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Philippines is one of the countries in the world known for exporting good quality crops. Mangoes in the Philippines are very popular for its good sweet taste and considerably one of the best. Hence, ensuring the quality of the crop to be exported is essential. The study focused on utilizing convolutional neural network in determining the quality of carabao mango (Mangifera Indica). To make sure that all sides of the mango is going to be considered for the quality assessment, a mechanical system that uses conveyor belt, rollers, and camera was used to gather videos for training and validation of the model. The videos were extracted into frames and gone through image processing to remove the background and retain the mango only. The dataset is composed of different mangoes having both good and bad qualities. The implemented model used a total of 5550 training samples with 94.99% accuracy and a total of 2320 samples used for validation with an accuracy of 97.21%.

It is increasingly recognized that Alzheimer’s disease (AD) exists before dementia is present and that shifts in amyloid beta occur long before clinical symptoms can be detected. Early detection of these molecular changes is a key aspect for the success of interventions aimed at slowing down rates of cognitive decline. Recent evidence indicates that of the two established methods for measuring amyloid, a decrease in cerebrospinal fluid (CSF) amyloid β1−42 (Aβ1−42) may be an earlier indicator of Alzheimer’s disease risk than measures of amyloid obtained from Positron Emission Tomography (PET). However, CSF collection is highly invasive and expensive. In contrast, blood collection is routinely performed, minimally invasive and cheap. In this work, we develop a blood-based signature that can provide a cheap and minimally invasive estimation of an individual’s CSF amyloid status using a machine learning approach. We show that a Random Forest model derived from plasma analytes can accurately predict subjects as having abnormal (low) CSF Aβ1−42 levels indicative of AD risk (0.84 AUC, 0.78 sensitivity, and 0.73 specificity). Refinement of the modeling indicates that only APOEε4 carrier status and four plasma analytes (CGA, Aβ1−42, Eotaxin 3, APOE) are required to achieve a high level of accuracy. Furthermore, we show across an independent validation cohort that individuals with predicted abnormal CSF Aβ1−42 levels transitioned to an AD diagnosis over 120 months significantly faster than those with predicted normal CSF Aβ1−42 levels and that the resulting model also validates reasonably across PET Aβ1−42 status (0.78 AUC). This is the first study to show that a machine learning approach, using plasma protein levels, age and APOEε4 carrier status, is able to predict CSF Aβ1−42 status, the earliest risk indicator for AD, with high accuracy.

Homoleptic fac-IrIIIL3 complexes of 5-aryl-4H-1,2,4-triazole ligands are sky blue emitters. When unsymmetrically substituted, the triazole ligands exhibit atropisomerism, and upon cyclometalation to Ir(III) a mixture of diastereomers is formed. We have isolated and structurally characterized all four possible diastereomers of the fac-IrIIIL3 complex formed upon cyclometalation of an atropisomeric 5-aryl-4H-1,2,4-triazole ligand onto Ir(III). The phosphorescent blue emitting materials reported herein are among the most efficient to date, with quantum efficiencies above 95%.

The variability in grain production makes it necessary to have strategic grain storage plans in order to ensure adequate supplies at all times. However, insects in stored grain products cause infestation and contamination which reduce grain quality and quantity. In order to prevent these problems, early detection and constant monitoring need to be implemented. Acoustic methods have been established in numerous studies as a viable approach for insect detection and monitoring with various sound parameterization and classification techniques. The aim of this study is to further demonstrate the efficacy of acoustic methods in pest management mainly through feature extraction using Mel-frequency cepstral coefficients (MFCCs) and classification using artificial neural network. The study used sounds from the Sitophilus oryzae (L.) or commonly known as rice weevil in larval stage recorded using five different acoustic sensors with the purpose of proving the capability of artificial neural network to recognize insect sounds regardless of the acoustic sensors used. Network models with varying number of nodes for the hidden layer were experimented in search for the highest accuracy that may be obtained. Results show that the network with 25 nodes for the hidden layer provides the best over-all network performance with 94.70% accuracy and the training, validation, and testing are accurate at 95.10%, 94.00%, and 93.60% respectively. Although, difference in accuracy values across all simulations never exceeded 1%. These show that the proposed method is capable of recognizing insect sounds regardless of the acoustic sensors used provided that proper acoustic signal preprocessing, feature extraction, and implementation of the network are performed.

Ir(III) complexes of cyclometalated 5-aryl-1H-1,2,4-triazole ligands are highly efficient, phosphorescent emitters. We describe herein a series of fac-IrL3 complexes, in which the nature of aryl substituents are shown to strongly affect emission wavelength over the range 453–499 nm. Computational and structural studies indicate that for aryl groups the point of attachment and dihedral angle with respect to the cyclometalated ring influence emission color. Significantly, this degree of color tuning may be achieved without resorting to electron-withdrawing or -donating groups. Photo- and electroluminescence device studies of the different emitters indicate that they are generally highly efficient: photoluminescent efficiencies >90% and external quantum efficiencies of up to 22% are observed.

Polyoligosilsesquioxanes (POSS) are a large family of Si–O cage molecules that have diameters of 1–2 nm and can be viewed as perfectly monodisperse silica nanoparticles. POSS can be synthesized wit...

Philippines is one of the world’s leading exporter of mangoes. The country produces many varieties of mangoes, one of which is the ‘Carabao’ mango. Several metric tons of mangoes are produced, and these have to be checked for defects before entering the market. With recent advances in technology, it has become efficient and relatively easy to use for these applications. The objective of this paper is to present a non-destructive method to check the quality of mangoes using computer vision (CV) and convolutional neural network (CNN) with a minimal number of samples. An experimental setup was created to simulate a production line. A webcam was used for capturing images of the mangoes, while a mini computer was used for controlling the peripherals. As basis for categorizing the mangoes as either good or bad, the Philippine National Standard (PNS) for mangoes was used. A basic background subtraction algorithm was used to extract the mango’s image. With these extracted images, a 2-category network was trained, and the achieved classification accuracy was 97.21%. The goal of having a high accuracy in classifying mangoes was achieved. There are multiple paths to explore in the future, including additional feature extraction methods, different neural networks, and hardware improvements, in order to speed up the sorting process. Moreover, it may be necessary to be able to identify mangoes with only slight defects to be used for other products, such as dried mangoes, to reduce product wastage.

Ir(III) complexes are efficient phosphorescent emitters. The transition dipole moment between the triplet and singlet manifolds is formally spin forbidden. However, spin–orbit coupling (SOC), induced by the high angular momentum orbitals in Ir, efficiently mixes the triplet manifold with higher-energy singlets, increasing the transition probability. Spin–orbit coupled time-dependent density functional (TDDFT) calculations within the zero-order relativistic approximation (ZORA) are used to study nine complexes that have a range of emissions from 450 to 630 nm and quantum efficiencies of 0.1–0.9. We find that using the singlet ground-state geometry to calculate radiative rates produces the best correlation with experiment. We also show that the equal thermal population of the three sublevels in the triplet manifold is sufficient to understand rates at 300 K. We find that emission energies and radiative rates are best reproduced at the TD-B3LYP/TZP/DZP//BP86/TZ2P/TZP level of theory, where the larger basis s...

In Philippines, there is a big problem in parking because of the highly increasing number of vehicles which has a big impact in the commuters, this lead the creation of Real-Time Viewing Automated Parking System that help the parking congestion especially in mall parking and other establishment. The system uses proximity sensors for the prototype to detect the vehicles. The driver can use mobile phone to access the web application and reserve the slot for parking while the system administrator assist the transaction. This parking system can lessen the struggling on finding parking availability and tool for transportation trends.

Linear perfluorinated aldehydes (PFALs, CnF2n+1CHO) are important intermediate species in the atmospheric oxidation pathway of many polyfluorinated compounds. PFALs can be further oxidized in the gas phase to give perfluorinated carboxylic acids (PFCAs, CnF2n+1C(O)OH, n ) 6, 12) which have been detected in animal tissues and at low parts per billion levels in human blood sera. In this paper, we report ab initio quantum chemistry calculations of the decarbonylation kinetics of C nF2n+1CO radicals. Our results show that CnF2n+1CO radicals have a strong tendency to decompose to give CnF2n+1 and CO under atmospheric conditions: the Arrhenius activation energies for decarbonylation of CF3CO, C2F5CO, and C3F7CO obtained using PMP4/ 6-311++G(2d,p) are 8.8, 6.6, and 5.8 kcal/mol, respectively, each of which is about 5 kcal/mol lower than the barrier for the corresponding nonfluorinated radicals. The lowering of the barrier for decarbonylation of CnF2n+1CO relative to that of CnH2n+1CO is well explained by electron withdrawal by F atoms that serve to weaken the critical C-CO bond. These results have important implications for the atmospheric fate of PFALs and the atmospheric pathways to PFCAs. The main effect of decarbonylation of CnF2n+1CO is to decrease the molar yield of CnF2n+1C(O)OH; if 100% of the CnF2n+1CO decompose, the yield of CnF2n+1C(O)OH must be zero. There is considerable scope for additional experimental and theoretical studies.

The mode of action of many pest or disease control agents involves inhibition of some metalloenzyme that is essential for the survival of the target organism. These inhibitors typically consist of a functional group that is capable of a primary binding interaction with the metal and a scaffold that is capable of secondary interactions with the remainder of the enzyme. To characterize the binding ability of various metal binding groups (BGs), we have performed electronic structure calculations on ligand displacement reactions in a model system related to the metalloenzyme, peptide deformylase: E-M-R + BG → E-M-BG + R. Here E represents a model coordination environment for the metal M, and R is a reference ligand (e.g., water) that may be displaced by a metal binding group. Since the oxidation state of many of the metals considered allows for multiple spin states, we also studied the influence of spin state on the coordination environment. Qualitative considerations of electronic structure inspired by the calculations provide an understanding of binding energy trends across a variety of ligands for a given metal and across a variety of metals for a given ligand.

Density functional theory methods were used to investigate the structures associated with 2-phenylpyridine, ppy, and several of its electronic states. The structure of ppy has the aromatic rings twisted with respect to one another by ∼21°, which is about half the value found for biphenyl. In comparison with ppy, both the isoelectronic cation, ppyH(+), and anion, ppy(-), have larger twist angles. The extent of twisting is governed by the delicate balance between π conjugation and repulsive orbital/steric interactions, and the magnitudes of these interactions were investigated by examining the torsional energy barriers for all three molecular species. In contrast, every one of the investigated open-shell structures [Formula: see text] ppy(•)(+), ppy(•)(-), ppy*, ppyH(+)*, and ppy(-)* [Formula: see text] has coplanar aromatic rings, that is, no twist angle. Frontier molecular orbital analyses reveal that the π-type bonding between the bridging carbons becomes dominant over any repulsive orbital and steric interactions, thereby leading to coplanar rings. Also, the energetics associated with ppy and its various electronic states were investigated and reported.

The first experimental evidence is presented for planar–bent isomerism of complexes of the type [L4M2(μ-X)2]. Both the planar and bent forms have been detected for the same composition, [(Ph3P)4Rh2(μ-F)2], with full exclusion of any variation in such factors as the nature of the metal, ligand, counterion, and solvent of co-crystallization. Computationalstudies point to weak C–H···F intramolecular bonding as an additional factor affecting the choice between the planar and bent geometries. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

In its continuing quest for smaller length scales, the electronics industry plans to introduce 157 nm as the next lithographic wavelength. Accordingly, there is a pressing need to develop photoresists that are more transparent, and pellicles that are both more transparent and more durable. With the advent and popularization of time-dependent density functional theory (TD-DFT), we now have a practical quantum chemical method for calculating excitation energies and transition moments in the vacuum ultraviolet (VUV) which can greatly assist in the scouting of highly transparent materials. We have performed TD-DFT calculations for a broad variety of fluorinated molecules and we will report calculated VUV photoabsorption spectra for a large family of model fluorohexanes. These calculations, which span a range from 1-fluorohexane to CH 3 CF 2 CF 2 CF 2 CF 2 CH 3 , illustrate some of the principles one may use to design low absorption polymeric materials.

The origin of two minor but enigmatic side bands in the Fourier-transform infrared spectrum (FTIR) of acetone oxime vinyl ether is resolved with density functional theory calculations. A comparison of vibrational frequencies as computed with Hartree–Fock self-consistent-field theory and density functional theory is carried out for acetone oxime vinyl ether, and N-(3-nitrobenzylidene)-p-phenylenediamine. Implications for molecular electronics are discussed.

Hydrofluorocarbons (HFCs), such as HFC-134a (CF3CFH2), are replacing chlorofluorocarbons (CFCs) in many applications because of their low ozone depletion potentials. The more complex chemical syntheses of HFCs, however, may not provide the molecular species desired with sufficient purity, leading to the need to separate reaction products. An important example is provided by the separation of the isomers HFC-134a and HFC-134 (CF2HCF2H) over the faujisitic zeolite NaX (Na86Al86Si106O384). An understanding of the fundamental mechanism controlling this separation involves the unusual aspect that HFC-134 can exist as either a trans or gauche conformer; a key factor is that the trans conformer is nonpolar whereas the gauche conformer is highly polar. Here we report the results of a Raman scattering study which show the trans-gauche population ratio for HFC-134 adsorbed on NaX is decreased as much as 20-fold compared to the gas phase. Furthermore, the conformational ratio changes with HFC loading, the polar gauc...