple linear mixed effects models were fitted for each of 15 response variables. Although drug dose was clearly the most important predictor for all measured response variables, several non-pharmacological variables significantly contributed to the effects of psilocybin. Specifically, having a high score in the personality trait of Absorption, being in an emotionally excitable and active state immediately before drug intake, and having experienced few psychological problems in past weeks were most strongly associated with pleasant and mystical-type experiences, whereas high Emotional Excitability, low age, and an experimental setting involving positron emission tomography most strongly predicted unpleasant and/or anxious reactions to psilocybin. The results confirm that non-pharmacological variables play an important role in the effects of psilocybin.

  13. Prediction of psilocybin response in healthy volunteers.

    Science.gov (United States)

    Studerus, Erich; Gamma, Alex; Kometer, Michael; Vollenweider, Franz X

    2012-01-01

    Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24 predictor variables, including age, sex, education, personality traits, drug pre-experience, mental state before drug intake, experimental setting, and drug dose on the acute response to psilocybin. The analysis was based on the pooled data of 23 controlled experimental studies involving 409 psilocybin administrations to 261 healthy volunteers. Multiple linear mixed effects models were fitted for each of 15 response variables. Although drug dose was clearly the most important predictor for all measured response variables, several non-pharmacological variables significantly contributed to the effects of psilocybin. Specifically, having a high score in the personality trait of Absorption, being in an emotionally excitable and active state immediately before drug intake, and having experienced few psychological problems in past weeks were most strongly associated with pleasant and mystical-type experiences, whereas high Emotional Excitability, low age, and an experimental setting involving positron emission tomography most strongly predicted unpleasant and/or anxious reactions to psilocybin. The results confirm that non-pharmacological variables play an important role in the effects of psilocybin.

  14. Predicting Flutter and Forced Response in Turbomachinery

    Science.gov (United States)

    VanZante, Dale E.; Adamczyk, John J.; Srivastava, Rakesh; Bakhle, Milind A.; Shabbir, Aamir; Chen, Jen-Ping; Janus, J. Mark; To, Wai-Ming; Barter, John

    2005-01-01

    TURBO-AE is a computer code that enables detailed, high-fidelity modeling of aeroelastic and unsteady aerodynamic characteristics for prediction of flutter, forced response, and blade-row interaction effects in turbomachinery. Flow regimes that can be modeled include subsonic, transonic, and supersonic, with attached and/or separated flow fields. The three-dimensional Reynolds-averaged Navier-Stokes equations are solved numerically to obtain extremely accurate descriptions of unsteady flow fields in multistage turbomachinery configurations. Blade vibration is simulated by use of a dynamic-grid-deformation technique to calculate the energy exchange for determining the aerodynamic damping of vibrations of blades. The aerodynamic damping can be used to assess the stability of a blade row. TURBO-AE also calculates the unsteady blade loading attributable to such external sources of excitation as incoming gusts and blade-row interactions. These blade loadings, along with aerodynamic damping, are used to calculate the forced responses of blades to predict their fatigue lives. Phase-lagged boundary conditions based on the direct-store method are used to calculate nonzero interblade phase-angle oscillations; this practice eliminates the need to model multiple blade passages, and, hence, enables large savings in computational resources.

  15. Mood Predicts Response to Placebo CPAP

    Directory of Open Access Journals (Sweden)

    Carl J. Stepnowsky

    2012-01-01

    Full Text Available Study Objectives. Continuous positive airway pressure (CPAP therapy is efficacious for treating obstructive sleep apnea (OSA, but recent studies with placebo CPAP (CPAP administered at subtherapeutic pressure have revealed nonspecific (or placebo responses to CPAP treatment. This study examined baseline psychological factors associated with beneficial effects from placebo CPAP treatment. Participants. Twenty-five participants were studied with polysomnography at baseline and after treatment with placebo CPAP. Design. Participants were randomized to either CPAP treatment or placebo CPAP. Baseline mood was assessed with the Profile of Mood States (POMS. Total mood disturbance (POMS-Total was obtained by summing the six POMS subscale scores, with Vigor weighted negatively. The dependent variable was changed in apnea-hypopnea index (ΔAHI, calculated by subtracting pre- from post-CPAP AHI. Negative values implied improvement. Hierarchical regression analysis was performed, with pre-CPAP AHI added as a covariate to control for baseline OSA severity. Results. Baseline emotional distress predicted the drop in AHI in response to placebo CPAP. Highly distressed patients showed greater placebo response, with a 34% drop (i.e., improvement in AHI. Conclusion. These findings underscore the importance of placebo-controlled studies of CPAP treatment. Whereas such trials are routinely included in drug trials, this paper argues for their importance even in mechanical-oriented sleep interventions.

  16. Predictability of Biogeochemical Responses in Engineered Watersheds

    Science.gov (United States)

    Yaeger, M. A.; Voepel, H. E.; Basu, N. B.; Rao, P. C.; Donner, S. D.; Packman, A. I.

    2009-12-01

    Examining the impacts of large-scale human modifications of watersheds (e.g., land-use intensification for food production; hydrologic modification through extensive tile-drainage, etc.) on the hydrologic and biogeochemical responses, and ecological impacts at various scales has been the focus of monitoring and modeling studies over the past two decades. Complex interactions between hydrology and biogeochemistry and the need to predict responses across scales has led to the development of detailed process-based models that are computationally intensive and calibration-dependent. Our overall hypothesis is that human modifications and intensive management of these watersheds have led to more predictable responses, which are typical of engineered, less-complex systems rather than natural, complex systems. We examined monitoring data for nitrogen, phosphorous, silica and chloride in 25 large watersheds (10,000 km2 to 500,000 km2) in the Mississippi River Basin. This sparse dataset was complemented with nitrogen cycling and hydrology output from a whole-basin terrestrial and aquatic modeling system (IBIS-THMB). These sub-basins have diverse land uses, although agriculture still dominates (from ~30% to ~80%). Despite diversity in soils, geology, rainfall patterns, and land use, a linear relationship was observed between the annual cumulative discharge (Q; m3/yr) and the measured nitrate load (L; kg/yr). The slopes of these linear L-Q plots represent the flow-weighted annual average concentrations (Cf), and a linear L-Q relationship indicates an apparent “chemostatic” response of these large watersheds. Analysis of Mississippi River monitoring data for nitrate and IBIS-THMB simulations revealed that Cf is a strong function of land-use (eg, percent corn) that defines the chemical input function. The scatter around the L-Q plots was small for “endogenous” (generated from internal sources) solutes (eg, silica), intermediate for “hybrid” (contributions from both

  17. Response Predicting LTCC Firing Shrinkage: A Response Surface Analysis Study

    Energy Technology Data Exchange (ETDEWEB)

    Girardi, Michael; Barner, Gregg; Lopez, Cristie; Duncan, Brent; Zawicki, Larry

    2009-02-25

    The Low Temperature Cofired Ceramic (LTCC) technology is used in a variety of applications including military/space electronics, wireless communication, MEMS, medical and automotive electronics. The use of LTCC is growing due to the low cost of investment, short development time, good electrical and mechanical properties, high reliability, and flexibility in design integration (3 dimensional (3D) microstructures with cavities are possible)). The dimensional accuracy of the resulting x/y shrinkage of LTCC substrates is responsible for component assembly problems with the tolerance effect that increases in relation to the substrate size. Response Surface Analysis was used to predict product shrinkage based on specific process inputs (metal loading, layer count, lamination pressure, and tape thickness) with the ultimate goal to optimize manufacturing outputs (NC files, stencils, and screens) in achieving the final product design the first time. Three (3) regression models were developed for the DuPont 951 tape system with DuPont 5734 gold metallization based on green tape thickness.

  18. Classification of frequency response areas in the inferior colliculus reveals continua not discrete classes

    OpenAIRE

    Palmer, Alan R; Shackleton, Trevor M.; Sumner, Christian J.; Zobay, Oliver; Rees, Adrian

    2013-01-01

    A differential response to sound frequency is a fundamental property of auditory neurons. Frequency analysis in the cochlea gives rise to V-shaped tuning functions in auditory nerve fibres, but by the level of the inferior colliculus (IC), the midbrain nucleus of the auditory pathway, neuronal receptive fields display diverse shapes that reflect the interplay of excitation and inhibition. The origin and nature of these frequency receptive field types is still open to question. One proposed hy...

  19. Identifying the Threshold of Iron Deficiency in the Central Nervous System of the Rat by the Auditory Brainstem Response

    OpenAIRE

    Greminger, Allison R.; Mayer-Pröschel, Margot

    2015-01-01

    The deleterious effects of anemia on auditory nerve (AN) development have been well investigated; however, we have previously reported that significant functional consequences in the auditory brainstem response (ABR) can also occur as a consequence of marginal iron deficiency (ID). As the ABR has widespread clinical use, we evaluated the ability of this electrophysiological method to characterize the threshold of tissue ID in rats by examining the relationship between markers of tissue ID and...

  20. Medial olivocochlear efferent inhibition of basilar-membrane responses to clicks: Evidence for two modes of cochlear mechanical excitation

    OpenAIRE

    Guinan, John J.; Cooper, Nigel P.

    2008-01-01

    Conceptualizations of mammalian cochlear mechanics are based on basilar-membrane (BM) traveling waves that scale with frequency along the length of the cochlea, are amplified by outer hair cells (OHCs), and excite inner hair cells and auditory-nerve (AN) fibers in a simple way. However, recent experimental work has shown medial-olivocochlear (MOC) inhibition of AN responses to clicks that do not fit with this picture. To test whether this AN-initial-peak (ANIP) inhibition might result from hi...

  1. 基于听觉神经同步振荡网络的时频结构描述方法%Novel Method for Time-frequency Structure Description Based on Synchronized Oscillatory Network of Auditory Nerve Fiber

    Institute of Scientific and Technical Information of China (English)

    李允公; 张金萍; 戴丽; 张占一

    2012-01-01

    人类听觉系统具有优良的非平稳信号分析能力,在听觉系统中,由耳蜗基底膜对信号进行类似于带通滤波的时频分解,并由内毛细胞、传入神经和听觉中枢的神经网络对时频分解结果逐步进行特征信息提取和压缩.鉴于此,参照Wang-Brown模型,建立一种可描述信号时频结构特征的听觉模型,该模型包括基底膜、内毛细胞、中级听觉和听觉中枢等子模型,听觉中枢模型由单层听神经振荡网络构成.略去Wang-Brown模型中随机项和侧抑制项,简化内毛细胞模型,设计听神经元的活跃准则和神经元间的联接方式.信号经基底膜、内毛细胞和中级听觉模型处理后,由听神经振荡网络进行信息综合,使得信号中时频结构相似的区域所对应的听神经元进行同步振荡,从而可利用同步振荡神经元的分布情况描述信号的时频结构.进行故障转子升降速试验和风力发电增速机稳速运行试验,试验所得信号的分析结果表明,所建模型能够有效描述信号的时频结构特征及其变化情况,对信号的瞬态变化较为敏感,且数据量相对较小,易于智能识别.%The human auditory system possesses excellent capability to analysis non-stationary signal. In auditory system, before a signal is recognized by the auditory cortex, it is sequentially processed by the basilar membrane, which can be seen as a bandpass filterbank, and other elements in auditory system. Therefore, to describe the structure features of signal in time-frequency space, an auditory model is proposed based on Wang-Brown model and the auditory nerve fiber oscillatory network with single layer. This model consists of basilar membrane, inner hair cells, middle auditory stage and auditory cortex, and the auditory cortex model is a single layer auditory nerve fiber oscillatory network. According to the characteristic of mechanical vibration signal, the random term and lateral inhibitor in Wang

  2. Extreme wave and wind response predictions

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Olsen, Anders S.; Mansour, Alaa E.

    2011-01-01

    The aim of the paper is to advocate effective stochastic procedures, based on the First Order Reliability Method (FORM) and Monte Carlo simulations (MCS), for extreme value predictions related to wave and wind-induced loads.Due to the efficient optimization procedures implemented in standard FORM...

  3. Slot Machine Response Frequency Predicts Pathological Gambling

    DEFF Research Database (Denmark)

    Linnet, Jakob; Rømer Thomsen, Kristine; Møller, Arne;

    2013-01-01

    Slot machines are among the most addictive forms of gambling, and pathological gambling slot machine players represent the largest group of treatment seekers, accounting for 35% to 93% of the population. Pathological gambling sufferers have significantly higher response frequency (games / time......) on slot machines compared with non-problem gamblers, which may suggest increased reinforcement of the gambling behavior in pathological gambling. However, to date it is unknown whether or not the increased response frequency in pathological gambling is associated with symptom severity of the disorder....... This study tested the hypothesis that response frequency is associated with symptom severity in pathological gambling. We tested response frequency among twenty-two pathological gambling sufferers and twenty-one non-problem gamblers on a commercially available slot machine, and screened for pathological...

  4. Resting state functional connectivity predicts neurofeedback response

    OpenAIRE

    Scheinost, Dustin; Stoica, Teodora; Wasylink, Suzanne; Gruner, Patricia; Saksa, John; Pittenger, Christopher; Hampson, Michelle

    2014-01-01

    Tailoring treatments to the specific needs and biology of individual patients—personalized medicine—requires delineation of reliable predictors of response. Unfortunately, these have been slow to emerge, especially in neuropsychiatric disorders. We have recently described a real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback protocol that can reduce contamination-related anxiety, a prominent symptom of many cases of obsessive-compulsive disorder (OCD). Individual response ...

  5. Prediction of nuclear hormone receptor response elements.

    Science.gov (United States)

    Sandelin, Albin; Wasserman, Wyeth W

    2005-03-01

    The nuclear receptor (NR) class of transcription factors controls critical regulatory events in key developmental processes, homeostasis maintenance, and medically important diseases and conditions. Identification of the members of a regulon controlled by a NR could provide an accelerated understanding of development and disease. New bioinformatics methods for the analysis of regulatory sequences are required to address the complex properties associated with known regulatory elements targeted by the receptors because the standard methods for binding site prediction fail to reflect the diverse target site configurations. We have constructed a flexible Hidden Markov Model framework capable of predicting NHR binding sites. The model allows for variable spacing and orientation of half-sites. In a genome-scale analysis enabled by the model, we show that NRs in Fugu rubripes have a significant cross-regulatory potential. The model is implemented in a web interface, freely available for academic researchers, available at http://mordor.cgb.ki.se/NHR-scan. PMID:15563547

  6. Mood Predicts Response to Placebo CPAP

    OpenAIRE

    Stepnowsky, Carl J.; Wei-Chung Mao; Bardwell, Wayne A; José S. Loredo; Joel E Dimsdale

    2012-01-01

    Study Objectives. Continuous positive airway pressure (CPAP) therapy is efficacious for treating obstructive sleep apnea (OSA), but recent studies with placebo CPAP (CPAP administered at subtherapeutic pressure) have revealed nonspecific (or placebo) responses to CPAP treatment. This study examined baseline psychological factors associated with beneficial effects from placebo CPAP treatment. Participants. Twenty-five participants were studied with polysomnography at baseline and after treatme...

  7. Mass Law Predicts Hyperbolic Hypoxic Ventilatory Response

    Science.gov (United States)

    Severinghaus, John W.

    The hyperbolic hypoxic ventilatory response vs PaO2, HVRp, is interpreted as relecting a mass hyperbolic relationship of cytochrome PcO2 to cytochrome potential Ec, offset 32 torr by the constant diffusion gradient between arterial blood and cytochrome in CB at its constant metabolic rate dot VO_2 . Ec is taken to be a linear function of redox reduction and CB ventilatory drive. As Ec rises in hypoxia, the absolute potentials of each step in the citric acid cycle rises equally while the potential drop across each step remains constant because flux rate remains constant. A hypothetic HVRs ( dot VE vs SaO2) response curve computed from these assumptions is strikingly non linear. A hypothetic HVRp calculated from an assumed linear HVRs cannot be fit to the observed hyperbolic increase of ventilation in response to isocapnic hypoxia at PO2 less than 40 torr. The incompatibility of these results suggest that in future studies HVRs will not be found to be linear, especially below 80% SaO2 and HVRp will fail to be accurately hyperbolic.

  8. Predicting Footbridge Response using Stochastic Load Models

    DEFF Research Database (Denmark)

    Pedersen, Lars; Frier, Christian

    2013-01-01

    Walking parameters such as step frequency, pedestrian mass, dynamic load factor, etc. are basically stochastic, although it is quite common to adapt deterministic models for these parameters. The present paper considers a stochastic approach to modeling the action of pedestrians, but when doing so...... decisions need to be made in terms of statistical distributions of walking parameters and in terms of the parameters describing the statistical distributions. The paper explores how sensitive computations of bridge response are to some of the decisions to be made in this respect. This is useful...

  9. Model for Predicting End User Web Page Response Time

    CERN Document Server

    Nagarajan, Sathya Narayanan

    2012-01-01

    Perceived responsiveness of a web page is one of the most important and least understood metrics of web page design, and is critical for attracting and maintaining a large audience. Web pages can be designed to meet performance SLAs early in the product lifecycle if there is a way to predict the apparent responsiveness of a particular page layout. Response time of a web page is largely influenced by page layout and various network characteristics. Since the network characteristics vary widely from country to country, accurately modeling and predicting the perceived responsiveness of a web page from the end user's perspective has traditionally proven very difficult. We propose a model for predicting end user web page response time based on web page, network, browser download and browser rendering characteristics. We start by understanding the key parameters that affect perceived response time. We then model each of these parameters individually using experimental tests and statistical techniques. Finally, we d...

  10. Dopamine neurons share common response function for reward prediction error.

    Science.gov (United States)

    Eshel, Neir; Tian, Ju; Bukwich, Michael; Uchida, Naoshige

    2016-03-01

    Dopamine neurons are thought to signal reward prediction error, or the difference between actual and predicted reward. How dopamine neurons jointly encode this information, however, remains unclear. One possibility is that different neurons specialize in different aspects of prediction error; another is that each neuron calculates prediction error in the same way. We recorded from optogenetically identified dopamine neurons in the lateral ventral tegmental area (VTA) while mice performed classical conditioning tasks. Our tasks allowed us to determine the full prediction error functions of dopamine neurons and compare them to each other. We found marked homogeneity among individual dopamine neurons: their responses to both unexpected and expected rewards followed the same function, just scaled up or down. As a result, we were able to describe both individual and population responses using just two parameters. Such uniformity ensures robust information coding, allowing each dopamine neuron to contribute fully to the prediction error signal.

  11. Model Predictive Control based on Finite Impulse Response Models

    DEFF Research Database (Denmark)

    Prasath, Guru; Jørgensen, John Bagterp

    2008-01-01

    We develop a regularized l2 finite impulse response (FIR) predictive controller with input and input-rate constraints. Feedback is based on a simple constant output disturbance filter. The performance of the predictive controller in the face of plant-model mismatch is investigated by simulations ...

  12. Brain Connectivity Predicts Placebo Response across Chronic Pain Clinical Trials

    Science.gov (United States)

    Tétreault, Pascal; Mansour, Ali; Vachon-Presseau, Etienne; Schnitzer, Thomas J.; Apkarian, A. Vania

    2016-01-01

    Placebo response in the clinical trial setting is poorly understood and alleged to be driven by statistical confounds, and its biological underpinnings are questioned. Here we identified and validated that clinical placebo response is predictable from resting-state functional magnetic-resonance-imaging (fMRI) brain connectivity. This also led to discovering a brain region predicting active drug response and demonstrating the adverse effect of active drug interfering with placebo analgesia. Chronic knee osteoarthritis (OA) pain patients (n = 56) underwent pretreatment brain scans in two clinical trials. Study 1 (n = 17) was a 2-wk single-blinded placebo pill trial. Study 2 (n = 39) was a 3-mo double-blinded randomized trial comparing placebo pill to duloxetine. Study 3, which was conducted in additional knee OA pain patients (n = 42), was observational. fMRI-derived brain connectivity maps in study 1 were contrasted between placebo responders and nonresponders and compared to healthy controls (n = 20). Study 2 validated the primary biomarker and identified a brain region predicting drug response. In both studies, approximately half of the participants exhibited analgesia with placebo treatment. In study 1, right midfrontal gyrus connectivity best identified placebo responders. In study 2, the same measure identified placebo responders (95% correct) and predicted the magnitude of placebo’s effectiveness. By subtracting away linearly modeled placebo analgesia from duloxetine response, we uncovered in 6/19 participants a tendency of duloxetine enhancing predicted placebo response, while in another 6/19, we uncovered a tendency for duloxetine to diminish it. Moreover, the approach led to discovering that right parahippocampus gyrus connectivity predicts drug analgesia after correcting for modeled placebo-related analgesia. Our evidence is consistent with clinical placebo response having biological underpinnings and shows that the method can also reveal that active

  13. Predicting unprotected reactor upset response using the maximum likelihood method

    International Nuclear Information System (INIS)

    A number of advanced reactor concepts incorporate intrinsic design features that act to safely limit reactor response during upsets. In the integral fast reactor (IFR) concept, for example, metallic fuel is used to provide sufficient negative reactivity feedback to achieve a safe response for a number of unprotected upsets. In reactors such as the IFR that rely on passive features for part of their safety, the licensing of these systems will probably require that they be periodically tested to verify proper operation. Commercial light water plants have similar requirements for active safety systems. The approach to testing considered in this paper involves determining during normal operation the values of key reactor parameters that govern the unprotected reactor response and then using these values to predict upset response. The values are determined using the maximum likelihood method. If the predicted reactor response is within safe limits, then one concludes that the intrinsic safety features are operating correctly

  14. Predicting Performance Under Stressful Conditions Using Galvanic Skin Response

    OpenAIRE

    Mundell, Carter; Vielma, Juan Pablo; Zaman, Tauhid

    2016-01-01

    The rapid growth of the availability of wearable biosensors has created the opportunity for using biological signals to measure worker performance. An important question is how to use such signals to not just measure, but actually predict worker performance on a task under stressful and potentially high risk conditions. Here we show that the biological signal known as galvanic skin response (GSR) allows such a prediction. We conduct an experiment where subjects answer arithmetic questions und...

  15. Fluid responsiveness is predicted by analysis of extra systoles

    DEFF Research Database (Denmark)

    Vistisen, Simon Tilma

    surrounding sinus beats and that the magnitude of the SBP change (DSBP) could predict fluid responsiveness. OBJECTIVES. To study the hypothesis in post-cardiac surgery patients. METHODS. Patients scheduled for a 500 ml volume expansion were observed. In the time frame, 0-30 min prior to volume expansion, ECG...... predict fluid responsiveness in post-cardiac surgery patients. The method needs to be validated in other patient groups. REFERENCE. [1] Mahjoub Y, et al., Evaluation of pulse pressure variation validity criteria in critically ill patients: a prospective observational multicentre point-prevalence study. Br...

  16. Outcome Prediction in Mathematical Models of Immune Response to Infection.

    Directory of Open Access Journals (Sweden)

    Manuel Mai

    Full Text Available Clinicians need to predict patient outcomes with high accuracy as early as possible after disease inception. In this manuscript, we show that patient-to-patient variability sets a fundamental limit on outcome prediction accuracy for a general class of mathematical models for the immune response to infection. However, accuracy can be increased at the expense of delayed prognosis. We investigate several systems of ordinary differential equations (ODEs that model the host immune response to a pathogen load. Advantages of systems of ODEs for investigating the immune response to infection include the ability to collect data on large numbers of 'virtual patients', each with a given set of model parameters, and obtain many time points during the course of the infection. We implement patient-to-patient variability v in the ODE models by randomly selecting the model parameters from distributions with coefficients of variation v that are centered on physiological values. We use logistic regression with one-versus-all classification to predict the discrete steady-state outcomes of the system. We find that the prediction algorithm achieves near 100% accuracy for v = 0, and the accuracy decreases with increasing v for all ODE models studied. The fact that multiple steady-state outcomes can be obtained for a given initial condition, i.e. the basins of attraction overlap in the space of initial conditions, limits the prediction accuracy for v > 0. Increasing the elapsed time of the variables used to train and test the classifier, increases the prediction accuracy, while adding explicit external noise to the ODE models decreases the prediction accuracy. Our results quantify the competition between early prognosis and high prediction accuracy that is frequently encountered by clinicians.

  17. PREDICTION OF FIGHT OR FLIGHT RESPONSE USING ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Abhijit Suresh

    2014-01-01

    Full Text Available The modern society has posed several threats to the public. Public security is declining with increasing anti-social behaviour. Cases of rape and terrorist attacks have become increasingly common and there is a strong demand for a security system to control such modalities. Anti-social behaviour is a key issue of public concern. Public perceptions, however, have been improving recently. The vital response to physical and emotional danger is called fight or flight response. It is a basic survival mechanism occurring in response to a specific stimulus, such as pain or the threat of danger. Predicting the flight and fight response is an important aspect to identify possible areas susceptible to such events and provide emergency assistance to the victims involved. This study analyses various physiological changes associated with fight or flight response and proposes an approach to predict measures that determines whether an individual is under fear caused due the perceived threat. The proposed approach uses feed forward neural networks with back propagation algorithm. With the physiological changes such as blood pressure, heart rate and respiratory rate as inputs, the optimal configuration of neural network was configured and the proposed system is able to predict the measure of fight or flight response with minimal error. By monitoring and identifying the fear measure it is possible to prevent or reduce the damage to the society by activities such as rape and terrorist attacks.

  18. Predicting aquifer response time for application in catchment modeling.

    Science.gov (United States)

    Walker, Glen R; Gilfedder, Mat; Dawes, Warrick R; Rassam, David W

    2015-01-01

    It is well established that changes in catchment land use can lead to significant impacts on water resources. Where land-use changes increase evapotranspiration there is a resultant decrease in groundwater recharge, which in turn decreases groundwater discharge to streams. The response time of changes in groundwater discharge to a change in recharge is a key aspect of predicting impacts of land-use change on catchment water yield. Predicting these impacts across the large catchments relevant to water resource planning can require the estimation of groundwater response times from hundreds of aquifers. At this scale, detailed site-specific measured data are often absent, and available spatial data are limited. While numerical models can be applied, there is little advantage if there are no detailed data to parameterize them. Simple analytical methods are useful in this situation, as they allow the variability in groundwater response to be incorporated into catchment hydrological models, with minimal modeling overhead. This paper describes an analytical model which has been developed to capture some of the features of real, sloping aquifer systems. The derived groundwater response timescale can be used to parameterize a groundwater discharge function, allowing groundwater response to be predicted in relation to different broad catchment characteristics at a level of complexity which matches the available data. The results from the analytical model are compared to published field data and numerical model results, and provide an approach with broad application to inform water resource planning in other large, data-scarce catchments. PMID:24842053

  19. The Pupillary Orienting Response Predicts Adaptive Behavioral Adjustment after Errors.

    Directory of Open Access Journals (Sweden)

    Peter R Murphy

    Full Text Available Reaction time (RT is commonly observed to slow down after an error. This post-error slowing (PES has been thought to arise from the strategic adoption of a more cautious response mode following deployment of cognitive control. Recently, an alternative account has suggested that PES results from interference due to an error-evoked orienting response. We investigated whether error-related orienting may in fact be a pre-cursor to adaptive post-error behavioral adjustment when the orienting response resolves before subsequent trial onset. We measured pupil dilation, a prototypical measure of autonomic orienting, during performance of a choice RT task with long inter-stimulus intervals, and found that the trial-by-trial magnitude of the error-evoked pupil response positively predicted both PES magnitude and the likelihood that the following response would be correct. These combined findings suggest that the magnitude of the error-related orienting response predicts an adaptive change of response strategy following errors, and thereby promote a reconciliation of the orienting and adaptive control accounts of PES.

  20. Simplified Analysis Model for Predicting Pyroshock Responses on Composite Panel

    Science.gov (United States)

    Iwasa, Takashi; Shi, Qinzhong

    A simplified analysis model based on the frequency response analysis and the wave propagation analysis was established for predicting Shock Response Spectrum (SRS) on the composite panel subjected to pyroshock loadings. The complex composite panel was modeled as an isotropic single layer panel defined in NASA Lewis Method. Through the conductance of an impact excitation test on a composite panel with no equipment mounted on, it was presented that the simplified analysis model could estimate the SRS as well as the acceleration peak values in both near and far field in an accurate way. In addition, through the simulation for actual pyroshock tests on an actual satellite system, the simplified analysis model was proved to be applicable in predicting the actual pyroshock responses, while bringing forth several technical issues to estimate the pyroshock test specifications in early design stages.

  1. Apoptosis and other immune biomarkers predict influenza vaccine responsiveness.

    Science.gov (United States)

    Furman, David; Jojic, Vladimir; Kidd, Brian; Shen-Orr, Shai; Price, Jordan; Jarrell, Justin; Tse, Tiffany; Huang, Huang; Lund, Peder; Maecker, Holden T; Utz, Paul J; Dekker, Cornelia L; Koller, Daphne; Davis, Mark M

    2013-01-01

    Despite the importance of the immune system in many diseases, there are currently no objective benchmarks of immunological health. In an effort to identifying such markers, we used influenza vaccination in 30 young (20-30 years) and 59 older subjects (60 to >89 years) as models for strong and weak immune responses, respectively, and assayed their serological responses to influenza strains as well as a wide variety of other parameters, including gene expression, antibodies to hemagglutinin peptides, serum cytokines, cell subset phenotypes and in vitro cytokine stimulation. Using machine learning, we identified nine variables that predict the antibody response with 84% accuracy. Two of these variables are involved in apoptosis, which positively associated with the response to vaccination and was confirmed to be a contributor to vaccine responsiveness in mice. The identification of these biomarkers provides new insights into what immune features may be most important for immune health. PMID:23591775

  2. Subjective responses to alcohol in the lab predict neural responses to alcohol cues

    OpenAIRE

    Courtney, KE; Ray, LA

    2014-01-01

    Objective: Subjective responses to alcohol represent a biologically based, genetically moderated, and clinically informative marker of alcoholism risk; however, the physiology underlying this phenotype remains unclear. This study tested whether subjective responses during alcohol administration predict neural responses to alcohol cues in the scanner and whether these neural responses differ between OPRM1 genotypes. Method: Twenty alcohol-dependent individuals were recruited (10 G-allele carri...

  3. Predictive functional control of integrating process based on impulse response

    Institute of Scientific and Technical Information of China (English)

    Bin ZHANG; Ping LI; Weidong ZHANG

    2004-01-01

    The predictive model is built according to the characteristics of the impulse response of integrating process. In order to eliminate the permanent offset between the setpoint and the process output in the presence of the load disturbance, a novel error compensation method is proposed. Then predictive functional control of integrating process is designed. The method given generates a simple control structure, which can significantly reduce online computation. Furthermore, the tuning of the controller is fairly straightforward. Simulation results indicate that the designed control system is relatively robust to the parameters variation of the process.

  4. Predicting the shock compression response of heterogeneous powder mixtures

    Science.gov (United States)

    Fredenburg, D. A.; Thadhani, N. N.

    2013-06-01

    A model framework for predicting the dynamic shock-compression response of heterogeneous powder mixtures using readily obtained measurements from quasi-static tests is presented. Low-strain-rate compression data are first analyzed to determine the region of the bulk response over which particle rearrangement does not contribute to compaction. This region is then fit to determine the densification modulus of the mixture, σD, an newly defined parameter describing the resistance of the mixture to yielding. The measured densification modulus, reflective of the diverse yielding phenomena that occur at the meso-scale, is implemented into a rate-independent formulation of the P-α model, which is combined with an isobaric equation of state to predict the low and high stress dynamic compression response of heterogeneous powder mixtures. The framework is applied to two metal + metal-oxide (thermite) powder mixtures, and good agreement between the model and experiment is obtained for all mixtures at stresses near and above those required to reach full density. At lower stresses, rate-dependencies of the constituents, and specifically those of the matrix constituent, determine the ability of the model to predict the measured response in the incomplete compaction regime.

  5. Mothers' labeling responses to infants' gestures predict vocabulary outcomes.

    Science.gov (United States)

    Olson, Janet; Masur, Elise Frank

    2015-11-01

    Twenty-nine infants aged 1;1 and their mothers were videotaped while interacting with toys for 18 minutes. Six experimental stimuli were presented to elicit infant communicative bids in two communicative intent contexts - proto-declarative and proto-imperative. Mothers' verbal responses to infants' gestural and non-gestural communicative bids were coded for object and action labels. Relations between maternal labeling responses and infants' vocabularies at 1;1 and 1;5 were examined. Mothers' labeling responses to infants' gestural communicative bids were concurrently and predictively related to infants' vocabularies, whereas responses to non-gestural communicative bids were not. Mothers' object labeling following gestures in the proto-declarative context mediated the association from infants' gesturing in the proto-declarative context to concurrent noun lexicons and was the strongest predictor of subsequent noun lexicons. Mothers' action labeling after infants' gestural bids in the proto-imperative context predicted infants' acquisition of action words at 1;5. Findings show that mothers' responsive labeling explain specific relations between infants' gestures and their vocabulary development. PMID:25643656

  6. Predictions of F-111 TACT aircraft buffet response

    Science.gov (United States)

    Cunningham, Atlee M., Jr.; Coe, Charles F.

    1990-01-01

    A summary is presented for the prediction method development and correlations of predicted response with flight test measurements. The prediction method was based on refinements to the method described by Cunningham. One improvement made use of direct time integration of the correlated fluctuating pressure data to obtain buffet excitation for the various modes of interest. Another improvement incorporated a hybrid technique for scaling measured wind tunnel damping data to full-scale for the modes of interest. A third improvement made use of the diagonalized form of the fully coupled equations of motion. Finally, a mechanism was described for explaining an apparent coupling between the aircraft wing torsion modes and shock induced trailing edge separation that led to very high wing motion on the aircraft that was not observed on the wind tunnel model.

  7. Synchrony suppression in complex stimulus responses of a biophysical model of the cochlea.

    Science.gov (United States)

    Shamma, S A; Morrish, K A

    1987-05-01

    A minimal biophysical model of the cochlea is used to investigate the validity of the hypothesis that a single compressive nonlinearity at the hair cell level can explain some of the suppression phenomena in cochlear responses to complex stimuli. The dependencies of the model responses on the amplitudes and frequencies of two-tone stimuli resemble in many respects the behavior of the experimental data, and can be traced to explicit biophysical parameters in the model. Most discrepancies between theory and experiment stem from simplifications in parameters of the minimal model that play no direct role in the hypothesis. The analysis and simulations predict further results which, pending experimental verification, may provide a more direct test of the influence of the compressive nonlinearity on the relative amplitudes of the synchronous response components, and hence of its role in synchrony suppression. For instance, regardless of the overall absolute levels of a two-tone stimulus applied to this type of model, the ratio of the amplitudes at the input and the ratio of the corresponding responses at the output remain approximately constant and equal (the output ratio changes by at most 6 dB in favor of the stronger tone). Other nonlinear responses to multitonal stimuli can also be reproduced, such as "spectral edge enhancement" [Horst et al., Peripheral Auditory Mechanisms (Springer, Berlin, 1985)] and some aspects of three-tone suppression [Javel et al., Mechanisms of Hearing (Monash U.P., Australia, 1983)]. In contrast to the complex behavior of suppression with increasing sound intensity and the drastic influence of the compressive nonlinearity on the absolute response measures on the auditory nerve (e.g., average rate and synchrony profiles), the percepts of complex sounds are relatively stable. This suggests that the invariant relative response measures are more likely used in the encoding and CNS extraction of the spectrum of complex stimuli such as speech.

  8. Plasma Biomarkers Can Predict Treatment Response in Tuberculosis Patients

    OpenAIRE

    Lee, Meng-Rui; Tsai, Chia-Jung; Wang, Wei-Jie; Chuang, Tzu-Yi; Yang, Chih-Mann; Chang, Lih-Yu; Lin, Ching-Kai; Wang, Jann-Yuan; Shu, Chin-Chong; Lee, Li-Na; Yu, Chong-Jen

    2015-01-01

    Abstract Despite numerous studies, there has been little progress in the use of biomarkers for predicting treatment response in patients with tuberculosis (TB). Patients with culture-confirmed pulmonary TB between 2010 and 2014 were prospectively recruited. Blood samples were taken upon diagnosis and 2 months after the start of standard anti-TB treatment. A pilot study utilizing measurement of TB-antigen-stimulated cytokines was conducted to select potential biomarkers for further testing. Ou...

  9. Predictive factors associated with hepatitis C antiviraltherapy response

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Hepatitis C virus (HCV) infection may lead to significantliver injury, and viral, environmental, host, immunologicand genetic factors may contribute to the differencesin the disease expression and treatment response.In the early 2000s, dual therapy using a combination of pegylated interferon plus ribavirin (PR) becamethe standard of care for HCV treatment. In this PRera, predictive factors of therapy response related tovirus and host have been identified. In 2010/2011,therapeutic regimens for HCV genotype 1 patients weremodified, and the addition of NS3/4a protease inhibitors(boceprevir or telaprevir) to dual therapy increasedthe effectiveness and chances of sustained virologicresponse (SVR). Nevertheless, the first-generation tripletherapy is associated with many adverse events, some ofwhich are serious and associated with death, particularlyin cirrhotic patients. This led to the need to identifyviral and host predictive factors that might influencethe SVR rate to triple therapy and avoid unnecessaryexposure to these drugs. Over the past four years,hepatitis C treatment has been rapidly changing with thedevelopment of new therapies and other developments.Currently, with the more recent generations of pangenotipicantiviral therapies, there have been highersustained virologic rates, and prognostic factors maynot have the same importance and strength as before.Nonetheless, some variables may still be consistent withthe low rates of non-response with regimens that includesofosbuvir, daclatasvir and ledipasvir. In this manuscript,we review the predictive factors of therapy responseacross the different treatment regimens over the lastdecade including the new antiviral drugs.

  10. Predicting the response of olfactory sensory neurons to odor mixtures from single odor response

    Science.gov (United States)

    Marasco, Addolorata; de Paris, Alessandro; Migliore, Michele

    2016-04-01

    The response of olfactory receptor neurons to odor mixtures is not well understood. Here, using experimental constraints, we investigate the mathematical structure of the odor response space and its consequences. The analysis suggests that the odor response space is 3-dimensional, and predicts that the dose-response curve of an odor receptor can be obtained, in most cases, from three primary components with specific properties. This opens the way to an objective procedure to obtain specific olfactory receptor responses by manipulating mixtures in a mathematically predictable manner. This result is general and applies, independently of the number of odor components, to any olfactory sensory neuron type with a response curve that can be represented as a sigmoidal function of the odor concentration.

  11. Elevated EBNA1 Immune Responses Predict Conversion to Multiple Sclerosis

    Science.gov (United States)

    Lünemann, Jan D.; Tintoré, Mar; Messmer, Brady; Strowig, Till; Rovira, Álex; Perkal, Héctor; Caballero, Estrella; Münz, Christian; Montalban, Xavier; Comabella, Manuel

    2009-01-01

    Objective The aims of the study were to determine the immune responses to candidate viral triggers of multiple sclerosis (MS) in patients with clinically isolated syndromes (CIS), and to evaluate their potential value in predicting conversion to MS. Methods Immune responses to Epstein-Barr virus (EBV), human herpesvirus 6, cytomegalovirus (HCMV), and measles were determined in a cohort of 147 CIS patients with a mean follow-up of 7 years and compared with 50 demographically matched controls. Results Compared to controls, CIS patients showed increased humoral (p<0.0001) and cellular (p=0.007) immune responses to the EBV-encoded nuclear antigen-1 (EBNA1), but not to other EBV-derived proteins. IgG responses to other virus antigens and frequencies of T cells specific for HCMV and influenza virus gene products were unchanged in CIS patients. EBNA1 was the only viral antigen towards which immune responses correlated with number of T2 lesions (p=0.006) and number of Barkhof criteria (p=0.001) at baseline, and with number of T2 lesions (p=0.012 both at 1 and 5 years), presence of new T2 lesions (p=0.003 and p=0.028 at 1 and 5 years), and EDSS (p=0.015 and p=0.010 at 1 and 5 years) during follow-up. In a univariate Cox regression model, increased EBNA1-specific IgG responses predicted conversion to MS based on McDonald criteria [hazard ratio (95% confidence interval), 2.2 (1.2–4.3); p=0.003]. Interpretation Our results indicate that elevated immune responses towards EBNA1 are selectively increased in CIS patients and suggest that EBNA1-specific IgG titers could be used as a prognostic marker for disease conversion and disability progression. PMID:20225269

  12. Serum metabolites predict response to angiotensin II receptor blockers in patients with diabetes mellitus

    NARCIS (Netherlands)

    Pena, Michelle J; Heinzel, Andreas; Rossing, Peter; Parving, Hans-Henrik; Dallmann, Guido; Rossing, Kasper; Andersen, Steen; Mayer, Bernd; Heerspink, Hiddo J L

    2016-01-01

    BACKGROUND: Individual patients show a large variability in albuminuria response to angiotensin receptor blockers (ARB). Identifying novel biomarkers that predict ARB response may help tailor therapy. We aimed to discover and validate a serum metabolite classifier that predicts albuminuria response

  13. Serum metabolites predict response to angiotensin II receptor blockers in patients with diabetes mellitus

    NARCIS (Netherlands)

    Pena, Michelle J.; Heinzel, Andreas; Rossing, Peter; Parving, Hans-Henrik; Dallmann, Guido; Rossing, Kasper; Andersen, Steen; Mayer, Bernd; Heerspink, Hiddo J. L.

    2016-01-01

    Background: Individual patients show a large variability in albuminuria response to angiotensin receptor blockers (ARB). Identifying novel biomarkers that predict ARB response may help tailor therapy. We aimed to discover and validate a serum metabolite classifier that predicts albuminuria response

  14. Coping styles predict responsiveness to cognitive behaviour therapy in psychosis.

    Science.gov (United States)

    Premkumar, Preethi; Peters, Emmanuelle R; Fannon, Dominic; Anilkumar, Anantha P; Kuipers, Elizabeth; Kumari, Veena

    2011-05-30

    The study aimed to determine the clinical and neuropsychological predictors of responsiveness to cognitive behavioural therapy for psychosis (CBTp). Sixty patients with schizophrenia or schizoaffective disorder and 25 healthy individuals took part in the study. Thirty patients (25 protocol completers) received CBTp in addition to standard care (SC); 30 patients (18 protocol completers) received SC only. All patients were assessed on symptoms using the Positive and Negative Syndrome Scale (PANSS) and clinical and neuropsychological function before and after CBTp. Symptoms and self-esteem improved to a greater extent in the CBTp+SC than SC control group. Greater pre-therapy coping ability and the self-reflectiveness dimension of cognitive insight at baseline predicted improvement in symptoms in the CBTp+SC group, but not the SC control group, explaining up to 21% of the variance in symptom improvement. Pre-therapy neuropsychological function, duration of illness, clinical insight and gender did not predict CBTp responsiveness. Being able to have a range of coping strategies and reflect on one's experiences while refraining from overconfidence in one's interpretations before therapy is conducive to better CBTp responsiveness. PMID:21262541

  15. MGMT expression predicts response to temozolomide in pancreatic neuroendocrine tumors.

    Science.gov (United States)

    Cros, J; Hentic, O; Rebours, V; Zappa, M; Gille, N; Theou-Anton, N; Vernerey, D; Maire, F; Lévy, P; Bedossa, P; Paradis, V; Hammel, P; Ruszniewski, P; Couvelard, A

    2016-08-01

    Temozolomide (TEM) showed encouraging results in well-differentiated pancreatic neuroendocrine tumors (WDPNETs). Low O(6)-methylguanine-DNA methyltransferase (MGMT) expression and MGMT promoter methylation within tumors correlate with a better outcome under TEM-based chemotherapy in glioblastoma. We aimed to assess whether MGMT expression and MGMT promoter methylation could help predict the efficacy of TEM-based chemotherapy in patients with WDPNET. Consecutive patients with progressive WDPNET and/or liver involvement over 50% who received TEM between 2006 and 2012 were retrospectively studied. Tumor response was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 guidelines. Nuclear expression of MGMT was assessed by immunochemistry (H-score, 0-300) and MGMT promoter methylation by pyrosequencing. Forty-three patients (21 men, 58years (27-84)) with grade 1 WDPNET (n=6) or 2 (n=36) were analyzed. Objective response, stable disease, and progression rates were seen in 17 patients (39.5%), 18 patients (41.9%), and 8 patients (18.6%), respectively. Low MGMT expression (≤50) was associated with radiological objective response (P=0.04) and better progression-free survival (PFS) (HR=0.35 (0.15-0.81), P=0.01). Disease control rate at 18months of treatment remained satisfying with an MGMT score up to 100 (74%) but dropped with a higher expression. High MGMT promoter methylation was associated with a low MGMT expression and longer PFS (HR=0.37 (0.29-1.08), P=0.05). Low MGMT score (≤50) appears to predict an objective tumor response, whereas an intermediate MGMT score (50-100) seems to be associated with prolonged stable disease.

  16. Uncontrolled diabetes predicts poor response to novel antiandrogens.

    Science.gov (United States)

    Karantanos, Theodoros; Karanika, Styliani; Gignac, Gretchen

    2016-09-01

    Metabolic abnormalities including hyperglycemia and hyperlipidemia have been associated with worse prognosis of prostate cancer (PCa), but there are limited data regarding their impact on the prognosis of castrate-resistant prostate cancer (CRPC) and the response of novel antiandrogens, namely abiraterone acetate (AA) and enzalutamide. Retrospective analysis of 61 patients with CRPC on AA or enzalutamide, treated at the Boston Medical Center, was performed. We evaluated hemoglobin A1c (HbA1c), HDL, LDL, Triglycerides and BMI within 2months before the initiation of treatment with AA or enzalutamide and progression-free survival (PFS) under this treatment. Regression analysis and analysis of variance were used to evaluate the data. HbA1c levels were found to predict adversely the PFS on the novel agents (df (1, 37), P=0.00, R(2)=0.40, coeff=-3.28). The Kaplan-Meier analysis showed that there is significant difference in survival between the HbA1c 4.7-5.9% compared with patients with HbA1c 7.8-11.6% (6.72±1.3months, log rank test P<0.0001) LDL (P=0.07), HDL (P=0.14), and triglycerides (P=0.33) were not found to predict PFS. BMI predicted PFS positively (df (1.59), P=0.02, R(2)=0.09, coeff=0.03), but not independently of HbA1c (P=0.07). No significant implications of social and family history, previous chemotherapy regimen, and Gleason score with PFS were found. Multiple markers of patients' health state were not associated with HbA1c values. Uncontrolled diabetes can predict for poor response of CRPC patients to AA and enzalutamide determining PFS under this treatment. Elevated BMI can positively affect PFS at this stage of disease. PMID:27515296

  17. Human arm posture prediction in response to isometric endpoint forces.

    Science.gov (United States)

    Davoudabadi Farahani, Saeed; Andersen, Michael Skipper; de Zee, Mark; Rasmussen, John

    2015-11-26

    The ability to predict the musculoskeletal response to external loads has multiple applications for the design of machines with a human interface and for the prediction of outcomes of musculoskeletal interventions. In this study, we applied an inverse-inverse dynamics technique to investigate its ability to predict arm posture in response to isometric hand forces. For each subject, we made a three-dimensional musculoskeletal model using the AnyBody Modelling System (AMS). Then, we had each subject-specific model hold a weight anteriorly to the right shoulder joint at a distance of half of the arm length. We selected the glenohumeral abduction angle (GHAA) as the only free parameter. Subsequently, we used inverse-inverse dynamics to find the optimal GHAA that minimised a performance criterion with physiological constraints. In this study, we investigated the performance of two different objective functions: summation of squared muscle activity (SSMA) and summation of squared normalised joint torques (SSNJT). To validate the simulation results, arm posture responses to different isometric downward hand forces were measured for six healthy male subjects. Five trials were performed for each loading condition. The results showed that, with an increase in hand load, there was a reduced GHAA in all subjects. Another interesting finding was that self-selected postures for lighter tasks varied more than postures for heavier tasks for all subjects. To understand this, we investigated the curvature of the objective function as a function of the load and observed an increased curvature with increased load. This may explain the reduced intra-subject variations observed for increasing loads.

  18. Human arm posture prediction in response to isometric endpoint forces.

    Science.gov (United States)

    Davoudabadi Farahani, Saeed; Andersen, Michael Skipper; de Zee, Mark; Rasmussen, John

    2015-11-26

    The ability to predict the musculoskeletal response to external loads has multiple applications for the design of machines with a human interface and for the prediction of outcomes of musculoskeletal interventions. In this study, we applied an inverse-inverse dynamics technique to investigate its ability to predict arm posture in response to isometric hand forces. For each subject, we made a three-dimensional musculoskeletal model using the AnyBody Modelling System (AMS). Then, we had each subject-specific model hold a weight anteriorly to the right shoulder joint at a distance of half of the arm length. We selected the glenohumeral abduction angle (GHAA) as the only free parameter. Subsequently, we used inverse-inverse dynamics to find the optimal GHAA that minimised a performance criterion with physiological constraints. In this study, we investigated the performance of two different objective functions: summation of squared muscle activity (SSMA) and summation of squared normalised joint torques (SSNJT). To validate the simulation results, arm posture responses to different isometric downward hand forces were measured for six healthy male subjects. Five trials were performed for each loading condition. The results showed that, with an increase in hand load, there was a reduced GHAA in all subjects. Another interesting finding was that self-selected postures for lighter tasks varied more than postures for heavier tasks for all subjects. To understand this, we investigated the curvature of the objective function as a function of the load and observed an increased curvature with increased load. This may explain the reduced intra-subject variations observed for increasing loads. PMID:26482735

  19. Predicting Ecosystem Response to Perturbation from Thermodynamic Criteria

    CERN Document Server

    Michaelian, K

    2008-01-01

    The response of ecosystems to perturbations is considered from a thermodynamic perspective by acknowledging that, as for all macroscopic systems and processes, the dynamics and stability of ecosystems is subject to definite thermodynamic law. For open ecosystems, exchanging energy, work, and mass with the environment, the thermodynamic criteria come from non-equilibrium or irreversible thermodynamics. For ecosystems during periods in which the boundary conditions may be considered as being constant, it is shown that criteria from irreversible thermodynamic theory are sufficient to permit a quantitative prediction of ecosystem response to perturbation. This framework is shown to provide a new perspective on the population dynamics of real ecosystems. The formalism is applied to the problem of the population oscillations of the southern pine beetle.

  20. Footbridge Response Predictions and Their Sensitivity to Stochastic Load Assumptions

    DEFF Research Database (Denmark)

    Pedersen, Lars; Frier, Christian

    2011-01-01

    Knowledge about footbridges response to actions of walking is important in assessments of vibration serviceability. In a number of design codes for footbridges, the vibration serviceability limit state is assessed using a walking load model in which the walking parameters (step frequency......, pedestrian mass, dynamic load factor, etc.) are modelled deterministically. This is a simplification of matters, as the walking parameters are basically stochastic as they will be different from one pedestrian to the next. The present paper considers a stochastic approach to modelling the action...... of pedestrians for predicting footbridge response, which is meaningful, and a step forward. Modelling walking parameters stochastically, however, requires decisions to be made in terms of their statistical distribution and the parameters describing the statistical distribution. The paper investigates...

  1. Global genetic variations predict brain response to faces.

    Science.gov (United States)

    Dickie, Erin W; Tahmasebi, Amir; French, Leon; Kovacevic, Natasa; Banaschewski, Tobias; Barker, Gareth J; Bokde, Arun; Büchel, Christian; Conrod, Patricia; Flor, Herta; Garavan, Hugh; Gallinat, Juergen; Gowland, Penny; Heinz, Andreas; Ittermann, Bernd; Lawrence, Claire; Mann, Karl; Martinot, Jean-Luc; Nees, Frauke; Nichols, Thomas; Lathrop, Mark; Loth, Eva; Pausova, Zdenka; Rietschel, Marcela; Smolka, Michal N; Ströhle, Andreas; Toro, Roberto; Schumann, Gunter; Paus, Tomáš

    2014-08-01

    Face expressions are a rich source of social signals. Here we estimated the proportion of phenotypic variance in the brain response to facial expressions explained by common genetic variance captured by ∼ 500,000 single nucleotide polymorphisms. Using genomic-relationship-matrix restricted maximum likelihood (GREML), we related this global genetic variance to that in the brain response to facial expressions, as assessed with functional magnetic resonance imaging (fMRI) in a community-based sample of adolescents (n = 1,620). Brain response to facial expressions was measured in 25 regions constituting a face network, as defined previously. In 9 out of these 25 regions, common genetic variance explained a significant proportion of phenotypic variance (40-50%) in their response to ambiguous facial expressions; this was not the case for angry facial expressions. Across the network, the strength of the genotype-phenotype relationship varied as a function of the inter-individual variability in the number of functional connections possessed by a given region (R(2) = 0.38, p<0.001). Furthermore, this variability showed an inverted U relationship with both the number of observed connections (R2 = 0.48, p<0.001) and the magnitude of brain response (R(2) = 0.32, p<0.001). Thus, a significant proportion of the brain response to facial expressions is predicted by common genetic variance in a subset of regions constituting the face network. These regions show the highest inter-individual variability in the number of connections with other network nodes, suggesting that the genetic model captures variations across the adolescent brains in co-opting these regions into the face network.

  2. Global genetic variations predict brain response to faces.

    Directory of Open Access Journals (Sweden)

    Erin W Dickie

    2014-08-01

    Full Text Available Face expressions are a rich source of social signals. Here we estimated the proportion of phenotypic variance in the brain response to facial expressions explained by common genetic variance captured by ∼ 500,000 single nucleotide polymorphisms. Using genomic-relationship-matrix restricted maximum likelihood (GREML, we related this global genetic variance to that in the brain response to facial expressions, as assessed with functional magnetic resonance imaging (fMRI in a community-based sample of adolescents (n = 1,620. Brain response to facial expressions was measured in 25 regions constituting a face network, as defined previously. In 9 out of these 25 regions, common genetic variance explained a significant proportion of phenotypic variance (40-50% in their response to ambiguous facial expressions; this was not the case for angry facial expressions. Across the network, the strength of the genotype-phenotype relationship varied as a function of the inter-individual variability in the number of functional connections possessed by a given region (R(2 = 0.38, p<0.001. Furthermore, this variability showed an inverted U relationship with both the number of observed connections (R2 = 0.48, p<0.001 and the magnitude of brain response (R(2 = 0.32, p<0.001. Thus, a significant proportion of the brain response to facial expressions is predicted by common genetic variance in a subset of regions constituting the face network. These regions show the highest inter-individual variability in the number of connections with other network nodes, suggesting that the genetic model captures variations across the adolescent brains in co-opting these regions into the face network.

  3. Assays for predicting and monitoring responses to lung cancer immunotherapy

    Institute of Scientific and Technical Information of China (English)

    Cristina Teixid; Niki Karachaliou; Maria Gonzlez-Cao; Daniela Morales-Espinosa; Rafael Rosell

    2015-01-01

    AbstrAct Immunotherapy has become a key strategy for cancer treatment, and two immune checkpoints, namely, programmed cell death 1 (PD-1) and its ligand (PD-L1), have recently emerged as important targets. hTe interaction blockade of PD-1 and PD-L1 demonstrated promising activity and antitumor effcacy in early phase clinical trials for advanced solid tumors such as non-small cell lung cancer (NSCLC). Many cell types in multiple tissues express PD-L1 as well as several tumor types, thereby suggesting that the ligand may play important roles in inhibiting immune responses throughout the body. hTerefore, PD-L1 is a critical immunomodulating component within the lung microenvironment, but the correlation between PD-L1 expression and prognosis is controversial. More evidence is required to support the use of PD-L1 as a potential predictive biomarker. Clinical trials have measured PD-L1 in tumor tissues by immunohistochemistry (IHC) with different antibodies, but the assessment of PD-L1 is not yet standardized. Some commercial antibodies lack speciifcity and their reproducibility has not been fully evaluated. Further studies are required to clarify the optimal IHC assay as well as to predict and monitor the immune responses of the PD-1/PD-L1 pathway.

  4. Comparison of cochlear delay estimates using otoacoustic emissions and auditory brainstem responses

    DEFF Research Database (Denmark)

    Harte, James; Pigasse, Gilles; Dau, Torsten

    2009-01-01

    Different attempts have been made to directly measure frequency specific basilar membrane (BM) delays in animals, e.g., laser velocimetry of BM vibrations and auditory nerve fiber recordings. The present study uses otoacoustic emissions (OAEs) and auditory brainstem responses (ABRs) to estimate B...... and synaptic delays. This allows a comparison between individual OAE and BM delays over a large frequency range in the same subjects, and offers support to the theory that OAEs are reflected from a tonotopic place and carried back to the cochlear base via a reverse traveling wave....

  5. Prediction of placebo responses: A systematic review of the literature

    Directory of Open Access Journals (Sweden)

    Bjoern eHoring

    2014-10-01

    Full Text Available Objective: Predicting who responds to placebo treatment – and under which circumstances – has been a question of interest and investigation for generations. However, the literature is disparate and inconclusive. This review aims to identify publications that provide high quality data on the topic of placebo response (PR prediction. Methods: To identify studies concerned with PR prediction, independent searches were performed in an expert database (for all symptom modalities and in PubMed (for pain only. Articles were selected when a they assessed putative predictors prior to placebo treatment and b an adequate control group was included when the association of predictors and PRs were analyzed. Results: Twenty-one studies were identified, most with pain as dependent variable. Most predictors of PRs were psychological constructs related to actions, expected outcomes and the emotional valence attached to these events (goal-seeking, self-efficacy/-esteem, locus of control, optimism. Other predictors involved behavioural control (desire for control, eating restraint, personality variables (fun seeking, sensation seeking, neuroticism, biological markers (sex, a single nucleotide polymorphism related to dopamine metabolism. Finally, suggestibility and beliefs in expectation biases, body consciousness and baseline symptom severity were found to be predictive. Conclusions: While results are heterogeneous, some congruence of predictors can be identified. PRs mainly appear to be moderated by expectations of how the symptom might change after treatment, or the expectation of how symptom repetition can be coped with. It is suggested to include the listed constructs in future research. Furthermore, a closer look at variables moderating symptom change in control groups seems warranted.

  6. Predicting the Response of the Mars Ionosphere to Solar Flares

    Science.gov (United States)

    Fallows, K.; Withers, P.; Gonzalez, G.

    2015-12-01

    The increased soft X-ray irradiance during solar flares generates increased electron densities in the lower ionosphere of Mars. The relative changes in electron density during a flare are greater for larger flares and also at lower altitudes and larger flares, due to the wavelength dependence of both the flux increase during the flare and the absorption of flux by the neutral atmosphere. These relationships have been explored [Bougher et al. 2001, Fox et al. 2004, Mendillo et al. 2006, Mahajan et al. 2011, Lollo et al. 2012] but not quantified, which has impeded the validation of simulations of the ionospheric effects of solar flares. Such simulations are necessary for developing accurate descriptions of the physical processes governing ionospheric behavior under extreme conditions. We present a response function, a mathematical expression for the change in electron density during a solar flare as a function of the change in solar flux and an optical depth proxy. This response function is based on analysis of 20 Mars Global Surveyor (MGS) radio occultation electron density profiles measured during solar flares. Characterizing the response as a function of optical depth, rather than altitude, provides the best description of ionospheric variability during a flare; otherwise non-negligible solar zenith angle effects are present. We demonstrate that the response function can be used to predict ionospheric electron densities during a specified solar flare by reproducing profiles known to be disturbed by a solar flare. We also demonstrate that the response function can be used to infer the strength of solar flares not visible at Earth by finding the flux enhancement required to reproduce an apparently flare affected profile given an undisturbed profile on the same date.

  7. Plume trajectory prediction for use in radiological emergency response planning

    International Nuclear Information System (INIS)

    The SAI multi puff steered plume model was developed for the State of Illinois to aid in emergency response planning. The plume is driven by either user input meteorological data or real-time remote tower data. Realistic steering is accomplished by dividing the plume into small puffs, each of which is individually responsive to wind direction changes. The steered plume is displayed against a topographical background on plotters and color graphics terminals. The background maps, showing realistic local details such as towns and rivers, may be varied both by scale and by amount of detail requested, including an emergency zone overlay. Up to ten contour levels representing nuclide concentrations and various exposure modes may be displayed. A sample scenario is discussed involving a hypothetical non-continuous release under changing meteorological conditions. Slides showing the progress of the plume and displaying contours of gamma dose rate and gamma dose are presented. The Illinois Department of Nuclear Safety emergency response actions for this sample scenario are discussed. The recommendations for evacuation of shelter are based on the predicted doses within specified zones. After an incident, decisions must be made about reentry based in part on deposition and ingestion pathways. Slides showing contour plots of these quantities are shown and the results plotted are analyzed from the point of view of emergency planning

  8. The multiform motor cortical output: Kinematic, predictive and response coding.

    Science.gov (United States)

    Sartori, Luisa; Betti, Sonia; Chinellato, Eris; Castiello, Umberto

    2015-09-01

    Observing actions performed by others entails a subliminal activation of primary motor cortex reflecting the components encoded in the observed action. One of the most debated issues concerns the role of this output: Is it a mere replica of the incoming flow of information (kinematic coding), is it oriented to anticipate the forthcoming events (predictive coding) or is it aimed at responding in a suitable fashion to the actions of others (response coding)? The aim of the present study was to disentangle the relative contribution of these three levels and unify them into an integrated view of cortical motor coding. We combined transcranial magnetic stimulation (TMS) and electromyography recordings at different timings to probe the excitability of corticospinal projections to upper and lower limb muscles of participants observing a soccer player performing: (i) a penalty kick straight in their direction and then coming to a full stop, (ii) a penalty kick straight in their direction and then continuing to run, (iii) a penalty kick to the side and then continuing to run. The results show a modulation of the observer's corticospinal excitability in different effectors at different times reflecting a multiplicity of motor coding. The internal replica of the observed action, the predictive activation, and the adaptive integration of congruent and non-congruent responses to the actions of others can coexist in a not mutually exclusive way. Such a view offers reconciliation among different (and apparently divergent) frameworks in action observation literature, and will promote a more complete and integrated understanding of recent findings on motor simulation, motor resonance and automatic imitation. PMID:25727547

  9. Modeling of Cancer Stem Cell State Transitions Predicts Therapeutic Response.

    Directory of Open Access Journals (Sweden)

    Mary E Sehl

    Full Text Available Cancer stem cells (CSCs possess capacity to both self-renew and generate all cells within a tumor, and are thought to drive tumor recurrence. Targeting the stem cell niche to eradicate CSCs represents an important area of therapeutic development. The complex nature of many interacting elements of the stem cell niche, including both intracellular signals and microenvironmental growth factors and cytokines, creates a challenge in choosing which elements to target, alone or in combination. Stochastic stimulation techniques allow for the careful study of complex systems in biology and medicine and are ideal for the investigation of strategies aimed at CSC eradication. We present a mathematical model of the breast cancer stem cell (BCSC niche to predict population dynamics during carcinogenesis and in response to treatment. Using data from cell line and mouse xenograft experiments, we estimate rates of interconversion between mesenchymal and epithelial states in BCSCs and find that EMT/MET transitions occur frequently. We examine bulk tumor growth dynamics in response to alterations in the rate of symmetric self-renewal of BCSCs and find that small changes in BCSC behavior can give rise to the Gompertzian growth pattern observed in breast tumors. Finally, we examine stochastic reaction kinetic simulations in which elements of the breast cancer stem cell niche are inhibited individually and in combination. We find that slowing self-renewal and disrupting the positive feedback loop between IL-6, Stat3 activation, and NF-κB signaling by simultaneous inhibition of IL-6 and HER2 is the most effective combination to eliminate both mesenchymal and epithelial populations of BCSCs. Predictions from our model and simulations show excellent agreement with experimental data showing the efficacy of combined HER2 and Il-6 blockade in reducing BCSC populations. Our findings will be directly examined in a planned clinical trial of combined HER2 and IL-6 targeted

  10. Prestimulation phase predicts the TMS-evoked response.

    Science.gov (United States)

    Kundu, Bornali; Johnson, Jeffrey S; Postle, Bradley R

    2014-10-15

    Prestimulation oscillatory phase and power in particular frequency bands predict perception of at-threshold visual stimuli and of transcranial magnetic stimulation (TMS)-induced phosphenes. These effects may be due to changes in cortical excitability, such that certain ranges of power and/or phase values result in a state in which a particular brain area is more receptive to input, thereby biasing behavior. However, the effects of trial-by-trial fluctuations in phase and power of ongoing oscillations on the brain's electrical response to TMS itself have thus far not been addressed. The present study adopts a combined TMS and electroencepalography (EEG) approach to determine whether the TMS-evoked response is sensitive to momentary fluctuations in prestimulation phase and/or power in different frequency bands. Specifically, TMS was applied to superior parietal lobule while subjects performed a short-term memory task. Results showed that the prestimulation phase, particularly within the beta (15-25 Hz) band, predicted pulse-by-pulse variations in the global mean field amplitude. No such relationship was observed between prestimulation power and the global mean field amplitude. Furthermore, TMS-evoked power in the beta band fluctuated with prestimulation phase in the beta band in a manner that differed from spontaneous brain activity. These effects were observed in areas at and distal to the stimulation site. Together, these results confirm the idea that fluctuating phase of ongoing neuronal oscillations create "windows of excitability" in the brain, and they give insight into how TMS interacts with ongoing brain activity on a pulse-by-pulse basis.

  11. Aggression predicts Cortisol Awakening Response in healthy young adults

    Directory of Open Access Journals (Sweden)

    Patricia Sariñana-González

    2015-10-01

    Full Text Available It seems that aggressive behavior is negatively related to cortisol (C, but this relationship has been established considering the evening C levels. On the other hand, the relationship with the C awakening response (CAR and the influence of gender and menstrual cycle phase are not well understood. This study analyzed this relationship in 83 women (38 in the luteal and 45 in the follicular phase of their menstrual cycle and 20 men. CAR was assessed by measuring salivary free cortisol levels in samples taken immediately following awakening and 30, 45, and 60 minutes later. Additionally, participants completed a self-report of aggression. Men presented lower CAR than women in the luteal phase. Moreover, they also had higher levels of physical aggression than women, independently of their menstrual phase. Regarding the relationships between variables, in men general aggression and verbal aggression predicted the CAR. In women, verbal aggression predicted the CAR during the follicular phase, whereas anger and physical aggression were predictors during the luteal phase. Our data support the view that there is a negative relationship between C and aggressive behavior, even during the morning, this relationship being moderated by gender and menstrual cycle phase in the women. These findings may help improve our understanding of the biological mechanisms involved in violence.

  12. The markers predicting response to Hepatitis C virus treatment and evaluation of treatment responses

    Directory of Open Access Journals (Sweden)

    Özgür Günal

    2012-09-01

    Full Text Available Objectives: Currently pegylated interferon alpha (peg-IFN and ribavirin treatment is recommended for chronic hepatitis Ctreatment. The aim of treatment is to provide sustained viral response (SVR.Material and methods: A total of 125 patients, who have been treated for chronic hepatitis C diagnosis and are followed upuntil 6 months after treatment, were enrolled into the study. Markers, which have indicated treatment response against hepatitisC virus treatment, treatment responses according to peg-IFNα type used, and experienced side effects in patients havebeen compared.Results: Of patients, 103 were (82.4% female and 22 were (17.6% male and mean of age was 54.74±7.93 years. Markersindicating SVR in our study were calculated as rapid viral response (RVR (p2 (p<0.034. Predictive parameters for EVR in our studywere defined as absence of diabetes in patients, high baseline lymphocyte numbers (2024.74±625.93 and high baseline cholesterollevel (in EVR positive patients 180.47±32.77 mg/dl; in EVR negatives 152.00±24.56. There was no statistical differencebetween peg-IFN type in patients and RVR, EVR and SVR. Also there was no statistical difference in hematological side effects(neutropenia, anemia, and thrombocytopenia in both treatment groups.Conclusions: As the efficacy of treatment against HCV is defined, predictive markers for the treatment response are becomingmore significant. Therefore, it is concluded that these factors should also be considered in patient treatment plans. J MicrobiolInfect Dis 2012; 2(3: 100-108Key words: Treatment of Hepatitis C, Sustained Viral Response, Markers of Treatment

  13. NEURAL NETWORKS PREDICTION FOR SEISMIC RESPONSE OF STRUCTURE UNDER THE LEVENBERG-MARQUARDT ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    徐赵东; 沈亚鹏; 李爱群

    2003-01-01

    Objective To investigate the prediction effect of neural networks for seismic response of structure under the Levenberg-Marquardt(LM) algorithm. Results Based on identification and prediction ability of neural networks for nonlinear systems, and combined with LM algorithm, a multi-layer forward networks is adopted to predict the seismic responses of structure. The networks is trained in batch by the shaking table test data of three-floor reinforced concrete structure firstly, then the seismic responses of structure are predicted under the unused excitation data, and the predict responses are compared with the experiment responses. The error curves between the prediction and the experimental results show the efficiency of the method. Conclusion LM algorithm has very good convergence rate, and the neural networks can predict the seismic response of the structure well.

  14. PREDICTS: Projecting Responses of Ecological Diversity in Changing Terrestrial Systems

    Directory of Open Access Journals (Sweden)

    Georgina Mace

    2012-12-01

    Full Text Available The PREDICTS project (www.predicts.org.uk is a three-year NERC-funded project to model and predict at a global scale how local terrestrial diversity responds to human pressures such as land use, land cover, pollution, invasive species and infrastructure. PREDICTS is a collaboration between Imperial College London, the UNEP World Conservation Monitoring Centre, Microsoft Research Cambridge, UCL and the University of Sussex. In order to meet its aims, the project relies on extensive data describing the diversity and composition of biological communities at a local scale. Such data are collected on a vast scale through the committed efforts of field ecologists. If you have appropriate data that you would be willing to share with us, please get in touch (enquiries@predicts.org.uk. All contributions will be acknowledged appropriately and all data contributors will be included as co-authors on an open-access paper describing the database.

  15. Method discussion for quick response grey prediction of stronger aftershocks of an earthquake sequence

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    In this paper, we take occurrence process of early strong aftershocks of a main-after shock type′s earthquake sequence as a complex grey system, and introduce predicting method for its stronger aftershocks by grey predicting theory. Through inspection prediction for 1998 Zhangbei MS=6.2 earthquake sequence, it shows that the grey predicting method maybe has active significance for the investigation of quick response prediction problems of stronger aftershocks of an earthquake sequence.

  16. Predicting the Response of Shear-critical Reinforced Concrete Beams using Response-2000 and SNI 2847:2013

    Directory of Open Access Journals (Sweden)

    Suryanto B.

    2016-03-01

    Full Text Available This study investigates the accuracy of Response-2000 in predicting the response of shear-critical reinforced concrete beams. The experimental data selected was that obtained by Vecchio and Shim in 2004 on twelve reinforced concrete beams which sought to replicate beams originally tested by Bresler and Scordelis in the early 1960s. This study also aims to compare the results obtained to the predictions of SNI 2847:2013. It is demonstrated that Response-2000 is capable of providing accurate predictions of load-deflection responses up to the peak load, but underestimates the ductility of beams that exhibit a mixed flexure-shear failure mode. It is also shown that both methods provide conservative predictions of the shear strength of beams with no shear reinforcement, with the software providing more consistent and reliable predictions of shear strength of beams containing shear reinforcement.

  17. Prepotent response inhibition predicts treatment outcome in attention deficit/hyperactivity disorder

    NARCIS (Netherlands)

    S. van der Oord; H.M. Geurts; P.J.M. Prins; P.M.G. Emmelkamp; J. Oosterlaan

    2012-01-01

    Objective: Inhibition deficits, including deficits in prepotent response inhibition and interference control, are core deficits in ADHD. The predictive value of prepotent response inhibition and interference control was assessed for outcome in a 10-week treatment trial with methylphenidate. Methods:

  18. Development and evaluation of a new method for predicting aircraft buffet response

    Science.gov (United States)

    Cunningham, A. M., Jr.; Waner, P. G., Jr.; Watts, J. D.; Benepe, D. B.; Riddle, D. W.

    1975-01-01

    The buffet prediction method uses rigid wind tunnel model fluctuating pressure data to form a buffet forcing function. The response is then calculated with a mathematical dynamic model of the airplane developed for gust response analysis. By including the extremes of phasing and contribution of symmetric and antisymmetric airplane responses, the upper and lower bounds are established for buffet response. F-111A flight test data show good agreement with predicted bounds for a variety of flight conditions.

  19. Prediction of First-Order Vessel Responses with Applications to Decision Support Systems

    DEFF Research Database (Denmark)

    Nielsen, Ulrik D.; Iseki, Toshio

    2015-01-01

    The paper presents a practical and simple approach for making vessel response predictions. Features of the procedure include a) predictions which are scaled so to better agree with corresponding true, future values to be measured at the time the predictions apply at; and b) predictions that are a......The paper presents a practical and simple approach for making vessel response predictions. Features of the procedure include a) predictions which are scaled so to better agree with corresponding true, future values to be measured at the time the predictions apply at; and b) predictions...... that are assigned an uncertainty measure to reflect a level of confidence. The approach is tested with full-scale data and the obtained results/predictions agree well with measured values. Potentially, the procedure is therefore very useful in future developments of general decision support systems....

  20. Ovarian response prediction in GnRH antagonist treatment for IVF using anti-Mullerian hormone

    NARCIS (Netherlands)

    Hamdine, O.; Eijkemans, M.J.; Lentjes, E.W.; Torrance, H.L.; Macklon, N.S.; Fauser, B.C.; Broekmans, F.J.

    2015-01-01

    STUDY QUESTION: What is the clinical value of anti-Mullerian hormone (AMH) for the prediction of high or low ovarian response in controlled ovarian stimulation for IVF using GnRH antagonist treatment? SUMMARY ANSWER: AMH as a single test has substantial accuracy for ovarian response prediction in Gn

  1. Regeneration of the auditory nerve - a cell transplantation study

    OpenAIRE

    Palmgren, Björn

    2011-01-01

    Since in mammals, the hair cells or the spiral ganglion neurons (SGNs) in the inner ear do not regenerate, damage to these cells is an irreversible process. Presently the only aid for patients with severe to profound hearing impairment due to damaged hair cells is a cochlear implant (CI). A CI converts sound to electrical signals that stimulate the SGNs via an electrode that is implanted into the cochlea. Hence, for a successful outcome the CI is dependant on the activation ...

  2. Predicting fluid responsiveness with transthoracic echocardiography is not yet evidence based

    DEFF Research Database (Denmark)

    Wetterslev, M; Haase, N; Johansen, R R;

    2013-01-01

    an integrated tool in the intensive care unit, this systematic review examined studies evaluating the predictive value of TTE for fluid responsiveness. In October 2012, we searched Pubmed, EMBASE and Web of Science for studies evaluating the predictive value of TTE-derived variables for fluid responsiveness...... responsiveness. Of the 4294 evaluated citations, only one study fully met our inclusion criteria. In this study, the predictive value of variations in inferior vena cava diameter (> 16%) for fluid responsiveness was moderate with sensitivity of 71% [95% confidence interval (CI) 44-90], specificity of 100% (95...

  3. Attachment avoidance predicts inflammatory responses to marital conflict

    OpenAIRE

    Gouin, Jean-Philippe; Glaser, Ronald; Loving, Timothy J.; Malarkey, William B.; Stowell, Jeffrey; Houts, Carrie; Kiecolt-Glaser, Janice K.

    2008-01-01

    Marital stress has been associated with immune dysregulation, including increased production of interleukin-6 (IL-6). Attachment style, one’s expectations about the availability and responsiveness of others in intimate relationships, appears to influence physiological stress reactivity and thus could influence inflammatory responses to marital conflict. Thirty-five couples were invited for two 24-hour admissions to a hospital research unit. The first visit included a structured social support...

  4. Predicting reinforced concrete frame response to excavation induced settlement

    OpenAIRE

    Laefer, Debra F.; Ceribasi, Seyit; James H Long; Cording, Edward J.

    2009-01-01

    In many tunneling and excavation projects, free-field vertical ground movements have been used to predict subsidence and empirical limits have been employed to evaluate risk. Validity of such approaches given the reality of two-dimensional ground movements and the influence of adjacent applied loads has been largely unknown. This paper employed analytical and large-scale experimental efforts to quantify these issues, in the case of a reinforced concrete frame structure adjacent to an excavati...

  5. Using unknown knowns to predict coastal response to future climate

    Science.gov (United States)

    Plant, N. G.; Lentz, E. E.; Gutierrez, B.; Thieler, E. R.; Passeri, D. L.

    2015-12-01

    The coastal zone, including its bathymetry, topography, ecosystem, and communities, depends on and responds to a wide array of natural and engineered processes associated with climate variability. Climate affects the frequency of coastal storms, which are only resolved probabilistically for future conditions, as well as setting the pace for persistent processes (e.g., waves driving daily alongshore transport; beach nourishment). It is not clear whether persistent processes or extreme events contribute most to the integrated evolution of the coast. Yet, observations of coastal change record the integration of persistent and extreme processes. When these observations span a large spatial domain and/or temporal range they may reflect a wide range of forcing and boundary conditions that include different levels of sea-level rise, storminess, sediment input, engineering activities, and elevation distributions. We have been using a statistical approach to characterize the interrelationships between oceanographic, ecological, and geomorphic processes—including the role played by human activities via coastal protection, beach nourishment, and other forms of coastal management. The statistical approach, Bayesian networks, incorporates existing information to establish underlying prior expectations for the distributions and inter-correlations of variables most relevant to coastal geomorphic evolution. This underlying information can then be used to make predictions. We demonstrate several examples of the utility of this approach using data as constraints and then propagating the constraints and uncertainty to make predictions of unobserved variables that include changes in shorelines, dunes, and overwash deposits. We draw on data from the Gulf and Atlantic Coasts of the United States, resolving time scales of years to a century. The examples include both short-term storm impacts and long-term evolution associated with sea-level rise. We show that the Bayesian network can

  6. 5-HTTLPR differentially predicts brain network responses to emotional faces

    DEFF Research Database (Denmark)

    Fisher, Patrick M; Grady, Cheryl L; Madsen, Martin K;

    2015-01-01

    resonance imaging in 76 healthy adults. We observed robust increased response to emotional faces in the amygdala, hippocampus, caudate, fusiform gyrus, superior temporal sulcus and lateral prefrontal and occipito-parietal cortices. We observed dissociation between 5-HTTLPR groups such that LA LA individuals...

  7. Mothers' Labeling Responses to Infants' Gestures Predict Vocabulary Outcomes

    Science.gov (United States)

    Olson, Janet; Masur, Elise Frank

    2015-01-01

    Twenty-nine infants aged 1;1 and their mothers were videotaped while interacting with toys for 18 minutes. Six experimental stimuli were presented to elicit infant communicative bids in two communicative intent contexts--proto-declarative and proto-imperative. Mothers' verbal responses to infants' gestural and non-gestural communicative bids were…

  8. Global genetic variations predict brain response to faces

    DEFF Research Database (Denmark)

    Dickie, Erin W; Tahmasebi, Amir; French, Leon;

    2014-01-01

    Face expressions are a rich source of social signals. Here we estimated the proportion of phenotypic variance in the brain response to facial expressions explained by common genetic variance captured by ∼ 500,000 single nucleotide polymorphisms. Using genomic-relationship-matrix restricted maximu...

  9. COMT val158met predicts reward responsiveness in humans.

    Science.gov (United States)

    Lancaster, T M; Linden, D E; Heerey, E A

    2012-11-01

    A functional variant of the catechol-O-methyltransferase (COMT) gene [val158met (rs4680)] is frequently implicated in decision-making and higher cognitive functions. It may achieve its effects by modulating dopamine-related decision-making and reward-guided behaviour. Here we demonstrate that individuals with the met/met polymorphism have greater responsiveness to reward than carriers of the val allele and that this correlates with risk-seeking behaviour. We assessed performance on a reward responsiveness task and the Balloon analogue risk task, which measure how participants (N = 70, western European, university and postgraduate students) respond to reward and take risks in the presence of available reward. Individuals with the met/met genotype (n = 19) showed significantly higher reward responsiveness, F2,64 = 4.02, P = 0.02, and reward-seeking behaviour, F(2,68) = 4.52, P = 0.01, than did either val/met (n = 25) or val/val (n = 26) carriers. These results highlight a scenario in which genotype-dependent reward responsiveness shapes reward-seeking, therefore suggesting a novel framework by which COMT may modulate behaviour. PMID:22900954

  10. Prediction of response to interferon therapy in multiple sclerosis

    DEFF Research Database (Denmark)

    Sellebjerg, F; Søndergaard, Helle Bach; Koch-Henriksen, N;

    2014-01-01

    OBJECTIVE: Single nucleotide polymorphisms (SNPs) in the genes encoding interferon response factor (IRF)-5, IRF-8 and glypican-5 (GPC5) have been associated with disease activity in multiple sclerosis (MS) patients treated with interferon (IFN)-β. We analysed whether SNPs in the IRF5, IRF8 and GPC5...

  11. Immune response markers in sentinel nodes may predict melanoma progression

    OpenAIRE

    Rodolfo, Monica; Castelli, Chiara; Rivoltini, Licia

    2014-01-01

    We recently reported that variable expression of immune-response genes distinguishes tumor positive sentinel nodes in melanoma patients with malignant progression from those with non-progressing disease. Our results depict sentinel nodes as sites in which immune functions are associated with metastatic disease and identify CD30 as a host immune-related cancer prognostic marker and potential therapeutic target.

  12. Predicting nonlinear properties of metamaterials from the linear response.

    Science.gov (United States)

    O'Brien, Kevin; Suchowski, Haim; Rho, Junsuk; Salandrino, Alessandro; Kante, Boubacar; Yin, Xiaobo; Zhang, Xiang

    2015-04-01

    The discovery of optical second harmonic generation in 1961 started modern nonlinear optics. Soon after, R. C. Miller found empirically that the nonlinear susceptibility could be predicted from the linear susceptibilities. This important relation, known as Miller's Rule, allows a rapid determination of nonlinear susceptibilities from linear properties. In recent years, metamaterials, artificial materials that exhibit intriguing linear optical properties not found in natural materials, have shown novel nonlinear properties such as phase-mismatch-free nonlinear generation, new quasi-phase matching capabilities and large nonlinear susceptibilities. However, the understanding of nonlinear metamaterials is still in its infancy, with no general conclusion on the relationship between linear and nonlinear properties. The key question is then whether one can determine the nonlinear behaviour of these artificial materials from their exotic linear behaviour. Here, we show that the nonlinear oscillator model does not apply in general to nonlinear metamaterials. We show, instead, that it is possible to predict the relative nonlinear susceptibility of large classes of metamaterials using a more comprehensive nonlinear scattering theory, which allows efficient design of metamaterials with strong nonlinearity for important applications such as coherent Raman sensing, entangled photon generation and frequency conversion.

  13. Trend modelling of wave parameters and application in onboard prediction of ship responses

    DEFF Research Database (Denmark)

    Montazeri, Najmeh; Nielsen, Ulrik Dam; Jensen, J. Juncher

    2015-01-01

    This paper presents a trend analysis for prediction of sea state parameters onboard shipsduring voyages. Given those parameters, a JONSWAP model and also the transfer functions, prediction of wave induced ship responses are thus made. The procedure is tested with full-scale data of an in-service ......This paper presents a trend analysis for prediction of sea state parameters onboard shipsduring voyages. Given those parameters, a JONSWAP model and also the transfer functions, prediction of wave induced ship responses are thus made. The procedure is tested with full-scale data of an in...

  14. Predicting Ecosystem Response to Perturbation from Thermodynamic Criteria

    OpenAIRE

    Michaelian, K.; Chavez, V. Alonso

    2008-01-01

    The response of ecosystems to perturbations is considered from a thermodynamic perspective by acknowledging that, as for all macroscopic systems and processes, the dynamics and stability of ecosystems is subject to definite thermodynamic law. For open ecosystems, exchanging energy, work, and mass with the environment, the thermodynamic criteria come from non-equilibrium or irreversible thermodynamics. For ecosystems during periods in which the boundary conditions may be considered as being co...

  15. Random Forests for Ordinal Response Data: Prediction and Variable Selection

    OpenAIRE

    Janitza, Silke; Tutz, Gerhard; Boulesteix, Anne-Laure

    2014-01-01

    The random forest method is a commonly used tool for classification with high-dimensional data that is able to rank candidate predictors through its inbuilt variable importance measures (VIMs). It can be applied to various kinds of regression problems including nominal, metric and survival response variables. While classification and regression problems using random forest methodology have been extensively investigated in the past, there seems to be a lack of literature on handling ordinal re...

  16. Aggression predicts Cortisol Awakening Response in healthy young adults

    OpenAIRE

    Patricia Sariñana-González; Ángel Romero-Martínez; Luis Moya-Albiol

    2015-01-01

    It seems that aggressive behavior is negatively related to cortisol (C), but this relationship has been established considering the evening C levels. On the other hand, the relationship with the C awakening response (CAR) and the influence of gender and menstrual cycle phase are not well understood. This study analyzed this relationship in 83 women (38 in the luteal and 45 in the follicular phase of their menstrual cycle) and 20 men. CAR was assessed by measuring salivary free cortisol levels...

  17. Attachment avoidance predicts inflammatory responses to marital conflict.

    Science.gov (United States)

    Gouin, Jean-Philippe; Glaser, Ronald; Loving, Timothy J; Malarkey, William B; Stowell, Jeffrey; Houts, Carrie; Kiecolt-Glaser, Janice K

    2009-10-01

    Marital stress has been associated with immune dysregulation, including increased production of interleukin-6 (IL-6). Attachment style, one's expectations about the availability and responsiveness of others in intimate relationships, appears to influence physiological stress reactivity and thus could influence inflammatory responses to marital conflict. Thirty-five couples were invited for two 24-h admissions to a hospital research unit. The first visit included a structured social support interaction, while the second visit comprised the discussion of a marital disagreement. A mixed effect within-subject repeated measure model indicated that attachment avoidance significantly influenced IL-6 production during the conflict visit but not during the social support visit. Individuals with higher attachment avoidance had on average an 11% increase in total IL-6 production during the conflict visit as compared to the social support visit, while individuals with lower attachment avoidance had, on average, a 6% decrease in IL-6 production during the conflict visit as compared to the social support visit. Furthermore, greater attachment avoidance was associated with a higher frequency of negative behaviors and a lower frequency of positive behaviors during the marital interaction, providing a mechanism by which attachment avoidance may influence inflammatory responses to marital conflict. In sum, these results suggest that attachment avoidance modulates marital behavior and stress-induced immune dysregulation. PMID:18952163

  18. Prediction of treatment week eight response & sustained virologic response in patients treated with boceprevir plus peginterferon alfa and ribavirin.

    Directory of Open Access Journals (Sweden)

    Alex Thompson

    Full Text Available AIM: Sustained virologic response (SVR can be attained with boceprevir plus peginterferon alfa and ribavirin (PR in up to 68% of patients, and short duration therapy is possible if plasma HCV RNA levels are undetectable at treatment week 8 (TW8 response. We have developed predictive models for SVR, and TW8 response using data from boceprevir clinical trials. METHODS: Regression models were built to predict TW8 response and SVR. Separate models were built for TW8 and SVR using baseline variables only, and compared to models with baseline variables plus HCV RNA change after 4 weeks of PR (TW4 delta. Predictive accuracy was assessed by c-statistics, calibration curves, and decision curve analyses. Nomograms were developed to create clinical decision support tools. Models were externally validated using independent data. RESULTS: The models that included TW4 delta produced the best discrimination ability. The predictive factors for TW8 response (n = 856 were TW4 delta, race, platelet count and ALT. The predictive factors for SVR (n = 522 were TW4 delta, HCV-subtype, gender, BMI, RBV dose and platelet count. The discrimination abilities of these models were excellent (C-statistics = 0.88, 0.80 respectively. Baseline models for TW8 response (n = 444 and SVR (n = 197 had weaker discrimination ability (C-statistic = 0.76, 0.69. External validation confirmed the predictive accuracy of the week 4 models. CONCLUSIONS: Models incorporating baseline and treatment week 4 data provide excellent prediction of TW8 response and SVR, and support the clinical utility of the lead-in phase of PR. The nomograms are suitable for point-of-care use to inform individual patient and physician decision-making.

  19. A Coupled Probabilistic Wake Vortex and Aircraft Response Prediction Model

    Science.gov (United States)

    Gloudemans, Thijs; Van Lochem, Sander; Ras, Eelco; Malissa, Joel; Ahmad, Nashat N.; Lewis, Timothy A.

    2016-01-01

    Wake vortex spacing standards along with weather and runway occupancy time, restrict terminal area throughput and impose major constraints on the overall capacity and efficiency of the National Airspace System (NAS). For more than two decades, the National Aeronautics and Space Administration (NASA) has been conducting research on characterizing wake vortex behavior in order to develop fast-time wake transport and decay prediction models. It is expected that the models can be used in the systems level design of advanced air traffic management (ATM) concepts that safely increase the capacity of the NAS. It is also envisioned that at a later stage of maturity, these models could potentially be used operationally, in groundbased spacing and scheduling systems as well as on the flight deck.

  20. Anger responses to psychosocial stress predict heart rate and cortisol stress responses in men but not women.

    Science.gov (United States)

    Lupis, Sarah B; Lerman, Michelle; Wolf, Jutta M

    2014-11-01

    While previous research has suggested that anger and fear responses to stress are linked to distinct sympathetic nervous system (SNS) stress responses, little is known about how these emotions predict hypothalamus-pituitary-adrenal (HPA) axis reactivity. Further, earlier research primarily relied on retrospective self-report of emotion. The current study aimed at addressing both issues in male and female individuals by assessing the role of anger and fear in predicting heart rate and cortisol stress responses using both self-report and facial coding analysis to assess emotion responses. We exposed 32 healthy students (18 female; 19.6±1.7 yr) to an acute psychosocial stress paradigm (TSST) and measured heart rate and salivary cortisol levels throughout the protocol. Anger and fear before and after stress exposure was assessed by self-report, and video recordings of the TSST were assessed by a certified facial coder to determine emotion expression (FACS). Self-reported emotions and emotion expressions did not correlate (all p>.23). Increases in self-reported fear predicted blunted cortisol responses in men (β=0.41, p=.04). Also for men, longer durations of anger expression predicted exaggerated cortisol responses (β=0.67 p=.004), and more anger incidences predicted exaggerated cortisol and heart rate responses (β=0.51, p=.033; β=0.46, p=.066, resp.). Anger and fear did not predict SNS or HPA activity for females (all p>.23). The current differential self-report and facial coding findings support the use of multiple modes of emotion assessment. Particularly, FACS but not self-report revealed a robust anger-stress association that could have important downstream health effects for men. For women, future research may clarify the role of other emotions, such as self-conscious expressions of shame, for physiological stress responses. A better understanding of the emotion-stress link may contribute to behavioral interventions targeting health-promoting ways of

  1. Western Mountain Initiative: predicting ecosystem responses to climate change

    Science.gov (United States)

    Baron, Jill S.; Peterson, David L.; Wilson, J.T.

    2008-01-01

    Mountain ecosystems of the western United States provide irreplaceable goods and services such as water, timber, biodiversity, and recreational opportunities, but their responses to climatic changes are complex and not well understood. The Western Mountain Initiative (WMI), a collaboration between USGS and U.S. Forest Service scientists, catalyzes assessment and synthesis of the effects of disturbance and climate change across western mountain areas, focusing on national parks and surrounding national forests. The WMI takes an ecosystem approach to science, integrating research across science disciplines at scales ranging from field studies to global trends.

  2. Individual Differences in Gelotophobia Predict Responses to Joy and Contempt

    Directory of Open Access Journals (Sweden)

    Jennifer Hofmann

    2015-04-01

    Full Text Available In a paradigm facilitating smile misattribution, facial responses and ratings to contempt and joy were investigated in individuals with or without gelotophobia (fear of being laughed at. Participants from two independent samples (N1 = 83, N2 = 50 rated the intensity of eight emotions in 16 photos depicting joy, contempt, and different smiles. Facial responses were coded by the Facial Action Coding System in the second study. Compared with non-fearful individuals, gelotophobes rated joy smiles as less joyful and more contemptuous. Moreover, gelotophobes showed less facial joy and more contempt markers. The contempt ratings were comparable between the two groups. Looking at the photos of smiles lifted the positive mood of non-gelotophobes, whereas gelotophobes did not experience an increase. We hypothesize that the interpretation bias of “joyful faces hiding evil minds” (i.e., being also contemptuous and exhibiting less joy facially may complicate social interactions for gelotophobes and serve as a maintaining factor of gelotophobia.

  3. Improving models to predict phenological responses to global change

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Andrew D. [Harvard College, Cambridge, MA (United States)

    2015-11-25

    The term phenology describes both the seasonal rhythms of plants and animals, and the study of these rhythms. Plant phenological processes, including, for example, when leaves emerge in the spring and change color in the autumn, are highly responsive to variation in weather (e.g. a warm vs. cold spring) as well as longer-term changes in climate (e.g. warming trends and changes in the timing and amount of rainfall). We conducted a study to investigate the phenological response of northern peatland communities to global change. Field work was conducted at the SPRUCE experiment in northern Minnesota, where we installed 10 digital cameras. Imagery from the cameras is being used to track shifts in plant phenology driven by elevated carbon dioxide and elevated temperature in the different SPRUCE experimental treatments. Camera imagery and derived products (“greenness”) is being posted in near-real time on a publicly available web page (http://phenocam.sr.unh.edu/webcam/gallery/). The images will provide a permanent visual record of the progression of the experiment over the next 10 years. Integrated with other measurements collected as part of the SPRUCE program, this study is providing insight into the degree to which phenology may mediate future shifts in carbon uptake and storage by peatland ecosystems. In the future, these data will be used to develop improved models of vegetation phenology, which will be tested against ground observations collected by a local collaborator.

  4. Predicting the Response of Electricity Load to Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Patrick [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Colman, Jesse [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kalendra, Eric [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-07-28

    Our purpose is to develop a methodology to quantify the impact of climate change on electric loads in the United States. We perform simple linear regression, assisted by geospatial smoothing, on paired temperature and load time-series to estimate the heating- and coolinginduced sensitivity to temperature across 300 transmission zones and 16 seasonal and diurnal time periods. The estimated load sensitivities can be coupled with climate scenarios to quantify the potential impact of climate change on load, with a primary application being long-term electricity scenarios. The method allows regional and seasonal differences in climate and load response to be reflected in the electricity scenarios. While the immediate product of this analysis was designed to mesh with the spatial and temporal resolution of a specific electricity model to enable climate change scenarios and analysis with that model, we also propose that the process could be applied for other models and purposes.

  5. Camera response prediction for various capture settings using the spectral sensitivity and crosstalk model.

    Science.gov (United States)

    Qiu, Jueqin; Xu, Haisong

    2016-09-01

    In this paper, a camera response formation model is proposed to accurately predict the responses of images captured under various exposure settings. Differing from earlier works that estimated the camera relative spectral sensitivity, our model constructs the physical spectral sensitivity curves and device-dependent parameters that convert the absolute spectral radiances of target surfaces to the camera readout responses. With this model, the camera responses to miscellaneous combinations of surfaces and illuminants could be accurately predicted. Thus, creating an "imaging simulator" by using the colorimetric and photometric research based on the cameras would be of great convenience. PMID:27607275

  6. Camera response prediction for various capture settings using the spectral sensitivity and crosstalk model.

    Science.gov (United States)

    Qiu, Jueqin; Xu, Haisong

    2016-09-01

    In this paper, a camera response formation model is proposed to accurately predict the responses of images captured under various exposure settings. Differing from earlier works that estimated the camera relative spectral sensitivity, our model constructs the physical spectral sensitivity curves and device-dependent parameters that convert the absolute spectral radiances of target surfaces to the camera readout responses. With this model, the camera responses to miscellaneous combinations of surfaces and illuminants could be accurately predicted. Thus, creating an "imaging simulator" by using the colorimetric and photometric research based on the cameras would be of great convenience.

  7. A combined clinical and biomarker approach to predict diuretic response in acute heart failure

    NARCIS (Netherlands)

    Ter Maaten, Jozine M; Valente, Mattia A E; Metra, Marco; Bruno, Noemi; O'Connor, Christopher M; Ponikowski, Piotr; Teerlink, John R; Cotter, Gad; Davison, Beth; Cleland, John G; Givertz, Michael M; Bloomfield, Daniel M; Dittrich, Howard C; van Veldhuisen, Dirk J; Hillege, Hans L; Damman, Kevin; Voors, Adriaan A

    2015-01-01

    BACKGROUND: Poor diuretic response in acute heart failure is related to poor clinical outcome. The underlying mechanisms and pathophysiology behind diuretic resistance are incompletely understood. We evaluated a combined approach using clinical characteristics and biomarkers to predict diuretic resp

  8. Auditory Brainstem Response to Complex Sounds Predicts Self-Reported Speech-in-Noise Performance

    Science.gov (United States)

    Anderson, Samira; Parbery-Clark, Alexandra; White-Schwoch, Travis; Kraus, Nina

    2013-01-01

    Purpose: To compare the ability of the auditory brainstem response to complex sounds (cABR) to predict subjective ratings of speech understanding in noise on the Speech, Spatial, and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004) relative to the predictive ability of the Quick Speech-in-Noise test (QuickSIN; Killion, Niquette,…

  9. Measures of endothelial dysfunction predict response to cardiac resynchronisation therapy

    Science.gov (United States)

    Warriner, David R; Lawford, Patricia; Sheridan, Paul J

    2016-01-01

    Objectives Cardiac resynchronisation therapy (CRT) improves morbidity and mortality in heart failure (HF). Impaired endothelial function, as measured by flow-mediated dilation (FMD) is associated with increased morbidity and mortality in HF and may help to differentiate responders from non-responders. Methods 19 patients were recruited, comprising 94% men, mean age 69±8 years, New York Heart Association functional classes II–IV, QRSd 161±21 ms and mean left ventricular ejection fraction 26±8%. Markers of response and FMD were measured at baseline, 6 and 12 months following CRT. Results 14 patients were responders to CRT. Responders had significant improvements in VO2 (12.6±1.7 to 14.7±1.5 mL/kg/min, pFMD in responders was 2.9±1.9% and 7.4±3.73% in non-responders (pFMD. This study confirms that FMD identifies responders to CRT, due to endothelium-dependent mechanisms alone. PMID:27335654

  10. Pharmacogenetic approaches to the prediction of drug response

    International Nuclear Information System (INIS)

    The following review of pharmacogenetic progress and methodology is offered to stimulate and suggest analogous studies on drugs of abuse. It is readily acknowledged that formidable methodological problems are posed by adapting to drugs of abuse these pharmacogenetic approaches based on the administration of single safe doses of various prescription drugs to normal subjects under carefully controlled environmental conditions. Results of similarly designed studies on drugs of abuse in addicts might be uninterpretable because of confounding by numerous environmental perturbations, including the smoking of cigarettes and/or marijuana, nutritional variations, and intake of other drugs such as ethanol. Ethical considerations render objectionable the administration to unaddicted subjects of drugs at dosage levels usually ingested by drug abusers. Other approaches would have to be taken in such normal subjects. Possibilities include administration of tracer doses of /sup 14/C- or /sup 13/C- labeled drugs or growth of normal cells in culture to investigate their pharmacokinetic and/or pharmacodynamic responses to various drugs of abuse

  11. Predicting the response of a submillimeter bolometer to cosmic rays.

    Science.gov (United States)

    Woodcraft, Adam L; Sudiwala, Rashmi V; Ade, Peter A R; Griffin, Matthew J; Wakui, Elley; Bhatia, Ravinder S; Lange, Andrew E; Bock, James J; Turner, Anthony D; Yun, Minhee H; Beeman, Jeffrey W

    2003-09-01

    Bolometers designed to detect submillimeter radiation also respond to cosmic, gamma, and x rays. Because detectors cannot be fully shielded from such energy sources, it is necessary to understand the effect of a photon or cosmic-ray particle being absorbed. The resulting signal (known as a glitch) can then be removed from raw data. We present measurements using an Americium-241 gamma radiation source to irradiate a prototype bolometer for the High Frequency Instrument in the Planck Surveyor satellite. Our measurements showed no variation in response depending on where the radiation was absorbed, demonstrating that the bolometer absorber and thermistor thermalize quickly. The bolometer has previously been fully characterized both electrically and optically. We find that using optically measured time constants underestimates the time taken for the detector to recover from a radiation absorption event. However, a full thermal model for the bolometer, with parameters taken from electrical and optical measurements, provides accurate time constants. Slight deviations from the model were seen at high energies; these can be accounted for by use of an extended model. PMID:12962375

  12. Hazards Response of Energetic Materials - Developing a Predictive Capability for Initiation and Reaction under Multiple Stimuli

    Energy Technology Data Exchange (ETDEWEB)

    Nichols III, A L; Wallin, B K; Maienschein, J L; Reaugh, J E; Yoh, J J; McClelland, M E

    2005-04-15

    We present our approach to develop a predictive capability for hazards--thermal and nonshock impact--response of energetic material systems based on: (A) identification of relevant processes; (B) characterization of the relevant properties; (C) application of property data to predictive models; and (D) application of the models into predictive simulation. This paper focuses on the last two elements above, while a companion paper by Maienschein et al focuses on the first two elements. We outline models to describe the both the microscopic evolution of hot spots for detonation response and thermal kinetic models used to model slow heat environments. We show examples of application to both types of environments.

  13. Prediction models for platinum-based chemotherapy response and toxicity in advanced NSCLC patients.

    Science.gov (United States)

    Yin, Ji-Ye; Li, Xi; Li, Xiang-Ping; Xiao, Ling; Zheng, Wei; Chen, Juan; Mao, Chen-Xue; Fang, Chao; Cui, Jia-Jia; Guo, Cheng-Xian; Zhang, Wei; Gao, Yang; Zhang, Chun-Fang; Chen, Zi-Hua; Zhou, Hui; Zhou, Hong-Hao; Liu, Zhao-Qian

    2016-07-10

    In this study, we aimed to establish a platinum-based chemotherapy response and toxicity prediction model in advanced non-small cell lung cancer (NSCLC) patients. 416 single nucleotide polymorphisms (SNPs) in 185 genes were genotyped, and their association with drug response and toxicity were estimated using logistic regression. Nine data mining techniques were employed to establish the prediction model; the sensitivity, specificity, overall accuracy and receiver operating characteristic (ROC) curve were used to assess the models' performance. Finally, selected models were validated in an independent cohort. The models established by naïve Bayesian algorithm had the best performance. The response prediction model achieved a sensitivity of 0.90 and a specificity of 0.47 with the ROC area under curve (AUC) of 0.80. The overall toxicity prediction model achieved a sensitivity of 0.86 and a specificity of 0.46 with the ROC AUC of 0.73. The hematological toxicity prediction model achieved a sensitivity of 0.89 and a specificity of 0.39 with the ROC AUC of 0.76. The gastrointestinal toxicity prediction model achieved a sensitivity of 0.93 and a specificity of 0.35 with the ROC AUC of 0.80. In conclusion, we provided platinum-based chemotherapy response and toxicity prediction models for advanced NSCLC patients. PMID:27126360

  14. Prediction of lung function response for populations exposed to a wide range of ozone conditions

    Science.gov (United States)

    Abstract Context: A human exposure-response (E-R) model that has previously been demonstrated to accurately predict population mean FEV1 response to ozone exposure has been proposed as the foundation for future risk assessments for ambient ozone. Objective: Fit the origi...

  15. Exposure-response functions for (or versus?) the prediction of annoyance in specific situations

    NARCIS (Netherlands)

    Janssen, S.A.; Vos, H.

    2012-01-01

    Based on data from many surveys, exposure-response functions have been derived to describe the average expected annoyance response at a certain noise level. These have been used to define acceptable levels of environmental noise for separate noise sources. However, the prediction of the annoyance re

  16. Macrobenthic species response surfaces along estuarine gradients: prediction by logistic regression

    NARCIS (Netherlands)

    Ysebaert, T.; Meire, P.; Herman, P.M.J.; Verbeek, H.

    2002-01-01

    This study aims at contributing to the development of statistical models to predict macrobenthic species response to environmental conditions in estuarine ecosystems. Ecological response surfaces are derived for 10 estuarine macrobenthic species. Logistic regression is applied on a large data set, p

  17. Posterior Predictive Checks for Conditional Independence between Response Time and Accuracy

    Science.gov (United States)

    Bolsinova, Maria; Tijmstra, Jesper

    2016-01-01

    Conditional independence (CI) between response time and response accuracy is a fundamental assumption of many joint models for time and accuracy used in educational measurement. In this study, posterior predictive checks (PPCs) are proposed for testing this assumption. These PPCs are based on three discrepancy measures reflecting different…

  18. Prediction of hearing thresholds: Comparison of cortical evoked response audiometry and auditory steady state response audiometry techniques

    OpenAIRE

    Wong, LLN; Yeung, KNK

    2007-01-01

    The present study evaluated how well auditory steady state response (ASSR) and tone burst cortical evoked response audiometry (CERA) thresholds predict behavioral thresholds in the same participants. A total of 63 ears were evaluated. For ASSR testing, 100% amplitude modulated and 10% frequency modulated tone stimuli at a modulation frequency of 40Hz were used. Behavioral thresholds were closer to CERA thresholds than ASSR thresholds. ASSR and CERA thresholds were closer to behavioral thresho...

  19. Acceleration response spectrum for predicting floor vibration due to occupant walking

    Science.gov (United States)

    Chen, Jun; Xu, Ruotian; Zhang, Mengshi

    2014-07-01

    Annoying vibrations caused by occupant walking is an important serviceability problem for long-span floors. At the design stage the floor's structural arrangement may frequently change to cater for the owner's varying requirements. An efficient and accurate approach for predicting a floor's acceleration response is thus of great significance. This paper presents a design-oriented acceleration response spectrum for calculating a floor's response given the floor's modal characteristics and a specified confidence level. 2204 measured footfall traces from 61 test subjects were used to generate 10 s peak root-mean-square acceleration response spectra, on which a piecewise mathematical representation is based. The proposed response spectrum consists of three main parts: the first harmonic plateau ranging from 1.5 to 2.5 Hz, the second harmonic plateau ranging from 3.0 to 5.0 Hz and the descending part going with frequencies from 5.0 to 10.0 Hz. The representative value of each plateau and the mathematical representation for the descending curve were determined statistically for different confidence levels. Furthermore, the effects of factors, such as floor span, occupant stride length, higher modes of vibration, boundary conditions and peak acceleration response, on the proposed spectrum have been investigated and a modification measure for each factor is suggested. A detailed application procedure for the proposed spectrum approach is presented and has been applied to four existing floors to predict their acceleration responses. Comparison between predicted and field measured responses shows that the measured accelerations of the four floors are generally close to or slightly higher than the predicted values for the 75 percent confidence level, but are all lower than the predicted values for the 95 percent confidence level. Therefore the suggested spectrum-based approach can be used for predicting a floor's response subject to a single person walking.

  20. Predictive neural coding of reward preference involves dissociable responses in human ventral midbrain and ventral striatum.

    Science.gov (United States)

    O'Doherty, John P; Buchanan, Tony W; Seymour, Ben; Dolan, Raymond J

    2006-01-01

    Food preferences are acquired through experience and can exert strong influence on choice behavior. In order to choose which food to consume, it is necessary to maintain a predictive representation of the subjective value of the associated food stimulus. Here, we explore the neural mechanisms by which such predictive representations are learned through classical conditioning. Human subjects were scanned using fMRI while learning associations between arbitrary visual stimuli and subsequent delivery of one of five different food flavors. Using a temporal difference algorithm to model learning, we found predictive responses in the ventral midbrain and a part of ventral striatum (ventral putamen) that were related directly to subjects' actual behavioral preferences. These brain structures demonstrated divergent response profiles, with the ventral midbrain showing a linear response profile with preference, and the ventral striatum a bivalent response. These results provide insight into the neural mechanisms underlying human preference behavior. PMID:16387647

  1. Methods and kits for predicting a response to an erythropoietic agent

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Michael L.; Klein, Jon B.; Brier, Michael E.; Gaweda, Adam E.

    2015-06-16

    Methods for predicting a response to an erythropoietic agent in a subject include providing a biological sample from the subject, and determining an amount in the sample of at least one peptide selected from the group consisting of SEQ ID NOS: 1-17. If there is a measurable difference in the amount of the at least one peptide in the sample, when compared to a control level of the same peptide, the subject is then predicted to have a good response or a poor response to the erythropoietic agent. Kits for predicting a response to an erythropoietic agent are further provided and include one or more antibodies, or fragments thereof, that specifically recognize a peptide of SEQ ID NOS: 1-17.

  2. Does an understanding of ecosystems responses to rainfall pulses improve predictions of responses of drylands to climate change?

    Science.gov (United States)

    Drylands will experience more intense and frequent droughts and floods. Ten-year field experiments manipulating the amount and variability of precipitation suggest that we cannot predict responses of drylands to climate change based on pulse experimentation. Long-term drought experiments showed no e...

  3. Factors predictive of a beneficial response to therapy of hepatitis C.

    Science.gov (United States)

    Davis, G L; Lau, J Y

    1997-09-01

    Alpha interferon is the only drug that has been shown to be effective in the treatment of chronic hepatitis C, but only half of patients respond, either transiently or permanently. Pretreatment features that are associated with a greater likelihood of response to short courses of interferon include low hepatitis C virus (HCV) RNA levels, viral genotypes 2 or 3, and the absence of fibrosis or cirrhosis on liver biopsy. Each of these features is more predictive of sustained response (SR) than the end-of-treatment response (ETR). However, the accuracy of these features in predicting response in individual patients is poor. Furthermore, there are several limitations to using these factors in the clinical management of patients. Most importantly, they were identified in 6-month treatment trials. Longer treatment or combination of interferon with ribavirin reduces relapses and will therefore lessen the association of these factors with long-term response. In addition, changes in the definition of treatment end points and the technology used to measure HCV RNA might change the association between these predictive factors and response. The best predictor of a treatment response is the early normalization of the serum alanine aminotransferase (ALT) level during interferon treatment. HCV RNA loss during treatment may also be helpful in predicting response, but it is probably no better than serum ALT levels and is expensive. In summary, several clinical and virological features are associated with higher response rates to interferon treatment. Although pretreatment factors do not accurately predict treatment outcome in individuals, they may be helpful in counseling patients and making treatment decisions. PMID:9305676

  4. Evidence that conditioned avoidance responses are reinforced by positive prediction errors signaled by tonic striatal dopamine.

    Science.gov (United States)

    Dombrowski, Patricia A; Maia, Tiago V; Boschen, Suelen L; Bortolanza, Mariza; Wendler, Etieli; Schwarting, Rainer K W; Brandão, Marcus Lira; Winn, Philip; Blaha, Charles D; Da Cunha, Claudio

    2013-03-15

    We conducted an experiment in which hedonia, salience and prediction error hypotheses predicted different patterns of dopamine (DA) release in the striatum during learning of conditioned avoidance responses (CARs). The data strongly favor the latter hypothesis. It predicts that during learning of the 2-way active avoidance CAR task, positive prediction errors generated when rats do not receive an anticipated footshock (which is better than expected) cause DA release that reinforces the instrumental avoidance action. In vivo microdialysis in the rat striatum showed that extracellular DA concentration increased during early CAR learning and decreased throughout training returning to baseline once the response was well learned. In addition, avoidance learning was proportional to the degree of DA release. Critically, exposure of rats to the same stimuli but in an unpredictable, unavoidable, and inescapable manner, did not produce alterations from baseline DA levels as predicted by the prediction error but not hedonic or salience hypotheses. In addition, rats with a partial lesion of substantia nigra DA neurons, which did not show increased DA levels during learning, failed to learn this task. These data represent clear and unambiguous evidence that it was the factor positive prediction error, and not hedonia or salience, which caused increase in the tonic level of striatal DA and which reinforced learning of the instrumental avoidance response. PMID:22771418

  5. Predicting Ovarian Cancer Patients' Clinical Response to Platinum-Based Chemotherapy by Their Tumor Proteomic Signatures.

    Science.gov (United States)

    Yu, Kun-Hsing; Levine, Douglas A; Zhang, Hui; Chan, Daniel W; Zhang, Zhen; Snyder, Michael

    2016-08-01

    Ovarian cancer is the deadliest gynecologic malignancy in the United States with most patients diagnosed in the advanced stage of the disease. Platinum-based antineoplastic therapeutics is indispensable to treating advanced ovarian serous carcinoma. However, patients have heterogeneous responses to platinum drugs, and it is difficult to predict these interindividual differences before administering medication. In this study, we investigated the tumor proteomic profiles and clinical characteristics of 130 ovarian serous carcinoma patients analyzed by the Clinical Proteomic Tumor Analysis Consortium (CPTAC), predicted the platinum drug response using supervised machine learning methods, and evaluated our prediction models through leave-one-out cross-validation. Our data-driven feature selection approach indicated that tumor proteomics profiles contain information for predicting binarized platinum response (P drug responses as well as provided insights into the biological processes influencing the efficacy of platinum-based therapeutics. Our analytical approach is also extensible to predicting response to other antineoplastic agents or treatment modalities for both ovarian and other cancers. PMID:27312948

  6. Molecular markers predicting radiotherapy response: Report and recommendations from an International Atomic Energy Agency technical meeting

    International Nuclear Information System (INIS)

    Purpose: There is increasing interest in radiogenomics and the characterization of molecular profiles that predict normal tissue and tumor radioresponse. A meeting in Amsterdam was organized by the International Atomic Energy Agency to discuss this topic on an international basis. Methods and Materials: This report is not completely exhaustive, but highlights some of the ongoing studies and new initiatives being carried out worldwide in the banking of tumor and normal tissue samples underpinning the development of molecular marker profiles for predicting patient response to radiotherapy. It is generally considered that these profiles will more accurately define individual or group radiosensitivities compared with the nondefinitive findings from the previous era of cellular-based techniques. However, so far there are only a few robust reports of molecular markers predicting normal tissue or tumor response. Results: Many centers in different countries have initiated tissue and tumor banks to store samples from clinical trials for future molecular profiling analysis, to identify profiles that predict for radiotherapy response. The European Society for Therapeutic Radiology and Oncology GENEtic pathways for the Prediction of the effects of Irradiation (GENEPI) project, to store, document, and analyze sample characteristics vs. response, is the most comprehensive in this regard. Conclusions: The next 5-10 years are likely to see the results of these and other correlative studies, and promising associations of profiles with response should be validated in larger definitive trials

  7. Predictive value of brain perfusion SPECT for rTMS response in pharmacoresistant depression

    International Nuclear Information System (INIS)

    The aim of this study was to determine the predictive value of whole-brain voxel-based regional cerebral blood flow (rCBF) for repetitive transcranial magnetic stimulation (rTMS) response in patients with pharmacoresistant depression. Thirty-three right-handed patients who met DSM-IV criteria for major depressive disorder (unipolar or bipolar depression) were included before rTMS. rTMS response was defined as at least 50% reduction in the baseline Beck Depression Inventory scores. The predictive value of 99mTc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) for rTMS response was studied before treatment by comparing rTMS responders to non-responders at voxel level using Statistical Parametric Mapping (SPM) (p 0.10). In comparison to responders, non-responders showed significant hypoperfusions (p < 0.001, uncorrected) in the left medial and bilateral superior frontal cortices (BA10), the left uncus/parahippocampal cortex (BA20/BA35) and the right thalamus. The area under the curve for the combination of SPECT clusters to predict rTMS response was 0.89 (p < 0.001). Sensitivity, specificity, positive predictive value and negative predictive value for the combination of clusters were: 94, 73, 81 and 92%, respectively. This study shows that, in pharmacoresistant depression, pretreatment rCBF of specific brain regions is a strong predictor for response to rTMS in patients with homogeneous demographic/clinical features. (orig.)

  8. Controllability modulates the neural response to predictable but not unpredictable threat in humans.

    Science.gov (United States)

    Wood, Kimberly H; Wheelock, Muriah D; Shumen, Joshua R; Bowen, Kenton H; Ver Hoef, Lawrence W; Knight, David C

    2015-10-01

    Stress resilience is mediated, in part, by our ability to predict and control threats within our environment. Therefore, determining the neural mechanisms that regulate the emotional response to predictable and controllable threats may provide important new insight into the processes that mediate resilience to emotional dysfunction and guide the future development of interventions for anxiety disorders. To better understand the effect of predictability and controllability on threat-related brain activity in humans, two groups of healthy volunteers participated in a yoked Pavlovian fear conditioning study during functional magnetic resonance imaging (fMRI). Threat predictability was manipulated by presenting an aversive unconditioned stimulus (UCS) that was either preceded by a conditioned stimulus (i.e., predictable) or by presenting the UCS alone (i.e., unpredictable). Similar to animal model research that has employed yoked fear conditioning procedures, one group (controllable condition; CC), but not the other group (uncontrollable condition; UC) was able to terminate the UCS. The fMRI signal response within the dorsolateral prefrontal cortex (PFC), dorsomedial PFC, ventromedial PFC, and posterior cingulate was diminished during predictable compared to unpredictable threat (i.e., UCS). In addition, threat-related activity within the ventromedial PFC and bilateral hippocampus was diminished only to threats that were both predictable and controllable. These findings provide insight into how threat predictability and controllability affects the activity of brain regions (i.e., ventromedial PFC and hippocampus) involved in emotion regulation, and may have important implications for better understanding neural processes that mediate emotional resilience to stress.

  9. Resting lateralized activity predicts the cortical response and appraisal of emotions: an fNIRS study.

    Science.gov (United States)

    Balconi, Michela; Grippa, Elisabetta; Vanutelli, Maria Elide

    2015-12-01

    This study explored the effect of lateralized left-right resting brain activity on prefrontal cortical responsiveness to emotional cues and on the explicit appraisal (stimulus evaluation) of emotions based on their valence. Indeed subjective responses to different emotional stimuli should be predicted by brain resting activity and should be lateralized and valence-related (positive vs negative valence). A hemodynamic measure was considered (functional near-infrared spectroscopy). Indeed hemodynamic resting activity and brain response to emotional cues were registered when subjects (N = 19) viewed emotional positive vs negative stimuli (IAPS). Lateralized index response during resting state, LI (lateralized index) during emotional processing and self-assessment manikin rating were considered. Regression analysis showed the significant predictive effect of resting activity (more left or right lateralized) on both brain response and appraisal of emotional cues based on stimuli valence. Moreover, significant effects were found as a function of valence (more right response to negative stimuli; more left response to positive stimuli) during emotion processing. Therefore, resting state may be considered a predictive marker of the successive cortical responsiveness to emotions. The significance of resting condition for emotional behavior was discussed. PMID:25862673

  10. Response to induction chemotherapy as predictive marker of tumor response to radiotherapy and survival in oral cavity cancer

    Directory of Open Access Journals (Sweden)

    Surendra Kumar Saini

    2015-01-01

    Full Text Available Background: Trials have shown some statistically nonsignificant survival advantage of taxane, platin and 5-FU (TPF induction chemotherapy before definitive chemoradiation. We tried to find the role of induction chemotherapy in the prediction of tumor response to radiotherapy and survival in the treatment of oral cavity cancers. Patients and Methods: Patients of stage III and IV (M0 unresectable oral cavity squamous cell carcinoma were assigned to receive two cycles of TPF. On the basis of response to chemotherapy, two groups were made. Those who had partial or more than partial response and another group who had stable disease or disease progression during chemotherapy. Concurrent chemoradiotherapy was given to all patients after induction chemotherapy. Results: A total of 128 patients who received TPF, 29 (22.6% had complete response, 57 (44.5% had partial response, 38 (29.7% had stable disease and 4 (3.1% had progressive disease. Definitive chemoradiotherapy lead to complete response in 48 (55.8% patients who had partial or more than partial response (total 86 to chemotherapy and 10 (23.8% patients among those who had stable disease or disease progression during chemotherapy (total 42. This difference in response is statistically significant (P = 0.001. Three years survival was significantly better after treatment in patients who responded more than partial (hazard ratio 0.463, 95% confidence interval 0.2789-0.7689, with an estimated 3-year survival of 35% in patients in group 1 and 14% in group 2. Conclusion: Response to induction chemotherapy can be a predictive marker for response to subsequent chemoradiotherapy and survival, with acceptable toxicities.

  11. Predicting survey responses: how and why semantics shape survey statistics on organizational behaviour.

    Directory of Open Access Journals (Sweden)

    Jan Ketil Arnulf

    Full Text Available Some disciplines in the social sciences rely heavily on collecting survey responses to detect empirical relationships among variables. We explored whether these relationships were a priori predictable from the semantic properties of the survey items, using language processing algorithms which are now available as new research methods. Language processing algorithms were used to calculate the semantic similarity among all items in state-of-the-art surveys from Organisational Behaviour research. These surveys covered areas such as transformational leadership, work motivation and work outcomes. This information was used to explain and predict the response patterns from real subjects. Semantic algorithms explained 60-86% of the variance in the response patterns and allowed remarkably precise prediction of survey responses from humans, except in a personality test. Even the relationships between independent and their purported dependent variables were accurately predicted. This raises concern about the empirical nature of data collected through some surveys if results are already given a priori through the way subjects are being asked. Survey response patterns seem heavily determined by semantics. Language algorithms may suggest these prior to administering a survey. This study suggests that semantic algorithms are becoming new tools for the social sciences, opening perspectives on survey responses that prevalent psychometric theory cannot explain.

  12. Predicting survey responses: how and why semantics shape survey statistics on organizational behaviour.

    Science.gov (United States)

    Arnulf, Jan Ketil; Larsen, Kai Rune; Martinsen, Øyvind Lund; Bong, Chih How

    2014-01-01

    Some disciplines in the social sciences rely heavily on collecting survey responses to detect empirical relationships among variables. We explored whether these relationships were a priori predictable from the semantic properties of the survey items, using language processing algorithms which are now available as new research methods. Language processing algorithms were used to calculate the semantic similarity among all items in state-of-the-art surveys from Organisational Behaviour research. These surveys covered areas such as transformational leadership, work motivation and work outcomes. This information was used to explain and predict the response patterns from real subjects. Semantic algorithms explained 60-86% of the variance in the response patterns and allowed remarkably precise prediction of survey responses from humans, except in a personality test. Even the relationships between independent and their purported dependent variables were accurately predicted. This raises concern about the empirical nature of data collected through some surveys if results are already given a priori through the way subjects are being asked. Survey response patterns seem heavily determined by semantics. Language algorithms may suggest these prior to administering a survey. This study suggests that semantic algorithms are becoming new tools for the social sciences, opening perspectives on survey responses that prevalent psychometric theory cannot explain. PMID:25184672

  13. Predicting survey responses: how and why semantics shape survey statistics on organizational behaviour.

    Science.gov (United States)

    Arnulf, Jan Ketil; Larsen, Kai Rune; Martinsen, Øyvind Lund; Bong, Chih How

    2014-01-01

    Some disciplines in the social sciences rely heavily on collecting survey responses to detect empirical relationships among variables. We explored whether these relationships were a priori predictable from the semantic properties of the survey items, using language processing algorithms which are now available as new research methods. Language processing algorithms were used to calculate the semantic similarity among all items in state-of-the-art surveys from Organisational Behaviour research. These surveys covered areas such as transformational leadership, work motivation and work outcomes. This information was used to explain and predict the response patterns from real subjects. Semantic algorithms explained 60-86% of the variance in the response patterns and allowed remarkably precise prediction of survey responses from humans, except in a personality test. Even the relationships between independent and their purported dependent variables were accurately predicted. This raises concern about the empirical nature of data collected through some surveys if results are already given a priori through the way subjects are being asked. Survey response patterns seem heavily determined by semantics. Language algorithms may suggest these prior to administering a survey. This study suggests that semantic algorithms are becoming new tools for the social sciences, opening perspectives on survey responses that prevalent psychometric theory cannot explain.

  14. Hazards Response of Energetic Materials - Initiation Mechanisms, Experimental Characterization, and Development of Predictive Capability

    Energy Technology Data Exchange (ETDEWEB)

    Maienschein, J; Nichols III, A; Reaugh, J; McClelland, M; Hsu, P C

    2005-04-15

    We present our approach to develop a predictive capability for hazards -- thermal and non-shock impact -- response of energetic material systems based on: (A) identification of relevant processes; (B) characterization of the relevant properties; (C) application of property data to predictive models; and (D) application of the models into predictive simulation. This paper focuses on the first two elements above, while a companion paper by Nichols et al focuses on the final two elements. We outline the underlying mechanisms of hazards response and their interactions, and present our experimental work to characterize the necessary material parameters, including thermal ignition, thermal and mechanical properties, fracture/fragmentation behavior, deflagration rates, and the effect of material damage. We also describe our validation test, the Scaled Thermal Explosion Experiment. Finally, we integrate the entire collection of data into a qualitative understanding that is useful until such time as the predictive models become available.

  15. Predictions of Unbalanced Response of Turbo Compressor Equipped with Active Magnetic Bearings through System Identification

    Energy Technology Data Exchange (ETDEWEB)

    Baek, SeongKi; NOh, Myounggyu; Park, Young Woo [Chungnam National Univ., Daejeon (Korea, Republic of); Lee, Kiwook; Lee, Nam Soo; Jeog, Jinhee [LG Electronics, Gumi (Korea, Republic of)

    2016-01-15

    Since vibrations in rotating machinery is a direct cause of performance degradation and failures, it is very important to predict the level of vibrations as well as have a method to lower the vibrations to an acceptable level. However, the changes in balancing during installation and the vibrational modes of the support structure are difficult to predict. This paper presents a method for predicting the unbalanced response of a turbo-compressor supported by active magnetic bearings (AMBs). Transfer functions of the rotor are obtained through system identification using AMBs. These transfer functions contain not only the dynamics of the rotor but also the vibrational modes of the support structure. Using these transfer functions, the unbalanced response is calculated and compared with the run-up data obtained from a compressor prototype. The predictions revealed the effects of the support structure, validating the efficacy of the method.

  16. Use of molecular markers for predicting therapy response in cancer patients.

    LENUS (Irish Health Repository)

    Duffy, Michael J

    2012-02-01

    Predictive markers are factors that are associated with upfront response or resistance to a particular therapy. Predictive markers are important in oncology as tumors of the same tissue of origin vary widely in their response to most available systemic therapies. Currently recommended oncological predictive markers include both estrogen and progesterone receptors for identifying patients with breast cancers likely to benefit from hormone therapy, HER-2 for the identification of breast cancer patients likely to benefit from trastuzumab, specific K-RAS mutations for the identification of patients with advanced colorectal cancer unlikely to benefit from either cetuximab or panitumumab and specific EGFR mutations for selecting patients with advanced non-small-cell lung cancer for treatment with tyrosine kinase inhibitors such as gefitinib and erlotinib. The availability of predictive markers should increase drug efficacy and decrease toxicity, thus leading to a more personalized approach to cancer treatment.

  17. Predicting Climate Change using Response Theory: Global Averages and Spatial Patterns

    CERN Document Server

    Lucarini, Valerio; Ragone, Francesco

    2015-01-01

    The provision of accurate methods for predicting the climate response to anthropogenic and natural forcings is a key contemporary scientific challenge. Using a simplified and efficient open-source general circulation model of the atmosphere featuring O($10^5$) degrees of freedom, we show how it is possible to approach such a problem using nonequilibrium statistical mechanics. Response theory allows one to practically compute the time-dependent measure supported on the pullback attractor of the climate system, whose dynamics is non-autonomous as a result of time-dependent forcings. We propose a simple yet efficient method for predicting - at any lead time and in an ensemble sense - the change in climate properties resulting from increase in the concentration of CO$_2$ using test perturbation model runs. We assess strengths and limitations of the response theory in predicting the changes in the globally averaged values of surface temperature and of the yearly total precipitation, as well as their spatial patter...

  18. Personalized in vitro cancer models to predict therapeutic response: Challenges and a framework for improvement.

    Science.gov (United States)

    Morgan, Molly M; Johnson, Brian P; Livingston, Megan K; Schuler, Linda A; Alarid, Elaine T; Sung, Kyung E; Beebe, David J

    2016-09-01

    Personalized cancer therapy focuses on characterizing the relevant phenotypes of the patient, as well as the patient's tumor, to predict the most effective cancer therapy. Historically, these methods have not proven predictive in regards to predicting therapeutic response. Emerging culture platforms are designed to better recapitulate the in vivo environment, thus, there is renewed interest in integrating patient samples into in vitro cancer models to assess therapeutic response. Successful examples of translating in vitro response to clinical relevance are limited due to issues with patient sample acquisition, variability and culture. We will review traditional and emerging in vitro models for personalized medicine, focusing on the technologies, microenvironmental components, and readouts utilized. We will then offer our perspective on how to apply a framework derived from toxicology and ecology towards designing improved personalized in vitro models of cancer. The framework serves as a tool for identifying optimal readouts and culture conditions, thus maximizing the information gained from each patient sample.

  19. Systemic Inflammation Response Syndrome Score Predicts the Mortality in Multiple Trauma Patients

    OpenAIRE

    Baek, Jong Hyun; Kim, Myeong Su; Lee, Jung Cheul; Lee, Jang Hoon

    2014-01-01

    Background Numerous statistical models have been developed to accurately predict outcomes in multiple trauma patients. However, such trauma scoring systems reflect the patient’s physiological condition, which can only be determined to a limited extent, and are difficult to use when performing a rapid initial assessment. We studied the predictive ability of the systemic inflammatory response syndrome (SIRS) score compared to other scoring systems. Methods We retrospectively reviewed 229 patien...

  20. Response prediction for large scale model structure under forced vibration test

    International Nuclear Information System (INIS)

    This paper presents the analytical prediction for the responses of the forced vibration test on a quarter-scale containment model structure built at Hualien, Taiwan. The prediction is performed blindly by using the computer program HASSI-8 which is developed for solving the soil-structure interaction problem using the method of hybrid modeling. The results obtained show very good correlation with the field test results

  1. Predicting Anticancer Drug Responses Using a Dual-Layer Integrated Cell Line-Drug Network Model.

    Directory of Open Access Journals (Sweden)

    Naiqian Zhang

    Full Text Available The ability to predict the response of a cancer patient to a therapeutic agent is a major goal in modern oncology that should ultimately lead to personalized treatment. Existing approaches to predicting drug sensitivity rely primarily on profiling of cancer cell line panels that have been treated with different drugs and selecting genomic or functional genomic features to regress or classify the drug response. Here, we propose a dual-layer integrated cell line-drug network model, which uses both cell line similarity network (CSN data and drug similarity network (DSN data to predict the drug response of a given cell line using a weighted model. Using the Cancer Cell Line Encyclopedia (CCLE and Cancer Genome Project (CGP studies as benchmark datasets, our single-layer model with CSN or DSN and only a single parameter achieved a prediction performance comparable to the previously generated elastic net model. When using the dual-layer model integrating both CSN and DSN, our predicted response reached a 0.6 Pearson correlation coefficient with observed responses for most drugs, which is significantly better than the previous results using the elastic net model. We have also applied the dual-layer cell line-drug integrated network model to fill in the missing drug response values in the CGP dataset. Even though the dual-layer integrated cell line-drug network model does not specifically model mutation information, it correctly predicted that BRAF mutant cell lines would be more sensitive than BRAF wild-type cell lines to three MEK1/2 inhibitors tested.

  2. Predictive value of brain perfusion SPECT for ketamine response in hyperalgesic fibromyalgia

    International Nuclear Information System (INIS)

    Ketamine has been used successfully in various proportions of fibromyalgia (FM) patients. However, the response to this specific treatment remains largely unpredictable. We evaluated brain SPECT perfusion before treatment with ketamine, using voxel-based analysis. The objective was to determine the predictive value of brain SPECT for ketamine response. Seventeen women with FM (48 ± 11 years; ACR criteria) were enrolled in the study. Brain SPECT was performed before any change was made in therapy in the pain care unit. We considered that a patient was a good responder to ketamine if the VAS score for pain decreased by at least 50% after treatment. A voxel-by-voxel group analysis was performed using SPM2, in comparison to a group of ten healthy women matched for age. The VAS score for pain was 81.8 ± 4.2 before ketamine and 31.8 ± 27.1 after ketamine. Eleven patients were considered ''good responders'' to ketamine. Responder and non-responder subgroups were similar in terms of pain intensity before ketamine. In comparison to responding patients and healthy subjects, non-responding patients exhibited a significant reduction in bilateral perfusion of the medial frontal gyrus. This cluster of hypoperfusion was highly predictive of non-response to ketamine (positive predictive value 100%, negative predictive value 91%). Brain perfusion SPECT may predict response to ketamine in hyperalgesic FM patients. (orig.)

  3. Predictive value of brain perfusion SPECT for ketamine response in hyperalgesic fibromyalgia

    Energy Technology Data Exchange (ETDEWEB)

    Guedj, Eric; Cammilleri, Serge; Colavolpe, Cecile; Taieb, David; Laforte, Catherine de; Mundler, Olivier [Centre Hospitalo-Universitaire de la Timone, Service Central de Biophysique et de Medecine Nucleaire, Assistance Publique des Hopitaux de Marseille, Marseille Cedex 5 (France); Niboyet, Jean [Clinique La Phoceanne, Unite d' Etude et de Traitement de la Douleur, Marseille (France)

    2007-08-15

    Ketamine has been used successfully in various proportions of fibromyalgia (FM) patients. However, the response to this specific treatment remains largely unpredictable. We evaluated brain SPECT perfusion before treatment with ketamine, using voxel-based analysis. The objective was to determine the predictive value of brain SPECT for ketamine response. Seventeen women with FM (48 {+-} 11 years; ACR criteria) were enrolled in the study. Brain SPECT was performed before any change was made in therapy in the pain care unit. We considered that a patient was a good responder to ketamine if the VAS score for pain decreased by at least 50% after treatment. A voxel-by-voxel group analysis was performed using SPM2, in comparison to a group of ten healthy women matched for age. The VAS score for pain was 81.8 {+-} 4.2 before ketamine and 31.8 {+-} 27.1 after ketamine. Eleven patients were considered ''good responders'' to ketamine. Responder and non-responder subgroups were similar in terms of pain intensity before ketamine. In comparison to responding patients and healthy subjects, non-responding patients exhibited a significant reduction in bilateral perfusion of the medial frontal gyrus. This cluster of hypoperfusion was highly predictive of non-response to ketamine (positive predictive value 100%, negative predictive value 91%). Brain perfusion SPECT may predict response to ketamine in hyperalgesic FM patients. (orig.)

  4. Comparison of total body water estimates from O-18 and bioelectrical response prediction equations

    Science.gov (United States)

    Barrows, Linda H.; Inners, L. Daniel; Stricklin, Marcella D.; Klein, Peter D.; Wong, William W.; Siconolfi, Steven F.

    1993-01-01

    Identification of an indirect, rapid means to measure total body water (TBW) during space flight may aid in quantifying hydration status and assist in countermeasure development. Bioelectrical response testing and hydrostatic weighing were performed on 27 subjects who ingested O-18, a naturally occurring isotope of oxygen, to measure true TBW. TBW estimates from three bioelectrical response prediction equations and fat-free mass (FFM) were compared to TBW measured from O-18. A repeated measures MANOVA with post-hoc Dunnett's Test indicated a significant (p less than 0.05) difference between TBW estimates from two of the three bioelectrical response prediction equations and O-18. TBW estimates from FFM and the Kushner & Schoeller (1986) equation yielded results that were similar to those given by O-18. Strong correlations existed between each prediction method and O-18; however, standard errors, identified through regression analyses, were higher for the bioelectrical response prediction equations compared to those derived from FFM. These findings suggest (1) the Kushner & Schoeller (1986) equation may provide a valid measure of TBW, (2) other TBW prediction equations need to be identified that have variability similar to that of FFM, and (3) bioelectrical estimates of TBW may prove valuable in quantifying hydration status during space flight.

  5. On the best learning algorithm for web services response time prediction

    DEFF Research Database (Denmark)

    Madsen, Henrik; Albu, Razvan-Daniel; Popentiu-Vladicescu, Florin

    2013-01-01

    In this article we will examine the effect of different learning algorithms, while training the MLP (Multilayer Perceptron) with the intention of predicting web services response time. Web services do not necessitate a user interface. This may seem contradictory to most people's concept of what...... an application is. A Web service is better imagined as an application "segment," or better as a program enabler. Performance is an important quality aspect of Web services because of their distributed nature. Predicting the response of web services during their operation is very important....

  6. Predicting failure response of spot welded joints using recent extensions to the Gurson model

    DEFF Research Database (Denmark)

    Nielsen, Kim Lau

    2010-01-01

    The plug failure modes of resistance spot welded shear-lab and cross-tension test specimens are studied, using recent extensions to the Gurson model. A comparison of the predicted mechanical response is presented when using either: (i) the Gurson-Tvergaard-Needleman model (GTN-model), (ii......) the shear-modified GTN-model by Nahshon and Hutchinson that also describes damage development at low triaxiality (NH-model) or (iii) the Gologanu-Leblond-Devaux model (GLD-model) accounting for non-spherical void growth. The failure responses predicted by the various models are discussed in relation...

  7. Pareto Optimization Identifies Diverse Set of Phosphorylation Signatures Predicting Response to Treatment with Dasatinib.

    Science.gov (United States)

    Klammer, Martin; Dybowski, J Nikolaj; Hoffmann, Daniel; Schaab, Christoph

    2015-01-01

    Multivariate biomarkers that can predict the effectiveness of targeted therapy in individual patients are highly desired. Previous biomarker discovery studies have largely focused on the identification of single biomarker signatures, aimed at maximizing prediction accuracy. Here, we present a different approach that identifies multiple biomarkers by simultaneously optimizing their predictive power, number of features, and proximity to the drug target in a protein-protein interaction network. To this end, we incorporated NSGA-II, a fast and elitist multi-objective optimization algorithm that is based on the principle of Pareto optimality, into the biomarker discovery workflow. The method was applied to quantitative phosphoproteome data of 19 non-small cell lung cancer (NSCLC) cell lines from a previous biomarker study. The algorithm successfully identified a total of 77 candidate biomarker signatures predicting response to treatment with dasatinib. Through filtering and similarity clustering, this set was trimmed to four final biomarker signatures, which then were validated on an independent set of breast cancer cell lines. All four candidates reached the same good prediction accuracy (83%) as the originally published biomarker. Although the newly discovered signatures were diverse in their composition and in their size, the central protein of the originally published signature - integrin β4 (ITGB4) - was also present in all four Pareto signatures, confirming its pivotal role in predicting dasatinib response in NSCLC cell lines. In summary, the method presented here allows for a robust and simultaneous identification of multiple multivariate biomarkers that are optimized for prediction performance, size, and relevance.

  8. DISIS: prediction of drug response through an iterative sure independence screening.

    Directory of Open Access Journals (Sweden)

    Yun Fang

    Full Text Available Prediction of drug response based on genomic alterations is an important task in the research of personalized medicine. Current elastic net model utilized a sure independence screening to select relevant genomic features with drug response, but it may neglect the combination effect of some marginally weak features. In this work, we applied an iterative sure independence screening scheme to select drug response relevant features from the Cancer Cell Line Encyclopedia (CCLE dataset. For each drug in CCLE, we selected up to 40 features including gene expressions, mutation and copy number alterations of cancer-related genes, and some of them are significantly strong features but showing weak marginal correlation with drug response vector. Lasso regression based on the selected features showed that our prediction accuracies are higher than those by elastic net regression for most drugs.

  9. High-throughput screening using patient-derived tumor xenografts to predict clinical trial drug response.

    Science.gov (United States)

    Gao, Hui; Korn, Joshua M; Ferretti, Stéphane; Monahan, John E; Wang, Youzhen; Singh, Mallika; Zhang, Chao; Schnell, Christian; Yang, Guizhi; Zhang, Yun; Balbin, O Alejandro; Barbe, Stéphanie; Cai, Hongbo; Casey, Fergal; Chatterjee, Susmita; Chiang, Derek Y; Chuai, Shannon; Cogan, Shawn M; Collins, Scott D; Dammassa, Ernesta; Ebel, Nicolas; Embry, Millicent; Green, John; Kauffmann, Audrey; Kowal, Colleen; Leary, Rebecca J; Lehar, Joseph; Liang, Ying; Loo, Alice; Lorenzana, Edward; Robert McDonald, E; McLaughlin, Margaret E; Merkin, Jason; Meyer, Ronald; Naylor, Tara L; Patawaran, Montesa; Reddy, Anupama; Röelli, Claudia; Ruddy, David A; Salangsang, Fernando; Santacroce, Francesca; Singh, Angad P; Tang, Yan; Tinetto, Walter; Tobler, Sonja; Velazquez, Roberto; Venkatesan, Kavitha; Von Arx, Fabian; Wang, Hui Qin; Wang, Zongyao; Wiesmann, Marion; Wyss, Daniel; Xu, Fiona; Bitter, Hans; Atadja, Peter; Lees, Emma; Hofmann, Francesco; Li, En; Keen, Nicholas; Cozens, Robert; Jensen, Michael Rugaard; Pryer, Nancy K; Williams, Juliet A; Sellers, William R

    2015-11-01

    Profiling candidate therapeutics with limited cancer models during preclinical development hinders predictions of clinical efficacy and identifying factors that underlie heterogeneous patient responses for patient-selection strategies. We established ∼1,000 patient-derived tumor xenograft models (PDXs) with a diverse set of driver mutations. With these PDXs, we performed in vivo compound screens using a 1 × 1 × 1 experimental design (PDX clinical trial or PCT) to assess the population responses to 62 treatments across six indications. We demonstrate both the reproducibility and the clinical translatability of this approach by identifying associations between a genotype and drug response, and established mechanisms of resistance. In addition, our results suggest that PCTs may represent a more accurate approach than cell line models for assessing the clinical potential of some therapeutic modalities. We therefore propose that this experimental paradigm could potentially improve preclinical evaluation of treatment modalities and enhance our ability to predict clinical trial responses.

  10. Pathological predictive factors for tumor response in locally advanced breast carcinomas treated with anthracyclin-based neoadjuvant chemotherapy

    Directory of Open Access Journals (Sweden)

    Trupti Patel

    2013-01-01

    Conclusion: Pathological parameters like type of tumor, presence of LVE and tumor necrosis in the core biopsy can predict the response to NACT in routine stain. Tumor necrosis and type of breast carcinoma are predictive parameters for tumor responsiveness to NACT. LVE was reliable in predicting axillary lymph node metastasis.

  11. Biological markers as predictive factors of response to neoadjuvant taxanes and anthracycline chemotherapy in breast carcinoma

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bo; YANG De-qi; XIE Fei

    2008-01-01

    Background Neoadjuvant chemotherapy provides an excellent model for evaluation of potential predictive factors.The objective of this study was to evaluate the predictive value of different biological factors in breast cancer patients treated with neoadjuvant taxane and anthracycline chemotherapy.Methods One hundred and thirty-five patients treated with 4 cycles of neoadjuvant taxanes and anthracycline were included in this retrospective study.Using pretreatment biopsy materials,immunohistochemical studies were performed for estrogen receptor(ER),progesterone receptor(PgR),HER-2,Ki-67 and p53 protein expression.The associations among biological markers and clinical and pathological complete response (pCR)were analyzed.Results The overall clinical response was 86%,including 33%clinical complete response(cCR)and 53%clinical partial response.The pCR was iust 17%.In the univariate analysis,only HER-2 overexpression was predictive of cCR to neoadjuvant chemotherapy(P=0.018).No significant associations between other biological factors and cCR were found.Absence of ER,PgR expression and overexpression of HER-2 were predictive of the pCR(P=0.002,0.001,0.01,respectively).Ki-67 and p53 failed to show an association with pCR.In multivariate analysis,overexpression of HER-2remained as an independent variable in predicting the cCR(P=0.021).However,negative ER was the only parameter that maintained statistical significance in predicting the pCR(P=0.001).Conclusions Patients with overexoression of HER-2 and negative hormonal receptor status are much more likely to respond to neoadjuvant taxane and anthracycline chemotherapy than those with the opposite characte ristics.These factors could serve as predictive markers for this regimen.

  12. Cortisol and Inflammatory Biomarkers Predict Poor Treatment Response in First Episode Psychosis

    OpenAIRE

    Mondelli, Valeria; Ciufolini, Simone; Belvederi Murri, Martino; Bonaccorso, Stefania; Di Forti, Marta; Giordano, Annalisa; Marques, Tiago R; Zunszain, Patricia A.; Morgan, Craig; MURRAY, Robin M.; Pariante, Carmine M.; Dazzan, Paola

    2015-01-01

    BACKGROUND: Cortisol and inflammatory markers have been increasingly reported as abnormal at psychosis onset. The main aim of our study was to investigate the ability of these biomarkers to predict treatment response at 12 weeks follow-up in first episode psychosis.METHODS: In a longitudinal study, we collected saliva and blood samples in 68 first episode psychosis patients (and 57 controls) at baseline and assessed response to clinician-led antipsychotic treatment after 12 weeks. Moreover, w...

  13. Early Prediction and Evaluation of Breast Cancer Response to Neoadjuvant Chemotherapy Using Quantitative DCE-MRI

    OpenAIRE

    Alina Tudorica; Oh, Karen Y.; Stephen Y-C Chui; Nicole Roy; Troxell, Megan L.; Arpana Naik; Kathleen A Kemmer; Yiyi Chen; Megan L Holtorf; Aneela Afzal; Charles S Springer Jr.; Xin Li; Wei Huang

    2016-01-01

    The purpose is to compare quantitative dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) metrics with imaging tumor size for early prediction of breast cancer response to neoadjuvant chemotherapy (NACT) and evaluation of residual cancer burden (RCB). Twenty-eight patients with 29 primary breast tumors underwent DCE-MRI exams before, after one cycle of, at midpoint of, and after NACT. MRI tumor size in the longest diameter (LD) was measured according to the RECIST (Response Eval...

  14. Predicting Response to Hormonal Therapy and Survival in Men with Hormone Sensitive Metastatic Prostate Cancer

    OpenAIRE

    Grivas, Petros D; Robins, Diane M.; Hussain, Maha

    2012-01-01

    Androgen deprivation is the cornerstone of the management of metastatic prostate cancer. Despite several decades of clinical experience with this therapy there are no standard predictive biomarkers for response. Although several candidate genetic, hormonal, inflammatory, biochemical, metabolic biomarkers have been suggested as potential predictors of response and outcome, none has been prospectively validated nor has proven clinical utility to date. There is significant heterogeneity in the d...

  15. Predicting a human gut microbiota’s response to diet in gnotobiotic mice

    OpenAIRE

    Faith, Jeremiah J; Nathan P McNulty; Rey, Federico E.; Jeffrey I Gordon

    2011-01-01

    The inter-relationships between our diets and the structure and operations of our gut microbial communities are poorly understood. A model community of ten sequenced human gut bacteria was introduced into gnotobiotic mice, and changes in species abundance and microbial gene expression were measured in response to randomized perturbations of four defined ingredients in the host diet. From the responses, we developed a statistical model that predicted over 60% of the variation in species abunda...

  16. Texture analysis on MR images helps predicting non-response to NAC in breast cancer.

    OpenAIRE

    Michoux, N.; Van den Broeck, S; Lacoste, L; Fellah, L.; Galant, Christine; Berlière, M.; Leconte, I

    2015-01-01

    Background To assess the performance of a predictive model of non-response to neoadjuvant chemotherapy (NAC) in patients with breast cancer based on texture, kinetic, and BI-RADS parameters measured from dynamic MRI. Methods Sixty-nine patients with invasive ductal carcinoma of the breast who underwent pre-treatment MRI were studied. Morphological parameters and biological markers were measured. Pathological complete response was defined as the absence of invasive and in situ cancer in breast...

  17. Depression and anxiety predict sex-specific cortisol responses to interpersonal stress.

    Science.gov (United States)

    Powers, Sally I; Laurent, Heidemarie K; Gunlicks-Stoessel, Meredith; Balaban, Susan; Bent, Eileen

    2016-07-01

    Clinical theories posit interpersonal stress as an important factor in the emergence and exacerbation of depression and anxiety, while neuroendocrine research confirms the association of these syndromes with dysregulation in a major stress response system, the hypothalamic-pituitary-adrenal (HPA) axis. However, the proposal that depression and anxiety symptoms and diagnoses are associated with problematic HPA responses to close relationship stress has not been directly tested. We examined 196 heterosexual dating couples' depression and anxiety symptoms and diagnoses, assessed with questionnaires and diagnostic interviews, in relation to cortisol responses to discussion of an unresolved relationship conflict. Participants provided seven salivary samples in anticipation of and directly following the discussion, and throughout an hour-long recovery period, which were assayed for cortisol. Multilevel models of the HPA response predicted by symptoms or diagnoses showed that women's depressive symptoms predicted attenuated cortisol levels, with a flatter response curve. In contrast, men's depression symptoms and women's anxiety symptoms and diagnoses predicted higher cortisol levels. These findings highlight the importance of examining sex differences in responses to interpersonal stressors for understanding HPA dysregulation in internalizing psychopathology. PMID:27107208

  18. Single-subject prediction of response inhibition behavior by event-related potentials.

    Science.gov (United States)

    Stock, Ann-Kathrin; Popescu, Florin; Neuhaus, Andres H; Beste, Christian

    2016-03-01

    Much research has been devoted to investigating response inhibition and the neuronal processes constituting this essential cognitive faculty. However, the nexus between cognitive subprocesses, behavior, and electrophysiological processes remains associative in nature. We therefore investigated whether neurophysiological correlates of inhibition subprocesses merely correlate with behavioral performance or actually provide information expedient to the prediction of behavior on a single-subject level. Tackling this question, we used different data-driven classification approaches in a sample of n = 262 healthy young subjects who completed a standard Go/Nogo task while an EEG was recorded. On the basis of median-split response inhibition performance, subjects were classified as "accurate/slow" and "less accurate/fast." Even though these behavioral group differences were associated with significant amplitude variations in classical electrophysiological correlates of response inhibition (i.e., N2 and P3), they were not predictive for group membership on a single-subject level. Instead, amplitude differences in the Go-P2 originating in the precuneus (BA7) were shown to predict group membership on a single-subject level with up to 64% accuracy. These findings strongly suggest that the behavioral outcome of response inhibition greatly depends on the amount of cognitive resources allocated to early stages of stimulus-response activation during responding. This suggests that research should focus more on early processing steps during responding when trying to understand the origin of interindividual differences in response inhibition processes. PMID:26683075

  19. Response to induction chemotherapy as predictive marker of tumor response to radiotherapy and survival in oral cavity cancer

    OpenAIRE

    Surendra Kumar Saini; Shelly Srivastava; Shanbhu Nath Prasad

    2015-01-01

    Background: Trials have shown some statistically nonsignificant survival advantage of taxane, platin and 5-FU (TPF) induction chemotherapy before definitive chemoradiation. We tried to find the role of induction chemotherapy in the prediction of tumor response to radiotherapy and survival in the treatment of oral cavity cancers. Patients and Methods: Patients of stage III and IV (M0) unresectable oral cavity squamous cell carcinoma were assigned to receive two cycles of TPF. On the basis of r...

  20. Nomogram for predicting pathologically complete response after neoadjuvant chemoradiotherapy for oesophageal cancer

    International Nuclear Information System (INIS)

    Background: A pathologically complete response (pCR) to neoadjuvant chemoradiotherapy (nCRT) is seen in 30% of the patients with oesophageal cancer. The aim is to identify patient and tumour characteristics associated with a pCR and to develop a nomogram for the prediction of pCR. Patients and methods: Patients who underwent nCRT followed by surgery were identified and response to nCRT was assessed according to a modified Mandard classification in the resection specimen. A model was developed with age, gender, histology and location of the tumour, differentiation grade, alcohol use, smoking, percentage weight loss, Charlson Comorbidity Index (CCI), cT-stage and cN-stage as potential predictors for pCR. Probability of pCR was studied via logistic regression. Performance of the prediction nomogram was quantified using the concordance statistic (c-statistic) and corrected for optimism. Results: A total of 381 patients were included. After surgery, 27.6% of the tumours showed a pCR. Female sex, squamous cell histology, poor differentiation grade, and low cT-stage were predictive for a pCR with a c-statistic of 0.64 (corrected for optimism). Conclusion: A nomogram for the prediction of pathologically complete response after neoadjuvant chemoradiotherapy was developed, with a reasonable predictive power. This nomogram needs external validation before it can be used for individualised clinical decision-making

  1. Predicting the response of localised oesophageal cancer to neo-adjuvant chemoradiation

    Directory of Open Access Journals (Sweden)

    Reynolds John

    2007-08-01

    Full Text Available Abstract Background A complete pathological response to neo-adjuvant chemo-radiation for oesophageal cancer is associated with favourable survival. However, such a benefit is seen in the minority. If one could identify, at diagnosis, those patients who were unlikely to respond unnecessary toxicity could be avoided and alternative treatment can be considered. The aim of this review was to highlight predictive markers currently assessed and evaluate their clinical utility. Methods A systematic search of Pubmed and Google Scholar was performed using the following keywords; "neo-adjuvant", "oesophageal", "trimodality", "chemotherapy", "radiotherapy", "chemoradiation" and "predict". The original manuscripts were sourced for further articles of relevance. Results Conventional indices including tumour stage and grade seem unable to predict histological response. Immuno-histochemical markers have been extensively studied, but none has made its way into routine clinical practice. Global gene expression from fresh pre-treatment tissue using cDNA microarray has only recently been assessed, but shows considerable promise. Molecular imaging using FDG-PET seems to be able to predict response after neo-adjuvant chemoradiation has finished, but there is a paucity of data when such imaging is performed earlier. Conclusion Currently there are no clinically useful predictors of response based on standard pathological assessment and immunohistochemistry. Genomics, proteomics and molecular imaging may hold promise.

  2. Dynamic preload indicators fail to predict fluid responsiveness in open-chest conditions

    NARCIS (Netherlands)

    de Waal, Eric E. C.; Rex, Steffen; Kruitwagen, Cas L. J. J.; Kalkman, Cor J.; Buhre, Wolfgang F.

    2009-01-01

    Objective: Dynamic preload indicators like pulse pressure variation (PPV) and stroke volume variation (SVV) are increasingly being used for optimizing cardiac preload since they have been demonstrated to predict fluid responsiveness in a variety of perioperative settings. However, in open-chest cond

  3. A noise level prediction method based on electro-mechanical frequency response function for capacitors.

    Directory of Open Access Journals (Sweden)

    Lingyu Zhu

    Full Text Available The capacitors in high-voltage direct-current (HVDC converter stations radiate a lot of audible noise which can reach higher than 100 dB. The existing noise level prediction methods are not satisfying enough. In this paper, a new noise level prediction method is proposed based on a frequency response function considering both electrical and mechanical characteristics of capacitors. The electro-mechanical frequency response function (EMFRF is defined as the frequency domain quotient of the vibration response and the squared capacitor voltage, and it is obtained from impulse current experiment. Under given excitations, the vibration response of the capacitor tank is the product of EMFRF and the square of the given capacitor voltage in frequency domain, and the radiated audible noise is calculated by structure acoustic coupling formulas. The noise level under the same excitations is also measured in laboratory, and the results are compared with the prediction. The comparison proves that the noise prediction method is effective.

  4. Predicting People's Environmental Behaviour: Theory of Planned Behaviour and Model of Responsible Environmental Behaviour

    Science.gov (United States)

    Chao, Yu-Long

    2012-01-01

    Using different measures of self-reported and other-reported environmental behaviour (EB), two important theoretical models explaining EB--Hines, Hungerford and Tomera's model of responsible environmental behaviour (REB) and Ajzen's theory of planned behaviour (TPB)--were compared regarding the fit between model and data, predictive ability,…

  5. Pre- and post-radiotherapy MRI results as a predictive model for response in laryngeal carcinoma

    NARCIS (Netherlands)

    Ljumanovic, Redina; Langendijk, Johannes A.; Hoekstra, Otto S.; Knol, Dirk L.; Leemans, C. Rene; Castelijns, Jonas A.

    2008-01-01

    The purpose was to determine if pre-radiotherapy (RT) and/or post-radiotherapy magnetic resonance (MR) imaging can predict response in patients with laryngeal carcinoma treated with RT. Pre- and post-RT MR examinations of 80 patients were retrospectively reviewed and associated with regard to local

  6. Prediction of resistance development against drug combinations by collateral responses to component drugs

    DEFF Research Database (Denmark)

    Munck, Christian; Gumpert, Heidi; Nilsson Wallin, Annika;

    2014-01-01

    to do so. Thus, predictive models are needed to rationally design resistance-limiting therapeutic regimens. Using adaptive evolution, we studied the resistance response of the common pathogen Escherichia coli to 5 different single antibiotics and all 10 different antibiotic drug pairs. By analyzing...

  7. PREDICTING RICE YIELD RESPONSE TO MIDSEASON NITROGEN WITH PLANT AREA MEASURMENTS

    Science.gov (United States)

    A simple method is needed to aid farmers with midseason N decisions in dry-seeded, delayed flood rice (Oryza sativa L.). This study was conducted to develop thresholds using visual and digital image measurements for predicting rice yield response to N topdressing. 'Francis' and 'Cheniere' (cv) ric...

  8. Noninvasively derived stroke volume variation by finger volume clamping can reliably predict fluid responsiveness

    NARCIS (Netherlands)

    Vos, Jaap Jan; Poterman, Marieke; Struys, Michel; Scheeren, Thomas; Kalmar, A.F.

    2013-01-01

    Background and Goal of Study:  Dynamic preload variables derived from the arterial pressure waveform have been shown to accurately predict fluid responsiveness in mechanically ventilated patients. One of these variables, stroke volume variation (SVV), can also be obtained noninvasively by the finger

  9. Predictive Power of the Baseline QRS Complex Duration for Clinical Response to Cardiac Resynchronisation Therapy

    Directory of Open Access Journals (Sweden)

    Ali Kazemisaeid

    2011-02-01

    Full Text Available Background: Determination of predictors of response to cardiac resynchronisation therapy (CRT in patients with moderate to severe heart failure accompanied by a ventricular dyssynchrony can play a major role in improving candidate selection for CRT.Objectives: We evaluated whether the baseline QRS duration could be used to discriminate responders from non-responders to CRT.Methods: Eighty three consecutive patients with moderate to severe heart failure and with successful implantation of a CRT device at our centre were included in the study. QRS durations were measured on 12-lead surface electrocardiogram before and 6 months after implantation of the CRT device, using the widest QRS complex in leads II, V1 and V6. Clinical response to CRT was defined as an improvement of ≥1 grade in NYHA class.Results: Optimal cut-off value to discriminate baseline QRS duration for predicting clinical response to CRT was identified at 152 ms, yielding a sensitivity of 73.3%, a specificity of 56.5% as well as positive and negative predictive values of 81.5% and 44.8%, respectively. The discriminatory pow- er of the baseline QRS duration for response to CRT assessed by the ROC curve was 0.6402 (95% CI: 0.4976 – 0.7829. Baseline QRS duration ≥ 152 ms could effectively predict clinical response to CRT after adjusting for covariates (OR = 3.743, p = 0.017.Conclusion: Baseline QRS duration can effectively predict clinical response to CRT and optimal cut-off value to discriminate baseline QRS duration for response to CRT is 152 ms.

  10. Modeling transducer impulse responses for predicting calibrated pressure pulses with the ultrasound simulation program Field II

    DEFF Research Database (Denmark)

    Bæk, David; Jensen, Jørgen Arendt; Willatzen, Morten

    2010-01-01

    FIELD II is a simulation software capable of predicting the field pressure in front of transducers having any complicated geometry. A calibrated prediction with this program is, however, dependent on an exact voltage-to-surface acceleration impulse response of the transducer. Such impulse response...... is not calculated by FIELD II. This work investigates the usability of combining a one-dimensional multilayer transducer modeling principle with the FIELD II software. Multilayer here refers to a transducer composed of several material layers. Measurements of pressure and current from Pz27 piezoceramic disks...... as well as pressure and intensity measurements in front of a 128 element commercial convex medical transducer are compared to the simulations. Results show that the models can predict the pressure from the piezoceramic disks with a root mean square (rms) error of 11.2% to 36.2% with a 2 dB amplitude...

  11. Research on Responsivity of Microbolometer in Food Temperature Prediction by System-level Collaborative Simulation Method

    Directory of Open Access Journals (Sweden)

    Chao Chen

    2015-09-01

    Full Text Available In this study, an 320×240 are fabricated according to the design to verify the system-level co-simulation results. Due to the complexity of microbolometer in food temperature prediction heat-transfer structure, thermoelectric characteristics could’t be simulated in the same design platform with the design of its Read-Out Integrated Circuit (ROIC which is monolithically integrated with the heat-transfer structure. The purpose of coordinated simulation is to find out a coordinated analysis method between microbolometer in food temperature prediction and its Read-Out Integrated Circuit (ROIC. Input and output characteristics of microbolometer in food temperature prediction was obtained. Responsivity of the heat-transfer model is analyzed based on the results of system-level collaborative simulation. Test values of responsivity matched the known design results of simulation well.

  12. The value of metabolic imaging to predict tumour response after chemoradiation in locally advanced rectal cancer

    Directory of Open Access Journals (Sweden)

    Gómez-Río Manuel

    2010-12-01

    Full Text Available Abstract Background We aim to investigate the possibility of using 18F-positron emission tomography/computer tomography (PET-CT to predict the histopathologic response in locally advanced rectal cancer (LARC treated with preoperative chemoradiation (CRT. Methods The study included 50 patients with LARC treated with preoperative CRT. All patients were evaluated by PET-CT before and after CRT, and results were compared to histopathologic response quantified by tumour regression grade (patients with TRG 1-2 being defined as responders and patients with grade 3-5 as non-responders. Furthermore, the predictive value of metabolic imaging for pathologic complete response (ypCR was investigated. Results Responders and non-responders showed statistically significant differences according to Mandard's criteria for maximum standardized uptake value (SUVmax before and after CRT with a specificity of 76,6% and a positive predictive value of 66,7%. Furthermore, SUVmax values after CRT were able to differentiate patients with ypCR with a sensitivity of 63% and a specificity of 74,4% (positive predictive value 41,2% and negative predictive value 87,9%; This rather low sensitivity and specificity determined that PET-CT was only able to distinguish 7 cases of ypCR from a total of 11 patients. Conclusions We conclude that 18-F PET-CT performed five to seven weeks after the end of CRT can visualise functional tumour response in LARC. In contrast, metabolic imaging with 18-F PET-CT is not able to predict patients with ypCR accurately.

  13. Predictive value of brain perfusion SPECT for rTMS response in pharmacoresistant depression

    Energy Technology Data Exchange (ETDEWEB)

    Richieri, Raphaelle; Lancon, Christophe [Sainte-Marguerite University Hospital, Department of Psychiatry, Marseille (France); La Timone University, EA 3279 - Self-perceived Health Assessment Research Unit, School of Medicine, Marseille (France); Boyer, Laurent [La Timone University, EA 3279 - Self-perceived Health Assessment Research Unit, School of Medicine, Marseille (France); La Timone University Hospital, Assistance Publique - Hopitaux de Marseille, Department of Public Health, Marseille (France); Farisse, Jean [Sainte-Marguerite University Hospital, Department of Psychiatry, Marseille (France); Colavolpe, Cecile; Mundler, Olivier [La Timone University Hospital, Assistance Publique - Hopitaux de Marseille, Service Central de Biophysique et Medecine Nucleaire, Marseille (France); Universite de la Mediterranee, Centre Europeen de Recherche en Imagerie Medicale (CERIMED), Marseille (France); Guedj, Eric [La Timone University Hospital, Assistance Publique - Hopitaux de Marseille, Service Central de Biophysique et Medecine Nucleaire, Marseille (France); Universite de la Mediterranee, Centre Europeen de Recherche en Imagerie Medicale (CERIMED), Marseille (France); Hopital de la Timone, Service Central de Biophysique et de Medecine Nucleaire, Marseille Cedex 5 (France)

    2011-09-15

    The aim of this study was to determine the predictive value of whole-brain voxel-based regional cerebral blood flow (rCBF) for repetitive transcranial magnetic stimulation (rTMS) response in patients with pharmacoresistant depression. Thirty-three right-handed patients who met DSM-IV criteria for major depressive disorder (unipolar or bipolar depression) were included before rTMS. rTMS response was defined as at least 50% reduction in the baseline Beck Depression Inventory scores. The predictive value of {sup 99m}Tc-ethyl cysteinate dimer (ECD) single photon emission computed tomography (SPECT) for rTMS response was studied before treatment by comparing rTMS responders to non-responders at voxel level using Statistical Parametric Mapping (SPM) (p < 0.001, uncorrected). Of the patients, 18 (54.5%) were responders to rTMS and 15 were non-responders (45.5%). There were no statistically significant differences in demographic and clinical characteristics (p > 0.10). In comparison to responders, non-responders showed significant hypoperfusions (p < 0.001, uncorrected) in the left medial and bilateral superior frontal cortices (BA10), the left uncus/parahippocampal cortex (BA20/BA35) and the right thalamus. The area under the curve for the combination of SPECT clusters to predict rTMS response was 0.89 (p < 0.001). Sensitivity, specificity, positive predictive value and negative predictive value for the combination of clusters were: 94, 73, 81 and 92%, respectively. This study shows that, in pharmacoresistant depression, pretreatment rCBF of specific brain regions is a strong predictor for response to rTMS in patients with homogeneous demographic/clinical features. (orig.)

  14. Prediction of pore-water pressure response to rainfall using support vector regression

    Science.gov (United States)

    Babangida, Nuraddeen Muhammad; Mustafa, Muhammad Raza Ul; Yusuf, Khamaruzaman Wan; Isa, Mohamed Hasnain

    2016-05-01

    Nonlinear complex behavior of pore-water pressure responses to rainfall was modelled using support vector regression (SVR). Pore-water pressure can rise to disturbing levels that may result in slope failure during or after rainfall. Traditionally, monitoring slope pore-water pressure responses to rainfall is tedious and expensive, in that the slope must be instrumented with necessary monitors. Data on rainfall and corresponding responses of pore-water pressure were collected from such a monitoring program at a slope site in Malaysia and used to develop SVR models to predict pore-water pressure fluctuations. Three models, based on their different input configurations, were developed. SVR optimum meta-parameters were obtained using k-fold cross validation and a grid search. Model type 3 was adjudged the best among the models and was used to predict three other points on the slope. For each point, lag intervals of 30 min, 1 h and 2 h were used to make the predictions. The SVR model predictions were compared with predictions made by an artificial neural network model; overall, the SVR model showed slightly better results. Uncertainty quantification analysis was also performed for further model assessment. The uncertainty components were found to be low and tolerable, with d-factor of 0.14 and 74 % of observed data falling within the 95 % confidence bound. The study demonstrated that the SVR model is effective in providing an accurate and quick means of obtaining pore-water pressure response, which may be vital in systems where response information is urgently needed.

  15. Synthesising empirical results to improve predictions of post-wildfire runoff and erosion response

    Science.gov (United States)

    Shakesby, Richard A.; Moody, John A.; Martin, Deborah A.; Robichaud, Peter R.

    2016-01-01

    Advances in research into wildfire impacts on runoff and erosion have demonstrated increasing complexity of controlling factors and responses, which, combined with changing fire frequency, present challenges for modellers. We convened a conference attended by experts and practitioners in post-wildfire impacts, meteorology and related research, including modelling, to focus on priority research issues. The aim was to improve our understanding of controls and responses and the predictive capabilities of models. This conference led to the eight selected papers in this special issue. They address aspects of the distinctiveness in the controls and responses among wildfire regions, spatiotemporal rainfall variability, infiltration, runoff connectivity, debris flow formation and modelling applications. Here we summarise key findings from these papers and evaluate their contribution to improving understanding and prediction of post-wildfire runoff and erosion under changes in climate, human intervention and population pressure on wildfire-prone areas.

  16. PREDICTION OF SITE RESPONSE SPECTRUM UNDER EARTHQUAKE VIBRATION USING AN OPTIMIZED DEVELOPED ARTIFICIAL NEURAL NETWORK MODEL

    Directory of Open Access Journals (Sweden)

    Reza Esmaeilabadi

    2016-06-01

    Full Text Available Site response spectrum is one of the key factors to determine the maximum acceleration and displacement, as well as structure behavior analysis during earthquake vibrations. The main objective of this paper is to develop an optimized model based on artificial neural network (ANN using five different training algorithms to predict nonlinear site response spectrum subjected to Silakhor earthquake vibrations is. The model output was tested for a specified area in west of Iran. The performance and quality of optimized model under all training algorithms have been examined by various statistical, analytical and graph analyses criteria as well as a comparison with numerical methods. The observed adaptabilities in results indicate a feasible and satisfactory engineering alternative method for predicting the analysis of nonlinear site response.

  17. Snoring Sounds Predict Obstruction Sites and Surgical Response in Patients with Obstructive Sleep Apnea Hypopnea Syndrome.

    Science.gov (United States)

    Lee, Li-Ang; Lo, Yu-Lun; Yu, Jen-Fang; Lee, Gui-She; Ni, Yung-Lun; Chen, Ning-Hung; Fang, Tuan-Jen; Huang, Chung-Guei; Cheng, Wen-Nuan; Li, Hsueh-Yu

    2016-01-01

    Snoring sounds generated by different vibrators of the upper airway may be useful indicators of obstruction sites in patients with obstructive sleep apnea hypopnea syndrome (OSAHS). This study aimed to investigate associations between snoring sounds, obstruction sites, and surgical responses (≥50% reduction in the apnea-hypopnea index [AHI] and Hz; odds ratio [OR], 1.25, 95% confidence interval [CI] 1.05-1.49) and body mass index (OR, 1.48, 95% CI 1.02-2.15) after logistic regression analysis. Tonsil obstruction was significantly, inversely correlated with mean snoring sound intensity (301-850 Hz; OR, 0.84, 95% CI 0.74-0.96). Moreover, baseline tonsil obstruction detected by either DISE or mean snoring sound intensity (301-850 Hz), and AHI could significantly predict the surgical response. Our findings suggest that snoring sound detection may be helpful in determining obstruction sites and predict surgical responses. PMID:27471038

  18. RBFNN Model for Predicting Nonlinear Response of Uniformly Loaded Paddle Cantilever

    Directory of Open Access Journals (Sweden)

    Abdullah H. Abdullah

    2009-01-01

    Full Text Available The Radial basis Function neural network (RBFNN model has been developed for the prediction of nonlinear response for paddle Cantilever with built-in edges and different sizes, thickness and uniform loads. Learning data was performed by using a nonlinear finite element program, incremental stages of the nonlinear finite element analysis were generated by using 25 schemes of built paddle Cantilevers with different thickness and uniform distributed loads. The neural network model has 5 input nodes representing the uniform distributed load and paddle size, length, width and thickness, eight nodes at hidden layer and one output node representing the max. deflection response (1500×1 represent the deflection response of load. Regression analysis between finite element results and values predicted by the neural network model shows the least error.

  19. Spatially pooled contrast responses predict neural and perceptual similarity of naturalistic image categories.

    Directory of Open Access Journals (Sweden)

    Iris I A Groen

    Full Text Available The visual world is complex and continuously changing. Yet, our brain transforms patterns of light falling on our retina into a coherent percept within a few hundred milliseconds. Possibly, low-level neural responses already carry substantial information to facilitate rapid characterization of the visual input. Here, we computationally estimated low-level contrast responses to computer-generated naturalistic images, and tested whether spatial pooling of these responses could predict image similarity at the neural and behavioral level. Using EEG, we show that statistics derived from pooled responses explain a large amount of variance between single-image evoked potentials (ERPs in individual subjects. Dissimilarity analysis on multi-electrode ERPs demonstrated that large differences between images in pooled response statistics are predictive of more dissimilar patterns of evoked activity, whereas images with little difference in statistics give rise to highly similar evoked activity patterns. In a separate behavioral experiment, images with large differences in statistics were judged as different categories, whereas images with little differences were confused. These findings suggest that statistics derived from low-level contrast responses can be extracted in early visual processing and can be relevant for rapid judgment of visual similarity. We compared our results with two other, well- known contrast statistics: Fourier power spectra and higher-order properties of contrast distributions (skewness and kurtosis. Interestingly, whereas these statistics allow for accurate image categorization, they do not predict ERP response patterns or behavioral categorization confusions. These converging computational, neural and behavioral results suggest that statistics of pooled contrast responses contain information that corresponds with perceived visual similarity in a rapid, low-level categorization task.

  20. Amygdala response to explicit sad face stimuli at baseline predicts antidepressant treatment response to scopolamine in major depressive disorder.

    Science.gov (United States)

    Szczepanik, Joanna; Nugent, Allison C; Drevets, Wayne C; Khanna, Ashish; Zarate, Carlos A; Furey, Maura L

    2016-08-30

    The muscarinic antagonist scopolamine produces rapid antidepressant effects in individuals with major depressive disorder (MDD). In healthy subjects, manipulation of acetyl-cholinergic transmission modulates attention in a stimulus-dependent manner. This study tested the hypothesis that baseline amygdalar activity in response to emotional stimuli correlates with antidepressant treatment response to scopolamine and could thus potentially predict treatment outcome. MDD patients and healthy controls performed an attention shifting task involving emotional faces while undergoing functional magnetic resonance imaging (fMRI). We found that blood oxygenation level dependent (BOLD) signal in the amygdala acquired while MDD patients processed sad face stimuli correlated positively with antidepressant response to scopolamine. Amygdalar response to sad faces in MDD patients who did not respond to scopolamine did not differ from that of healthy controls. This suggests that the pre-treatment task elicited amygdalar activity that may constitute a biomarker of antidepressant treatment response to scopolamine. Furthermore, in MDD patients who responded to scopolamine, we observed a post-scopolamine stimulus processing shift towards a pattern demonstrated by healthy controls, indicating a change in stimulus-dependent neural response potentially driven by attenuated cholinergic activity in the amygdala. PMID:27366831

  1. Seismic response prediction for cabinets of nuclear power plants by using impact hammer test

    International Nuclear Information System (INIS)

    An effective method to predict the seismic response of electrical cabinets of nuclear power plants is developed. This method consists of three steps: (1) identification of the earthquake-equivalent force based on the idealized lumped-mass system of the cabinet, (2) identification of the state-space equation (SSE) model of the system using input-output measurements from impact hammer tests, and (3) seismic response prediction by calculating the output of the identified SSE model under the identified earthquake-equivalent force. A three-dimensional plate model of cabinet structures is presented for the numerical verification of the proposed method. Experimental validation of the proposed method is carried out on a three-story frame which represents the structure of a cabinet. The SSE model of the frame is accurately identified by impact hammer tests with high fitness values over 85% of the actual frame characteristics. Shaking table tests are performed using El Centro, Kobe, and Northridge earthquakes as input motions and the acceleration responses are measured. The responses of the model under the three earthquakes are predicted and then compared with the measured responses. The predicted and measured responses agree well with each other with fitness values of 65-75%. The proposed method is more advantageous over other methods that are based on finite element (FE) model updating since it is free from FE modeling errors. It will be especially effective for cabinet structures in nuclear power plants where conducting shaking table tests may not be feasible. Limitations of the proposed method are also discussed.

  2. Predictive Factors of Tumor Response After Neoadjuvant Chemoradiation for Locally Advanced Rectal Cancer

    International Nuclear Information System (INIS)

    Purpose: Neoadjuvant chemoradiation followed by surgery is the standard of care for locally advanced rectal cancer. The aim of this study was to correlate tumor response to survival and to identify predictive factors for tumor response after chemoradiation. Methods and Materials: From 1998 to 2008, 168 patients with histologically proven locally advanced adenocarcinoma treated by preoperative chemoradiation before total mesorectal excision were retrospectively studied. They received a radiation dose of 45 Gy with a concomitant 5-fluorouracil (5-FU)-based chemotherapy. Analysis of tumor response was based on lowering of the T stage between pretreatment endorectal ultrasound and pathologic specimens. Overall and progression-free survival rates were correlated with tumor response. Tumor response was analyzed with predictive factors. Results: The median follow-up was 34 months. Five-year disease-free survival and overall survival rates were, of 44.4% and 74.5% in the whole population, 83.4% and 83.4%, respectively, in patients with pathological complete response, 38.6% and 71.9%, respectively, in patients with tumor downstaging, and 29.1and 58.9% respectively, in patients with absence of response. A pretreatment carcinoembryonic antigen (CEA) level of <5 ng/ml was significantly independently associated with pathologic complete tumor response (p = 0.019). Pretreatment small tumor size (p = 0.04), pretreatment CEA level of <5 ng/ml (p = 0.008), and chemotherapy with capecitabine (vs. 5-FU) (p = 0.04) were significantly associated with tumor downstaging. Conclusions: Downstaging and complete response after CRT improved progression-free survival and overall survival of locally advanced rectal adenocarcinoma. In multivariate analysis, a pretreatment CEA level of <5 ng/ml was associated with complete tumor response. Thus, small tumor size, a pretreatment CEA level of < 5ng/ml, and use of capecitabine were associated with tumor downstaging.

  3. Predicting decadal trends and transient responses of radiocarbon storage and fluxes in a temperate forest soil

    Directory of Open Access Journals (Sweden)

    C. A. Sierra

    2012-08-01

    Full Text Available Representing the response of soil carbon dynamics to global environmental change requires the incorporation of multiple tools in the development of predictive models. An important tool to construct and test models is the incorporation of bomb radiocarbon in soil organic matter during the past decades. In this manuscript, we combined radiocarbon data and a previously developed empirical model to explore decade-scale soil carbon dynamics in a temperate forest ecosystem at the Harvard Forest, Massachusetts, USA. We evaluated the contribution of different soil C fractions to both total soil CO2 efflux and microbially respired C. We tested the performance of the model based on measurable soil organic matter fractions against a decade of radiocarbon measurements. The model was then challenged with radiocarbon measurements from a warming and N addition experiment to test multiple hypotheses about the different response of soil C fractions to the experimental manipulations. Our results showed that the empirical model satisfactorily predicts the trends of radiocarbon in litter, density fractions, and respired CO2 observed over a decade in the soils not subjected to manipulation. However, the model, modified with prescribed relationships for temperature and decomposition rates, predicted most but not all the observations from the field experiment where soil temperatures and nitrogen levels were increased, suggesting that a larger degree of complexity and mechanistic relations need to be added to the model to predict short-term responses and transient dynamics.

  4. From neural responses to population behavior: neural focus group predicts population-level media effects.

    Science.gov (United States)

    Falk, Emily B; Berkman, Elliot T; Lieberman, Matthew D

    2012-05-01

    Can neural responses of a small group of individuals predict the behavior of large-scale populations? In this investigation, brain activations were recorded while smokers viewed three different television campaigns promoting the National Cancer Institute's telephone hotline to help smokers quit (1-800-QUIT-NOW). The smokers also provided self-report predictions of the campaigns' relative effectiveness. Population measures of the success of each campaign were computed by comparing call volume to 1-800-QUIT-NOW in the month before and the month after the launch of each campaign. This approach allowed us to directly compare the predictive value of self-reports with neural predictors of message effectiveness. Neural activity in a medial prefrontal region of interest, previously associated with individual behavior change, predicted the population response, whereas self-report judgments did not. This finding suggests a novel way of connecting neural signals to population responses that has not been previously demonstrated and provides information that may be difficult to obtain otherwise. PMID:22510393

  5. Predicting decadal trends and transient responses of radiocarbon storage and fluxes in a temperate forest soil

    Directory of Open Access Journals (Sweden)

    C. A. Sierra

    2012-02-01

    Full Text Available Representing the response of soil carbon dynamics to global environmental change requires the incorporation of multiple tools in the development of predictive models. An important tool to construct and test models is the incorporation of bomb radiocarbon in soil organic matter during the past decades. In this manuscript, we combined radiocarbon data and a previously developed empirical model to explore decade-scale soil carbon dynamics in a temperate forest ecosystem at the Harvard Forest, Massachusetts, USA. We evaluated the contribution of different soil C fractions to both total soil CO2 efflux and microbially-respired C. We tested the performance of the model based on measurable soil organic matter fractions against a decade of radiocarbon measurements. The model was then challenged with radiocarbon measurements from a warming and N addition experiment to test multiple hypotheses about the different response of soil C fractions to the experimental manipulations. Our results showed that the empirical model satisfactorily predicts the trends of radiocarbon in litter, density fractions, and respired CO2 observed over a decade in the soils not subjected to manipulation. However, the model, modified with prescribed relationships for temperature and decomposition rates, predicted most but not all the observations from the field experiment where soil temperatures and nitrogen levels were increased, suggesting that a larger degree of complexity and mechanistic relations need to be added to the model to predict short-term responses and transient dynamics.

  6. Lateralization for speech predicts therapeutic response to cognitive behavioral therapy for depression.

    Science.gov (United States)

    Kishon, Ronit; Abraham, Karen; Alschuler, Daniel M; Keilp, John G; Stewart, Jonathan W; McGrath, Patrick J; Bruder, Gerard E

    2015-08-30

    A prior study (Bruder, G.E., Stewart, J.W., Mercier, M.A., Agosti, V., Leite, P., Donovan, S., Quitkin, F.M., 1997. Outcome of cognitive-behavioral therapy for depression: relation of hemispheric dominance for verbal processing. Journal of Abnormal Psychology 106, 138-144.) found left hemisphere advantage for verbal dichotic listening was predictive of clinical response to cognitive behavioral therapy (CBT) for depression. This study aimed to confirm this finding and to examine the value of neuropsychological tests, which have shown promise for predicting antidepressant response. Twenty depressed patients who subsequently completed 14 weeks of CBT and 74 healthy adults were tested on a Dichotic Fused Words Test (DFWT). Patients were also tested on the National Adult Reading Test to estimate IQ, and word fluency, choice RT, and Stroop neuropsychological tests. Left hemisphere advantage on the DFWT was more than twice as large in CBT responders as in non-responders, and was associated with improvement in depression following treatment. There was no difference between responders and non-responders on neuropsychological tests. The results support the hypothesis that the ability of individuals with strong left hemisphere dominance to recruit frontal and temporal cortical regions involved in verbal dichotic listening predicts CBT response. The large effect size, sensitivity and specificity of DFWT predictions suggest the potential value of this brief and inexpensive test as an indicator of whether a patient will benefit from CBT for depression.

  7. Predicting community responses to perturbations in the face of imperfect knowledge and network complexity

    Science.gov (United States)

    Novak, M.; Wootton, J.T.; Doak, D.F.; Emmerson, M.; Estes, J.A.; Tinker, M.T.

    2011-01-01

    How best to predict the effects of perturbations to ecological communities has been a long-standing goal for both applied and basic ecology. This quest has recently been revived by new empirical data, new analysis methods, and increased computing speed, with the promise that ecologically important insights may be obtainable from a limited knowledge of community interactions. We use empirically based and simulated networks of varying size and connectance to assess two limitations to predicting perturbation responses in multispecies communities: (1) the inaccuracy by which species interaction strengths are empirically quantified and (2) the indeterminacy of species responses due to indirect effects associated with network size and structure. We find that even modest levels of species richness and connectance (??25 pairwise interactions) impose high requirements for interaction strength estimates because system indeterminacy rapidly overwhelms predictive insights. Nevertheless, even poorly estimated interaction strengths provide greater average predictive certainty than an approach that uses only the sign of each interaction. Our simulations provide guidance in dealing with the trade-offs involved in maximizing the utility of network approaches for predicting dynamics in multispecies communities. ?? 2011 by the Ecological Society of America.

  8. Serum alpha-fetoprotein response can predict prognosis in hepatocellular carcinoma patients undergoing radiofrequency ablation therapy

    International Nuclear Information System (INIS)

    Aims: To evaluate the clinical inference of serum alpha-fetoprotein (AFP) response in hepatocellular carcinoma (HCC) patients undergoing percutaneous radiofrequency ablation (RFA). Materials and methods: Three hundred and thirteen previously untreated HCC patients were enrolled in the study. The optimal AFP response was defined as >20% decrease from baseline after 1 month of RFA for those with a baseline AFP level of ≥100 ng/ml. The impact of AFP response on prognosis was analysed and prognostic factors were assessed. Results: After a median follow-up of 26.7 ± 19.1 months, 49 patients died and 264 patients were alive. The cumulative 5 year survival rates were 75.3 and 57.4% in patients with an initial AFP of 1.1 (p = 0.009), non-optimal AFP response (p = 0.023), and creatinine >1.5 mg/dl (p = 0.021) were independent risk factors predictive of poor overall survival. Besides, the cumulative 5 year recurrence rates were 83.4 and 100% in optimal and non-optimal AFP responders, respectively (p 5/mm3 (p = 0.048), tumour size >2 cm (p = 0.027), and non-optimal AFP response (p < 0.001) were independent risk factors associated with tumour recurrence after RFA. Conclusions: Serum AFP response may be a useful marker for predicting prognosis in HCC patients undergoing RFA.

  9. Gene Co-Expression Analysis Predicts Genetic Variants Associated with Drug Responsiveness in Lung Cancer.

    Science.gov (United States)

    Shroff, Sanaya; Zhang, Jie; Huang, Kun

    2016-01-01

    Responsiveness to drugs is an important concern in designing personalized treatment for cancer patients. Currently genetic markers are often used to guide targeted therapy. However, deeper understanding of the molecular basis for drug responses and discovery of new predictive biomarkers for drug sensitivity are much needed. In this paper, we present a workflow for identifying condition-specific gene co-expression networks associated with responses to the tyrosine kinase inhibitor, Erlotinib, in lung adenocarcinoma cell lines using data from the Cancer Cell Line Encyclopedia by combining network mining and statistical analysis. Particularly, we have identified multiple gene modules specifically co-expressed in the drug responsive cell lines but not in the unresponsive group. Interestingly, most of these modules are enriched on specific cytobands, suggesting potential copy number variation events on these loci. Our results therefore imply that there are multiple genetic loci with copy number variations associated with the Erlotinib responses. The existence of CNVs in these loci is also confirmed in lung cancer tissue samples using the TCGA data. Since these structural variations are inferred from functional genomics data, these CNVs are functional variations. These results suggest the condition specific gene co- expression network mining approach is an effective approach in predicting candidate biomarkers for drug responses. PMID:27570645

  10. Use of Germline Polymorphisms in Predicting Concurrent Chemoradiotherapy Response in Esophageal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Pei-Chun [Department of Statistics and Informatics Science, Providence University, Taiwan (China); Chen, Yen-Ching [Institute of Epidemiology Preventive Medicine, College of Public Health, National Taiwan University, Taiwan (China); Research Center for Gene, Environment, and Human Health, College of Public Health, National Taiwan University, Taiwan (China); Department of Public Health, Institute of Epidemiology, National Taiwan University, Taiwan (China); Lai, Liang-Chuan [Graduate Institute of Physiology, National Taiwan University, Taiwan (China); Tsai, Mong-Hsun [Institute of Biotechnology, National Taiwan University, Taiwan (China); Chen, Shin-Kuang [National Clinical Trial and Research Center, National Taiwan University Hospital, Taiwan (China); Yang, Pei-Wen; Lee, Yung-Chie [Department of Surgery, National Taiwan University Hospital, Taiwan (China); Hsiao, Chuhsing K. [Research Center for Gene, Environment, and Human Health, College of Public Health, National Taiwan University, Taiwan (China); Department of Public Health, Institute of Epidemiology, National Taiwan University, Taiwan (China); Bioinformatics and Biostatistics Core, Research Center for Medical Excellence, National Taiwan University, Taiwan (China); Lee, Jang-Ming, E-mail: jangming@ntuh.gov.tw [Department of Surgery, National Taiwan University Hospital, Taiwan (China); Chuang, Eric Y., E-mail: chuangey@ntu.edu.tw [National Clinical Trial and Research Center, National Taiwan University Hospital, Taiwan (China); Bioinformatics and Biostatistics Core, Research Center for Medical Excellence, National Taiwan University, Taiwan (China); Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taiwan (China)

    2012-04-01

    Purpose: To identify germline polymorphisms to predict concurrent chemoradiation therapy (CCRT) response in esophageal cancer patients. Materials and Methods: A total of 139 esophageal cancer patients treated with CCRT (cisplatin-based chemotherapy combined with 40 Gy of irradiation) and subsequent esophagectomy were recruited at the National Taiwan University Hospital between 1997 and 2008. After excluding confounding factors (i.e., females and patients aged {>=}70 years), 116 patients were enrolled to identify single nucleotide polymorphisms (SNPs) associated with specific CCRT responses. Genotyping arrays and mass spectrometry were used sequentially to determine germline polymorphisms from blood samples. These polymorphisms remain stable throughout disease progression, unlike somatic mutations from tumor tissues. Two-stage design and additive genetic models were adopted in this study. Results: From the 26 SNPs identified in the first stage, 2 SNPs were found to be significantly associated with CCRT response in the second stage. Single nucleotide polymorphism rs16863886, located between SGPP2 and FARSB on chromosome 2q36.1, was significantly associated with a 3.93-fold increase in pathologic complete response to CCRT (95% confidence interval 1.62-10.30) under additive models. Single nucleotide polymorphism rs4954256, located in ZRANB3 on chromosome 2q21.3, was associated with a 3.93-fold increase in pathologic complete response to CCRT (95% confidence interval 1.57-10.87). The predictive accuracy for CCRT response was 71.59% with these two SNPs combined. Conclusions: This is the first study to identify germline polymorphisms with a high accuracy for predicting CCRT response in the treatment of esophageal cancer.

  11. Early Prediction and Evaluation of Breast Cancer Response to Neoadjuvant Chemotherapy Using Quantitative DCE-MRI.

    Science.gov (United States)

    Tudorica, Alina; Oh, Karen Y; Chui, Stephen Y-C; Roy, Nicole; Troxell, Megan L; Naik, Arpana; Kemmer, Kathleen A; Chen, Yiyi; Holtorf, Megan L; Afzal, Aneela; Springer, Charles S; Li, Xin; Huang, Wei

    2016-02-01

    The purpose is to compare quantitative dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) metrics with imaging tumor size for early prediction of breast cancer response to neoadjuvant chemotherapy (NACT) and evaluation of residual cancer burden (RCB). Twenty-eight patients with 29 primary breast tumors underwent DCE-MRI exams before, after one cycle of, at midpoint of, and after NACT. MRI tumor size in the longest diameter (LD) was measured according to the RECIST (Response Evaluation Criteria In Solid Tumors) guidelines. Pharmacokinetic analyses of DCE-MRI data were performed with the standard Tofts and Shutter-Speed models (TM and SSM). After one NACT cycle the percent changes of DCE-MRI parameters K(trans) (contrast agent plasma/interstitium transfer rate constant), ve (extravascular and extracellular volume fraction), kep (intravasation rate constant), and SSM-unique τi (mean intracellular water lifetime) are good to excellent early predictors of pathologic complete response (pCR) vs. non-pCR, with univariate logistic regression C statistics value in the range of 0.804 to 0.967. ve values after one cycle and at NACT midpoint are also good predictors of response, with C ranging 0.845 to 0.897. However, RECIST LD changes are poor predictors with C = 0.609 and 0.673, respectively. Post-NACT K(trans), τi, and RECIST LD show statistically significant (P < .05) correlations with RCB. The performances of TM and SSM analyses for early prediction of response and RCB evaluation are comparable. In conclusion, quantitative DCE-MRI parameters are superior to imaging tumor size for early prediction of therapy response. Both TM and SSM analyses are effective for therapy response evaluation. However, the τi parameter derived only with SSM analysis allows the unique opportunity to potentially quantify therapy-induced changes in tumor energetic metabolism. PMID:26947876

  12. Early Prediction and Evaluation of Breast Cancer Response to Neoadjuvant Chemotherapy Using Quantitative DCE-MRI

    Directory of Open Access Journals (Sweden)

    Alina Tudorica

    2016-02-01

    Full Text Available The purpose is to compare quantitative dynamic contrast-enhanced (DCE magnetic resonance imaging (MRI metrics with imaging tumor size for early prediction of breast cancer response to neoadjuvant chemotherapy (NACT and evaluation of residual cancer burden (RCB. Twenty-eight patients with 29 primary breast tumors underwent DCE-MRI exams before, after one cycle of, at midpoint of, and after NACT. MRI tumor size in the longest diameter (LD was measured according to the RECIST (Response Evaluation Criteria In Solid Tumors guidelines. Pharmacokinetic analyses of DCE-MRI data were performed with the standard Tofts and Shutter-Speed models (TM and SSM. After one NACT cycle the percent changes of DCE-MRI parameters Ktrans (contrast agent plasma/interstitium transfer rate constant, ve (extravascular and extracellular volume fraction, kep (intravasation rate constant, and SSM-unique τi (mean intracellular water lifetime are good to excellent early predictors of pathologic complete response (pCR vs. non-pCR, with univariate logistic regression C statistics value in the range of 0.804 to 0.967. ve values after one cycle and at NACT midpoint are also good predictors of response, with C ranging 0.845 to 0.897. However, RECIST LD changes are poor predictors with C = 0.609 and 0.673, respectively. Post-NACT Ktrans, τi, and RECIST LD show statistically significant (P < .05 correlations with RCB. The performances of TM and SSM analyses for early prediction of response and RCB evaluation are comparable. In conclusion, quantitative DCE-MRI parameters are superior to imaging tumor size for early prediction of therapy response. Both TM and SSM analyses are effective for therapy response evaluation. However, the τi parameter derived only with SSM analysis allows the unique opportunity to potentially quantify therapy-induced changes in tumor energetic metabolism.

  13. Use of Germline Polymorphisms in Predicting Concurrent Chemoradiotherapy Response in Esophageal Cancer

    International Nuclear Information System (INIS)

    Purpose: To identify germline polymorphisms to predict concurrent chemoradiation therapy (CCRT) response in esophageal cancer patients. Materials and Methods: A total of 139 esophageal cancer patients treated with CCRT (cisplatin-based chemotherapy combined with 40 Gy of irradiation) and subsequent esophagectomy were recruited at the National Taiwan University Hospital between 1997 and 2008. After excluding confounding factors (i.e., females and patients aged ≥70 years), 116 patients were enrolled to identify single nucleotide polymorphisms (SNPs) associated with specific CCRT responses. Genotyping arrays and mass spectrometry were used sequentially to determine germline polymorphisms from blood samples. These polymorphisms remain stable throughout disease progression, unlike somatic mutations from tumor tissues. Two-stage design and additive genetic models were adopted in this study. Results: From the 26 SNPs identified in the first stage, 2 SNPs were found to be significantly associated with CCRT response in the second stage. Single nucleotide polymorphism rs16863886, located between SGPP2 and FARSB on chromosome 2q36.1, was significantly associated with a 3.93-fold increase in pathologic complete response to CCRT (95% confidence interval 1.62–10.30) under additive models. Single nucleotide polymorphism rs4954256, located in ZRANB3 on chromosome 2q21.3, was associated with a 3.93-fold increase in pathologic complete response to CCRT (95% confidence interval 1.57–10.87). The predictive accuracy for CCRT response was 71.59% with these two SNPs combined. Conclusions: This is the first study to identify germline polymorphisms with a high accuracy for predicting CCRT response in the treatment of esophageal cancer.

  14. Lateral prefrontal cortex activity during cognitive control of emotion predicts response to social stress in schizophrenia

    Directory of Open Access Journals (Sweden)

    Laura M. Tully, PhD

    2014-01-01

    Full Text Available LPFC dysfunction is a well-established neural impairment in schizophrenia and is associated with worse symptoms. However, how LPFC activation influences symptoms is unclear. Previous findings in healthy individuals demonstrate that lateral prefrontal cortex (LPFC activation during cognitive control of emotional information predicts mood and behavior in response to interpersonal conflict, thus impairments in these processes may contribute to symptom exacerbation in schizophrenia. We investigated whether schizophrenia participants show LPFC deficits during cognitive control of emotional information, and whether these LPFC deficits prospectively predict changes in mood and symptoms following real-world interpersonal conflict. During fMRI, 23 individuals with schizophrenia or schizoaffective disorder and 24 healthy controls completed the Multi-Source Interference Task superimposed on neutral and negative pictures. Afterwards, schizophrenia participants completed a 21-day online daily-diary in which they rated the extent to which they experienced mood and schizophrenia-spectrum symptoms, as well as the occurrence and response to interpersonal conflict. Schizophrenia participants had lower dorsal LPFC activity (BA9 during cognitive control of task-irrelevant negative emotional information. Within schizophrenia participants, DLPFC activity during cognitive control of emotional information predicted changes in positive and negative mood on days following highly distressing interpersonal conflicts. Results have implications for understanding the specific role of LPFC in response to social stress in schizophrenia, and suggest that treatments targeting LPFC-mediated cognitive control of emotion could promote adaptive response to social stress in schizophrenia.

  15. Lateral prefrontal cortex activity during cognitive control of emotion predicts response to social stress in schizophrenia.

    Science.gov (United States)

    Tully, Laura M; Lincoln, Sarah Hope; Hooker, Christine I

    2014-01-01

    LPFC dysfunction is a well-established neural impairment in schizophrenia and is associated with worse symptoms. However, how LPFC activation influences symptoms is unclear. Previous findings in healthy individuals demonstrate that lateral prefrontal cortex (LPFC) activation during cognitive control of emotional information predicts mood and behavior in response to interpersonal conflict, thus impairments in these processes may contribute to symptom exacerbation in schizophrenia. We investigated whether schizophrenia participants show LPFC deficits during cognitive control of emotional information, and whether these LPFC deficits prospectively predict changes in mood and symptoms following real-world interpersonal conflict. During fMRI, 23 individuals with schizophrenia or schizoaffective disorder and 24 healthy controls completed the Multi-Source Interference Task superimposed on neutral and negative pictures. Afterwards, schizophrenia participants completed a 21-day online daily-diary in which they rated the extent to which they experienced mood and schizophrenia-spectrum symptoms, as well as the occurrence and response to interpersonal conflict. Schizophrenia participants had lower dorsal LPFC activity (BA9) during cognitive control of task-irrelevant negative emotional information. Within schizophrenia participants, DLPFC activity during cognitive control of emotional information predicted changes in positive and negative mood on days following highly distressing interpersonal conflicts. Results have implications for understanding the specific role of LPFC in response to social stress in schizophrenia, and suggest that treatments targeting LPFC-mediated cognitive control of emotion could promote adaptive response to social stress in schizophrenia.

  16. A new ovarian response prediction index (ORPI: implications for individualised controlled ovarian stimulation

    Directory of Open Access Journals (Sweden)

    Oliveira Joao Batista A

    2012-11-01

    Full Text Available Abstract Background The objective was to present a new ovarian response prediction index (ORPI, which was based on anti-Müllerian hormone (AMH levels, antral follicle count (AFC and age, and to verify whether it could be a reliable predictor of the ovarian stimulation response. Methods A total of 101 patients enrolled in the ICSI programme were included. The ORPI values were calculated by multiplying the AMH level (ng/ml by the number of antral follicles (2–9 mm, and the result was divided by the age (years of the patient (ORPI=(AMH x AFC/Patient age. Results The regression analysis demonstrated significant (PP=0.006 and collecting greater than or equal to 4 oocytes (OR: 49.25; PPP Conclusions The ORPI exhibited an excellent ability to predict a low ovarian response and a good ability to predict a collection of greater than or equal to 4 MII oocytes, an excessive ovarian response and the occurrence of pregnancy in infertile women. The ORPI might be used to improve the cost-benefit ratio of ovarian stimulation regimens by guiding the selection of medications and by modulating the doses and regimens according to the actual needs of the patients.

  17. Integrating Transcriptomic and Proteomic Data Using Predictive Regulatory Network Models of Host Response to Pathogens.

    Directory of Open Access Journals (Sweden)

    Deborah Chasman

    2016-07-01

    Full Text Available Mammalian host response to pathogenic infections is controlled by a complex regulatory network connecting regulatory proteins such as transcription factors and signaling proteins to target genes. An important challenge in infectious disease research is to understand molecular similarities and differences in mammalian host response to diverse sets of pathogens. Recently, systems biology studies have produced rich collections of omic profiles measuring host response to infectious agents such as influenza viruses at multiple levels. To gain a comprehensive understanding of the regulatory network driving host response to multiple infectious agents, we integrated host transcriptomes and proteomes using a network-based approach. Our approach combines expression-based regulatory network inference, structured-sparsity based regression, and network information flow to infer putative physical regulatory programs for expression modules. We applied our approach to identify regulatory networks, modules and subnetworks that drive host response to multiple influenza infections. The inferred regulatory network and modules are significantly enriched for known pathways of immune response and implicate apoptosis, splicing, and interferon signaling processes in the differential response of viral infections of different pathogenicities. We used the learned network to prioritize regulators and study virus and time-point specific networks. RNAi-based knockdown of predicted regulators had significant impact on viral replication and include several previously unknown regulators. Taken together, our integrated analysis identified novel module level patterns that capture strain and pathogenicity-specific patterns of expression and helped identify important regulators of host response to influenza infection.

  18. Integrating Transcriptomic and Proteomic Data Using Predictive Regulatory Network Models of Host Response to Pathogens

    Science.gov (United States)

    Chasman, Deborah; Walters, Kevin B.; Lopes, Tiago J. S.; Eisfeld, Amie J.; Kawaoka, Yoshihiro; Roy, Sushmita

    2016-01-01

    Mammalian host response to pathogenic infections is controlled by a complex regulatory network connecting regulatory proteins such as transcription factors and signaling proteins to target genes. An important challenge in infectious disease research is to understand molecular similarities and differences in mammalian host response to diverse sets of pathogens. Recently, systems biology studies have produced rich collections of omic profiles measuring host response to infectious agents such as influenza viruses at multiple levels. To gain a comprehensive understanding of the regulatory network driving host response to multiple infectious agents, we integrated host transcriptomes and proteomes using a network-based approach. Our approach combines expression-based regulatory network inference, structured-sparsity based regression, and network information flow to infer putative physical regulatory programs for expression modules. We applied our approach to identify regulatory networks, modules and subnetworks that drive host response to multiple influenza infections. The inferred regulatory network and modules are significantly enriched for known pathways of immune response and implicate apoptosis, splicing, and interferon signaling processes in the differential response of viral infections of different pathogenicities. We used the learned network to prioritize regulators and study virus and time-point specific networks. RNAi-based knockdown of predicted regulators had significant impact on viral replication and include several previously unknown regulators. Taken together, our integrated analysis identified novel module level patterns that capture strain and pathogenicity-specific patterns of expression and helped identify important regulators of host response to influenza infection. PMID:27403523

  19. Skin conductance response to the pain of others predicts later costly helping.

    Directory of Open Access Journals (Sweden)

    Grit Hein

    Full Text Available People show autonomic responses when they empathize with the suffering of another person. However, little is known about how these autonomic changes are related to prosocial behavior. We measured skin conductance responses (SCRs and affect ratings in participants while either receiving painful stimulation themselves, or observing pain being inflicted on another person. In a later session, they could prevent the infliction of pain in the other by choosing to endure pain themselves. Our results show that the strength of empathy-related vicarious skin conductance responses predicts later costly helping. Moreover, the higher the match between SCR magnitudes during the observation of pain in others and SCR magnitude during self pain, the more likely a person is to engage in costly helping. We conclude that prosocial motivation is fostered by the strength of the vicarious autonomic response as well as its match with first-hand autonomic experience.

  20. Predicting the Response to Intravenous Immunoglobulins in an Animal Model of Chronic Neuritis

    Science.gov (United States)

    Pfaff, Johannes; Mathys, Christian; Mausberg, Anne K.; Bendszus, Martin; Pham, Mirko; Hartung, Hans-Peter; Kieseier, Bernd C.

    2016-01-01

    Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a disabling autoimmune disorder of the peripheral nervous system (PNS). Intravenous immunoglobulins (IVIg) are effective in CIDP, but the treatment response varies greatly between individual patients. Understanding this interindividual variability and predicting the response to IVIg constitute major clinical challenges in CIDP. We previously established intercellular adhesion molecule (ICAM)-1 deficient non-obese diabetic (NOD) mice as a novel animal model of CIDP. Here, we demonstrate that similar to human CIDP patients, ICAM-1 deficient NOD mice respond to IVIg treatment by clinical and histological measures. Nerve magnetic resonance imaging and histology demonstrated that IVIg ameliorates abnormalities preferentially in distal parts of the sciatic nerve branches. The IVIg treatment response also featured great heterogeneity allowing us to identify IVIg responders and non-responders. An increased production of interleukin (IL)-17 positively predicted IVIg treatment responses. In human sural nerve biopsy sections, high numbers of IL-17 producing cells were associated with younger age and shorter disease duration. Thus, our novel animal model can be utilized to identify prognostic markers of treatment responses in chronic inflammatory neuropathies and we identify IL-17 production as one potential such prognostic marker. PMID:27711247

  1. Stathmin protein level, a potential predictive marker for taxane treatment response in endometrial cancer.

    Directory of Open Access Journals (Sweden)

    Henrica M J Werner

    Full Text Available Stathmin is a prognostic marker in many cancers, including endometrial cancer. Preclinical studies, predominantly in breast cancer, have suggested that stathmin may additionally be a predictive marker for response to paclitaxel. We first evaluated the response to paclitaxel in endometrial cancer cell lines before and after stathmin knock-down. Subsequently we investigated the clinical response to paclitaxel containing chemotherapy in metastatic endometrial cancer in relation to stathmin protein level in tumors. Stathmin level was also determined in metastatic lesions, analyzing changes in biomarker status on disease progression. Knock-down of stathmin improved sensitivity to paclitaxel in endometrial carcinoma cell lines with both naturally higher and lower sensitivity to paclitaxel. In clinical samples, high stathmin level was demonstrated to be associated with poor response to paclitaxel containing chemotherapy and to reduced disease specific survival only in patients treated with such combination. Stathmin level increased significantly from primary to metastatic lesions. This study suggests, supported by both preclinical and clinical data, that stathmin could be a predictive biomarker for response to paclitaxel treatment in endometrial cancer. Re-assessment of stathmin level in metastatic lesions prior to treatment start may be relevant. Also, validation in a randomized clinical trial will be important.

  2. The maternal serological response to intrauterine Ureaplasma sp. infection and prediction of risk of preterm birth

    Directory of Open Access Journals (Sweden)

    Demelza Jane Ireland

    2014-12-01

    Full Text Available Preterm birth (PTB associated with intrauterine infection and inflammation (IUI is the major cause of early PTB less than 32 weeks gestation. Ureaplasma sp. are common commensals of the urogenital tract in pregnancy and are the most commonly identified microorganism in amniotic fluid of preterm pregnancies. While we have an understanding of the causal relationship between intraamniotic infection, inflammation and PTB, we are still unable to explain why vaginal Ureaplasma colonization is tolerated in some women but causes PTB in others. It is now known that placental tissues are frequently colonized by bacteria even in apparently healthy pregnancies delivered at term; usually this occurs in the absence of a significant local inflammatory response. It appears, therefore, that the site, nature and magnitude of the immune response to infiltrating microorganisms is key in determining pregnancy outcome. Some evidence exists that the maternal serological response to Ureaplasma sp. colonization may be predictive of adverse pregnancy outcome, although issues such as the importance of virulence factors (serovars and the timing, magnitude and functional consequences of the immune response await clarification. This mini-review discusses the evidence linking the maternal immune response to risk of PTB and the potential applications of maternal serological analysis for predicting obstetric outcome.

  3. Infant Responses to Maternal Still Face at 9 Months Predict Social Abilities at 18 Months

    OpenAIRE

    Yato, Yuko; Tanaka, Daisuke; Shinohara, Ryoji; Sugisawa, Yuka; Tanaka, Emiko; Tong, Lian; Yamakawa, Noriko; Anme, Tokie; Kawai, Masatoshi; Maeda, Tadahiko; Japan, Children's Study Group

    2010-01-01

    Background: This study investigated developmental change and stability in infant responses to the still-face (SF) situation, as well as predictive validity at age 18 months, focusing on autonomy and responsiveness.Methods: A total of 231 children (117 boys and 114 girls) and their Japanese mothers were observed in a face-to-face SF situation at two infant ages (4 and 9 months), as well as a caregiver-child teaching interaction at age 18 months. Each infant’s facial expression, gaze direction,...

  4. Infant Responses to Maternal Still Face at 9 Months Predict Social Abilities at 18 Months

    OpenAIRE

    Yato, Yuko; Tanaka, Daisuke; Shinohara, Ryoji; Sugisawa, Yuka; Tanaka, Emiko; Tong, Lian; Yamakawa, Noriko; Anme, Tokie; Kawai, Masatoshi; Maeda, Tadahiko; ,

    2010-01-01

    Background This study investigated developmental change and stability in infant responses to the still-face (SF) situation, as well as predictive validity at age 18 months, focusing on autonomy and responsiveness. Methods A total of 231 children (117 boys and 114 girls) and their Japanese mothers were observed in a face-to-face SF situation at two infant ages (4 and 9 months), as well as a caregiver-child teaching interaction at age 18 months. Each infant’s facial expression, gaze direction, ...

  5. Prediction analysis of dose equivalent responses of neutron dosemeters used at a MOX fuel facility.

    Science.gov (United States)

    Tsujimura, N; Yoshida, T; Takada, C

    2011-07-01

    To predict how accurately neutron dosemeters can measure the neutron dose equivalent (rate) in MOX fuel fabrication facility work environments, the dose equivalent responses of neutron dosemeters were calculated by the spectral folding method. The dosemeters selected included two types of personal dosemeter, namely a thermoluminescent albedo neutron dosemeter and an electronic neutron dosemeter, three moderator-based neutron survey meters, and one special instrument called an H(p)(10) monitor. The calculations revealed the energy dependences of the responses expected within the entire range of neutron spectral variations observed in neutron fields at workplaces. PMID:21498409

  6. Empirical Model Development for Predicting Shock Response on Composite Materials Subjected to Pyroshock Loading

    Science.gov (United States)

    Gentz, Steven J.; Ordway, David O; Parsons, David S.; Garrison, Craig M.; Rodgers, C. Steven; Collins, Brian W.

    2015-01-01

    The NASA Engineering and Safety Center (NESC) received a request to develop an analysis model based on both frequency response and wave propagation analyses for predicting shock response spectrum (SRS) on composite materials subjected to pyroshock loading. The model would account for near-field environment (approx. 9 inches from the source) dominated by direct wave propagation, mid-field environment (approx. 2 feet from the source) characterized by wave propagation and structural resonances, and far-field environment dominated by lower frequency bending waves in the structure. This report documents the outcome of the assessment.

  7. Empirical Model Development for Predicting Shock Response on Composite Materials Subjected to Pyroshock Loading: Appendices

    Science.gov (United States)

    Gentz, Steven J.; Ordway, David O.; Parsons, David S.; Garrison, Craig M.; Rodgers, C. Steven; Collins, Brian W.

    2015-01-01

    The NASA Engineering and Safety Center (NESC) received a request to develop an analysis model based on both frequency response and wave propagation analyses for predicting shock response spectrum (SRS) on composite materials subjected to pyroshock loading. The model would account for near-field environment (approx. 9 inches from the source) dominated by direct wave propagation, mid-field environment (approx. 2 feet from the source) characterized by wave propagation and structural resonances, and far-field environment dominated by lower frequency bending waves in the structure. This document contains appendices to the Volume I report.

  8. Empirical Model Development for Predicting Shock Response on Composite Materials Subjected to Pyroshock Loading. [Appendices

    Science.gov (United States)

    Gentz, Steven J.; Ordway, David O.; Parsons, David S.; Garrison, Craig M.; Rodgers, C. Steven; Collins, Brian W.

    2015-01-01

    The NASA Engineering and Safety Center (NESC) received a request to develop an analysis model based on both frequency response and wave propagation analyses for predicting shock response spectrum (SRS) on composite materials subjected to pyroshock loading. The model would account for near-field environment (9 inches from the source) dominated by direct wave propagation, mid-field environment (approximately 2 feet from the source) characterized by wave propagation and structural resonances, and far-field environment dominated by lower frequency bending waves in the structure. This document contains appendices to the Volume I report.

  9. Fractional Diffusion Based Modelling and Prediction of Human Brain Response to External Stimuli

    Directory of Open Access Journals (Sweden)

    Hamidreza Namazi

    2015-01-01

    Full Text Available Human brain response is the result of the overall ability of the brain in analyzing different internal and external stimuli and thus making the proper decisions. During the last decades scientists have discovered more about this phenomenon and proposed some models based on computational, biological, or neuropsychological methods. Despite some advances in studies related to this area of the brain research, there were fewer efforts which have been done on the mathematical modeling of the human brain response to external stimuli. This research is devoted to the modeling and prediction of the human EEG signal, as an alert state of overall human brain activity monitoring, upon receiving external stimuli, based on fractional diffusion equations. The results of this modeling show very good agreement with the real human EEG signal and thus this model can be used for many types of applications such as prediction of seizure onset in patient with epilepsy.

  10. Prediction of thermal and mechanical stress-strain responses of TMC's subjected to complex TMF histories

    Science.gov (United States)

    Johnson, W. S.; Mirdamadi, M.

    1994-01-01

    This paper presents an experimental and analytical evaluation of cross-plied laminates of Ti-15V-3Cr-3Al-3Sn (Ti-15-3) matrix reinforced with continuous silicon-carbide fibers (SCS-6) subjected to a complex TMF loading profile. Thermomechanical fatigue test techniques were developed to conduct a simulation of a generic hypersonic flight profile. A micromechanical analysis was used. The analysis predicts the stress-strain response of the laminate and of the constituents in each ply during thermal and mechanical cycling by using only constituent properties as input. The fiber was modeled as elastic with transverse orthotropic and temperature-dependent properties. The matrix was modeled using a thermoviscoplastic constitutive relation. The fiber transverse modulus was reduced in the analysis to simulate the fiber-matrix interface failures. Excellent correlation was found between measured and predicted laminate stress-strain response due to generic hypersonic flight profile when fiber debonding was modeled.

  11. How to predict community responses to perturbations in the face of imperfect knowledge and network complexity

    Science.gov (United States)

    Aufderheide, Helge; Rudolf, Lars; Gross, Thilo; Lafferty, Kevin D.

    2013-01-01

    Recent attempts to predict the response of large food webs to perturbations have revealed that in larger systems increasingly precise information on the elements of the system is required. Thus, the effort needed for good predictions grows quickly with the system's complexity. Here, we show that not all elements need to be measured equally well, suggesting that a more efficient allocation of effort is possible. We develop an iterative technique for determining an efficient measurement strategy. In model food webs, we find that it is most important to precisely measure the mortality and predation rates of long-lived, generalist, top predators. Prioritizing the study of such species will make it easier to understand the response of complex food webs to perturbations.

  12. AAA gunnermodel based on observer theory. [predicting a gunner's tracking response

    Science.gov (United States)

    Kou, R. S.; Glass, B. C.; Day, C. N.; Vikmanis, M. M.

    1978-01-01

    The Luenberger observer theory is used to develop a predictive model of a gunner's tracking response in antiaircraft artillery systems. This model is composed of an observer, a feedback controller and a remnant element. An important feature of the model is that the structure is simple, hence a computer simulation requires only a short execution time. A parameter identification program based on the least squares curve fitting method and the Gauss Newton gradient algorithm is developed to determine the parameter values of the gunner model. Thus, a systematic procedure exists for identifying model parameters for a given antiaircraft tracking task. Model predictions of tracking errors are compared with human tracking data obtained from manned simulation experiments. Model predictions are in excellent agreement with the empirical data for several flyby and maneuvering target trajectories.

  13. Predicting multi-class responses to preoperative chemoradiotherapy in rectal cancer patients

    International Nuclear Information System (INIS)

    Preoperative chemoradiotherapy (CRT) has become a widely used treatment for improving local control of disease and increasing survival rates of rectal cancer patients. We aimed to identify a set of genes that can be used to predict responses to CRT in patients with rectal cancer. Gene expression profiles of pre-therapeutic biopsy specimens obtained from 77 rectal cancer patients were analyzed using DNA microarrays. The response to CRT was determined using the Dworak tumor regression grade: grade 1 (minimal, MI), grade 2 (moderate, MO), grade 3 (near total, NT), or grade 4 (total, TO). Top ranked genes for three different feature scores such as a p-value (pval), a rank product (rank), and a normalized product (norm) were selected to distinguish pre-defined groups such as complete responders (TO) from the MI, MO, and NT groups. Among five different classification algorithms, supporting vector machine (SVM) with the top 65 norm features performed at the highest accuracy for predicting MI using a 5-fold cross validation strategy. On the other hand, 98 pval features were selected for predicting TO by elastic net (EN). Finally we combined TO- and MI-finder models to build a three-class classification model and validated it using an independent dataset of rectal cancer mRNA expression. We identified MI- and TO-finders for predicting preoperative CRT responses, and validated these data using an independent public dataset. This stepwise prediction model requires further evaluation in clinical studies in order to develop personalized preoperative CRT in patients with rectal cancer. The online version of this article (doi:10.1186/s13014-016-0623-9) contains supplementary material, which is available to authorized users

  14. Predicting zooplankton response to environmental changes in a temperate estuarine ecosystem

    OpenAIRE

    Marques, Sónia; Azeiteiro, Ulisses; Leandro, Sérgio; Queiroga, Henrique; Primo, Ana; Martinho, Filipe; Viegas, Ivan; Pardal, Miguel

    2008-01-01

    Abstract A novel strategy that allows to predict the responses of zooplanktonic species to environmental conditions in an estuarine temperate ecosystem (Mondego estuary) is presented. It uses 12 indicator species from the zooplanktonic Mondego database (102 species) that are common members of the different habitats, characterized by their specific hydrological conditions. Indicator-species analysis (ISA) was used to define and describe which species were typical of each of the five sampling ...

  15. Predicting volume responsiveness in spontaneously breathing patients: still a challenging problem

    OpenAIRE

    Magder, S

    2006-01-01

    The prediction of which patients respond to fluid infusion and which patients do not is an important issue in the intensive care setting. Assessment of this response by monitoring changes in some hemodynamic characteristics in relation to spontaneous breathing efforts would be very helpful for the management of the critically ill. This unfortunately remains a difficult clinical problem, as discussed in the previous issue of the journal. Technical factors and physiological factors limit the us...

  16. Simple regional strain pattern analysis to predict response to cardiac resynchronization therapy

    DEFF Research Database (Denmark)

    Risum, Niels; Jons, Christian; Olsen, Niels T;

    2012-01-01

    A classical strain pattern of early contraction in one wall and prestretching of the opposing wall followed by late contraction has previously been associated with left bundle branch block (LBBB) activation and short-term response to cardiac resynchronization therapy (CRT). Aims of this study were...... to establish the long-term predictive value of an LBBB-related strain pattern and to identify changes in contraction patterns during short-term and long-term CRT....

  17. Diffusion-weighted magnetic resonance imaging to predict response of hepatocellular carcinoma to chemoembolization

    Institute of Scientific and Technical Information of China (English)

    Johnathan; C; Chung; Neel; K; Naik; Robert; J; Lewandowski; Mary; F; Mulcahy; Laura; M; Kulik; Kent; T; Sato; Robert; K; Ryu; Riad; Salem; Andrew; C; Larson; Reed; A; Omary

    2010-01-01

    AIM: To investigate whether intra-procedural diffusion- weighted magnetic resonance imaging can predict response of hepatocellular carcinoma (HCC) during trans- catheter arterial chemoembolization (TACE). METHODS: Sixteen patients (15 male), aged 59 ±11 years (range: 42-81 years) underwent a total of 21 separate treatments for unresectable HCC in a hybrid magnetic resonance/interventional radiology suite. Ana- tomical imaging and diffusion-weighted imaging (b = 0, 500 s/mm2) were performed on a 1.5-T unit. ...

  18. A validated miRNA profile predicts response to therapy in esophageal adenocarcinoma

    OpenAIRE

    SKINNER, HEATH D.; Lee, Jeffrey H.; Manoop S. Bhutani; Weston, Brian; Hofstetter, Wayne; Komaki, Ritsuko; Shiozaki, Hironori; Wadhwa, Roopma; Sudo, Kazuki; Elimova, Elena; Song, Shumei; Ye, Yuanqing; Huang, Maosheng; Ajani, Jaffer; Wu, Xifeng

    2014-01-01

    BACKGROUND In the current study we present a validated miRNA signature to predict pathologic complete response (pCR) to neoadjuvant chemoradiation in esophageal adenocarcinoma. METHODS Three patient cohorts (discovery, n = 10; model, n = 43; and validation, n = 65) with locally advanced esophageal adenocarcinoma were analyzed. In the discovery cohort 754 miRNAs were examined in pretreatment tumor biopsy specimens using a TaqMan array. Of these, the 44 most significantly altered between tumors...

  19. Immune Profiles to Predict Response to Desensitization Therapy in Highly HLA-Sensitized Kidney Transplant Candidates

    OpenAIRE

    Yabu, Julie M.; Siebert, Janet C.; Maecker, Holden T.

    2016-01-01

    Background Kidney transplantation is the most effective treatment for end-stage kidney disease. Sensitization, the formation of human leukocyte antigen (HLA) antibodies, remains a major barrier to successful kidney transplantation. Despite the implementation of desensitization strategies, many candidates fail to respond. Current progress is hindered by the lack of biomarkers to predict response and to guide therapy. Our objective was to determine whether differences in immune and gene profile...

  20. Vitamin D Receptor gene polymorphism may predict response to vitamin D intake and bone turnover

    Directory of Open Access Journals (Sweden)

    G Ahangari

    2010-01-01

    Full Text Available "n  "n Background and the purpose of the study:The molecular and functional basis of the VDR polymorphisms is fundamental to appreciate their potential clinical implications. The rationale of this study was to determine the level of serum vitamin D response to vitamin D intake in different genotypes of VDR (FokI polymorphism and its effect on the bone turnover in postmenopausal women.  Methods:The subjects for the study were 312 pre and post-menopausal women aged between 20-75 year randomly selected from the participants of Iranian multicenter osteoporosis study. After an overnight fast, 4ml of peripheral blood was taken and centrifuged to separate serum for measurement of serum parathyroid hormone, 25 hydroxyvitamin D, osteocalcin and cross laps. The FokI polymorphism in exon 2 of the VDR gene was detected by the polymerase chain reaction-restriction fragment length polymorphism Results and major conclusion: FOKI genotype predicted serum cross laps after adjustment for age, menopausal status, serum vitamin D (p<0.001 but did not find significant prediction regarding serum osteocalcin (p=0.3.Also in this model FOKI genotype predicted serum vitamin D after adjustment for age, menopausal status, calcium and vitamin D intake (p<0.001.VDR gene polymorphism may modifies response to vitamin D intake and predicts bone turnover.   "n 

  1. Predicting Themomechanical Responses of Polymer Thin Films and Nanocomposites via an Innovative Coarse-grained Approach

    Science.gov (United States)

    Xia, Wenjie; Hsu, David; Keten, Sinan

    Understanding and predicting the thermomechanical responses of nanoscale polymer systems are very challenging as their responses are greatly influenced by many factors, such as interfacial energy, filler volume fraction and molecule weight, giving rise to the presence of nanoscale interface and free surface. To overcome these issues, here we employ a novel atomistically informed coarse-grained computational technique, called thermomechanically consistent coarse graining (TCCG), to investigate how the nanoscale interface and free surface influence the elastic modulus (E) and glass transition temperature (Tg) of polymer films and nanocomposites. By performing tensile tests and nanoindentation simulations, we are able to predict the size dependent elastic properties of polymer films and quantify the length scale of the local mechanical interphase. Finally, taking cellulose nanocrystal (CNC) and poly(methyl-methacrylate) (PMMA) nanocomposites as a relevant model system, we present a multi-scale framework built upon our CG approach to allow the prediction of Tg of nanocomposite as a function of interfacial energy and filler volume fractions by drawing the analogy between thin film and nanocomposites. Our established multi-scale framework is validated by recent experiments and breaks new ground in predicting, without any empirical parameters, key structure-property relationships for polymer nanomaterials.

  2. Rapid brain responses independently predict gain maximization and loss minimization during economic decision making.

    Science.gov (United States)

    San Martín, René; Appelbaum, Lawrence G; Pearson, John M; Huettel, Scott A; Woldorff, Marty G

    2013-04-17

    Success in many decision-making scenarios depends on the ability to maximize gains and minimize losses. Even if an agent knows which cues lead to gains and which lead to losses, that agent could still make choices yielding suboptimal rewards. Here, by analyzing event-related potentials (ERPs) recorded in humans during a probabilistic gambling task, we show that individuals' behavioral tendencies to maximize gains and to minimize losses are associated with their ERP responses to the receipt of those gains and losses, respectively. We focused our analyses on ERP signals that predict behavioral adjustment: the frontocentral feedback-related negativity (FRN) and two P300 (P3) subcomponents, the frontocentral P3a and the parietal P3b. We found that, across participants, gain maximization was predicted by differences in amplitude of the P3b for suboptimal versus optimal gains (i.e., P3b amplitude difference between the least good and the best gains). Conversely, loss minimization was predicted by differences in the P3b amplitude to suboptimal versus optimal losses (i.e., difference between the worst and the least bad losses). Finally, we observed that the P3a and P3b, but not the FRN, predicted behavioral adjustment on subsequent trials, suggesting a specific adaptive mechanism by which prior experience may alter ensuing behavior. These findings indicate that individual differences in gain maximization and loss minimization are linked to individual differences in rapid neural responses to monetary outcomes.

  3. Do the acute platelet responses of patients with immune thrombocytopenic purpura (ITP) to IV anti-D and to IV gammaglobulin predict response to subsequent splenectomy?

    Science.gov (United States)

    Bussel, J B; Kaufmann, C P; Ware, R E; Woloski, B M

    2001-05-01

    The acute platelet response to Intravenous Gammaglobulin (IVIG) has been reported to predict response to subsequent splenectomy of patients with ITP. The current study was undertaken to determine if the platelet response to IV anti-D (Winrho-SDF) predicts response to subsequent splenectomy. The 61 HIV-uninfected children and adults in this study had taken part in the pre-licensing studies of IV anti-D and were all those who not only had evaluable platelet responses to IV anti-D but also had undergone splenectomy and had information available describing its 1-year outcome. Results of treatment with IVIG were available in 38 of these 61 patients. Neither response to the initial infusion of IV anti-D, nor response to the initial or last IVIG, predicted the response in either children or adults to subsequent splenectomy. However, response to the last anti-D infusion in adults was strongly correlated (P = 0.003) to response to subsequent splenectomy as was hemolysis >/=2.0 gm/dl after IV anti-D (P = 0.03). There was no overall relationship between response to IV anti-D or IVIG, and response to subsequent splenectomy. However, a good platelet response in adults to the last IV anti-D and a hemoglobin decrease >/=2.0 gm/dl both appeared to predict response to subsequent splenectomy. PMID:11279654

  4. Measurement and Prediction of the Thermomechanical Response of Shape Memory Alloy Hybrid Composite Beams

    Science.gov (United States)

    Davis, Brian; Turner, Travis L.; Seelecke, Stefan

    2005-01-01

    Previous work at NASA Langley Research Center (LaRC) involved fabrication and testing of composite beams with embedded, pre-strained shape memory alloy (SMA) ribbons within the beam structures. That study also provided comparison of experimental results with numerical predictions from a research code making use of a new thermoelastic model for shape memory alloy hybrid composite (SMAHC) structures. The previous work showed qualitative validation of the numerical model. However, deficiencies in the experimental-numerical correlation were noted and hypotheses for the discrepancies were given for further investigation. The goal of this work is to refine the experimental measurement and numerical modeling approaches in order to better understand the discrepancies, improve the correlation between prediction and measurement, and provide rigorous quantitative validation of the numerical analysis/design tool. The experimental investigation is refined by a more thorough test procedure and incorporation of higher fidelity measurements such as infrared thermography and projection moire interferometry. The numerical results are produced by a recently commercialized version of the constitutive model as implemented in ABAQUS and are refined by incorporation of additional measured parameters such as geometric imperfection. Thermal buckling, post-buckling, and random responses to thermal and inertial (base acceleration) loads are studied. The results demonstrate the effectiveness of SMAHC structures in controlling static and dynamic responses by adaptive stiffening. Excellent agreement is achieved between the predicted and measured results of the static and dynamic thermomechanical response, thereby providing quantitative validation of the numerical tool.

  5. Biomarkers for predicting clinical response to immunosuppressive therapy in aplastic anemia.

    Science.gov (United States)

    Narita, Atsushi; Kojima, Seiji

    2016-08-01

    The decision to select hematopoietic stem cell transplantation (HSCT) or immunosuppressive therapy (IST) as initial therapy in acquired aplastic anemia (AA) is currently based on patient age and the availability of a human leukocyte antigen (HLA)-matched donor. Although IST is a promising treatment option, the ability to predict its long-term outcomes remains poor due to refractoriness, relapses, and the risk of clonal evolution. Several predictive biomarkers for response to IST have been posited, including age, gender, pre-treatment blood cell counts, cytokines, gene mutations, paroxysmal nocturnal hemoglobinuria (PNH), and telomere length (TL). While previous studies have provided substantial biological insights into the utility of IST, the prognostic power of the reported biomarkers is currently insufficient to contribute to clinical decision making. Recently, a large retrospective analysis proposed the combination of minor PNH clones and TL as an efficient predictor of IST response. Identification of a reliable predictor would provide a useful tool for determining the most appropriate treatment choice for AA patients, including up-front HSCT from HLA-matched unrelated donor. The present review summarizes studies evaluating the utility of biomarkers in predicting the clinical response to IST of patients with AA, and provides a baseline for prospective studies aimed at validating previously reported biomarkers. PMID:27091471

  6. Algorithms to Improve the Prediction of Postprandial Insulinaemia in Response to Common Foods.

    Science.gov (United States)

    Bell, Kirstine J; Petocz, Peter; Colagiuri, Stephen; Brand-Miller, Jennie C

    2016-01-01

    Dietary patterns that induce excessive insulin secretion may contribute to worsening insulin resistance and beta-cell dysfunction. Our aim was to generate mathematical algorithms to improve the prediction of postprandial glycaemia and insulinaemia for foods of known nutrient composition, glycemic index (GI) and glycemic load (GL). We used an expanded database of food insulin index (FII) values generated by testing 1000 kJ portions of 147 common foods relative to a reference food in lean, young, healthy volunteers. Simple and multiple linear regression analyses were applied to validate previously generated equations for predicting insulinaemia, and develop improved predictive models. Large differences in insulinaemic responses within and between food groups were evident. GL, GI and available carbohydrate content were the strongest predictors of the FII, explaining 55%, 51% and 47% of variation respectively. Fat, protein and sugar were significant but relatively weak predictors, accounting for only 31%, 7% and 13% of the variation respectively. Nutritional composition alone explained only 50% of variability. The best algorithm included a measure of glycemic response, sugar and protein content and explained 78% of variation. Knowledge of the GI or glycaemic response to 1000 kJ portions together with nutrient composition therefore provides a good approximation for ranking of foods according to their "insulin demand".

  7. Algorithms to Improve the Prediction of Postprandial Insulinaemia in Response to Common Foods

    Directory of Open Access Journals (Sweden)

    Kirstine J. Bell

    2016-04-01

    Full Text Available Dietary patterns that induce excessive insulin secretion may contribute to worsening insulin resistance and beta-cell dysfunction. Our aim was to generate mathematical algorithms to improve the prediction of postprandial glycaemia and insulinaemia for foods of known nutrient composition, glycemic index (GI and glycemic load (GL. We used an expanded database of food insulin index (FII values generated by testing 1000 kJ portions of 147 common foods relative to a reference food in lean, young, healthy volunteers. Simple and multiple linear regression analyses were applied to validate previously generated equations for predicting insulinaemia, and develop improved predictive models. Large differences in insulinaemic responses within and between food groups were evident. GL, GI and available carbohydrate content were the strongest predictors of the FII, explaining 55%, 51% and 47% of variation respectively. Fat, protein and sugar were significant but relatively weak predictors, accounting for only 31%, 7% and 13% of the variation respectively. Nutritional composition alone explained only 50% of variability. The best algorithm included a measure of glycemic response, sugar and protein content and explained 78% of variation. Knowledge of the GI or glycaemic response to 1000 kJ portions together with nutrient composition therefore provides a good approximation for ranking of foods according to their “insulin demand”.

  8. Alexithymia predicts arousal-based processing deficits and discordance between emotion response systems during emotional imagery.

    Science.gov (United States)

    Peasley-Miklus, Catherine E; Panayiotou, Georgia; Vrana, Scott R

    2016-03-01

    Alexithymia is believed to involve deficits in emotion processing and imagery ability. Previous findings suggest that it is especially related to deficits in processing the arousal dimension of emotion, and that discordance may exist between self-report and physiological responses to emotional stimuli in alexithymia. The current study used a well-established emotional imagery paradigm to examine emotion processing deficits and discordance in participants (N = 86) selected based on their extreme scores on the Toronto Alexithymia Scale-20. Physiological (skin conductance, heart rate, and corrugator and zygomaticus electromyographic responses) and self-report (valence, arousal ratings) responses were monitored during imagery of anger, fear, joy, and neutral scenes and emotionally neutral high arousal (action) scenes. Results from regression analyses indicated that alexithymia was largely unrelated to responses on valence-based measures (facial electromyography, valence ratings), but that it was related to arousal-based measures. Specifically, alexithymia was related to higher heart rate during neutral and lower heart rate during fear imagery. Alexithymia did not predict differential responses to action versus neutral imagery, suggesting specificity of deficits to emotional contexts. Evidence for discordance between physiological responses and self-report in alexithymia was obtained from within-person analyses using multilevel modeling. Results are consistent with the idea that alexithymic deficits are specific to processing emotional arousal, and suggest difficulties with parasympathetic control and emotion regulation. Alexithymia is also associated with discordance between self-reported emotional experience and physiological response to emotion, consistent with prior evidence.

  9. The eye is listening: Music-induced arousal and individual differences predict pupillary responses

    Directory of Open Access Journals (Sweden)

    Bruno eGingras

    2015-11-01

    Full Text Available Pupillary responses are a well-known indicator of emotional arousal but have not yet been systematically investigated in response to music. Here, we measured pupillary dilations evoked by short musical excerpts normalized for intensity and selected for their stylistic uniformity. Thirty participants (15 females provided subjective ratings of music-induced felt arousal, tension, pleasantness and familiarity for 80 classical music excerpts. The pupillary responses evoked by these excerpts were measured in another thirty participants (15 females. We probed the role of listener-specific characteristics such as mood, stress reactivity, self-reported role of music in life, liking for the selected excerpts, as well as of subjective responses to music, in pupillary responses. Linear mixed model analyses showed that a greater role of music in life was associated with larger dilations, and that larger dilations were also predicted for excerpts rated as more arousing or tense. However, an interaction between arousal and liking for the excerpts suggested that pupillary responses were modulated less strongly by arousal when the excerpts were particularly liked. An analogous interaction was observed between tension and liking. Additionally, males exhibited larger dilations than females. Overall, these findings suggest a complex interplay between bottom-up and top-down influences on pupillary responses to music.

  10. Ovarian response prediction in GnRH antagonist treatment for IVF using anti-Müllerian hormone

    NARCIS (Netherlands)

    Hamdine, O.; Eijkemans, M. J C; Lentjes, E. W G; Torrance, H. L.; Macklon, N. S.; Fauser, B. C J M; Broekmans, F. J.

    2015-01-01

    STUDY QUESTION What is the clinical value of anti-Müllerian hormone (AMH) for the prediction of high or low ovarian response in controlled ovarian stimulation for IVF using GnRH antagonist treatment? SUMMARY ANSWER AMH as a single test has substantial accuracy for ovarian response prediction in GnRH

  11. Personalized medicine in psoriasis: developing a genomic classifier to predict histological response to Alefacept

    Directory of Open Access Journals (Sweden)

    Haider Asifa S

    2010-02-01

    Full Text Available Abstract Background Alefacept treatment is highly effective in a select group patients with moderate-to-severe psoriasis, and is an ideal candidate to develop systems to predict who will respond to therapy. A clinical trial of 22 patients with moderate to severe psoriasis treated with alefacept was conducted in 2002-2003, as a mechanism of action study. Patients were classified as responders or non-responders to alefacept based on histological criteria. Results of the original mechanism of action study have been published. Peripheral blood was collected at the start of this clinical trial, and a prior analysis demonstrated that gene expression in PBMCs differed between responders and non-responders, however, the analysis performed could not be used to predict response. Methods Microarray data from PBMCs of 16 of these patients was analyzed to generate a treatment response classifier. We used a discriminant analysis method that performs sample classification from gene expression data, via "nearest shrunken centroid method". Centroids are the average gene expression for each gene in each class divided by the within-class standard deviation for that gene. Results A disease response classifier using 23 genes was created to accurately predict response to alefacept (12.3% error rate. While the genes in this classifier should be considered as a group, some of the individual genes are of great interest, for example, cAMP response element modulator (CREM, v-MAF avian musculoaponeurotic fibrosarcoma oncogene family (MAFF, chloride intracellular channel protein 1 (CLIC1, also called NCC27, NLR family, pyrin domain-containing 1 (NLRP1, and CCL5 (chemokine, cc motif, ligand 5, also called regulated upon activation, normally T expressed, and presumably secreted/RANTES. Conclusions Although this study is small, and based on analysis of existing microarray data, we demonstrate that a treatment response classifier for alefacept can be created using gene

  12. Rapid Detection of Neutrophil Oxidative Burst Capacity is Predictive of Whole Blood Cytokine Responses.

    Directory of Open Access Journals (Sweden)

    Philip J Vernon

    Full Text Available Maladaptive immune responses, particularly cytokine and chemokine-driven, are a significant contributor to the deleterious inflammation present in many types of injury and infection. Widely available applications to rapidly assess individual inflammatory capacity could permit identification of patients at risk for exacerbated immune responses and guide therapy. Here we evaluate neutrophil oxidative burst (NOX capacity measured by plate reader to immuno-type Rhesus Macaques as an acute strategy to rapidly detect inflammatory capacity and predict maladaptive immune responses as assayed by cytokine array.Whole blood was collected from anesthetized Rhesus Macaques (n = 25 and analyzed for plasma cytokine secretion (23-plex Luminex assay and NOX capacity. For cytokine secretion, paired samples were either unstimulated or ex-vivo lipopolysaccharide (LPS-stimulated (100μg/mL/24h. NOX capacity was measured in dihydrorhodamine-123 loaded samples following phorbol 12-myristate 13-acetate (PMA/ionomycin treatment. Pearson's test was utilized to correlate NOX capacity with cytokine secretion, p<0.05 considered significant.LPS stimulation induced secretion of the inflammatory molecules G-CSF, IL-1β, IL-1RA, IL-6, IL-10, IL-12/23(p40, IL-18, MIP-1α, MIP-1β, and TNFα. Although values were variable, several cytokines correlated with NOX capacity, p-values≤0.0001. Specifically, IL-1β (r = 0.66, IL-6 (r = 0.74, the Th1-polarizing cytokine IL-12/23(p40 (r = 0.78, and TNFα (r = 0.76 were strongly associated with NOX.NOX capacity correlated with Th1-polarizing cytokine secretion, indicating its ability to rapidly predict inflammatory responses. These data suggest that NOX capacity may quickly identify patients at risk for maladaptive immune responses and who may benefit from immuno-modulatory therapies. Future studies will assess the in-vivo predictive value of NOX in animal models of immune-mediated pathologies.

  13. The prediction of ovarian response in in vitro fertilization-embryo transfer cycles

    Institute of Scientific and Technical Information of China (English)

    LIN Wen-qin; Yu Rong; YE Bi-lu; LIN Jin-ju; YANG Hai-yan

    2008-01-01

    Objective:To indentify the predictive parameters of ovarian response in in vitro fertilization-embryo transfer(IVF-ET)cycles,Methods:one hundred and six patients were administered GnRH-a/ rFSH/ human chorionic gonadotrophin(HCG)for ovarian stimulation.The following predictive parameters were examined,age,the basal level of FSH,mean ovarian volume,total of antral follicle count(AFC),the ratio of FSH/LH and the concentration of inhibin B after down-regulation.Ovarian response was assessed by the number of oocytes retrieved and the dosage of gonado-trophins(Can)used.Results:Correlations between predictive parameters and assessment indices of ovarian response were as follows:The basal FSH level and the ratio of FSH/LH showed a negative correlation with the number of oocyte obtained(r =-0.192,r=-0.227,respectively),while AFC and the concentration of inhibin B after down-regulation posi-tively correlated with the number of oocyte obtained(r=0.316,r=0.523,respectively),AFC,the mean ovarian volume and the concentration of inhibin B after down-regulation showed a negative correlation with the dosage of Gn used(r=-0.245,r=-0.294,r=-0.241,respectively),the ratio of FSH/ LH showed a positive correlation with the dosage of Gn used(r=0.255).Multiple regression analysis showed that inhibin B was the best predictor for the number of retrieved oocyte,followed by AFC,while the ovarian volume was the most important predictive parameter for the dosage of Gn used,then the ratio of FSH/LH.Conclusions:The level of inhibin B after down-regulation is the best predictor of ovarian response in IVF-ET.However,it's not yet a widely available test due to its high cost.AFC,by simple,non-invasive trsnsvaginal ultra-sound scan,could be the first applicable option in predicting ovarian response before IVF treatment.

  14. Integrated Experimental and Modeling Studies to Predict the Impact Response of Explosives and Propellants

    Energy Technology Data Exchange (ETDEWEB)

    Maienschein, J L; Nichols III, A L; Reaugh, J E; McClelland, M E; Hsu, P C

    2005-05-25

    Understanding and predicting the impact response of explosives and propellants remains a challenging area in the energetic materials field. Efforts are underway at LLNL (and other laboratories) to apply modern diagnostic tools and computational analysis to move beyond the current level of imprecise approximations towards a predictive approach more closely based on fundamental understanding of the relevant mechanisms. In this paper we will discuss a set of underlying mechanisms that govern the impact response of explosives and propellants: (a) mechanical insult (impact) leading to material damage and/or direct ignition; (b) ignition leading to flame spreading; (c) combustion being driven by flame spreading, perhaps in damaged materials; (d) combustion causing further material damage; (e) combustion leading to pressure build-up or relief; (f) pressure changes driving the rates of combustion and flame spread; (g) pressure buildup leading to structural response and damage, which causes many of the physical hazards. We will briefly discuss our approach to modeling up these mechanistic steps using ALE 3D, the LLNL hydrodynamic code with fully coupled chemistry, heat flow, mass transfer, and slow mechanical motion as well as hydrodynamic processes. We will identify the necessary material properties needed for our models, and will discuss our experimental efforts to characterize these properties and the overall mechanistic steps, in order to develop and parameterize the models in ALE 3D and to develop a qualitative understanding of impact response.

  15. Unsupervised feature learning improves prediction of human brain activity in response to natural images.

    Directory of Open Access Journals (Sweden)

    Umut Güçlü

    2014-08-01

    Full Text Available Encoding and decoding in functional magnetic resonance imaging has recently emerged as an area of research to noninvasively characterize the relationship between stimulus features and human brain activity. To overcome the challenge of formalizing what stimulus features should modulate single voxel responses, we introduce a general approach for making directly testable predictions of single voxel responses to statistically adapted representations of ecologically valid stimuli. These representations are learned from unlabeled data without supervision. Our approach is validated using a parsimonious computational model of (i how early visual cortical representations are adapted to statistical regularities in natural images and (ii how populations of these representations are pooled by single voxels. This computational model is used to predict single voxel responses to natural images and identify natural images from stimulus-evoked multiple voxel responses. We show that statistically adapted low-level sparse and invariant representations of natural images better span the space of early visual cortical representations and can be more effectively exploited in stimulus identification than hand-designed Gabor wavelets. Our results demonstrate the potential of our approach to better probe unknown cortical representations.

  16. Model-based Comparative Prediction of Transcription-Factor Binding Motifs in Anabolic Responses in Bone

    Institute of Scientific and Technical Information of China (English)

    Andy; B.; Chen; Kazunori; Hamamura; Guohua; Wang; Weirong; Xing; Subburaman; Mohan; Hiroki; Yokota; Yunlong; Liu

    2007-01-01

    Understanding the regulatory mechanism that controls the alteration of global gene expression patterns continues to be a challenging task in computational biology. We previously developed an ant algorithm, a biologically-inspired computational technique for microarray data, and predicted putative transcription-factor binding motifs (TFBMs) through mimicking interactive behaviors of natural ants. Here we extended the algorithm into a set of web-based software, Ant Modeler, and applied it to investigate the transcriptional mechanism underlying bone formation. Mechanical loading and administration of bone morphogenic proteins (BMPs) are two known treatments to strengthen bone. We addressed a question: Is there any TFBM that stimulates both "anabolic responses of mechanical loading" and "BMP-mediated osteogenic signaling"? Although there is no significant overlap among genes in the two responses, a comparative model-based analysis suggests that the two independent osteogenic processes employ common TFBMs, such as a stress responsive element and a motif for peroxisome proliferator-activated recep- tor (PPAR). The post-modeling in vitro analysis using mouse osteoblast cells sup- ported involvements of the predicted TFBMs such as PPAR, Ikaros 3, and LMO2 in response to mechanical loading. Taken together, the results would be useful to derive a set of testable hypotheses and examine the role of specific regulators in complex transcriptional control of bone formation.

  17. Novel enzymatic assay predicts minoxidil response in the treatment of androgenetic alopecia.

    Science.gov (United States)

    Goren, Andy; Castano, Juan Antonio; McCoy, John; Bermudez, Fernando; Lotti, Torello

    2014-01-01

    Topical minoxidil is the most common drug used for the treatment of androgenetic alopecia (AGA) in men and women. Although topical minoxidil exhibits a good safety profile, the efficacy in the overall population remains relatively low at 30-40%. To observe significant improvement in hair growth, minoxidil is typically used daily for a period of at least 3-4 months. Due to the significant time commitment and low response rate, a biomarker for predicting patient response prior to therapy would be advantageous. Minoxidil is converted in the scalp to its active form, minoxidil sulfate, by the sulfotransferase enzyme SULT1A1. We hypothesized that SULT1A1 enzyme activity in the hair follicle correlates with minoxidil response for the treatment of AGA. Our preliminary retrospective study of a SULT1A1 activity assay demonstrates 95% sensitivity and 73% specificity in predicting minoxidil treatment response for AGA. A larger prospective study is now under way to further validate this novel assay. PMID:24283387

  18. HLA Class-II Associated HIV Polymorphisms Predict Escape from CD4+ T Cell Responses.

    Directory of Open Access Journals (Sweden)

    Nathan Erdmann

    2015-08-01

    Full Text Available Antiretroviral therapy, antibody and CD8+ T cell-mediated responses targeting human immunodeficiency virus-1 (HIV-1 exert selection pressure on the virus necessitating escape; however, the ability of CD4+ T cells to exert selective pressure remains unclear. Using a computational approach on HIV gag/pol/nef sequences and HLA-II allelic data, we identified 29 HLA-II associated HIV sequence polymorphisms or adaptations (HLA-AP in an African cohort of chronically HIV-infected individuals. Epitopes encompassing the predicted adaptation (AE or its non-adapted (NAE version were evaluated for immunogenicity. Using a CD8-depleted IFN-γ ELISpot assay, we determined that the magnitude of CD4+ T cell responses to the predicted epitopes in controllers was higher compared to non-controllers (p<0.0001. However, regardless of the group, the magnitude of responses to AE was lower as compared to NAE (p<0.0001. CD4+ T cell responses in patients with acute HIV infection (AHI demonstrated poor immunogenicity towards AE as compared to NAE encoded by their transmitted founder virus. Longitudinal data in AHI off antiretroviral therapy demonstrated sequence changes that were biologically confirmed to represent CD4+ escape mutations. These data demonstrate an innovative application of HLA-associated polymorphisms to identify biologically relevant CD4+ epitopes and suggests CD4+ T cells are active participants in driving HIV evolution.

  19. Acceleration response spectrum for prediction of structural vibration due to individual bouncing

    Science.gov (United States)

    Chen, Jun; Wang, Lei; Racic, Vitomir; Lou, Jiayue

    2016-08-01

    This study is designed to develop an acceleration response spectrum that can be used in vibration serviceability assessment of civil engineering structures, such as floors and grandstands those are dynamically excited by individual bouncing. The spectrum is derived from numerical simulations and statistical analysis of acceleration responses of a single degree of freedom system with variable natural frequency and damping under a large number of experimentally measured individual bouncing loads. Its mathematical representation is fit for fast yet reliable application in design practice and is comprised of three equations that describe three distinct frequency regions observed in the actual data: the first resonant plateau (2-3.5 Hz), the second resonant plateau (4-7 Hz) and a descension region (7-15 Hz). Finally, this paper verifies the proposed response spectrum approach to predict structural vibration by direct comparison against numerical simulations and experimental results.

  20. Forward and Inverse Modelling Approaches for Prediction of Light Stimulus from Electrophysiological Response in Plants

    CERN Document Server

    Chatterjee, Shre Kumar; Das, Saptarshi; Manzella, Veronica; Vitaletti, Andrea; Masi, Elisa; Santopolo, Luisa; Mancuso, Stefano; Maharatna, Koushik

    2014-01-01

    In this paper, system identification approach has been adopted to develop a novel dynamical model for describing the relationship between light as an environmental stimulus and the electrical response as the measured output for a bay leaf (Laurus nobilis) plant. More specifically, the target is to predict the characteristics of the input light stimulus (in terms of on-off timing, duration and intensity) from the measured electrical response - leading to an inverse problem. We explored two major classes of system estimators to develop dynamical models - linear and nonlinear - and their several variants for establishing a forward and also an inverse relationship between the light stimulus and plant electrical response. The best class of models are given by the Nonlinear Hammerstein-Wiener (NLHW) estimator showing good data fitting results over other linear and nonlinear estimators in a statistical sense. Consequently, a few set of models using different functional variants of NLHW has been developed and their a...

  1. Seismic Hazard Assessment in Site Evaluation for Nuclear Installations: Ground Motion Prediction Equations and Site Response

    International Nuclear Information System (INIS)

    The objective of this publication is to provide the state-of-the-art practice and detailed technical elements related to ground motion evaluation by ground motion prediction equations (GMPEs) and site response in the context of seismic hazard assessments as recommended in IAEA Safety Standards Series No. SSG-9, Seismic Hazards in Site Evaluation for Nuclear Installations. The publication includes the basics of GMPEs, ground motion simulation, selection and adjustment of GMPEs, site characterization, and modelling of site response in order to improve seismic hazard assessment. The text aims at delineating the most important aspects of these topics (including current practices, criticalities and open problems) within a coherent framework. In particular, attention has been devoted to filling conceptual gaps. It is written as a reference text for trained users who are responsible for planning preparatory seismic hazard analyses for siting of all nuclear installations and/or providing constraints for anti-seismic design and retrofitting of existing structures

  2. A computer program for predicting nonlinear uniaxial material responses using viscoplastic models

    Science.gov (United States)

    Chang, T. Y.; Thompson, R. L.

    1984-01-01

    A computer program was developed for predicting nonlinear uniaxial material responses using viscoplastic constitutive models. Four specific models, i.e., those due to Miller, Walker, Krieg-Swearengen-Rhode, and Robinson, are included. Any other unified model is easily implemented into the program in the form of subroutines. Analysis features include stress-strain cycling, creep response, stress relaxation, thermomechanical fatigue loop, or any combination of these responses. An outline is given on the theoretical background of uniaxial constitutive models, analysis procedure, and numerical integration methods for solving the nonlinear constitutive equations. In addition, a discussion on the computer program implementation is also given. Finally, seven numerical examples are included to demonstrate the versatility of the computer program developed.

  3. Predicting Response to Neoadjuvant Chemotherapy with PET Imaging Using Convolutional Neural Networks.

    Directory of Open Access Journals (Sweden)

    Petros-Pavlos Ypsilantis

    Full Text Available Imaging of cancer with 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET has become a standard component of diagnosis and staging in oncology, and is becoming more important as a quantitative monitor of individual response to therapy. In this article we investigate the challenging problem of predicting a patient's response to neoadjuvant chemotherapy from a single 18F-FDG PET scan taken prior to treatment. We take a "radiomics" approach whereby a large amount of quantitative features is automatically extracted from pretherapy PET images in order to build a comprehensive quantification of the tumor phenotype. While the dominant methodology relies on hand-crafted texture features, we explore the potential of automatically learning low- to high-level features directly from PET scans. We report on a study that compares the performance of two competing radiomics strategies: an approach based on state-of-the-art statistical classifiers using over 100 quantitative imaging descriptors, including texture features as well as standardized uptake values, and a convolutional neural network, 3S-CNN, trained directly from PET scans by taking sets of adjacent intra-tumor slices. Our experimental results, based on a sample of 107 patients with esophageal cancer, provide initial evidence that convolutional neural networks have the potential to extract PET imaging representations that are highly predictive of response to therapy. On this dataset, 3S-CNN achieves an average 80.7% sensitivity and 81.6% specificity in predicting non-responders, and outperforms other competing predictive models.

  4. Predicting Response to Neoadjuvant Chemotherapy with PET Imaging Using Convolutional Neural Networks.

    Science.gov (United States)

    Ypsilantis, Petros-Pavlos; Siddique, Musib; Sohn, Hyon-Mok; Davies, Andrew; Cook, Gary; Goh, Vicky; Montana, Giovanni

    2015-01-01

    Imaging of cancer with 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) has become a standard component of diagnosis and staging in oncology, and is becoming more important as a quantitative monitor of individual response to therapy. In this article we investigate the challenging problem of predicting a patient's response to neoadjuvant chemotherapy from a single 18F-FDG PET scan taken prior to treatment. We take a "radiomics" approach whereby a large amount of quantitative features is automatically extracted from pretherapy PET images in order to build a comprehensive quantification of the tumor phenotype. While the dominant methodology relies on hand-crafted texture features, we explore the potential of automatically learning low- to high-level features directly from PET scans. We report on a study that compares the performance of two competing radiomics strategies: an approach based on state-of-the-art statistical classifiers using over 100 quantitative imaging descriptors, including texture features as well as standardized uptake values, and a convolutional neural network, 3S-CNN, trained directly from PET scans by taking sets of adjacent intra-tumor slices. Our experimental results, based on a sample of 107 patients with esophageal cancer, provide initial evidence that convolutional neural networks have the potential to extract PET imaging representations that are highly predictive of response to therapy. On this dataset, 3S-CNN achieves an average 80.7% sensitivity and 81.6% specificity in predicting non-responders, and outperforms other competing predictive models.

  5. Predicting Climate Change Using Response Theory: Global Averages and Spatial Patterns

    Science.gov (United States)

    Lucarini, Valerio; Ragone, Francesco; Lunkeit, Frank

    2016-04-01

    The provision of accurate methods for predicting the climate response to anthropogenic and natural forcings is a key contemporary scientific challenge. Using a simplified and efficient open-source general circulation model of the atmosphere featuring O(10^5 ) degrees of freedom, we show how it is possible to approach such a problem using nonequilibrium statistical mechanics. Response theory allows one to practically compute the time-dependent measure supported on the pullback attractor of the climate system, whose dynamics is non-autonomous as a result of time-dependent forcings. We propose a simple yet efficient method for predicting—at any lead time and in an ensemble sense—the change in climate properties resulting from increase in the concentration of CO_2 using test perturbation model runs. We assess strengths and limitations of the response theory in predicting the changes in the globally averaged values of surface temperature and of the yearly total precipitation, as well as in their spatial patterns. The quality of the predictions obtained for the surface temperature fields is rather good, while in the case of precipitation a good skill is observed only for the global average. We also show how it is possible to define accurately concepts like the inertia of the climate system or to predict when climate change is detectable given a scenario of forcing. Our analysis can be extended for dealing with more complex portfolios of forcings and can be adapted to treat, in principle, any climate observable. Our conclusion is that climate change is indeed a problem that can be effectively seen through a statistical mechanical lens, and that there is great potential for optimizing the current coordinated modelling exercises run for the preparation of the subsequent reports of the Intergovernmental Panel for Climate Change.

  6. Analysis for neural response telemetry in the patients with cochlear nerve canal stenosis during cochlear implantation surgery%蜗神经管狭窄患者耳蜗植入术中神经反应测试分析

    Institute of Scientific and Technical Information of China (English)

    王林娥; 张汝祥; 韩曙光; 王伟; 张道行

    2012-01-01

    Objective To report preoperational imaging and intraoperative neural response telemetry results of patients with cochlear nerve canal stenosis. Methods Retrospective analyzed clinical data, including imaging data and intraoperative neural response telemetry results of 7 cases with cochlear nerve canal stenosis in our hospital. Results The temporal bone CT of 7 cases showed different levels cochlear nerve canal stenosis; only one electrode can elicit electrically evoked auditory nerve compound action potential waveform in 1 case during intraoperative neural response telemetry. Two electrodes can't elicit typical electrically evoked auditory nerve compound action potential waveform in 1 case during intraoperative neural response telemetry. Conclusion Not all electrodes can elicit electrically evoked auditory nerve compound action potential waveform during intraoperative neural response test in patients with cochlear nerve canal stenosis. All the patients received benefits in hearing and speech after cochlear implantation surgery. Cochlear nerve canal stenosis may be a subtype of cochlear dysplasia.%目的 报告蜗神经管狭窄患者人工耳蜗植入术前影像学资料及术中神经反应测试结果.方法 回顾分析我院7例蜗神经管狭窄患者临床资料,包括影像学资料及术中神经反应测试结果.结果 7例患者术耳人工耳蜗植入术前颞骨薄层CT示不同程度的蜗神经管狭窄;术中神经反应测试1例患者仅1个电极可引出电诱发听神经复合动作电位波形,1例患者2个电极波形分化不良.结论 蜗神经管狭窄患者术中神经反应测试并非全部电极可以引出,术后听觉言语康复效果尚可.蜗神经管狭窄可能是耳蜗发育不良的一种亚型.

  7. A fundamental model of mistuning for system identification and forced response prediction

    Science.gov (United States)

    Feiner, Drew M.

    The vibratory response of a turbine blade is very sensitive to small changes in the blade properties. Therefore, the variations that come from the manufacturing process and wear can significantly increase a blade's vibratory stress at resonance. This phenomenon, referred to as mistuning, can cause blades in a gas turbine engine to fail from high cycle fatigue. A new reduced order model of mistuned bladed disk vibration is presented. This new approach is shown to accurately represent the response of real turbine geometries when only a single family of modes is excited. Yet its mathematical form is even simpler than that of a mass-spring model. Because it requires only minimal input data, this model is much easier to use than previous reduced order methods. Furthermore, its simplicity allows the fundamental parameters that control mistuning to be readily identified. This model is then used to develop a set of analysis tools to assess the mistuning in an engine component and predict its vibratory response under rotating conditions. These tools include a completely experimental method of system identification which uses vibratory response measurements of the bladed disk system as a whole to infer its mistuning. As a system-based method, this approach is particularly well suited to integrally bladed rotors, whose blades cannot be removed for individual testing. Next, an analytical method is developed to adjust mistuning for the effects of centrifugal stiffening. The approach allows mistuning measured from a stationary rotor to be used to predict the part's forced response under rotating conditions. Finally, the system identification method is extended to allow forced response measurements from a rotating test to be used as input. The mistuning measured through this approach will reflect all effects present during the operating conditions. One particular advantage of this method is that it can capture the effect of centrifugal loading on the mistuning of conventionally

  8. Can personality traits and gender predict the response to morphine? An experimental cold pain study.

    Science.gov (United States)

    Pud, Dorit; Yarnitsky, David; Sprecher, Elliot; Rogowski, Zeev; Adler, Rivka; Eisenberg, Elon

    2006-02-01

    The aim of the present study was to examine the possible role of personality traits, in accordance with Cloninger's theory, and gender, in the variability of responsiveness to opioids. Specifically, it was intended to test whether or not the three personality dimensions - harm avoidance (HA), reward dependence (RD) and novelty seeking (NS) - as suggested by Cloninger, can predict inter-personal differences in responsiveness to morphine after exposure to experimental cold pain. Thirty-four healthy volunteers (15 females, 19 males) were given the cold pressor test (CPT). Pain threshold, tolerance, and magnitude (VAS) were measured before and after (six measures, 30 min apart) the administration of either 0.5 mg/kg oral morphine sulphate (n=21) or 0.33 mg/kg oral active placebo (diphenhydramine) (n=13) in a randomized, double blind design. Assessment of the three personality traits, according to Cloninger's Tridimensional Personality Questionnaire, was performed before the CPT. A high HA score (but not RD, NS, or baseline values of the three pain parameters) predicted a significantly larger pain relief following the administration of morphine sulphate (but not of the placebo). Women exhibited a larger response in response to both treatments, as indicated by a significantly increased threshold and tolerance following morphine sulphate as well as significantly increased tolerance and decreased magnitude following placebo administration. The present study confirms the existence of individual differences in response to analgesic treatment. It suggests that high HA personality trait is associated with better responsiveness to morphine treatment, and that females respond better than men to both morphine and placebo. PMID:16310713

  9. Spatial properties of objects predict patterns of neural response in the ventral visual pathway.

    Science.gov (United States)

    Watson, David M; Young, Andrew W; Andrews, Timothy J

    2016-02-01

    Neuroimaging studies have revealed topographically organised patterns of response to different objects in the ventral visual pathway. These patterns are thought to be based on the form of the object. However, it is not clear what dimensions of object form are important. Here, we determined the extent to which spatial properties (energy across the image) could explain patterns of response in these regions. We compared patterns of fMRI response to images from different object categories presented at different retinal sizes. Although distinct neural patterns were evident to different object categories, changing the size (and thus the spatial properties) of the images had a significant effect on these patterns. Next, we used a computational approach to determine whether more fine-grained differences in the spatial properties can explain the patterns of neural response to different objects. We found that the spatial properties of the image were able to predict patterns of neural response, even when categorical factors were removed from the analysis. We also found that the effect of spatial properties on the patterns of response varies across the ventral visual pathway. These results show how spatial properties can be an important organising principle in the topography of the ventral visual pathway. PMID:26619786

  10. Quantifying bile acid malabsorption helps predict response and tailor sequestrant therapy.

    Science.gov (United States)

    Orekoya, Oluwafikunayo; McLaughlin, John; Leitao, Eugenia; Johns, Wendy; Lal, Simon; Paine, Peter

    2015-06-01

    Although recognised as a cause of chronic diarrhoea for over forty years, diagnostic tests and treatments for bile acid malabsorption (BAM) remain controversial. Recent National Institute for Health and Care Excellence (NICE) guidelines highlighted the lack of evidence in the field, and called for further research. This retrospective study explores the BAM subtype and severity, the use and response to bile acid sequestrants (BAS) and the prevalence of abnormal colonic histology. 264 selenium-75-labelled homocholic acid conjugated taurine (SeHCAT)-tested patient records were reviewed and the severity and subtype of BAM, presence of colonic histopathology and response to BAS were recorded. 53% of patients tested had BAM, with type-2 BAM in 45% of patients with presumed irritable bowel syndrome. Colonic histological abnormalities were similar overall between patients with (29%) or without (23%) BAM (p = 0.46) and between BAM subtypes, with no significant presence of inflammatory changes. 63% of patients with BAM had a successful BAS response which showed a trend to decreased response with reduced severity. Colestyramine was unsuccessful in 44% (38/87) and 45% of these (17/38) were related to medication intolerance, despite a positive SeHCAT. 47% (7/15) of colestyramine failures had a successful colesevelam response. No patient reported colesevelam intolerance. Quantifying severity of BAM appears to be useful in predicting BAS response. Colesevelam was better tolerated than colestyramine and showed some efficacy in colestyramine failures. Colestyramine failure should not be used to exclude BAM. Colonic histology is of no relevance.

  11. Assessing conservation relevance of organism-environment relations using predicted changes in response variables

    Science.gov (United States)

    Gutzwiller, Kevin J.; Barrow, Wylie C.; White, Joseph D.; Johnson-Randall, Lori; Cade, Brian S.; Zygo, Lisa M.

    2010-01-01

    1. Organism–environment models are used widely in conservation. The degree to which they are useful for informing conservation decisions – the conservation relevance of these relations – is important because lack of relevance may lead to misapplication of scarce conservation resources or failure to resolve important conservation dilemmas. Even when models perform well based on model fit and predictive ability, conservation relevance of associations may not be clear without also knowing the magnitude and variability of predicted changes in response variables. 2. We introduce a method for evaluating the conservation relevance of organism–environment relations that employs confidence intervals for predicted changes in response variables. The confidence intervals are compared to a preselected magnitude of change that marks a threshold (trigger) for conservation action. To demonstrate the approach, we used a case study from the Chihuahuan Desert involving relations between avian richness and broad-scale patterns of shrubland. We considered relations for three winters and two spatial extents (1- and 2-km-radius areas) and compared predicted changes in richness to three thresholds (10%, 20% and 30% change). For each threshold, we examined 48 relations. 3. The method identified seven, four and zero conservation-relevant changes in mean richness for the 10%, 20% and 30% thresholds respectively. These changes were associated with major (20%) changes in shrubland cover, mean patch size, the coefficient of variation for patch size, or edge density but not with major changes in shrubland patch density. The relative rarity of conservation-relevant changes indicated that, overall, the relations had little practical value for informing conservation decisions about avian richness. 4. The approach we illustrate is appropriate for various response and predictor variables measured at any temporal or spatial scale. The method is broadly applicable across ecological

  12. Electrophysiological Indices of Response Inhibition in a Go/NoGo Task Predict Self-Control in a Social Context

    OpenAIRE

    Kyle Nash; Bastian Schiller; Gianotti, Lorena R. R.; Thomas Baumgartner; Daria Knoch

    2013-01-01

    Recent research demonstrates that response inhibition-a core executive function-may subserve self-regulation and self-control. However, it is unclear whether response inhibition also predicts self-control in the multifaceted, high-level phenomena of social decision-making. Here we examined whether electrophysiological indices of response inhibition would predict self-control in a social context. Electroencephalography was recorded as participants completed a widely used Go/NoGo task (the cued...

  13. Prediction and Validation of Promoters Involved in the Abscisic Acid Response in Physcomitrella patens

    Institute of Scientific and Technical Information of China (English)

    Gerrit Timmerhaus; Sebastian T.Hanke; Karl Buchta; Stefan A. Rensing

    2011-01-01

    Detection of cis-regulatory elements, such as transcription factor binding sites (TFBS), through utilization of ortholog conservation is possible only if genomic data from closely related organisms are available. An alternative ap-proach is the detection of TFBS based on their overrepresentation in promoters of co-regulated genes. However, this ap-proach usually suffers from a high rate of false-positive prediction. Here, we have conducted a case study using promoters of genes known to be strongly induced by the phytohormone abscisic acid (ABA)in the model plant Physcornitrella patens,a moss. Putative TFBS were detected using three de novo motif detection tools in a strict consensus approach. The resulting motifs were validated using data from microarray expression profiling and were able to predict ABA-induced genes with high specificity (90.48%)at mediocre sensitivity (33.33%). In addition, 27 genes predicted to contain ABA-responsive TFBS were validated using real-time PCR. Here, a total of 37% of the genes could be shown to be induced upon ABA treatment,while 70% were found to be regulated by ABA. We conclude that the consensus approach for motif detection using co-regulation information can be used to identify genes that are regulated under a given stimulus. In terms of evolution, we find that the ABA response has apparently been conserved since the first land plants on the level of families involved in transcriptional regulation.

  14. TFF3 is a valuable predictive biomarker of endocrine response in metastatic breast cancer.

    Science.gov (United States)

    May, Felicity E B; Westley, Bruce R

    2015-06-01

    The stratification of breast cancer patients for endocrine therapies by oestrogen or progesterone receptor expression is effective but imperfect. The present study aims were to validate microarray studies that demonstrate TFF3 regulation by oestrogen and its association with oestrogen receptors in breast cancer, to evaluate TFF3 as a biomarker of endocrine response, and to investigate TFF3 function. Microarray data were validated by quantitative RT-PCR and northern and western transfer analyses. TFF3 was induced by oestrogen, and its induction was inhibited by antioestrogens, tamoxifen, 4-hydroxytamoxifen and fulvestrant in oestrogen-responsive breast cancer cells. The expression of TFF3 mRNA was associated with oestrogen receptor mRNA in breast tumours (Pearson's coefficient=0.762, P=0.000). Monoclonal antibodies raised against the TFF3 protein detected TFF3 by immunohistochemistry in oesophageal submucosal glands, intestinal goblet and neuroendocrine cells, Barrett's metaplasia and intestinal metaplasia. TFF3 protein expression was associated with oestrogen receptor, progesterone receptor and TFF1 expression in malignant breast cells. TFF3 is a specific and sensitive predictive biomarker of response to endocrine therapy, degree of response and duration of response in unstratified metastatic breast cancer patients (P=0.000, P=0.002 and P=0.002 respectively). Multivariate binary logistic regression analysis demonstrated that TFF3 is an independent biomarker of endocrine response and degree of response, and this was confirmed in a validation cohort. TFF3 stimulated migration and invasion of breast cancer cells. In conclusion, TFF3 expression is associated with response to endocrine therapy, and outperforms oestrogen receptor, progesterone receptor and TFF1 as an independent biomarker, possibly because it mediates the malign effects of oestrogen on invasion and metastasis.

  15. Predictive computational modeling of the mucosal immune responses during Helicobacter pylori infection.

    Directory of Open Access Journals (Sweden)

    Adria Carbo

    Full Text Available T helper (Th cells play a major role in the immune response and pathology at the gastric mucosa during Helicobacter pylori infection. There is a limited mechanistic understanding regarding the contributions of CD4+ T cell subsets to gastritis development during H. pylori colonization. We used two computational approaches: ordinary differential equation (ODE-based and agent-based modeling (ABM to study the mechanisms underlying cellular immune responses to H. pylori and how CD4+ T cell subsets influenced initiation, progression and outcome of disease. To calibrate the model, in vivo experimentation was performed by infecting C57BL/6 mice intragastrically with H. pylori and assaying immune cell subsets in the stomach and gastric lymph nodes (GLN on days 0, 7, 14, 30 and 60 post-infection. Our computational model reproduced the dynamics of effector and regulatory pathways in the gastric lamina propria (LP in silico. Simulation results show the induction of a Th17 response and a dominant Th1 response, together with a regulatory response characterized by high levels of mucosal Treg cells. We also investigated the potential role of peroxisome proliferator-activated receptor γ (PPARγ activation on the modulation of host responses to H. pylori by using loss-of-function approaches. Specifically, in silico results showed a predominance of Th1 and Th17 cells in the stomach of the cell-specific PPARγ knockout system when compared to the wild-type simulation. Spatio-temporal, object-oriented ABM approaches suggested similar dynamics in induction of host responses showing analogous T cell distributions to ODE modeling and facilitated tracking lesion formation. In addition, sensitivity analysis predicted a crucial contribution of Th1 and Th17 effector responses as mediators of histopathological changes in the gastric mucosa during chronic stages of infection, which were experimentally validated in mice. These integrated immunoinformatics approaches

  16. Response surface and artificial neural network prediction model and optimization for surface roughness in machining

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Sahoo

    2015-04-01

    Full Text Available The present paper deals with the development of prediction model using response surface methodology and artificial neural network and optimizes the process parameter using 3D surface plot. The experiment has been conducted using coated carbide insert in machining AISI 1040 steel under dry environment. The coefficient of determination value for RSM model is found to be high (R2 = 0.99 close to unity. It indicates the goodness of fit for the model and high significance of the model. The percentage of error for RSM model is found to be only from -2.63 to 2.47. The maximum error between ANN model and experimental lies between -1.27 and 0.02 %, which is significantly less than the RSM model. Hence, both the proposed RSM and ANN prediction model sufficiently predict the surface roughness, accurately. However, ANN prediction model seems to be better compared with RSM model. From the 3D surface plots, the optimal parametric combination for the lowest surface roughness is d1-f1-v3 i.e. depth of cut of 0.1 mm, feed of 0.04 mm/rev and cutting speed of 260 m/min respectively.

  17. Crowdsourced assessment of common genetic contribution to predicting anti-TNF treatment response in rheumatoid arthritis

    Science.gov (United States)

    Sieberts, Solveig K.; Zhu, Fan; García-García, Javier; Stahl, Eli; Pratap, Abhishek; Pandey, Gaurav; Pappas, Dimitrios; Aguilar, Daniel; Anton, Bernat; Bonet, Jaume; Eksi, Ridvan; Fornés, Oriol; Guney, Emre; Li, Hongdong; Marín, Manuel Alejandro; Panwar, Bharat; Planas-Iglesias, Joan; Poglayen, Daniel; Cui, Jing; Falcao, Andre O.; Suver, Christine; Hoff, Bruce; Balagurusamy, Venkat S. K.; Dillenberger, Donna; Neto, Elias Chaibub; Norman, Thea; Aittokallio, Tero; Ammad-ud-din, Muhammad; Azencott, Chloe-Agathe; Bellón, Víctor; Boeva, Valentina; Bunte, Kerstin; Chheda, Himanshu; Cheng, Lu; Corander, Jukka; Dumontier, Michel; Goldenberg, Anna; Gopalacharyulu, Peddinti; Hajiloo, Mohsen; Hidru, Daniel; Jaiswal, Alok; Kaski, Samuel; Khalfaoui, Beyrem; Khan, Suleiman Ali; Kramer, Eric R.; Marttinen, Pekka; Mezlini, Aziz M.; Molparia, Bhuvan; Pirinen, Matti; Saarela, Janna; Samwald, Matthias; Stoven, Véronique; Tang, Hao; Tang, Jing; Torkamani, Ali; Vert, Jean-Phillipe; Wang, Bo; Wang, Tao; Wennerberg, Krister; Wineinger, Nathan E.; Xiao, Guanghua; Xie, Yang; Yeung, Rae; Zhan, Xiaowei; Zhao, Cheng; Calaza, Manuel; Elmarakeby, Haitham; Heath, Lenwood S.; Long, Quan; Moore, Jonathan D.; Opiyo, Stephen Obol; Savage, Richard S.; Zhu, Jun; Greenberg, Jeff; Kremer, Joel; Michaud, Kaleb; Barton, Anne; Coenen, Marieke; Mariette, Xavier; Miceli, Corinne; Shadick, Nancy; Weinblatt, Michael; de Vries, Niek; Tak, Paul P.; Gerlag, Danielle; Huizinga, Tom W. J.; Kurreeman, Fina; Allaart, Cornelia F.; Louis Bridges Jr., S.; Criswell, Lindsey; Moreland, Larry; Klareskog, Lars; Saevarsdottir, Saedis; Padyukov, Leonid; Gregersen, Peter K.; Friend, Stephen; Plenge, Robert; Stolovitzky, Gustavo; Oliva, Baldo; Guan, Yuanfang; Mangravite, Lara M.

    2016-01-01

    Rheumatoid arthritis (RA) affects millions world-wide. While anti-TNF treatment is widely used to reduce disease progression, treatment fails in ∼one-third of patients. No biomarker currently exists that identifies non-responders before treatment. A rigorous community-based assessment of the utility of SNP data for predicting anti-TNF treatment efficacy in RA patients was performed in the context of a DREAM Challenge (http://www.synapse.org/RA_Challenge). An open challenge framework enabled the comparative evaluation of predictions developed by 73 research groups using the most comprehensive available data and covering a wide range of state-of-the-art modelling methodologies. Despite a significant genetic heritability estimate of treatment non-response trait (h2=0.18, P value=0.02), no significant genetic contribution to prediction accuracy is observed. Results formally confirm the expectations of the rheumatology community that SNP information does not significantly improve predictive performance relative to standard clinical traits, thereby justifying a refocusing of future efforts on collection of other data. PMID:27549343

  18. Crowdsourced assessment of common genetic contribution to predicting anti-TNF treatment response in rheumatoid arthritis.

    Science.gov (United States)

    Sieberts, Solveig K; Zhu, Fan; García-García, Javier; Stahl, Eli; Pratap, Abhishek; Pandey, Gaurav; Pappas, Dimitrios; Aguilar, Daniel; Anton, Bernat; Bonet, Jaume; Eksi, Ridvan; Fornés, Oriol; Guney, Emre; Li, Hongdong; Marín, Manuel Alejandro; Panwar, Bharat; Planas-Iglesias, Joan; Poglayen, Daniel; Cui, Jing; Falcao, Andre O; Suver, Christine; Hoff, Bruce; Balagurusamy, Venkat S K; Dillenberger, Donna; Neto, Elias Chaibub; Norman, Thea; Aittokallio, Tero; Ammad-Ud-Din, Muhammad; Azencott, Chloe-Agathe; Bellón, Víctor; Boeva, Valentina; Bunte, Kerstin; Chheda, Himanshu; Cheng, Lu; Corander, Jukka; Dumontier, Michel; Goldenberg, Anna; Gopalacharyulu, Peddinti; Hajiloo, Mohsen; Hidru, Daniel; Jaiswal, Alok; Kaski, Samuel; Khalfaoui, Beyrem; Khan, Suleiman Ali; Kramer, Eric R; Marttinen, Pekka; Mezlini, Aziz M; Molparia, Bhuvan; Pirinen, Matti; Saarela, Janna; Samwald, Matthias; Stoven, Véronique; Tang, Hao; Tang, Jing; Torkamani, Ali; Vert, Jean-Phillipe; Wang, Bo; Wang, Tao; Wennerberg, Krister; Wineinger, Nathan E; Xiao, Guanghua; Xie, Yang; Yeung, Rae; Zhan, Xiaowei; Zhao, Cheng; Greenberg, Jeff; Kremer, Joel; Michaud, Kaleb; Barton, Anne; Coenen, Marieke; Mariette, Xavier; Miceli, Corinne; Shadick, Nancy; Weinblatt, Michael; de Vries, Niek; Tak, Paul P; Gerlag, Danielle; Huizinga, Tom W J; Kurreeman, Fina; Allaart, Cornelia F; Louis Bridges, S; Criswell, Lindsey; Moreland, Larry; Klareskog, Lars; Saevarsdottir, Saedis; Padyukov, Leonid; Gregersen, Peter K; Friend, Stephen; Plenge, Robert; Stolovitzky, Gustavo; Oliva, Baldo; Guan, Yuanfang; Mangravite, Lara M; Bridges, S Louis; Criswell, Lindsey; Moreland, Larry; Klareskog, Lars; Saevarsdottir, Saedis; Padyukov, Leonid; Gregersen, Peter K; Friend, Stephen; Plenge, Robert; Stolovitzky, Gustavo; Oliva, Baldo; Guan, Yuanfang; Mangravite, Lara M

    2016-01-01

    Rheumatoid arthritis (RA) affects millions world-wide. While anti-TNF treatment is widely used to reduce disease progression, treatment fails in ∼one-third of patients. No biomarker currently exists that identifies non-responders before treatment. A rigorous community-based assessment of the utility of SNP data for predicting anti-TNF treatment efficacy in RA patients was performed in the context of a DREAM Challenge (http://www.synapse.org/RA_Challenge). An open challenge framework enabled the comparative evaluation of predictions developed by 73 research groups using the most comprehensive available data and covering a wide range of state-of-the-art modelling methodologies. Despite a significant genetic heritability estimate of treatment non-response trait (h(2)=0.18, P value=0.02), no significant genetic contribution to prediction accuracy is observed. Results formally confirm the expectations of the rheumatology community that SNP information does not significantly improve predictive performance relative to standard clinical traits, thereby justifying a refocusing of future efforts on collection of other data. PMID:27549343

  19. Dissociation predicts treatment response in eye-movement desensitization and reprocessing for posttraumatic stress disorder.

    Science.gov (United States)

    Bae, Hwallip; Kim, Daeho; Park, Yong Chon

    2016-01-01

    Using clinical data from a specialized trauma clinic, this study investigated pretreatment clinical factors predicting response to eye-movement desensitization and reprocessing (EMDR) among adult patients diagnosed with posttraumatic stress disorder (PTSD). Participants were evaluated using the Clinician-Administered PTSD Scale (CAPS), the Symptom Checklist-90-Revised, the Beck Depression Inventory, and the Dissociative Experiences Scale before treatment and were reassessed using the CAPS after treatment and at 6-month follow-up. A total of 69 patients underwent an average of 4 sessions of EMDR, and 60 (87%) completed the posttreatment evaluation, including 8 participants who terminated treatment prematurely. Intent-to-treat analysis revealed that 39 (65%) of the 60 patients were classified as responders and 21 (35%) as nonresponders when response was defined as more than a 30% decrease in total CAPS score. The nonresponders had higher levels of dissociation (depersonalization and derealization) and numbing symptoms, but other PTSD symptoms, such as avoidance, hyperarousal, and intrusion, were not significantly different. The number of psychiatric comorbidities was also associated with treatment nonresponse. The final logistic regression model yielded 2 significant variables: dissociation (p < .001) and more than 2 comorbidities compared to none (p < .05). These results indicate that complex symptom patterns in PTSD may predict treatment response and support the inclusion of the dissociative subtype of PTSD in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. PMID:26156867

  20. Does salivary gland scintigraphy predict response to pilocarpine in patients with post-radiotherapy xerostomia?

    International Nuclear Information System (INIS)

    This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine. (orig.)

  1. Does salivary gland scintigraphy predict response to pilocarpine in patients with post-radiotherapy xerostomia?

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.A.; Cowan, R.A.; Slevin, N.J.; Allan, E.; Gupta, N.K. [Department of Clinical Oncology, Christie Hospital, Manchester (United Kingdom); Owens, S.E.; Jeans, S.P.; Roberts, J.K.; Hillel, P.G. [North Western Medical Physics, Christie Hospital, Manchester (United Kingdom); Collins, C.D. [Department of Radiology, Christie Hospital, Manchester (United Kingdom)

    1999-03-01

    This study was undertaken to determine whether standard salivary gland scintigraphy may be used for the objective assessment of salivary gland sialogogues, in particular oral pilocarpine, in the treatment of post-radiotherapy xerostomia. Nine patients, with xerostomia following radiotherapy to the head and neck region underwent salivary gland scintigraphy with technetium-99m pertechnetate (40 MBq) both before and following 1 month of oral pilocarpine (5 mg tds). For each scan, the percentage uptake in the first 14 min, the peak uptake, time to peak uptake and the percentage of activity excreted following lemon juice stimulation were calculated. The results were correlated with the subjective response as assessed by questionnaire and visual analogue scale. We found no correlation between subjective response and any of the four scan parameters analysed. We could not identify any parameter that predicted those patients who would respond to pilocarpine. In addition, only one parameter, the percentage of activity excreted following stimulation, correlated with previous dose of radiotherapy to the gland. In conclusion, in this study salivary gland scintigraphy did not appear to correlate with or predict response to oral pilocarpine. However, future studies might consider performing salivary gland scintigraphy prior to radiotherapy as well as at differing time points following the commencement of pilocarpine. (orig.) With 6 figs., 1 tab., 20 refs.

  2. Hemodynamic Changes during a Deep Inspiration Maneuver Predict Fluid Responsiveness in Spontaneously Breathing Patients

    Directory of Open Access Journals (Sweden)

    Sébastien Préau

    2012-01-01

    Full Text Available Objective. We hypothesized that the hemodynamic response to a deep inspiration maneuver (DIM indicates fluid responsiveness in spontaneously breathing (SB patients. Design. Prospective study. Setting. ICU of a general hospital. Patients. Consecutive nonintubated patients without mechanical ventilation, considered for volume expansion (VE. Intervention. We assessed hemodynamic status at baseline and after VE. Measurements and Main Results. We measured radial pulse pressure (PP using an arterial catheter and peak velocity of femoral artery flow (VF using continuous Doppler. Changes in PP and VF induced by a DIM (ΔPPdim and ΔVFdim were calculated in 23 patients. ΔPPdim and ΔVFdim ≥12% predicted responders to VE with sensitivity of 90% and specificity of 100%. Conclusions. In a restricted population of SB patients with severe sepsis or acute pancreatitis, ΔPPdim and ΔVFdim are accurate indices for predicting fluid responsiveness. These results should be confirmed in a larger population before validating their use in current practice.

  3. Prediction of response to radiotherapy in the treatment of esophageal cancer using stem cell markers

    International Nuclear Information System (INIS)

    Background and purpose: In this study, we investigated whether cancer stem cell marker expressing cells can be identified that predict for the response of esophageal cancer (EC) to CRT. Materials and methods: EC cell-lines OE-33 and OE-21 were used to assess in vitro, stem cell activity, proliferative capacity and radiation response. Xenograft tumors were generated using NOD/SCID mice to assess in vivo proliferative capacity and tumor hypoxia. Archival and fresh EC biopsy tissue was used to confirm our in vitro and in vivo results. Results: We showed that the CD44+/CD24− subpopulation of EC cells exerts a higher proliferation rate and sphere forming potential and is more radioresistant in vitro, when compared to unselected or CD44+/CD24+ cells. Moreover, CD44+/CD24− cells formed xenograft tumors faster and were often located in hypoxic tumor areas. In a study of archival pre-neoadjuvant CRT biopsy material from EC adenocarcinoma patients (N = 27), this population could only be identified in 50% (9/18) of reduced-responders to neoadjuvant CRT, but never (0/9) in the complete responders (P = 0.009). Conclusion: These results warrant further investigation into the possible clinical benefit of CD44+/CD24− as a predictive marker in EC patients for the response to chemoradiation

  4. Circadian gene expression predicts patient response to neoadjuvant chemoradiation therapy for rectal cancer.

    Science.gov (United States)

    Lu, Haijie; Chu, Qiqi; Xie, Guojiang; Han, Hao; Chen, Zheng; Xu, Benhua; Yue, Zhicao

    2015-01-01

    Preoperative neoadjuvant chemoradiation therapy may be useful in patients with operable rectal cancer, but treatment responses are variable. We examined whether expression levels of circadian clock genes could be used as biomarkers to predict treatment response. We retrospectively analyzed clinical data from 250 patients with rectal cancer, treated with neoadjuvant chemoradiation therapy in a single institute between 2011 and 2013. Gene expression analysis (RT-PCR) was performed in tissue samples from 20 patients showing pathological complete regression (pCR) and 20 showing non-pCR. The genes analyzed included six core clock genes (Clock, Per1, Per2, Cry1, Cry2 and Bmal1) and three downstream target genes (Wee1, Chk2 and c-Myc). Patient responses were analyzed through contrast-enhanced pelvic MRI and endorectal ultrasound, and verified by histological assessment. pCR was defined histologically as an absence of tumor cells. Among the 250 included patients, 70.8% showed regression of tumor size, and 18% showed pCR. Clock, Cry2 and Per2 expressions were significantly higher in the pCR group than in the non-pCR group (PWee1 and Chk2 expression did not differ significantly between groups. Circadian genes are potential biomarkers for predicting whether a patient with rectal cancer would benefit from neoadjuvant chemoradiation therapy. PMID:26617816

  5. Agitation predicts response of depression to botulinum toxin treatment in a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Marc Axel Wollmer

    2014-03-01

    Full Text Available In a randomized, controlled trial (n=30 we showed that botulinum toxin injection to the glabellar region produces a marked improvement in the symptoms of major depression. We hypothesized that the mood-lifting effect was mediated by facial feedback mechanisms. Here we assessed if agitation, which may be associated with increased dynamic psychomotor activity of the facial musculature, can predict response to the treatment. To test this hypothesis we re-analyzed the data of the scales from our previous study on a single item basis and compared the baseline scores in the agitation item (item 9 of the Hamilton Depression Rating Scale (HAM-D between responders (n=9 and participants who did not attain response (n=6 among the recipients of onabotulinumtoxinA (n=15. Results: Responders had significantly higher item 9 scores at baseline (1.56+0.88 vs. 0.33+0.52, t(13=3.04, d=1.7, p=0.01, while no other single item of the HAM-D or the Beck Depression Inventory was associated with treatment response. The agitation score had an overall precision of 78% in predicting response in a receiver operating characteristic (ROC analysis (area under the curve, AUC=0.87. These data provide a link between response to botulinum toxin treatment with a psychomotor manifestation of depression and thereby indirect support of the proposed facial feedback mechanism of action. Moreover, it suggests that patients with agitated depression may particularly benefit from botulinum toxin treatment.

  6. Does Cognition Predict Treatment Response and Remission in Psychotherapy for Late-Life Depression?

    Science.gov (United States)

    Beaudreau, Sherry A.; Rideaux, Tiffany; O'Hara, Ruth; Arean, Patricia

    2014-01-01

    Objectives To identify cognitive predictors of geriatric depression treatment outcome. Method Older participants completed baseline measures of memory and executive function, health, and baseline and posttreatment Hamilton Depression Scales (HAM-D) in a 12-week trial comparing psychotherapies (problem-solving vs. supportive; n = 46). We examined cognitive predictors to identify treatment responders, i.e., HAM-D scores reduced by ≥50%, and remitters, i.e., posttreatment HAM-D score ≤ 10. Results Empirically-derived decision trees identified poorer performance on switching (i.e. Trails B), with a cut-score of ≥82” predicting psychotherapy responders. No other cognitive or health variables predicted psychotherapy outcomes in the decision trees. Conclusions Psychotherapies that support or improve the executive skill of switching may augment treatment response for older patients exhibiting executive dysfunction in depression. If replicated, Trails B has potential as a brief cognitive tool for clinical decision-making in geriatric depression. PMID:25441055

  7. Sexual selection predicts advancement of avian spring migration in response to climate change

    DEFF Research Database (Denmark)

    Spottiswoode, Claire N; Tøttrup, Anders P; Coppack, Timothy

    2006-01-01

    suggest that sexual selection could help to understand this variation, since early spring arrival of males is favoured by female choice. Climate change could weaken the strength of natural selection opposing sexual selection for early migration, which would predict greatest advancement in species...... with stronger female choice. We test this hypothesis comparatively by investigating the degree of long-term change in spring passage at two ringing stations in northern Europe in relation to a synthetic estimate of the strength of female choice, composed of degree of extra-pair paternity, relative testes size...... in the timing of first-arriving individuals, suggesting that selection has not only acted on protandrous males. These results suggest that sexual selection may have an impact on the responses of organisms to climate change, and knowledge of a species' mating system might help to inform attempts at predicting...

  8. Characterizing climate predictability and model response variability from multiple initial condition and multi-model ensembles

    CERN Document Server

    Kumar, Devashish

    2016-01-01

    Climate models are thought to solve boundary value problems unlike numerical weather prediction, which is an initial value problem. However, climate internal variability (CIV) is thought to be relatively important at near-term (0-30 year) prediction horizons, especially at higher resolutions. The recent availability of significant numbers of multi-model (MME) and multi-initial condition (MICE) ensembles allows for the first time a direct sensitivity analysis of CIV versus model response variability (MRV). Understanding the relative agreement and variability of MME and MICE ensembles for multiple regions, resolutions, and projection horizons is critical for focusing model improvements, diagnostics, and prognosis, as well as impacts, adaptation, and vulnerability studies. Here we find that CIV (MICE agreement) is lower (higher) than MRV (MME agreement) across all spatial resolutions and projection time horizons for both temperature and precipitation. However, CIV dominates MRV over higher latitudes generally an...

  9. Beyond the effective mass approximation: predictive theory of the nonlinear optical response of conduction electrons

    CERN Document Server

    Yu, Shukai; Talbayev, Diyar

    2016-01-01

    We present an experimental and computational study of the nonlinear optical response of conduction electrons to intense terahertz (THz) electric field. Our observations (saturable absorption and an amplitude-dependent group refractive index) can be understood on the qualitative level as the breakdown of the effective mass approximation. However, a predictive theoretical description of the nonlinearity has been missing. We propose a model based on the semiclassical electron dynamics, a realistic band structure, and the free electron Drude parameters to accurately calculate the experimental observables in InSb. Our results open a path to predictive modeling of the conduction-electron optical nonlinearity in semiconductors, metamaterials, as well as high-field effects in THz plasmonics.

  10. The effects of incidentally learned temporal and spatial predictability on response times and visual fixations during target detection and discrimination.

    Science.gov (United States)

    Beck, Melissa R; Hong, S Lee; van Lamsweerde, Amanda E; Ericson, Justin M

    2014-01-01

    Responses are quicker to predictable stimuli than if the time and place of appearance is uncertain. Studies that manipulate target predictability often involve overt cues to speed up response times. However, less is known about whether individuals will exhibit faster response times when target predictability is embedded within the inter-trial relationships. The current research examined the combined effects of spatial and temporal target predictability on reaction time (RT) and allocation of overt attention in a sustained attention task. Participants responded as quickly as possible to stimuli while their RT and eye movements were measured. Target temporal and spatial predictability were manipulated by altering the number of: 1) different time intervals between a response and the next target; and 2) possible spatial locations of the target. The effects of target predictability on target detection (Experiment 1) and target discrimination (Experiment 2) were tested. For both experiments, shorter RTs as target predictability increased across both space and time were found. In addition, the influences of spatial and temporal target predictability on RT and the overt allocation of attention were task dependent; suggesting that effective orienting of attention relies on both spatial and temporal predictability. These results indicate that stimulus predictability can be increased without overt cues and detected purely through inter-trial relationships over the course of repeated stimulus presentations.

  11. The effects of incidentally learned temporal and spatial predictability on response times and visual fixations during target detection and discrimination.

    Directory of Open Access Journals (Sweden)

    Melissa R Beck

    Full Text Available Responses are quicker to predictable stimuli than if the time and place of appearance is uncertain. Studies that manipulate target predictability often involve overt cues to speed up response times. However, less is known about whether individuals will exhibit faster response times when target predictability is embedded within the inter-trial relationships. The current research examined the combined effects of spatial and temporal target predictability on reaction time (RT and allocation of overt attention in a sustained attention task. Participants responded as quickly as possible to stimuli while their RT and eye movements were measured. Target temporal and spatial predictability were manipulated by altering the number of: 1 different time intervals between a response and the next target; and 2 possible spatial locations of the target. The effects of target predictability on target detection (Experiment 1 and target discrimination (Experiment 2 were tested. For both experiments, shorter RTs as target predictability increased across both space and time were found. In addition, the influences of spatial and temporal target predictability on RT and the overt allocation of attention were task dependent; suggesting that effective orienting of attention relies on both spatial and temporal predictability. These results indicate that stimulus predictability can be increased without overt cues and detected purely through inter-trial relationships over the course of repeated stimulus presentations.

  12. Predictive value of serum medroxyprogesterone acetate concentration for response in advanced or recurrent breast cancer.

    Science.gov (United States)

    Nishimura, R; Nagao, K; Matsuda, M; Baba, K; Matsuoka, Y; Yamashita, H; Fukuda, M; Higuchi, A; Ikeda, K

    1997-08-01

    Medroxyprogesterone acetate (MPA) is one of the most commonly prescribed drugs for endocrine therapy of metastatic breast cancer. In this study, the serum MPA concentration was measured by high-performance liquid chromatography (HPLC) and evaluated for its usefulness in predicting the response in 79 cases of advanced or recurrent breast cancers. Overall, 29 patients (37%) achieved an objective response. The response rate correlated significantly with the oestrogen receptor (ER) status (P = 0.03), proliferative activity determined by DNA polymerase alpha (P = 0.04), the disease-free interval (DFI) (P = 0.05) and the serum MPA concentration (P < 0.001). Patients with ER-positive tumours, lower proliferative activity, a longer (DFI) or a higher serum MPA concentration responded more frequently. The mean serum MPA concentration in the responders with ER-positive tumours (P = 0.01) or tumours with a lower proliferative activity (P = 0.008) were significantly lower than in cases with ER-negative tumours or tumours with a higher proliferative activity, respectively. Cases with soft tissue metastases showed responses at significantly lower MPA concentrations (P = 0.003) than those with bone or visceral metastases. Furthermore, there was a dramatic decrease in the MPA concentration when a responder with a high concentration became unresponsive to the therapy. Thus, the serum MPA concentration is a determining factor for the response to treatment. PMID:9337682

  13. High-resolution MRI predicts steroid injection response in carpal tunnel syndrome patients

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Takatoshi; Oki, Hodaka; Kinoshita, Shunsuke; Yamashita, Yoshiko; Takahashi, Hiroyuki; Hayashida, Yoshiko; Korogi, Yukunori [University of Occupational and Environmental Health School of Medicine, Department of Radiology, Kitakyushu (Japan); Oshige, Takahisa; Sakai, Akinori [University of Occupational and Environmental Health School of Medicine, Department of Orthopaedic Surgery, Kitakyushu (Japan); Matsuyama, Atsushi; Hisaoka, Masanori [University of Occupational and Environmental Health School of Medicine, Department of Pathology and Oncology, Kitakyushu (Japan)

    2014-03-15

    To correlate median nerve T2 signal and shape at the carpal tunnel with steroid injection (SI) response in carpal tunnel syndrome (CTS) patients. One hundred and sixty-three CTS wrists of 92 consecutive patients who were scheduled to undergo SI were prospectively evaluated with 3-T magnetic resonance imaging (MRI) and a nerve conduction study. All patients underwent axial high-resolution T2-weighted MRI (in-plane resolution of 0.25 x 0.25 mm). The CTS wrists were classified into three groups according to the nerve T2 signal and the flattening ratio at the hook of hamate level: group 1, high and oval; group 2, high and flat; group 3, low and flat. Clinical response to SI was evaluated at 6 months after injection. One hundred and thirteen of the 163 wrists (69.3 %) responded well to SI. The percentage of improvement was 81.7 % (49/60) in group 1, 69.9 % (51/73) in group 2, and 43.3 % (13/30) in group 3 (P < 0.01). On stepwise logistic regression analysis high-resolution MRI was the only significant independent factor for SI response in CTS patients (P < 0.01). High-resolution MRI correlates well with SI response in CTS patients and seems useful for predicting SI response. (orig.)

  14. Species differences in bumblebee immune response predict developmental success of a parasitoid fly.

    Science.gov (United States)

    Davis, Staige E; Malfi, Rosemary L; Roulston, T'ai H

    2015-08-01

    Endoparasitoids develop inside the body of a host organism and, if successful, eventually kill their host in order to reach maturity. Host species can vary in their suitability for a developing endoparasitoid; in particular, the host immune response, which can suppress egg hatching and larval development, has been hypothesized to be one of the most important determinants of parasitoid host range. In this study, we investigated whether three bumblebee host species (Bombus bimaculatus, Bombus griseocollis, and Bombus impatiens) varied in their suitability for the development of a shared parasitoid, the conopid fly (Conopidae, Diptera) and whether the intensity of host encapsulation response, an insect immune defense against invaders, could predict parasitoid success. When surgically implanted with a nylon filament, B. griseocollis exhibited a stronger immune response than both B. impatiens and B. bimaculatus. Similarly, B. griseocollis was more likely to melanize conopid larvae from natural infections and more likely to kill conopids prior to its own death. Our results indicate that variation in the strength of the general immune response of insects may have ecological implications for sympatric species that share parasites. We suggest that, in this system, selection for a stronger immune response may be heightened by the pattern of phenological overlap between local host species and the population peak of their most prominent parasitoid. PMID:25795253

  15. Paroxysmal nocturnal hemoglobinuria and telomere length predicts response to immunosuppressive therapy in pediatric aplastic anemia.

    Science.gov (United States)

    Narita, Atsushi; Muramatsu, Hideki; Sekiya, Yuko; Okuno, Yusuke; Sakaguchi, Hirotoshi; Nishio, Nobuhiro; Yoshida, Nao; Wang, Xinan; Xu, Yinyan; Kawashima, Nozomu; Doisaki, Sayoko; Hama, Asahito; Takahashi, Yoshiyuki; Kudo, Kazuko; Moritake, Hiroshi; Kobayashi, Masao; Kobayashi, Ryoji; Ito, Etsuro; Yabe, Hiromasa; Ohga, Shouichi; Ohara, Akira; Kojima, Seiji

    2015-12-01

    Acquired aplastic anemia is an immune-mediated disease characterized by severe defects in stem cell number resulting in hypocellular marrow and peripheral blood cytopenias. Minor paroxysmal nocturnal hemoglobinuria populations and a short telomere length were identified as predictive biomarkers of immunosuppressive therapy responsiveness in aplastic anemia. We enrolled 113 aplastic anemia patients (63 boys and 50 girls) in this study to evaluate their response to immunosuppressive therapy. The paroxysmal nocturnal hemoglobinuria populations and telomere length were detected by flow cytometry. Forty-seven patients (42%) carried a minor paroxysmal nocturnal hemoglobinuria population. The median telomere length of aplastic anemia patients was -0.99 standard deviation (SD) (range -4.01-+3.01 SD). Overall, 60 patients (53%) responded to immunosuppressive therapy after six months. Multivariate logistic regression analysis identified the absence of a paroxysmal nocturnal hemoglobinuria population and a shorter telomere length as independent unfavorable predictors of immunosuppressive therapy response at six months. The cohort was stratified into a group of poor prognosis (paroxysmal nocturnal hemoglobinuria negative and shorter telomere length; 37 patients) and good prognosis (paroxysmal nocturnal hemoglobinuria positive and/or longer telomere length; 76 patients), respectively. The response rates of the poor prognosis and good prognosis groups at six months were 19% and 70%, respectively (Ptelomere length is an efficient predictor of poor immunosuppressive therapy response, which should be considered while deciding treatment options: immunosuppressive therapy or first-line hematopoietic stem cell transplantation. The trial was registered in www.umin.ac.jp with number UMIN000017972.

  16. Predicting spike occurrence and neuronal responsiveness from LFPs in primary somatosensory cortex.

    Science.gov (United States)

    Storchi, Riccardo; Zippo, Antonio G; Caramenti, Gian Carlo; Valente, Maurizio; Biella, Gabriele E M

    2012-01-01

    Local Field Potentials (LFPs) integrate multiple neuronal events like synaptic inputs and intracellular potentials. LFP spatiotemporal features are particularly relevant in view of their applications both in research (e.g. for understanding brain rhythms, inter-areal neural communication and neuronal coding) and in the clinics (e.g. for improving invasive Brain-Machine Interface devices). However the relation between LFPs and spikes is complex and not fully understood. As spikes represent the fundamental currency of neuronal communication this gap in knowledge strongly limits our comprehension of neuronal phenomena underlying LFPs. We investigated the LFP-spike relation during tactile stimulation in primary somatosensory (S-I) cortex in the rat. First we quantified how reliably LFPs and spikes code for a stimulus occurrence. Then we used the information obtained from our analyses to design a predictive model for spike occurrence based on LFP inputs. The model was endowed with a flexible meta-structure whose exact form, both in parameters and structure, was estimated by using a multi-objective optimization strategy. Our method provided a set of nonlinear simple equations that maximized the match between models and true neurons in terms of spike timings and Peri Stimulus Time Histograms. We found that both LFPs and spikes can code for stimulus occurrence with millisecond precision, showing, however, high variability. Spike patterns were predicted significantly above chance for 75% of the neurons analysed. Crucially, the level of prediction accuracy depended on the reliability in coding for the stimulus occurrence. The best predictions were obtained when both spikes and LFPs were highly responsive to the stimuli. Spike reliability is known to depend on neuron intrinsic properties (i.e. on channel noise) and on spontaneous local network fluctuations. Our results suggest that the latter, measured through the LFP response variability, play a dominant role. PMID:22586452

  17. Predicting spike occurrence and neuronal responsiveness from LFPs in primary somatosensory cortex.

    Directory of Open Access Journals (Sweden)

    Riccardo Storchi

    Full Text Available Local Field Potentials (LFPs integrate multiple neuronal events like synaptic inputs and intracellular potentials. LFP spatiotemporal features are particularly relevant in view of their applications both in research (e.g. for understanding brain rhythms, inter-areal neural communication and neuronal coding and in the clinics (e.g. for improving invasive Brain-Machine Interface devices. However the relation between LFPs and spikes is complex and not fully understood. As spikes represent the fundamental currency of neuronal communication this gap in knowledge strongly limits our comprehension of neuronal phenomena underlying LFPs. We investigated the LFP-spike relation during tactile stimulation in primary somatosensory (S-I cortex in the rat. First we quantified how reliably LFPs and spikes code for a stimulus occurrence. Then we used the information obtained from our analyses to design a predictive model for spike occurrence based on LFP inputs. The model was endowed with a flexible meta-structure whose exact form, both in parameters and structure, was estimated by using a multi-objective optimization strategy. Our method provided a set of nonlinear simple equations that maximized the match between models and true neurons in terms of spike timings and Peri Stimulus Time Histograms. We found that both LFPs and spikes can code for stimulus occurrence with millisecond precision, showing, however, high variability. Spike patterns were predicted significantly above chance for 75% of the neurons analysed. Crucially, the level of prediction accuracy depended on the reliability in coding for the stimulus occurrence. The best predictions were obtained when both spikes and LFPs were highly responsive to the stimuli. Spike reliability is known to depend on neuron intrinsic properties (i.e. on channel noise and on spontaneous local network fluctuations. Our results suggest that the latter, measured through the LFP response variability, play a dominant role.

  18. Individual differences in cortisol stress response predict increases in voice pitch during exam stress.

    Science.gov (United States)

    Pisanski, Katarzyna; Nowak, Judyta; Sorokowski, Piotr

    2016-09-01

    Despite a long history of empirical research, the potential vocal markers of stress remain unclear. Previous studies examining speech under stress most consistently report an increase in voice pitch (the acoustic correlate of fundamental frequency, F0), however numerous studies have failed to replicate this finding. In the present study we tested the prediction that these inconsistencies are tied to variation in the severity of the stress response, wherein voice changes may be observed predominantly among individuals who show a cortisol stress response (i.e., an increase in free cortisol levels) above a critical threshold. Voice recordings and saliva samples were collected from university psychology students at baseline and again immediately prior to an oral examination. Voice recordings included both read and spontaneous speech, from which we measured mean, minimum, maximum, and the standard deviation in F0. We observed an increase in mean and minimum F0 under stress in both read and spontaneous speech, whereas maximum F0 and its standard deviation showed no systematic changes under stress. Our results confirmed that free cortisol levels increased by an average of 74% (ranging from 0 to 270%) under stress. Critically, increases in cortisol concentrations significantly predicted increases in mean F0 under stress for both speech types, but did not predict variation in F0 at baseline. On average, stress-induced increases in voice pitch occurred only when free cortisol levels more than doubled their baseline concentrations. Our results suggest that researchers examining speech under stress should control for individual differences in the magnitude of the stress response. PMID:27188981

  19. Quantification in gas chromatography: prediction of flame ionization detector response factors from combustion enthalpies and molecular structures.

    Science.gov (United States)

    de Saint Laumer, Jean-Yves; Cicchetti, Esmeralda; Merle, Philippe; Egger, Jonathan; Chaintreau, Alain

    2010-08-01

    In a previous report, we validated the use of a database that compiled the relative response factors of flavor and fragrance compounds under standard GC conditions for a flame ionization detector. Here we investigate the prediction of unknown response factors from the molecular structure by using combustion enthalpies. In a first step, this enthalpy was well-predicted with either ab initio calculation or multiple linear regression based on the molecular formula. In a second step, good correlation was observed between these combustion enthalpies and experimental relative response factors, and so the response factors were predictable from only the molecular formula. With a database of 351 compounds, about 60% of them exhibited a difference of less than 5% between the predicted and experimental relative response factors and about 80% exhibited a difference of less than 10%. PMID:20700911

  20. Prediction

    CERN Document Server

    Sornette, Didier

    2010-01-01

    This chapter first presents a rather personal view of some different aspects of predictability, going in crescendo from simple linear systems to high-dimensional nonlinear systems with stochastic forcing, which exhibit emergent properties such as phase transitions and regime shifts. Then, a detailed correspondence between the phenomenology of earthquakes, financial crashes and epileptic seizures is offered. The presented statistical evidence provides the substance of a general phase diagram for understanding the many facets of the spatio-temporal organization of these systems. A key insight is to organize the evidence and mechanisms in terms of two summarizing measures: (i) amplitude of disorder or heterogeneity in the system and (ii) level of coupling or interaction strength among the system's components. On the basis of the recently identified remarkable correspondence between earthquakes and seizures, we present detailed information on a class of stochastic point processes that has been found to be particu...

  1. Evaluation of Response Prediction Procedures using Full Scale Measurements for a Container Ship

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher; Nielsen, Ulrik Dam

    2013-01-01

    This paper deals with the analysis of recent full-scale strain measurements in the hull of a large container carrier covering several months of operation. The focus is on the real-time prediction accuracy of responses 5-15 seconds ahead of the measurements. Such results are less applicable...... in the operation of container carriers but are important in e.g. loading/unloading operations at sea or helicopter landings. Three different procedures are discussed: Conditional processes with analytical estimates of the mean values and standard deviations, the autoregressive predictor method and a method based...... Large Container Ships (TULCS) project no. 234146....

  2. Comparison between genomic predictions using daughter yield deviation and conventional estimated breeding value as response variables

    DEFF Research Database (Denmark)

    Guo, Gang; Lund, Mogens Sandø; Zhang, Y;

    2010-01-01

    This study compared genomic predictions using conventional estimated breeding values (EBV) and daughter yield deviations (DYD) as response variables based on simulated data. Eight scenarios were simulated in regard to heritability (0.05 and 0.30), number of daughters per sire (30, 100, and unequal......), the EBV and DYD approaches provided similar genomic estimated breeding value (GEBV) reliabilities, except for scenarios with unequal numbers of daughters and half of sires without genotype, for which the EBV approach was superior to the DYD approach (by 1.2 and 2.4%). Using a Bayesian mixture prior model...

  3. Strategies for numerical prediction of the uncertainty in the material response of solid foams

    Energy Technology Data Exchange (ETDEWEB)

    Hohe, Joerg; Beckmann, Carla [Fraunhofer-Institut fuer Werkstoffmechanik (IWM), Freiburg im Breisgau (Germany); Hardenacke, Volker [Karlsruher Institut fuer Technologie, Karlsruhe (Germany)

    2010-07-01

    The present study is concerned with a numerical prediction of uncertainty effects in the macroscopic material response of solid foams and other cellular solids used as a lightweight material for reduction of the energy consumption in all fields of transport. Two different routes are proposed. In a first approach, a repeated analysis of small scale volume elements for the microstructure is performed. As an alternative, large scale representative volume elements for the microstructure are considered where the stochastic information is generated by applying the homogenization scheme to subsets (''testing volume elements'') defined by the individual cells or cell clusters. (orig.)

  4. Precise prediction model and simplified scoring system for sustained combined response to interferon-α

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To establish a predictive algorithm which may serve for selecting optimal candidates for interferon-α(IFN-α) treatment.METHODS:A total of 474 IFN-α treated hepatitis B virus e antigen(HBeAg)-positive patients were enrolled in the present study.The patients' baseline characteristics,such as age,gender,blood tests,activity grading(G) of intrahepatic inflammation,score(S) of liver fibrosis,hepatitis B virus(HBV) DNA and genotype were evaluated;therapy duration and response of each patient at the 24th wk af...

  5. Predicting the crack response for a pipe with a complex crack

    Science.gov (United States)

    Lukes, Robert G.

    Traditional flaw evaluation in the nuclear field uses conservative methods to predict maximum load carrying capacity for flaws in a given pipe. There is a need in the nuclear industry for more accurate estimates of the load carrying capacity of nuclear piping such that probabilistic tools can be used to predict the time to failure for various types of cracks. These more accurate estimates will allow the nuclear industry to repair flaws at a more appropriate time considering external factors such as costs and man-rem planning along with the flaw repair. Analysis of the maximum load carrying capacity of a pipe with a complex crack (CC) has gained increased importance due to the recent identification of long CC's that have appeared in dissimilar metal (DM) welds thought to be caused by primary water stress corrosion cracking (PWSCC). A coded solution for a single material with a weld was developed that gives an accurate maximum load and crack driving force prediction for a pipe with a through wall crack (TWC), called LBBEng. To support the analysis of a CC, traditionally, an assumption is used that the CC performs similar to that of a TWC of a reduced thickness (TWCr). This modification gives a conservative prediction of the maximum load carrying capacity for a CC in a single material but was never verified for a CC in a DM weld. From the evaluation of the DM weld test data, along with finite element analysis, it can be demonstrated that the crack response of a CC can be predicted by a TWC model when modifications are made to the reduced thickness method.

  6. An Effective Approach Based on Response Surface Methodology for Predicting Friction Welding Parameters

    Science.gov (United States)

    Celik, Sare; Deniz Karaoglan, Aslan; Ersozlu, Ismail

    2016-03-01

    The joining of dissimilar metals is one of the most essential necessities of industries. Manufacturing by the joint of alloy steel and normal carbon steel is used in production, because it decreases raw material cost. The friction welding process parameters such as friction pressure, friction time, upset pressure, upset time and rotating speed play the major roles in determining the strength and microstructure of the joints. In this study, response surface methodology (RSM), which is a well-known design of experiments approach, is used for modeling the mathematical relation between the responses (tensile strength and maximum temperature), and the friction welding parameters with minimum number of experiments. The results show that RSM is an effective method for this type of problems for developing models and prediction.

  7. Prediction of response to chemotherapy by ERCC1 immunohistochemistry and ERCC1 polymorphism in ovarian cancer

    DEFF Research Database (Denmark)

    Dahl Steffensen, Karina; Waldstrøm, M.; Jeppesen, Ulla;

    2007-01-01

    The response of tumor cells to platinum-based chemotherapy involves DNA repair mechanisms. Excision repair cross-complementation group 1 (ercc1) is one of the leading genes involved in DNA repair, and several studies have linked ercc1 to platinum resistance in cell lines and in human cancers....... A common single nucleotide polymorphism (SNP) of ercc1 at codon 118 has been proposed to impair ercc1 translation and reduce ERCC1 protein expression and consequently influence the response to platinum-based chemotherapy. The primary aim of the present study was to evaluate ERCC1 expression and ercc1 codon...... 118 polymorphism in epithelial ovarian cancer (EOC) and their possible predictive value in patients treated with platinum-based chemotherapy. Formalin-fixed, paraffin-embedded tissue sections from 159 patients with advanced EOC were used for immunohistochemistry. Ercc1 codon 118 SNP genotyping...

  8. Earthquake Risk - SEISMIC_SHAKING_PREDICTED_RESPONSE_RP35_IN: Predicted Responses of Geologic Materials to Seismically Induced Ground Shaking (Indiana Geological Survey, 1:500,000, Polygon Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — SEISMIC_SHAKING_PREDICTED_RESPONSE_RP35_IN is a polygon shapefile that shows the distribution and classification of National Earthquake Hazards Reduction Program...

  9. Computer-aided breast MR image feature analysis for prediction of tumor response to chemotherapy

    International Nuclear Information System (INIS)

    Purpose: To identify a new clinical marker based on quantitative kinetic image features analysis and assess its feasibility to predict tumor response to neoadjuvant chemotherapy. Methods: The authors assembled a dataset involving breast MR images acquired from 68 cancer patients before undergoing neoadjuvant chemotherapy. Among them, 25 patients had complete response (CR) and 43 had partial and nonresponse (NR) to chemotherapy based on the response evaluation criteria in solid tumors. The authors developed a computer-aided detection scheme to segment breast areas and tumors depicted on the breast MR images and computed a total of 39 kinetic image features from both tumor and background parenchymal enhancement regions. The authors then applied and tested two approaches to classify between CR and NR cases. The first one analyzed each individual feature and applied a simple feature fusion method that combines classification results from multiple features. The second approach tested an attribute selected classifier that integrates an artificial neural network (ANN) with a wrapper subset evaluator, which was optimized using a leave-one-case-out validation method. Results: In the pool of 39 features, 10 yielded relatively higher classification performance with the areas under receiver operating characteristic curves (AUCs) ranging from 0.61 to 0.78 to classify between CR and NR cases. Using a feature fusion method, the maximum AUC = 0.85 ± 0.05. Using the ANN-based classifier, AUC value significantly increased to 0.96 ± 0.03 (p < 0.01). Conclusions: This study demonstrated that quantitative analysis of kinetic image features computed from breast MR images acquired prechemotherapy has potential to generate a useful clinical marker in predicting tumor response to chemotherapy

  10. Computer-aided breast MR image feature analysis for prediction of tumor response to chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Aghaei, Faranak; Tan, Maxine; Liu, Hong; Zheng, Bin, E-mail: Bin.Zheng-1@ou.edu [School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019 (United States); Hollingsworth, Alan B. [Mercy Women’s Center, Mercy Health Center, Oklahoma City, Oklahoma 73120 (United States); Qian, Wei [Department of Electrical and Computer Engineering, University of Texas, El Paso, Texas 79968 (United States)

    2015-11-15

    Purpose: To identify a new clinical marker based on quantitative kinetic image features analysis and assess its feasibility to predict tumor response to neoadjuvant chemotherapy. Methods: The authors assembled a dataset involving breast MR images acquired from 68 cancer patients before undergoing neoadjuvant chemotherapy. Among them, 25 patients had complete response (CR) and 43 had partial and nonresponse (NR) to chemotherapy based on the response evaluation criteria in solid tumors. The authors developed a computer-aided detection scheme to segment breast areas and tumors depicted on the breast MR images and computed a total of 39 kinetic image features from both tumor and background parenchymal enhancement regions. The authors then applied and tested two approaches to classify between CR and NR cases. The first one analyzed each individual feature and applied a simple feature fusion method that combines classification results from multiple features. The second approach tested an attribute selected classifier that integrates an artificial neural network (ANN) with a wrapper subset evaluator, which was optimized using a leave-one-case-out validation method. Results: In the pool of 39 features, 10 yielded relatively higher classification performance with the areas under receiver operating characteristic curves (AUCs) ranging from 0.61 to 0.78 to classify between CR and NR cases. Using a feature fusion method, the maximum AUC = 0.85 ± 0.05. Using the ANN-based classifier, AUC value significantly increased to 0.96 ± 0.03 (p < 0.01). Conclusions: This study demonstrated that quantitative analysis of kinetic image features computed from breast MR images acquired prechemotherapy has potential to generate a useful clinical marker in predicting tumor response to chemotherapy.

  11. The effect of cell size distribution on predicted osmotic responses of cells.

    Science.gov (United States)

    Elmoazzen, H Y; Chan, C C V; Acker, J P; Elliott, J A W; McGann, L E

    2005-01-01

    An understanding of the kinetics of the osmotic response of cells is important in understanding permeability properties of cell membranes and predicting cell responses during exposure to anisotonic conditions. Traditionally, a mathematical model of cell osmotic response is obtained by applying mass transport and Boyle-vant Hoff equations using numerical methods. In the usual application of these equations, it is assumed that all cells are the same size equal to the mean or mode of the population. However, biological cells (even if they had identical membranes and hence identical permeability characteristics--which they do not) have a distribution in cell size and will therefore shrink or swell at different rates when exposed to anisotonic conditions. A population of cells may therefore exhibit a different average osmotic response than that of a single cell. In this study, a mathematical model using mass transport and Boyle-van't Hoff equations was applied to measured size distributions of cells. Chinese hamster fibroblast cells (V-79W) and Madin-Darby canine kidney cells (MDCK), were placed in hypertonic solutions and the kinetics of cell shrinkage were monitored. Consistent with the theoretical predictions, the size distributions of these cells were found to change over time, therefore the selection of the measure of central tendency for the population may affect the calculated osmotic parameters. After examining three different average volumes (mean, median, and mode) using four different theoretical cell size distributions, it was determined that, for the assumptions used in this study, the mean or median were the best measures of central tendency to describe osmotic volume changes in cell suspensions. PMID:16082441

  12. TNF-α Promoter Polymorphisms Predict the Response to Etanercept More Powerfully than that to Infliximab/Adalimumab in Spondyloarthritis.

    Science.gov (United States)

    Liu, Jing; Dong, Zheng; Zhu, Qi; He, Dongyi; Ma, Yanyun; Du, Aiping; He, Fan; Zhao, Dongbao; Xu, Xia; Zhang, Hui; Jin, Li; Wang, Jiucun

    2016-08-31

    While previous studies have researched in association analyses between TNFα promoter polymorphisms and responses to TNF blockers in spondyloarthritis patients, their results were conflicting. Therefore, we aimed to determine whether TNFα promoter polymorphisms could predict response to TNF blockers and find the source of heterogeneity. Data were extracted and analyzed from published articles and combined with our unpublished data. We found that the greatest potential sources of heterogeneity in the results were gender ratio, disease type, continents, and TNF blockers. Then Stratification analysis showed that the TNFα -308 G allele and the -238 G allele predicted a good response to TNF blockers (OR = 2.64 [1.48-4.73]; 2.52 [1.46-4.37]). However, G alleles of TNFα -308 and -238 could predict the response to etanercept (OR = 4.02 [2.24-7.23]; 5.17 [2.29-11.67]) much more powerfully than the response to infiliximab/adalimumab (OR = 1.68 [1.02-2.78]; 1.28 [0.57-2.86]). TNFα -857 could not predict the response in either subgroup. Cumulative meta-analysis performed in ankylosing spondylitis patients presented the odds ratio decreased with stricter response criteria. In conclusion, TNFα -308 A/G and -238 A/G are more powerful to predict the response to Etanercept and it is dependent on the criteria of response.

  13. Predicting the responsiveness of soil biodiversity to deforestation: a cross-biome study.

    Science.gov (United States)

    Crowther, Thomas W; Maynard, Daniel S; Leff, Jonathan W; Oldfield, Emily E; McCulley, Rebecca L; Fierer, Noah; Bradford, Mark A

    2014-09-01

    The consequences of deforestation for aboveground biodiversity have been a scientific and political concern for decades. In contrast, despite being a dominant component of biodiversity that is essential to the functioning of ecosystems, the responses of belowground biodiversity to forest removal have received less attention. Single-site studies suggest that soil microbes can be highly responsive to forest removal, but responses are highly variable, with negligible effects in some regions. Using high throughput sequencing, we characterize the effects of deforestation on microbial communities across multiple biomes and explore what determines the vulnerability of microbial communities to this vegetative change. We reveal consistent directional trends in the microbial community response, yet the magnitude of this vegetation effect varied between sites, and was explained strongly by soil texture. In sandy sites, the difference in vegetation type caused shifts in a suite of edaphic characteristics, driving substantial differences in microbial community composition. In contrast, fine-textured soil buffered microbes against these effects and there were minimal differences between communities in forest and grassland soil. These microbial community changes were associated with distinct changes in the microbial catabolic profile, placing community changes in an ecosystem functioning context. The universal nature of these patterns allows us to predict where deforestation will have the strongest effects on soil biodiversity, and how these effects could be mitigated.

  14. Predicting the responsiveness of soil biodiversity to deforestation: a cross-biome study.

    Science.gov (United States)

    Crowther, Thomas W; Maynard, Daniel S; Leff, Jonathan W; Oldfield, Emily E; McCulley, Rebecca L; Fierer, Noah; Bradford, Mark A

    2014-09-01

    The consequences of deforestation for aboveground biodiversity have been a scientific and political concern for decades. In contrast, despite being a dominant component of biodiversity that is essential to the functioning of ecosystems, the responses of belowground biodiversity to forest removal have received less attention. Single-site studies suggest that soil microbes can be highly responsive to forest removal, but responses are highly variable, with negligible effects in some regions. Using high throughput sequencing, we characterize the effects of deforestation on microbial communities across multiple biomes and explore what determines the vulnerability of microbial communities to this vegetative change. We reveal consistent directional trends in the microbial community response, yet the magnitude of this vegetation effect varied between sites, and was explained strongly by soil texture. In sandy sites, the difference in vegetation type caused shifts in a suite of edaphic characteristics, driving substantial differences in microbial community composition. In contrast, fine-textured soil buffered microbes against these effects and there were minimal differences between communities in forest and grassland soil. These microbial community changes were associated with distinct changes in the microbial catabolic profile, placing community changes in an ecosystem functioning context. The universal nature of these patterns allows us to predict where deforestation will have the strongest effects on soil biodiversity, and how these effects could be mitigated. PMID:24692253

  15. Rituximab-induced depletion of anti-PLA2R autoantibodies predicts response in membranous nephropathy.

    Science.gov (United States)

    Beck, Laurence H; Fervenza, Fernando C; Beck, David M; Bonegio, Ramon G B; Malik, Fahim A; Erickson, Stephen B; Cosio, Fernando G; Cattran, Daniel C; Salant, David J

    2011-08-01

    Autoantibodies to the M-type phospholipase A(2) receptor (PLA(2)R) are sensitive and specific for idiopathic membranous nephropathy. The anti-B cell agent rituximab is a promising therapy for this disease, but biomarkers of early response to treatment currently do not exist. Here, we investigated whether levels of anti-PLA(2)R correlate with the immunological activity of membranous nephropathy, potentially exhibiting a more rapid response to treatment than clinical parameters such as proteinuria. We measured the amount of anti-PLA(2)R using Western blot immunoassay in serial serum samples from a total of 35 patients treated with rituximab for membranous nephropathy in two distinct cohorts. Pretreatment samples from 25 of 35 (71%) patients contained anti-PLA(2)R, and these autoantibodies declined or disappeared in 17 (68%) of these patients within 12 months after rituximab. Those who demonstrated this immunologic response fared better clinically: 59% and 88% attained complete or partial remission by 12 and 24 months, respectively, compared with 0% and 33% among those with persistent anti-PLA(2)R levels. Changes in antibody levels preceded changes in proteinuria. One subject who relapsed during follow-up had a concomitant return of anti-PLA(2)R. In summary, measuring anti-PLA(2)R levels by immunoassay may be a method to follow and predict response to treatment with rituximab in membranous nephropathy.

  16. CT contrast predicts pancreatic cancer treatment response to verteporfin-based photodynamic therapy

    Science.gov (United States)

    Jermyn, Michael; Davis, Scott C.; Dehghani, Hamid; Huggett, Matthew T.; Hasan, Tayyaba; Pereira, Stephen P.; Bown, Stephen G.; Pogue, Brian W.

    2014-04-01

    The goal of this study was to determine dominant factors affecting treatment response in pancreatic cancer photodynamic therapy (PDT), based on clinically available information in the VERTPAC-01 trial. This trial investigated the safety and efficacy of verteporfin PDT in 15 patients with locally advanced pancreatic adenocarcinoma. CT scans before and after contrast enhancement from the 15 patients in the VERTPAC-01 trial were used to determine venous-phase blood contrast enhancement and this was correlated with necrotic volume determined from post-treatment CT scans, along with estimation of optical absorption in the pancreas for use in light modeling of the PDT treatment. Energy threshold contours yielded estimates for necrotic volume based on this light modeling. Both contrast-derived venous blood content and necrotic volume from light modeling yielded strong correlations with observed necrotic volume (R2 = 0.85 and 0.91, respectively). These correlations were much stronger than those obtained by correlating energy delivered versus necrotic volume in the VERTPAC-01 study and in retrospective analysis from a prior clinical study. This demonstrates that contrast CT can provide key surrogate dosimetry information to assess treatment response. It also implies that light attenuation is likely the dominant factor in the VERTPAC treatment response, as opposed to other factors such as drug distribution. This study is the first to show that contrast CT provides needed surrogate dosimetry information to predict treatment response in a manner which uses standard-of-care clinical images, rather than invasive dosimetry methods.

  17. When power shapes interpersonal behavior: Low relationship power predicts men's aggressive responses to low situational power.

    Science.gov (United States)

    Overall, Nickola C; Hammond, Matthew D; McNulty, James K; Finkel, Eli J

    2016-08-01

    When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (a) only within power-relevant relationship interactions when situational power was low, and (b) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples' observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples' support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men's aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive behavior toward their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. (PsycINFO Database Record PMID:27442766

  18. CT contrast predicts pancreatic cancer treatment response to verteporfin-based photodynamic therapy

    International Nuclear Information System (INIS)

    The goal of this study was to determine dominant factors affecting treatment response in pancreatic cancer photodynamic therapy (PDT), based on clinically available information in the VERTPAC-01 trial. This trial investigated the safety and efficacy of verteporfin PDT in 15 patients with locally advanced pancreatic adenocarcinoma. CT scans before and after contrast enhancement from the 15 patients in the VERTPAC-01 trial were used to determine venous-phase blood contrast enhancement and this was correlated with necrotic volume determined from post-treatment CT scans, along with estimation of optical absorption in the pancreas for use in light modeling of the PDT treatment. Energy threshold contours yielded estimates for necrotic volume based on this light modeling. Both contrast-derived venous blood content and necrotic volume from light modeling yielded strong correlations with observed necrotic volume (R2 = 0.85 and 0.91, respectively). These correlations were much stronger than those obtained by correlating energy delivered versus necrotic volume in the VERTPAC-01 study and in retrospective analysis from a prior clinical study. This demonstrates that contrast CT can provide key surrogate dosimetry information to assess treatment response. It also implies that light attenuation is likely the dominant factor in the VERTPAC treatment response, as opposed to other factors such as drug distribution. This study is the first to show that contrast CT provides needed surrogate dosimetry information to predict treatment response in a manner which uses standard-of-care clinical images, rather than invasive dosimetry methods. (paper)

  19. Trisomy 3 may predict a poor response of gastric MALT lymphoma to Helicobacter pylori eradication therapy

    Institute of Scientific and Technical Information of China (English)

    Sawako Taji; Masuji Morita; Masafumi Taniwaki; Kenichi Nomura; Yosuke Matsumoto; Hideaki Sakabe; Naohisa Yoshida; Shoji Mitsufuji; Kazuhiro Nishida; Shigeo Horiike; Shigeo Nakamura

    2005-01-01

    AIM: To investigate the relation of the response to Helicobacter pylori eradication therapy to the depth of tumor invasion and chromosome abnormalities in patients with mucosaassociated lymphoid tissue (MALT) lymphoma and to determine the clinical value of aneuploidy.METHODS: We studied 13 patients with localized gastric MALT lymphoma of stage E1. Before eradication therapy,the depth of tumor invasion was assessed by endoscopic ultrasonography in 8 patients and by endoscopic examination and gastrointestinal series in the remaining patients. To detect chromosomal abnormalities, paraffin-embedded tissue sections of diagnostic biopsy specimens underwent tissuefluorescence in situ hybridization (FISH), using chromosomespecific α-satellite DNA probes for chromosomes 3,7,12,and 18 and YAC clones for t(11;18)(q21;q21).RESULTS: Seven of the 13 patients had complete regression(CR) in response to H pylori eradication therapy. No patient with CR had submucosal tumor invasion. Trisomy 18 was seen in 1 patient with CR, and both trisomies 12 and 18 were present in another patient with CR. All patients with no response or progressive disease had deep submucosal tumor invasion and showed t(11;18)(q21;q21) or trisomy 3. Trisomy 7 was not detected in this series of patients.CONCLUSION: The depth of tumor invasion is an accurate predictor of the response of stage E1 MALT lymphoma to H pylori eradication therapy and is closely associated with the presence of chromosomal abnormalities. Trisomy 3 may predict the aggressive development of MALT lymphoma.

  20. When power shapes interpersonal behavior: Low relationship power predicts men's aggressive responses to low situational power.

    Science.gov (United States)

    Overall, Nickola C; Hammond, Matthew D; McNulty, James K; Finkel, Eli J

    2016-08-01

    When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (a) only within power-relevant relationship interactions when situational power was low, and (b) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples' observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples' support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men's aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive behavior toward their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. (PsycINFO Database Record

  1. Gene expression signature of fibroblast serum response predicts human cancer progression: similarities between tumors and wounds.

    Directory of Open Access Journals (Sweden)

    Howard Y Chang

    2004-02-01

    Full Text Available Cancer invasion and metastasis have been likened to wound healing gone awry. Despite parallels in cellular behavior between cancer progression and wound healing, the molecular relationships between these two processes and their prognostic implications are unclear. In this study, based on gene expression profiles of fibroblasts from ten anatomic sites, we identify a stereotyped gene expression program in response to serum exposure that appears to reflect the multifaceted role of fibroblasts in wound healing. The genes comprising this fibroblast common serum response are coordinately regulated in many human tumors, allowing us to identify tumors with gene expression signatures suggestive of active wounds. Genes induced in the fibroblast serum-response program are expressed in tumors by the tumor cells themselves, by tumor-associated fibroblasts, or both. The molecular features that define this wound-like phenotype are evident at an early clinical stage, persist during treatment, and predict increased risk of metastasis and death in breast, lung, and gastric carcinomas. Thus, the transcriptional signature of the response of fibroblasts to serum provides a possible link between cancer progression and wound healing, as well as a powerful predictor of the clinical course in several common carcinomas.

  2. A Framework for Prediction of Response to HCV Therapy Using Different Data Mining Techniques

    Directory of Open Access Journals (Sweden)

    Enas M. F. El Houby

    2014-01-01

    Full Text Available Hepatitis C which is a widely spread disease all over the world is a fatal liver disease caused by Hepatitis C Virus (HCV. The only approved therapy is interferon plus ribavirin. The number of responders to this treatment is low, while its cost is high and side effects are undesirable. Treatment response prediction will help in reducing the patients who suffer from the side effects and high costs without achieving recovery. The aim of this research is to develop a framework which can select the best model to predict HCV patients’ response to the treatment of HCV from clinical information. The framework contains three phases which are preprocessing phase to prepare the data for applying Data Mining (DM techniques, DM phase to apply different DM techniques, and evaluation phase to evaluate and compare the performance of the built models and select the best model as the recommended one. Different DM techniques had been applied which are associative classification, artificial neural network, and decision tree to evaluate the framework. The experimental results showed the effectiveness of the framework in selecting the best model which is the model built by associative classification using histology activity index, fibrosis stage, and alanine amino transferase.

  3. Predictive Factors of the Response of Rectal Cancer to Neoadjuvant Radiochemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Spolverato, Gaya; Pucciarelli, Salvatore [Department of Oncology and Surgical Sciences, Section of Surgery, University of Padova, Padova 35128 (Italy); Bertorelle, Roberta [Istituto Oncologico Veneto-IRCCS, Padova 35128 (Italy); De Rossi, Anita, E-mail: anita.derossi@unipd.it [Istituto Oncologico Veneto-IRCCS, Padova 35128 (Italy); Department of Oncology and Surgical Sciences, Section of Oncology, University of Padova, Padova 35128 (Italy); Nitti, Donato [Department of Oncology and Surgical Sciences, Section of Surgery, University of Padova, Padova 35128 (Italy)

    2011-04-26

    Locally advanced rectal cancer is currently treated with pre-operative radiochemotherapy (pRCT), but the response is not uniform. Identification of patients with higher likelihood of responding to pRCT is clinically relevant, as patients with resistant tumors could be spared exposure to radiation or DNA-damaging drugs that are associated with adverse side effects. To highlight predictive biomarkers of response to pRCT, a systematic search of PubMed was conducted with a combination of the following terms: “rectal”, “predictive”, “radiochemotherapy”, “neoadjuvant”, “response” and “biomarkers”. Genetic polymorphisms in epithelial growth factor receptor (EGFR) and thymidylate synthase (TS) genes, the expression of several markers, such as EGFR, bcl-2/bax and cyclooxygenase (COX)-2, and circulating biomarkers, such as serum carcinoembryonic antigen (CEA) level, are promising as predictor markers, but need to be further evaluated. The majority of the studies did not support the predictive value of p53, while the values of Ki-67, TS and p21 is still controversial. Gene expression profiles of thousands of genes using microarrays, microRNA studies and the search for new circulating molecules, such as human telomerase reverse transcriptase mRNA and cell-free DNA, are providing interesting results that might lead to the identification of new useful biomarkers. Evaluation of biomarkers in larger, prospective trials are required to guide therapeutic strategies.

  4. EGFR expression level predicts response and overall survival in gastric cancer PDTX model treated with cetuximab

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Objective:hTe aim of this study was to determine whether the EGFR statuscould significantly predict some benefit in overall survival and response to cetuximab in advanced GC xenografts.Methods: Two hundred xenografts derived from 20 GC patients were established. Then they were divided into cetuximab treated group and control group randomly.Results:Among the cetuximab treated group, 4 GC cases were identified responded to cetuximab.hTose cetuximab treated PDX models had longer OS than non-treated. High EGFR mRNA expression and immunohistochemistry score are more prone to response to cetuximab. EGFR amplification, mRNA and protein overexpression were associated with the OS in cetuximab treated PDX models. Moreover, in the PDX models derived from EGFR ampliifcation, mRNA or protein overexpression cases, the OS is signiifcantly different between the cetuximab treated and control group, while the OS in not statistically different in other cases.Conclusion:EGFR status predicts sensitivity to therapy and survival in GC treated with cetuximab, especially the mRNA and protein expression level.

  5. ULK1: a promising biomarker in predicting poor prognosis and therapeutic response in human nasopharygeal carcinoma.

    Directory of Open Access Journals (Sweden)

    Miao Yun

    Full Text Available Plenty of studies have established that dysregulation of autophagy plays an essential role in cancer progression. The autophagy-related proteins have been reported to be closely associated with human cancer patients' prognosis. We explored the expression dynamics and prognostic value of autophagy-related protein ULK1 by immunochemistry (IHC method in two independent cohorts of nasopharygeal carcinoma (NPC cases. The X-tile program was applied to determine the optimal cut-off value in the training cohort. This derived cutoff value was then subjected to analysis the association of ULK1 expression with patients' clinical characteristics and survival outcome in the validation cohort and overall cases. High ULK1 expression was closely associated with aggressive clinical feature of NPC patients. Furthermore, high expression of ULK1 was observed more frequently in therapeutic resistant group than that in therapeutic effective group. Our univariate and multivariate analysis also showed that higher ULK1 expression predicted inferior disease-specific survival (DSS (P<0.05. Consequently, a new clinicopathologic prognostic model with 3 poor prognostic factors (ie, ULK1 expression, overall clinical stage and therapeutic response could significantly stratify risk (low, intermediate and high for DSS in NPC patients (P<0.001. These findings provide evidence that, the examination of ULK1 expression by IHC method, could serve as an effective additional tool for predicting therapeutic response and patients' survival outcome in NPC patients.

  6. Elevation in inflammatory serum biomarkers predicts response to trastuzumab-containing therapy.

    Directory of Open Access Journals (Sweden)

    Ahmed A Alkhateeb

    Full Text Available Approximately half of all HER2/neu-overexpressing breast cancer patients do not respond to trastuzumab-containing therapy. Therefore, there remains an urgent and unmet clinical need for the development of predictive biomarkers for trastuzumab response. Recently, several lines of evidence have demonstrated that the inflammatory tumor microenvironment is a major contributor to therapy resistance in breast cancer. In order to explore the predictive value of inflammation in breast cancer patients, we measured the inflammatory biomarkers serum ferritin and C-reactive protein (CRP in 66 patients immediately before undergoing trastuzumab-containing therapy and evaluated their progression-free and overall survival. The elevation in pre-treatment serum ferritin (>250 ng/ml or CRP (>7.25 mg/l was a significant predictor of reduced progression-free survival and shorter overall survival. When patients were stratified based on their serum ferritin and CRP levels, patients with elevation in both inflammatory biomarkers had a markedly poorer response to trastuzumab-containing therapy. Therefore, the elevation in inflammatory serum biomarkers may reflect a pathological state that decreases the clinical efficacy of this therapy. Anti-inflammatory drugs and life-style changes to decrease inflammation in cancer patients should be explored as possible strategies to sensitize patients to anti-cancer therapeutics.

  7. A Simple and Accurate Model to Predict Responses to Multi-electrode Stimulation in the Retina.

    Directory of Open Access Journals (Sweden)

    Matias I Maturana

    2016-04-01

    Full Text Available Implantable electrode arrays are widely used in therapeutic stimulation of the nervous system (e.g. cochlear, retinal, and cortical implants. Currently, most neural prostheses use serial stimulation (i.e. one electrode at a time despite this severely limiting the repertoire of stimuli that can be applied. Methods to reliably predict the outcome of multi-electrode stimulation have not been available. Here, we demonstrate that a linear-nonlinear model accurately predicts neural responses to arbitrary patterns of stimulation using in vitro recordings from single retinal ganglion cells (RGCs stimulated with a subretinal multi-electrode array. In the model, the stimulus is projected onto a low-dimensional subspace and then undergoes a nonlinear transformation to produce an estimate of spiking probability. The low-dimensional subspace is estimated using principal components analysis, which gives the neuron's electrical receptive field (ERF, i.e. the electrodes to which the neuron is most sensitive. Our model suggests that stimulation proportional to the ERF yields a higher efficacy given a fixed amount of power when compared to equal amplitude stimulation on up to three electrodes. We find that the model captures the responses of all the cells recorded in the study, suggesting that it will generalize to most cell types in the retina. The model is computationally efficient to evaluate and, therefore, appropriate for future real-time applications including stimulation strategies that make use of recorded neural activity to improve the stimulation strategy.

  8. A Simple and Accurate Model to Predict Responses to Multi-electrode Stimulation in the Retina.

    Science.gov (United States)

    Maturana, Matias I; Apollo, Nicholas V; Hadjinicolaou, Alex E; Garrett, David J; Cloherty, Shaun L; Kameneva, Tatiana; Grayden, David B; Ibbotson, Michael R; Meffin, Hamish

    2016-04-01

    Implantable electrode arrays are widely used in therapeutic stimulation of the nervous system (e.g. cochlear, retinal, and cortical implants). Currently, most neural prostheses use serial stimulation (i.e. one electrode at a time) despite this severely limiting the repertoire of stimuli that can be applied. Methods to reliably predict the outcome of multi-electrode stimulation have not been available. Here, we demonstrate that a linear-nonlinear model accurately predicts neural responses to arbitrary patterns of stimulation using in vitro recordings from single retinal ganglion cells (RGCs) stimulated with a subretinal multi-electrode array. In the model, the stimulus is projected onto a low-dimensional subspace and then undergoes a nonlinear transformation to produce an estimate of spiking probability. The low-dimensional subspace is estimated using principal components analysis, which gives the neuron's electrical receptive field (ERF), i.e. the electrodes to which the neuron is most sensitive. Our model suggests that stimulation proportional to the ERF yields a higher efficacy given a fixed amount of power when compared to equal amplitude stimulation on up to three electrodes. We find that the model captures the responses of all the cells recorded in the study, suggesting that it will generalize to most cell types in the retina. The model is computationally efficient to evaluate and, therefore, appropriate for future real-time applications including stimulation strategies that make use of recorded neural activity to improve the stimulation strategy. PMID:27035143

  9. Final Scientific Technical Report: INTEGRATED PREDICTIVE DEMAND RESPONSE CONTROLLER FOR COMMERCIAL BUILDINGS

    Energy Technology Data Exchange (ETDEWEB)

    Wenzel, Mike

    2013-10-14

    This project provides algorithms to perform demand response using the thermal mass of a building. Using the thermal mass of the building is an attractive method for performing demand response because there is no need for capital expenditure. The algorithms rely on the thermal capacitance inherent in the building?s construction materials. A near-optimal ?day ahead? predictive approach is developed that is meant to keep the building?s electrical demand constant during the high cost periods. This type of approach is appropriate for both time-of-use and critical peak pricing utility rate structures. The approach uses the past days data in order to determine the best temperature setpoints for the building during the high price periods on the next day. A second ?model predictive approach? (MPC) uses a thermal model of the building to determine the best temperature for the next sample period. The approach uses constant feedback from the building and is capable of appropriately handling real time pricing. Both approaches are capable of using weather forecasts to improve performance.

  10. Blinded prospective evaluation of computer-based mechanistic schizophrenia disease model for predicting drug response.

    Science.gov (United States)

    Geerts, Hugo; Spiros, Athan; Roberts, Patrick; Twyman, Roy; Alphs, Larry; Grace, Anthony A

    2012-01-01

    The tremendous advances in understanding the neurobiological circuits involved in schizophrenia have not translated into more effective treatments. An alternative strategy is to use a recently published 'Quantitative Systems Pharmacology' computer-based mechanistic disease model of cortical/subcortical and striatal circuits based upon preclinical physiology, human pathology and pharmacology. The physiology of 27 relevant dopamine, serotonin, acetylcholine, norepinephrine, gamma-aminobutyric acid (GABA) and glutamate-mediated targets is calibrated using retrospective clinical data on 24 different antipsychotics. The model was challenged to predict quantitatively the clinical outcome in a blinded fashion of two experimental antipsychotic drugs; JNJ37822681, a highly selective low-affinity dopamine D(2) antagonist and ocaperidone, a very high affinity dopamine D(2) antagonist, using only pharmacology and human positron emission tomography (PET) imaging data. The model correctly predicted the lower performance of JNJ37822681 on the positive and negative syndrome scale (PANSS) total score and the higher extra-pyramidal symptom (EPS) liability compared to olanzapine and the relative performance of ocaperidone against olanzapine, but did not predict the absolute PANSS total score outcome and EPS liability for ocaperidone, possibly due to placebo responses and EPS assessment methods. Because of its virtual nature, this modeling approach can support central nervous system research and development by accounting for unique human drug properties, such as human metabolites, exposure, genotypes and off-target effects and can be a helpful tool for drug discovery and development. PMID:23251349

  11. Blinded prospective evaluation of computer-based mechanistic schizophrenia disease model for predicting drug response.

    Directory of Open Access Journals (Sweden)

    Hugo Geerts

    Full Text Available The tremendous advances in understanding the neurobiological circuits involved in schizophrenia have not translated into more effective treatments. An alternative strategy is to use a recently published 'Quantitative Systems Pharmacology' computer-based mechanistic disease model of cortical/subcortical and striatal circuits based upon preclinical physiology, human pathology and pharmacology. The physiology of 27 relevant dopamine, serotonin, acetylcholine, norepinephrine, gamma-aminobutyric acid (GABA and glutamate-mediated targets is calibrated using retrospective clinical data on 24 different antipsychotics. The model was challenged to predict quantitatively the clinical outcome in a blinded fashion of two experimental antipsychotic drugs; JNJ37822681, a highly selective low-affinity dopamine D(2 antagonist and ocaperidone, a very high affinity dopamine D(2 antagonist, using only pharmacology and human positron emission tomography (PET imaging data. The model correctly predicted the lower performance of JNJ37822681 on the positive and negative syndrome scale (PANSS total score and the higher extra-pyramidal symptom (EPS liability compared to olanzapine and the relative performance of ocaperidone against olanzapine, but did not predict the absolute PANSS total score outcome and EPS liability for ocaperidone, possibly due to placebo responses and EPS assessment methods. Because of its virtual nature, this modeling approach can support central nervous system research and development by accounting for unique human drug properties, such as human metabolites, exposure, genotypes and off-target effects and can be a helpful tool for drug discovery and development.

  12. A Nomogram for Predicting the Pathological Response of Axillary Lymph Node Metastasis in Breast Cancer Patients.

    Science.gov (United States)

    Jin, Xi; Jiang, Yi-Zhou; Chen, Sheng; Shao, Zhi-Ming; Di, Gen-Hong

    2016-01-01

    The value of sentinel lymph node biopsy (SLNB) in post-neoadjuvant chemotherapy (NCT) patients is still controversial. We aimed to identify predictors and construct a nomogram for predicting the pathologically complete response (pCR) of axillary lymph nodes (ALNs) after NCT in node positive breast cancer patients. In total, 426 patients with pathologically proven ALN metastasis before NCT were enrolled, randomized 1:1 and divided into a training set and a validation set. We developed a nomogram based on independent predictors for ALN pCR identified by multivariate logistic regression as well as clinical significant predictors. The multivariate logistic regression analysis showed that hormone receptor (HR) status, human epidermal growth factor 2 (HER2) status and Ki67 index were independent predictors. The nomogram was thereby constructed by those independent predictors as well as tumor size and NCT regimens. The areas under the receiver operating characteristic curve of the training set and the validation set were 0.804 and 0.749, respectively. We constructed a nomogram for predicting ALN pCR in patients who received NCT. Our nomogram can improve risk stratification, accurately predict post-NCT ALN status and avoid unnecessary ALN dissection. PMID:27576704

  13. Prediction of the mechanical response of the femur with uncertain elastic properties.

    Science.gov (United States)

    Wille, Hagen; Rank, Ernst; Yosibash, Zohar

    2012-04-30

    A mandatory requirement for any reliable prediction of the mechanical response of bones, based on quantitative computer tomography, is an accurate relationship between material properties (usually Young's modulus E) and bone density ρ. Many such E-ρ relationships are available based on different experiments on femur specimens with a large spread due to uncertainties. The first goal of this study is to pool and analyze the relevant available experimental data and develop a stochasticE-ρ relationship. This analysis highlights that there is no experimental data available to cover the entire density range of the human femur and that some "popular" E-ρ relationships are based on data that contains extreme scatter, while others are based on a very limited amount of information. The second goal is to use the newly developed stochastic E-ρ relationship in high-order finite element analyses (FEAs) for the computation of strains and displacements in two human proximal femurs, mimicking in vitro experiments. When compared with the experimental observations, the FEA predictions using the median of the stochastic E-ρ relationship follow the underlying distribution of the stochastic E-ρ relationship. Thus, most deviations of the FEA predictions from experimental observations can possibly be explained by uncertain elastic properties of the femur.

  14. Response-predictive gene expression profiling of glioma progenitor cells in vitro.

    Directory of Open Access Journals (Sweden)

    Sylvia Moeckel

    Full Text Available BACKGROUND: High-grade gliomas are amongst the most deadly human tumors. Treatment results are disappointing. Still, in several trials around 20% of patients respond to therapy. To date, diagnostic strategies to identify patients that will profit from a specific therapy do not exist. METHODS: In this study, we used serum-free short-term treated in vitro cell cultures to predict treatment response in vitro. This approach allowed us (a to enrich specimens for brain tumor initiating cells and (b to confront cells with a therapeutic agent before expression profiling. RESULTS: As a proof of principle we analyzed gene expression in 18 short-term serum-free cultures of high-grade gliomas enhanced for brain tumor initiating cells (BTIC before and after in vitro treatment with the tyrosine kinase inhibitor Sunitinib. Profiles from treated progenitor cells allowed to predict therapy-induced impairment of proliferation in vitro. CONCLUSION: For the tyrosine kinase inhibitor Sunitinib used in this dataset, the approach revealed additional predictive information in comparison to the evaluation of classical signaling analysis.

  15. Exploring the Inflammatory Metabolomic Profile to Predict Response to TNF-α Inhibitors in Rheumatoid Arthritis.

    Science.gov (United States)

    Cuppen, Bart V J; Fu, Junzeng; van Wietmarschen, Herman A; Harms, Amy C; Koval, Slavik; Marijnissen, Anne C A; Peeters, Judith J W; Bijlsma, Johannes W J; Tekstra, Janneke; van Laar, Jacob M; Hankemeier, Thomas; Lafeber, Floris P J G; van der Greef, Jan

    2016-01-01

    In clinical practice, approximately one-third of patients with rheumatoid arthritis (RA) respond insufficiently to TNF-α inhibitors (TNFis). The aim of the study was to explore the use of a metabolomics to identify predictors for the outcome of TNFi therapy, and study the metabolomic fingerprint in active RA irrespective of patients' response. In the metabolomic profiling, lipids, oxylipins, and amines were measured in serum samples of RA patients from the observational BiOCURA cohort, before start of biological treatment. Multivariable logistic regression models were established to identify predictors for good- and non-response in patients receiving TNFi (n = 124). The added value of metabolites over prediction using clinical parameters only was determined by comparing the area under receiver operating characteristic curve (AUC-ROC), sensitivity, specificity, positive- and negative predictive value and by the net reclassification index (NRI). The models were further validated by 10-fold cross validation and tested on the complete TNFi treatment cohort including moderate responders. Additionally, metabolites were identified that cross-sectionally associated with the RA disease activity score based on a 28-joint count (DAS28), erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP). Out of 139 metabolites, the best-performing predictors were sn1-LPC(18:3-ω3/ω6), sn1-LPC(15:0), ethanolamine, and lysine. The model that combined the selected metabolites with clinical parameters showed a significant larger AUC-ROC than that of the model containing only clinical parameters (p = 0.01). The combined model was able to discriminate good- and non-responders with good accuracy and to reclassify non-responders with an improvement of 30% (total NRI = 0.23) and showed a prediction error of 0.27. For the complete TNFi cohort, the NRI was 0.22. In addition, 88 metabolites were associated with DAS28, ESR or CRP (p<0.05). Our study established an accurate prediction model

  16. Preoperative neutrophil response as a predictive marker of clinical outcome following open heart surgery and the impact of leukocyte filtration.

    LENUS (Irish Health Repository)

    Soo, Alan W

    2010-11-01

    Open heart surgery is associated with a massive systemic inflammatory response. Neutrophils, are the main mediator of this response. We hypothesised that the degree of neutrophil activation and inflammatory response to open heart surgery varies individually and correlates with clinical outcome. The aim of this study was to determine if individual clinical outcome can be predicted preoperatively through assessment of in-vitro stimulated neutrophil responses. Following that, the effects of neutrophil depletion through leukocyte filters are examined.

  17. Global DNA methylation is altered by neoadjuvant chemoradiotherapy in rectal cancer and may predict response to treatment - A pilot study.

    LENUS (Irish Health Repository)

    Tsang, J S

    2014-07-28

    In rectal cancer, not all tumours display a response to neoadjuvant treatment. An accurate predictor of response does not exist to guide patient-specific treatment. DNA methylation is a distinctive molecular pathway in colorectal carcinogenesis. Whether DNA methylation is altered by neoadjuvant treatment and a potential response predictor is unknown. We aimed to determine whether DNA methylation is altered by neoadjuvant chemoradiotherapy (CRT) and to determine its role in predicting response to treatment.

  18. Non-coding RNAs Enabling Prognostic Stratification and Prediction of Therapeutic Response in Colorectal Cancer Patients.

    Science.gov (United States)

    Perakis, Samantha O; Thomas, Joseph E; Pichler, Martin

    2016-01-01

    Colorectal cancer (CRC) is a heterogeneous disease and current treatment options for patients are associated with a wide range of outcomes and tumor responses. Although the traditional TNM staging system continues to serve as a crucial tool for estimating CRC prognosis and for stratification of treatment choices and long-term survival, it remains limited as it relies on macroscopic features and cases of surgical resection, fails to incorporate new molecular data and information, and cannot perfectly predict the variety of outcomes and responses to treatment associated with tumors of the same stage. Although additional histopathologic features have recently been applied in order to better classify individual tumors, the future might incorporate the use of novel molecular and genetic markers in order to maximize therapeutic outcome and to provide accurate prognosis. Such novel biomarkers, in addition to individual patient tumor phenotyping and other validated genetic markers, could facilitate the prediction of risk of progression in CRC patients and help assess overall survival. Recent findings point to the emerging role of non-protein-coding regions of the genome in their contribution to the progression of cancer and tumor formation. Two major subclasses of non-coding RNAs (ncRNAs), microRNAs and long non-coding RNAs, are often dysregulated in CRC and have demonstrated their diagnostic and prognostic potential as biomarkers. These ncRNAs are promising molecular classifiers and could assist in the stratification of patients into appropriate risk groups to guide therapeutic decisions and their expression patterns could help determine prognosis and predict therapeutic options in CRC. PMID:27573901

  19. An electrically actuated imperfect microbeam: Dynamical integrity for interpreting and predicting the device response

    KAUST Repository

    Ruzziconi, Laura

    2013-02-20

    In this study we deal with a microelectromechanical system (MEMS) and develop a dynamical integrity analysis to interpret and predict the experimental response. The device consists of a clamped-clamped polysilicon microbeam, which is electrostatically and electrodynamically actuated. It has non-negligible imperfections, which are a typical consequence of the microfabrication process. A single-mode reduced-order model is derived and extensive numerical simulations are performed in a neighborhood of the first symmetric natural frequency, via frequency response diagrams and behavior chart. The typical softening behavior is observed and the overall scenario is explored, when both the frequency and the electrodynamic voltage are varied. We show that simulations based on direct numerical integration of the equation of motion in time yield satisfactory agreement with the experimental data. Nevertheless, these theoretical predictions are not completely fulfilled in some aspects. In particular, the range of existence of each attractor is smaller in practice than in the simulations. This is because these theoretical curves represent the ideal limit case where disturbances are absent, which never occurs under realistic conditions. A reliable prediction of the actual (and not only theoretical) range of existence of each attractor is essential in applications. To overcome this discrepancy and extend the results to the practical case where disturbances exist, a dynamical integrity analysis is developed. After introducing dynamical integrity concepts, integrity profiles and integrity charts are drawn. They are able to describe if each attractor is robust enough to tolerate the disturbances. Moreover, they detect the parameter range where each branch can be reliably observed in practice and where, instead, becomes vulnerable, i.e. they provide valuable information to operate the device in safe conditions according to the desired outcome and depending on the expected disturbances

  20. Predicting species distribution and abundance responses to climate change : why it is essential to include biotic interactions across trophic levels

    NARCIS (Netherlands)

    Van der Putten, Wim H.; Macel, Mirka; Visser, Marcel E.

    2010-01-01

    Current predictions on species responses to climate change strongly rely on projecting altered environmental conditions on species distributions. However, it is increasingly acknowledged that climate change also influences species interactions. We review and synthesize literature information on biot

  1. Predicting species distribution and abundance responses to climate change: why it is essential to include biotic interactions across trophic levels

    NARCIS (Netherlands)

    Putten, van der W.H.; Macel, M.; Visser, de M.

    2010-01-01

    Current predictions on species responses to climate change strongly rely on projecting altered environmental conditions on species distributions. However, it is increasingly acknowledged that climate change also influences species interactions. We review and synthesize literature information on biot

  2. Applying dynamic parameters to predict hemodynamic response to volume expansion in spontaneously breathing patients with septic shock.

    Science.gov (United States)

    Lanspa, Michael J; Grissom, Colin K; Hirshberg, Eliotte L; Jones, Jason P; Brown, Samuel M

    2013-02-01

    Volume expansion is a mainstay of therapy in septic shock, although its effect is difficult to predict using conventional measurements. Dynamic parameters, which vary with respiratory changes, appear to predict hemodynamic response to fluid challenge in mechanically ventilated, paralyzed patients. Whether they predict response in patients who are free from mechanical ventilation is unknown. We hypothesized that dynamic parameters would be predictive in patients not receiving mechanical ventilation. This is a prospective, observational, pilot study. Patients with early septic shock and who were not receiving mechanical ventilation received 10-mL/kg volume expansion (VE) at their treating physician's discretion after initial resuscitation in the emergency department. We used transthoracic echocardiography to measure vena cava collapsibility index and aortic velocity variation before VE. We used a pulse contour analysis device to measure stroke volume variation (SVV). Cardiac index was measured immediately before and after VE using transthoracic echocardiography. Hemodynamic response was defined as an increase in cardiac index 15% or greater. Fourteen patients received VE, five of whom demonstrated a hemodynamic response. Vena cava collapsibility index and SVV were predictive (area under the curve = 0.83, 0.92, respectively). Optimal thresholds were calculated: vena cava collapsibility index, 15% or greater (positive predictive value, 62%; negative predictive value, 100%; P = 0.03); SVV, 17% or greater (positive predictive value 100%, negative predictive value 82%, P = 0.03). Aortic velocity variation was not predictive. Vena cava collapsibility index and SVV predict hemodynamic response to fluid challenge patients with septic shock who are not mechanically ventilated. Optimal thresholds differ from those described in mechanically ventilated patients.

  3. Mechanisms of frequency-specific responses of omega neuron 1 in crickets (Teleogryllus oceanicus): a polysynaptic pathway for song?

    Science.gov (United States)

    Faulkes, Z; Pollack, G S

    2001-04-01

    In crickets (Teleogryllus oceanicus), the auditory interneuron omega neuron 1 (ON1) responds to sounds over a wide range of frequencies but is most sensitive to the frequency of conspecific songs (4.5 kHz). Response latency is longest for this same frequency. We investigate the mechanisms that might account for the longer latency of ON1 to cricket-like sounds. Intracellular recordings revealed no evidence for appropriately timed postsynaptic inhibition of ON1 that might increase its latency, nor was latency affected by picrotoxin. The onset of excitatory postsynaptic potentials (EPSPs) was delayed for 4.5 kHz stimuli compared with ultrasound stimuli, pointing to a presynaptic locus for the latency difference. When ON1 is stimulated with high frequencies, discrete, apparently unitary EPSPs can be recorded in its dendrite, and these are latency-locked to spikes recorded simultaneously in the auditory nerve. This suggests that input to ON1 from high-frequency-tuned auditory receptor neurons is monosynaptic. In agreement with this, brief ultrasound stimuli evoke a single, short-latency EPSP in ON1. In contrast, the EPSP evoked by a brief 4.5 kHz stimulus consists of an early component, similar in latency to that evoked by ultrasound and possibly evoked by ultrasound-tuned receptors, and a later, dominant component. We interpret the early peak as arising from a monosynaptic afferent pathway and the late peak from a polysynaptic afferent pathway. Multiple-peak EPSPs, with timing similar to those evoked by sound stimuli, were also evoked by electrical stimulation of the auditory nerve.

  4. [{sup 18}F]FDG-PET predicts complete pathological response of breast cancer to neoadjuvant chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Berriolo-Riedinger, Alina; Touzery, Claude; Riedinger, Jean-Marc; Toubeau, Michel; Boichot, Christophe; Cochet, Alexandre [Centre Georges Francois Leclerc, Department of Nuclear Medicine, Dijon (France); Coudert, Bruno; Fumoleau, Pierre [Centre Georges Francois Leclerc, Department of Medical Oncology, Dijon (France); Arnould, Laurent [Centre Georges Francois Leclerc, Department of Pathology, Dijon (France); Brunotte, Francois [Centre Georges Francois Leclerc, Department of Nuclear Medicine, Dijon (France); CNRS UMR 5158, Dijon (France)

    2007-12-15

    To evaluate, in breast cancer patients treated by neoadjuvant chemotherapy, the predictive value of reduction in FDG uptake with regard to complete pathological response (pCR). Forty-seven women with non-metastatic, non-inflammatory, large or locally advanced breast cancer were included. Tumour uptake of FDG was evaluated before and after the first course of neoadjuvant chemotherapy. Four indices were used: maximal and average SUV without or with correction by body surface area and glycaemia (SUV{sub max}, SUV{sub avg}, SUV{sub max-BSA-G} and SUV{sub avg-BSA-G}, respectively). The predictive value of reduction in FDG uptake with respect to pCR was studied by logistic regression analysis. Relationships between baseline [{sup 18}F]FDG uptake and prognostic parameters were assessed. The relative decrease in FDG uptake ({delta}SUV) after the first course of neoadjuvant chemotherapy was significantly greater in the pCR group than in the non-pCR group (p < 0.000066). The four FDG uptake indices were all strongly correlated with each other. A decrease in SUV{sub max-BSA-G} of 85.4% {+-} 21.9% was found in pCR patients, versus 22.6% {+-} 36.6% in non-pCR patients. {delta}SUV{sub max-BSA-G} <-60% predicted the pCR with an accuracy of 87% and {delta}SUVs were found to be only factors predictive of the pCR at multivariate analysis. An elevated baseline SUV was associated with high mitotic activity (p < 0.0016), tumour grading (p < 0.004), high nuclear pleomorphism score (p < 0.03) and negative hormonal receptor status (p < 0.005). In breast cancer patients, after only one course of neoadjuvant chemotherapy the reduction in FDG uptake is an early and powerful predictor of pCR. (orig.)

  5. Prognostic and Predictive Biomarkers of Endocrine Responsiveness for Estrogen Receptor Positive Breast Cancer.

    Science.gov (United States)

    Ma, Cynthia X; Bose, Ron; Ellis, Matthew J

    2016-01-01

    The estrogen-dependent nature of breast cancer is the fundamental basis for endocrine therapy. The presence of estrogen receptor (ER), the therapeutic target of endocrine therapy, is a prerequisite for this therapeutic approach. However, estrogen-independent growth often exists de novo at diagnosis or develops during the course of endocrine therapy. Therefore ER alone is insufficient in predicting endocrine therapy efficacy. Several RNA-based multigene assays are now available in clinical practice to assess distant recurrence risk, with majority of these assays evaluated in patients treated with 5 years of adjuvant endocrine therapy. While MammaPrint and Oncotype Dx are most predictive of recurrence risk within the first 5 years of diagnosis, Prosigna, Breast Cancer Index (BCI), and EndoPredict Clin have also demonstrated utility in predicting late recurrence. In addition, PAM50, or Prosigna, provides further biological insights by classifying breast cancers into intrinsic molecular subtypes. Additional strategies are under investigation in prospective clinical trials to differentiate endocrine sensitive and resistant tumors and include on-treatment Ki-67 and Preoperative Endocrine Prognostic Index (PEPI) score in the setting of neoadjuvant endocrine therapy. These biomarkers have become important tools in clinical practice for the identification of low risk patients for whom chemotherapy could be avoided. However, there is much work ahead toward the development of a molecular classification that informs the biology and novel therapeutic targets in high-risk disease as chemotherapy has only modest benefit in this population. The recognition of somatic mutations and their relationship to endocrine therapy responsiveness opens important opportunities toward this goal. PMID:26987533

  6. Predicting the profile of nutrients available for absorption: from nutrient requirement to animal response and environmental impact

    OpenAIRE

    Dijkstra, J.; Kebreab, E.; Mills, J. A. N.; Pellikaan, W.F.; López, S; Bannink, A.; France, J

    2007-01-01

    Current feed evaluation systems for dairy cattle aim to match nutrient requirements with nutrient intake at pre-defined production levels. These systems were not developed to address, and are not suitable to predict, the responses to dietary changes in terms of production level and product composition, excretion of nutrients to the environment, and nutrition related disorders. The change from a requirement to a response system to meet the needs of various stakeholders requires prediction of t...

  7. Life-history traits predict perennial species response to fire in a desert ecosystem.

    Science.gov (United States)

    Shryock, Daniel F; DeFalco, Lesley A; Esque, Todd C

    2014-08-01

    The Mojave Desert of North America has become fire-prone in recent decades due to invasive annual grasses that fuel wildfires following years of high rainfall. Perennial species are poorly adapted to fire in this system, and post-fire shifts in species composition have been substantial but variable across community types. To generalize across a range of conditions, we investigated whether simple life-history traits could predict how species responded to fire. Further, we classified species into plant functional types (PFTs) based on combinations of life-history traits and evaluated whether these groups exhibited a consistent fire-response. Six life-history traits varied significantly between burned and unburned areas in short (up to 4 years) or long-term (up to 52 years) post-fire datasets, including growth form, lifespan, seed size, seed dispersal, height, and leaf longevity. Forbs and grasses consistently increased in abundance after fire, while cacti were reduced and woody species exhibited a variable response. Woody species were classified into three PFTs based on combinations of life-history traits. Species in Group 1 increased in abundance after fire and were characterized by short lifespans, small, wind-dispersed seeds, low height, and deciduous leaves. Species in Group 2 were reduced by fire and distinguished from Group 1 by longer lifespans and evergreen leaves. Group 3 species, which also decreased after fire, were characterized by long lifespans, large non-wind dispersed seeds, and taller heights. Our results show that PFTs based on life-history traits can reliably predict the responses of most species to fire in the Mojave Desert. Dominant, long-lived species of this region possess a combination of traits limiting their ability to recover, presenting a clear example of how a novel disturbance regime may shift selective environmental pressures to favor alternative life-history strategies. PMID:25247062

  8. Life-history traits predict perennial species response to fire in a desert ecosystem

    Science.gov (United States)

    Shryock, Daniel F.; DeFalco, Lesley A.; Esque, Todd C.

    2014-01-01

    The Mojave Desert of North America has become fire-prone in recent decades due to invasive annual grasses that fuel wildfires following years of high rainfall. Perennial species are poorly adapted to fire in this system, and post-fire shifts in species composition have been substantial but variable across community types. To generalize across a range of conditions, we investigated whether simple life-history traits could predict how species responded to fire. Further, we classified species into plant functional types (PFTs) based on combinations of life-history traits and evaluated whether these groups exhibited a consistent fire-response. Six life-history traits varied significantly between burned and unburned areas in short (up to 4 years) or long-term (up to 52 years) post-fire datasets, including growth form, lifespan, seed size, seed dispersal, height, and leaf longevity. Forbs and grasses consistently increased in abundance after fire, while cacti were reduced and woody species exhibited a variable response. Woody species were classified into three PFTs based on combinations of life-history traits. Species in Group 1 increased in abundance after fire and were characterized by short lifespans, small, wind-dispersed seeds, low height, and deciduous leaves. Species in Group 2 were reduced by fire and distinguished from Group 1 by longer lifespans and evergreen leaves. Group 3 species, which also decreased after fire, were characterized by long lifespans, large non-wind dispersed seeds, and taller heights. Our results show that PFTs based on life-history traits can reliably predict the responses of most species to fire in the Mojave Desert. Dominant, long-lived species of this region possess a combination of traits limiting their ability to recover, presenting a clear example of how a novel disturbance regime may shift selective environmental pressures to favor alternative life-history strategies.

  9. Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

    Directory of Open Access Journals (Sweden)

    Françoise eLecaignard

    2015-09-01

    Full Text Available Deviant stimuli, violating regularities in a sensory environment, elicit the Mismatch Negativity (MMN, largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities.

  10. A Comparison of Sales Response Predictions From Demand Models Applied to Store-Level versus Panel Data

    NARCIS (Netherlands)

    Andrews, Rick L.; Currim, Imran S.; Leeflang, Peter S. H.

    2011-01-01

    In order to generate sales promotion response predictions, marketing analysts estimate demand models using either disaggregated (consumer-level) or aggregated (store-level) scanner data. Comparison of predictions from these demand models is complicated by the fact that models may accommodate differe

  11. CADrx for GBM Brain Tumors: Predicting Treatment Response from Changes in Diffusion-Weighted MRI

    Directory of Open Access Journals (Sweden)

    Matthew S. Brown

    2009-11-01

    Full Text Available The goal of this study was to develop a computer-aided therapeutic response (CADrx system for early prediction of drug treatment response for glioblastoma multiforme (GBM brain tumors with diffusion weighted (DW MR images. In conventional Macdonald assessment, tumor response is assessed nine weeks or more post-treatment. However, we will investigate the ability of DW-MRI to assess response earlier, at five weeks post treatment. The apparent diffusion coefficient (ADC map, calculated from DW images, has been shown to reveal changes in the tumor’s microenvironment preceding morphologic tumor changes. ADC values in treated brain tumors could theoretically both increase due to the cell kill (and thus reduced cell density and decrease due to inhibition of edema. In this study, we investigated the effectiveness of features that quantify changes from pre- and post-treatment tumor ADC histograms to detect treatment response. There are three parts to this study: first, tumor regions were segmented on T1w contrast enhanced images by Otsu’s thresholding method, and mapped from T1w images onto ADC images by a 3D region of interest (ROI mapping tool using DICOM header information; second, ADC histograms of the tumor region were extracted from both pre- and five weeks post-treatment scans, and fitted by a two-component Gaussian mixture model (GMM. The GMM features as well as standard histogram-based features were extracted. Finally, supervised machine learning techniques were applied for classification of responders or non-responders. The approach was evaluated with a dataset of 85 patients with GBM under chemotherapy, in which 39 responded and 46 did not, based on tumor volume reduction. We compared adaBoost, random forest and support vector machine classification algorithms, using ten-fold cross validation, resulting in the best accuracy of 69.41% and the corresponding area under the curve (Az of 0.70.

  12. Universal response spectrum procedure for predicting walking-induced floor vibration

    Science.gov (United States)

    Brownjohn, James; Racic, Vitomir; Chen, Jun

    2016-03-01

    Floor vibrations caused by people walking are an important serviceability problem both for human occupants and vibration-sensitive equipment. Present design methodologies available for prediction of vibration response due to footfall loading are complex and suffer from division between low and high frequency floors. In order to simplify the design process and to avoid the problem of floor classification, this paper presents a methodology for predicting vibration response metrics due to pedestrian footfalls for any floor type having natural frequency in the range 1-20 Hz. Using a response spectrum approach, a database of 852 weight-normalised vertical ground reaction force (GRF) time histories recorded for more than 60 individuals walking on an instrumented treadmill was used to calculate response metrics. Chosen metrics were peak values of 1 s peak root-mean-square (RMS) acceleration and peak envelope one-third octave velocities. These were evaluated by weight-normalising the GRFs and applying to unit-mass single degree of freedom oscillators having natural frequencies in the range 1-20 Hz and damping ratios in the range 0.5-5%. Moreover, to account for effect of mode shape and duration of crossing (i.e. duration of dynamic loading), the recorded GRFs were applied for three most typical mode shapes and floor spans from 5 m to 40 m. The resulting peak values as functions of frequency i.e. spectra are condensed to statistical representations for chosen probability of being exceeded over a wide range of applications. RMS (acceleration) spectra show strong peaks corresponding to the first harmonic of pacing rate followed by clear minima at approximately 3.5 Hz, a second much smaller peak corresponding to the second harmonic and a steady decline with increasing frequency beginning around 5 Hz. One-third octave spectra show asymptotic trends with frequency, span and damping. A comprehensive validation exercise focusing on the acceleration RMS spectra was based on a

  13. Vibration Response Predictions for Heavy Panel Mounted Components from Panel Acreage Environment Specifications

    Science.gov (United States)

    Harrison, Phillip; Frady, Greg; Duvall, Lowery; Fulcher, Clay; LaVerde, Bruce

    2010-01-01

    The development of new launch vehicles in the Aerospace industry often relies on response measurements taken from previously developed vehicles during various stages of liftoff and ascent, and from wind tunnel models. These measurements include sound pressure levels, dynamic pressures in turbulent boundary layers and accelerations. Rigorous statistical scaling methods are applied to the data to derive new environments and estimate the performance of new skin panel structures. Scaling methods have proven to be reliable, particularly for designs similar to the vehicles used as the basis for scaling, and especially in regions of smooth acreage without exterior protuberances or heavy components mounted to the panel. To account for response attenuation of a panel-mounted component due to its apparent mass at higher frequencies, the vibroacoustics engineer often reduces the acreage vibration according to a weight ratio first suggested by Barrett. The accuracy of the reduction is reduced with increased weight of the panel-mounted component, and does not account for low-frequency amplification of the component/panel response as a system. A method is proposed that combines acreage vibration from scaling methods with finite element analysis to account for the frequency-dependent dynamics of heavy panel-mounted components. Since the acreage and mass-loaded skins respond to the same dynamic input pressure, such pressure may be eliminated in favor of a frequency-dependent scaling function applied to the acreage vibration to predict the mass-loaded panel response. The scaling function replaces the Barrett weight ratio, and contains all of the dynamic character of the loaded and unloaded skin panels. The solution simplifies for spatially uncorrelated and fully correlated input pressures. Since the prediction uses finite element models of the loaded and unloaded skins, a rich suite of response data are available to the design engineer, including interface forces, stress and strain

  14. Left ventricular 12 segmental strain imaging predicts response to cardiac resynchronization therapy

    Institute of Scientific and Technical Information of China (English)

    DONG Ying-xue; Jae K.Oh; YANG Yan-zong; Yong-mei Cha

    2013-01-01

    Background The number of non-responders to cardiac resynchronization therapy (CRT) exposes the need for better patient selection criteria for CRT.This study aimed to identify echocardiographic parameters that would predict the response to CRT.Methods Forty-five consecutive patients receiving CRT-D implantation for heart failure (HF) were included in this prospective study.New York Heart Association (NYHA) class,6-minute walk distance,electrograph character,and multi echocardiographic parameters,especially in strain patterns,were measured and compared before and six months after CRT in the responder and non-responder groups.Response to CRT was defined as a decrease in left ventricular endsystolic volume (LVESV) of 15% or more at 6-month follow up.Results Twenty-two (48.9%) patients demonstrated a response to CRT at 6-month follow-up.Significant improvement in NYHA class (P <0.01),left ventricular end-diastolic volume (LVEDV) (P <0.01),and 6-minute walk distance (P <0.01) was shown in this group.Although there was an interventricular mechanical delay determined by the difference between left and right ventricular pre-ejection intervals ((42.87±19.64) ms vs.(29.43±18.19) ms,P=0.02),the standard deviation of time to peak myocardial strain among 12 basal,mid and apical segments (Tε-SD) ((119.97±43.32) ms vs.(86.62±36.86) ms,P=0.01) and the non-ischemic etiology (P=0.03) were significantly higher in responders than non-responders,only the Tε-SD (OR=1.02,95% Cl=1.01-1.04,P=0.02) proved to be a favorable predictor of CRT response after multivariate Logistic regression analysis.Conclusion The left ventricular 12 segmental strain imaging is a promising echocardiographic parameter for predicting CRT response.

  15. Interleukin-10 promoter polymorphism predicts initial response of chronic hepatitis B to interferon alfa

    Directory of Open Access Journals (Sweden)

    Ma Weimin

    2011-01-01

    Full Text Available Abstract In order to examine whether variation in interleukin-10 promoter polymorphism would predict the likelihood of sustain response of chronic hepatitis B to treatment with interferon alfa (IFN-α, the inheritance of 3 biallelic polymorphisms in the IL-10 gene promoter in patients with 52 chronic hepatitis B were determined by polymerase chain reaction (PCR-bared techniques, restriction enzyme digestion or direct sequencing. The relationship to the outcome of antiviral therapy for chronic HBV infection was studied in 24 patients who had a virologically sustained response(SR and in 28 non-responder(NR to interferon alfa-2b and several IL-10 variants were more frequent among SR compared with NR. Carriage of the -592A allele, -592A/A genotype and -1082/-1819/-592 ATA haplotype was associated with SR. Our findings indicate that heterogeneity in the promoter region of the IL-10 gene has a role in determining the initial response of chronic hepatitis B to IFN-α therapy.

  16. Xenobiotic metabolizing enzyme gene polymorphisms predict response to lung volume reduction surgery

    Directory of Open Access Journals (Sweden)

    DeMeo Dawn L

    2007-08-01

    Full Text Available Abstract Background In the National Emphysema Treatment Trial (NETT, marked variability in response to lung volume reduction surgery (LVRS was observed. We sought to identify genetic differences which may explain some of this variability. Methods In 203 subjects from the NETT Genetics Ancillary Study, four outcome measures were used to define response to LVRS at six months: modified BODE index, post-bronchodilator FEV1, maximum work achieved on a cardiopulmonary exercise test, and University of California, San Diego shortness of breath questionnaire. Sixty-four single nucleotide polymorphisms (SNPs were genotyped in five genes previously shown to be associated with chronic obstructive pulmonary disease susceptibility, exercise capacity, or emphysema distribution. Results A SNP upstream from glutathione S-transferase pi (GSTP1; p = 0.003 and a coding SNP in microsomal epoxide hydrolase (EPHX1; p = 0.02 were each associated with change in BODE score. These effects appeared to be strongest in patients in the non-upper lobe predominant, low exercise subgroup. A promoter SNP in EPHX1 was associated with change in BODE score (p = 0.008, with the strongest effects in patients with upper lobe predominant emphysema and low exercise capacity. One additional SNP in GSTP1 and three additional SNPs in EPHX1 were associated (p Conclusion Genetic variants in GSTP1 and EPHX1, two genes encoding xenobiotic metabolizing enzymes, were predictive of response to LVRS. These polymorphisms may identify patients most likely to benefit from LVRS.

  17. Shy birds play it safe: personality in captivity predicts risk responsiveness during reproduction in the wild.

    Science.gov (United States)

    Cole, Ella F; Quinn, John L

    2014-05-01

    Despite a growing body of evidence linking personality to life-history variation and fitness, the behavioural mechanisms underlying these relationships remain poorly understood. One mechanism thought to play a key role is how individuals respond to risk. Relatively reactive and proactive (or shy and bold) personality types are expected to differ in how they manage the inherent trade-off between productivity and survival, with bold individuals being more risk-prone with lower survival probability, and shy individuals adopting a more risk-averse strategy. In the great tit (Parus major), the shy-bold personality axis has been well characterized in captivity and linked to fitness. Here, we tested whether 'exploration behaviour', a captive assay of the shy-bold axis, can predict risk responsiveness during reproduction in wild great tits. Relatively slow-exploring (shy) females took longer than fast-exploring (bold) birds to resume incubation after a novel object, representing an unknown threat, was attached to their nest-box, with some shy individuals not returning within the 40 min trial period. Risk responsiveness was consistent within individuals over days. These findings provide rare, field-based experimental evidence that shy individuals prioritize survival over reproductive investment, supporting the hypothesis that personality reflects life-history variation through links with risk responsiveness. PMID:24829251

  18. Infrared spectra of primary melanomas can predict response to chemotherapy: The example of dacarbazine.

    Science.gov (United States)

    Wald, N; Le Corre, Y; Martin, L; Mathieu, V; Goormaghtigh, E

    2016-02-01

    Metastatic melanomas are highly aggressive and median survival is 6-9months for stage IV patients in the absence of treatment with anti-tumor activity. Dacarbazine is an alkylating agent that has been widely used in the treatment of metastatic melanomas and that could be still used in combination with targeted or immune therapies. Indeed, therapeutic benefits of these treatments in monotherapy are poor and one option to improve them is to combine drugs and/or to better anticipate the individual response to a defined treatment. To our best knowledge and to date, there is no test available to predict the response of a patient to dacarbazine. We show here that examination of melanoma histological sections by infrared micro-spectroscopy reveals the sensitivity of the cancer to dacarbazine. Unsupervised analysis of the FTIR spectra evidences spontaneous and significant clustering of infrared spectra into two groups that match the clinical responsiveness of the patients to dacarbazine used as a first-line treatment. A supervised model resulted in 83% of the patient status (responder/non-responder) being correctly identified. The spectra revealed a key modification in the nature and quantity of lipids in the cells of both groups. PMID:26577766

  19. Immune response genes and pathogen presence predict migration survival in wild salmon smolts.

    Science.gov (United States)

    Jeffries, Ken M; Hinch, Scott G; Gale, Marika Kirstin; Clark, Timothy D; Lotto, Andrew G; Casselman, Matthew T; Li, Shaorong; Rechisky, Erin L; Porter, Aswea D; Welch, David W; Miller, Kristina M

    2014-12-01

    We present the first data to link physiological responses and pathogen presence with subsequent fate during migration of wild salmonid smolts. We tagged and non-lethally sampled gill tissue from sockeye salmon (Oncorhynchus nerka) smolts as they left their nursery lake (Chilko Lake, BC, Canada) to compare gene expression profiles and freshwater pathogen loads with migration success over the first ~1150 km of their migration to the North Pacific Ocean using acoustic telemetry. Fifteen per cent of smolts were never detected again after release, and these fish had gene expression profiles consistent with an immune response to one or more viral pathogens compared with fish that survived their freshwater migration. Among the significantly upregulated genes of the fish that were never detected postrelease were MX (interferon-induced GTP-binding protein Mx) and STAT1 (signal transducer and activator of transcription 1-alpha/beta), which are characteristic of a type I interferon response to viral pathogens. The most commonly detected pathogen in the smolts leaving the nursery lake was infectious haematopoietic necrosis virus (IHNV). Collectively, these data show that some of the fish assumed to have died after leaving the nursery lake appeared to be responding to one or more viral pathogens and had elevated stress levels that could have contributed to some of the mortality shortly after release. We present the first evidence that changes in gene expression may be predictive of some of the freshwater migration mortality in wild salmonid smolts. PMID:25354752

  20. Shaking table test and dynamic response prediction on an earthquake-damaged RC building

    Institute of Scientific and Technical Information of China (English)

    叶献国; 钱嫁茹; 李康宁

    2004-01-01

    This paper presents the results from shaking table tests of a one-tenth-scale reinforced concrete (RC) building model. The test model is a protype of a building that was seriously damaged during the 1985 Mexico earthquake. The input ground excitation used during the test was from the records obtained near the site of the prototype building during the 1985 and 1995 Mexico earthquakes. The tests showed that the damage pattern of the test model agreed well with that of the prototype building. Analytical prediction of earthquake response has been conducted for the prototype building using a sophisticated 3-D frame model. The input motion used for the dynamic analysis was the shaking table test measurements with similarity transformation. The comparison of the analytical results and the shaking table test results indicates that the response of the RC building to minor and the moderate earthquakes can be predicated well. However, there is difference between the predication and the actual response to the major earthquake.

  1. A method for predicting full scale buffet response with rigid wind tunnel model fluctuating pressure data. Volume 1: Prediction method development and assessment

    Science.gov (United States)

    Cunningham, A. M., Jr.; Benepe, D. B.; Watts, D.; Waner, P. G.

    1978-01-01

    The method requires unsteady aerodynamic forces, natural airplane modes, and the measured pressure data as input. A gust response computer program is used to calculate buffet response due to the forcing function posed by the measured pressure data. By calculating both symmetric and antisymmetric solutions, upper and lower bounds on full-scale buffet response are formed. Comparisons of predictions with flight test results are made and the effects of horizontal tail loads and static aeroelasticity are shown. Discussions are also presented on the effects of primary wing torsion modes, chordwise and spanwise phase angles, and altitude.

  2. Quantitation of HBsAg predicts response to entecavir therapy in HBV genotype C patients

    Institute of Scientific and Technical Information of China (English)

    Etsuro Orito; Kei Fujiwara; Hiroshi Kanie; Tesshin Ban; Tomonori Yamada; Katsumi Hayashi

    2012-01-01

    AIM:To analysis the factors that predict the response to entecavir therapy in chronic hepatitis patients with hepatitis B virus (HBV) genotype C.METHODS:Fifty patients [hepatitis B e antigen (HBeAg)-negative:HBeAg-positive =26:24] with HBV genotype C,who received na(i)ve entecavir therapy for > 2 years,were analyzed.Patients who showed HBV DNA levels ≥3.0 log viral copies/mL after 2 years of entecavir therapy were designated as slow-responders,while those that showed < 3.0 log copies/mL were termed rapidresponders.Quantitative hepatitis B surface antigen (HBsAg) levels (qHBsAg) were determined by the Architect HBsAg QT immunoassay.Hepatitis B core-related antigen was detected by enzyme immunoassay.Pre-C and Core promoter mutations were determined using by polymerase chain reaction (PCR).Drug-resistance mutations were detected by the PCR-Invader method.RESULTS:At year 2,HBV DNA levels in all patients in the HBeAg-negative group were < 3.0 log copies/mL.In contrast,in the HBeAg-positive group,41.7% were slow-responders,while 58.3% were rapid-responders.No entecavir-resistant mutants were detected in the slow-responders.When the pretreatment factors were compared between the slow-and rapid-responders;the median qHBsAg in the slow-responders was 4.57log IU/mL,compared with 3.63 log IU/mL in the rapidresponders (P < 0.01).When the pretreatment factors predictive of HBV DNA-negative status at year 2 in all 50 patients were analyzed,HBeAg-negative status,low HBV DNA levels,and low qHBsAg levels were significant (P < 0.01).Multivariate analysis revealed that the low qHBsAg level was the most significant predictive factor (P =0.03).CONCLUSION:Quantitation of HBsAg could be a useful indicator to predict response to entecavir therapy.

  3. Characterization of DNAPL Source Zone Architecture and Prediction of Associated Plume Response: Progress and Perspectives

    Science.gov (United States)

    Abriola, L. M.; Pennell, K. D.; Ramsburg, C. A.; Miller, E. L.; Christ, J.; Capiro, N. L.; Mendoza-Sanchez, I.; Boroumand, A.; Ervin, R. E.; Walker, D. I.; Zhang, H.

    2012-12-01

    It is now widely recognized that the distribution of contaminant mass will control both the evolution of aqueous phase plumes and the effectiveness of many source zone remediation technologies at sites contaminated by dense nonaqueous phase liquids (DNAPLs). Advances in the management of sites containing DNAPL source zones, however, are currently hampered by the difficulty associated with characterizing subsurface DNAPL 'architecture'. This presentation provides an overview of recent research, integrating experimental and mathematical modeling studies, designed to improve our ability to characterize DNAPL distributions and predict associated plume response. Here emphasis is placed on estimation of the most information-rich DNAPL architecture metrics, through a combination of localized in situ tests and more readily available plume transect concentration observations. Estimated metrics will then serve as inputs to an upscaled screening model for prediction of long term plume response. Machine learning techniques were developed and refined to identify a variety of source zone metrics and associated confidence intervals through the processing of down gradient concentration data. Estimated metrics include the volumes and volume percentages of DNAPL in pools and ganglia, as well as their ratio (pool fraction). Multiphase flow and transport simulations provided training data for model development and assessment that are representative of field-scale DNAPL source zones and their evolving plumes. Here, a variety of release and site heterogeneity (sequential Gaussian permeability) conditions were investigated. Push-pull tracer tests were also explored as a means to provide localized in situ observations to refine these metric estimates. Here, two-dimensional aquifer cell experiments and mathematical modeling were used to quantify upscaled interphase mass transfer rates and the interplay between injection and extraction rates, local source zone architecture, and tracer

  4. Locally advanced rectal cancer: Value of ADC mapping in prediction of tumor response to radiochemotherapy

    International Nuclear Information System (INIS)

    Purpose: To evaluate the diagnostic performance of quantitative apparent diffusion coefficient (ADC) measurements, in the assessment of the therapeutic response to chemo-radiation therapy (CRT) in patients with locally advanced rectal cancer, by analyzing post CRT values of ADC, in relation to tumor regression grade (TRG) obtained by histopathologic evaluation of the rectal specimen. Methods: This prospective study was approved by an Institutional Review Board, and informed consent was obtained from all patients. Thirty-one patients with locally advanced rectal cancer underwent pre and post CRT MR imaging at 1.5 T. ADC values were measured in regions of interest (ROIs) drawn independently by two radiologists, blinded to the pathology results, on three slices of the pre and post CRT DW-MR image sets with the corresponding T2 weighted images (T2WI) available for anatomic reference. The two readers’ measurements were compared for differences in ADC values, inter-observer variability (measured as the intraclass correlation coefficient; ICC) and the ADC distributions of responders vs non-responders. The diagnostic performance of ADC in the prediction of the response to CRT was evaluated by calculating the area under the ROC curve (AUC) and the optimal cut-off values. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were assessed. Results: The two readers showed an overall strong agreement in measuring ADC values. For both readers, no differences in ADC pre-treatment measurements were observed between responders and non-responders. For reader 1, the post-CRT ADC and the ΔADC presented the higher AUC (0.823 and 0.803, respectively), while Δ%ADC provided the lower AUC value (0.682). The optimal cutoff point was 1.294 s/mm2 for post-CRT measures (sensitivity = 86.4%, specificity = 66.7%, PPV = 86.4%, NPV = 66.7%), 0.500 for ΔADC (sensitivity = 81.8%, specificity = 66.7%, PPV = 85.7%, NPV = 60.0%) and 59.3% for

  5. An Analytical Model for the Prediction of a Micro-Dosimeter Response Function

    Science.gov (United States)

    Badavi, Francis F.; Xapsos, Mike

    2008-01-01

    A rapid analytical procedure for the prediction of a micro-dosimeter response function in low Earth orbit (LEO), correlated with the Space Transportation System (STS, shuttle) Tissue Equivalent Proportional Counter (TEPC) measurements is presented. The analytical model takes into consideration the energy loss straggling and chord length distribution of the detector, and is capable of predicting energy deposition fluctuations in a cylindrical micro-volume of arbitrary aspect ratio (height/diameter) by incoming ions through both direct and indirect (ray) events. At any designated (ray traced) target point within the vehicle, the model accepts the differential flux spectrum of Galactic Cosmic Rays (GCR) and/or trapped protons at LEO as input. On a desktop PC, the response function of TEPC for each ion in the GCR/trapped field is computed at the average rate of 30 seconds/ion. The ionizing radiation environment at LEO is represented by O'Neill fs GCR model (2004), covering charged particles in the 1 less than or equal to Z less than or equal to 28. O'Neill's free space GCR model is coupled with the Langley Research Center (LaRC) angular dependent geomagnetic cutoff model to compute the transmission coefficient in LEO. The trapped proton environment is represented by a LaRC developed time dependent procedure which couples the AP8MIN/AP8MAX, Deep River Neutron Monitor (DRNM) and F10.7 solar radio frequency measurements. The albedo neutron environment is represented by the extrapolation of the Atmospheric Ionizing Radiation (AIR) measurements. The charged particle transport calculations correlated with STS 51 and 114 flights are accomplished by using the most recent version (2005) of the LaRC deterministic High charge (Z) and Energy TRaNsport (HZETRN) code. We present the correlations between the TEPC model predictions (response function) and TEPC measured differential/integral spectra in the lineal energy (y) domain for both GCR and trapped protons, with the conclusion

  6. Local predation pressure predicts the strength of mobbing responses in tropical birds

    Institute of Scientific and Technical Information of China (English)

    Luis SANDOVAL; David R.WILSON

    2012-01-01

    Many birds join cooperative mobbing aggregations and collectively harass predators.Individuals participating in these ephemeral associations benefit by deterring the predator,but also incur energetic costs and increased risk of predation.Explaining the evolution of mobbing is challenging because individuals could prevail by selfishly seeking safety while allowing others to mob.An important step in understanding the evolution of mobbing is to identify factors affecting its expression.The ecological constraints model suggests that animals are more likely to cooperate under adverse environmental conditions,such as when local predation pressure is high.We tested this prediction by comparing the mobbing responses of several species of birds to the local abundance of their primary predator,the ferruginous pygmy-owl Glaucidium brasilianum.We used acoustic playback to elicit mobbing responses in environments where owls were common,uncommon,or rare.Stimuli were either the song of a ferruginous pygmy-owl or the mobbing calls of three of the owl's common prey species.During each playback,we characterized mobbing responses by noting the number of species and individuals that approached the loudspeaker,as well as the closest approach by any bird.Mobbing responses to both stimuli were strong in locations where Ferruginous Pygmy-owls were common,intermediate where owls were uncommon,and weak where they were rare.This pattern persisted even after controlling for differences in species richness and composition among the three environments.Results support the ecological constraints model and provide strong evidence that intense predation pressure increases the expression of cooperative mobbing in tropical birds.

  7. Local predation pressure predicts the strength of mobbing responses in tropical birds

    Directory of Open Access Journals (Sweden)

    Luis SANDOVAL, David R. WILSON

    2012-10-01

    Full Text Available Many birds join cooperative mobbing aggregations and collectively harass predators. Individuals participating in these ephemeral associations benefit by deterring the predator, but also incur energetic costs and increased risk of predation. Explaining the evolution of mobbing is challenging because individuals could prevail by selfishly seeking safety while allowing others to mob. An important step in understanding the evolution of mobbing is to identify factors affecting its expression. The ecological constraints model suggests that animals are more likely to cooperate under adverse environmental conditions, such as when local predation pressure is high. We tested this prediction by comparing the mobbing responses of several species of birds to the local abundance of their primary predator, the ferruginous pygmy-owl Glaucidium brasilianum. We used acoustic playback to elicit mobbing responses in environments where owls were common, uncommon, or rare. Stimuli were either the song of a ferruginous pygmy-owl or the mobbing calls of three of the owl’s common prey species. During each playback, we characterized mobbing responses by noting the number of species and individuals that approached the loudspeaker, as well as the closest approach by any bird. Mobbing responses to both stimuli were strong in locations where Ferruginous Pygmy-owls were common, intermediate where owls were uncommon, and weak where they were rare. This pattern persisted even after controlling for differences in species richness and composition among the three environments. Results support the ecological constraints model and provide strong evidence that intense predation pressure increases the expression of cooperative mobbing in tropical birds [Current Zoology 58 (5: 781-790, 2012].

  8. DNA Repair Biomarkers Predict Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, Brian M., E-mail: bmalexander@lroc.harvard.edu [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, Massachusetts (United States); Wang Xiaozhe [On-Q-ity, Inc., Waltham, Massachusetts (United States); Niemierko, Andrzej [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Weaver, David T. [On-Q-ity, Inc., Waltham, Massachusetts (United States); Mak, Raymond H. [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Cancer Center, Boston, Massachusetts (United States); Roof, Kevin S. [Southeast Radiation Oncology, Charlotte, North Carolina (United States); Fidias, Panagiotis [Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts (United States); Wain, John [Department of Surgery, Massachusetts General Hospital, Boston, Massachusetts (United States); Choi, Noah C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2012-05-01

    Purpose: The addition of neoadjuvant chemoradiotherapy prior to surgical resection for esophageal cancer has improved clinical outcomes in some trials. Pathologic complete response (pCR) following neoadjuvant therapy is associated with better clinical outcome in these patients, but only 22% to 40% of patients achieve pCR. Because both chemotherapy and radiotherapy act by inducing DNA damage, we analyzed proteins selected from multiple DNA repair pathways, using quantitative immunohistochemistry coupled with a digital pathology platform, as possible biomarkers of treatment response and clinical outcome. Methods and Materials: We identified 79 patients diagnosed with esophageal cancer between October 1994 and September 2002, with biopsy tissue available, who underwent neoadjuvant chemoradiotherapy prior to surgery at the Massachusetts General Hospital and used their archived, formalin-fixed, paraffin-embedded biopsy samples to create tissue microarrays (TMA). TMA sections were stained using antibodies against proteins in various DNA repair pathways including XPF, FANCD2, PAR, MLH1, PARP1, and phosphorylated MAPKAP kinase 2 (pMK2). Stained TMA slides were evaluated using machine-based image analysis, and scoring incorporated both the intensity and the quantity of positive tumor nuclei. Biomarker scores and clinical data were assessed for correlations with clinical outcome. Results: Higher scores for MLH1 (p = 0.018) and lower scores for FANCD2 (p = 0.037) were associated with pathologic response to neoadjuvant chemoradiation on multivariable analysis. Staining of MLH1, PARP1, XPF, and PAR was associated with recurrence-free survival, and staining of PARP1 and FANCD2 was associated with overall survival on multivariable analysis. Conclusions: DNA repair proteins analyzed by immunohistochemistry may be useful as predictive markers for response to neoadjuvant chemoradiotherapy in patients with esophageal cancer. These results are hypothesis generating and need

  9. Power Prediction Model for Turning EN-31 Steel Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    M. Hameedullah

    2010-01-01

    Full Text Available Power consumption in turning EN-31 steel (a material that is most extensively used in automotive industry with tungstencarbide tool under different cutting conditions was experimentally investigated. The experimental runs were planned accordingto 24+8 added centre point factorial design of experiments, replicated thrice. The data collected was statisticallyanalyzed using Analysis of Variance technique and first order and second order power consumption prediction models weredeveloped by using response surface methodology (RSM. It is concluded that second-order model is more accurate than thefirst-order model and fit well with the experimental data. The model can be used in the automotive industries for decidingthe cutting parameters for minimum power consumption and hence maximum productivity

  10. Kalman filtering for neural prediction of response spectra from mining tremors

    Energy Technology Data Exchange (ETDEWEB)

    Krok, A.; Waszczyszyn, Z. [Cracow University of Technology, Krakow (Poland)

    2007-08-15

    Acceleration response spectra (ARS) for mining tremors in the Upper Silesian Coalfield, Poland are generated using neural networks trained by means of Kalman filtering. The target ARS were computed on the base of measured accelerograms. It was proved that the standard feed-forward, layered neural network, trained by the DEFK (decoupled extended Kalman filter) algorithm is numerically much less efficient than the standard recurrent NN learnt by Recurrent DEKF, cf. (Haykin S, (editor). Kalman filtering and neural networks. New York: John Wiley & Sons; 2001). It is also shown that the studied KF algorithms are better than the traditional Resilient-Propagation learning method. The improvement of the training process and neural prediction due to introduction of an autoregressive input is also discussed in the paper.

  11. Quitting smoking : The importance of non-smoker identity in predicting smoking behaviour and responses to a smoking ban

    NARCIS (Netherlands)

    Meijer, Eline; Gebhardt, Winifred A.; Dijkstra, Arie; Willemsen, Marc C.; Van Laar, Colette

    2015-01-01

    Objective: We examined how smoker' and non-smoker' self- and group-identities and socio-economic status (SES) may predict smoking behaviour and responses to antismoking measures (i.e. the Dutch smoking ban in hospitality venues). We validated a measure of responses to the smoking ban.Design: Longitu

  12. Pretreatment Growth Rate Predicts Radiation Response in Vestibular Schwannomas

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Nina N. [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); Harvard Medical School, Department of Medicine, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Niemierko, Andrzej [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); Larvie, Mykol [Harvard Medical School, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States); Curtin, Hugh [Harvard Medical School, Department of Radiology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts (United States); Loeffler, Jay S. [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States); McKenna, Michael J. [Harvard Medical School, Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts (United States); Shih, Helen A., E-mail: hshih@partners.org [Department of Radiation Oncology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2014-05-01

    Purpose: Vestibular schwannomas (VS) are often followed without initial therapeutic intervention because many tumors do not grow and radiation therapy is associated with potential adverse effects. In an effort to determine whether maximizing initial surveillance predicts for later treatment response, the predictive value of preirradiation growth rate of VS on response to radiation therapy was assessed. Methods and Materials: Sixty-four patients with 65 VS were treated with single-fraction stereotactic radiation surgery or fractionated stereotactic radiation therapy. Pre- and postirradiation linear expansion rates were estimated using volumetric measurements on sequential magnetic resonance images (MRIs). In addition, postirradiation tumor volume change was classified as demonstrating shrinkage (ratio of volume on last follow-up MRI to MRI immediately preceding irradiation <80%), stability (ratio 80%-120%), or expansion (ratio >120%). The median pre- and postirradiation follow-up was 20.0 and 27.5 months, respectively. Seven tumors from neurofibromatosis type 2 (NF2) patients were excluded from statistical analyses. Results: In the 58 non-NF2 patients, there was a trend of correlation between pre- and postirradiation volume change rates (slope on linear regression, 0.29; P=.06). Tumors demonstrating postirradiation expansion had a median preirradiation growth rate of 89%/year, and those without postirradiation expansion had a median preirradiation growth rate of 41%/year (P=.02). As the preirradiation growth rate increased, the probability of postirradiation expansion also increased. Overall, 24.1% of tumors were stable, 53.4% experienced shrinkage, and 22.5% experienced expansion. Predictors of no postirradiation tumor expansion included no prior surgery (P=.01) and slower tumor growth rate (P=.02). The control of tumors in NF2 patients was only 43%. Conclusions: Radiation therapy is an effective treatment for VS, but tumors that grow quickly preirradiation may be

  13. Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails

    Science.gov (United States)

    Xu, Meng; Mu, Xidong; Dick, Jaimie T. A.; Fang, Miao; Gu, Dangen; Luo, Du; Zhang, Jiaen; Luo, Jianren; Hu, Yinchang

    2016-01-01

    Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs) of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in “100 of the World's Worst Invasive Alien Species”; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest “attack rates” a, shortest “handling times” h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach. PMID:26771658

  14. Doppler laser imaging predicts response to topical minoxidil in the treatment of female pattern hair loss.

    Science.gov (United States)

    McCoy, J; Kovacevic, M; Situm, M; Stanimirovic, A; Bolanca, Z; Goren, A

    2016-01-01

    Topical minoxidil is the only drug approved by the US FDA for the treatment of female pattern hair loss. Unfortunately, following 16 weeks of daily application, less than 40% of patients regrow hair. Several studies have demonstrated that sulfotransferase enzyme activity in plucked hair follicles predicts topical minoxidil response in female pattern hair loss patients. However, due to patients’ discomfort with the procedure, and the time required to perform the enzymatic assay it would be ideal to develop a rapid, non-invasive test for sulfotransferase enzyme activity. Minoxidil is a pro-drug converted to its active form, minoxidil sulfate, by sulfotransferase enzymes in the outer root sheath of hair. Minoxidil sulfate is the active form required for both the promotion of hair regrowth and the vasodilatory effects of minoxidil. We thus hypothesized that laser Doppler velocimetry measurement of scalp blood perfusion subsequent to the application of topical minoxidil would correlate with sulfotransferase enzyme activity in plucked hair follicles. In this study, plucked hair follicles from female pattern hair loss patients were analyzed for sulfotransferase enzyme activity. Additionally, laser Doppler velocimetry was used to measure the change in scalp perfusion at 15, 30, 45, and 60 minutes, after the application of minoxidil. In agreement with our hypothesis, we discovered a correlation (r=1.0) between the change in scalp perfusion within 60 minutes after topical minoxidil application and sulfotransferase enzyme activity in plucked hairs. To our knowledge, this is the first study demonstrating the feasibility of using laser Doppler imaging as a rapid, non-invasive diagnostic test to predict topical minoxidil response in the treatment of female pattern hair loss. PMID:27049083

  15. Behavioural stress responses predict environmental perception in European sea bass (Dicentrarchus labrax.

    Directory of Open Access Journals (Sweden)

    Sandie Millot

    Full Text Available Individual variation in the response to environmental challenges depends partly on innate reaction norms, partly on experience-based cognitive/emotional evaluations that individuals make of the situation. The goal of this study was to investigate whether pre-existing differences in behaviour predict the outcome of such assessment of environmental cues, using a conditioned place preference/avoidance (CPP/CPA paradigm. A comparative vertebrate model (European sea bass, Dicentrarchus labrax was used, and ninety juvenile individuals were initially screened for behavioural reactivity using a net restraining test. Thereafter each individual was tested in a choice tank using net chasing as aversive stimulus or exposure to familiar conspecifics as appetitive stimulus in the preferred or non preferred side respectively (called hereafter stimulation side. Locomotor behaviour (i.e. time spent, distance travelled and swimming speed in each tank side of each individual was recorded and analysed with video software. The results showed that fish which were previously exposed to appetitive stimulus increased significantly the time spent on the stimulation side, while aversive stimulus led to a strong decrease in time spent on the stimulation side. Moreover, this study showed clearly that proactive fish were characterised by a stronger preference for the social stimulus and when placed in a putative aversive environment showed a lower physiological stress responses than reactive fish. In conclusion, this study showed for the first time in sea bass, that the CPP/CPA paradigm can be used to assess the valence (positive vs. negative that fish attribute to different stimuli and that individual behavioural traits is predictive of how stimuli are perceived and thus of the magnitude of preference or avoidance behaviour.

  16. MRI evaluation of anterior knee pain: predicting response to nonoperative treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wittstein, Jocelyn R.; Garrett, William E. [Duke University Medical Center, Division of Orthopaedic Surgery, Durham, NC (United States); O' Brien, Seth D. [Brooke Army Medical Center, Department of Radiology, San Antonio, TX (United States); Vinson, Emily N. [Duke University Medical Center, Department of Radiology, Durham, NC (United States)

    2009-09-15

    Tibial tubercle lateral deviation and patellofemoral chondromalacia are associated with anterior knee pain (AKP). We hypothesized that increased tibial tubercle lateral deviation and patellofemoral chondromalacia on magnetic resonance imaging correlates with the presence of AKP and with failure of nonoperative management. In this retrospective comparative study, a blinded musculoskeletal radiologist measured tibial tubercle lateral deviation relative to the trochlear groove in 15 controls, 15 physical therapy responders with AKP, and 15 physical therapy nonresponders with AKP. Patellar and trochlear cartilage was assessed for signal abnormality, irregularity, and defects. The mean tibial tubercle lateral deviation in controls, physical therapy responders, and physical therapy nonresponders were 9.32 {+-} 0.68, 13.01 {+-} 0.82, and 16.07 {+-} 1.16 mm, respectively (data are mean {+-} standard deviation). The correlation coefficients for tubercle deviation, chondromalacia patellae, and trochlear chondromalacia were 0.51 (P < 0.01), 0.44 (P < 0.01), and 0.28 (P < 0.05), respectively. On analysis of variance, tubercle deviation and chondromalacia patellae contributed significantly to prediction of AKP and response to physical therapy. The presence of chondromalacia patellae and a tubercle deviation greater than 14.6 mm is 100% specific and 67% sensitive with a positive predictive value of 100% and negative predictive value of 75% for failure of nonoperative management. Subjects with AKP have more laterally positioned tibial tubercles and are more likely to have patellar chondromalacia. Patients with AKP, chondromalacia patellae, and a tubercle deviation greater than 14.6 mm are unlikely to respond to nonoperative treatment. Knowledge of tibial tubercle lateralization and presence of chondromalacia patellae may assist clinicians in determining patient prognosis and selecting treatment options. (orig.)

  17. MRI evaluation of anterior knee pain: predicting response to nonoperative treatment

    International Nuclear Information System (INIS)

    Tibial tubercle lateral deviation and patellofemoral chondromalacia are associated with anterior knee pain (AKP). We hypothesized that increased tibial tubercle lateral deviation and patellofemoral chondromalacia on magnetic resonance imaging correlates with the presence of AKP and with failure of nonoperative management. In this retrospective comparative study, a blinded musculoskeletal radiologist measured tibial tubercle lateral deviation relative to the trochlear groove in 15 controls, 15 physical therapy responders with AKP, and 15 physical therapy nonresponders with AKP. Patellar and trochlear cartilage was assessed for signal abnormality, irregularity, and defects. The mean tibial tubercle lateral deviation in controls, physical therapy responders, and physical therapy nonresponders were 9.32 ± 0.68, 13.01 ± 0.82, and 16.07 ± 1.16 mm, respectively (data are mean ± standard deviation). The correlation coefficients for tubercle deviation, chondromalacia patellae, and trochlear chondromalacia were 0.51 (P < 0.01), 0.44 (P < 0.01), and 0.28 (P < 0.05), respectively. On analysis of variance, tubercle deviation and chondromalacia patellae contributed significantly to prediction of AKP and response to physical therapy. The presence of chondromalacia patellae and a tubercle deviation greater than 14.6 mm is 100% specific and 67% sensitive with a positive predictive value of 100% and negative predictive value of 75% for failure of nonoperative management. Subjects with AKP have more laterally positioned tibial tubercles and are more likely to have patellar chondromalacia. Patients with AKP, chondromalacia patellae, and a tubercle deviation greater than 14.6 mm are unlikely to respond to nonoperative treatment. Knowledge of tibial tubercle lateralization and presence of chondromalacia patellae may assist clinicians in determining patient prognosis and selecting treatment options. (orig.)

  18. Deep sequencing reveals microRNAs predictive of antiangiogenic drug response

    Science.gov (United States)

    García-Donas, Jesús; Beuselinck, Benoit; Inglada-Pérez, Lucía; Graña, Osvaldo; Schöffski, Patrick; Wozniak, Agnieszka; Bechter, Oliver; Apellániz-Ruiz, Maria; Leandro-García, Luis Javier; Esteban, Emilio; Castellano, Daniel E.; González del Alba, Aranzazu; Climent, Miguel Angel; Hernando, Susana; Arranz, José Angel; Morente, Manuel; Pisano, David G.; Robledo, Mercedes

    2016-01-01

    The majority of metastatic renal cell carcinoma (RCC) patients are treated with tyrosine kinase inhibitors (TKI) in first-line treatment; however, a fraction are refractory to these antiangiogenic drugs. MicroRNAs (miRNAs) are regulatory molecules proven to be accurate biomarkers in cancer. Here, we identified miRNAs predictive of progressive disease under TKI treatment through deep sequencing of 74 metastatic clear cell RCC cases uniformly treated with these drugs. Twenty-nine miRNAs were differentially expressed in the tumors of patients who progressed under TKI therapy (P values from 6 × 10–9 to 3 × 10–3). Among 6 miRNAs selected for validation in an independent series, the most relevant associations corresponded to miR–1307-3p, miR–155-5p, and miR–221-3p (P = 4.6 × 10–3, 6.5 × 10–3, and 3.4 × 10–2, respectively). Furthermore, a 2 miRNA–based classifier discriminated individuals with progressive disease upon TKI treatment (AUC = 0.75, 95% CI, 0.64–0.85; P = 1.3 × 10–4) with better predictive value than clinicopathological risk factors commonly used. We also identified miRNAs significantly associated with progression-free survival and overall survival (P = 6.8 × 10–8 and 7.8 × 10–7 for top hits, respectively), and 7 overlapped with early progressive disease. In conclusion, this is the first miRNome comprehensive study, to our knowledge, that demonstrates a predictive value of miRNAs for TKI response and provides a new set of relevant markers that can help rationalize metastatic RCC treatment. PMID:27699216

  19. Prediction of the antiglycation activity of polysaccharides from Benincasa hispida using a response surface methodology.

    Science.gov (United States)

    Jiang, Xiang; Kuang, Fei; Kong, Fansheng; Yan, Chunyan

    2016-10-20

    Benincasa hispida is a popular vegetable in China. Our previous experiments suggested that polysaccharides isolated from B. hispida fruits (PBH) have antiglycation effect and DPPH free radical scavenging activity. Ultrasonic treatments can be used to extract polysaccharides from Benincasa hispida (PBH). The aim of this study was to investigate the correlation between the ultrasonic treatment conditions and the antiglycation activity of PBH. A mathematical model was generated with an artificial neural network (ANN) toolbox from MATLAB to analyze the effects of ultrasonic treatment conditions on antiglycation activity. The response surface plots showed relationships between ultrasonic extraction conditions and bioactivity. The R(2) value of the model was 0.9919, which suggested good fitness of the neural network. The application of genetic algorithms showed that the optimal ultrasonic extraction conditions resulted in the highest antiglycation activity for PBH. These were 150W, 46°C, and 35min. These conditions produced a predicted antiglycation activity of 41.2%; the actual activity was 40.9% under optimal conditions. This is very close to the predicted value. The experimental data indicated that the PBH possessed both antiglycation and antioxidant activities. The maximum actual value of antiglycation was 101.7% that of the positive control, and the PBH inhibited the DPPH free radicals with an EC50 value of 0.98mg/mL. This is 66.2% that of ascorbic acid. These results explained the observations that B. hispida can decrease glucose levels in diabetic patients. The experimental results also showed that the ANN could be used for optimization and prediction. PMID:27474577

  20. Response time variability and response inhibition predict affective problems in adolescent girls, not in boys : the TRAILS study

    NARCIS (Netherlands)

    van Deurzen, Patricia A. M.; Buitelaar, Jan K.; Brunnekreef, J. Agnes; Ormel, Johan; Minderaa, Ruud B.; Hartman, Catharina A.; Huizink, Anja C.; Speckens, Anne E. M.; Oldehinkel, A. J.; Slaats-Willemse, Dorine I. E.

    2012-01-01

    The present study examines the relationship between neurocognitive functioning and affective problems through adolescence, in a cross-sectional and longitudinal perspective. Baseline response speed, response speed variability, response inhibition, attentional flexibility and working memory were asse

  1. Early prediction of outcome and response to alemtuzumab therapy in chronic lymphocytic leukemia.

    Science.gov (United States)

    Rawstron, Andy C; Kennedy, Ben; Moreton, Paul; Dickinson, Anita J; Cullen, Matthew J; Richards, Stephen J; Jack, Andrew S; Hillmen, Peter

    2004-03-15

    Alemtuzumab therapy is effective for some refractory chronic lymphocytic leukemia (CLL), but identifying responders requires at least 8 weeks of therapy. Early identification of nonresponders would minimize toxicity and/or facilitate more effective strategies. The aim of this study was to identify a minimally invasive method for early prediction of response and relapse. Flow cytometric monitoring was performed in 887 blood samples and 201 marrow samples from 43 patients undergoing intravenous alemtuzumab therapy. Although the absolute lymphocytosis was resolved in all patients by week 4, significant depletion of bone marrow tumor only occurred if circulating B-lymphocyte counts were persistently less than 0.001 x 10(9)/L, which was rare in nonresponders. The majority of patients (16/28) who did not benefit from a full course of therapy were identified with 100% positive predictive value using the following algorithm: peripheral B-cell count greater than 0.001 x 10(9)/L at week 2 with less than 1 log depletion of circulating B cells between weeks 2 and 4. Monitoring CLL levels after treatment identified patients at risk of early disease progression and could potentially improve patient management. During alemtuzumab therapy, bone marrow CLL depletion only occurs after abrogation of circulating tumor, requiring close monitoring of circulating B-cell levels. If validated in prospective studies, blood monitoring at 2 and 4 weeks may be used to optimize therapy.

  2. Differential Response of Coral Assemblages to Thermal Stress Underscores the Complexity in Predicting Bleaching Susceptibility.

    Directory of Open Access Journals (Sweden)

    Loke Ming Chou

    Full Text Available Coral bleaching events have been predicted to occur more frequently in the coming decades with global warming. The susceptibility of corals to bleaching during thermal stress episodes is dependent on many factors and an understanding of these underlying drivers is crucial for conservation management. In 2013, a mild bleaching episode ensued in response to elevated sea temperature on the sediment-burdened reefs in Singapore. Surveys of seven sites highlighted variable bleaching susceptibility among coral genera-Pachyseris and Podabacia were the most impacted (31% of colonies of both genera bleached. The most susceptible genera such as Acropora and Pocillopora, which were expected to bleach, did not. Susceptibility varied between less than 6% and more than 11% of the corals bleached, at four and three sites respectively. Analysis of four of the most bleached genera revealed that a statistical model that included a combination of the factors (genus, colony size and site provided a better explanation of the observed bleaching patterns than any single factor alone. This underscored the complexity in predicting the coral susceptibility to future thermal stress events and the importance of monitoring coral bleaching episodes to facilitate more effective management of coral reefs under climate change.

  3. Impediments to predicting site response: Seismic property estimation and modeling simplifications

    Science.gov (United States)

    Thompson, E.M.; Baise, L.G.; Kayen, R.E.; Guzina, B.B.

    2009-01-01

    We compare estimates of the empirical transfer function (ETF) to the plane SH-wave theoretical transfer function (TTF) within a laterally constant medium for invasive and noninvasive estimates of the seismic shear-wave slownesses at 13 Kiban-Kyoshin network stations throughout Japan. The difference between the ETF and either of the TTFs is substantially larger than the difference between the two TTFs computed from different estimates of the seismic properties. We show that the plane SH-wave TTF through a laterally homogeneous medium at vertical incidence inadequately models observed amplifications at most sites for both slowness estimates, obtained via downhole measurements and the spectral analysis of surface waves. Strategies to improve the predictions can be separated into two broad categories: improving the measurement of soil properties and improving the theory that maps the 1D soil profile onto spectral amplification. Using an example site where the 1D plane SH-wave formulation poorly predicts the ETF, we find a more satisfactory fit to the ETF by modeling the full wavefield and incorporating spatially correlated variability of the seismic properties. We conclude that our ability to model the observed site response transfer function is limited largely by the assumptions of the theoretical formulation rather than the uncertainty of the soil property estimates.

  4. Wing Leading Edge RCC Rapid Response Damage Prediction Tool (IMPACT2)

    Science.gov (United States)

    Clark, Robert; Cottter, Paul; Michalopoulos, Constantine

    2013-01-01

    This rapid response computer program predicts Orbiter Wing Leading Edge (WLE) damage caused by ice or foam impact during a Space Shuttle launch (Program "IMPACT2"). The program was developed after the Columbia accident in order to assess quickly WLE damage due to ice, foam, or metal impact (if any) during a Shuttle launch. IMPACT2 simulates an impact event in a few minutes for foam impactors, and in seconds for ice and metal impactors. The damage criterion is derived from results obtained from one sophisticated commercial program, which requires hours to carry out simulations of the same impact events. The program was designed to run much faster than the commercial program with prediction of projectile threshold velocities within 10 to 15% of commercial-program values. The mathematical model involves coupling of Orbiter wing normal modes of vibration to nonlinear or linear springmass models. IMPACT2 solves nonlinear or linear impact problems using classical normal modes of vibration of a target, and nonlinear/ linear time-domain equations for the projectile. Impact loads and stresses developed in the target are computed as functions of time. This model is novel because of its speed of execution. A typical model of foam, or other projectile characterized by material nonlinearities, impacting an RCC panel is executed in minutes instead of hours needed by the commercial programs. Target damage due to impact can be assessed quickly, provided that target vibration modes and allowable stress are known.

  5. Differential Response of Coral Assemblages to Thermal Stress Underscores the Complexity in Predicting Bleaching Susceptibility.

    Science.gov (United States)

    Chou, Loke Ming; Toh, Tai Chong; Toh, Kok Ben; Ng, Chin Soon Lionel; Cabaitan, Patrick; Tun, Karenne; Goh, Eugene; Afiq-Rosli, Lutfi; Taira, Daisuke; Du, Rosa Celia Poquita; Loke, Hai Xin; Khalis, Aizat; Li, Jinghan; Song, Tiancheng

    2016-01-01

    Coral bleaching events have been predicted to occur more frequently in the coming decades with global warming. The susceptibility of corals to bleaching during thermal stress episodes is dependent on many factors and an understanding of these underlying drivers is crucial for conservation management. In 2013, a mild bleaching episode ensued in response to elevated sea temperature on the sediment-burdened reefs in Singapore. Surveys of seven sites highlighted variable bleaching susceptibility among coral genera-Pachyseris and Podabacia were the most impacted (31% of colonies of both genera bleached). The most susceptible genera such as Acropora and Pocillopora, which were expected to bleach, did not. Susceptibility varied between less than 6% and more than 11% of the corals bleached, at four and three sites respectively. Analysis of four of the most bleached genera revealed that a statistical model that included a combination of the factors (genus, colony size and site) provided a better explanation of the observed bleaching patterns than any single factor alone. This underscored the complexity in predicting the coral susceptibility to future thermal stress events and the importance of monitoring coral bleaching episodes to facilitate more effective management of coral reefs under climate change. PMID:27438593

  6. Differential Response of Coral Assemblages to Thermal Stress Underscores the Complexity in Predicting Bleaching Susceptibility

    Science.gov (United States)

    Toh, Kok Ben; Ng, Chin Soon Lionel; Cabaitan, Patrick; Tun, Karenne; Goh, Eugene; Afiq-Rosli, Lutfi; Taira, Daisuke; Du, Rosa Celia Poquita; Loke, Hai Xin; Khalis, Aizat; Li, Jinghan; Song, Tiancheng

    2016-01-01

    Coral bleaching events have been predicted to occur more frequently in the coming decades with global warming. The susceptibility of corals to bleaching during thermal stress episodes is dependent on many factors and an understanding of these underlying drivers is crucial for conservation management. In 2013, a mild bleaching episode ensued in response to elevated sea temperature on the sediment-burdened reefs in Singapore. Surveys of seven sites highlighted variable bleaching susceptibility among coral genera–Pachyseris and Podabacia were the most impacted (31% of colonies of both genera bleached). The most susceptible genera such as Acropora and Pocillopora, which were expected to bleach, did not. Susceptibility varied between less than 6% and more than 11% of the corals bleached, at four and three sites respectively. Analysis of four of the most bleached genera revealed that a statistical model that included a combination of the factors (genus, colony size and site) provided a better explanation of the observed bleaching patterns than any single factor alone. This underscored the complexity in predicting the coral susceptibility to future thermal stress events and the importance of monitoring coral bleaching episodes to facilitate more effective management of coral reefs under climate change. PMID:27438593

  7. Traditional clinical risk factors predict clopidogrel hypo-responsiveness in unselected patients undergoing non-emergent percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Ratcovich, Hanna; Holmvang, Lene; Johansson, Pär Inge;

    2016-01-01

    High and low platelet reactivity, HPR and LPR respectively, to clopidogrel and aspirin have previously been associated with adverse events following percutaneous coronary intervention (PCI). The aim is to test the ability of a previously developed clinical risk-score, the PREDICT score, to identify...... of PREDICT score variables and the incidence of HPR for clopidogrel (HPR (ADP)) (p ... = 0.003); 7-9 points OR 9.84 (95% CI 3.49-27.7, p clopidogrel LPR (LPR (ADP)). On the other hand, there was no clear association between PREDICT score and AA response. The PREDICT...

  8. Response Assessment and Prediction in Esophageal Cancer Patients via F-18 FDG PET/CT Scans

    Science.gov (United States)

    Higgins, Kyle J.

    Purpose: The purpose of this study is to utilize F-18 FDG PET/CT scans to determine an indicator for the response of esophageal cancer patients during radiation therapy. There is a need for such an indicator since local failures are quite common in esophageal cancer patients despite modern treatment techniques. If an indicator is found, a patient's treatment strategy may be altered to possibly improve the outcome. This is investigated with various standard uptake volume (SUV) metrics along with image texture features. The metrics and features showing the most promise and indicating response are used in logistic regression analysis to find an equation for the prediction of response. Materials and Methods: 28 patients underwent F-18 FDG PET/CT scans prior to the start of radiation therapy (RT). A second PET/CT scan was administered following the delivery of ~32 Gray (Gy) of dose. A physician contoured gross tumor volume (GTV) was used to delineate a PET based GTV (GTV-pre-PET) based on a threshold of >40% and >20% of the maximum SUV value in the GTV. Deformable registration was used in VelocityAI software to register the pre-treatment and intra-treatment CT scans so that the GTV-pre-PET contours could be transferred from the pre to intra scans (GTV-intra-PET). The fractional decrease in the maximum, mean, volume to the highest intensity 10%-90%, and combination SUV metrics of the significant previous SUV metrics were compared to post-treatment pathologic response for an indication of response. Next for the >40% threshold, texture features based on a neighborhood gray-tone dimension matrix (NGTDM) were analyzed. The fractional decrease in coarseness, contrast, busyness, complexity, and texture strength were compared to the pathologic response of the patients. From these previous two types of analysis, SUV and texture features, the two most significant results were used in logistic regression analysis to find an equation to predict the probability of a non

  9. Electrophysiological indices of response inhibition in a Go/NoGo task predict self-control in a social context.

    Directory of Open Access Journals (Sweden)

    Kyle Nash

    Full Text Available Recent research demonstrates that response inhibition-a core executive function-may subserve self-regulation and self-control. However, it is unclear whether response inhibition also predicts self-control in the multifaceted, high-level phenomena of social decision-making. Here we examined whether electrophysiological indices of response inhibition would predict self-control in a social context. Electroencephalography was recorded as participants completed a widely used Go/NoGo task (the cued Continuous Performance Test. Participants then interacted with a partner in an economic exchange game that requires self-control. Results demonstrated that greater NoGo-Anteriorization and larger NoGo-P300 peak amplitudes-two established electrophysiological indices of response inhibition-both predicted more self-control in this social game. These findings support continued integration of executive function and self-regulation and help extend prior research into social decision-making processes.

  10. Bronchodilator response following methacholine-induced bronchoconstriction predicts acute asthma exacerbations.

    Science.gov (United States)

    Park, Heung-Woo; Song, Woo-Jung; Chang, Yoon-Suk; Cho, Sang-Heon; Datta, Soma; Weiss, Scott T; Tantisira, Kelan G

    2016-07-01

    Methacholine bronchial provocation test provides the concentration of methacholine causing a 20% decrease in forced expiratory volume in 1 s (FEV1) from baseline (PC20). The dose-response slope (DRS), and other continuous indices of responsiveness (CIR; the percentage decline from the post-diluent baseline FEV1 after the last dose of methacholine), and per cent recovery index (PRI; the percentage increase from the maximally reduced FEV1 after bronchodilator inhalation) are alternative measures. The clinical relevance of these indices in predicting acute asthma exacerbations has not been fully evaluated.In two prospective cohorts of childhood and elderly asthmatics, baseline PC20, DRS, CIR and PRI were measured and evaluated as predictors of acute asthma exacerbations.We found that PRI was significantly related to the presence of asthma exacerbations during the first year of follow-up in both cohorts of childhood (p=0.025) and elderly asthmatics (p=0.003). In addition, PRI showed a significant association with the total number of steroid bursts during 4.3 years of follow-up in the cohort of childhood asthmatics (p=0.04).We demonstrated that PRI, an index of reversibility following methacholine-induced bronchoconstriction, was a good clinical predictor of acute exacerbations of asthma in both childhood and elderly asthmatics. PMID:27076579

  11. Field Measurement-Based System Identification and Dynamic Response Prediction of a Unique MIT Building

    Directory of Open Access Journals (Sweden)

    Young-Jin Cha

    2016-07-01

    Full Text Available Tall buildings are ubiquitous in major cities and house the homes and workplaces of many individuals. However, relatively few studies have been carried out to study the dynamic characteristics of tall buildings based on field measurements. In this paper, the dynamic behavior of the Green Building, a unique 21-story tall structure located on the campus of the Massachusetts Institute of Technology (MIT, Cambridge, MA, USA, was characterized and modeled as a simplified lumped-mass beam model (SLMM, using data from a network of accelerometers. The accelerometer network was used to record structural responses due to ambient vibrations, blast loading, and the October 16th 2012 earthquake near Hollis Center (ME, USA. Spectral and signal coherence analysis of the collected data was used to identify natural frequencies, modes, foundation rocking behavior, and structural asymmetries. A relation between foundation rocking and structural natural frequencies was also found. Natural frequencies and structural acceleration from the field measurements were compared with those predicted by the SLMM which was updated by inverse solving based on advanced multiobjective optimization methods using the measured structural responses and found to have good agreement.

  12. A mouse stromal response to tumor invasion predicts prostate and breast cancer patient survival.

    Directory of Open Access Journals (Sweden)

    Marina Bacac

    Full Text Available Primary and metastatic tumor growth induces host tissue responses that are believed to support tumor progression. Understanding the molecular changes within the tumor microenvironment during tumor progression may therefore be relevant not only for discovering potential therapeutic targets, but also for identifying putative molecular signatures that may improve tumor classification and predict clinical outcome. To selectively address stromal gene expression changes during cancer progression, we performed cDNA microarray analysis of laser-microdissected stromal cells derived from prostate intraepithelial neoplasia (PIN and invasive cancer in a multistage model of prostate carcinogenesis. Human orthologs of genes identified in the stromal reaction to tumor progression in this mouse model were observed to be expressed in several human cancers, and to cluster prostate and breast cancer patients into groups with statistically different clinical outcomes. Univariate Cox analysis showed that overexpression of these genes is associated with shorter survival and recurrence-free periods. Taken together, our observations provide evidence that the expression signature of the stromal response to tumor invasion in a mouse tumor model can be used to probe human cancer, and to provide a powerful prognostic indicator for some of the most frequent human malignancies.

  13. Field Measurement-Based System Identification and Dynamic Response Prediction of a Unique MIT Building

    Science.gov (United States)

    Cha, Young-Jin; Trocha, Peter; Büyüköztürk, Oral

    2016-01-01

    Tall buildings are ubiquitous in major cities and house the homes and workplaces of many individuals. However, relatively few studies have been carried out to study the dynamic characteristics of tall buildings based on field measurements. In this paper, the dynamic behavior of the Green Building, a unique 21-story tall structure located on the campus of the Massachusetts Institute of Technology (MIT, Cambridge, MA, USA), was characterized and modeled as a simplified lumped-mass beam model (SLMM), using data from a network of accelerometers. The accelerometer network was used to record structural responses due to ambient vibrations, blast loading, and the October 16th 2012 earthquake near Hollis Center (ME, USA). Spectral and signal coherence analysis of the collected data was used to identify natural frequencies, modes, foundation rocking behavior, and structural asymmetries. A relation between foundation rocking and structural natural frequencies was also found. Natural frequencies and structural acceleration from the field measurements were compared with those predicted by the SLMM which was updated by inverse solving based on advanced multiobjective optimization methods using the measured structural responses and found to have good agreement. PMID:27376303

  14. Multi-scale simulations predict responses to non-invasive nerve root stimulation

    Science.gov (United States)

    Laakso, Ilkka; Matsumoto, Hideyuki; Hirata, Akimasa; Terao, Yasuo; Hanajima, Ritsuko; Ugawa, Yoshikazu

    2014-10-01

    Objective. Established biophysical neurone models have achieved limited success in reproducing electrophysiological responses to non-invasive stimulation of the human nervous system. This is related to our insufficient knowledge of the induced electric currents inside the human body. Despite the numerous research and clinical applications of non-invasive stimulation, it is still unclear which internal sites are actually affected by it. Approach. We performed multi-scale computer simulations that, by making use of advances in computing power and numerical algorithms, combine a microscopic model of electrical excitation of neurones with a macroscopic electromagnetic model of the realistic whole-body anatomy. Main results. The simulations yield responses consistent with those experimentally recorded following magnetic and electrical motor root stimulation in human subjects, and reproduce the observed amplitudes and latencies for a wide variety of stimulation parameters. Significance. Our findings demonstrate that modern computational techniques can produce detailed predictions about which and where neurones are activated, leading to improved understanding of the physics and basic mechanisms of non-invasive stimulation and enabling potential new applications that make use of improved targeting of stimulation.

  15. Can measurement of apparent diffusion coefficient before treatment predict the response to uterine artery embolization for adenomyosis?

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yaewon; Kim, Man Deuk; Jung, Dae Chul; Lee, Shin Jae; Kim, Gyoungmin; Park, Sung Il; Won, Jong Yun; Lee, Do Yun [Yonsei University College of Medicine, Department of Radiology, Severance Hospital, Seoul (Korea, Republic of)

    2015-05-01

    To determine the usefulness of the apparent diffusion coefficient (ADC) in predicting response to uterine artery embolization (UAE) for symptomatic adenomyosis. A prospective study was performed on 25 patients who underwent diffusion-weighted (DW) magnetic resonance imaging (MRI) before UAE between June 2011 and December 2012. All patients underwent 3-month follow-up MRI after UAE using non-spherical polyvinyl alcohol (PVA) particles ranging from 150 to 500 μm. Quantitative measurement of the ADC was performed for each adenomyosis. Complete response and incomplete response were defined as ≥90 % or <90 %, respectively, of the non-perfusion area with adenomyosis at the follow-up MRI. The ADC values were compared between patients who achieved complete or incomplete response which was assessed according to the MRI findings after UAE. Nineteen patients showed complete response, and six showed incomplete response. The ADC value ranged from 0.842 to 1.346 x 10{sup -3} mm{sup 2}/s (mean 1.075 ± 0.117). The mean ADC was 1.043 ± 0.237 in the complete response group and 1.176 ± 0.429 in the incomplete response group (0.012). Using a threshold of <1.147 x 10{sup -3} mm{sup 2}/s, the sensitivity and specificity of the ADC to predict success after UAE were 83.3 % and 84.2 %. The ADC of adenomyosis may potentially predict a successful response to UAE for adenomyosis. (orig.)

  16. Evaluation of In-111 DTPA-paclitaxel scintigraphy to predict response on murine tumors to paclitaxel

    International Nuclear Information System (INIS)

    Our goal was to determine whether scintigraphy with 111In-DTPA-paclitaxel could predict the response to chemotherapy with paclitaxel. Ovarian carcinoma (OCA 1), mammary carcinoma (MCA-4), fibrosarcoma (FSA) and squamous cell carcinoma (SCC VII) were inoculated into the thighs of female C3Hf/Kam mice. Mice bearing 8 mm tumors were treated with paclitaxel (40 mg/kg). The growth delay, which was defined as the time in days for tumors in the treated groups to grow from 8 to 12 mm in diameter minus the time in days for tumors in the untreated control group to reach the same size, was measured to determine the effect of paclitaxel on the tumors. Sequential scintigraphy in mice bearing 10 to 14 mm tumors was conducted at 5, 30, 60, 120, 240 min and 24 hrs postinjection of 111In-DTPA-paclitaxel (3.7 MBq) or 111In-DTPA as a control tracer. The tumor uptakes (% injection dose/pixel) were determined. The growth delay of OCA 1, MCA-4, FSA and SCC VII tumors was 13.6, 4.0, -0.02 and -0.28 days, respectively. In other words, OCA 1 and MCA-4 were paclitaxel-sensitive tumors, whereas FSA and SCC VII were paclitaxel-resistant tumors. The tumor uptakes at 24 hrs postinjection of In-111 DTPA paclitaxel of OCA 1, MCA-4, FSA and SCC VII were 1.0 x 10-3, 1.6 x 10-3, 2.2 x 10-3 and 9.0 x 10-3% injection dose/pixel, respectively. There was no correlation between the response to chemotherapy with paclitaxel and the tumor uptakes of 111In-DTPA-paclitaxel. Scintigraphy with 111In-DTPA-paclitaxel could not predict the response to paclitaxel chemotherapy. Although there was significant accumulation of the paclitaxel in the tumor cells, additional mechanisms must be operative for the agent to be effective against the neoplasm. 111In-DTPA-paclitaxel activity is apparently different from that of paclitaxel with Cremophor. (author)

  17. Characterization and prediction of subsurface pneumatic response at Yucca Mountain, Nevada

    Science.gov (United States)

    Ahlers, C. Fredrik; Finsterle, Stefan; Bodvarsson, Gudmundur S.

    1999-05-01

    Yucca Mountain, Nevada is being investigated as the proposed site for geologic disposal of the United States' high level nuclear waste. A massive effort to collect data for characterization of the thermo-hydrologic behavior of the unsaturated zone is being conducted at the site. Several boreholes have been instrumented by the United States Geological Survey and the Nye County Nuclear Waste Repository Project Office for passive pneumatic monitoring of the subsurface. One-, two- and three-dimensional numerical models are used to simulate the observed subsurface pressure variations. The data are inverted using these models in order to characterize the unsaturated system and estimate the pneumatic diffusivity of important geologic features. Blind predictions of subsurface response and subsequent comparison to recorded data have built confidence in the models of Yucca Mountain. Inversions show that the pneumatic response of the system is dominated by the Paintbrush non-welded unit (PTn). Faults are shown to be fast pathways for gas flow but affect subsurface response only on a relatively local scale. Estimates of the diffusivity of the tuffs that comprise Yucca Mountain range from a low of 0.008 m 2/s in the non-welded pre-Yucca bedded tuff layer to a high of 4 m 2/s in the densely welded, fractured Topopah Spring tuff. Estimates of diffusivity in fault zones at Yucca Mountain range between 0.03 m 2/s and 1500 m 2/s with the highest being in the Drill Hole Wash fault where it intersects the Topopah Spring tuff.

  18. Baseline Delta Sleep Ratio Predicts Acute Ketamine Mood Response in Major Depressive Disorder

    Science.gov (United States)

    Duncan, Wallace C.; Selter, Jessica; Brutsche, Nancy; Sarasso, Simone; Zarate, Carlos A.

    2012-01-01

    Background Electroencephalographic (EEG) sleep slow wave activity (SWA; EEG power between 0.6–4 Hz) has been proposed as a marker of central synaptic plasticity. Decreased generation of sleep slow waves—a core feature of sleep in depression—indicates underlying plasticity changes in the disease. Various measures of SWA have previously been used to predict antidepressant treatment response. This study examined the relationship between baseline patterns of SWA in the first two NREM episodes and antidepressant response to an acute infusion of the N-methyl-D-aspartate (NMDA) antagonist ketamine. Methods Thirty patients (20M, 10F, 18–65) fulfilling DSM-IV criteria for treatment-resistant major depressive disorder (MDD) who had been drug-free for two weeks received a single open-label infusion of ketamine hydrochloride (.5 mg/kg) over 40 minutes. Depressive symptoms were assessed with the Montgomery-Asberg Depression Rating Scale (MADRS) before and after ketamine infusion. Sleep recordings were obtained the night before the infusion and were visually scored. SWA was computed for individual artifact-free NREM sleep epochs, and averaged for each NREM episode. Delta sleep ratio (DSR) was calculated as SWANREM1 / SWANREM2. Results A significant positive correlation was observed between baseline DSR and reduced MADRS scores from baseline to Day 1 (r=.414, p=.02). Limitations The sample size was relatively small (N=30) and all subjects had treatment-resistant MDD, which may limit the generalizability of the findings. Further studies are needed to replicate and extend this observation to other patient groups. Conclusions DSR may be a useful baseline predictor of ketamine response in individuals with treatment-resistant MDD. PMID:22871531

  19. Managing and predicting low response to standard in vitro fertilization therapy: a review of the options.

    Science.gov (United States)

    Karande, Visjhvanath C

    2003-01-01

    Low responders remain a difficult group of patients to manage in an in vitro fertilization (IVF) program. Such patients have low peak estradiol concentrations (strategies that have been utilized to manage low responders because the definition of a low responder varies widely. Also, very few large prospective randomized trials have compared different protocols. Two stimulation protocols involving varying doses of leuprorelin and high doses of gonadotropins appear to be the most promising. The early gonadotropin-releasing hormone (GnRH) agonist cessation protocol involves routine pituitary desensitization with luteal phase start of leuprorelin 0.5 mg for 10-14 days. With the onset of gonadotropin treatment, there is cessation of leuprorelin. The 'microdose flare' protocol utilizes oral contraceptive priming followed by diluted doses of leuprorelin 50 microg given twice daily. Two days later, stimulation is started by adding high doses of gonadotropins. The microdoses of leuprorelin and the high doses of gonadotropins are then continued until the day of chorionic gonadotropin administration. Patients who do not respond to these protocols or those with severely diminished ovarian reserve are candidates for donor oocytes. The role of GnRH antagonists and the in vitro maturation of oocytes are potentially exciting strategies that are still being investigated. Ultrasound measurements of ovarian volume, baseline antral follicle counts, and Doppler measurement of ovarian stromal blood flow now make it possible to predict low response to IVF therapy. Low response can be expected if the smaller ovary has a volume <3 cm3, or the mean ovarian diameter in the two longest planes is <20 mm. Antral follicle counts of < or = 3 in each ovary are also associated with low response. Data on ovarian stromal blood flow are still unclear, but an ovarian peak systolic velocity of <10 cm/sec is associated with low response. If low response is anticipated based on baseline ultrasound scan, a

  20. Prediction of lip response to orthodontic treatment using a multivariable regression model

    Directory of Open Access Journals (Sweden)

    Amin Shirvani

    2016-01-01

    Conclusion: Within the limitation of this study, multiple regression technique was slightly more accurate than the ratio of mean prediction (Viewbox4.0 software and appears to be useful in the prediction of soft tissue changes. As the variability of the predicted individual outcome seems to be relatively high, caution should be taken in predicting hard and soft tissue positional changes.

  1. A temporal predictive code for voice motor control: Evidence from ERP and behavioral responses to pitch-shifted auditory feedback.

    Science.gov (United States)

    Behroozmand, Roozbeh; Sangtian, Stacey; Korzyukov, Oleg; Larson, Charles R

    2016-04-01

    The predictive coding model suggests that voice motor control is regulated by a process in which the mismatch (error) between feedforward predictions and sensory feedback is detected and used to correct vocal motor behavior. In this study, we investigated how predictions about timing of pitch perturbations in voice auditory feedback would modulate ERP and behavioral responses during vocal production. We designed six counterbalanced blocks in which a +100 cents pitch-shift stimulus perturbed voice auditory feedback during vowel sound vocalizations. In three blocks, there was a fixed delay (500, 750 or 1000 ms) between voice and pitch-shift stimulus onset (predictable), whereas in the other three blocks, stimulus onset delay was randomized between 500, 750 and 1000 ms (unpredictable). We found that subjects produced compensatory (opposing) vocal responses that started at 80 ms after the onset of the unpredictable stimuli. However, for predictable stimuli, subjects initiated vocal responses at 20 ms before and followed the direction of pitch shifts in voice feedback. Analysis of ERPs showed that the amplitudes of the N1 and P2 components were significantly reduced in response to predictable compared with unpredictable stimuli. These findings indicate that predictions about temporal features of sensory feedback can modulate vocal motor behavior. In the context of the predictive coding model, temporally-predictable stimuli are learned and reinforced by the internal feedforward system, and as indexed by the ERP suppression, the sensory feedback contribution is reduced for their processing. These findings provide new insights into the neural mechanisms of vocal production and motor control.

  2. Prediction of response to neoadjuvant chemotherapy in osteosarcoma using dual-phase {sup 18}F-FDG PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Byung Hyun [The Catholic University of Korea, Division of Nuclear Medicine, Department of Radiology, College of Medicine, Seoul (Korea, Republic of); Korea Institute of Radiological and Medical Sciences (KIRAMS), Departments of Nuclear Medicine, Seoul (Korea, Republic of); Kim, Sung Hoon; Chung, Soo Kyo [The Catholic University of Korea, Division of Nuclear Medicine, Department of Radiology, College of Medicine, Seoul (Korea, Republic of); Lim, Sang Moo; Lim, Ilhan [Korea Institute of Radiological and Medical Sciences (KIRAMS), Departments of Nuclear Medicine, Seoul (Korea, Republic of); Kong, Chang-Bae; Song, Won Seok; Cho, Wan Hyeong; Jeon, Dae-Geun; Lee, Soo-Yong [Korea Institute of Radiological and Medical Sciences (KIRAMS), Orthopedic Surgery, Seoul (Korea, Republic of); Koh, Jae-Soo [Korea Institute of Radiological and Medical Sciences (KIRAMS), Pathology, Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2015-07-15

    We evaluated the ability of dual-phase {sup 18}F-FDG PET/CT to predict the histological response after neoadjuvant chemotherapy (NAC) in osteosarcoma. Thirty-one patients with osteosarcoma treated with NAC and surgery were prospectively enrolled. After injection of {sup 18}F-FDG, both early (∝60 min) and delayed (∝150 min) PET were acquired before and after the completion of NAC. SUVmax, early/delayed SUVmax change (RImax), and early/delayed SUVmean change (RImean) of tumour were measured before (SUV1, RImax1, and RImean1) and after NAC (SUV2, RImax2, and RImean2). Then, we calculated the percentage changes between SUV1 and SUV2 (%SUV). Twelve patients (39 %) exhibited good histological response after NAC. SUVmax, RImax, and RImean significantly decreased after NAC. Before NAC, only RImean1 predicted good histological response with the optimal criterion of < 10 %, sensitivity of 92 %, specificity of 57 %, and accuracy of 71 %. After NAC, %SUV, SUV2, and RImax2 predicted histological response. By using combined criterion of %SUV and RImax2 or SUV2 and RImean1 or SUV2 and RImax2, accuracies were 81 %, 77 %, and 77 %, respectively. The histological response after NAC could be predicted by using RImean1 before the initiation of NAC in osteosarcoma. The combined use of SUV and RI values may provide a better prediction. (orig.)

  3. Optimal prediction of human postural response under anterior-posterior platform tilting

    Science.gov (United States)

    Naderi, D.; Miripour Fard, B.; Sadeghi-Mehr, M.

    2013-01-01

    Previous studies have suggested that human beings movements can be related to the problem of cost function minimization. But at the present time it is not clear that which objective function(s) and constraints are used by central nervous system (CNS) to produce optimal reactions under perturbations. Present study has been done experimentally and by numerical simulations to explore the stability constraints which should be used in combination with energy based cost function (weighted minimum torque) to estimate the motor planning criterion is used by CNS for disturbance rejections. The influence of three stability criterions (ZMP, extrapolated center of mass and a vertical force criterion) in combination with minimum torque model on the optimal trajectory formation is investigated. First, the response of 10 male healthy persons to platform oscillation was recorded by motion analysis system and the hip, knee and ankle angular trajectories were derived from recorded data. Second, the dynamic simulation of a four-segment, three actuated degrees of freedom mechanical model of the human body was performed using predictive dynamic method which leads to an optimization problem. The simulated trajectories were then compared to the experimental data. With comparison between experimental results, the weighting coefficients of the objective function were found to achieve best estimation. It was seen that the minimum torque objective function with weighting coefficients gives trajectories that are mostly matched with experimental observation. Moreover, the results showed that between stability criterions, the ZMP predictions are near to experimental results. Although by using vertical force criterion some nearness to experimental results are lost (in comparison with ZMP criterion) but a secured flat-foot posture for the model is obtained which this posture is more applicable than others in humanoid implementations.

  4. Accelerated superfractionated radiotherapy for inflammatory breast carcinoma: complete response predicts outcome and allows for breast conservation

    International Nuclear Information System (INIS)

    Purpose: Chemotherapy and accelerated superfractionated radiotherapy were prospectively applied for inflammatory breast carcinoma with the intent of breast conservation. The efficacy, failure patterns, and patient tolerance utilizing this approach were analyzed. Methods and Materials: Between 1983 and 1996, 52 patients with inflammatory breast carcinoma presented to the Medical College of Virginia Hospitals of VCU and the New England Medical Center. Thirty-eight of these patients were jointly evaluated in multidisciplinary breast clinics and managed according to a defined prospectively applied treatment policy. Patients received induction chemotherapy, accelerated superfractionated radiotherapy, selected use of mastectomy, and concluded with additional chemotherapy. The majority were treated with 1.5 Gy twice daily to field arrangements covering the entire breast and regional lymphatics. An additional 18-21 Gy was then delivered to the breast and clinically involved nodal regions. Total dose to clinically involved areas was 63-66 Gy. Following chemoradiotherapy, patients were evaluated with physical examination, mammogram, and fine needle aspiration x 3. Mastectomy was reserved for those patients with evidence of persistent or progressive disease in the involved breast. All patients received additional chemotherapy. Results: Median age was 51 years. Median follow-up was 23.9 months (6-86) months. The breast preservation rate at the time of last follow-up was 74%. The treated breast or chest wall as the first site of failure occurred in only 13%, and the ultimate local control rate with the selected use of mastectomy was 74%. Ten patients underwent mastectomy, 2 of which had pathologically negative specimens despite a clinically palpable residual mass. Response to chemotherapy was predictive of treatment outcome. Of the 15 patients achieving a complete response, 87% remain locoregionally controlled without the use of mastectomy. Five-year overall survival for

  5. Predicting woodrat (Neotoma) responses to anthropogenic warming from studies of the palaeomidden record

    Science.gov (United States)

    Smith, Felisa A.; Betancourt, Julio L.

    2006-01-01

    Aim The influence of anthropogenic climate change on organisms is an area of great scientific concern. Increasingly there is recognition that abrupt climate transitions have occurred over the late Quaternary; studies of these shifts may yield insights into likely biotic responses to contemporary warming. Here, we review research undertaken over the past decade investigating the response of Neotoma (woodrats) body size and distribution to climate change over the late Quaternary (the last 40,000 years). By integrating information from woodrat palaeomiddens, historical museum specimens and field studies of modern populations, we identify potential evolutionary responses to climate change occurring over a variety of temporal and spatial scales. Specifically, we characterize climatic thresholds in the past that led to local species extirpation and/or range alterations rather than in situ adaptation, and apply them to anticipate potential biotic responses to anthropogenic climate change. Location Middens were collected at about 55 sites scattered across the western United States, ranging from about 34 to 46° N and about 104 to 116° W, respectively. Data for modern populations were drawn from studies conducted in Death Valley, California, Missoula, Montana and the Sevilleta LTER site in central New Mexico. Methods We analysed faecal pellets from midden series collected at numerous cave sites across the western United States. From these we estimated body mass using techniques validated in earlier studies. We compared body size fluctuations at different elevations in different regions and integrated these results with studies investigating temperature–body size tradeoffs in modern animals. We also quantify the rapidity of the size changes over the late Quaternary to estimate the evolutionary capacity of woodrats to deal with predicted rates of anthropogenic climate change over the next century. Results We find remarkable similarities across the geographical range to

  6. pRRophetic: an R package for prediction of clinical chemotherapeutic response from tumor gene expression levels.

    Directory of Open Access Journals (Sweden)

    Paul Geeleher

    Full Text Available We recently described a methodology that reliably predicted chemotherapeutic response in multiple independent clinical trials. The method worked by building statistical models from gene expression and drug sensitivity data in a very large panel of cancer cell lines, then applying these models to gene expression data from primary tumor biopsies. Here, to facilitate the development and adoption of this methodology we have created an R package called pRRophetic. This also extends the previously described pipeline, allowing prediction of clinical drug response for many cancer drugs in a user-friendly R environment. We have developed several other important use cases; as an example, we have shown that prediction of bortezomib sensitivity in multiple myeloma may be improved by training models on a large set of neoplastic hematological cell lines. We have also shown that the package facilitates model development and prediction using several different classes of data.

  7. From field to region yield predictions in response to pedo-climatic variations in Eastern Canada

    Science.gov (United States)

    JÉGO, G.; Pattey, E.; Liu, J.

    2013-12-01

    to improve regional crop modelling. Although several aspects of the coupling between crop models and RS data have been investigated (e.g., inversion of radiative transfer models and neural networks), extensive verification using multiple years and sites is required prior to implementation of the RS assimilation at the regional scale, in order to evaluate the model robustness and consistency in response to climatic variations. STICS performance was evaluated over several years for spring wheat, soybean and corn yield predictions over two small rainfed agricultural region of Eastern Canada exhibiting a high degree of pedodiversity when LAI derived from EO data was assimilated. Averaged yield predictions of the three crops compared well with measurements (10%

  8. From Gaged to Ungaged- Predicting Long-term Environmental Flows, and Ecosystems Responses.

    Science.gov (United States)

    Sengupta, A.; Adams, S. K.; Stein, E. D.; Mazor, R.; Bledsoe, B. P.

    2015-12-01

    Modern management needs, such as water supply, quality, and ecosystem protection place numerous demands on instream flows. Many regions are interested in developing numeric flow criteria as a way of ensuring maintenance of flow patterns that protect biological resources while meeting other demands. Developing flow criteria requires the capacity to generate reliable time series of the daily flow at any stream reach of interest and to relate flow patterns to biological indicators of stream health. Most stream reaches are not gaged, and it is impractical to develop detailed models for all reaches where flow alteration needs to be evaluated. We present a novel mechanistic approach to efficiently predict flows and flow alteration at all ungaged stream locations within a region of interest. We used an "ensemble approach" whereby a series of regionally representative models were developed and calibrated. New sites of interest are assigned to one of the ensemble models based on similarity of catchment properties. For southern California, we selected 43 gaged sites representing the range of geomorphology, and watershed characteristics of streams in the region. For each gaged site, we developed a hydrologic model (HEC-HMS) to predict daily flows for a period representing dry, wet and normal precipitation. The final goal is to relate flow alterations to ecological responses, the models were calibrated to three separate performance metrics that reflect conditions important for instream biological communities- proportion of low flow days, flashiness and Nash Sutcliffe efficiency for overall model performance. We cross-validated the models using a "jack-knife" approach. Models were assigned to novel 840 bioassessment sites based on the results of a Random Forest model that identified catchment properties that most affected the runoff patterns. Daily flow data for existing and "reference conditions" was simulated for a 23-year period for current and reference (undeveloped

  9. Quantitative analysis of nuclear shape in oral squamous cell carcinoma is useful for predicting the chemotherapeutic response.

    Science.gov (United States)

    Ogura, Maki; Yamamoto, Yoichiro; Miyashita, Hitoshi; Kumamoto, Hiroyuki; Fukumoto, Manabu

    2016-06-01

    The number of people afflicted with oral carcinoma in Japan has increased in recent years. Although preoperative neoadjuvant therapy with cisplatin and 5-fluorouracil are performed, chemotherapeutic response varies widely among the patients. With the aim of establishing novel indices to predict the therapeutic response to chemotherapy, we investigated the relationship between morphological features of pre-treatment oral carcinoma nuclei and the chemotherapeutic response using quantifying morphology of cell nuclei in pathological specimen images. We measured 4 morphological features of the nucleus of oral squamous cell carcinoma cases classified by the response to chemotherapy: No Change (NC) group, Partial Response (PR) group and Complete Response (CR) group. Furthermore, we performed immunohistochemical staining for p53 and Ki67 and calculated their positive rates in cancer tissues. Compactness and symmetry of the nucleus were significantly higher and nuclear edge response was significantly lower in cancer cells with lower chemotherapeutic responses compared high chemotherapeutic responders. As for positive rates of p53 and Ki67, there were no significant differences between any of the response groups. Morphological features of cancer cell nuclei in pathological specimens are sensitive predictive factors for the chemotherapeutic response to oral squamous cell carcinoma.

  10. Prediction versus actual response of rocks in an excavation of underground cavern at the Lam Ta Khong pumped storage project

    Energy Technology Data Exchange (ETDEWEB)

    Lertsgoon, P.N. [Electricity Generating Authority of Thailand, Bangkruai Nonthaburi (Thailand)

    2003-07-01

    The Lam Ta Khong Pumped Storage Project represents the first underground power plant in Thailand, and involves the excavation of a large underground cavern. Its dimensions are a 25 span, 175 metres long and 49 metres high. It is excavated in sandstone and siltstone and houses 4 power generator units capable of producing a maximum of 1000 mega watts (MW). The work was completed in 2000. The feasibility study revealed questionable properties of the siltstone which governs the ceiling of the cavern, due to a slacking phenomenon. A comparison between prediction and actual ground responses during excavation was performed for construction safety. PHASES and PHASE2 software were used for the prediction, while the actual rock response was obtained using a monitoring system. The parameters on rock properties from back calculation used in the design were made obvious by the correspondence between the prediction and the actual responses. 2 refs., 1 tab., 5 figs.

  11. Role of p-glycoprotein expression in predicting response to neoadjuvant chemotherapy in breast cancer-a prospective clinical study

    OpenAIRE

    Bhatia Ashima; Bansal Anju; Saxena Sunita; Mittal Mahesh K; Singh Jai; Chintamani,; Kulshreshtha Pranjal

    2005-01-01

    Abstract Background Neoadjuvant chemotherapy (NACT) is an integral part of multi-modality approach in the management of locally advanced breast cancer. It is vital to predict response to chemotherapy in order to tailor the regime for a particular patient. The prediction would help in avoiding the toxicity induced by an ineffective chemotherapeutic regime in a non-responder and would also help in the planning of an alternate regime. Development of resistance to chemotherapeutic agents is a maj...

  12. Prospectively validated predictions of shock and organ failure in individual septic surgical patients: the Systemic Mediator Associated Response Test

    OpenAIRE

    Slotman, Gus J

    2000-01-01

    Introduction: Clinically useful predictions of end-organ function and failure in severe sepsis may be possible through analyzing the interactions among demographics, physiologic parameters, standard laboratory tests, and circulating markers of inflammation. The present study evaluated the ability of such a methodology, the Systemic Mediator Associated Response Test (SMART), to predict the clinical course of septic surgery patients from a database of medical and surgical patients with severe s...

  13. In Silico Analysis of Microarray-Based Gene Expression Profiles Predicts Tumor Cell Response to Withanolides

    Directory of Open Access Journals (Sweden)

    Thomas Efferth

    2012-05-01

    Full Text Available Withania somnifera (L. Dunal (Indian ginseng, winter cherry, Solanaceae is widely used in traditional medicine. Roots are either chewed or used to prepare beverages (aqueous decocts. The major secondary metabolites of Withania somnifera are the withanolides, which are C-28-steroidal lactone triterpenoids. Withania somnifera extracts exert chemopreventive and anticancer activities in vitro and in vivo. The aims of the present in silico study were, firstly, to investigate whether tumor cells develop cross-resistance between standard anticancer drugs and withanolides and, secondly, to elucidate the molecular determinants of sensitivity and resistance of tumor cells towards withanolides. Using IC50 concentrations of eight different withanolides (withaferin A, withaferin A diacetate, 3-azerininylwithaferin A, withafastuosin D diacetate, 4-B-hydroxy-withanolide E, isowithanololide E, withafastuosin E, and withaperuvin and 19 established anticancer drugs, we analyzed the cross-resistance profile of 60 tumor cell lines. The cell lines revealed cross-resistance between the eight withanolides. Consistent cross-resistance between withanolides and nitrosoureas (carmustin, lomustin, and semimustin was also observed. Then, we performed transcriptomic microarray-based COMPARE and hierarchical cluster analyses of mRNA expression to identify mRNA expression profiles predicting sensitivity or resistance towards withanolides. Genes from diverse functional groups were significantly associated with response of tumor cells to withaferin A diacetate, e.g. genes functioning in DNA damage and repair, stress response, cell growth regulation, extracellular matrix components, cell adhesion and cell migration, constituents of the ribosome, cytoskeletal organization and regulation, signal transduction, transcription factors, and others.

  14. NUMERICAL PREDICTION OF PROPELLER EXCITED ACOUSTIC RESPONSE OF SUBMARINE STRUCTURE BASED ON CFD, FEM AND BEM

    Institute of Scientific and Technical Information of China (English)

    WEI Ying-san; WANG Yong-sheng; CHANG Shu-ping; FU Jian

    2012-01-01

    A mesh-less Refined Integral Algorithm (RIA) of Boundary Element Method (BEM) is proposed to accurately solve the Helmholtz Integral Equation (HIE).The convergence behavior and the practicability of the method are validated.Computational Fluid Dynamics (CFD),Finite Element Method (FEM) and RIA are used to predict the propeller excited underwater noise of the submarine hull structure.Firstly the propeller and submarine's flows are independently validated,then the self propulsion of the “submarine+propeller” system is simulated via CFD and the balanced point of the system is determined as well as the self propulsion factors.Secondly,the transient response of the “submarine + propeller” system is analyzed at the balanced point,and the propeller thrust and torque excitations are calculated.Thirdly the thrust and the torque excitations of the propeller are loaded on the submarine,respectively,to calculate the acoustic response,and the sound pover and the main peak frequencies are obtained.Results show that:(1) the thrust mainly excites the submarine axial mode and the high frequency area appears at the two conical-type ends,while the torque mainly excites the circumferential mode and the high frequency area appears at the broadside of the cylindrical section,but with rather smaller sound power and radiation efficiency than the former,(2) the main sound source appears at BPF and 2BPF and comes from the harmonic propeller excitations.So,the main attention should be paid on the thrust excitation control for the sound reduction of the propeller excited submarine structure.

  15. Predictive imaging of chemotherapeutic response in a transgenic mouse model of pancreatic cancer.

    Science.gov (United States)

    Wang, Ping; Yoo, Byunghee; Sherman, Sarah; Mukherjee, Pinku; Ross, Alana; Pantazopoulos, Pamela; Petkova, Victoria; Farrar, Christian; Medarova, Zdravka; Moore, Anna

    2016-08-01

    The underglycosylated mucin 1 tumor antigen (uMUC1) is a biomarker that forecasts the progression of adenocarcinomas. In this study, we evaluated the utility of a dual-modality molecular imaging approach based on targeting uMUC1 for monitoring chemotherapeutic response in a transgenic murine model of pancreatic cancer (KCM triple transgenic mice). An uMUC1-specific contrast agent (MN-EPPT) was synthesized for use with magnetic resonance imaging (MRI) and fluorescence optical imaging. It consisted of dextran-coated iron oxide nanoparticles conjugated to the near infrared fluorescent dye Cy5.5 and to a uMUC1-specific peptide (EPPT). KCM triple transgenic mice were given gemcitabine as chemotherapy while control animals received saline injections following the same schedule. Changes in uMUC1 levels following chemotherapy were monitored using T2-weighted MRI and optical imaging before and 24 hr after injection of the MN-EPPT. uMUC1 expression in tumors from both groups was evaluated by histology and qRT-PCR. We observed that the average delta-T2 in the gemcitabine-treated group was significantly reduced compared to the control group indicating lower accumulation of MN-EPPT, and correspondingly, a lower level of uMUC1 expression. In vivo optical imaging confirmed the MRI findings. Fluorescence microscopy of pancreatic tumor sections showed a lower level of uMUC1 expression in the gemcitabine-treated group compared to the control, which was confirmed by qRT-PCR. Our data proved that changes in uMUC1 expression after gemcitabine chemotherapy could be evaluated using MN-EPPT-enhanced in vivo MR and optical imaging. These results suggest that the uMUC1-targeted imaging approach could provide a useful tool for the predictive assessment of therapeutic response. PMID:26996122

  16. Oscillatory shear response of dilute ferrofluids: predictions from rotational Brownian dynamics simulations and ferrohydrodynamics modeling.

    Science.gov (United States)

    Soto-Aquino, D; Rosso, D; Rinaldi, C

    2011-11-01

    Ferrofluids are colloidal suspensions of magnetic nanoparticles that exhibit normal liquid behavior in the absence of magnetic fields but respond to imposed magnetic fields by changing their viscosity without loss of fluidity. The response of ferrofluids to constant shear and magnetic fields has received a lot of attention, but the response of ferrofluids to oscillatory shear remains largely unexplored. In the present work we used rotational Brownian dynamics to study the dynamic properties of ferrofluids with thermally blocked nanoparticles under oscillatory shear and constant magnetic fields. Comparisons between simulations and modeling using the ferrohydrodynamics equations were also made. Simulation results show that, for small rotational Péclet number, the in-phase and out-of-phase components of the complex viscosity depend on the magnitude of the magnetic field and frequency of the shear, following a Maxwell-like model with field-dependent viscosity and characteristic time equal to the field-dependent transverse magnetic relaxation time of the nanoparticles. Comparison between simulations and the numerical solution of the ferrohydrodynamic equations shows that the oscillatory rotational magnetoviscosity for an oscillating shear field obtained using the kinetic magnetization relaxation equation quantitatively agrees with simulations for a wide range of Péclet number and Langevin parameter but has quantitative deviations from the simulations at high values of the Langevin parameter. These predictions indicate an apparent elastic character to the rheology of these suspensions, even though we are considering the infinitely dilute limit in which there are negligible particle-particle interactions and, as such, chains do not form. Additionally, an asymptotic analytical solution of the ferrohydrodynamics equations, valid for Peferrofluids under conditions of small shear rates. At higher shear rates the Cox-Merz rule ceases to apply. PMID:22181497

  17. The Factors That May Predict Response to Rituximab Therapy in Recurrent Focal Segmental Glomerulosclerosis: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Carlos E. Araya

    2011-01-01

    Full Text Available Recurrence of FSGS occurs in 30–40% of allografts. Therapies for recurrence are not well established. We retrieved all published reports depicting kidney transplant recipients with focal segmental glomerulosclerosis (FSGS recurrence, treated with rituximab, to determine factors associated with treatment response. We found 18 reports of 39 transplant recipients who received rituximab. By univariate analysis for two outcomes (no response versus any response, fewer rituximab infusions and normal serum albumin at recurrence were associated with treatment response. For 3 outcomes (no response, partial and complete remission, male gender, fewer rituximab infusions, shorter time to rituximab treatment, and normal serum albumin were associated with remission. Multivariate analysis for both models revealed that normal serum albumin at FSGS recurrence and lower age at transplant were associated with response. Rituximab for recurrence of FSGS may be beneficial for only some patients. A younger age at transplant and normal serum albumin level at recurrence diagnosis may predict response.

  18. Variations in the pre-ejection period induced by ventricular extra systoles may be feasible to predict fluid responsiveness.

    Science.gov (United States)

    Vistisen, Simon Tilma; Andersen, Kristian Kjær; Frederiksen, Christian Alcaraz; Kirkegaard, Hans

    2014-08-01

    Monitoring that can predict fluid responsiveness is an unsettled matter for spontaneously breathing patients. Based on the convincing results with dynamic monitoring based on preload variations induced by mechanical ventilation, we hypothesised that the extra systolic post-ectopic beat could constitute a similar intermittent preload shift inducing a brief variation in blood pressure and that the magnitude of this variation could predict the hemodynamic response to volume expansion in sedated pigs. Ten pigs were sedated and hemodynamically monitored and four intravascular volume shifts were made: blood depletion (25% of estimated blood volume; 660 ml), retransfusion (of 500 ml depleted blood), and two sequential volume expansions (500 ml colloid each). Between volume shifts, supraventricular and ventricular extra systoles were induced by a pacemaker. Hemodynamic variables such as pulse pressure (PP) and pre-ejection period (PEP) were determined for each heart beat and the hemodynamic changes in the post-ectopic beats compared to sinus beats was extracted (e.g. ∆PP and ∆PEP) and used to predict fluid responsiveness of subsequent volume expansions which was determined by receiver operating characteristic (ROC) curves. Ventricular extra systoles were generally useful for fluid responsiveness prediction (ROC areas >0.65). ∆PEP variables best predicted fluid responsiveness: ∆PEP derived from arterial pressure curve and ECG had ROC area of 0.84 and sensitivity of 0.77 and specificity of 0.71; ∆PEP derived from plethysmographic curve and ECG had ROC area of 0.79 and sensitivity of 0.71 and specificity of 0.70. However, ∆PP was not a useful variable in this study (ROC area <0.65). Hemodynamic analysis of post ectopic beats may be a feasible method for fluid responsiveness prediction. PMID:24203263

  19. Parametric response mapping of dynamic CT for predicting intrahepatic recurrence of hepatocellular carcinoma after conventional transcatheter arterial chemoembolization

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seung Joon; Kim, Hyung Sik [Gachon University Gil Hospital, Department of Radiology, Incheon (Korea, Republic of); Kim, Jonghoon [Sungkyunkwan University, Department of Electronic Electrical and Computer Engineering, Suwon (Korea, Republic of); Seo, Jongbum [Yonsei University, Department of Biomedical Engineering, Wonju (Korea, Republic of); Lee, Jong-min [Hanyang University, Department of Biomedical Engineering, Seoul (Korea, Republic of); Park, Hyunjin [Sungkyunwkan University, School of Electronic and Electrical Engineering, Suwon (Korea, Republic of)

    2016-01-15

    The aim of our study was to determine the diagnostic value of a novel image analysis method called parametric response mapping (PRM) for prediction of intrahepatic recurrence of hepatocellular carcinoma (HCC) treated with conventional transcatheter arterial chemoembolization (TACE). This retrospective study was approved by the IRB. We recruited 55 HCC patients who achieved complete remission (CR) after TACE and received longitudinal multiphasic liver computed tomography (CT). The patients fell into two groups: the recurrent tumour group (n = 29) and the non-recurrent tumour group (n = 26). We applied the PRM analysis to see if this technique could distinguish between the two groups. The results of the PRM analysis were incorporated into a prediction algorithm. We retrospectively removed data from the last time point and attempted to predict the response to therapy of the removed data. The PRM analysis was able to distinguish between the non-recurrent and recurrent groups successfully. The prediction algorithm detected response to therapy with an area under the curve (AUC) of 0.76, while the manual approach had AUC 0.64. Adopting PRM analysis can potentially distinguish between recurrent and non-recurrent HCCs and allow for prediction of response to therapy after TACE. (orig.)

  20. From Boundary Layer Turbulence to Hydrologic Response: Recent Results on Scaling, Nonlinearity, and Predictability and Their Implications

    Science.gov (United States)

    Foufoula-Georgiou, E.

    2002-12-01

    Deepening our understanding of the space-time variability of atmospheric/hydrologic processes and their interactions over a range of scales has important implications for improving model parameterizations and increasing the accuracy of predictive models. At the same time, the inherent nonlinear and chaotic character of some of these processes imposes limits on their predictability, and therefore provides upper bounds on the expected prediction accuracy from numerical models. This paper will address questions of scaling, nonlinearity and predictability in processes active at two major interfaces of the hydrologic system: the land-atmosphere interface, and the land-water interface. Specifically, recent findings and their practical implications will be presented on: (a) multiscale interactions in turbulent boundary layers and implications for boundary condition formulations; (b) predictability assessment of turbulent velocities in a boundary layer as a function of scale; and (c) nonlinear dynamics of basin hydrologic response as a function of spatio-temporally varying forcing and basin geomorphological organization.

  1. New Method for Predicting the Motion Responses of A Flexible Joint Multi-Body Floating System to Irregular Waves

    Institute of Scientific and Technical Information of China (English)

    陈徐均; 崔维成; 沈庆; 孙芦忠

    2001-01-01

    A new hybrid method of frequency domain and time domain is developed in this paper to predict the motion responses of a flexibly joint multi- body floating system to irregular waves. The main idea of the method is that the three-dimensional frequency method is used to obtain the hydrodynamic coefficients and the response equations are solved in time domain step by step. All the forces can be obtained at the same time. The motions and nonlinear mooring forces of a box type six-body floating system are predicted. A comparison of the theoretical method-based solutions with experimental results has shown good agreement.

  2. Stroke volume variation does not predict fluid responsiveness in patients with septic shock on pressure support ventilation

    DEFF Research Database (Denmark)

    Perner, A; Faber, T

    2006-01-01

    Stroke volume variation (SVV)--as measured by the pulse contour cardiac output (PiCCO) system--predicts the cardiac output response to a fluid challenge in patients on controlled ventilation. Whether this applies to patients on pressure support ventilation is unknown.......Stroke volume variation (SVV)--as measured by the pulse contour cardiac output (PiCCO) system--predicts the cardiac output response to a fluid challenge in patients on controlled ventilation. Whether this applies to patients on pressure support ventilation is unknown....

  3. Artificial Neural Network and Response Surface Methodology Modeling in Ionic Conductivity Predictions of Phthaloylchitosan-Based Gel Polymer Electrolyte

    Directory of Open Access Journals (Sweden)

    Ahmad Danial Azzahari

    2016-01-01

    Full Text Available A gel polymer electrolyte system based on phthaloylchitosan was prepared. The effects of process variables, such as lithium iodide, caesium iodide, and 1-butyl-3-methylimidazolium iodide were investigated using a distance-based ternary mixture experimental design. A comparative approach was made between response surface methodology (RSM and artificial neural network (ANN to predict the ionic conductivity. The predictive capabilities of the two methodologies were compared in terms of coefficient of determination R2 based on the validation data set. It was shown that the developed ANN model had better predictive outcome as compared to the RSM model.

  4. Predicting the Probability of Abnormal Stimulated Growth Hormone Response in Children After Radiotherapy for Brain Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hua Chiaho, E-mail: Chia-Ho.Hua@stjude.org [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Wu Shengjie [Department of Biostatistics, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Chemaitilly, Wassim [Division of Endocrinology, Department of Pediatric Medicine, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Lukose, Renin C.; Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2012-11-15

    Purpose: To develop a mathematical model utilizing more readily available measures than stimulation tests that identifies brain tumor survivors with high likelihood of abnormal growth hormone secretion after radiotherapy (RT), to avoid late recognition and a consequent delay in growth hormone replacement therapy. Methods and Materials: We analyzed 191 prospectively collected post-RT evaluations of peak growth hormone level (arginine tolerance/levodopa stimulation test), serum insulin-like growth factor 1 (IGF-1), IGF-binding protein 3, height, weight, growth velocity, and body mass index in 106 children and adolescents treated for ependymoma (n = 72), low-grade glioma (n = 28) or craniopharyngioma (n = 6), who had normal growth hormone levels before RT. Normal level in this study was defined as the peak growth hormone response to the stimulation test {>=}7 ng/mL. Results: Independent predictor variables identified by multivariate logistic regression with high statistical significance (p < 0.0001) included IGF-1 z score, weight z score, and hypothalamic dose. The developed predictive model demonstrated a strong discriminatory power with an area under the receiver operating characteristic curve of 0.883. At a potential cutoff point of probability of 0.3 the sensitivity was 80% and specificity 78%. Conclusions: Without unpleasant and expensive frequent stimulation tests, our model provides a quantitative approach to closely follow the growth hormone secretory capacity of brain tumor survivors. It allows identification of high-risk children for subsequent confirmatory tests and in-depth workup for diagnosis of growth hormone deficiency.

  5. Neuromagnetic oscillations predict evoked-response latency delays and core language deficits in autism spectrum disorders.

    Science.gov (United States)

    Edgar, J Christopher; Khan, Sarah Y; Blaskey, Lisa; Chow, Vivian Y; Rey, Michael; Gaetz, William; Cannon, Katelyn M; Monroe, Justin F; Cornew, Lauren; Qasmieh, Saba; Liu, Song; Welsh, John P; Levy, Susan E; Roberts, Timothy P L

    2015-02-01

    Previous studies have observed evoked response latency as well as gamma band superior temporal gyrus (STG) auditory abnormalities in individuals with autism spectrum disorders (ASD). A limitation of these studies is that associations between these two abnormalities, as well as the full extent of oscillatory phenomena in ASD in terms of frequency and time, have not been examined. Subjects were presented pure tones at 200, 300, 500, and 1,000 Hz while magnetoencephalography assessed activity in STG auditory areas in a sample of 105 children with ASD and 36 typically developing controls (TD). Findings revealed a profile such that auditory STG processes in ASD were characterized by pre-stimulus abnormalities across multiple frequencies, then early high-frequency abnormalities followed by low-frequency abnormalities. Increased pre-stimulus activity was a 'core' abnormality, with pre-stimulus activity predicting post-stimulus neural abnormalities, group membership, and clinical symptoms (CELF-4 Core Language Index). Deficits in synaptic integration in the auditory cortex are associated with oscillatory abnormalities in ASD as well as patient symptoms. Increased pre-stimulus activity in ASD likely demonstrates a fundamental signal-to-noise deficit in individuals with ASD, with elevations in oscillatory activity suggesting an inability to maintain an appropriate 'neural tone' and an inability to rapidly return to a resting state prior to the next stimulus. PMID:23963591

  6. Vibration Response Prediction of Plate with Particle Dampers Using Cosimulation Method

    Directory of Open Access Journals (Sweden)

    Dongqiang Wang

    2015-01-01

    Full Text Available The particle damping technology is a passive vibration control technique. The particle dampers (PDs as one of the passive damping devices has found wide use in the field of aeronautical engineering, mechanical engineering, and civil engineering because it has several advantages compared with the forms of viscous damping, for example, structure simplicity, low cost, robust properties, and being effective over a wide range of frequencies. In this paper, a novelty simulation method based on multiphase flow theory (MFT is developed to evaluate the particle damping characteristics using FEM combining DEM with COMSOL Multiphysics. First, the effects of the collisions and friction between the particles are interpreted as an equivalent nonlinear viscous damping based on MFT of gas particle. Next, the contribution of PDs is estimated as equivalent spring-damper system. Then a cantilever rectangular plate treated with PDs is introduced in a finite element model of structure system. Finally frequency response functions (FRFs of the plate without and with particle dampers are predicted to study characteristics of the particle damping plates under forced vibration. Meanwhile, an experimental verification is performed. Simulation results are in good agreement with experiment date. It is concluded that the simulation method in this paper is valid.

  7. Analytical capability for predicting structural response of NPP concrete containments to severe loads

    International Nuclear Information System (INIS)

    A survey has been conducted on the state-of-the-art of analytical techniques for predicting the structural response of concrete containment buildings under severe accident conditions. The validity of inelastic analysis is often limited by the inadequacy of the material models adopted. This is specially true in the case of materials which undergo localization phenomena in the course of the deformation process. Because of this, the Joint Research Centre at Ispra has given a high priority to the review of existing constitutive models for concrete. Such models must be able to describe concrete behaviour with and without steel reinforcement across the complete stress range, from initial elastic behaviour to and beyond the point of failure. For reinforced and prestressed concrete, segregated models (where concrete and steel are independently simulated) are preferred. A review of existing constitutive models for mass concrete has been conducted. The review focused on necessary features for describing the near-peak and post-peak stages of deformation. Special attention was dedicated to the localization of strains in tension and the post-peak softening behaviour. Existing models for representing the concrete steel bond were also reviewed. These models are still relatively simplistic and incorporate seldom a number of effects of considerable importance: sustained, dynamic and cyclic loading, environmental effects, etc. Finally, the computational procedures currently available for modelling problems involving the ultimate capacity of concrete containments have also been reviewed. This includes methodologies for modelling amongst other mass concrete, cracking procedures, bond behaviour, in existing computer codes

  8. Modeling light adaptation in circadian clock: prediction of the response that stabilizes entrainment.

    Science.gov (United States)

    Tsumoto, Kunichika; Kurosawa, Gen; Yoshinaga, Tetsuya; Aihara, Kazuyuki

    2011-01-01

    Periods of biological clocks are close to but often different from the rotation period of the earth. Thus, the clocks of organisms must be adjusted to synchronize with day-night cycles. The primary signal that adjusts the clocks is light. In Neurospora, light transiently up-regulates the expression of specific clock genes. This molecular response to light is called light adaptation. Does light adaptation occur in other organisms? Using published experimental data, we first estimated the time course of the up-regulation rate of gene expression by light. Intriguingly, the estimated up-regulation rate was transient during light period in mice as well as Neurospora. Next, we constructed a computational model to consider how light adaptation had an effect on the entrainment of circadian oscillation to 24-h light-dark cycles. We found that cellular oscillations are more likely to be destabilized without light adaption especially when light intensity is very high. From the present results, we predict that the instability of circadian oscillations under 24-h light-dark cycles can be experimentally observed if light adaptation is altered. We conclude that the functional consequence of light adaptation is to increase the adjustability to 24-h light-dark cycles and then adapt to fluctuating environments in nature.

  9. Prolactin stress response does not predict brood desertion in a polyandrous shorebird.

    Science.gov (United States)

    Kosztolányi, András; Küpper, Clemens; Chastel, Olivier; Parenteau, Charline; Yılmaz, K Tuluhan; Miklósi, Adám; Székely, Tamás; Lendvai, Adám Z

    2012-05-01

    One of the fundamental principles of the life-history theory is that parents need to balance their resources between current and future offspring. Deserting the dependent young is a radical life-history decision that saves resources for future reproduction but that may cause the current brood to fail. Despite the importance of desertion for reproductive success, and thus fitness, the neuroendocrine mechanisms of brood desertion are largely unknown. We investigated two candidate hormones that may influence brood desertion in the Kentish plover Charadrius alexandrinus: prolactin ('parental hormone') and corticosterone ('stress hormone'). Kentish plovers exhibit an unusually diverse mating and parental care system: brood desertion occurs naturally since either parent (the male or the female) may desert the brood after the chicks hatch and mate with a new partner shortly after. We measured the hormone levels of parents at hatching using the standard capture and restraint protocol. We subsequently followed the broods to determine whether a parent deserted the chicks. We found no evidence that either baseline or stress-induced prolactin levels of male or female parents predicted brood desertion. Although stress-induced corticosterone levels were generally higher in females compared with males, individual corticosterone levels did not explain the probability of brood desertion. We suggest that, in this species, low prolactin levels do not trigger brood desertion. In general, we propose that the prolactin stress response does not reflect overall parental investment in a species where different parts of the breeding cycle are characterized by contrasting individual investment strategies. PMID:22504343

  10. Role of genetics in prediction of disease course and response to therapy

    Science.gov (United States)

    Vermeire, Severine; Van Assche, Gert; Rutgeerts, Paul

    2010-01-01

    The clinical course of Crohn’s disease and ulcerative colitis is highly variable between patients, and this has therapeutic implications. A number of clinical features have been identified, which predict a mild or more severe outcome. However, several of these are subjective and/or not persistent over time. With the progress in genetics research in inflammatory bowel disease (IBD), genetic markers are increasingly being proposed to improve stratification of patients. Genetics have the major advantage of being stable over time and not prone to subjective interpretation. Nevertheless, none of the genetic variants associated with particular outcomes have shown sufficient sensitivity or specificity to have been implemented in daily management. Along the same line of thinking, pharmacogenetics or the study of association between variability in drug response and genetic variation has also received more attention as part of the endeavor for personalized medicine. The ultimate goal in this area of medicine is to adapt medication to a patient’s specific genetic background and therefore improve on efficacy and safety rates. Although pharmacogenetic studies have been performed for all classes of drugs applied in IBD, few have generated consistent findings or have been replicated. The only genetic test approved for clinical practice is thiopurine S-methyltransferase testing prior to starting treatment with thiopurine analogues. The other reported associations have suffered from lack of confirmation or still need replication efforts. Nevertheless, the importance and necessity of pharmacogenetic studies will increase further as more therapeutic classes are being developed. PMID:20518082

  11. Characteristics of MRI features in Alzheimer's disease patients predicting response to donepezil treatment

    International Nuclear Information System (INIS)

    We attempted to investigate whether morphological features as shown on magnetic resonance imaging (MRI) predict response to donepezil treatment in patients with Alzheimer's disease (AD). Sixty-three patients with AD were divided into responders (n=16) and non-responders (n=47) based on the changes in the mini mental state examinations (MMSE) score between baseline and endpoint. Atrophy of the substantia innominata was more pronounced in responders than non-responders. Although no significant difference in the medial temporal lobe atrophy between responders and non-responders was found, magnetization transfer ratios (MTRs) of the hippocampus and parahippocampus, indicators of structural damage, in the non-responder group were significantly reduced compared to those in the responder group. There were no significant differences in the severity of white matter lesions between the two groups. Logistic regression analysis revealed that the overall discrimination rate was 81%, with 85% of non-responders and 69% of responders, through measurement of the thickness of the substantia innominata and MTR of the hippocampus and parahippocampus. These results suggest that AD patients who show more severe cholinergic dysfunction and less severe structural damage of the hippocampus and parahippocampus as shown on MRI are likely to respond to donepezil treatment. (author)

  12. The predicted circulation response to global warming and implications for regional hydroclimate.

    Science.gov (United States)

    Simpson, Isla; Seager, Richard; Ting, Mingfang; Shaw, Tiffany

    2016-04-01

    A critical aspect of human-induced climate change is how it will affect regional hydroclimate around the world. To leading order, the increased ability of the atmosphere to hold moisture as it warms, intensifies moisture transports, making sub-tropical dry regions drier and mid- to high latitude wet regions wetter. But regional changes in hydroclimate will also depend on how the atmospheric circulation responds to warming. Here, the predictions of the future of the mid-latitude circulation by the current generation of global climate models will be discussed, with a particular focus on circulation changes that impact on regional hydroclimate. In the Northern Hemisphere winter, stationary wave changes are a leading order effect and impact on both North American and European hydroclimate. However, in certain regions, models exhibit considerable diversity in this response, motivating the need for improved understanding of the mechanisms involved and the reasons behind such a model spread. This is particularly true in the Pacific-North American sector during winter and so the mechanisms involved in circulation changes in this region and the reason for the inter-model spread will be discussed in detail.

  13. Uncertainties in modeling and scaling in the prediction of fuel stored energy and thermal response

    International Nuclear Information System (INIS)

    The steady-state temperature distribution and the stored energy in nuclear fuel elements are computed by analytical methods and used to rank, in the order of importance, the effects on stored energy from statistical uncertainties in modeling parameters, in boundary and in operating conditions. An integral technique is used to calculate the transient fuel temperature and to estimate the uncertainties in predicting the fuel thermal response and the peak clad temperature during a large-break loss of coolant accident. The uncertainty analysis presented here is an important part of evaluating the applicability, the uncertainties and the scaling capabilities of computer codes for nuclear reactor safety analyses. The methods employed in this analysis merit general attention because of their simplicity. It is shown that the blowdown peak is dominated by fuel stored energy alone or, equivalently, by linear heating rate. Gap conductance, peaking factors and fuel thermal conductivity are the three most important fuel modeling parameters affecting peak clad temperature uncertainty. 26 refs., 10 figs., 6 tabs

  14. Neuroimaging biomarkers to predict treatment response in schizophrenia: the end of 30 years of solitude?

    Science.gov (United States)

    Dazzan, Paola

    2014-12-01

    Studies that have used structural magnetic resonance imaging (MRI) suggest that individuals with psychoses have brain alterations, particularly in frontal and temporal cortices, and in the white matter tracts that connect them. Furthermore, these studies suggest that brain alterations may be particularly prominent, already at illness onset, in those individuals more likely to have poorer outcomes (eg, higher number of hospital admissions, and poorer symptom remission, level of functioning, and response to the first treatment with antipsychotic drugs). The fact that, even when present, these brain alterations are subtle and distributed in nature, has limited, until now, the utility of MRI in the clinical management of these disorders. More recently, MRI approaches, such as machine learning, have suggested that these neuroanatomical biomarkers can be used for direct clinical benefits. For example, using support vector machine, MRI data obtained at illness onset have been used to predict, with significant accuracy, whether a specific individual is likely to experience a remission of symptoms later on in the course of the illness. Taken together, this evidence suggests that validated, strong neuroanatomical markers could be used not only to inform tailored intervention strategies in a single individual, but also to allow patient stratification in clinical trials for new treatments.

  15. Protein-DNA binding dynamics predict transcriptional response to nutrients in archaea.

    Science.gov (United States)

    Todor, Horia; Sharma, Kriti; Pittman, Adrianne M C; Schmid, Amy K

    2013-10-01

    Organisms across all three domains of life use gene regulatory networks (GRNs) to integrate varied stimuli into coherent transcriptional responses to environmental pressures. However, inferring GRN topology and regulatory causality remains a central challenge in systems biology. Previous work characterized TrmB as a global metabolic transcription factor in archaeal extremophiles. However, it remains unclear how TrmB dynamically regulates its ∼100 metabolic enzyme-coding gene targets. Using a dynamic perturbation approach, we elucidate the topology of the TrmB metabolic GRN in the model archaeon Halobacterium salinarum. Clustering of dynamic gene expression patterns reveals that TrmB functions alone to regulate central metabolic enzyme-coding genes but cooperates with various regulators to control peripheral metabolic pathways. Using a dynamical model, we predict gene expression patterns for some TrmB-dependent promoters and infer secondary regulators for others. Our data suggest feed-forward gene regulatory topology for cobalamin biosynthesis. In contrast, purine biosynthesis appears to require TrmB-independent regulators. We conclude that TrmB is an important component for mediating metabolic modularity, integrating nutrient status and regulating gene expression dynamics alone and in concert with secondary regulators.

  16. Protein–DNA binding dynamics predict transcriptional response to nutrients in archaea

    Science.gov (United States)

    Todor, Horia; Sharma, Kriti; Pittman, Adrianne M. C.; Schmid, Amy K.

    2013-01-01

    Organisms across all three domains of life use gene regulatory networks (GRNs) to integrate varied stimuli into coherent transcriptional responses to environmental pressures. However, inferring GRN topology and regulatory causality remains a central challenge in systems biology. Previous work characterized TrmB as a global metabolic transcription factor in archaeal extremophiles. However, it remains unclear how TrmB dynamically regulates its ∼100 metabolic enzyme-coding gene targets. Using a dynamic perturbation approach, we elucidate the topology of the TrmB metabolic GRN in the model archaeon Halobacterium salinarum. Clustering of dynamic gene expression patterns reveals that TrmB functions alone to regulate central metabolic enzyme-coding genes but cooperates with various regulators to control peripheral metabolic pathways. Using a dynamical model, we predict gene expression patterns for some TrmB-dependent promoters and infer secondary regulators for others. Our data suggest feed-forward gene regulatory topology for cobalamin biosynthesis. In contrast, purine biosynthesis appears to require TrmB-independent regulators. We conclude that TrmB is an important component for mediating metabolic modularity, integrating nutrient status and regulating gene expression dynamics alone and in concert with secondary regulators. PMID:23892291

  17. Neuroimaging biomarkers to predict treatment response in schizophrenia: the end of 30 years of solitude?

    Science.gov (United States)

    Dazzan, Paola

    2014-12-01

    Studies that have used structural magnetic resonance imaging (MRI) suggest that individuals with psychoses have brain alterations, particularly in frontal and temporal cortices, and in the white matter tracts that connect them. Furthermore, these studies suggest that brain alterations may be particularly prominent, already at illness onset, in those individuals more likely to have poorer outcomes (eg, higher number of hospital admissions, and poorer symptom remission, level of functioning, and response to the first treatment with antipsychotic drugs). The fact that, even when present, these brain alterations are subtle and distributed in nature, has limited, until now, the utility of MRI in the clinical management of these disorders. More recently, MRI approaches, such as machine learning, have suggested that these neuroanatomical biomarkers can be used for direct clinical benefits. For example, using support vector machine, MRI data obtained at illness onset have been used to predict, with significant accuracy, whether a specific individual is likely to experience a remission of symptoms later on in the course of the illness. Taken together, this evidence suggests that validated, strong neuroanatomical markers could be used not only to inform tailored intervention strategies in a single individual, but also to allow patient stratification in clinical trials for new treatments. PMID:25733954

  18. Prolactin stress response does not predict brood desertion in a polyandrous shorebird.

    Science.gov (United States)

    Kosztolányi, András; Küpper, Clemens; Chastel, Olivier; Parenteau, Charline; Yılmaz, K Tuluhan; Miklósi, Adám; Székely, Tamás; Lendvai, Adám Z

    2012-05-01

    One of the fundamental principles of the life-history theory is that parents need to balance their resources between current and future offspring. Deserting the dependent young is a radical life-history decision that saves resources for future reproduction but that may cause the current brood to fail. Despite the importance of desertion for reproductive success, and thus fitness, the neuroendocrine mechanisms of brood desertion are largely unknown. We investigated two candidate hormones that may influence brood desertion in the Kentish plover Charadrius alexandrinus: prolactin ('parental hormone') and corticosterone ('stress hormone'). Kentish plovers exhibit an unusually diverse mating and parental care system: brood desertion occurs naturally since either parent (the male or the female) may desert the brood after the chicks hatch and mate with a new partner shortly after. We measured the hormone levels of parents at hatching using the standard capture and restraint protocol. We subsequently followed the broods to determine whether a parent deserted the chicks. We found no evidence that either baseline or stress-induced prolactin levels of male or female parents predicted brood desertion. Although stress-induced corticosterone levels were generally higher in females compared with males, individual corticosterone levels did not explain the probability of brood desertion. We suggest that, in this species, low prolactin levels do not trigger brood desertion. In general, we propose that the prolactin stress response does not reflect overall parental investment in a species where different parts of the breeding cycle are characterized by contrasting individual investment strategies.

  19. The predictive value of early treatment response in antipsychotic-naive patients with first-episode psychosis: Haloperidol versus olanzapine.

    Science.gov (United States)

    Rasmussen, Sean A; Rosebush, Patricia I; Anglin, Rebecca E; Mazurek, Michael F

    2016-07-30

    Early antipsychotic response predicts outcomes for psychotic patients, but recent evidence suggests that this may not be true for patients treated with olanzapine. In this study, we assessed the predictive value of early response to olanzapine or haloperidol in 75 antipsychotic-naive, first-episode psychosis inpatients. Patients were assessed weekly using the Brief Psychiatric Rating Scale (BPRS), Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A), and Young Mania Rating Scale (YMRS). Regression analyses were used to determine whether improvement at week 2 or week 3 predicted improvement at hospital discharge. The majority of patients in both groups experienced a decrease in symptom severity of ≥50% at week 2. In the haloperidol group, week 2 improvement predicted improvement at discharge for all measures except the HAM-A. In the olanzapine group, week 2 improvement only predicted improvement at discharge for HAM-D scores. However, week 3 improvement in the olanzapine group predicted improvement at discharge for all measures except the HAM-A. Olanzapine non-responders at week 3 (but not week 2) benefited from having olanzapine switched to another antipsychotic. These results suggest that a 2 week trial of haloperidol is sufficient to predict treatment outcomes, while a 3 week trial is required for olanzapine. PMID:27156027

  20. Predicting nutrient responses to mitigation at catchment to national scale: the UK research platform (Invited)

    Science.gov (United States)

    Johnes, P.

    2013-12-01

    Nutrient enrichment of waters from land-based and atmospheric sources presents a significant management challenge, requiring effective stakeholder engagement and policy development, properly underpinned by robust scientific evidence. The challenge is complex, raising significant questions about the specific sources, apportionment and pathways that determine nutrient enrichment and the key priorities for effective management and policy intervention. This paper presents outputs from 4 major UK research programmes: the Defra Demonstration Test Catchments programme (DTC), the Environment Agency's Catchment Sensitive Farming monitoring and evaluation programme (CSF), Natural Resources Wales Welsh Catchment Initiative (WCI) and the NERC Environmental Virtual Observatory programme (EVOp). Funded to meet this challenge, they are delivering new understanding of the rates and sources of pollutant fluxes from land to water, their impacts on ecosystem goods and services, and likely trends under future climate and land use change from field to national scale. DTC, a 12m investment by the UK Government, has set up long-term, high resolution research platforms equipped with novel telemetered sensor networks to monitor stream ecosystem responses to on-farm mitigation measures at a representative scale for catchment management. Ecosystem structural and functional responses and bulk hydrochemistry are also being monitored using standard protocols. CSF has set up long-term, enhanced monitoring in 8 priority catchments, with monthly monitoring in a further 72 English catchments and 6 Welsh priority catchments, to identify shifts in pollutant flux to waters resulting from mitigation measures in priority areas and farming sectors. CSF and WCI have contributed to >50 million of targeted farm improvements to date, representing a significant shift in farming practice. Each programme has generated detailed evidence on stream ecosystem responses to targeted mitigation. However, to provide

  1. Childhood trauma predicts antidepressant response in adults with major depression: data from the randomized international study to predict optimized treatment for depression.

    Science.gov (United States)

    Williams, L M; Debattista, C; Duchemin, A-M; Schatzberg, A F; Nemeroff, C B

    2016-01-01

    Few reliable predictors indicate which depressed individuals respond to antidepressants. Several studies suggest that a history of early-life trauma predicts poorer response to antidepressant therapy but results are variable and limited in adults. The major goal of the present study was to evaluate the role of early-life trauma in predicting acute response outcomes to antidepressants in a large sample of well-characterized patients with major depressive disorder (MDD). The international Study to Predict Optimized Treatment for Depression (iSPOT-D) is a randomized clinical trial with enrollment from December 2008 to January 2012 at eight academic and nine private clinical settings in five countries. Patients (n=1008) meeting DSM-IV criteria for MDD and 336 matched healthy controls comprised the study sample. Six participants withdrew due to serious adverse events. Randomization was to 8 weeks of treatment with escitalopram, sertraline or venlafaxine with dosage adjusted by the participant's treating clinician per routine clinical practice. Exposure to 18 types of traumatic events before the age of 18 was assessed using the Early-Life Stress Questionnaire. Impact of early-life stressors-overall trauma 'load' and specific type of abuse-on treatment outcomes measures: response: (⩾50% improvement on the 17-item Hamilton Rating Scale for Depression, HRSD17 or on the 16-item Quick Inventory of Depressive Symptomatology-Self-Rated, QIDS_SR16) and remission (score ⩽7 on the HRSD17 and ⩽5 on the QIDS_SR16). Trauma prevalence in MDD was compared with controls. Depressed participants were significantly more likely to report early-life stress than controls; 62.5% of MDD participants reported more than two traumatic events compared with 28.4% of controls. The higher rate of early-life trauma was most apparent for experiences of interpersonal violation (emotional, sexual and physical abuses). Abuse and notably abuse occurring at ⩽7 years of age predicted poorer outcomes

  2. Evaluation and prediction of material response during superplastic forming at various strain rates

    Science.gov (United States)

    Agarwal, Sumit

    constitutive response of the material. The simulations included grain boundary diffusion, grain boundary sliding and dislocation creep mechanisms. The predictions of simulations are in good agreement with the experimental results. The results agree with the transition in the mechanism of deformation with increasing strain rate, from grain boundary sliding to dislocation creep.

  3. Predicting Treatment Response for Oppositional Defiant and Conduct Disorder Using Pre-treatment Adrenal and Gonadal Hormones

    Science.gov (United States)

    Shenk, Chad E.; Dorn, Lorah D.; Kolko, David J.; Susman, Elizabeth J.; Noll, Jennie G.; Bukstein, Oscar G.

    2016-01-01

    Variations in adrenal and gonadal hormone profiles have been linked to increased rates of oppositional defiant disorder (ODD) and conduct disorder (CD). These relationships suggest that certain hormone profiles may be related to how well children respond to psychological treatments for ODD and CD. The current study assessed whether pre-treatment profiles of adrenal and gonadal hormones predicted response to psychological treatment of ODD and CD. One hundred five children, 6 – 11 years old, participating in a randomized, clinical trial provided samples for cortisol, testosterone, dehydroepiandrosterone, and androstenedione. Diagnostic interviews of ODD and CD were administered up to three years post-treatment to track treatment response. Group-based trajectory modeling identified two trajectories of treatment response: 1) a High-response trajectory where children demonstrated lower rates of an ODD or CD diagnosis throughout follow-up, and 2) a Low-response trajectory where children demonstrated higher rates of an ODD or CD diagnosis throughout follow-up. Hierarchical logistic regression predicting treatment response demonstrated that children with higher pre-treatment concentrations of testosterone were four times more likely to be in the Low-response trajectory. No other significant relationship existed between pre-treatment hormone profiles and treatment response. These results suggest that higher concentrations of testosterone are related to how well children diagnosed with ODD or CD respond to psychological treatment over the course of three years.

  4. FishMORPH - An agent-based model to predict salmonid growth and distribution responses under natural and low flows.

    Science.gov (United States)

    Phang, S C; Stillman, R A; Cucherousset, J; Britton, J R; Roberts, D; Beaumont, W R C; Gozlan, R E

    2016-01-01

    Predicting fish responses to modified flow regimes is becoming central to fisheries management. In this study we present an agent-based model (ABM) to predict the growth and distribution of young-of-the-year (YOY) and one-year-old (1+) Atlantic salmon and brown trout in response to flow change during summer. A field study of a real population during both natural and low flow conditions provided the simulation environment and validation patterns. Virtual fish were realistic both in terms of bioenergetics and feeding. We tested alternative movement rules to replicate observed patterns of body mass, growth rates, stretch distribution and patch occupancy patterns. Notably, there was no calibration of the model. Virtual fish prioritising consumption rates before predator avoidance replicated observed growth and distribution patterns better than a purely maximising consumption rule. Stream conditions of low predation and harsh winters provide ecological justification for the selection of this behaviour during summer months. Overall, the model was able to predict distribution and growth patterns well across both natural and low flow regimes. The model can be used to support management of salmonids by predicting population responses to predicted flow impacts and associated habitat change. PMID:27431787

  5. Brainstem frequency-following response recorded from one vertical and three horizontal electrode derivations.

    Science.gov (United States)

    Galbraith, G C; Bagasan, B; Sulahian, J

    2001-02-01

    The human brainstem frequency-following response reflects neural activity to periodic auditory stimuli. Responses were simultaneously recorded from one vertically oriented and three horizontally oriented electrode derivations. Nine participants each received a total of 16,000 tone repetitions, 4,000 for each of four stimulus frequencies: 222, 266, 350, and 450 Hz. The responses were digitally filtered, quantified by correlation and spectral analysis, and statistically evaluated by repeated measure analysis of variance. While the various horizontal derivation responses did not differ from each other in latency (values tightly clustered around M= 2.60 msec.), the vertical derivation response occurred significantly later (M=4.38 msec.). The smaller latency for the horizontal responses suggests an origin within the acoustic nerve, while the larger latency for the vertical response suggests a central brainstem origin. The largest response amplitude resulted from gold "tiptrode" electrodes placed in each auditory meatus, suggesting that this electrode derivation provided the most accurate (noninvasive) assessment of short-latency events originating at the level of the auditory nerve. PMID:11322612

  6. Prediction of Nitrogen Responses of Corn by Soil Nitrogen Mineralization Indicators

    Directory of Open Access Journals (Sweden)

    R.R. Simard

    2001-01-01

    Full Text Available Soil nitrogen mineralization potential (Nmin has to be spatially quantified to enable farmers to vary N fertilizer rates, optimize crop yields, and minimize N transfer from soils to the environment. The study objectives were to assess the spatial variability in soil Nmin potential based on clay and organic matter (OM contents and the impact of grouping soils using these criteria on corn grain (Zea mays L. yield, N uptake response curves to N fertilizer, and soil residual N. Four indicators were used: OM content and three equations involving OM and clay content. The study was conducted on a 15-ha field near Montreal, Quebec, Canada. In the spring 2000, soil samples (n = 150 were collected on a 30- x 30-m grid and six rates of N fertilizer (0 to 250 kg N ha-1 were applied. Kriged maps of particle size showed areas of clay, clay loam, and fine sandy loam soils. The Nmin indicators were spatially structured but soil nitrate (NO3– was not. The N fertilizer rate to reach maximum grain yield (Nmax, as estimated by a quadratic model, varied among textural classes and Nmin indicators, and ranged from 159 to 250 kg N ha-1. The proportion of variability (R2 and the standard error of the estimate (SE varied among textural groups and Nmin indicators. The R2 ranged from 0.53 to 0.91 and the SE from 0.13 to 1.62. Corn grain N uptake was significantly affected by N fertilizer and the pattern of response differed with soil texture. For the 50 kg N ha-1 rate, the apparent Nmin potential (ANM was significantly larger in the clay loam (122 kg ha-1 than in the fine sandy loam (80 kg ha-1 or clay (64 kg ha-1 soils. The fall soil residual N was not affected by N fertlizer inputs. Textural classes can be used to predict Nmax. The Nmin indicators may also assist the variable rate N fertilizer inputs for corn production.

  7. Prediction of nitrogen responses of corn by soil nitrogen mineralization indicators.

    Science.gov (United States)

    Simard, R R; Ziadi, N; Nolin, M C; Cambouris, A N

    2001-11-01

    Soil nitrogen mineralization potential (N min) has to be spatially quantified to enable farmers to vary N fertilizer rates, optimize crop yields, and minimize N transfer from soils to the environment. The study objectives were to assess the spatial variability in soil N min potential based on clay and organic matter (OM) contents and the impact of grouping soils using these criteria on corn grain (Zea mays L.) yield, N uptake response curves to N fertilizer, and soil residual N. Four indicators were used: OM content and three equations involving OM and clay content. The study was conducted on a 15-ha field near Montreal, Quebec, Canada. In the spring 2000, soil samples (n = 150) were collected on a 30- x 30-m grid and six rates of N fertilizer (0 to 250 kg N ha(-1)) were applied. Kriged maps of particle size showed areas of clay, clay loam, and fine sandy loam soils. The N min indicators were spatially structured but soil nitrate (NO3-) was not. The N fertilizer rate to reach maximum grain yield (N max), as estimated by a quadratic model, varied among textural classes and Nmin indicators, and ranged from 159 to 250 kg N ha(-1). The proportion of variability (R2) and the standard error of the estimate (SE) varied among textural groups and N min indicators. The R2 ranged from 0.53 to 0.91 and the SE from 0.13 to 1.62. Corn grain N uptake was significantly affected by N fertilizer and the pattern of response differed with soil texture. For the 50 kg N ha(-1) rate, the apparent N min potential (ANM) was significantly larger in the clay loam (122 kg ha(-1)) than in the fine sandy loam (80 kg ha(-1)) or clay (64 kg ha(-1)) soils. The fall soil residual N was not affected by N fertlizer inputs. Textural classes can be used to predict N max. The N min indicators may also assist the variable rate N fertilizer inputs for corn production. PMID:12805786

  8. A Global Genomic and Genetic Strategy to Predict Pathway Activation of Xenobiotic Responsive Transcription Factors in the Mouse Liver

    Science.gov (United States)

    Many drugs and environmentally-relevant chemicals activate xenobiotic-responsive transcription factors(TF). Identification of target genes of these factors would be useful in predicting pathway activation in in vitro chemical screening. Starting with a large compendium of Affymet...

  9. Evaluation of the serum free light chain (sFLC) analysis in prediction of response in symptomatic multiple myeloma patients

    DEFF Research Database (Denmark)

    Toftmann Hansen, Charlotte; Pedersen, Per T; Nielsen, Lars C;

    2014-01-01

    measurements of involved free light chains (iFLC) in prediction of high-quality responses. Measuring iFLC has a potential advantage due to a short half-life compared to the half-life of the M-protein. METHODS: In 36 multiple myeloma (MM) patients, we measured serial changes in iFLC and M-protein after start...

  10. Diffusion-weighted magnetic resonance imaging for the prediction of pathologic response to neoadjuvant chemoradiotherapy in esophageal cancer.

    NARCIS (Netherlands)

    Rossum, P.S. van; Lier, A.L. van; Vulpen, M. van; Reerink, O.; Lagendijk, J.J.; Lin, S.H.; Hillegersberg, R. van; Ruurda, J.P.; Meijer, G.J.; Lips, I.M.

    2015-01-01

    PURPOSE: To explore the value of diffusion-weighted magnetic resonance imaging (DW-MRI) for the prediction of pathologic response to neoadjuvant chemoradiotherapy (nCRT) in esophageal cancer. MATERIAL AND METHODS: In 20 patients receiving nCRT for esophageal cancer DW-MRI scanning was performed befo

  11. Predicting the profile of nutrients available for absorption: from nutrient requirement to animal response and environmental impact

    NARCIS (Netherlands)

    Dijkstra, J.; Kebreab, E.; Mills, J.A.N.; Pellikaan, W.F.; López, S.; Bannink, A.; France, J.

    2007-01-01

    Current feed evaluation systems for dairy cattle aim to match nutrient requirements with nutrient intake at pre-defined production levels. These systems were not developed to address, and are not suitable to predict, the responses to dietary changes in terms of production level and product compositi

  12. Can current moisture responses predict soil CO2 efflux under altered precipitation regimes? A synthesis of manipulation experiments

    DEFF Research Database (Denmark)

    Vicca, S.; Bahn, M.; Estiarte, M.;

    2014-01-01

    dependencies of SCE. Hence, the most justified answer to the question of whether current moisture responses of SCE can be extrapolated to predict SCE under altered precipitation regimes is 'no' - as based on the most reliable data sets available. We strongly recommend that future experiments focus more...

  13. Predicting Adaptive Response to Fadrozole Exposure: Computational Model of the Fathead Minnow Hypothalamic-Pituitary-Gonadal Axis

    Science.gov (United States)

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We are developing a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course (...

  14. Developing Predictive Approaches to Characterize Adaptive Responses of the Reproductive Endocrine Axis to Aromatase Inhibition: Computational Modeling

    Science.gov (United States)

    Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We developed a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course (DRTC)...

  15. Polymer Optical Fiber Sensor and the Prediction of Sensor Response Utilizing Artificial Neural Networks

    Science.gov (United States)

    Haroglu, Derya

    characteristics: reproducibility, accuracy, selectivity, aging, and resolution. Artificial neural network (ANN), a mathematical model formed by mimicking the human nervous system, was used to predict the sensor response. Qwiknet (version 2.23) software was used to develop ANNs and according to the results of Qwiknet the prediction performances for training and testing data sets were 75%, and 83.33% respectively. In this dissertation, Chapter 1 describes the worldwide plastic optical fiber (POF) and fiber optic sensor markets, and the existing textile structures used in fiber optic sensing design particularly for the applications of biomedical and structural health monitoring (SHM). Chapter 2 provides a literature review in detail on polymer optical fibers, fiber optic sensors, and occupancy sensing in the passenger seats of automobiles. Chapter 3 includes the research objectives. Chapter 4 presents the response of POF to tensile loading, bending, and cyclic tensile loading with discussion parts. Chapter 5 includes an e-mail based survey to prioritize customer needs in a Quality Function Deployment (QFD) format utilizing Analytic Hierarchy Process (AHP) and survey results. Chapter 6 describes the POF sensor design and the behavior of it under pressure. Chapter 7 provides a data analysis based on the experimental results of Chapter 6. Chapter 8 presents the summary of this study and recommendations for future work.

  16. Predictive value of serum cholinesterase for the prognosis of aged patients with systemic inflammatory response syndrome

    Institute of Scientific and Technical Information of China (English)

    JIN Qi-hui; HE Xiao-jun; LI Tian-lang; CHEN Huai-hong

    2011-01-01

    Background Some studies found that cholinesterase (ChE) can be an independent risk factor for patients with multiple organ dysfunction syndrome.To assess aged patients with systemic inflammatory response syndrome (SIRS) early and predict their prognosis,the predictive value of ChE for the prognosis of aged patients with SIRS was analyzed.Methods From September 2009 to September 2010,all aged patients with SIRS in the ICU of the Second Affiliated Hospital of Zhejiang University School of Medicine were retrospectively analyzed if they met inclusion criteria:patients aged >65 years and met American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference criteria for SIRS.Serum ChE,albumin,D-dimer,lactic acid and C-reactive protein (CRP) were measured,and the Acute Physiology and Chronic Health Evaluation (APACHE) Ⅱ and Glasgow Coma Scale (GCS) scores were evaluated within the first 24 hours in the ICU.Fisher's exact test was used for comparison of the primary disease between the deceased group and surviving group.For comparison of study variables between the two groups,the Student's t test or Mann-Whitney U test was used.Multivariate significance was tested with binary Logistic regression analysis.Results The clinical data of 124 aged patients with SIRS were collected and analyzed.Sixty-six patients (46 male,20female,mean age (78.70±8.08) years) who died were included in the deceased group and 58 patients (34 male,24female,mean age (76.02±6.57) years) who survived were included in the surviving group.There were no significant differences in age,gender,APACHE Ⅱ score and GCS score between the deceased group and surviving group (all P>0.05),but there were significant differences in lactic acid (P=0.011),D-dimer (P=0.011),albumin (P=0.007),CRP (P=0.008),and ChE (P <0.0001).The correlation analysis showed that the APACHE Ⅱ score and CRP were not correlated with ChE (both P <0.05).D-dimer and albumin were correlated with Ch

  17. Predicting beneficial effects of atomoxetine and citalopram on response inhibition in Parkinson's disease with clinical and neuroimaging measures.

    Science.gov (United States)

    Ye, Zheng; Rae, Charlotte L; Nombela, Cristina; Ham, Timothy; Rittman, Timothy; Jones, Peter Simon; Rodríguez, Patricia Vázquez; Coyle-Gilchrist, Ian; Regenthal, Ralf; Altena, Ellemarije; Housden, Charlotte R; Maxwell, Helen; Sahakian, Barbara J; Barker, Roger A; Robbins, Trevor W; Rowe, James B

    2016-03-01

    Recent studies indicate that selective noradrenergic (atomoxetine) and serotonergic (citalopram) reuptake inhibitors may improve response inhibition in selected patients with Parkinson's disease, restoring behavioral performance and brain activity. We reassessed the behavioral efficacy of these drugs in a larger cohort and developed predictive models to identify patient responders. We used a double-blind randomized three-way crossover design to investigate stopping efficiency in 34 patients with idiopathic Parkinson's disease after 40 mg atomoxetine, 30 mg citalopram, or placebo. Diffusion-weighted and functional imaging measured microstructural properties and regional brain activations, respectively. We confirmed that Parkinson's disease impairs response inhibition. Overall, drug effects on response inhibition varied substantially across patients at both behavioral and brain activity levels. We therefore built binary classifiers with leave-one-out cross-validation (LOOCV) to predict patients' responses in terms of improved stopping efficiency. We identified two optimal models: (1) a "clinical" model that predicted the response of an individual patient with 77-79% accuracy for atomoxetine and citalopram, using clinically available information including age, cognitive status, and levodopa equivalent dose, and a simple diffusion-weighted imaging scan; and (2) a "mechanistic" model that explained the behavioral response with 85% accuracy for each drug, using drug-induced changes of brain activations in the striatum and presupplementary motor area from functional imaging. These data support growing evidence for the role of noradrenaline and serotonin in inhibitory control. Although noradrenergic and serotonergic drugs have highly variable effects in patients with Parkinson's disease, the individual patient's response to each drug can be predicted using a pattern of clinical and neuroimaging features. PMID:26757216

  18. Person-Situation Effects and Gender Differences in the Prediction of Social Responsibility.

    Science.gov (United States)

    Witt, L. Alan

    1990-01-01

    Uses an 8-item Social Responsibility Scale to investigate social responsibility in a study involving 149 U.S. undergraduate students. Observes that satisfaction with the university and gratification delay are more powerful predictors of social responsibility among males. Identifies the socially responsible as those satisfied with an organization…

  19. Application of Response Surface Methodolody to Prediction of Dilution in Plasma Transferred Arc Hardfacing of Stainless Steel on Carbon Steel

    Institute of Scientific and Technical Information of China (English)

    V Balasubramanian; A K Lakshminarayanan; R Varahamoorthy; S Babu

    2009-01-01

    The application of.response surface methodology was highlighted to predict and optimize the percentage of dilution of iron-based hardfaced surface produced by the PTA (plasma transferred arc welding) process.The experiments were conducted based on five-factor five-level central composite rotatable design with full replication technique and a mathematical model was developed using response surface methodology.Furthermore,the response surface methodology was also used to optimize the process parameters that yielded the lowest percentage of dilution.

  20. Predicting response to preoperative chemotherapy agents by identifying drug action on modeled microRNA regulation networks.

    Directory of Open Access Journals (Sweden)

    Lida Zhu

    Full Text Available Identifying patients most responsive to specific chemotherapy agents in neoadjuvant settings can help to maximize the benefits of treatment and minimize unnecessary side effects. Metagene approaches that predict response based on gene expression signatures derived from an associative analysis of clinical data can identify chance associations caused by the heterogeneity of a tumor, leading to reproducibility issues in independent validations. In this study, to incorporate information from drug mechanisms of action, we explore the potential of microRNA regulation networks as a new feature space for identifying predictive markers. We introduce a measure we term the CoMi (Context-specific-miRNA-regulation pattern to represent a descriptive feature of the miRNA regulation network in the transcriptome. We examine whether the modifications to the CoMi pattern on specific biological processes are a useful representation of drug action by predicting the response to neoadjuvant Paclitaxel treatment in breast cancer and show that the drug counteracts the CoMi network dysregulation induced by tumorigenesis. We then generate a quantitative testbed to investigate the ability of the CoMi pattern to distinguish FDA approved breast cancer drugs from other FDA approved drugs not related to breast cancer. We also compare the ability of the CoMi and metagene methods to predict response to neoadjuvant Paclitaxel treatment in clinical cohorts. We find the CoMi method outperforms the metagene method, achieving area under curve (AUC values of 0.78 and 0.66 respectively. Furthermore, several of the predicted CoMi features highlight the network-based mechanism of drug resistance. Thus, our study suggests that explicitly modeling the drug action using network biology provides a promising approach for predictive marker discovery.

  1. From stiffness to strength in site response predictions: Formulation and validation of a hybrid hyperbolic nonlinear soil model

    Science.gov (United States)

    Asimaki, D.; Shi, J.

    2015-12-01

    Nonlinear site response analyses are becoming an increasingly important component of simulated ground motions intended for engineering applications. For regional-scale problems where geotechnical data are sparse, the challenge lies in computing nonlinear ground deformation to very strong ground shaking using a very small number of input parameters. We have developed a nonlinear model that addresses these issues: it simultaneously captures the soil's low-strain stiffness and large-strain strength of soil, and yields reliable predictions of soil response to weak and strong shaking using as sole input the shear wave velocity profile. We here present the formulation of the model and an extensive validation study based on downhole array recordings, with peak ground acceleration ranging from 0.01-0.9g. We also show that our model, referred to as hybrid hyperbolic, outperforms existing nonlinear formulations and simplified site response analyses widely used in practice for ground motions that induce more than 0.02% of soil strain (roughly equivalent to PGA higher than 0.02g). In addition to site-specific response predictions at sites with limited site characterization, the hybrid-hyperbolic model can help improve site amplification factors of ground motion prediction equations (GMPEs) by complementing the empirical data with simulated site response analyses for very strong ground shaking; as well as physics-based ground motion simulations, particularly for deeper sedimentary sites with low resonant frequencies.

  2. Dynamic contrast-enhanced magnetic resonance imaging for prediction of response to neoadjuvant chemotherapy in breast cancer

    Science.gov (United States)

    Fu, Juzhong; Fan, Ming; Zheng, Bin; Shao, Guoliang; Zhang, Juan; Li, Lihua

    2016-03-01

    Breast cancer is the second leading cause of women death in the United States. Currently, Neoadjuvant Chemotherapy (NAC) has become standard treatment paradigms for breast cancer patients. Therefore, it is important to find a reliable non-invasive assessment and prediction method which can evaluate and predict the response of NAC on breast cancer. The Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) approach can reflect dynamic distribution of contrast agent in tumor vessels, providing important basis for clinical diagnosis. In this study, the efficacy of DCE-MRI on evaluation and prediction of response to NAC in breast cancer was investigated. To this end, fifty-seven cases of malignant breast cancers with MRI examination both before and after two cycle of NAC were analyzed. After pre-processing approach for segmenting breast lesions and background regions, 126-dimensional imaging features were extracted from DCE-MRI. Statistical analyses were then performed to evaluate the associations between the extracted DCE-MRI features and the response to NAC. Specifically, pairwise t test was used to calculate differences of imaging features between MRI examinations before-and-after NAC. Moreover, the associations of these image features with response to NAC were assessed using logistic regression. Significant association are found between response to NAC and the features of lesion morphology and background parenchymal enhancement, especially the feature of background enhancement in normal side of breast (P=0.011). Our study indicate that DCE-MRI features can provide candidate imaging markers to predict response of NAC in breast cancer.

  3. Predictive factors of clinical response in steroid-refractory ulcerative colitis treated with granulocyte-monocyte apheresis

    Institute of Scientific and Technical Information of China (English)

    Valeria D'Ovidio; Donatella Meo; Angelo Viscido; Giampaolo Bresci; Piero Vernia; Renzo Caprilli

    2011-01-01

    AIM: To identify factors predicting the clinical response of ulcerative colitis patients to granulocyte-monocyte apheresis (GMA).METHODS: Sixty-nine ulcerative colitis patients (39 F, 30 M) dependent upon/refractory to steroids were treated with GMA.Steroid dependency, clinical activity index (CAI), C reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), values at baseline, use of immunosuppressant, duration of disease, and age and extent of disease were considered for statistical analysis as predictive factors of clinical response.Univariate and multivariate logistic regression models were used.RESULTS: In the univariate analysis, CAI (P = 0.039) and ESR (P = 0.017) levels at baseline were singled out as predictive of clinical remission.In the multivariate analysis steroid dependency [Odds ratio (OR) = 0.390, 95% Confidence interval (CI): 0.176-0.865, Wald 5.361, P = 0.0160] and low CAI levels at baseline (4 < CAI < 7) (OR = 0.770, 95% CI: 0.425-1.394, Wald 3.747, P = 0.028) proved to be effective as factors predicting clinical response.CONCLUSION: GMA may be a valid therapeutic option for steroid-dependent ulcerative colitis patients with mild-moderate disease and its clinical efficacy seems to persist for 12 mo.

  4. Peritraumatic startle response predicts the vulnerability to develop PTSD-like behaviors in rats: a model for peritraumatic dissociation

    Directory of Open Access Journals (Sweden)

    Xinwen eDong

    2014-01-01

    Full Text Available Peritraumatic dissociation, a state characterized by alteration in perception and reduced awareness of surroundings, is considered to be a risk factor for the development of post-traumatic stress disorder (PTSD. However, the predictive ability of peritraumatic dissociation is questioned for the inconsistent results in different time points of assessment. The startle reflex is an objective behavioral measurement of defensive response to abrupt and intense sensory stimulus of surroundings, with potential to be used as an assessment on the dissociative status in both humans and rodents. The present study examined the predictive effect of acoustic startle response (ASR in different time points around the traumatic event in an animal model of PTSD. The PTSD-like symptoms, including hyperarousal, avoidance, and contextual fear, were assessed 2-3 weeks post-trauma. The results showed that 1 the startle amplitude attenuated immediate after intense footshock in almost half of the stress animals, 2 the attenuated startle responses at 1 hour but not 24 hours after stress predicted the development of severe PTSD-like symptoms. These data indicate that the startle alteration at the immediate period after trauma, including 1 hour, is more important in PTSD prediction than 24 hours after trauma. Our study also suggests that the startle attenuation immediate after intense stress may serve as an objective measurement of peritraumatic dissociation in rats.

  5. HER family kinase domain mutations promote tumor progression and can predict response to treatment in human breast cancer

    KAUST Repository

    Boulbes, Delphine R.

    2014-11-11

    Resistance to HER2-targeted therapies remains a major obstacle in the treatment of HER2-overexpressing breast cancer. Understanding the molecular pathways that contribute to the development of drug resistance is needed to improve the clinical utility of novel agents, and to predict the success of targeted personalized therapy based on tumor-specific mutations. Little is known about the clinical significance of HER family mutations in breast cancer. Because mutations within HER1/EGFR are predictive of response to tyrosine kinase inhibitors (TKI) in lung cancer, we investigated whether mutations in HER family kinase domains are predictive of response to targeted therapy in HER2-overexpressing breast cancer. We sequenced the HER family kinase domains from 76 HER2-overexpressing invasive carcinomas and identified 12 missense variants. Patients whose tumors carried any of these mutations did not respond to HER2 directed therapy in the metastatic setting. We developed mutant cell lines and used structural analyses to determine whether changes in protein conformation could explain the lack of response to therapy. We also functionally studied all HER2 mutants and showed that they conferred an aggressive phenotype and altered effects of the TKI lapatinib. Our data demonstrate that mutations in the finely tuned HER kinase domains play a critical function in breast cancer progression and may serve as prognostic and predictive markers.

  6. Predicting the Responses of Soil Nitrite-Oxidizers to Multi-Factorial Global Change: A Trait-Based Approach

    Science.gov (United States)

    Le Roux, Xavier; Bouskill, Nicholas J.; Niboyet, Audrey; Barthes, Laure; Dijkstra, Paul; Field, Chris B.; Hungate, Bruce A.; Lerondelle, Catherine; Pommier, Thomas; Tang, Jinyun; Terada, Akihiko; Tourna, Maria; Poly, Franck

    2016-01-01

    Soil microbial diversity is huge and a few grams of soil contain more bacterial taxa than there are bird species on Earth. This high diversity often makes predicting the responses of soil bacteria to environmental change intractable and restricts our capacity to predict the responses of soil functions to global change. Here, using a long-term field experiment in a California grassland, we studied the main and interactive effects of three global change factors (increased atmospheric CO2 concentration, precipitation and nitrogen addition, and all their factorial combinations, based on global change scenarios for central California) on the potential activity, abundance and dominant taxa of soil nitrite-oxidizing bacteria (NOB). Using a trait-based model, we then tested whether categorizing NOB into a few functional groups unified by physiological traits enables understanding and predicting how soil NOB respond to global environmental change. Contrasted responses to global change treatments were observed between three main NOB functional types. In particular, putatively mixotrophic Nitrobacter, rare under most treatments, became dominant under the ‘High CO2+Nitrogen+Precipitation’ treatment. The mechanistic trait-based model, which simulated ecological niches of NOB types consistent with previous ecophysiological reports, helped predicting the observed effects of global change on NOB and elucidating the underlying biotic and abiotic controls. Our results are a starting point for representing the overwhelming diversity of soil bacteria by a few functional types that can be incorporated into models of terrestrial ecosystems and biogeochemical processes. PMID:27242680

  7. Predictive Biomarkers of Bacillus Calmette-Guérin Immunotherapy Response in Bladder Cancer: Where Are We Now?

    Directory of Open Access Journals (Sweden)

    Luís Lima

    2012-01-01

    Full Text Available The most effective therapeutic option for managing nonmuscle invasive bladder cancer (NMIBC, over the last 30 years, consists of intravesical instillations with the attenuated strain Bacillus Calmette-Guérin (the BCG vaccine. This has been performed as an adjuvant therapeutic to transurethral resection of bladder tumour (TURBT and mostly directed towards patients with high-grade tumours, T1 tumours, and in situ carcinomas. However, from 20% to 40% of the patients do not respond and frequently present tumour progression. Since BCG effectiveness is unpredictable, it is important to find consistent biomarkers that can aid either in the prediction of the outcome and/or side effects development. Accordingly, we conducted a systematic critical review to identify the most preeminent predictive molecular markers associated with BCG response. To the best of our knowledge, this is the first review exclusively focusing on predictive biomarkers for BCG treatment outcome. Using a specific query, 1324 abstracts were gathered, then inclusion/exclusion criteria were applied, and finally 87 manuscripts were included. Several molecules, including CD68 and genetic polymorphisms, have been identified as promising surrogate biomarkers. Combinatory analysis of the candidate predictive markers is a crucial step to create a predictive profile of treatment response.

  8. Monte-Carlo based prediction of radiochromic film response for hadrontherapy dosimetry

    International Nuclear Information System (INIS)

    A model has been developed to calculate MD-55-V2 radiochromic film response to ion irradiation. This model is based on photon film response and film saturation by high local energy deposition computed by Monte-Carlo simulation. We have studied the response of the film to photon irradiation and we proposed a calculation method for hadron beams.

  9. A mechanically coupled reaction-diffusion model for predicting the response of breast tumors to neoadjuvant chemotherapy

    Science.gov (United States)

    Weis, Jared A.; Miga, Michael I.; Arlinghaus, Lori R.; Li, Xia; Bapsi Chakravarthy, A.; Abramson, Vandana; Farley, Jaime; Yankeelov, Thomas E.

    2013-09-01

    There is currently a paucity of reliable techniques for predicting the response of breast tumors to neoadjuvant chemotherapy. The standard approach is to monitor gross changes in tumor size as measured by physical exam and/or conventional imaging, but these methods generally do not show whether a tumor is responding until the patient has received many treatment cycles. One promising approach to address this clinical need is to integrate quantitative in vivo imaging data into biomathematical models of tumor growth in order to predict eventual response based on early measurements during therapy. In this work, we illustrate a novel biomechanical mathematical modeling approach in which contrast enhanced and diffusion weighted magnetic resonance imaging data acquired before and after the first cycle of neoadjuvant therapy are used to calibrate a patient-specific response model which subsequently is used to predict patient outcome at the conclusion of therapy. We present a modification of the reaction-diffusion tumor growth model whereby mechanical coupling to the surrounding tissue stiffness is incorporated via restricted cell diffusion. We use simulations and experimental data to illustrate how incorporating tissue mechanical properties leads to qualitatively and quantitatively different tumor growth patterns than when such properties are ignored. We apply the approach to patient data in a preliminary dataset of eight patients exhibiting a varying degree of responsiveness to neoadjuvant therapy, and we show that the mechanically coupled reaction-diffusion tumor growth model, when projected forward, more accurately predicts residual tumor burden at the conclusion of therapy than the non-mechanically coupled model. The