Fast VMAT planning for prostate radiotherapy: dosimetric validation of a deep learning-based initial segment generation method.

Objective. To develop and evaluate a deep learning based fast volumetric modulated arc therapy (VMAT) plan generation method for prostate radiotherapy.Approach. A customized 3D U-Net was trained and validated to predict initial segments at 90 evenly distributed control points of an arc, linked to our research treatment planning system (TPS) for segment shape optimization (SSO) and segment weight optimization (SWO). For 27 test patients, the VMAT plans generated based on the deep learning prediction (VMATDL) were compared with VMAT plans generated with a previously validated automated treatment planning method (VMATref). For all test cases, the deep learning prediction accuracy, plan dosimetric quality, and the planning efficiency were quantified and analyzed.Main results. For all 27 test cases, the resulting plans were clinically acceptable. TheV95%for the PTV2 was greater than 99%, and theV107%was below 0.2%. Statistically significant difference in target coverage was not observed between the VMATrefand VMATDLplans (P = 0.3243 > 0.05). The dose sparing effect to the OARs between the two groups of plans was similar. Small differences were only observed for the Dmean of rectum and anus. Compared to the VMATref, the VMATDLreduced 29.3% of the optimization time on average.Significance. A fully automated VMAT plan generation method may result in significant improvement in prostate treatment planning efficiency. Due to the clinically acceptable dosimetric quality and high efficiency, it could potentially be used for clinical planning application and real-time adaptive therapy application after further validation.

NDI: A Platform-Independent Data Interface and Database for Neuroscience Physiology and Imaging Experiments.

Collaboration in neuroscience is impeded by the difficulty of sharing primary data, results, and software across labs. Here, we introduce Neuroscience Data Interface (NDI), a platform-independent standard that allows an analyst to use and create software that functions independently from the format of the raw data or the manner in which the data are organized into files. The interface is rooted in a simple vocabulary that describes common apparatus and storage devices used in neuroscience experiments. Results of analyses, and analyses of analyses, are stored as documents in a scalable, queryable database that stores the relationships and history among the experiment elements and documents. The interface allows the development of an application ecosystem where applications can focus on calculation rather than data format or organization. This tool can be used by individual labs to exchange and analyze data, and it can serve to curate neuroscience data for searchable archives.

Deciphering the nutritive and antioxidant properties of Malay cherry (Lepisanthes alata) fruit dominated by ripening effects.

In this study, Malay cherry fruit were explored for the changes in their nutritive and phenolic compositions upon ripening (unripe and ripe stages). Nutritive compositions (sugars, proteins, and fats) of the fruit increased, whilst organic acids of the fruit decreased in ripe fruit. Twenty-eight non-anthocyanin phenolics of the fruit were identified by the high-performance liquid chromatography-high resolution-time of flight mass spectrometry (HPLC-HR-TOF/MS2). Among them, quercetin-3-O-rutinoside and quercetin-3-O-glucoside are dominant species in the unripe fruit, and four more phenolics are shown in the ripe fruit. Additionally, seventeen anthocyanins were solely identified in the ripe fruit. This could be the signature phenolic profile of Malay cherry fruit. The total phenolics and total proanthocyanidins of the fruit significantly decreased upon ripening. Consistently, antioxidant capacities of the fruit also decreased upon ripening. Our results suggest unripe fruit are good sources of phenolic antioxidants that are worthwhile for utilisation as functional food sources.

[Comparative analysis of 226 Hz and 1 000 Hz probe tone tympanometry in infants].

OBJECTIVE: To analyze the judgement standard and evaluate the diagnostic value of the low frequency and high frequency tympanometry in infants with otitis media. METHOD: Tympanograms for admittance with 226 Hz and 1 000 Hz probe tones and resonant frequency were obtained from normal infants (195 cases, 321 ears) and infants with otitis media(122 cases, 171 ears). The mean, standard deviation, median, 5% quantile, 95% quantile and 95% confidence interval of peak admittance, gradient and resonant frequency were measured and calculated in different age groups. The significant differences of 1000 Hz peak admittance, 226 Hz peak admittance and gradient between normal infants and infants with otitis median were analyzed using SPSS 11.0. The false positive rate and the false negative rate of different age groups in infants with otitis media were evaluated according to such judgement standards as 1000 Hz peak admittance, 226Hz peak admittance or gradient. RESULT: The false positive rate and the false negative rate of the 1000 Hz probe tone tympanometry in infants with otitis media unter one year of age were 3.07% and 1.84% as the normal range of positive peak was more than 0.2 mmho. The false positive rate and the false negative rate of the 1000 Hz probe tone tympanometry in infants with otitis media aged 1-2 years and aged 2-3 years were 3.26%, 5.26% and 1.52%, 0.00% respectively,as the normal range of positive peak was more than 0.3 mmho. These was no significant difference in the gradient with 226 Hz probe tone between normal infants and infants with otitis median under one year of age. The false positive rate and the false negative rate of the 226 Hz probe tone tympanometry in infants with otitis media aged 1-2 years and aged 2-3 years were 44.57%, 31.58% and 16.67%, 6.67% respectively, as the gradient with 226 Hz probe tone was a judgement standard. CONCLUSION: (1) The diagnostic accuracy of tympanometry with 1000 Hz probe tone for otitis media in infants younger than 3 years of age exceeded 226 Hz probe tone tympanometry, the 1000 Hz probe tone tympanometry is suggested to the evaluation of middle ear function in infants before 3 years. (2) It is reasonable that the normal range of positive peak is more than 0.2 mmho in infants unter one year of age and the normal range of positive peak is more than 0.3 mmho in infants aged 1-3 years.

[Effects of tympanic membrane perforation on real-ear to coupler difference].

OBJECTIVE: To investigate the effects of tympanic membrane perforation on real-ear to coupler difference (RECD) in adults. METHOD: RECD was measured in 34 ears with dry tympanic membrane perforation, 34 normal subjects served as controls. RESULT: There was significant difference (P<0.05) below 1 kHz (including 1 kHz) and in 4 kHz between experimental group and control group. For perforated ears, RECD was 3.5-15 dB less from 250 Hz to 1 kHz while the values of RECD was negative from 250 Hz to 750 Hz. A larger standard deviation was found in experimental group. The mean intra-subject standard deviation was 4.4 dB in experimental group as contrasted with 1.4 dB in control group. The equivalent ear canal volume appeared to be negatively correlated with the RECD reduction below 0.75 kHz and no correlation above 1 kHz. The more the equivalent ear canal volume, the smaller the RECD. It was found that the size of tympanic membrane perforation had no effect on RECD. CONCLUSION: It is recommended to perform real-ear measurement individually instead of using the age-appropriate average values, and to increase low frequency gain appropriately when fitting hearing aids for patients with dry tympanic membrane perforation.

[Follow-up examination for newborns and infants who failed hearing screening].

OBJECTIVE: To investigate the hearing change and the characteristic of hearing thresholds of the infants failing in the hearing screening. METHOD: ABR,DPOAE and acoustic immittance were used to test infants failing in the screening in their third month and the sixth month, whose results were compared. RESULT: In the third month the false positive rate of DPOAE test was 9.6%. Comparing with the results tested in the third month, the degree of severe hearing loss retested in the sixth month did not change much. But the percentage of the slight-moderate hearing loss improvement to normal or better was higher. Comparing ABR threshold result in the third month and that in the sixth month, t = 3.496, P <0.01 in the left ear, and t = 5.572, P <0.01 in the right ear, respectively. There was significant difference between these results. CONCLUSION: The new-borns failing DPOAE can not be just considered to identifying hearing loss,and it must be with the ABR to make the diagnosis. It is feasible to diagnose severe-profound hearing loss in the third month and interfere before the sixth month, but the infants with mild-moderate hearing loss must undertake the auditory tests more than twice and be followed up in more than half a year, then we can make diagnosis according to the audiologic evaluations results and the daily behaviors.