bluuebunny/crossref_metadata_2025 huggingface dataset:
Transtorno dissociativo de identidade
Authors: Cotrik Ervin Michelstaedter , Dourado Junior Jose Brasileiro , Repsold Paulo Roberto
Published: September 2023

O transtorno dissociativo de identidade, anteriormente conhecido como transtorno de personalidade múltipla, caracteriza-se pela alternância de duas ou mais personalidades no controle da mesma pessoa. A pessoa que apresenta duas ou mais identidades possui falhas em suas memórias sobre eventos rotineiros, informações pessoais importantes e eventos traumáticos ou estressantes, bem como vários outros sintomas, incluindo depressão e ansiedade. Este transtorno de personalidade pode ser desenvolvido após estresse ou um trauma devastador durante a infância. Como é feito o diagnóstico diferencial? Com a presença destes lapsos de memória característicos da doença, como é feito o tratamento?
Especial setembro amarelo
Authors: Silva Antônio Geraldo da , Gorender Miriam Elza , Martins Claudio Meneghello , Minervino Alfredo José , Baldaçara Leonardo Rodrigo
Published: September 2023

Há 10 anos, o presidente da Associação Brasileira de Psiquiatria, Dr. Antônio Geraldo da Silva, inseriu no calendário nacional a Campanha Setembro Amarelo. Desde 2014, o Conselho Federal de Medicina se tornou nosso parceiro e nos ajuda nessa empreitada em busca de diminuir os altos índices de suicídio em nosso país. Ao longo dos anos nossa campanha foi acolhida por diversos pontos turísticos do Brasil, como o Elevador Lacerda em Salvador, a Catedral do Distrito Federal, Catedral de Santo Antônio de Pádua em Minas Gerais, a Arena das Dunas no Rio Grande do Norte, a Basílica de Nossa Senhora da Penha e os Arcos da Lapa no Rio de Janeiro, o Teatro Amazonas. Faça como milhões de pessoas e nos ajude a disseminar cada vez mais nossa campanha, acesse www.setembroamarelo.com e distribua nossos materiais, leia nossas cartilhas e se informe sobre o assunto, seja ativo no Setembro Amarelo e nos ajude a salvar vidas!
Comparison of Corcos-Based and Experimentally Derived Coherence Factors for Buffet Forcing Functions
Authors: Soranna Francesco , Heaney Patrick S. , Sekula Martin K. , Piatak David J. , Ramey James M.
Published: September 2023

In this paper, high-spatial-resolution unsteady pressure-sensitive paint (UPSP) data are utilized to compare two methods for panel buffet forcing function (BFF) estimation for the Space Launch System (SLS). Such methods are based on discrete pressure measurements within a panel but employ coherence factors to account for partially correlated fluctuating pressures across the whole panel. In one method, coherence factors are derived based on the Corcos model, whereas the second method utilizes experimentally derived coherence factors. To simulate discrete measurements using UPSP data, suitable subsets of the data are extracted. When full UPSP resolution is retained, UPSP data provide a benchmark to assess discrete-measurement-based methods. The analysis focuses on the peak SLS buffet environment located downstream of the forward attachment hardware (FAH) between the core stage and solid rocket boosters. Trends of the Corcos-based and experimentally derived coherence factors are in reasonable agreement with the benchmark. However, at certain frequencies, experimentally derived coherence factors are sensitive to the separation distance between pressure measurements utilized to compute coherence lengths. Such sensitivity originates from deviation of the experimentally based coherence function from an exponential decay assumption. On the other hand, the present implementation of the Corcos model fails to capture certain nonturbulent boundary-layer-related environments, such as a subharmonic of FAH vortex shedding. For all methods presented in this paper, at near-transonic conditions, increased pressure coherence and spatial nonuniformity lead to BFF overestimation and sensitivity to the pressure measurement location within the panel.
Mission Profile Analysis of Point-to-Point Rocket Cargo Transportation System Using Trajectory Optimization
Authors: Lee Sang-Don , Jung Ki-Wook , Lee Chang-Hun
Published: September 2023

This paper proposes new concepts for the point-to-point rocket cargo transportation system (RCTS). The RCTS is a transportation system that can deliver cargo anywhere on Earth in an hour using reusable launch vehicle technologies. As a fundamental study of global transportation on Earth, we especially address the mission profiles for short-range transportation within hundreds of kilometers using small rocket engines, which are intended for logistics transportation within neighboring countries or domestic transportation in a country. Two mission profiles of the RCTS are introduced, and the flight phases of each concept are explained in detail. The trajectory optimization problem of the RCTS is formulated based on the mission profiles, incorporating the flight constraints, boundary conditions, and an objective function that aims to maximize the payload ratio. The explicit-guidance is employed during the landing burn phase to enhance the convergence of the optimization problem by expanding the feasible region. The coevolutionary augmented Lagrangian method, one of the evolutionary algorithms, is utilized to obtain the solution for the trajectory optimization problem. The optimal trajectory and state variables are presented through numerical simulations. Additionally, parametric studies are performed to determine the payload mass trend of the RCTS. The trajectory optimization results are summarized to provide an analysis and comparison of the proposed mission profiles.
Rheological, Ballistic, and Mechanical Properties of 3D Printed, Photocured Composite Propellants
Authors: Lajoie Justin , Blocker Jacob , Sippel Travis
Published: September 2023

This study explores the rheological, mechanical, and ballistic properties of printed ammonium perchlorate composite propellant at 82.5% solids loading with binders curable with ultraviolet light of wavelength from 215 to 400 nm (UV). A polybutadiene urethane acrylate and two polyester urethane acrylate propellants are printed by an in-house-fabricated fused deposition molding printer. Propellants are all shear-thinning and have significantly lower viscosity than similar hydroxyl-terminated polybutadiene (HTPB) propellants. Uniaxial stress–strain measurements indicate that ultimate tensile strength and ultimate tensile strain of all photocurable propellants are found to be greater than HTPB propellant. In particular, the ultimate tensile strain of polyester urethane acrylate propellant is six times that of HTPB propellant, demonstrating high compliance. Ballistic properties are measured from combustion of printed propellant articles in a windowed Crawford combustion bomb at inert gas pressures of up to 12.1 MPa. The burning characteristics were found to be relatively planar, though strong burning rate anisotropy, expected as a result of print layer inhomogeneities, was observed in two of the three formulations. Overall, pressure exponents of the propellants were mild and ranged from 0.17 to 0.33. These results are compared and contrasted to those of other printed propellants. These results provide valuable insight into the selection of a safe binder system for printing of photocurable composite propellants.
Uncertainty in Modeling Ablation Heat Transfer in Rocket Nozzles
Authors: Heath Bradley , Ewing Mark
Published: September 2023

The ablation of carbon cloth phenolic insulators used in solid rocket motor (SRM) nozzles involves highly complex phenomena that are difficult to accurately predict. Historical and even more modern ablation predictions rely heavily on anchoring to SRM test data to improve predictability and SRM reliability. Accelerated schedules, reductions in static SRM testing prior to flight, and a highly competitive global market are placing a substantial onus on computational capability and predictive uncertainty. Quantifying uncertainty in SRM nozzle ablation predictions is essential for motor reliability. This paper provides the details of a modern uncertainty quantification methodology applied to ablation predictions in carbon cloth phenolic insulators exposed to SRM nozzle environments. A particular historical test motor is used as a demonstration case. The system response quantities of interest are the erosion depth and char depth. A representative model and input uncertainty are provided, and a sensitivity analysis is performed to identify influential parameters. Uncertainties in the numerical models and inputs are propagated through a two-dimensional uncertainty quantification methodology using a Latin Hypercube Sampling approach. The results show that the primary sources of uncertainty in SRM nozzle thermal modeling are the heat transfer coefficient, incident radiation heat flux, char material thermal conductivity, virgin material density, char material density, char material specific heat, and pyrolysis gas enthalpy. Uncertainties in the predictions of nozzle insulation erosion and char for the test case are provided relative to the nozzle location at the 99 th percentile and 95th confidence interval. Uncertainty in the char depth is roughly [Formula: see text] along the entire axial length of the nozzle. Uncertainty in the erosion depth ranges from about [Formula: see text] for the entrance and throat regions to [Formula: see text] at the nozzle exit.
Mutluluk Ekonomisi Üzerine Ölçek Geliştirme ve Uygulama
Authors: POLAT Mehmet
Published: September 2023

Bu çalışma, iki temel amaç üzerine bina edilmiştir. Birincisi, mutluluk ekonomisi bağlamında bir mutluluk ölçeği geliştirmektir. İkincisi, güvenirliği ve uygulanabilirliği ispatlanan mutluluk ölçeğini belirlenen modeller çerçevesinde test etmektir. Bu bağlamda çalışmanın ilk aşamasında, ölçek geliştirme aşamaları tek tek takip edilerek açıklayıcı ve doğrulayıcı faktör analizi yapılmıştır. Analizler neticesinde güven, beklenti, ekonomik kazanç ve yaşam standardı (EKYS) ve öznel iyi oluş (ÖİO) olmak üzere dört faktör elde edilmiştir. İkinci aşamada ise geliştirilen mutluluk ölçeği, Çoklu Grup Yapısal Eşitlik Modeli (ÇGYEM) kullanılarak belirlenen iki model kapsamında değerlendirilmiştir. Çalışmanın her iki modelinin neredeyse tüm grup sonuçlarında, bireylerin güven, beklenti ve EKYS düzeylerinin önemli düzeyde ÖİO üzerinde pozitif ve anlamlı etkiye sahip olduğu gözlemlenmiştir. Özellikle erkeklerin güven ve EKYS düzeylerinin beklentiler üzerinden ÖİO düzeyini önemli düzeyde etkilediği görülmüştür. Çıkan sonuçlara göre araştırma modellerinde yer alan aracı ve bağımsız değişkenlerin yeterli olduğu söylenebilir. Ayrıca bireylerin güven, ekonomik kazanç ve yaşam standartlarının gelecekle ilgili beklentilerini önemli düzeyde etkilediği ve beklentilerinin de mutluluk üzerinde önemli düzeyde belirleyici olduğu sonucu ortaya çıkmaktadır.
Optimization Production and Characterization of Bacterial Cellulose from Cornhusk
Authors: Widyastuti Fikka Kartika , Kartika Fitri Ayu Chandra
Published: September 2023

Cornhusks are agricultural wastes with low economic value that will cause environmental pollution if not appropriately handled. Cornhusk waste can be processed as raw material for bacterial cellulose (nata) since it contains 44% cellulose. This study aims to optimize bacterial cellulose production from cornhusks and determine the effect of cornhusk mass and fermentation duration on the characteristics of the nata produced. The primary process for producing bacterial cellulose from cornhusks was fermentation by Acetobacter xylinum. The nata characterization carried out in this study includes thickness, yield, crude fiber, and moisture content, as well as statistical analysis to determine whether there was significant effect of variations in cornhusk mass and fermentation duration on bacterial cellulose production. Based on the results of optimizing the production of nata from cornhusks, the optimal mass of cornhusks was of 25 grams with fermentation duration of 17 days. Based on the characterization and data analysis results, variation on the cornhusks mass and duration of the fermentation had a significant effect on fiber content, yield, and tensile strength of bacterial cellulose from cornhusks. On the other hand, the variations on cornhusks mass and the duration of fermentation did not significantly affect the moisture content and thickness of bacterial cellulose from cornhusks.
Performance Analysis of Ammonia Converter in Ammonia Unit Factory
Authors: Susmanto Prahady , Dewantara Dino , Widodo Teguh , Susanti Susi
Published: September 2023

An ammonia converter is a catalyzed reactor that facilitates the synthesis of NH3 (ammonia) from hydrogen (H2) and nitrogen (N2). Several studies have shown that the performance of this reactor significantly influences the operational efficiency and productivity of ammonia plants. Therefore, this study aims to evaluate the performance of an ammonia converter by assessing the effect of operating conditions on the reactant conversion and reaction products using design and actual data. The operating conditions examined included temperature, pressure, ratio of reactants, and inert mole utilized during the NH3 synthesis process. The results showed that the highest NH3 yield of 20.28% was achieved in actual data with 351.5oC temperature, 154.32 kg/cm2 pressure, 3.58 raw material ratio, and 3.57% inert mole (sixth dataset). The performance efficiency of an ammonia converter can be assessed using temperature, reactant ratio, and inert moles, while the pressure factor was insignificant due to dataset fluctuations. Based on the evaluation results, the converter experienced a decrease in performance due to a discrepancy in the existing operating conditions between the design and actual data.
Extraction of Basil Leaves Essential Oil using Microwave Assisted Hydrodistillation Method: Physical Characterization and Antibacterial Activity
Authors: Putri Ditta Kharisma Yolanda , Putri Salsabila Ananda , Nugraha Briantara Agung , Fachri Boy Arief , Palupi Bekti
Published: September 2023

Basil oil can be obtained from basil leaves by non-extraction methods, namely Microwave Assisted Hydrodistillation (MAHD). Therefore, this research aims to determine the yield percentage, essential oil composition by GC-MS, physical characteristics, and antibacterial activity of basil essential oil. The highest yield of 0.3076% was obtained at the optimum condition, which included a microwave power of 300 W, a mass-to-volume solvent ratio (F/S) of 0.75 g/mL, a raw material size of ± 1.75 cm, and an extraction time of 90 min. The results of the analysis of variance showed that all process parameters used had a significant effect on the yield obtained. Basil oil exhibited a larger inhibition zone against Escherichia coli bacteria (16.38 mm) which tended to be stronger than Staphylococcus aureus (5.95 mm) and was classified as moderate. The main components contained in the basil oil were E-Citral (46.79%) and Z-Citral (38.17%). The physical characteristic test showed that the basil oil was soluble in 96% ethanol after a ratio of 1:9, with 1 ml of basil oil compared to 9 ml of ethanol. The density of basil oil at 0.961 g/mL also complied with the standard value according to the Essential Oil Association (EOA) of Ocimum basilicum Essential Oil. These results showed revealed that the parameter analyzed using oil yields at operating conditions produced the most optimum yield value.
Analysis of Students‘ Error in Learning of Quadratic Equations : Systematic Literature Review
Authors: Islamiyah Wafa , Suryadi Didi
Published: September 2023

Quadratic equations are an important topic in mathematics at the secondary school level because this topic is widely used in solving problems in subsequent materials such as functions, logarithms, trigonometry, and several other materials. However, many students still make mistakes in solving quadratic equation problems. This study aims to get an overview of student errors in solving quadratic equation problems. The method used in this research is a systematic literature review. After going through the inclusion and quality test stages, the literature reviewed was 12 articles. The results of this study show that there are several student errors in quadratic equation material, namely concept errors, procedural errors, and operation errors and the factors that cause them are students not understanding the problem well, not understanding the sequence of steps used to solve the problem, and not being careful in calculating the final result, forgetting, answering originally and rushing in calculating.
Analisis Miskonsepsi Siswa SMP dalam Menyelesaikan Soal Matematika Menggunakan Four Tier Diagnostic Test
Authors: Arda Fita Nofiana , Pujiastuti Heni , Rafianti Isna
Published: September 2023

Abstrak: Penelitian ini bertujuan untuk mengetahui jenis miskonsespsi yang dialami siswa SMP dalam menyelesaikan soal matematika menggunakan Four Tier Diagnostic Test. Penelitian ini menggunakan pendekatan kualitatif dengan metode deskriptif. Penelitian dilaksanakan di SMPN 1 Kota Tangerang Selatan, subjek penelitian siswa kelas VII-2 SMN 1 Kota Tangerang Selatan. Pemilihan subjek dengan teknik purposive sampling. Intrumen yang digunakan berupa tes diagnostik empat tingkat, wawancara dan dokumentasi. Dari hasil penelitian menujukkan bahwa subjek penelitian mengalami miskonsepsi teoritikal yang ditandai kesalahan siswa saat memilih alasan jawaban, kesalahan mendefinisikan konsep perbandingan senilai maupun berbalik nilai, kesalahan menuliskan satuan, salah dalam perhitungan serta tidak menuliskan kesimpulan diakhir. Miskonsepsi klasifikasional yang dialami siswa ditandai kesalahan siswa tidak menuliskan keterangan apa yang diketahui dan ditanya, tidak mengubah kalimat matematika kebentuk model matematikanya, kemudian miskonsepsi korelasional ditandai dengan kesalahan siswa dalam menentukan dan menggabungkan rumus yang tepat untuk menyelesaikan permasalahan.

Kata kunci: Miskonsepsi; Four Tier Diagnostic Test; Perbandingan
Validasi E-Modul Berbasis Radec Materi KPK Dan FPB Kelas IV Sekolah Dasar
Authors: Yuza Arlina , Madona Ade Sri , Azkiya Hidayati , Yulisna Risa , Harun Gustiayu Juita
Published: September 2023

Penelitian bertujuan untuk mendeskripsikan validitas e-modul matematika berbasis model RADEC pada materi KPK dan FPB kelas IV SD. Metode penelitian yang digunakan adalah penelitian pengembangan dengan model pengembangan ADDIE. Penelitian dibatasi sampai tahap Development. Terdapat tiga ahli yang memvalidasi e-modull yaitu ahli media, ahli materi, dan ahli desain. hasil validasi E-modul matematika berbasis Model RADEC mencapai kategori valid dengan hasil rata-rata 89,07%. Hal ini menggambarkan bahwa E-modul yang dikembangkan sudah layak dan dapat digunakan dalam proses pembelajaran. Sedangkan untuk hasil uji praktikalitas oleh pendidik mendapatkan nilai rata-rata 92,82%dengan kategori sangat praktis, hal ini menandakan bahwa E-modul yang dikembangkan dapat membantu dan memudahkan pendidik dalam memberikan penjelasan yang benar terhadap materi pembelajaran kepada peserta didik khususnya dengan adanya pengaplikasian langkah-langkah model RADEC di dalamnya, yakni Read-Answer-Discuss-Expalin-Create.
Pengembangan Instrument Tes Berbasis Asesmen Kompetensi Minimum Materi Trigonometri Pembelajaran Matematika Kelas X SMA
Authors: Wahyudi Erik
Published: September 2023

Jenis penelitian ini adalah research and development (R&D). penelitian ini menggunaka metode penelitian ADDIE yang terdiri dari lima tahapan yaitu Analysis, Design, Development, Implementation, dan Evaluation. Tujuan dari penelitian ini adalah untuk mengembangkan instrument tes berbasis asesmen kompetensi minimum (AKM) pada materi trigonometri. Teknik pengumpulan data yang digunakan dalam penelitian ini, yaitu dokumen, lembar validasi, dan tes. Subjek dalam penelitian ini adalah siswa kelas X SMA Shailendra Palembang. Instrumen Tes berbasis AKM yang dikembangkan sebanyak 10 butir soal yang terdiri dari pilihan ganda komplek (PGK), isian, uraian. Hasil validasi ahli pengembangan instrument tes yang memperoleh tingkat kevalidan yaitu pada validitas kontes sebesar 0,867, aspek konstruk sebesar 0,833, aspek bahasa sebesar 0,911, dan rata-rata validitas keseluruhan atau Aiken’s sebesar 0,870 yang dapat dinyatakan valid. Sedangkan validitas secara empiris yang menggunakan rumus 10 soal dinayatakan valid dan hasil realibilitas rumus Cronbach Alpha yaitu  16rhitung 0, 764â‰¥rtabel 0,3291">  yang dikategorikan realibilitas tinggi. Maka dapat disimpulkan bahwa instrument tes berbasis Asesmen Kompetensi Minimum (AKM) pada materi trigonometri dikelas X SMA Shailendra dinyatakan valid dan reliabel serta layak untuk digunakan.
Analisis Kemampuan Penyelesaian Masalah Matematika di Masa Pandemi Ditinjau dari Self Regulation dan Gaya Kognitif Konseptual Tempo
Authors: Soemantri Sandha , Susanti Fery Alhadi
Published: September 2023

Salah satu dampak positif dari pandemi Covid-19 adalah percepatan transformasi pendidikan melalui pembelajaran jarak jauh, akibatnya metode pembelajaran harus terus dikembangkan dan siswa dituntut untuk mampu menjadi pembelajar mandiri. Self-regulated learning memiliki peran yang sangat penting dalam mencapai tujuan pembelajaran khususnya dalam pembelajaran matematika, karena dengan Self-regulated learning siswa mampu mengembangkan strategi untuk meningkatkan potensi dan mengelola lingkungan yang kondusif. Pembelajaran matematika yang selalu berkaitan dengan penyelesaian masalah melalui soal cerita menjadi cukup sulit bagi siswa jika pembelajaran dilakukan secara daring. Selain self-regulated learning, gaya kognitif siswa juga memiliki peran penting dalam kemampuan penyelesaian masalah khususnya soal cerita. Gaya kognitif yang cocok untuk keterampilan penyelesaian masalah adalah gaya kognitif tempo konseptual (Impulsif dan Reflektif). Dari penelitian ini ditemukan bahwa terdapat siswa dengan gaya kognitif reflektif dan memiliki self regulated learning yang tinggi, namun memiliki kemampuan penyelesaian masalah pada kategori rendah. Hal ini bertentangan dengan anggapan bahwa siswa reflektif mampu mengambil keputusan secara teratur. Akan tetapi, hasil penelitian secara keseluruhan menunjukkan bahwa siswa reflektif masih lebih baik dalam memecahkan masalah dan mengambil keputusan serta lebih mampu menentukan tujuan belajarnya sendiri. dan berkonsentrasi pada informasi yang relevan, sehingga memiliki standar kinerja yang tinggi.
Analisis Strategi Pemasaran di UD. XYZ Menggunakan Metode SWOT
Authors: Widodo Wahyu , Zainal Muttaqin Aan , Untari Erny
Published: September 2023

Abstrak
Kulit merupakan salah satu bahan baku dari barang pakai seperti tas, sepatu, dan jaket. UD. XYZ merupakan salah satu usaha yang bergerak dibidang penyamakan kulit sebagai bahan baku pembuatan sepatu dan tas yang terbuat dari kulit. Untuk menentukan strategi pada UD. XYZ dalam menjalankan usahanya yaitu menggunakan tools yang bisa di terapkan yaitu analisis SWOT guna menentukan bagaimana strategi kedepannya yang harus dilakukan. Dalam penelitian ini didapatkan hasil yaitu 0,941 pada faktor internal dan 1,064 pada faktor eksternal yang menunjukan UD.XYZ berada pada strategi agresif yang artinya perusahaan memiliki peluang dan kekuatan untuk memanfaatkan kekuatan yang ada dengan cara mempertahankan kesesuaian barang demi menjaga kepercayaan dan menjalin hubungan baik dengan pelanggan, memanfaatkan kerjasama dengan pengrajin, pemasok dan pembeli dengan baik serta mengombinasikan alur pembelian yang mudah dengan memanfaatkan media sosial untuk meningkatkan penjualan.

Kata Kunci : Kulit, Strategi Pemasaran, SWOT.

 

Abstract

Leather is one of the raw materials for goods such as bags, shoes, and jackets. UD. XYZ is one of the businesses engaged in leather tanning as a raw material for making shoes and bags made of leather. To determine the strategy on UD. XYZ in running a business is using a tool that can be used, namely a SWOT analysis to determine how the future strategy should be done. In this study, the results obtained are 0.941 on internal factors and 1.064 on external factors which show UD.XYZ is on an aggressive strategy which means the company has the opportunity and strength to take advantage of existing strengths by maintaining goods in order to maintain trust and establish good relationships with customers, make good use of collaborations with craftsmen, suppliers and buyers and combine an easy purchasing flow by leveraging social media to increase sales.

 

Keywords: Leather, Marketing Strategy, SWOT.
Aktivitas Ekstrak Daun Salam Koja (Murraya koenigii (L.) Spreng) Sebagai Antibakteri Escherichia coli
Authors: Fauzan Mohammad Zulfa , Filzafati Rezha Ilzaningtyas , Hidayati Nasrul Rofiah , Setiawan Mohammad Arfi
Published: September 2023

Berbagai penyakit umumnya disebabkan oleh mikroorganisme yang menyebabkan infeksi dan diare. Escherichia coli merupakan bakteri yang menyebabkan penyakit saluran pencernaan, infeksi, dan diare.  Daun salam koja mengandung alkaloid, fenil propanoid, fenol, flavonoid, glikosida, monoterpenoid, polifenol, quinon, saponin, sesquiterpenoid, steroids, tanin, terpenoid, dan triterpenoid yang berdifat sebagai antibakteri. Penelitian ini bertujuan untuk mengetahui aktivitas ekstrak daun salam koja (Murraya koenigii (L.) Spreng) sebagai antibakteri. Daun salam koja diekstraksi dengan metode soxhlet. Ekstrak daun salam koja diuji antibakteri dengan metode cakram menggunakan bakteri E. coli. Pada hasil penelitian ini rendemen ekstrak etanol daun salam koja yang dihasilkan sebesar 33,4148 %, sedangkan ekstrak n-heksana daun salam koja sebesar 31,5160%. Aktivitas antibakteri ekstrak etanol daun salam koja sebesar 51%, ekstrak n-heksana daun salam koja sebesar 24%.  Dari penelitian ini dapat disimpulkan bahwa ekstrak etanol daun salam koja dan ekstrak n-heksana daun salam koja dapat digunakan sebagai antibakteri.
Transition Energy, Orientation Force and Work Done in Transitional Behavior Atoms: Formulating New Principles in Thermodynamics
Authors: Ali Mubarak
Published: September 2023

Studying basic parameters of heat and thermodynamics can explore new insights into science. Gaseous and solid atoms under transitional behaviors can explore remarkable advances in chemical and physical sciences. An anomaly in the first law of thermodynamics can be recognized explicitly when the transitional behaviors of atoms are in the study. By gaining transition energy, gaseous atoms undertake a transition state. Hence, the work performed by the gaseous atoms. Symbolically, a plus sign is needed to use for it. However, the transitions in solid atoms occur because of the absorbing transition energy. So, the work performance is in the minus sign. A force exerted on the gaseous atom electron is different from on the solid atom electron, where transition energy changes the potential energy of that electron, thus controlling the orientation force. An anomaly resolves by changing the equations of internal energy. On attaining the mid-states, gaseous and solid atoms introduce cooling and heat effects in elastically driven electronic states. A transition state between re-crystallization and liquid states can be considered a mid-state. In generating cooling or heating energy, an electron executes dynamics by remaining within the occupied energy knot. Thus, constantly driven electronic states of atoms cause disorder and irreversible cycles. The study presents a basic understanding of the first law of thermodynamics, cold and heat energy, entropy, and condensed matter science at the atomic and electronic levels under a new insight.
Localized-Normal Mode DVR for Terminal Alkyne CC Stretch Vibrations
Authors: Streu Kristina , Hunsberger Sara , Patel Jeanette , Wan Xiang , Daly Jr. Clyde A.
Published: September 2023

The terminal alkyne C≡C stretch has a large Raman scattering cross section in the “silent” region for biomolecules. This has led to many Raman tag and probe studies using molecules with this moiety. Computational investigation of these systems is vital to aid in the interpretation of the results. In this work, we develop a localized normal mode discrete variable representation (DVR) method for computing terminal alkyne vibrational frequencies and transition isotropic polarizabilities which can easily and accurately be applied to any terminal alkyne molecule. The errors of localization to the terminal alkyne moiety, anharmonic normal mode isolation, and discretization of the Born-Oppenheimer potential energy surface are quantified and found to oppose each other. This results in a method with low error compared to other anharmonic vibrational methods like VPT2 and experiment. Several density functionals are tested using the method, and TPSS-D3 is found to perform surprisingly well. Additionally, diffuse functions are found to be important for the accuracy of computed frequencies. Finally, the computation of vibrational properties like transition isotropic polarizabilities and the universality of the normal mode atomic displacements across molecules are demonstrated.
Liver-Type Fatty Acid Binding Protein (FABP1) Has Exceptional Affinity for Minor Cannabinoids
Authors: Shahbazi Fred , Mohammadzadeh Sanam , Meister Daniel , Tararina Valentyna , Aggarwal Vagisha , Trant John
Published: September 2023

Fatty acid binding protein 1 (FABP1) is a lipid transporter primarily expressed in the liver where it helps move fatty acids between lipid membranes. Inhibition of FABP1 has potential therapeutic implications for nonalcoholic fatty liver disease, metabolic syndrome & obesity, diabetes, and inflammatory & cardiovascular diseases. Curiously, FABP1 is known to bind to both endocannabinoids (ECs) and the major phytocannabinoids (PCs) with moderately high affinities. We have developed an in-silico model of the protein and validated it against experimental data. We then employed the model to predict the binding mode and affinities of minor cannabinoids (MCs) to FABP1. Our study predicts that the top ranked MCs 5-acetyl-4-hydroxy-CBG and CBGA bind stronger than fatty acids (FAs), ECs or PCs, and participate in the key interactions used to stabilize FABP1-FA complexes. This makes them promising starting points for the development of new therapeutics. The implications this has on considering the minor cannabinoids as low entropy isosteres of the fatty acids is also discussed.
Unveiling the Power of Negative Ion Mode ESI-MS: Identify-ing Species with Remarkable Signal Intensity and Collisional Stability
Authors: Warnes Benjamin , Chihabi Jasmine , Manthorpe Jeffrey
Published: September 2023

Electrospray ionization mass spectrometry has long been the standard and most prevalent ionization method in mass spectrometry to detect and analyze molecules of low volatility that are relevant biologically, environmentally, and industrially. However, only a small number of analyses are conducted in negative ion mode, which has led to a dog-matic bias toward positive ion mode despite advantageous properties of the negative polarity, including lower back-ground noise and divergent tandem mass spectrometry behavior. We hypothesized that this bias was rooted in the relatively poor ionization efficiency of anionic functional groups seen in biochemistry; to explore this notion herein we evaluated 25 ions based on three criteria: (1) signal intensity relative to a sodium dodecylsulfate internal stand-ard; (2) resistance to collision induced dissociation based on survival of the precursor ion; and (3) diagnostic tandem mass spectrometry behavior. Among these species, highly fluorous ions exhibiting weakly coordinating and hydro-phobic properties contributed to enhanced signal intensities. Trifluoromethanesulfonyl-containing ions proved to be unexpectedly labile, while tetrakis[3,5-bis(trifluoromethyl)phenyl]borate anion (23) and bis(nonafluoro-1-butane)sulfonimidate (25) were determined to be of optimal signal intensity with signal intensity ratios relative to sodium dodecylsulfate (12 + Na+) of 332.0% ± 25.0% and 939.0% ± 92.0%, respectively, as well as survival yields of 100.0% ± 0.0% and 72.6% ± 0.8% at –50 eV. To further emphasize their optimal signal intensity, ions tetrakis[3,5-bis(trifluoromethyl)phenyl]borate anion (23) and bis(nonafluoro-1-butane)sulfonimidate (25) were comparable in signal intensity across solvents of acetonitrile, methanol, isopropanol, water, and their respective 1:1 mixtures. Facile preparation of various salts of bis(nonafluoro-1-butane)sulfonimidate led to additional evaluation of cation effects where the signal intensity ratio ranged from 939.0% ± 92.0% to 3195.0% ± 145.0% across K+, NH4+, Na+, and H+ counter cations. The dogma of negative ion mode being less sensitive was then challenged by the analysis of the sig-nal intensity of ion 25 to tetra-n-butylammonium, tetra-n-butylphosphonium, and (4-methylphenyl)diphenylsulfonium cations. These experiments showed that 25 was more sensitive by between 136.2% ± 5.5% and 180.7% ± 13.8%, thereby successfully challenging the positive polarity bias.
Imine Reductase Cascades for the Synthesis of Saturated N-Heterocycles
Authors: Turner Nicholas , Ramsden Jeremy , Costa Bruna , Heath Rachel , Marshall James , Mangas-Sanchez Juan , Montgomery Sarah , Mulholland Keith , Cosgrove Sebastian
Published: September 2023

Saturated N-heterocycles constitute a vital scaffold for pharmaceutical chemistry, but are challenging to access synthetically, particularly in asymmetric mode. Here we demonstrate how imine reductases can achieve annulation through tandem inter and intramolecular reductive amination processes. Imine reductases were used in combination with further enzymes to access un-substituted, α-substituted and α,α’-disubstituted N-heterocycles from simple starting materials, in one pot and under benign conditions. The work was exemplified in regard to product scope and a new route to the valuable natural product nicotine was demonstrated.
Directional Multiobjective Optimization of Metal Complexes at the Billion-Scale with the tmQMg-L Dataset and PL-MOGA Algorithm
Authors: Kneiding Hannes , Nova Ainara , Balcells David
Published: September 2023

Transition metal complexes (TMCs) play a key role in several areas of high interest, including medicinal chemistry, renewable energies, and nanoporous materials. The development of TMCs enabling these technologies remains challenged by the need to optimize multiple properties within very large chemical spaces, in which the thirty transition metals can be combined with a virtually infinite number of ligands. In this work, we provide the open tmQMg-L dataset including 30K TMC ligands, which combines large chemical diversity with synthesizability. The charge and metal-coordination mode of the ligands were robustly defined with a novel algorithm based on graph and natural bond orbital theories. The tmQMg-L dataset was leveraged in the automated generation of 1.37M TMCs resulting from all possible combinations between a square planar palladium(II) scaffold and a pool of 50 different ligands. This TMC space was used to benchmark a multiobjective genetic algorithm (MOGA) that optimized two properties over a Pareto front; namely the polarizability (alpha) and the HOMO-LUMO gap (epsilon). The MOGA evolved 130 TMC hits with maximal (alpha, epsilon) values in a way that could be easily rationalized by analyzing the nature of the ligands selected. Instead of the traditional mutation and crossover of fragments within a single ligand, this MOGA implemented full-ligand genetic operations acting on all coordination sites, maximizing chemical diversity. Further, we extended this MOGA algorithm with the Pareto-Lighthouse functionality (PL-MOGA), which allows for controlling both the aim and scope of the multiobjective optimization over the Pareto front. In explicit spaces containing billions of TMCs, the PL-MOGA enabled the explainable generation of thousands of novel and highly diverse TMC hits. We believe that the combined use of the tmQMg-L dataset and PL-MOGA algorithm will facilitate the discovery of TMCs with optimal properties within untapped chemical spaces.
A Convergent Click Ligation Approach to the Synthesis of Triazole-incorporated PMOs and Evaluation of Hybridization Properties
Authors: Banerjee Arpan , Das Arnab , Ghosh Atanu , Gupta Abhishek , SINHA SURAJIT
Published: September 2023

The synthesis of Phosphorodiamidate Morpholino Oligonucleotides (PMOs) incorporating single triazole rings in the backbone has been achieved via Cu(I) catalyzed Azide-Alkyne cycloaddition reaction (CuAAC). The synthetic approach implemented, is convergent, involving the ligation of a 5'-azide PMO fragment to 3'-alkyne fragment both in solution and on solid support. To access the 3'-alkyne PMO fragment, we synthesized 3'-N-propargyl chlorophosphoramidate morpholino monomers for all four nucleobases. The resulting triazole-incorporated PMOs (TL-PMOs) have exhibited comparable or improved binding affinity towards complementary DNA/RNA strands compared to its regular analogs.
Thermoelectric Properties of the Bismuth Oxychalcogenides Bi2SO2, Bi2SeO2 and Bi2TeO2
Authors: Flitcroft Joseph , Althubiani Adel , Skelton Jonathan
Published: September 2023

We present a detailed theoretical study of the thermoelectric properties of the bismuth oxychalcogenides Bi2ChO2 (Ch = S, Se, Te). The electrical transport is modelled using semi-classical Boltzmann transport theory with electronic structures from hybrid density-functional theory, including an approximate model for the electron lifetimes. The lattice thermal conductivity is calculated using first-principles phonon calculations with an explicit treatment of anharmonicity, yielding microscopic insight into how partial replacement of the chalcogen in the bismuth chalcogenides impacts the phonon transport. We find very good agreement between the predicted transport properties and a favourable cancellation of errors that allows for near-quantitative predictions of the thermoelectric figure of merit ZT. Our calculations suggest recent experiments on n-doped Bi2SeO2 have achieved close to the largest ZT possible in bulk materials, whereas the largest reported ZT for Bi2TeO2 could be improved sixfold by optimising the carrier concentration. We also predict that much larger ZT > 2.5, competitive with the benchmark thermoelectric SnSe, could be obtained for Bi2SO2 and Bi2SeO2 with heavy p-type doping. This study demonstrates the predictive power of this modelling approach for studying thermoelectrics and highlights several avenues for improving the performance of the Bi2ChO2.
Multiphoton Imaging of Spatial Distribution, Coordination and Redox Environment of Uranium under Model Biogeochemical Conditions
Authors: Andrews Michael , Jones Debbie , Woodward Adam , Swinburne Adam , Lloyd Jonathan , Magennis Steven , Botchway Stanley , Ward Andrew , Natrajan Louise
Published: September 2023

Nuclear power is a sustainable zero-carbon energy source but requires generated radionuclide waste be remediated from contaminated lands. Legacy, mining and disposal activities all engender environmental contamination, particularly for uranium, which is the main component by mass being both radioactive and toxic. Microbial mediated redox transformations have been targeted as bioremediation techniques. Typically studied by bulk quantitative techniques or on fixed (dead) cells, an absence of techniques capable of quantitatively probing the distribution and environment of radionuclides in living cells has impeded repurposing such wastes. Here we demonstrate the use of two-photon luminescence microscopy utilizing the intrinsic optical properties of the uranyl cation (UVIO2 2+) to follow microbial processes at the sub-micron level in vivo. The fundamental multiphoton photophysical properties of key uranyl species have been determined, and two-photon imaging performed. The long-lived uranyl emission and inherent spatial control of two-photon excitation allows high-resolution, label free visualization of uranyl-containing biological material, while fluorescence lifetime mapping demonstrates the ability to visualize the microscopic redox conditions over the surface of uranyl-reducing bacterial cells.
Determining times to detection for large methane release events using continuously operating methane sensing systems at simulated oil and gas production sites
Authors: Chen Qining , Kimura Yosuke , Allen David
Published: September 2023

Methane release events with large instantaneous emission rates are significant sources of emissions in multiple oil and gas production regions. Large release events detections are generally based on short duration observations, such as observations from aircraft or satellites. To be included in annual emissions reporting, instantaneous emission rate observations must be coupled with an estimate of event duration. Continuously operating, fixed point methane monitoring systems provide a mechanism for narrowly constraining event durations, however even continuously operating monitoring systems do not detect releases from all emission sources at all times. A method for using continuous monitoring system data to evaluate time to event detection was developed and demonstrated using data from a monitoring network operating in the Permian Basin of west Texas. Time to detection for events depends on meteorological conditions, the number and precision of the sensors, the criteria used in defining a detection and the positioning of the sensors relative to emission sources. For the case study in the Permian Basin, the presence of a single monitoring system per site enabled a time to detection of large release events that averaged less than half a day, and the methodology for determining bounds on event duration is applicable to a wide range of locations and types of sites.
A New Perspective to University Students' Online Learning Self-Efficacy: A Structural Equation Modeling
Authors: DEMİR Seda
Published: September 2023

The aim of this paper is to examine the relationship between university students' online learning self-efficacy and academic self-efficacy using structural equation modeling and to create a statistically significant model for online learning self-efficacy. In the study, the cross-sectional survey model, one of the quantitative research methods, was used. The sample of the study consists of 322 university students studying in various programs and at different grade levels in the faculty of education in the 2022-2023 academic year. Demographic information form, academic self-efficacy scale, student’s engagement scale in online learning environments, online learning systems acceptance scale and online learning self-efficacy scale were used as data collection tools. The results obtained from the study indicated that academic self-efficacy had a positive and significant effect on student’s engagement in online learning environments and online learning systems acceptance, while student’s engagement in online learning environments and online learning systems acceptance had a positive and significant effect on online learning self-efficacy. In addition, academic self-efficacy was a stronger predictor for student’s engagement in online learning environments, and student’s engagement in online learning environments was a stronger predictor for online learning self-efficacy.
A Study on the Appearance of the Kahramanmaraş Earthquake on Social Media
Authors: GÖKMEN Esma
Published: September 2023

This study is aiming to reveal how the earthquake, dated February 6, 2023, with the epicenter of Kahramanmaraş, appears on social media. In the study, content analysis method was used, and a total of 500 images (still images with or without sound) shared with the hashtag "6 February" on İnstagram were examined and how the earthquake was reflected with these contents was tried to be determined. Shared images were classified under certain themes and recorded by counting. Then, the images selected as samples and the obtained numerical data were analyzed and interpreted qualitatively. This analysis enabled us to reveal the meanings and representations produced by the visuals. The results obtained in the study were also compared with the results of similar studies in the literature. As a result of the study, it was seen that the earthquake dated February 6, 2023 was heavily represented on social media with dramatic and manipulative posts.
Proyectos CDIO: experiencias de diseño implementación en la Universidad del Quindío
Authors: Aldana Gutiérrez Jorge Alejandro , Vera Tasamá Alexander , Marín Hurtado Jorge Iván
Published: September 2023

El currículo del programa de Ingeniería Electrónica se encuentra inmerso en el marco de educación en Ingeniería CDIO (Concebir, Diseñar, Implementar, Operar) otorgando una oportunidad única de formación a los estudiantes para interactuar con el entorno. En este plan de estudios se cuenta con los proyectos CDIO, espacios académicos vitales de desarrollo de soluciones en el entorno local y desarrollar habilidades para el desarrollo y gestión de proyectos en ingeniería, los cuales han sido estructurados con base en los siguientes lineamientos: 1. Gestión de la solución: definición y análisis del problema, establecimiento de criterios, consideración de posibles soluciones, selección de una solución, implementación y seguimiento de la solución; 2. Definición de roles: responsabilidades del profesor y los estudiantes en el proyecto; 3. Gestión de los interesados soportado en la gestión de proyecto del PMBOK®: identificación de los interesados, y gestión de la participación de los interesados en el proyecto; 4. Gestión de la alineación constructiva: alineación entre los resultados de aprendizaje previstos, las actividades de enseñanza-aprendizaje, y evaluación del aprendizaje. En este documento se describe la propuesta educativa y los resultados obtenidos. Entre los resultados se destacan proyectos desarrollados en cadenas de valor productiva como el café, el plátano y el bienestar ciudadano enmarcados dentro de los objetivos de desarrollo sostenible.
La cotutela de tesis doctoral como estrategia de internacionalización de los doctorados: experiencias de la Facultad de Ingeniería de la Universidad de La Sabana
Authors: Montoya Jairo
Published: September 2023

La internacionalización de la Educación Superior permite lograr fortalecer las dimensiones internacional e intercultural de los procesos de enseñanza-aprendizaje y de investigación. Entre los mecanismos más conocidos se encuentran: movilidad de estudiantes, docentes e investigadores, programas de doble titulación, proyectos de investigación conjuntos, internacionalización del currículo, conformación de redes, entre otros. Este artículo analiza la internacionalización de la investigación doctoral de la Facultad de Ingeniería de la Universidad de La Sabana, Colombia, como caso de estudio, a través de la estrategia de tesis doctorales en cotutela (doble titulación) internacional. La tesis doctoral en cotutela consiste en la elaboración por parte de un doctorando o doctoranda de una investigación a nivel doctoral en cualquier campo del conocimiento, entre dos universidades de diferentes países, y co-dirigida por al menos un investigador de cada una de las dos Universidades o Instituciones participantes. La Facultad de Ingeniería de la Universidad de La Sabana ha implementado la realización de tesis doctorales en cotutela como una estrategia para fortalecer tanto la internacionalización de los programas de doctorado como las redes de colaboración con universidades fuera de Colombia. Este artículo presenta los resultados obtenidos de esta estrategia tanto a nivel de formación científica como personal de los doctorandos y doctorandas participantes en dichos proyectos.