bluuebunny/crossref_metadata_2025 huggingface dataset:
Perancangan Sistem Pengatur Electrical Conductivity (EC) Air Menggunakan Kendali Logika Fuzzy
Authors: Rifai Ahmad , Sembiring Sarmayanta , Al Farissi Al Farissi , Karo Karo Donny Giovanna
Published: May 2021

Telah dirancang sebuah sistem pengatur electrical Conductivity (EC) air dengan menggunakan kendali logika fuzzy. Sistem pengatur ini berfungsi untuk memutuskan banyaknya volume air dengan EC rendah/tinggi yang harus ditambahkan untuk mencapai EC air pada penampungan sesuai dengan target yang di inputkan. Penambahan air dengan EC rendah/tinggi dilakukan dengan mengalirkannya menggunakan pompa DC dan diditeksi menggunakan water flow sensor dengan penutup aliran menggunakan selonoid valve untuk memastikan volume air yang dialirkan telah sesuai dengan hasil sistem pengatur. Input sistem ini terdiri dari nilai EC air penambah (air dengan EC rendah dan air dengan EC tinggi), target EC air pada penampungan yang diinputkan dengan keypad 4x4, nilai EC air pada penampungan yang diditeksi sensor Konduktivitas, dan volume air pada penampungan yang diditeksi dengan menggunakan sensor ultrasonik. Hasil pengujian menunjukkan sistem telah dapat berjalan dengan baik, dimana sistem dapat menditeksi volume air dengan menggunakan sensor ultrasonik dengan error rata-rata penditeksian jarak sebesar 1,92%, penditeksi EC dengan menggunakan sensor Konduktivitas telah dapat menditeksi EC dengan error rata-rata sebesar 1,91%, sistem pengatur volume penambah telah berfungsi dengan baik dengan error rata-rata sebesar 1,87% dan kendali logika fuzzy telah dapat mengambil keputusan banyaknya volume penambah yang harus diberikan untuk mencapai EC target pada penampungan dengan error rata-rata terhadap pengukuran EC setelah hasil pencampuran sebesar 4,17%.
Tinjauan Algoritma RoI (Region of Interest) Dengan Metode Pengambangan Otsu Dan Klasterisasi K-Mean; Hasil Dan Tantangannya
Authors: Widiyanto Didit
Published: May 2021

Akurasi sebuah klasifikasi citra ditentukan oleh pengklasifikasi.  Meskipun RoI (Region of Interest) tidak menentukan secara langsung akurasi, namun RoI menentukan lingkup klasifikasi citra.   Terdapat tiga algoritma yang dapat digunakan sebagai algoritma RoI yaitu; Balanced Histogram Thresholding (BHT), algoritma Otsu, dan algoritma klasterisasi K-Means.  Paper ini meninjau algoritma Otsu dan algoritma klasterisasi K-Means yang digunakan oleh lima peneliti.  Dari ke lima peneliti; tiga peneliti menerapkan algoritma Otsu dan dua peneliti menerapkan algoritma K-Means sebagai algoritma RoI. Setelah operasi RoI, ke lima peneliti menerapkan algoritma GLCM (Gray Level Co-occurance Matrix) sebagai pengekstraksi ciri tekstur.  Hasil ekstraksi ciri diklasifikasi dengan menggunakan berbagai pengklasifikasi antara lain SVM (Support Vector Machine), Naive Bayes, dan Decision Tree. Akhirnya dengan membandingkan hasil dari ke lima peneliti, akurasi tertinggi diperoleh sebesar 100% dengan pengklasifikasi SVM menggunakan algoritma Otsu sebagai algoritma RoI, dan akurasi terendah adalah sebesar52% yang menggunakan algoritma Otsu pada kanal S dari citra HSV (Hue, Saturation Value).
Perancangan Bot Untuk Monitoring Server Dari Serangan Distributed Denial Of Service Menggunakan JSON WEB Token
Authors: Rahman Arif Maulana , Seta Henki Bayu , Astriratma Ria
Published: May 2021

Untuk mengamankan sebuah server diperlukan sistem monitoring agar meminimalisir resiko jika terjadi percobaan intrusi. Contoh serangan yang dapat mengancam server adalah serangan DDOS (Distributed Denial of Service). Berdasarkan permasalahan tersebut, diperlukan sebuah bot untuk melakukan monitoring server dari serangan DDOS, dalam penelitian ini difokuskan serangan DDOS berjenis UDP Flooding dan SYN Flooding. Monitoring server memanfaatkan bot untuk mendeteksi serangan DDOS berjenis UDP Flooding dan SYN Flooding dengan membatasi jumlah paket yang dikirimkan kepada port yang dibuka oleh server, apabila jumlah paket yang dikirimkan lebih dari 100 paket per detik maka bot akan mengidentifikasi pengiriman tersebut sebagai serangan. Penerapan metode JSON Web Token agar bisa dioperasikan oleh bot admin server yakni dengan mengimplementasikan package JSON Web Token pada bot lalu memanggil fungsi encode agar JSON Web Token dapat melakukan enkripsi pada klaim yang berisikan data penyerang oleh bot, sehingga bot admin server dapat mengamankan klaim yang akan dikirimkan ke admin server.
Perancangan Chatbot Sebagai Pembelajaran Dasar Bahasa Jawa Menggunakan Artificial Intelligence Markup Language
Authors: Abilowo Krisanto , Santoni Mayanda Mega , Muliawati Anita
Published: May 2021

Bahasa Jawa merupakan salah satu bahasa daerah yang digunakan di Indonesia. Masyarakat Indonesia suku Jawa yang tinggal di luar provinsi Jawa Tengah, provinsi DI Yogyakarta dan provinsi Jawa Timur jarang atau bahkan tidak menggunakan bahasa Jawa. Penutur bahasa Jawa saat ini juga sedang menurun seiring dengan perkembangan teknologi. Jika kejadian ini terus terjadi ada kemungkinan suatu saat nanti bahasa Jawa dilupakan karena pelestarian bahasa Jawa sudah berkurang. Oleh karena itu, penulis ingin membuat media pembelajaran yang dapat membantu melestarikan bahasa Jawa dengan memanfaatkan perkembangan teknologi. Sistem yang dibuat merupakan sebuah chatbot yang menggunakan metode Artificial Intelligence Markup Language. Sistem tersebut akan memberikan materi mengenai tiga tingkatan yang ada dalam bahasa Jawa dan memberikan pertanyaan mengenai tiga tingkatan yang ada dalam bahasa Jawa kepada pengguna. Hasil yang diharapkan adalah sistem dapat membantu dalam pelestarian bahasa Jawa.
Pemanfaatan Pengolahan Citra dan Klasifikasi K-Nearest Neighbor pada Citra Telur Ayam
Authors: Kurniawan Mochamad Aryo Aji , Ermatita Ermatita , Falih Noor
Published: May 2021

Telur dapat dikategorikan menjadi dua dalam proses penetasan yaitu telur fertil (subur) dan telur infertil (gabuk). Pemeriksaan kesuburan (fertilitas) telur dapat dilakukan dengan meneropong telur itu sendiri biasa disebut dengan candling, dengan cara mendekatkan telur ke sumber cahaya agar dapat menembus cangkang telur. Proses identifikasi seringkali dilakukan dengan proses manual oleh para peternak telur sehingga akan lebih membutuhkan kejelian dalam melakukan hal tersebut dan memperbesar kemungkinan salah dalam mengidentifikasinya. Berdasarkan hal tersebut tujuan penelitian ini dilakukan guna mengidentifikasi telur ayam fertil dan telur ayam infertil dengan mengekstrasi ciri warna pada telur tersebut menggunakan metode Hue saturation Values (HSV) dan menggunakan klasifikasi menggunakan Algoritma K-Nearst Neighbor (KNN) guna untuk membantu proses pengolahan citra digital. Dengan metode K-NN didapatkan akurasi sebesar 100% pada percobaan K=1.
Aplikasi Konseling Siswa Berbasis Web (Stusi Kasus: SMA Negeri 41 Jakarta)
Authors: Bandiyani Mia Setya , Husna Kholifatul , Krisnanik Erly
Published: May 2021

Bimbingan Konseling merupakan suatu program dari guru Bimbingan Konseling di setiap sekolah. Begitupun juga di Sekolah Menengah Atas Negeri 41 Jakarta. Kurangnya data informasi yang diperoleh siswa setelah siswa melakukan bimbingan (Hasil Bimbingan). Serta kurangnya rekaman simpanan data pendukung untuk melakukan bimbingan tersebut. Baik nilai, data siswa, maupun rekam jejak hasil bimbingan tersebut. Perihal rekaman simpanan data nilai,data siswa dan hasil bimbingan siswa diatas mengakibatkan antrian untuk melakukan bimbingan cukup rumit. Oleh karena itu perlu di bangunnya rancangan sistem informasi konseling agar memudahkan guru BK dalam mendapat rekaman data nilai, biodata siswa dan aspek aspek pendukung. Serta memudahkan Siswa untuk mengajukan bimbingan serta memperoleh rekaman data hasil bimbingan tersebut. Guna mengurangi antrian pengajuan bimbingan. Aplikasi Konseling Siswa ini berbasis web menggunakan bahasa program PHP dan data penyimpanan MYSQL (PHP MYADMIN), rancangan sistem yang akan dibuat di gambarkan dengan diagram unified Modelling Language atau UML, dengan menggunakan metodologi pendekatan waterfall, dan metodelogi analisis PIECES, harapan adanya pengelolaan berkas atau data – data konseling siswa menjadikan konseling / bimbingan siswa mejadi efektif serta efisien dan bagi siswa dalam melakukan dan mendapatkan konseling siswa di guru BK nya tersebut. Kata kunci : Konseling, Unified Modelling Language (UML), Metode Waterfall, metode analsis PIECES.
Air-Conditioning and the Transmission of COVID-19 in Indoor Environment
Authors: Oye Tosin T. , Gupta Naren , Goh Keng , Oye Toyosi K.
Published: May 2021

Substandard ventilation in restricted air-conditioning indoor places is allied with upsurge in the respiratory infections’ transmission. There have been several COVID-19 spread occurrences connected with indoor environment, together with a few from pre-symptomatic situations. Ventilation role in averting coronavirus transmission is not precise (i.e., through inhibiting transmission of an infectious dose to susceptible individuals or preventing the spreading of contagious particles to lessen the risk of transmission). SARS-CoV-2 is believed to be mainly spread through significant respiratory droplets, nevertheless, a growing amount of epidemic information associate aerosol role in the epidemics of coronavirus. Aerosols comprise of droplet nuclei and little droplets which stay in the air for longer than significant droplets. Recent studies show that coronavirus particles can stay transmissible on numerous substances, including aerosols within the indoor environments, as well as the contagion period contingent on humidity and temperature. Thus far, COVID-19 transmission via air-conditioning systems is unclear, but it is considered possible.
Holistic Modelling and Parametric Study of Bathroom Solar Hot Water Heating System
Authors: Oye Toyosi K. , Gupta Naren , Goh Keng , Kerrouche Abdelfateh , Oye Tosin T.
Published: May 2021

One of the major issues facing the world in the 21st century is climate change. However, sustainability has become a crucial concept to combat extreme consumption of environmental resources. The bathroom has been estimated to be the principal user of environmental resources in United Kingdom households. Therefore, the challenge that how a combined water and energy saving unit in the bathroom will contribute to the sustainability of the houses will remain unresolved. While the use of solar hot water technologies has been fundamental for energy efficiencies, this study reckons that lack of significant energy saving, and efficiency issues are based on the use of individual components and technologies it employed and concludes that a holistic approach is required to combat this issue. The method this study presented adopts conceptual and mathematical concept that is based on holistic modelling to design for a bathroom unit using Polysun program. Parametric analysis was also conducted to know how change in variable parameters like location, load and switch-on temperatures will affect the performance of the system designed. This study uncovers the contribution of renewable energy source in the bathroom and the significant contribution it makes in levels of energy consumption and carbon emissions which is attributed to the sustainability of the bathroom system and contribution this in turn makes to tackle the climate change as part of a sustainability-based strategy.
Combating Online Hate Speech through Critical Digital Literacy: Reflections from an Emancipatory Action Research with Roma Youths
Authors: Agapoglou Theodora , Mouratoglou Nikolaos , Tsioumis Konstantinos , Bikos Konstantinos
Published: May 2021

Despite the new and unprecedented opportunities for communication and networking in online settings, several challenges have arisen. One such challenge is the deviating behavior of social media users which is usually manifested through hate speech comments, often targeting minorities. For instance, the Roma minority constitutes one of the most discriminated groups, both online and offline. In this context, a significant lack of empirical research evidence can be observed regarding the exposure of minorities to online hate speech and the violation of their human rights. In this regard, the present paper illustrates the reflections of an emancipatory action research implemented with a group of Roma youths in Greece and discusses the impact of critical digital literacy activities on participants’ awareness regarding online hate speech. Based on participants’ views, the most empowering experience from this action research refers to the acquaintance of deliberating knowledge and skills in terms of producing non-violent counter-narratives.
Verification of the delivered patient radiation dose for non‐coplanar beam therapy
Authors: Kutuzov Ivan , Van Beek Timothy , McCurdy Boyd M.C.
Published: May 2021

Purpose

There is an increased interest in using non‐coplanar beams for radiotherapy, including SBRT and SRS. This approach can significantly reduce doses to organs‐at‐risk, however, it requires stringent quality assurance, especially when a dynamic treatment couch is used. In this work, new functionality that allows using non‐coplanar beam arrangements in addition to conventional coplanar beams was added and validated to the previously developed in vivo dose verification system.

Methods

The existing program code was modified to manage the additional treatment couch parameters: angle and positions. Ten non‐coplanar test plans that use a static couch were created in the treatment planning system. Also, two plans that use a dynamic treatment couch were created and delivered using Varian Developer mode, since the treatment planning system does not support a dynamic couch. All non‐coplanar test trajectories were delivered on a simple geometric phantom, using an Edge linear accelerator (Varian Medical Systems) with the megavoltage imager deployed and acquiring megavoltage transmission images that were used to calculate the delivered 3D dose distributions in the phantom with the updated dose calculation algorithm. The reconstructed dose distributions were compared using the 3D chi‐comparison test with 2%/2mm tolerances to the corresponding reference dose distributions obtained from the treatment planning system.

Results

The chi‐comparison test resulted in at least a 97.0% pass rate over the entire 3D volume for all tested trajectories. For static gantry, static couch non‐coplanar fields, and non‐coplanar arcs using dynamic couch the pass rates observed were at least 98%, while for the static couch, non‐transverse coplanar arc fields, pass rates were at least 97%.

Conclusions

A model‐based 3D dose calculation algorithm has been extended and validated for a variety of non‐coplanar beam trajectories of different complexities. This system can potentially be applied for quality assurance of treatment delivery systems that use complex, non‐coplanar beam arrangements.
Microstructure and Mechanical Properties of AZ31B Magnesium Alloy via Ultrasonic Surface Rolling Process
Authors: Geng Jilong , Yan Zhifeng , Zhang Hongxia , Liu Yongquan , Dong Peng , Yuan Shuo , Wang Wenxian
Published: May 2021

Ultrasonic surface rolling process (USRP) is a recently developed surface nanocrystallization technology which introduces ultrasonic into surface mechanical rolling technology. By means of USRP, a near‐polished,gradient nanostructured surface and high compressive residual stresses were generated on the AZ31B magnesium alloy. The electron backscattered diffraction is used to characterize the microstructure. It was found that the twinning was the main deformation mechanism in tensile test, while grain refinement and twinning were dominant during the USRP. The results show that the thick of affected layer was up to 600 μm and consisted of three layers: an ultrafine grain layer with thickness of about 180 μm on the topmost surface, a fine grain transition layer under ultrafine layer up to 420 μm and a twin layer distributed from the surface to 600 μm. Combined with Schmid factor (SF), evolution of twins and texture were analysed and were responsible for improvement of strength.
Biocompatible Blends of an Intrinsically Conducting Polymer as Stretchable Strain Sensors for Real‐Time Monitoring of Starch‐Based Food Processing
Authors: Zhang Lei , Li Jianmin , Yue Shizhong , He Hao , Ouyang Jianyong
Published: May 2021

Because stretchable strain sensors that have a resistance or capacitance sensitive to strain can sense skin deformation during physical movement, they have been extensively studied as wearable devices for healthcare monitoring. In principle, they can be used to monitor starch‐based food processing in real time, since starch‐based food can have remarkable volume change during processing. Monitoring starch‐based food processing in real time can help achieve high quality and high productivity while reducing energy consumption. Nevertheless, there is no such report in the literature. Here, a blend of starch and a biocompatible intrinsically conducting polymer, poly(3,4‐ethylenedioxythiophene): polystyrenesulfonate (PEDOT:PSS), is reported as a stretchable strain sensor to monitor starch‐based food processing including fermentation, steaming, storage, and refreshing in a real‐time manner. The resistance of the blends increases during the food volume expansion mainly caused by the fermentation, steaming, and refreshing, and it decreases as a result of the food volume shrinkage during cooling or storage. The signals can be thus used to optimize the processing conditions and control the food quality. This technology can be easily combined with the Internet of Things.
Bifunctional Therapeutic Peptide Assembled Nanoparticles Exerting Improved Activities of Tumor Vessel Normalization and Immune Checkpoint Inhibition
Authors: Taleb Mohammad , Atabakhshi‐Kashi Mona , Wang Yazhou , Rezvani Alanagh Hamideh , Farhadi Sabet Zeinab , Li Fenfen , Cheng Keman , Li Chen , Qi Yingqiu , Nie Guangjun , Ying Zhao
Published: May 2021

The effectiveness of cancer immunotherapy is impaired by the dysfunctional vasculature of tumors. Created hypoxia zones and limited delivery of cytotoxic immune cells help to have immune resistance in tumor tissue. Structural and functional normalization of abnormal tumor vasculature provide vessels for more perfusion efficiency and drug delivery that result in alleviating the hypoxia in the tumor site and increasing infiltration of antitumor T cells. Taking advantage of peptide amphiphiles, herein, a novel peptide amphiphile nanoparticle composed of an antiangiogenic peptide (FSEC) and an immune checkpoint blocking peptide (DPPA) is designed and characterized. FSEC peptide is known to be involved in vessel normalization of tumors in vivo. DPPA is an inhibitory peptide of the PD‐1/PD‐L1 immune checkpoint pathway. The peptide amphiphile nanoparticle sets out to test whether simultaneous modulation of tumor vasculature and immune systems in the tumor microenvironment has a synergistic effect on tumor suppression. Increased intratumoral infiltration of immune cells following vascular normalization, and simultaneously blocking the immune checkpoint function of PD‐L1 reactivates effective immune responses to the tumors. In summary, the current study provides a new perspective on the regulation of tumor vessel normalization and immunotherapy based on functional peptide nanoparticles as nanomedicine for improved therapeutic purposes.
Rapid Synthesis of Red‐Emitting Sr2Sc0.5Ga1.5O5:Eu2+ Phosphors and the Tunable Photoluminescence Via Sr/Ba Substitution
Authors: Yang Zhiyu , Zhou Yayun , Qiao Jianwei , Molokeev Maxim S. , Xia Zhiguo
Published: May 2021

Discovering new Eu2+‐doped red‐emitting phosphors in oxide‐based materials is a challenge for white light‐emitting diode (WLED) applications. Herein, a highly efficient high‐frequency induction heating method is employed to rapidly prepare the red‐emitting Sr2Sc0.5Ga1.5O5:Eu2+ phosphors peaking at 614 nm and exhibiting a high photoluminescence quantum yield of 78.4% under the excitation of 440 nm. The structural and spectral analyses suggest that Eu2+ ions tend to enter the [Sc1/Ga1O6] and [Ga2O6] polyhedrons with small coordination numbers, leading to the broadband red emission originated from large crystal field splitting of Eu2+ 5d level. The chemical substitution of Ba in the Sr site enhances the thermal stability and helps to the photoluminescence tuning from 614 to 728 nm in SrBaSc0.5Ga1.5O5:Eu2+. The WLED device fabricated by blending the red Sr1.7Ba0.3Sc0.5Ga1.5O5:Eu2+ and yellow Y3(Al, Ga)5O12:Ce3+ phosphors shows a high color‐rendering index (Ra = 91.1), and low color‐correlated temperature (CCT = 4750 K). This study aims to provide a new synthesis method and design principle for guiding the development of Eu2+‐doped oxide‐based red phosphors with low preparation cost; moreover, the photoluminescence tuning strategy via cation substitutions is essential to achieve tunable emission, even the near‐infrared luminescence.
Ultrafast Nanoscale Gradient Junction Self‐Powered Schottky Photodetectors for Vision‐Like Object Classification
Authors: Kumar Mohit , Lim Jaeseong , Park Ji‐Yong , Kim Sangwan , Seo Hyungtak
Published: May 2021

Emulating human vision for pattern classification is essential in intelligent machines, including pilotless vehicles and humanoid robots. Traditionally, analog visual information is captured by photosensors, which are sequentially classified using a physically separated algorithm‐based unit, such as a computer. Among such units, a self‐powered photodetector with a quick information sensing feature can be utilized for an unprecedented pattern classification; however, designing an ultrafast photodetector while maintaining a high sensitivity is critical. Herein, an alternative photovoltaic‐effect‐based, highly sensitive, self‐powered, broadband, ultrafast gradient junction nanoscale Schottky photodetector is introduced, that can sense input optical information without latency. Importantly, the proposed device can sense optical input within a ≈40 ns duration and demonstrate a 3‐dB bandwidth wider than 0.5 MHz, providing a throughput of 10 million bits per second. Photoconductive atomic force microscopy and Kelvin probe force microscopy independently revealed the photodynamic characteristic at a nanometer (≈35 nm) scale. Further, an array that can classify nontrivial patterns even with noisy inputs is developed. A unique solution to achieve an ultrafast photo response in self‐powered mode and classify the input patterns is provided. The proposed approach can be extended to several other artificial neural sensors, such as tactile, audio, and thermal sensors.
From Centrosymmetry to Noncentrosymmetry: Tailoring the Structural Arrangements of Carbonates with Strong Nonlinear Optical Response through Partial Anion Substitution
Authors: Meng Xianghe , Gong Pifu , Tang Chunlan , Yin Wenlong , Lin Zheshuai , Xia Mingjun
Published: May 2021

Second‐harmonic nonlinear‐optical (NLO) crystals with intrinsically noncentrosymmetric (NCS) structures are the core crystalline materials in the modern optics and laser technology. Here, taking as‐grown centrosymmetric NaY(CO3)2 and NCS YOHCO3 crystals as an example, a partial anion substitution strategy in the carbonate system is provided to develop NLO materials with remarkable NLO property for the first time, while the outstanding linear optical properties such as wide bandgap and large birefringence are maintained. Notably, benefiting from the planar π‐conjugated (CO3)2− anions and closed shell electronic structure of Y3+ cations, the YOHCO3 crystal simultaneously manifests a deep UV cutoff (<200 nm), sturdy second‐harmonic‐generation signal (2 × KH2PO4), and gigantic birefringence (0.07 at 1064 nm), enabling phase‐matching in short‐wavelength UV region. In addition, first‐principles calculations are conducted for the in‐depth analysis on the structure–optical property connection.
Dispersion Engineering for a Metastructure Composed of a High‐Contrast Subwavelength Grating and a Distributed Bragg Reflector
Authors: Zhang Jing , Liu Anjin
Published: May 2021

High‐contrast subwavelength grating (HCG) and distributed Bragg reflector (DBR) are demonstrated to be able to tailor the dispersion independently. Herein, it is found that multiple‐shape dispersions can be realized by a metastructure, which consists of an HCG on the DBR. Such a simple structure exhibits the linear dispersions with band‐edge modes, the M‐shaped dispersion with a cavity mode, and the W‐shaped dispersion with a bound state in the continuum. The origins of these dispersions and the mode characteristics (field distribution and quality factor) in the dispersions are studied. This study is helpful to realize single‐mode high‐efficiency surface‐emitting lasers, optical sensors, and quantum electrodynamics.
Regioselective Synthesis of Emission Color‐Tunable Pyrazolo[1,5‐a]pyrimidines with β,β‐Difluoro Peroxides as 1,3‐Bis‐Electrophiles
Authors: Ma Yangyang , Chen Yuanjin , Lv Leiyang , Li Zhiping
Published: May 2021

The synthesis and photophysical properties of fluorescent pyrazolo[1,5‐a]pyrimidines (PPs) are explored. An array of 5,7‐disubstituted fluorescent PPs are prepared selectively by using β,β‐difluoro peroxides as the 1,3‐bis‐electrophiles. The synthesized PPs display a fairly significant stokes shift (up to 211 nm) and a large window of tunable emission wavelength that covers most of the visible spectrum (400 nm to 800 nm). Theoretical calculation indicates that the distinguished variation of intramolecular charge transfer (ICT) ability upon the varied substituents is responsible for the color‐tunable fluorescence emission.

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A Photoinduced Multicomponent Regioselective Synthesis of 1,4,5‐Trisubstituted‐1,2,3‐Triazoles: Transition Metal‐, Azide‐ and Oxidant‐Free Protocol
Authors: Sai Allaka Bhargava , Basavoju Srinivas , Rama Krishna Gamidi
Published: May 2021

A transition metal‐ and azide‐free approach is explored to synthesize 1,4,5‐trisubstituted‐1,2,3‐triazoles under sunlight. The reaction proceeds via C−N and N−N bond formations. These regioselective 1,2,3‐triazoles are obtained from isatin Schiff bases, benzaldehydes and tosylhydrazine in the presence of base. This protocol offers the structurally diverse 1,2,3‐triazole derivatives with 75–90% yields.

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Using a browntop millet companion crop to aid native grass establishment
Authors: Richwine Jonathan D. , Keyser Patrick D. , Hancock Dennis W. , Ashworth Amanda J.
Published: May 2021

The lack of forage production during the seedling year is a barrier to wide‐scale adoption of native warm‐season grasses (NWSG). To address this, two NWSG establishment experiments were conducted in Knoxville, TN, 2016–2018, to determine the efficacy of big bluestem (BB; Andropogon gerardii Vitman) and switchgrass (SG; Panicum virgatum L.) establishment with browntop millet [BTM; Urochloa ramosa (L.) Nguyen] as a companion crop. Each experiment was a randomized complete block arranged as a 2 × 3 factorial. Two defoliation strategies [(1) harvests based on BTM maturity (boot to heading stage) for hay (HAY) or (2) clipping to control BTM competition by maintaining >50% sunlight reaching BB and SG seedlings (CLIP)] were coupled with three BTM seeding rates [0 (control), 11.2 (half‐recommended rate), and 22.4 (full‐recommended rate) kg pure live seed (PLS) ha−1]. Only BTM seeding rate affected BB and SG plant density at dormancy. In all cases, the control had greater BB and SG plant density than the full‐recommended rate, indicating that BTM impeded BB and SG establishment. All BTM seeding rates resulted in acceptable stands (≥5.4 plants m−2) of BB (both years) and SG (2017 only). Only the control allowed for acceptable stands of SG in 2016 (8.5 plants m−2). Managing BTM for HAY produced a mean cumulative dry matter (DM) yield of 3.15 and 2.68 Mg ha−1 in 2016 and 2017, respectively. These findings show that BTM can be a companion crop that helps offset production losses during BB and SG establishment.
The mechanisms of vascular aging
Authors: Wang Shan , Hu Song , Mao Yongjun
Published: May 2021

Vascular senescence is one of the hotspots in current research. With global average life expectancy increasing, delaying or reducing aging and age‐related diseases has become a pressing issue for improving quality of life. Vascular senescence is an independent risk factor for age‐related cardiovascular diseases (CVD) and results in the deterioration of CVD. Nevertheless, the underlying mechanisms of the vascular senescence have not been expressly illustrated. In this review, we attempt to summarize the recent literature in the field and discuss the major mechanisms involved in vascular senescence. We also underline key molecular aspects of aging‐associated vascular dysfunction in the attempt to highlight potential innovative therapeutic targets to delay the onset of age‐related diseases.
Multistage adaptive stochastic mixed integer optimization under endogenous and exogenous uncertainty
Authors: Motamed Nasab Farough , Li Zukui
Published: May 2021

To solve multistage adaptive stochastic optimization problems under both endogenous and exogenous uncertainty, a novel solution framework based on robust optimization technique is proposed. The endogenous uncertainty is modeled as scenarios based on an uncertainty set partitioning method. For each scenario, the adaptive binary decision is assumed constant and the continuous variable is approximated by a function linearly dependent on endogenous uncertain parameters. The exogenous uncertainty is modeled using lifting methods. The adaptive decisions are approximated using affine functions of the lifted uncertain parameters. In order to demonstrate the applicability of the proposed framework, a number of numerical examples of different complexity are studied and a case study for infrastructure and production planning of shale gas field development are presented. The results show that the proposed framework can effectively solve multistage adaptive stochastic optimization problems under both types of uncertainty.
A prediction model for the critical gas velocity and pressure gradient of continuous liquid‐carrying in inclined pipes
Authors: Wang Wu‐Jie , Cui Guo‐Min , Xiao Yuan , Chen Jia‐Xing
Published: May 2021

A generic model for the prediction of critical gas velocity and pressure gradient in slightly inclined pipes (β ≤ 6°) is presented in this article. The gas–liquid configuration was determined based on the minimum energy principle and consideration of wettability and surface tension. A visualization experiment was conducted to obtain the critical gas velocity and the critical pressure gradient of a gas–liquid flow through the 40 and 60‐mm pipe diameter. The theoretical study shows that the configuration is close to a convex interface shape at the critical conditions, which is in accord with the experimental phenomenon. Experimental study shows interfacial waves are the main cause of increased interfacial friction factor and a linear functional relationship between the inclination angle and the flow correction factor f(β). The results demonstrate that the new model is capable of providing satisfactory prediction results for the critical gas velocity, pressure drop, and liquid holdup.
Bootstrap aggregation accuracy gains in nearest‐neighbor nowcasting of Swedish gross domestic product
Authors: Jönsson Kristian
Published: May 2021

This article investigates the accuracy gains that can be made by applying bootstrap aggregation to K nearest‐neighbor nowcasting of Swedish gross domestic product. Using both a simulation‐based approach and a theoretical approach, the results indicate that substantial nowcasting accuracy gains can be made using bootstrap aggregation when considering one neighbor in the nowcasting algorithm, that is, when K = 1. Furthermore, a comparison of the simulation‐based and theoretical approaches to bootstrap aggregation indicates that using as few as 25 bootstrap replications can carry, in expectation, the simulation‐based results close to the theoretical results.
Comprehensive phenotyping of erythropoiesis in human bone marrow: Evaluation of normal and ineffective erythropoiesis
Authors: Yan Hongxia , Ali Abdullah , Blanc Lionel , Narla Anupama , Lane Joseph M. , Gao Erjing , Papoin Julien , Hale John , Hillyer Christopher D. , Taylor Naomi , Gallagher Patrick G. , Raza Azra , Kinet Sandrina , Mohandas Narla
Published: May 2021

Identification of stage‐specific erythroid cells is critical for studies of normal and disordered human erythropoiesis. While immunophenotypic strategies have previously been developed to identify cells at each stage of terminal erythroid differentiation, erythroid progenitors are currently defined very broadly. Refined strategies to identify and characterize BFU‐E and CFU‐E subsets are critically needed. To address this unmet need, a flow cytometry‐based technique was developed that combines the established surface markers CD34 and CD36 with CD117, CD71, and CD105. This combination allowed for the separation of erythroid progenitor cells into four discrete populations along a continuum of progressive maturation, with increasing cell size and decreasing nuclear/cytoplasmic ratio, proliferative capacity and stem cell factor responsiveness. This strategy was validated in uncultured, primary erythroid cells isolated from bone marrow of healthy individuals. Functional colony assays of these progenitor populations revealed enrichment of BFU‐E only in the earliest population, transitioning to cells yielding BFU‐E and CFU‐E, then CFU‐E only. Utilizing CD34/CD105 and GPA/CD105 profiles, all four progenitor stages and all five stages of terminal erythroid differentiation could be identified. Applying this immunophenotyping strategy to primary bone marrow cells from patients with myelodysplastic syndrome, identified defects in erythroid progenitors and in terminal erythroid differentiation. This novel immunophenotyping technique will be a valuable tool for studies of normal and perturbed human erythropoiesis. It will allow for the discovery of stage‐specific molecular and functional insights into normal erythropoiesis as well as for identification and characterization of stage‐specific defects in inherited and acquired disorders of erythropoiesis.
Recent Advances in Visible‐Light‐Driven Photocatalyzed γ‐Cyanoalkylation Reactions
Authors: Guin Soumitra , Majee Debashis , Samanta Sampak
Published: May 2021

Visible‐light‐induced photoredox‐catalyzed organic transformations through single‐electron‐transfer pathways have recently come to the limelight in modern organic chemistry. These innovative radical processes appear as ideal tactics for making a diverse set of pharmacologically and synthetically useful organic molecules under sustainable conditions. In this review, we summarize a brief overview of recent status of radical C(sp3)−X (X=C, S, Se, B, F, Cl etc) cross‐coupling reactions of cyclobutanone oxime esters as the surrogates of γ‐cyanoalkyl radicals with various kinds of radical acceptors using photocatalysts irradiated by visible light or natural sunlight. The efficiency of various metal‐salts (Ir, Ru, Cu, Pd etc) and metal‐free organic molecules (eosin Y, rose Bengal, 4CzIPN, HE, PhPTZ, Mes−Acr+ etc) as photocatalysts were thoroughly examined for the above conversions. Furthermore, the mechanism of the said reactions has also been presented. Notably, the described photocatalytic cycles would further bestow a new mechanistic concept for aiming a variety of cyanoalkylated scaffolds.
Base Promoted Intramolecular O‐arylation For The Synthesis of Dibenzo[b,f]oxepinones Toward Dihydroartocarpol D
Authors: Li Kaili , Zhang Kun , Huang He , Zhang Qianqian , Song Chuanjun , Chang Junbiao
Published: May 2021

An efficient base‐promoted intramolecular O‐arylation approach of 2‐halobenzyl 2‐hydroxyphenyl ketones toward the synthesis of dibenzo[b,f]oxepinones has been developed. The products are obtained in good to excellent isolated yields. Further extension of the strategy to the total synthesis of dihydroartocarpol D has been described.
Development of a self‐directed sinonasal surgical anatomy video curriculum: Phase 1 validation
Authors: Bailey C. Eric , Grauer Jordan S. , Chen Philip G. , Rangarajan Sanjeet V. , Chan Yvonne , Tewfik Marc A. , Marino Michael J. , Torabi Mohammad , Le Christopher H. , Chang Eugene H.
Published: May 2021

Background

Sinusitis is a common outpatient diagnosis made by physicians and is a reason for referral to otolaryngologists. A foundation in basic sinonasal anatomy is critical in understanding sinus pathophysiology and avoiding complications. Our objective in this study was to develop and to validate a self‐directed surgical anatomy video for medical students.

Methods

Two multimedia videos were developed highlighting sinonasal anatomy. In Video 1 we included audio narration and radiologic imaging. Video 2 incorporated highlighted images from a sinus surgery video. An assessment was developed to test sinonasal anatomy landmarks, spatial recognition of structures, and their clinical relevance. An expert panel of rhinologists scored face and content validity of the curriculum videos and assessment. Factor analysis was used to separate questions into face and content validity domains, and a one‐sample t test was performed.

Results

The panel scored face validity (Videos 1 and 2: 4.4/5) and content validity (Video 1: 4.5/5, 0.83; Video 2: 4.3/5, 0.75) significantly higher than a neutral response. There were no statistical differences for face or content validity between videos. The assessment was rated suitable (29%) or very suitable (57%) for testing basic sinonasal surgical anatomy, and the majority (71%) of respondents agreed (14%) or strongly agreed (57%) that the assessment thoroughly covered the sinus anatomy content with which medical students should be familiar.

Conclusion

We have developed two videos and an assessment that highlight and test sinonasal anatomy. Future studies will aim to identify whether the use of a self‐directed video curriculum improves sinonasal anatomy awareness and whether incorporation of surgical endoscopic videos augments training.
Gut Microbiome Signatures of Risk and Prodromal Markers of Parkinson Disease
Authors: Heinzel Sebastian , Aho Velma T. E. , Suenkel Ulrike , von Thaler Anna‐Katharina , Schulte Claudia , Deuschle Christian , Paulin Lars , Hantunen Sari , Brockmann Kathrin , Eschweiler Gerhard W. , Maetzler Walter , Berg Daniela , Auvinen Petri , Scheperjans Filip
Published: May 2021

Objective

Alterations of the gut microbiome in Parkinson disease (PD) have been repeatedly demonstrated. However, little is known about whether such alterations precede disease onset and how they relate to risk and prodromal markers of PD. We investigated associations of these features with gut microbiome composition.

Methods

Established risk and prodromal markers of PD as well as factors related to diet/lifestyle, bowel function, and medication were studied in relation to bacterial α‐/β‐diversity, enterotypes, and differential abundance in stool samples of 666 elderly TREND (Tübingen Evaluation of Risk Factors for Early Detection of Neurodegeneration) study participants.

Results

Among risk and prodromal markers, physical inactivity, occupational solvent exposure, and constipation showed associations with α‐diversity. Physical inactivity, sex, constipation, possible rapid eye movement sleep behavior disorder (RBD), and smoking were associated with β‐diversity. Subthreshold parkinsonism and physical inactivity showed an interaction effect. Among other factors, age and urate‐lowering medication were associated with α‐ and β‐diversity. Constipation was highest in individuals with the Firmicutes‐enriched enterotype, and physical inactivity was most frequent in the Bacteroides‐enriched enterotype. Constipation was lowest and subthreshold parkinsonism least frequent in individuals with the Prevotella‐enriched enterotype. Differentially abundant taxa were linked to constipation, physical inactivity, possible RBD, smoking, and subthreshold parkinsonism. Substantia nigra hyperechogenicity, olfactory loss, depression, orthostatic hypotension, urinary/erectile dysfunction, PD family history, and the prodromal PD probability showed no significant microbiome associations.

Interpretation

Several risk and prodromal markers of PD are associated with gut microbiome composition. However, the impact of the gut microbiome on PD risk and potential microbiome‐dependent subtypes in the prodrome of PD need further investigation based on prospective clinical and (multi)omics data in incident PD cases. ANN NEUROL 2021;90:E1–E12
Chemical Synthesis of Activity‐Based E2‐Ubiquitin Probes for the Structural Analysis of E3 Ligase‐Catalyzed Transthiolation
Authors: Liang Lu‐Jun , Chu Guo‐Chao , Qu Qian , Zuo Chong , Mao Junxiong , Zheng Qingyun , Chen Jingnan , Meng Xianbin , Jing Yangwode , Deng Haiteng , Li Yi‐Ming , Liu Lei
Published: May 2021

Activity‐based E2 conjugating enzyme (E2)‐ubiquitin (Ub) probes have recently emerged as effective tools for studying the molecular mechanism of E3 ligase (E3)‐catalyzed ubiquitination. However, the preparation of existing activity‐based E2‐Ub probes depends on recombination technology and bioconjugation chemistry, limiting their structural diversity. Herein we describe an expedient total chemical synthesis of an E2 enzyme variant through a hydrazide‐based native chemical ligation, which enabled the construction of a structurally new activity‐based E2‐Ub probe to covalently capture the catalytic site of Cys‐dependent E3s. Chemical cross‐linking coupled with mass spectrometry (CXMS) demonstrated the utility of this new probe in structural analysis of the intermediates formed during Nedd4 and Parkin‐mediated transthiolation. This study exemplifies the utility of chemical protein synthesis for the development of protein probes for biological studies.
Histological analysis of ankylothecodonty in Silesauridae (Archosauria: Dinosauriformes) and its implications for the evolution of dinosaur tooth attachment
Authors: Mestriner Gabriel , LeBlanc Aaron , Nesbitt Sterling J. , Marsola Júlio C. A. , Irmis Randall B. , Da‐Rosa Átila Augusto Stock , Ribeiro Ana Maria , Ferigolo Jorge , Langer Max
Published: May 2021

Dinosaurs possess a form of tooth attachment wherein an unmineralized periodontal ligament suspends each tooth within a socket, similar to the condition in mammals and crocodylians. However, little information is known about tooth attachment and implantation in their close relatives, the silesaurids. We conducted a histological survey of several silesaurid taxa to determine the nature of tooth attachment in this phylogenetically and paleoecologically important group of archosaurs. Our histological data demonstrate that these early dinosauriforms do not exhibit the crocodilian/dinosaur condition of a permanent gomphosis, nor the rapid ankylosis that is plesiomorphic for amniotes. Instead, all sampled silesaurids exhibit delayed ankylosis, a condition in which teeth pass through a prolonged stage where the teeth are suspended in sockets by a periodontal ligament, followed by eventual mineralization and fusion of the tooth to the jaws. This suggests that tooth attachment in crocodylians and dinosaurs represent the further retention of an early ontogenetic stage compared to silesaurids, a paedomorphic trend that is mirrored in the evolution of synapsid tooth attachment. It also suggests that the dinosaur and crocodylian gomphosis was convergently acquired via heterochrony or, less likely, that the silesaurid condition represents a reversal to a plesiomorphic state. Moreover, if Silesauridae is nested within Ornithischia, a permanent gomphosis could be convergent between the two main dinosaur lineages, Ornithischia and Saurischia. These results demonstrate that dental characters in early archosaur phylogenies must be chosen and defined carefully, taking into account the relative duration of the different phases of dental ontogeny.
Nursing students' experiences and perceptions of an anatomy laboratory session: Mixed methods study
Authors: Asman Oren , Kagan Ilya , Itzhaki Michal
Published: May 2021

Many nursing curricula do not offer anatomy laboratories and exposure to cadaveric material. In this mixed methods study, nursing students' perceptions and experiences from an anatomy laboratory session were examined. Students from two academic nursing programs (a four‐year general baccalaureate nursing program and a two‐year accelerated nursing program for non‐nursing baccalaureate graduates) took part in an anatomy laboratory session (N = 223). Participants' learning experiences, emotional experiences, and satisfaction with the anatomy laboratory session were assessed by their responses to closed‐ended questionnaires. Participants' reasons for participation and suggestions for improvement were examined by open‐ended questions. A mixed methods analysis of the data revealed a high level of satisfaction with the anatomy laboratory experience. Positive attitudes and learning experiences correlated with a sense of identification with the nursing profession. Satisfaction was positively associated with a perceived quality of learning and negatively associated with a negative emotional experience. Curiosity and self‐challenge, as well as the quest for tangible, in‐depth learning, were major motivators involved in the students' desire to participate in the session. Both qualitative and quantitative analyses indicated that the educational experience was significant. Therefore, it is recommended to integrate anatomy laboratory sessions into anatomy courses for nursing students. This will help to illustrate and assimilate classroom material and strengthen nursing students' sense of identification with their profession.
Knowledge creation through collaboration: The role of shared institutional affiliations and physical proximity
Authors: Stephens Bryan , Cummings Jonathon N.
Published: May 2021

This paper examines how shared affiliations within an institution (e.g., same primary appointment, same secondary appointment, same research center, same laboratory/facility) and physical proximity (e.g., walking distance between collaborator offices) shape knowledge creation through biomedical science collaboration in general, and interdisciplinary collaboration in particular. Using archival and publication data, we examine pairwise research collaborations among 1,138 faculty members over a 12‐year period at a medical school in the United States. Modeling at the dyadic level, we find that faculty members with more shared institutional affiliations are positively associated with knowledge creation and knowledge impact, and that this association is moderated by the physical proximity of collaborators. We further find that the positive influence of disciplinary diversity (e.g., collaborators from different fields) on knowledge impact is stronger among pairs that share more affiliations and is significantly reduced as the physical distance among collaborators increases. These results support the idea that shared institutional affiliations and physical proximity can increase interpersonal contact, providing more opportunities to develop trust and mutual understanding, and thus alleviating some of the coordination issues that can arise with higher disciplinary diversity. We discuss the implications for future research on scientific collaborations, managerial practice regarding office space allocation, and strategic planning of initiatives aimed at promoting interdisciplinary collaboration.