Effect of Anisotropic Brain Conductivity on Patient-specific Volume of Tissue Activation in Deep Brain Stimulation for Parkinson Disease

Objective: Deep brain stimulation (DBS) modeling can improve surgical targeting by quantifying the spatial extent of stimulation relative to subcortical structures of interest. A certain degree of model complexity is required to obtain accurate predictions, particularly complexity regarding electrical properties of the tissue around DBS electrodes. In this study, the effect of anisotropy on the volume of tissue activation (VTA) was evaluated in an individualized manner. Methods: Tissue activation models incorporating patient-specific tissue conductivity were built for 40 Parkinson disease patients who had received bilateral subthalamic nucleus (STN) DBS. To assess the impact of local changes in tissue anisotropy, one VTA was computed at each electrode contact using identical stimulation parameters. For comparison, VTAs were also computed assuming isotropic tissue conductivity. Stimulation location was considered by classifying the anisotropic VTAs relative to the STN. VTAs were characterized based on volume, spread in three directions, sphericity, and Dice coefficient. Results: Incorporating anisotropy generated significantly larger and less spherical VTAs overall. However, its effect on VTA size and shape was variable and more nuanced at the individual patient and implantation levels. Dorsal VTAs had significantly higher sphericity than ventral VTAs, suggesting more isotropic behavior. Contrastingly, lateral and posterior VTAs had significantly larger and smaller lateral-medial spreads, respectively. Volume and spread correlated negatively with sphericity. Conclusion: The influence of anisotropy on VTA predictions is important to consider, and varies across patients and stimulation location. Significance: This study highlights the importance of considering individualized factors in DBS modeling to accurately characterize the VT

Technical-Vocational Livelihood Education: Emerging Trends in Contextualised Mathematics Teaching

Technical-Vocational Livelihood Education (TVLE) Strategies and Indicators (S&Is) are the strategic procedures needed to come up with a well-informed contextualised learning instruction. This study is aimed at exploring the trends in Technical-Vocational Livelihood Education. The focus of this study is on soliciting relevant strategies and indicators (S&I) that can be utilised to develop a contextualised mathematics teaching module. S&Is in this study are consolidated from various experts in the field of curriculum contextualisation who were purposively selected from various regions representing the DepEd Manila, DepEd Mindoro, Marinduque, Romblon, and Palawan (MIMAROPA), DepEd Bicol region (Region 5), and DepEd Central Visayas (Region 7) recommended by the Department of Education (DepEd) Manila. Formal interviews and coding of consolidated experts’ experiences have passed through a qualitative thematic analysis to obtain a profound understanding of the strategies and indicators. After a thorough investigation of the information gathered, related studies, and theoretical reviews, the study resulted in the seven (7) stages of a contextualised mathematics teaching module such as 1) Planning, 2) Assessment of the curriculum guide and resources, 3) Collaboration and Consultative Meeting, 4) Crafting and Developing of the Contextualise Learning Modules/Lessons, 5) Implementation, 6) Monitoring, and 7) Evaluation and feedback. The first four (4) stages are the developmental phase cons Planning, Assessment, Collaboration, and Crafting of the working module (PACC). While, the remaining three stages to implement, monitor, and conducts of evaluation and feedback are on the validation phase. As module, the contextualised mathematics teaching can be utilised as a training guide for teachers in Technical-Vocational Livelihood Education strands of the K-12 curriculum. Further research may be conducted to validate the most appropriate modular approach in teaching specific subjects

Adakitic Paracale Granodiorite in southeastern Luzon, Philippines: A peek at a Proto-Philippine Sea Plate-related magmatic arc

This paper describes the geochemistry, petrogenesis and tectonic setting of a silicic pluton, the Paracale Granodiorite (PG), intruded into an ophiolitic suite in southeastern Luzon island, Philippines. Whole rock chemistry suggests that the PG samples are calc-alkaline and are characterized by light rare earth element (LREE)-enrichment and relatively weak heavy rare earth element (HREE)-depletion. They also show depletion in Nb, Ta, Zr and Ti and positive anomalies in K, Pb and Sr when normalized with the Primordial Mantle and normal-mid-ocean ridge basalt (N-MORB). The PG biotite mineral chemistry shows an affinity to calc-alkaline trends based on the FeOtot versus Al2O3, whereas in the MgO-Al2O3 plot, they exhibit transitional calc-alkaline to peraluminous characteristics. These information, along with a temperature \u3e600 °C based on biotite chemistry, and hydrous setting for the generation of the PG suggest generation in a subduction-related setting. When plotted in the Y versus Sr/Y and YbN versus (La/Yb)N, the PG samples exhibit adakitic signature. Partial melting, fluid addition and sediment participation are discerned from the geochemistry. Melting, assimilation, storage and homogenization (MASH) with limited fractionation are the dominant mechanisms of formation. The PG could represent a Late Cretaceous to Paleogene magmatic arc generated during the subduction of the proto-Philippine Sea Plate

Professional Track Technology Postgraduate Education: A Tracer Study

The Graduate Education programs at the schools are vital for the future workplace. The fact that graduates can overcome obstacles and complete the program requirements fills them with privilege, gratitude, pride, and happiness. An established tracer's research developed to determine students' current conditions, even though Commission on Higher Education (CHED) compels Higher Education Institutions (HEIs) to monitor students' career pathways and whereabouts. Fifty-two respondents participated in the feedback process using the snowball and quota sampling approaches, and the questionnaire completed validity and reliability testing. Also, the targeted demographics are meant to generate results and act as the cornerstone for ideas or cooperative solutions

Consumed tectonic plates in Southeast Asia: Markers from the Mesozoic to early Cenozoic stratigraphic units in the northern and central Philippines

Tectonic reconstruction models of Southeast Asia all invoke in the early Cenozoic the collision of Mesozoic oceanic plates, which have been fragmented, consumed along subduction zones or emplaced onto the overriding plate. However, with marked variations in these models, we reinvestigate the tectonic evolutionary landscape of Southeast Asia through the lens of Philippine geology. In particular, we present revisions to the more recent models by adopting the unique approach of integrating data that we have gathered for the past 17 years from the Upper Mesozoic to Lower Cenozoic stratigraphic formations in northern and central Philippines. These formations, which resulted mainly from submarine mass transport processes, evolved in response to early arc-related processes of oblique subduction, frontal wedge deformation, terrane accretion and strike slip faulting. Additional key constraints for the revisions include: (1) the timing of early Cenozoic magmatism in eastern Luzon; (2) the spatial distribution of the Upper Mesozoic to Lower Cenozoic sedimentary formations with respect to other key features (e.g. distribution of Mesozoic ophiolite fragment and continent-derived rocks) in the Philippine arc; (3) the paleolatitudinal position of Luzon and surrounding regions and; (4) the movement of the surrounding plates since the Late Mesozoic. In revising previous models, a subduction zone (proto-East Luzon Trough) separating Benham Plateau and the Philippine arc was placed to explain the spatial distribution of Eocene arc-related formational units and Mesozoic ophiolite materials comprising the accretionary complex east of Luzon at ~40 Ma period. During this time, Luzon was modeled at the southern margin of the East Asia Sea or the proto-Philippine Sea Plate. Mesozoic ophiolitic complexes that line the eastern Philippine arc as well as the ophiolitic and pelagic limestone and chert fragments included in the arc-derived, Eocene formations in Luzon could very well be traces of the now consumed East Asia Sea-proto-Philippine Sea Plate. Within the same period, we modified the Palawan Microcontinental Block (PCB), positioned at the trailing edge of the proto-South China Sea to include the whole Mindoro island and the Romblon Island Group in Central Philippines. Pieces of the consumed Izanagi Plate, the proto-South China Sea and continental-derived sediments from Asia mainland are reflected in the Mesozoic metamorphic rocks and the Eocene sedimentary formation in western Mindoro. Finally, we model Cebu, Bohol and Negros islands in Central Philippines as being at the leading oceanic edge of the Indo-Australian Plate during the early Cenozoic. With the northward movement of the Indo-Australian plate and the trench roll back of the southern margins of the Philippine Sea Plate, the accretion of the Cretaceous arc-related rocks of Cebu, Bohol and Negros onto the Philippine arc by the end of Eocene or early Oligocene becomes a possibility

Renal cell carcinoma: associations between tumor imaging features and epidemiological risk factors

Purpose: To investigate associations between imaging features of tumors and age, gender and body mass index (BMI) in patients with renal cell carcinoma. Method: This IRB-approved, HIPAA-compliant study included 1348 patients with histopathologically confirmed renal cell carcinoma of the clear cell subtype (ccRCC, n = 904) or non-clear cell subtype (n = 444), who underwent pre-treatment CT imaging less than 180 days before nephrectomy between 1999 and 2011. Two radiologists independently, retrospectively analyzed all imaging studies and identified features (necrosis, renal vein invasion, contact with renal sinus fat, multicystic appearance and nodular enhancement), which were then correlated with patient age, gender and BMI at time of surgery. Results: Inter-reader agreement on imaging features ranged from substantial to excellent (kappa: 0.688 to 0.982). In the ccRCC group, multicystic tumor appearance was significantly associated with lower patient age (p < 0.05) and lower BMI (p < 0.05); the presence of renal vein invasion was significantly associated with lower BMI in males (p < 0.05); and both tumor contact with the renal sinus and nodular enhancement were significantly associated with greater patient age (p < 0.05). In the non-clear cell RCC group, necrosis was associated with lower BMI for females (p < 0.05). Conclusions: This study demonstrated significant associations between imaging features of RCC and patient age and BMI, hinting an influence of these factors on tumor biology and genomic make-up. These findings could aid future studies in selecting patients while investigating genomic, molecular and metabolic variables in RCC and might potentially impact on future stratification and therapy of patients

Charge gap in the one--dimensional dimerized Hubbard model at quarter-filling

We propose a quantitative estimate of the charge gap that opens in the one-dimensional dimerized Hubbard model at quarter-filling due to dimerization, which makes the system effectively half--filled, and to repulsion, which induces umklapp scattering processes. Our estimate is expected to be valid for any value of the repulsion and of the parameter describing the dimerization. It is based on analytical results obtained in various limits (weak coupling, strong coupling, large dimerization) and on numerical results obtained by exact diagonalization of small clusters. We consider two models of dimerization: alternating hopping integrals and alternating on--site energies. The former should be appropriate for the Bechgaard salts, the latter for compounds where the stacks are made of alternating $TMTSF$ and $TMTTF$ molecules. % $(TMTSF)_2 X$ and $(TMTTF)_2 X$ ($X$ denotes $ClO_4$, $PF_6$, $Br$...).Comment: 33 pages, RevTeX 3.0, figures on reques

Geochemistry of the Late Cretaceous Pandan Formation in Cebu Island, Central Philippines: Sediment Contributions From the Australian Plate Margin During the Mesozoic

The Late Cretaceous Pandan Formation in Cebu Island is one of the oldest sedimentary units in the Central Philippines. The inconsistencies in geological descriptions and interpretation of the depositional environment of the Pandan Formation complicated efforts to determine the origin and tectonic history of the basement of Cebu Island. This study therefore looks into the petrological and geochemical characteristics of the Pandan Formation and their implications for the tectonic development of the Philippine Arc during the late Mesozoic. Petrographic analyses indicate significant contribution from mafic sources with additional inputs from felsic rocks, siliciclastics and metamorphic sources. Enrichment of detrital quartz from felsic volcanic and plutonic rocks, as well as from siliciclastic and metamorphic sources, has shifted the SiO2 composition of the Pandan clastics from a mafic to a more intermediate source. Whole-rock geochemical analyses revealed low SiO2/Al2O3 = 4.21, low K2O/Na2O = 1.16, low Th/Sc = 0.13, low Th/U = 2.78, high La/Th = 4.51, significantly low REEs = ca 76.45 ppm and low LaN/YbN = 4.28. A slight negative chondrite-normalized Eu/Eu* (0.91) anomaly and significantly high PAAS-normalized positive Eu/Eu* (1.39) values are consistent with derivation from a young undissected magmatic arc terrane. Tectonic discrimination diagrams suggest formation in an oceanic island arc to active margin/collision zone modelled to be located at the oceanic leading edge of Australia. Rapid uplift and erosion of the magmatic arc and older allochthonous blocks gave way to the rapid deposition of the Pandan Formation in the Late Cretaceous at the subequatorial region

Corrosion Inhibition of Sodium Silicate with Nanosilica as Coating in Pre-Corroded Steel

This study was conducted to investigate the potential of using sodium silicate with nanosilica as a treatment to inhibit the progress of corrosion in steel specimens that are already corroded. Steel specimens measuring 16 mm in diameter and 4 mm in thickness were prepared and subjected to pre-corrosion by immersion to 3.5% NaCl solution. Two sets of specimens were then dip-coated with sodium silicate containing nanosilica. One set was coated with 1% nanosilica, and the other was coated with 2.5% nanosilica. The coated specimens were then subjected to Complex Impedance Spectroscopy (CIS) at 20 Hz to 20 MHz frequency range. Compared with the sodium silicate coating with 1% nanosilica, the sodium silicate coating with 2.5% nanosilica had a larger semi-circle curve in the Nyquist plot. Similarly, the sodium silicate coating with 2.5% nanosilica also showed larger magnitudes of impedance at the low-frequency region and larger phase angles at the high-frequency regions in the Bode plot. These results imply that the sodium silicate coating with 2.5% nanosilica coating demonstrated better capacitive behavior. In addition, equivalent circuit modelling results also showed that the sodium silicate coating with 2.5% nanosilica had higher coating resistance and lower coating capacitance as compared to the sodium silicate coating with 1% nanosilica. Doi: 10.28991/cej-2021-03091761 Full Text: PD

Epithermal Mineralization of the Bonanza-Sandy Vein System, Masara Gold District, Mindanao, Philippines

The Masara Gold District in southeastern Mindanao island is an area of prolific hydrothermal copper and gold mineralization. This study documents the mineralization characteristics of the NW-trending Bonanza-Sandy epithermal veins to constrain possible hydrothermal fluid sources and ore-forming mechanisms. Epithermal mineralization in the NW veins is divided into three main stages: Stage 1 - massive quartz-sulfide; Stage 2 - massive to amorphous quartz-carbonate (calcite); and Stage 3 - colloform-cockade quartz-carbonate (bladed rhodochrosite). Stage 1 is the main gold mineralization phase, with chalcopyrite, pyrite, sphalerite and galena occurring with native gold and tellurides. Stages 2 and 3 contain invisible gold in the sphalerite, galena, pyrite and chalcopyrite. The deposit exhibits mineralization characteristics typical of intermediate sulfidation epithermal deposits based on the dominant chalcopyrite-pyrite mineral assemblage; illite-muscovite-chlorite alteration mineralogy that point to neutral pH conditions; and sphalerite composition of 2.26 to 8.72 mol% FeS in Stage 1 and 0.55 to 1.13 mol% FeS in Stage 2. The K-Ar age date of illite separates from highly altered diorite porphyry of the Lamingag Intrusive Complex yielded an Early Pliocene age (5.12 ± 0.16 Ma). Hydrothermal fluid exsolved from the magma that formed the Lamingag Intrusive Complex probably formed the ore-forming Stage 1 veins. Stages 2 and 3 involved the deposition of quartz and carbonate veins possibly by boiling hydrothermal fluids. Precious and base metal deposition was controlled by the Masara Fault Zone. Exploration markers for gold mineralization in the Masara Gold District and vicinity include the presence of Lamingag Intrusive Complex and massive sulfide veins