bluuebunny/crossref_metadata_2025 huggingface dataset:
MEMINIMALKAN KESULITAN BELAJAR PESERTA DIDIK DENGAN PENDEKATAN KONSTRUKTIVIS
Authors: Simanullang Dormauli
Published: July 2019

Abstract. This study aims to minimize the difficulty of learning mathematics students by applying learning with a constructivist approach. This classroom action research was conducted on class VIII students of SMP PGRI 3 Banjarmasin, which amounted to 30 people, for 3 cycles. Data collection was done by test and non-test techniques, using learning outcomes tests, observation sheets, and student response questionnaires. Data were analyzed quantitatively and qualitatively. The results showed that (1) student activity in learning increased to 93%; (2) student responses to learning is fun; and (3) student learning completeness increases to 97%. Thus, it can be concluded that mathematics learning with a constructivist approach is able to minimize the difficulty of learning mathematics students on the topic straight line equations. Keywords: constructivist approach, learning difficulties, student activities, straight line equations. Abstrak. Penelitian ini bertujuan untuk meminimalkan kesulitan belajar matematika siswa dengan menerapkan pembelajaran dengan pendekatan konstruktivis. Penelitian tindakan kelas ini dilaksanakan pada siswa kelas VIII SMP PGRI 3 Banjarmasin yang berjumlah 30 orang, selama 3 siklus. Pengumpulan data dilakukan dengan teknik tes dan non tes, menggunakan tes hasil belajar, lembar pengamatan, dan angket respon siswa. Data dianalisis secara deskriptif kuntitatif dan kualitatif. Hasil penelitian menunjukkan bahwa (1) aktivitas siswa dalam pembelajaran meningkat menjadi 93%; (2) respon siswa terhadap pembelajaran adalah menyenangkan; dan (3) ketuntasan belajar siswa meningkat menjadi 97%. Dengan demikian, dapat disimpulkan bahwa pembelajaran matematika dengan pendekatan konstruktivis mampu meminimalkan kesulitan belajar matematika siswa pada topik persamaan garis lurus. Kata kunci: pendekatan konstruktivis, kesulitan belajar, aktivitas siswa, persamaan garis lurus.
PERANCANGAN JARINGAN TRANSMISI MICROWAVE MENGGUNAKAN PASSIVE REPEATER BACK TO BACK DAN DOUBLE FLAT REFLECTOR MENGGUNAKAN PATHLOSS 5.0
Authors: Zuherry Ossa Iqfirlia
Published: July 2019

Menurut Badan Pusat Statistik Indonesia, jumlah penduduk Indonesia sudah mencapai 264 juta. Bertambahnya jumlah penduduk, maka bertambah pula pengguna jaringan telekomunikasi di Indonesia. Seiring dengan bertambahnya jumlah pengguna, maka pelayanan jaringan telekomunikasi juga perlu ditingkatkan. Indonesia sendiri sudah menerapkan beberapa teknologi telekomunikasi dan salah satunya adalah teknologi seluler. Pada teknologi seluler media yang digunakan adalah adalah udara berupa gelombang mikro yang biasa disebut microwave. Teknologi komunikasi radio gelombang mikro digunakan sebagai sarana transmisi antar Base Tranciever Station (BTS) atau Base System Control (BSC). Karena sinyal yang dipancarkan melalui medium udara, maka komunikasi ini rentan terhadap gangguan yang disebabkan oleh perubahan cuaca. Pada keadaan ini dapat diatasi dengan penggunaan passive repater back to back antenna, single reflector dan double flat reflector. Pada tugas akhir ini dilakukan perancangan jaringan microwave menggunakan repeater back to back dan double flat reflector dengan hoplink yang sama. Perancangan jaringan ini microwave dilakukan di Sulawesi Selatan dengan site xBantaeng terletak pada koordinat lintang selatan 05° 29° 07.04° S dan koordinat bujur timur 119° 51° 51.49° E. Sedangkan site xSinjai terletak di koordinat lintang selatan 5° 13° 19.23° S dan koordinat bujur timur 120° 4° 32.27° E, dan koordinat lintang selatan 5° 21° 21.08° S dan koordinat bujur timur 119° 56° 13.83° E digunakan xGunung Sari untuk penempatan repeater dan reflector. Perancangan ini menggunakan Pathloss 5.0. Nilai availability optimalnya bernilai diatas 99%. Untuk kasus pada Tugas Akhir ini baik penggunaan repeater back to back maupun double flat reflector sama-sama mendapatkan nilai optimal. 99,95755% untuk avilability repeater back to back dan 99,82100% untuk double flat reflector. Dengan kesimpulan penggunaan double flat reflector menghasilkan availability yang lebih baik.
Patient-Specific Radiation Dose and Cancer Risk Estimate in Computed Tomography Pulmonary Angiography Examinations Based on Lung Effective Diameter
Authors: Haspi Harun Hanif , Abdul Karim Muhammad Khalis , Abbas Zulkifly , Muniandy Sarawana Chelwan , Sabarudin Akmal , Hoong Ng Kwan
Published: July 2019

Computed Tomography (CT) scan examinations has greater demands especially in CT Pulmonary Angiography (CTPA) owing to the public and radiology personnel worries towards CT radiation exposure and risks. The aim of present study is to evaluate the comprehensive radiation exposure in computed tomography pulmonary angiography (CTPA) and its cancer risk. The records of 100 patients who had undergone CTPA were retrieved. The radiation dose exposure, scanning acquisition protocol as well as patient characteristics were noted. Radiation exposure were presented as Volume Computed Tomography Dose Index (CTDIvol), Size-Specific Dose Estimate (SSDE), Dose-Length Product (DLP), and effective dose (E) and organ dose. Effective cancer risk per million procedure was calculated by referring to the International Commission on Radiological Protection Publication 103. The CTDIvol, SSDE, DLP were comparable within different effective diameter groups. The average effective dose received by a patient was 8.68 mSv. The organ dose and effective cancer risk attained for breast, lung and liver were 17.05 ± 10.40 mGy (194 per one million procedure), 17.55 ± 10.86 mGy (192 per one million procedure) and 15.04 ± 9.75 mGy (53 per one million procedure), respectively. In conclusion, CTDIvol was undervalued and SSDE was more accurate in describing radiation dose exposure. The lungs and breast of subjects with large effective diameter were higher risk of developing cancer as they received the highest exposure. Therefore, extra safety measures should be considered for large-sized patients undergoing CTPA.Purpose: This study evaluates the comprehensive radiation exposure in computed tomography pulmonary angiography (CTPA) and its cancer risk.
Safety and Activity of Metronomic Temozolomide in Second-Line Treatment of Advanced Neuroendocrine Neoplasms
Authors: Tafuto Salvatore , von Arx Claudia , Capozzi Monica , Tatangelo Fabiana , Mura Manuela , Modica Roberta , Barretta Maria Luisa , Di Sarno Antonella , Tornesello Maria Lina , Colao Annamaria , Ottaiano Alessandro
Published: July 2019

Background: The front-line treatment of advanced NeuroEndocrine Neoplasms (NENs) depends on clinical and pathological factors but there are no standard second-line therapies. Methods: Metastatic NENs patients were treated at the ENETS (European NeuroEndocrine Tumor Society) center of excellence of Naples (Italy), from 2014 to 2017 with second-line metronomic temozolomide, 75 mg/m2 per os “one week on/one week off”. Toxicity was graded with NCI-CTC criteria v4.0; objective responses with RECIST v1.1 and performance status (PS) according to ECOG. Results: Twenty-six consecutive patients were treated. Median age was 65.5 years. The predominant primary organs were pancreas and lung. Grading was G2 in 11 patients, G3 in 15. Eleven patients presented with PS 1 and 15 with PS 2. The median time-on-temozolomide therapy was 12.2 months (95% CI: 11.4-19.6). No G3/G4 toxicities were registered. Complete response was obtained in 1 patient, partial response in 4, stable disease in 19 (disease control rate: 92.3%), and progressive disease in 2. The median overall survival from temozolomide start was 28.3 months. PS improved in 73% of patients. Conclusions: Metronomic temozolomide is a safe and active treatment for G2 and G3 NENs. Prospective and larger trials are needed to confirm these results.
Heat Pump Dryer Design Optimization Algorithm
Authors: Andrade Bernardo , Amorim Ighor , Silva Michel , Savosh Larysa , Frölén Ribeiro Luis
Published: July 2019

Drying food involves complex physical atmospheric mechanisms with non-linear relations from the air-food interactions. Moreover, those relations are strongly dependent on the moisture contents and the actual type of food. Such dependence makes it complex to design suitable machines dedicated to a single drying process. To speed-up and streamline the drying machine design, a heat pump dryer design optimization algorithm was developed. The proposed algorithm inputs food and air proprieties, the volume of the drying container and the technical specifications of the heat-pump off-the shelf components. The heat required to dehumidify the food equals the heat exchange process from condenser to evaporator, and the compressor’s requirements (refrigerant mass flow rate and operating pressures) are then calculated. Compressors can then be select based in the volume and type of food to be dried. The algorithm is shown via a flow chart to guide the reader throughout 3 different stages representing each singular physical phenomenon: analysis of the internal air properties; heat flow analysis between components, air and food; food humidity calculus and verification. Results of the application of the algorithm are presented for the drying of Agaricus Blazei mushroom with 3 different humidity contents (60, 80 and 88% of water) for batches of about 45, 123, 200, 277 and 355 kilograms. The results indicate that for the first batch a 610 W compressor will suffice, while for the second one a 990 W compressor will deliver the required work to the refrigerant gas. Further, the last 3 ones would demand for a more potent 1445 W compressor.
MODEL PEMBELAJARAN KETERAMPILAN RENANG GAYA BEBAS (TriAs) UNTUK ANAK USIA SEKOLAH DASAR
Authors: Hidayat Tri Alim Saputra
Published: July 2019

Tujuan penelitian dan pengembangan model keterampilan renang gaya bebas (crawl) untuk anak usia Sekolah Dasar. Selain itu, penelitian dan pengembangan dilakukan untuk memperoleh informasi secara mendalam tentang pengembangan dan penerapan model pembelajaran dan mengetahui efektifitas, efisiensi model yang dibuat. Penelitian dan pengembangan ini menggunakan metode penelitian pengembangan research and development (RnD) dari Borg and Gall. Subjek dalam penelitian dan pengembangan ini adalah siswa Sekolah Dasar kecamatan metro lampung. Uji efektifitas model menggunakan instrumen tes ketermpilan gaya bebas (crawl) untuk mengumpulkan data kemampuan renang siswa Sekolah Dasar. Analisis data penelitian menggunakan uji-t dengan taraf signifikansi 0,05. Analisis data diperoleh nilai rata-rata efektif data keterampilan renang pretest: 44,63 post test: 71,28 dengan nilai signifikansi dari keterampilan yaitu: keterampilan renang gaya bebas dengna t-hitung = -79,88, Df=39 dan P- value = 0,00 < 0,05.  Dengan taraf signifikansi 0,05 maka h0 ditolak. Berdasarkan keterangan tersebut dapat disimpulkan bahwa model pembelajaran keterampilan renang gaya bebas (crawl) untuk usia SD yang dikembangkan dapat diterapkan secara efektif dan eisien sehingga dapat meningkatkan keterampilan renang gaya bebas.
Origin of Micropores In Late Jurassic (Oxfordian) Micrites of the Eastern Paris Basin, France
Authors: Carpentier Cédric , Ferry Serge , Lécuyer Christophe , Strasser André , Géraud Yves , Trouiller Alain
Published: July 2019

Porous micritic facies, either primary chalks or resulting from secondary destructive micritization, can constitute important hydrocarbon or water reservoirs. Characterization of reservoir properties and the understanding of factors which controlled the distribution of porosity are of primary interest to evaluate the prospective reserves. Middle and late Oxfordian limestones of the eastern Paris Basin show several horizons with porosities higher than 20%. The porosity is mainly microporous and located either within secondary micritized grains or in the micritic matrix. Using SEM, cathodoluminescence, as well as confocal microscopy, stable oxygen and carbon isotope ratios, and petrophysical measurements, a scenario for the evolution of the micropores is proposed. Lime mudstones to packstones constitute the majority of the high-porosity facies (HPFs). Inner lagoonal deposits are more micritized and thus more porous than grainstones, and facies rich in leiolitic oncoids and echinoid clasts are less impacted by micritization. Micritization was responsible for an increase of the intragranular porosity in most grain types. During both eogenesis and shallow burial, mineralogical stabilization dissolved aragonitic particles and allowed precipitation of calcite rhombs. This process was probably enhanced below surfaces of subaerial exposure. During burial, Ostwald ripening allowed the growth of larger micrite crystals at the expense of smaller ones during early Berriasian and late Aptian recharges of deep aquifers when the northern margin of the basin was exposed. Overgrowths on micrite crystals were more important in intervals strongly affected by chemical compaction, which favored oversaturation of waters with respect to calcite. In low-porosity horizons (LPFs), the dense micritic texture of oncoids and the monocrystalline architecture of echinoid clasts prevented an intense micritization, while the strong chemical compaction enhanced poronecrosis. Telogenetic fracturing created new fluid pathways that favored inputs of meteoric fluid in porous micrite and allowed the continuation of Ostwald ripening during Cenozoic times. As a whole, mesogenetic inputs of waters undersaturated with respect to calcite in deep aquifers during exposure of basin margins are a more efficient process than early subaerial exposure for enhancing aggrading neomorphism and appearance of microporous micrites. Initial mineralogical heterogeneities also impact the intensity of chemical compaction and thus the stratigraphical distribution of microporous limestones.
Impact of Vegetation On Early Pennsylvanian Fluvial Channels: Insight From the Joggins Formation of Atlantic Canada
Authors: Ielpi Alessandro , Gibling Martin R. , Bashforth Arden R. , Dennar Chinemerem I.
Published: July 2019

Riparian vegetation profoundly influences modern fluvial channels in a variety of ways, depending on the life-history strategies of different plant types, disturbance frequency, and drainage conditions of available habitats. Direct evidence for these dynamic relationships is usually cryptic in ancient deposits. We report evidence for interactions between rivers and in situ vegetation for selected sites in the lower Pennsylvanian Joggins Formation of Atlantic Canada, encompassing fixed, meandering, and distributary channels originally up to 6 m deep. Channel bodies are associated with a suite of fossilized plant remains, specifically lycopsids that preferred stable wetland settings, disturbance-tolerant calamitaleans, and slow-growing, long-lived cordaitaleans.

Vegetation was effective in stabilizing banks and bars and promoting aggradation. Lycopsids and calamitalean groves colonized the channel bed during periods of reduced flow, drawing on the groundwater table, and mounds around upright trunks indicate that they formed bar nuclei after flow resumed. Bank-attached bars with lateral-accretion sets contain upright trees, which may have stabilized inclined sediment surfaces, and trees present between small distributary channels may have formed vegetated islands. Erect lycopsids rooted below the channel base project up into the channel fill, where they formed obstacles and nucleated sediment mounds in active channels. On channel cutbanks, upright lycopsids are tilted towards the channel, and early formed rhizoconcretions are associated with deep cordaitalean root systems in the tops of channel fills. These features imply that vegetation contributed to stabilization of sediment surfaces. The predominance of in situ over transported plant remains suggests that these low-flow-strength rivers had limited ability to erode and entrain large woody debris, especially for small channels with strengthened banks.

We infer that patterns of interaction between vegetation and rivers with a range of fluvial style broadly resembled those of today. By the early Pennsylvanian, rivers had moved from a geomorphic and biogeomorphic mode of operation into a fully ecological mode with prominent feedback loops between vegetation and fluvial processes. Vegetation is commonly poorly preserved in fluvial systems but should be incorporated into facies models for Pennsylvanian and younger strata, possibly also for some Devonian and Mississippian formations.
Basement-involved inversion at the Appalachian structural front, western Newfoundland: an interpretation of seismic reflection data with implications for petroleum prospectivity
Authors: Stockmal Glen S. , Slingsby Art , Waldron John W.F.
Published: July 2019

Recent hydrocarbon exploration in western Newfoundland has resulted in six new wells in the Port au Port Peninsula area. Port au Port No.1, drilled in 1994/95, penetrated the Cambro-Ordovician platform and underlying Grenville basement in the hanging wall of the southeast-dipping Round Head Thrust, terminated in the platform succession in the footwall of this basement-involved inversion structure, and discovered the Garden Hill petroleum pool. The most recent well, Shoal Point K-39, was drilled in 1999 to test a model in which the Round Head Thrust loses reverse displacement to the northeast, eventually becoming a normal fault. This model hinged on an interpretation of a seismic reflection survey acquired in 1996 in Port au Port Bay. This survey is now in the public domain.

In our interpretation of these data, the Round Head Thrust is associated with another basement-involved feature, the northwest-dipping Piccadilly Bay Fault, which is mapped on Port au Port Peninsula. Active as normal faults in the Taconian foreland, both these faults were later inverted during Acadian orogenesis. The present reverse offset on the Piccadilly Bay Fault was previously interpreted as normal offset on the southeast-dipping Round Head Thrust. Our new interpretation is consistent with mapping on Port au Port Peninsula and north of Stephenville, where all basement-involved faults are inverted and display reverse senses of motion. It also explains spatially restricted, enigmatic reflections adjacent to the faults as carbonate conglomerates of the Cape Cormorant Formation or Daniel’s Harbour Member, units associated with inverted thick-skinned faults. The K-39 well, which targeted the footwall of the Round Head Thrust, actually penetrated the hanging wall of the Piccadilly Bay Fault. This distinction is important because the reservoir model invoked for this play involved preferential karstification and subsequent dolomitization in the footwalls of inverted thick-skinned faults. The apparent magnitude of structural inversion across the Piccadilly Bay Fault suggests other possible structural plays to the northeast of K-39.
Hydrothermal dolomitization in the Lower Silurian Sayabec Formation in northern Gaspé – Matapédia (Québec): constraint on timing of porosity and regional significance for hydrocarbon reservoirs
Authors: Lavoie Denis , Morin Claude
Published: July 2019

The study of dolostone of the Lower Silurian Sayabec Formation of the Lac Matapédia syncline, at the western end of the Gaspé Peninsula, sheds new light on porosity development and reservoir potential of the area. The dolomitized section is close to the Shickshock Sud Fault that cuts the southern limb of the syncline. The dolostone occurs either as a highly brecciated unit or as stratiform replacement of peritidal carbonates at the base of the formation. Residual bitumen is seen in the breccia as well as filling of small secondary vugs and fractures within the stratiform dolostone.

The dolostone consists predominantly of replacive matrix dolomite; petrography and oxygen and carbon stable isotope ratios (δ18OVPDB = −6.3 to −7.8‰ and δ13CVPDB = 1.2 to 3.3‰) of the matrix dolomite indicate early burial formation with later recrystallization in the presence of high temperature fluids. Saddle dolomite is found as a pore-filling cement in secondary dissolution pores and fractures. Oxygen stable isotope ratios of the saddle dolomite cement (δ18OVPDB = −14.5 and −15.3‰) indicate precipitation at high temperature. Dull luminescent burial calcite cement follows saddle dolomite. Later dissolution is locally apparent in carbonates as scalloped surfaces covered by finely laminated, bright-very dull luminescent calcites. Petrography and stable isotope ratios of the calcite (δ18OVPDB = −10.1 and −11.2‰ and δ13CVPDB = −2.3 and −6.9‰) suggest precipitation from meteoric waters.

Meteoric dissolution and luminescent-zoned calcite cements are related to a Pridolian sea level lowstand. This event provides a first age constraint on the timing of the hydrothermal dolomitization and hydrocarbon charge of the Sayabec Formation along the northern edge of the Gaspé Belt. The Shickshock Sud Fault channelled the hydrothermal fluids, which dolomitized the Sayabec Formation shortly after initial burial. A recent regional seismic program showed compressive structures (duplexes, backthrust, triangle zone) in the Sayabec Formation inferred to have occurred in latest Silurian–Early Devonian that generated structural traps superimposed on the stratigraphic (shaly facies) and diagenetic (tight non-dolomitized limestone) seals. Seismic anomalies (“flat spots”) in the Lower Silurian section in eastern Quebec suggest the presence of hydrocarbon-filled reservoirs.
Groundwater Vulnerability Mapping in Urbanized Hydrological System Using Modified Drastic Model and Sensitivity Analysis
Authors: Chenini Ismail , Zghibi Adel , Msaddek Mohamed Haythem , Dlala Mahmoud
Published: July 2019

The groundwater vulnerability assessment is normally applied to rural watersheds. However, urbanization modifies the hydrogeological processes. A modified DRASTIC model was adopted to establish a groundwater vulnerability map in an urbanized watershed. The modified DRASTIC model incorporated a land-use map, and net recharge was calculated taking into account the specificity of the urban hydrogeological system. The application of the proposed approach to the Mannouba watershed demonstrates that the groundwater vulnerability indexes range from 80 to 165. The study's results shows that 30 percent of the Mannouba watershed area has a high vulnerability index, 45 percent of the area has a medium index, and 25 percent of the study area has a low vulnerability index. To specify the effect of each DRASTIC factor on the calculated vulnerability index, sensitivity analyses were performed. Land use, topography, and soil media have an important theoretical weight greater than the effective weight. The impact of the vadose zone factor has the most important effective weight and affects the vulnerability index. The sensitivity assessment explored the variation in vulnerability after thematic layer removal. In this analysis, the removal of hydraulic conductivity and impact of vadose zone modified the vulnerability index. Groundwater vulnerability assessment in urbanized watersheds is difficult and has to consider the impact of urbanization in the hydrogeological parameters.
Evaluation of Rockfall-hazard Potential For Rockville, Utah, Following a 2013 Fatal Rockfall
Authors: Jacklitch Carl , Shakoor Abdul , Lund William R.
Published: July 2019

In December 2013, a rockfall in the town of Rockville, Utah, released an estimated 2,700 tons (2,450 tonnes) of rock from a 400-ft (122-m) high slope; the rock struck a house at the base of the slope, resulting in two fatalities. We performed detailed field and laboratory investigations to (1) identify the modes of failure and factors contributing to rockfalls along the east-west trending, south-facing slope where it passes through the town; (2) identify sections of the slope that pose the highest hazard for future property damage or injury; and (3) suggest potential remedial measures. Field investigations included mapping discontinuities, establishing stratigraphy, measuring slope geometry, and evaluating potential failure modes at four selected sites. Laboratory investigations included determining dry density, friction angle, and slake durability index of rock samples. Using the Dips software, we determined the principal joint sets and performed a kinematic analysis. The maximum rollout distances for rock blocks of various sizes were determined for each of the study sites using the RocFall software. Results of the kinematic analysis and field observations indicate that wedge, plane, and toppling failures are possible within the Shinarump Conglomerate Member of the Chinle Formation and the Upper Red Member of the Moenkopi Formation along the entire slope. Based on the results of the study, we developed a rockfall-hazard map that indicates that the western portion of the town faces the highest hazard from potential rockfalls. The most feasible future remedial measure is not to build close to the hazardous slopes. Other possible remedial measures include removing loose rock blocks, installing rock anchors, and using drapery mesh.
Challenging Geostatistical Methods To Represent Heterogeneity in CO2 Reservoirs Under Residual Trapping
Authors: Damico James R. , Ritzi Robert W. , Gershenzon Naum I. , Okwen Roland T.
Published: July 2019

Geostatistical methods based on two-point spatial-bivariate statistics have been used to model heterogeneity within computational studies of the dispersion of contaminants in groundwater reservoirs and the trapping of CO2 in geosequestration reservoirs. The ability of these methods to represent fluvial architecture, commonly occurring in such reservoirs, has been questioned. We challenged a widely used two-point spatial-bivariate statistical method to represent fluvial heterogeneity in the context of representing how reservoir heterogeneity affects residual trapping of CO2 injected for geosequestration. A more rigorous model for fluvial architecture was used as the benchmark in these studies. Both the geostatistically generated model and the benchmark model were interrogated, and metrics for the connectivity of high-permeability preferential flow pathways were quantified. Computational simulations of CO2 injection were performed, and metrics for CO2 dynamics and trapping were quantified. All metrics were similar between the two models. The percentage of high-permeability cells in spanning connected clusters (percolating clusters) was similar because percolation is strongly dependent upon proportions, and the same proportion of higher permeability cross-strata was specified in generating both models. The CO2 plume dynamics and residual trapping metrics were similar because they are largely controlled by the occurrence of percolating clusters. The benchmark model represented more features of the fluvial architecture and, depending on context, representing those features may be quite important, but the simpler geostatistical model was able to adequately represent fluvial reservoir architecture within the context and within the scope of the parameters represented here.
Analysis and Prediction of Gas Recovery from Abandoned Underground Coal Mines in China
Authors: Li Wei , Su Er-Lei , Cheng Yuanping , Zhang Rong , Liu Zhengdong , Younger Paul L. , Pan Dongming
Published: July 2019

Mine closures are likely to become especially widespread in eastern China. However, because of relatively high residual coal-bed methane content, the abandoned coal mine methane (ACMM) reserves of China are huge, and from a greenhouse gas–control perspective it is preferable that they be developed and utilized rather than allowed to vent to the atmosphere. The exploitation and development of ACMM in China is still in its infancy, with theory and practice undergoing rapid development. Four factors are particularly influential in the design of ACMM recovery strategies. The first factor is what may be termed the “enrichment space,” which reflects the final state of the strata after completion of longwall extraction and subsequent strata settlement and is here defined as the region between the outer limit of stress relief and the limit of the extracted panels. Quantitative analysis of the components of gas mixtures recovered from the enrichment space can be tracked using stable carbon isotope techniques. The second factor is the permeability field surrounding the abandoned mine voids. The thick mudstones that commonly overlie the coal seams serve to confine the water and gas within the enrichment space and old mine voids. The geometry of these confining layers can be confirmed by seismic reflection or other geophysical methods, which can reveal the extent of the zone affected by fracture development. On this basis, models of methane movement in abandoned mines can be constrained, allowing valuable predictions of availability of ACMM resources under different mining and post-closure drainage conditions.
Discovering the Polaris Fault, Martis Creek Dam, Truckee, California
Authors: Hunter Lewis E. , Rose Ronn S. , Hilton Bruce , McCormick William , Crampton Todd
Published: July 2019

Martis Creek Dam, located in the Truckee Basin north of Lake Tahoe, CA, was initially rated as one of the U.S. Army Corps of Engineers’ highest risk dams in the United States. While the dam has performed its flood control purpose, a history of excessive seepage during even moderate reservoir levels has prevented it from also fulfilling its potential water storage function. During seepage and seismic studies to assess and mitigate deficiencies, high-resolution light detection and ranging (LiDAR) data were obtained. This imagery provides an unprecedented representation of the ground surface that allows evaluation of geomorphology even in areas with a dense vegetation canopy. At Martis Creek Dam, this geomorphic analysis resulted in the recognition of a previously unknown and through-going lineament between the spillway and dam embankment. This feature extends to the southeast, where several lineament splays are exposed on the East Martis Creek Fan. These lineaments were subsequently explored by paleo-seismic trenching at two locations and confirmed as faults with Late Quaternary to Holocene displacement. Faulting was confirmed in both trenches as unique splays of a fault zone with several feet of apparent normal (vertical) slip and an unknown magnitude, but a potentially significant, strike-slip component. Faulting was observed near the ground surface in both cases, and multiple fault events (a minimum of two) are interpreted as at least latest Pleistocene in age, and probably active in the Holocene.
Continuous Positive Airway Pressure or High Flow Nasal Cannula for Respiratory Distress Syndrome: a Randomized Control Trail among Premature Infants
Authors: Shirvani Tahereh Esmaeilnia , Nayeri Fatemeh Sadat , Shariat Mamak , Nafas Nikoo Nik , Mirjalili Seyyed Reza , Hosseini Seyyed Nasrollah , Sabagh Vafa Ghorban
Published: July 2019

Background
Respiratory distress syndrome (RDS) is a life-threatening pulmonary disorder which mainly related to the premature infants. This study was conducted to evaluate Continuous Positive Airway Pressure (CPAP) and High Flow Nasal Cannula (HFNC) intervention effectiveness among premature infants with RDS.
Methods
Overall, 60 preterm infants with RDS at Valiasr Hospital, Tehran, during 2018 in this randomized control trail participated as CPAP and HFNC groups’ treatment. CPAP group received the nose with a peep of 4-6 centimeters from birth and continued to improve respiratory distress and the need for oxygen (O2). HFNC group received hot and humid flowing 2 to 5 liters/min in nose cannula, until respiratory distress and O2 needing to be resolved. Short clinical outcomes were compared between two groups. Data were analyzed by SPSS version 16 using t-test and logistic regression statistical tests at 95% significant level.
Results
There were no significant differences in Pneumothorax, PDA, chronic lung disease, surfactant injection, tracheal intubation, death, NEC, number of full feeding days, duration of hospitalization, and number of oxygen therapy days between the both CPAP and HFNC groups.
Conclusions
CPAP and HFNC techniques have the same efficacy in confronting RDS in neonates and there is no difference between the two techniques in terms of in-hospital clinical outcomes. However, considering the same efficacy of two methods and less invasive of HFNC compared with CPAP, we concluded this method can be recommended for the improvement of respiratory distress in newborns.
Trial Registration
Iranian Registry of Clinical Trials identifier IRCT20190623043988N1 Registered 2019-07-05.
Trends in Malignant Lacrimal Gland Tumors And Lacrimal Sac Tumors
Authors: Lai Wei-Yu , Lin Yaoh-shiang , Lee Ching-Chih , Yin Chun-Hao
Published: July 2019

Background
Malignant tumors of the lacrimal gland and lacrimal sac are rare entities, and
their incidence has been decreasing. In this study, the incidence trend was examined
in relation to patient demographics of these rare tumors.
Methods
In patient data obtained from the NCI Surveillance Epidemiology and End
Results (SEER) database, International Classification of Diseases for Oncology, third
edition (ICD-O-3) codes for lacrimal gland and lacrimal sac tumors (C69.5) were
used to identify patients with the aforementioned malignancies. Demographic data,
tumor size, treatment, and outcomes were analyzed. Tumor–node–metastasis (TNM)
staging subgroup analysis was conducted for patients who had received AJCC 6th
edition staging at diagnosis. The trend of the incidence rate was calculated per
100,000 person-years by using the joinpoint analysis and age adjusted to the 2000 US
standard population (single ages-census P25-1130). All tests of statistical significance
were two-tailed, and p-value of <0.05 were considered statistically significant.
Results
The trend of lacrimal gland malignancies has decreased significantly over the
years in the white patients. Among the female patients, the incidence rate was
significantly lower in female white patients than in the female nonwhite patients. The
5-year survival rate was relatively higher in the patients with lacrimal gland
malignancies smaller than 2.5 cm (p-value= .007). The female patients with low
socioeconomic status had significantly higher incidence rates (p-value= .041) of lacrimal
sac malignancies than did those with high socioeconomic status.
Conclusions
Lacrimal gland and lacrimal sac malignancies have been decreasing overall in
recent years in the USA. The trend of lacrimal gland malignancies has decreased
significantly over the years in the white patients. Incidence rate vary in gender, race,
and socioeconomic status in lacrimal gland and lacrimal sac malignancies. Analysis of
lacrimal gland and lacrimal sac malignancy trends improved our knowledge of
predisposed populations as well as diagnoses.
Morphologic and functional changes in the retina and sclera induced by form deprivation high myopia in guinea pigs
Authors: zi yingxin , Deng Yu , Zhao Jingru , Ji Meiqi , Qin Yali , Deng Tingting , Jin Ming
Published: July 2019

Background

Our aim was to study the morphologic and functional changes in the retina and sclera induced by form deprivation high myopia (FDHM) in guinea pigs and explore the possible mechanisms FDHM formation.

Methods

Forty 3-weeks-old guinea pigs were randomized into the blank control (Group I, 20 cases) and model groups (20 cases). In the model group, the right eyes of the guinea pigs were sutured 8 weeks to induce FDHM (Group II) and the left eyes were considered a self-control group (Group III). The diopters were measured with retinoscopy. The anterior chamber depth (AC), lens thickness (L), vitreous depth (V) and axial length (AL) were measured using ultrasonometry A. Retinal and scleral morphology and ultrastructural features were observed with light and electron microscopy. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in the retina and sclera were detected with a chemical colorimetric assay.

Results

After remaining stitched for eight weeks, the diopters of Group II changed from (+3.59±0.33) D to (-7.96±0.55) D, and these values were significantly higher than those of Group I (+0.89±0.32) D and Group III (-0.55±0.49) D. The vitreous chamber depth (4.12±0.13) mm and axial length (8.93±0.22) mm of Group II were significantly longer than that of Group I [(3.71±0.23) mm and (7.95±0.37) mm, respectively] and Group III [(3.93±0.04) mm and (8.01±0.15) mm, respectively] (P < 0.05). With the prolongation of form deprivation, the retina and scleral tissue became thinner, the ganglion cell and inner and outer nuclear layers of the retina became decreased, and the arrangement was disordered. In Group II, the activity of SOD was significantly lower than that in Group I and Group III, and the content of MDA was significantly higher in Group II than in Group I and Group III. The differences were statistically significant (P < 0.05).

Conclusions

These findings suggested that in the FDHM guinea pigs model, the diopter, the vitreous chamber depth, and axial length increased significantly with prolongation of monocular FD time, and morphological structural changes in the retina and sclera were observed. Oxygen free radicals might participate in the formation of FDHM.
Serum biomarker CD163 predicts overall survival in patients with pancreatic ductal adenocarcinoma
Authors: Fei Qinglin , Pan Yu , Yu Xingxing , Teng Tianhong , Lin Ronggui , Lin Xianchao , Huang Heguang
Published: July 2019

Background

The serum soluble CD163 (sCD163) is elevated in patients with infection disease and several types of cancer. However, the prognostic value of serum sCD163 in pancreatic ductal adenocarcinoma (PDAC) has not yet been investigated.

Methods

Serum level of sCD163 was measured by using the peripheral blood of 54 patients with PDAC, 20 patients with benign tumor of pancreas, and 30 healthy volunteers (healthy controls). The association between serum sCD163 level and overall survival was analyzed. Receiver operating characteristics (ROCs) curves were generated, and areas under the curve (AUC) were compared to evaluate the diagnostic accuracy, including CA 19-9, CEA, CA 125, CA 153, serum sCD163 level and combination of sCD163 and CA19-9.

Results

Serum sCD163 level of patients with PDAC was significant higher than patients with benign tumor (p = 0.002) and health controls (p < 0.001). Using ROCs curves, we found that the AUC values of serum sCD163 were higher than those of CA 125 and CA 153, but lower than those of CA 19-9 and CEA. The combination of sCD163 and CA19-9 had higher diagnostic accuracy than CA19-9 or sCD163 alone. In addition, the prognosis of PDAC patients with sCD163 ≥ median was worse than sCD163 < median by using univariate analysis (p = 0.027). Further, multivariate analysis showed that higher level of serum sCD163 was still associated with poorer overall survival (p = 0.030). Serum sCD163 was not associated with tumoral CD163 expression, whereas negatively correlated with lymphocyte to monocyte ratio (r = -0.428, p = 0.001).

Conclusion

The serum sCD163 has the potential as a new promising parameter to predict the prognosis in PDAC patients.
A Comparison of Ocular Trauma Scores in a Pediatric Population
Authors: Awidi Abdelhalim , Kraus Courtney L
Published: July 2019

Objective: Pediatric ocular trauma represents a major concern for ophthalmologists. Delays in presentation, incomplete exams, inaccurate visual acuity (VA) results, and amblyopia can limit accurately predicting final visual outcomes in pediatric eye trauma. We performed a retrospective clinical study to describe the demographics and causes of eye trauma. We also compared 2 ocular trauma scoring systems, one specifically designed for pediatric trauma, to classify injuries and determine which better predicted VA outcomes.

A retrospective chart review of 3 years of pediatric globe trauma was performed. Analysis was focused on mechanisms of injury and VA outcomes. Complex factors that may worsen outcomes were recorded. Ocular Trauma Score (OTS) and Pediatric Ocular Trauma Score (POTS) were used to assign Groups 1-5 to each case. Group 1 was poorest prognosis, Group 5 best. Association between Group and final VA was examined. Accuracy of the two systems was compared.

Results: 23 children met eligibility criteria (13 male). Initial VA averaged 20/200 (range no light perception (NLP) – 20/20). Final VA was 20/150 (range NLP - 20/20). Objects of injury were sharp metallic household objects (7), miscellaneous (4), toys (3), BB pellets (2), stick/wood (2), pencil/pen (1).
Hepatitis B virus infection among pregnant women in Bahir Dar, Ethiopia, 2018: An institution based cross sectional study
Authors: Gedefaw Getnet , Waltengus Fikadu , Akililu Almaz , Gelaye Kihinetu
Published: July 2019

Objective: This study aimed to determine the magnitude of serum HBsAg and the risk factors for Hepatitis B virus infection among pregnant women in Bahir Dar. An institution based cross sectional study was implemented from February 1 to May 1, 2018 among 338 pregnant women attending antenatal care clinic at Felegehiwot referral hospital, Bahir Dar, 2018. Systematic sampling technique was implemented. Blood sample was taken from 338 study participants and serum was tested for Hepatitis B surface antigen (HBsAg) using Enzyme Linked Immuno Sorbent Assay.
Results: The overall magnitude of hepatitis B virus infection among pregnant women were 16(4.7%) (95% CI= 2.7, 7.7).Having a history of blood transfusion (AOR=5.2; 95% CI=1.2-22.3), having a history of multiple sexual partners (AOR=4.6; 95% CI=1.1-19.6) and having a history traditional tonsillectomy (AOR=3.4; 95% CI=1.1-10.1) were the major predictor factors for Hepatitis B virus infection.
Keywords: Pregnant women, Bahirdar, Ethiopia, Hepatitis B virus
Supervised training in primary care units but not spontaneous physical activity lowered cardiovascular risk in Brazilian low-income patients: a controlled trial
Authors: Lima Amana M. , Werneck André O. , Cyrino Edilson , Farinatti Paulo
Published: July 2019

Background:

Public health strategies to increase physical activity in low-income communities may reduce cardiovascular risk in these populations. This controlled trial compared the cardiovascular risk estimated by the Framingham Risk Score (FRS) over 12 months in formally active (FA), declared active (DA), and physically inactive (PI) patients attended by the ‘Family Health Strategy’ in low-income communities at Rio de Janeiro City, Brazil (known as ‘favelas’).

Methods:

Patients were matched for age and assigned into three groups: a) FA (supervised training, n=53; 60.5±7.7 yrs); b) DA (self-reported, n=43; 57.0±11.2 yrs); c) PI (n=48; 57.0±10.7 yrs). FA performed twice a week a 50-min exercise circuit including strength and aerobic exercises, complemented with 30-min brisk walking on the third day, whereas DA declared to perform spontaneous physical activity twice a week. Comparisons were adjusted by sex, chronological age, body mass index, and use of anti-hypertensive/statin medications.

Results:

At baseline, groups were similar in regards to body mass, body mass index, triglycerides, and LDL-C, as well to FRS and most of its components (age, blood pressure, hypertension prevalence, smoking, HDL-C, and total cholesterol; P>0.05). However, diabetes prevalence was 10-15% lower in DA vs. FA and PI (P<0.05). Intention-to-treat analysis showed significant reductions after intervention (P<0.05) in FA for total cholesterol (~10%), LDL-C (~15%), triglycerides (~10%), systolic blood pressure (~8%), and diastolic blood pressure (~9%). In DA, only LDL-C decreased (~10%, P < 0.05). Significant increases were found in PI (P<0.05) for total cholesterol (~15%), LDL-C (~12%), triglycerides (~15%), and systolic blood pressure (~5%). FRS lowered 35% in FA (intention-to-treat, P<0.05), remained stable in DA (P>0.05), and increased by 20% in PI (P<0.05). Conclusions: A supervised multi-modal exercise training developed at primary care health units reduced the cardiovascular risk in adults living in very low-income communities. The risk remained stable in patients practicing spontaneous physical activity and increased among individuals who remained physically inactive. These promising results should be considered within public health strategies to prevent cardiovascular disease in communities with limited resources.

Trial registration:

TCTR20181221002 (registered December 21, 2018; retrospectively registered).
The Visitor and Migrant Cost Recovery Programme – A threat to health?
Authors: Potter Jessica Louise , Burman Matthew , Tweed Conor D , Vaghela D , Kunst H , Swinglehurst D , Griffiths CJ
Published: July 2019

Background

In April 2014 the UK government launched the ‘NHS Visitor and Migrant Cost Recovery Programme Implementation Plan’ which set out a series of policy changes to recoup costs from ‘chargeable’ (largely non-UK born) patients. In England, approximately 75% of tuberculosis (TB) cases occur in people born abroad. Delays in TB treatment increase risk of morbidity, mortality and transmission in the community. We investigated whether diagnostic delay has increased since the Cost Recovery Programme (CRP) was introduced.

Methods

There were 3,342 adult TB cases notified on the London TB Register across Barts Health NHS Trust between 1st January 2011 and 31st December 2016. Cases with missing relevant information were excluded. The median time between symptom onset and treatment initiation before and after the CRP was calculated according to birthplace and compared using the Mann Whitney test. Delayed diagnosis was considered greater or equal to median time to treatment for all patients (79 days). Univariable logistic regression was used to manually select exposure variables (p value <0.10) for inclusion in a multivariable model to test the association between diagnostic delay and the implementation of the CRP.

Results

We included 2,237 TB cases. Among non-UK born patients, median time-to-treatment increased from 69 days to 89 days following introduction of CRP (p<0.001). Median time-to-treatment also increased for the UK-born population from 75.5 days to 89.5 days (p=0.307). The multivariable logistic regression model showed non-UK born patients were more likely to have a delay in diagnosis after the CRP (adjOR 1.37, 95% CI 1.13-1.66, p value 0.001)

Conclusion

Since the introduction of the CRP there has been a significant delay for TB treatment among non-UK born patients. Further research exploring the effect of policies restricting access to healthcare for migrants is urgently needed if we wish to eliminate TB nationally.
Untangling the Roots of the West Virginia Opioid Crisis: Relationships in Adolescent Pregnancy, Drug Abuse, and Future Outcomes
Authors: Durr Andrya J. , Critch Elizabeth A. , Fitzgerald M. Paula , Devlin Kelly M. , Fuller Kylie A. , Renzelli-Cain Roberta I
Published: July 2019

Background: The purpose of this study was to determine if there is a relationship between teenage pregnancy and negative health outcomes, including drug abuse, among West Virginia female youth.
Methods: Data was acquired for females between 10 and 19 years of age, by county, from the West Virginia Department of Health and Human Resources. Pearson correlation analysis was utilized to examine the relationship between the teenage pregnancy rate and drug related statistics, pregnancy related statistics, heart health related statistics, and environmental variables. This study was conducted from July 2018 to March 2019 at West Virginia University.
Results: Teenage pregnancy is correlated to harmful behavioral adaptations that may increase a women’s health risks. We find that teenage pregnancy, regardless of pregnancy outcome, is correlated with increased drug overdose death rates for women, as well as health concerns that increase one’s risk for heart disease.
Conclusions: Teenage pregnancy is correlated to a number of outcomes including drug overdose rates and impaired heart health outcomes. Reduction of unintended teenage pregnancy may be useful as a non-traditional method of ameliorating the opioid abuse crisis in the state of West Virginia.