Binary optimization
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In recent years, several computer-aided diagnosis systems emerged for the diagnosis of thyroid gland disorders using ultrasound imaging. These systems based on machine learning algorithms may offer a second opinion to radiologists by evaluating a malignancy risk of thyroid tissue, thus increasing the overall diagnostic accuracy of ultrasound imaging. Although current computer-aided diagnosis systems exhibit promising results, their use in clinical practice is limited. One of the main limitations is that the majority of them use direction-dependent features. Our intention has been to design a computer-aided diagnosis system, which will use only direction-independent features, that is, it will not be dependent on the orientation and the inclination angle of the ultrasound probe when acquiring the image. We have, therefore, applied histogram analysis and segmentation-based fractal texture analysis algorithm, which calculates direction-independent features only. In our study, 40 thyroid nodules (20 malignant and 20 benign) were used to extract several features, such as histogram parameters, fractal dimension, and mean brightness value in different grayscale bands (obtained by 2-threshold binary decomposition). The features were then used in support vector machine and random forests classifiers to differentiate nodules into malignant and benign classes. Using leave-one-out cross-validation method, the overall accuracy was 92.42% for random forests and 94.64% for support vector machine. Results show that both methods are useful in practice; however, support vector machine provides better results for this application. Proposed computer-aided diagnosis system can provide support to radiologists in their current diagnosis of thyroid nodules, whereby it can optimize the overall accuracy of ultrasound imaging.
- MeSH
- algoritmy * MeSH
- diagnóza počítačová metody MeSH
- diferenciální diagnóza MeSH
- interpretace obrazu počítačem metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- štítná žláza diagnostické zobrazování patologie MeSH
- support vector machine MeSH
- ultrasonografie metody MeSH
- uzly štítné žlázy klasifikace diagnostické zobrazování patologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
The spawning and well-being of fish in an ecosystem are closely linked to climatic cues, viz., temperature and rainfall. Reduced fitness can affect the reproductive performance and lead to skipped spawning. Benchmarking the threshold fitness required for a fish population to achieve readiness for spawning, and understanding how climatic parameters influence the fitness will aid in predicting the fate of its reproductive success in future climatic conditions. This study determined the threshold condition factor pre-spawning fitness (Kspawn50) at which 50% of the female Channa punctata population can be deemed fit for spawning. The optimal climate within which pre-spawning fitness is attained by this species under Indian climatic conditions was also identified. The study was conducted from June 2015 to September 2016, covering two spawning seasons (June-August) in a Gangetic floodplain wetland of West Bengal, India. The non-parametric Kaplan-Meier method (survival fit) was used for estimation of pre-spawning fitness. "Ready to spawn" females were classified based on binary coding of the gonadal maturity stages. The thermal and precipitation range within which spawning fitness is achieved was identified by using the locally weighted smoothing technique. Female C. punctata pre-spawning fitness (Kspawn50) ranged from 1.26 to 1.39 with an estimated median of 1.29 units. Temperatures between 29 and 32 °C and rainfall above 100 mm were conducive to attaining the requisite pre-spawning fitness in C. punctata. This is the first study benchmarking the pre-spawning fitness and optimal climate for C. punctata. Understanding spawning requirements can inform the climate change-induced impacts on reproductive plasticity and evolutionary adaptations of snakeheads in the Ganga river basin.
- MeSH
- ekosystém * MeSH
- klimatické změny MeSH
- mokřady * MeSH
- řeky MeSH
- rozmnožování MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Indie MeSH
Z důvodu omezené dostupnosti přípravků průmyslově vyráběných s obsahem lokálního anestetika určených k aplikaci na kůži a zvýšené poptávky po lidokainovém gelu použitelném před aplikací přípravku s obsahem kapsaicinu určeného k léčbě neuropatické bolesti se nabízí možnost magistraliter přípravy topického polotuhého přípravku s obsahem lokálního anestetika. Cílem bylo připravit směsný systém hydrogelu s vemulgovaným léčivem, využít látky snižující teplotu tání lidokainu a vytvořit eutektickou směs s vysokou koncentrací lidokainu, která tvoří olejovou fázi systému. Dle údajů ze zahraniční literatury byl pro vytvoření binární eutektické směsi s lidokainem zvolen thymol a za přídavku dalších pomocných látek formulován emulzní systém s vemulgovaným léčivem v lipofilní fázi stabilizovaný komplexním neiontovým emulgátorem a karbomerem. Pro vyhovující anestezující účinnost je dále třeba upravit hodnotu pH přípravku. Vhodnou zásaditě reagující látkou byl zvolen trometamol. Na základě přídavku různých množství trometamolu bylo následně měřeno pH jednotlivých vzorků emulgelů a v porovnání s hodnotou pH přípravku EMLA pak vytvořeno výsledné složení lidokainového emulgelu. Při formulaci receptury byl brán zřetel na praktičnost a dostupnost obsažených látek. Všechny složky jsou k dispozici pro přípravu léčivých přípravků v České republice s příslušným certifikátem jakosti. Receptura 5% lidokainového emulgelu s hodnotou pH cca 9,1 je formulována na bázi gelotvorné látky karbomeru s vemulgovanou olejovou fází představovanou eutektickou směsí lidokainu s thymolem, za přídavku ethanolu a propylenglykolu, stabilizovaného komplexním emulgátorem. Výhodou je absence přísady jiného lokálního anestetika.
Due to a limited availability of industrially manufactured products containing local anesthetics for skin application and an increased demand for lidocaine-containing gel applicable prior to a product containing capsaicin for neuropathic pain treatment, it is necessary to prepare a topical semi-solid preparation containing the local anesthetic in pharmacies. Our aim was to create a mixed system of a hydrophilic gel with the emulsified drug, using excipients to decrease the lidocaine melting point, thereby creating a eutectic mixture with a high concentration of lidocaine in the oil phase. Based on bibliographic data, thymol creating a binary eutectic system containing lidocaine has been chosen. After addition of other excipients, an emulsion system was prepared and the drug was stabilized in the oil phase by a mixed nonionic emulsifier and carbomera. For the optimal anesthetic effects, the pH value should be adjusted; trometamol has been chosen as a suitable basic reacting excipient. Based on the addition of different amounts of trometamol, pH values of individual emulgels have been measured and the final composition of lidocaine emulgel has been created. A recipe for a 5 % lidocaine emulgel with the pH value of 9.1 has been created, based on the gel-forming substance carbomera with an emulsion of the oil phase containing a eutectic mixture of lidocaine and thymol, with an addition of ethanol and propylenglycol, stabilized by a mixed nonionic emulsifier. The advantage is the absence of other local anesthetics.
- Klíčová slova
- binary eutectic mixture,
- MeSH
- anestetika lokální * MeSH
- aplikace kožní * MeSH
- aplikace lokální MeSH
- dermatologické látky MeSH
- elektronová mikroskopie * MeSH
- emulze MeSH
- hydrogely MeSH
- kapsaicin MeSH
- lidé MeSH
- lidokain * MeSH
- okluzivní ošetření rány * MeSH
- povrchově aktivní látky MeSH
- příprava léků * MeSH
- schvalování léčiv MeSH
- thymol MeSH
- Check Tag
- lidé MeSH
- Geografické názvy
- Česká republika MeSH
This paper focuses on wrapper-based feature selection for a 1-nearest neighbor classifier. We consider in particular the case of a small sample size with a few hundred instances, which is common in biomedical applications. We propose a technique for calculating the complete bootstrap for a 1-nearest-neighbor classifier (i.e., averaging over all desired test/train partitions of the data). The complete bootstrap and the complete cross-validation error estimate with lower variance are applied as novel selection criteria and are compared with the standard bootstrap and cross-validation in combination with three optimization techniques - sequential forward selection (SFS), binary particle swarm optimization (BPSO) and simplified social impact theory based optimization (SSITO). The experimental comparison based on ten datasets draws the following conclusions: for all three search methods examined here, the complete criteria are a significantly better choice than standard 2-fold cross-validation, 10-fold cross-validation and bootstrap with 50 trials irrespective of the selected output number of iterations. All the complete criterion-based 1NN wrappers with SFS search performed better than the widely-used FILTER and SIMBA methods. We also demonstrate the benefits and properties of our approaches on an important and novel real-world application of automatic detection of the subthalamic nucleus.
- MeSH
- teoretické modely MeSH
- velikost vzorku * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- validační studie MeSH
... Likelihood Methods 5 -- 1.3 Bayesian Methods 12 -- 1.4 Deterministic Numerical Methods 19 -- 1.4.1 Optimization ... ... -- 2.1.1 Uniform Simulation 36 r 2.1.2 The Inverse Transform 38 i 2.1.3 Alternatives 40 -- 2.1.4 Optimal ... ... - XX Contents -- 7.4.2 A Metropolis-Hastings Version of ARS 285 -- 7.5 Random Walks 287 -- 7.6 Optimization ... ... and Control 292 -- 7.6.1 Optimizing the Acceptance Rate 292 -- 7.6.2 Conditioning and Accelerations ... ... Between Variances 497 -- 12.3.5 Effective Sample Size 499 -- 12.4 Simultaneous Monitoring 500 -- 12.4.1 Binary ...
Springer texts in statistics
2nd ed. xxx, 645 s., grafy
Capillary liquid chromatography (cLC) hyphenated with tandem mass spectrometry (MS-MS) was used to separate and quantitate trace concentrations of five estrogens in aqueous samples. New C(18)-based sorption materials bound to the silica support by monomeric and polymeric mechanisms were compared and tested for solid-phase extraction (SPE) of selected analytes with respect to optimization of their preconcentration yield. Application of an endcapped, monomer-bound preconcentration Discovery DSC-18Lt column under the optimized conditions provides yields in the range from 95 to 100% with a high repeatability (n=3, RSD≤7.2%). Using the electrospray ionization in the positive mode (ESI+), the cLC-MS-MS system (the Zorbax SB C18 capillary column and a binary mobile phase of acetonitrile and water containing 0.1% formic acid in both the components) was optimized to attain a sufficient retention of the early eluting estriol, a satisfactory resolution of the analytes and the maximum sensitivity of the determination. Both the isocratic and gradient elution were used and the optimized gradient method permitted analyses of aqueous environmental samples in 14 min within a linearity range from 6.1 to 25.0 (LOQ of analytes) to 500 ng/L and with a very good linearity (r>0.9981) for all the estrogens studied. The detection limits are in the range from 3.0 to 6.8 ng/L (1 μL injection volume). Six environmental water samples were analyzed and the studied estrogens were found in the Vltava river sample collected in Prague (13.2 ng/L for 17β-estradiol) and in the inlet to the wastewater treatment plant in Prague, at an overall concentration of 371.4 ng/L.
- MeSH
- chemické látky znečišťující vodu analýza MeSH
- estrogeny analýza izolace a purifikace MeSH
- extrakce na pevné fázi metody MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
- kapilární elektrochromatografie metody MeSH
- lineární modely MeSH
- řeky chemie MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- tandemová hmotnostní spektrometrie metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Endometrial biopsies are important in the diagnostic workup of women who present with abnormal uterine bleeding or hereditary risk of endometrial cancer. In general, approximately 10% of all endometrial biopsies demonstrate endometrial (pre)malignancy that requires specific treatment. As the diagnostic evaluation of mostly benign cases results in a substantial workload for pathologists, artificial intelligence (AI)-assisted preselection of biopsies could optimize the workflow. This study aimed to assess the feasibility of AI-assisted diagnosis for endometrial biopsies (endometrial Pipelle biopsy computer-aided diagnosis), trained on daily-practice whole-slide images instead of highly selected images. Endometrial biopsies were classified into 6 clinically relevant categories defined as follows: nonrepresentative, normal, nonneoplastic, hyperplasia without atypia, hyperplasia with atypia, and malignant. The agreement among 15 pathologists, within these classifications, was evaluated in 91 endometrial biopsies. Next, an algorithm (trained on a total of 2819 endometrial biopsies) rated the same 91 cases, and we compared its performance using the pathologist's classification as the reference standard. The interrater reliability among pathologists was moderate with a mean Cohen's kappa of 0.51, whereas for a binary classification into benign vs (pre)malignant, the agreement was substantial with a mean Cohen's kappa of 0.66. The AI algorithm performed slightly worse for the 6 categories with a moderate Cohen's kappa of 0.43 but was comparable for the binary classification with a substantial Cohen's kappa of 0.65. AI-assisted diagnosis of endometrial biopsies was demonstrated to be feasible in discriminating between benign and (pre)malignant endometrial tissues, even when trained on unselected cases. Endometrial premalignancies remain challenging for both pathologists and AI algorithms. Future steps to improve reliability of the diagnosis are needed to achieve a more refined AI-assisted diagnostic solution for endometrial biopsies that covers both premalignant and malignant diagnoses.
- MeSH
- biopsie MeSH
- hyperplazie MeSH
- lidé MeSH
- počítače * MeSH
- reprodukovatelnost výsledků MeSH
- studie proveditelnosti MeSH
- umělá inteligence * MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Fascial healing following acute injury, such as that occurring during surgical procedures, is defined functionally. For example, failure of fascial healing following celiotomy is only identified when incisional hernias are diagnosed. Such hernias incur billions of dollars per year in medical costs. Despite the importance of fascial healing, there is a paucity of data regarding the quality such healing. In clinical settings, the quantification of fascial wound healing is limited to a binary state: either there is no clinically apparent functional deficit and full fascia healing is assumed, or an incisional hernia or other functional failure is visible and the fascia did not heal. There are no clinical methods to isolate and functionally test fascia in patients. Recent studies have revealed unexpected findings regarding the recovery of tensile strength, specific surgical methods that optimize fascial healing, and the potential impact of biological pharmaceuticals in eliminating fascial healing failure. However, much remains unknown about the biology of fascial healing.
- MeSH
- břišní svaly patologie chirurgie MeSH
- dehiscence operační rány patologie MeSH
- fascie patologie MeSH
- fasciotomie MeSH
- hojení ran * MeSH
- imunohistochemie MeSH
- kůže patologie MeSH
- lidé MeSH
- pevnost v tahu MeSH
- pooperační komplikace patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The bioavailability of poorly water-soluble active pharmaceutical ingredients (APIs) can be improved via the formulation of an amorphous solid dispersion (ASD), where the API is incorporated into a suitable polymeric carrier. Optimal carriers that exhibit good compatibility (i.e., solubility and miscibility) with given APIs are typically identified through experimental means, which are routinely labor- and cost-inefficient. Therefore, the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state, a popular thermodynamic model in pharmaceutical applications, is examined in terms of its performance regarding the computational pure prediction of API-polymer compatibility based on activity coefficients (API fusion properties were taken from experiments) without any binary interaction parameters fitted to API-polymer experimental data (that is, kij = 0 in all cases). This kind of prediction does not need any experimental binary information and has been underreported in the literature so far, as the routine modeling strategy used in the majority of the existing PC-SAFT applications to ASDs comprised the use of nonzero kij values. The predictive performance of PC-SAFT was systematically and thoroughly evaluated against reliable experimental data for almost 40 API-polymer combinations. We also examined the effect of different sets of PC-SAFT parameters for APIs on compatibility predictions. Quantitatively, the total average error calculated over all systems was approximately 50% in the weight fraction solubility of APIs in polymers, regardless of the specific API parametrization. The magnitude of the error for individual systems was found to vary significantly from one system to another. Interestingly, the poorest results were obtained for systems with self-associating polymers such as poly(vinyl alcohol). Such polymers can form intramolecular hydrogen bonds, which are not accounted for in the PC-SAFT variant routinely applied to ASDs (i.e., that used in this work). However, the qualitative ranking of polymers with respect to their compatibility with a given API was reasonably predicted in many cases. It was also predicted correctly that some polymers always have better compatibility with the APIs than others. Finally, possible future routes to improve the cost-performance ratio of PC-SAFT in terms of parametrization are discussed.