bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Concentration of Titanium Dioxide Nanoparticles on Their Antibacterial Activity in the Synthesis of Polyurethane Biopolymers
Authors: Budirohmi Andi , Mustari Yanti , Suriani Yunita , Adriana Vivi , Natsir Hasnah
Published: March 2024

In the health sector, the use of polyurethane (PU) as a basic material for medical devices still causes problems related to local and systemic infections. One of the most appropriate ways to overcome this problem is to synthesize PU biopolymer with titanium dioxide (TiO2) nanoparticles. The use of nano-shaped materials in this synthesis has many advantages, including being easier to synthesize and being antibacterial. Meanwhile, starch is the result of isolation from banana weevils, where banana weevils are agricultural waste that has not been utilized properly. Particle size and the use of agricultural waste are a form of modification and innovation in PU synthesis, as well as a novelty in the development of this research. In PU synthesis, several characterization techniques are carried out, including polymer tests, namely strain and stress, functional group analysis using (Fourier Transform Infra-Red), and antibacterial tests. Based on the results of the FTIR test analysis, it show that at a wave number of 1724.36 cm-1, the N-H functional group is visible, and the absorption of urethane and TiO2 groups is in the range of 513.07 cm-1. The mechanical properties test shows the strain (28.92 - 21.88% GL) and young's modulus in the interval (5.484-3.268 MPa). The antibacterial test showed that the inhibitory power of test samples A1 and A4 with diameters of 8 mm and 8 mm proved to be very effective in killing E. Coli bacteria, while test samples A1¹, A2¹, A3¹, and A4 were not able to kill E. Coli bacteria. S. Aureus. bacteria. The characterization results show that PU biopolymer can be used as a basic material for making bacterial decontaminant medical devices.
Description of Problem Solving Ability of Class X Students of Al-Azhar 10 Pontianak Islamic High School on Chemical Bonding Subject Material
Authors: Yani Tri Indri , Enawati Eny , Junanto Tulus , Muharini Rini , Rasmawan Rahmat
Published: March 2024

This research was conducted to determine the problem solving ability of class X students of Al-Azhar 10 Pontianak Islamic High School on chemical bonding material. The type of research is descriptive qualitative problem solving ability. The research subjects were X IPA 1 class students of Al - Azhar 10 Pontianak Islamic High School totaling 21 people. Data collection tools include test questions designed based on problem-solving and interview guidelines developed based on problem-solving—data collection techniques using measurement techniques and direct communication techniques, namely written tests and unstructured interviews.The results of the problem solving ability data analysis were calculated using a problem solving ability assessment instrument and were presented as a whole based on the problem solving criteria instrument. The results of the analysis obtained students' problem solving ability on chemical bonding material, namely indicators of understanding the problem 49% (sufficient), making a plan 56% (sufficient), implementing a plan 63% (good), and checking back 70% (good) with an average percentage of 60% (sufficient). So it can be concluded that students' problem solving skills on chemical bonding material have an adequate predicate.
Preliminary Study: Study of Supporting Facilities for Natural Science Mini Project Practicum Models of Junior High Schools in Mataram
Authors: Ardiansyah Bakhtiar , Ramdani Agus , Hakim Aliefman , Makhrus Muh
Published: March 2024

This study aims to describe the supporting facilities for the Natural Science Mini Project Practicum (PIMPA) model of learning from the availability of tools and chemicals as well as books or literature available in SMP throughout Mataram City. This research was conducted in three schools spread outside the urban areas of Mataram City, especially those located close to the tourism area of Mataram City, namely: SMPN 11 Mataram, SMPN 17 Mataram, and SMPN 21 Mataram. The research subjects were laboratories and libraries, and the research objects were laboratory support facilities. The form of activity carried out is the recording of documents (inventory) of laboratory equipment and their use in science practicum activities. The data from this study were analyzed descriptively qualitatively. The results of this study indicate that the laboratory carrying capacity in the PIMPA model is the availability of laboratory equipment for science practicum activities at SMPN 11 Mataram is 77.27% (adequate); SMPN 17 Mataram available 77.27% (adequate); and SMPN 21 Mataram available 72.72% (adequate).
Workshop Public Speaking Bagi Guru dan Siswa/I SMP Negeri 3 Marga, Tabanan, Bali
Authors: Sasongko Singgih , Narida Marshelia Gloria , Chandra Goldyron Erick , Pratiwi Nuning Indah , Haes Putri Ekaresty
Published: March 2024

Pengabdian kepada Masyarakat ini mengeksplorasi dampak workshop public speaking terhadap siswa/i SMP Negeri 3 Marga. Workshop ini bertujuan untuk mengembangkan keterampilan public speaking guna menghadapi tantangan masa depan. Melibatkan 27 peserta dari berbagai tingkat kelas, workshop mencakup pengenalan public speaking, diskusi interaktif, praktik langsung, dan penjelasan aspek visual, voice, dan verbal. Hasil penelitian menunjukkan antusiasme tinggi peserta dan peningkatan yang signifikan dalam keterampilan public speaking mereka. Penelitian ini memberikan bekal penting bagi siswa/i dalam situasi komunikasi sehari-hari, memperluas wawasan, dan membuka peluang karir di masa depan. Workshop public speaking ini berkontribusi positif dalam pengembangan keterampilan siswa/i SMP Negeri 3 Marga, dengan dampak jangka panjang yang positif bagi siswa/i, sekolah, dan Desa Wisata Pinge.

Kata Kunci: Workshop, public speaking, positif
A lipidanyagcsere eltéréseinek vizsgálata felnőtt hypertoniás betegek esetén adatbányászati módszerrel
Authors: Kovács Beáta , Németh Ákos , Daróczy Bálint , Karányi Zsolt , Maroda László , Diószegi Ágnes , Páll Dénes , Harangi Mariann
Published: March 2024

A hypertonia és a hyperlipidaemia együttes előfordulása gyakori, és közös jelenlétük fokozza a cardiovascularis megbetegedések kialakulásának kockázatát. Célul tűztük ki a lipidanyagcsere eltéréseinek vizsgálatát és annak összefüggését a testtömegindexszel (BMI) egy nagyméretű, felnőtt hypertoniás betegpopuláción adatbányászati módszerek alkalmazásával.
MARKA CİNSİYETİ İLE MARKA AŞKI İKLİŞKİSİNDE MARKA ÇEKİCİLİĞİNİN, MARKA ÖZGÜNLÜĞÜNÜN ARACILIK ROLÜ
Authors: Alizade Parisa
Published: March 2024

Son zamanlarda marka sevgisine dair yapılan çalışmaların sayısı artmaktadır. Yapılan çeşitli çalışmalarda marka aşkının öncülleri ve etkileri araştırılmıştır. Bu çalışmada marka sevgisinin öncülleri markanın cinsiyet özellikleri, marka çekiciliği ve marka özgünlüğü olmuştur. Bu çalışmanın amacı marka cinsiyetinin marka aşkı, marka çekiciliği ve marka özgünlüğü üzerindeki etkisine ve marka çekiciliğinin ve marka özgünlüğünün marka aşkı üzerindeki etkilerine bakmaktır. Ayrıca, çalışmanın diğer amacı marka cinsiyeti ile marka aşkı ilişkisinde marka çekiciliğinin ve marka özgünlüğünün aracılık etkisini araştırmaktır. Başka bir deyişle, bu çalışmada markanın cinsiyet özelliklerinin marka aşkı üzerinde doğrudan ve dolaylı etkiye sahip olup olmadığı araştırılmıştır. Bu ampirik çalışmada önerilen model Türkiye’de yaşayan ve çevrimiçi alışveriş platformlarından alışveriş yapanlar arasından 480 kişiye çevrimiçi olarak uygulanan anketlerle test edilmiştir. Yapısal modelin hipotezlerini test etmek için yapısal eşitlik modellemesi ile yol analizi yapılmıştır. Çalışmanın bulguları markanın cinsiyet özelliklerinin marka aşkı üzerinde doğrudan bir etkiye sahip olmadığını saptamıştır. Elde edilen bulgular markanın cinsiyet özelliklerinin marka çekiciliği ve marka özgünlüğü üzerindeki etkisini ve marka çekiciliğinin ve marka özgünlüğünün marka aşkı üzerindeki etkilerini onaylamıştır. Ayrıca, markanın cinsiyet özellikleri ile marka aşkı arasındaki ilişkide marka çekiciliğinin ve marka özgünlüğünün aracılık rolünün ortaya çıkması çalışmaya özgünlük kazandırmıştır. Başka bir ifadeyle, çalışmanın bulguları markanın cinsiyet özelliklerinin marka aşkını dolaylı olarak etkilediğini onaylamıştır.
DOLAYLAMA TERİMİNİN DİL BİLGİSEL YÖNÜ VE TARİHÎ TÜRKÇE METİNLERDE GÖRÜNÜMÜ
Authors: Karacan Neslihan
Published: March 2024

Zihinde var olan düşünceleri yansıtmak için kullanılan dilin kullanım biçimleri dilbilimcilerin sıklıkla irdelediği konulardan biridir. Dilin stilistik kullanımı sadece edebi metinlerin değil gündelik dilin de içinde görülmektedir. Stilistik bir olgu olarak “dolaylama” Türk dilinde çoğunlukla ince, estetik bir söyleyiş amacıyla ad aktarması ve istiare gibi söz sanatlarının yardımıyla oluşturulmaktadır. Ancak dünya literatüründe perifez olarak adlandırılan ve Türkçede “dolaylama” kavramıyla karşılanan, bir ifadenin tek bir sözcük yerine birden fazla sözcükle aktarılması olarak tanımlanan terimin Türk dili araştırmalarında sadece stilistik bir figür olarak işlendiği sıkça karşılaşılan bir durumdur. Bu çalışmada “perifez”in figüratif dil unsurlarından biri olmasının yanında dil bilgisel bir terim olarak perifez terimi üzerinde de durulmuştur. Eski Türkçedeki yansımaları ele alınarak işlenen perifez, tarihi süreç içerisinde tercihe dayalı olmayan ve günümüzde yerini çoğunlukla periferik yapılara bırakmış +(A)d-, +rAk, +sA-, +sIrA- morfo-sentaktik biçim birimler üzerinden ortaya konulmuştur. Ayrıca stilistik bir fenomen olarak perifez Türkçenin tarihi dönemler içerisindeki dil yadigarlarından örneklendirilerek görünümleri işlenmiştir. Bu vesile ile yeterince ilgi görmeyen dil bilgisel açıdan perifezin tarihi metinlerdeki görünüşleri ortaya konulması amaçlanmıştır. Perifez teriminin iki yönüne de dikkat çeken bu çalışma aslında perifezi hem dil bilgisel hem de edebi olarak iki başlıkta incelemesi ayrıca çalışmalarda genellikle eşzamanlı olarak örneklendirilen “dolaylama”nın daha kapsamlı ve art zamanlı görünümleri ortaya koyması açısından dil bilgisi ve anlam bilim çalışmalarına katkı sunmaktadır.
TURGUTOĞLU MUSA BEY VE İLİŞKİLERİ
Authors: ŞAFAKCI Hamit
Published: March 2024

Turgutoğulları, Karamanoğulları döneminde Konya ve çevresinde önemli roller üstlenmişlerdi. II. Mehmed tarafından 1467 yılında alınan Karaman bölgesinde Osmanlı düzeninin yerleşmesi uzun zaman almıştır. 1483 yılında Karamanoğlu Kasım Bey’in ölümüyle bölgenin siyasi önderliği Turgutoğulları tarafından yürütülmüştür. II. Bayezid döneminde Turgutoğlu Mahmud Bey aktif bir rol üstlenmişken Bayezid ve Selim dönemlerinde Turgutoğullarının liderliğinin Musa Bey’e geçtiği anlaşılmaktadır. Çalışmada bu nedenle Turgutoğlu Musa Bey’in devlet adamları ile ilişkileri üzerinde durulmuştur. Çalışmanın amacı, Turgutoğlu Musa Bey’in Şah İsmail’in adamı olduğu yönündeki genel kabulü tartışmaktır. Bu nedenle Şah İsmail’in bir mektubu ve Şehzade Ahmed’in dört hükmü değerlendirilmiştir. Bunların yanında tahrir defterleri ile çeşitli belgeler incelenmiştir. Araştırma sonucunda aynı aileden iki Musa olduğu anlaşılmıştır. Yine Musa Bey’in Şah İsmail’in adamı olmadığı belirtilmiştir. 1512 yılında Turgutoğullarından Musa Bey’e gönderdiği mektupta Şah İsmail, Karamanlı Ahmed Ağa’nın isteği üzerine harekete geçilmesini ve bölgede olanlardan haberdar edilmesini bildirmiştir. Yine Selim ile mücadelesinde Şehzade Ahmed mektup göndererek Musa Bey’den destek istemiştir. Osmanlılar iç çatışmaları bitirip Safevilere karşı üstünlük sağladıktan sonra Musa Bey’in timar tasarruf ettiği ve sefer zamanı asker gönderdiği anlaşılmaktadır. Karaman’ın önde gelenlerinden olan Musa Bey’e dair 1525 tarihli kayıt, hâlâ hayatta olduğunu gösterir. Bu çalışmada Musa Bey hakkında genel bilgiler verildikten sonra Turgutoğulları içerisindeki yeri ve Osmanlı idari düzeninde aldığı görevler ile siyasi olaylardaki rolleri üzerinde durulmuştur.
Struktur Komunitas Gastropoda Epifauna Intertidal di Perairan Desa Lampanairi Kecamatan Batauga Kabupaten Buton Selatan
Authors: Raiba Restiana , Ishak Ermayanti , Permatahati Yustika Intan
Published: March 2024

Gastropoda merupakan kelas terbesar dari filum moluska, yang berdasarkan keberadaannya terbagi menjadi gastropoda infauna dan epifauna. Tujuan penelitian ini adalah mengetahui struktur komunitas gastropoda epifauna di kawasan intertidal perairan Desa Lampanairi Kecamatan Batauga Kabupaten Buton Selatan. Pengambilan sampel gastropoda dengan menggunakan dua metode sampling yaitu transek kuadrat dan koleksi bebas. Gastropoda yang ditemukan terdiri atas 49 spesies, 29 genus, 18 famili, dan 5 ordo dengan jumlah total sebanyak 1 099 individu. Habitat lamun dengan kondisi substrat berpasir dan lumpur berpasir memiliki kepadatan tertinggi pada Famili Strombidae dan Nassariidae, sedangkan kepadatan terendah pada Famili Neritidae dan Naticidae. Habitat bebatuan dengan substrat kerikil, memiliki kepadatan tertinggi pada Famili Neritidae dan Turbinidae, sedangkan kepadatan terendah pada Famili Nassariidae. Indeks keanekaragaman dan keseragaman gastropoda berada pada kategori sedang, dengan indeks dominansi berada pada kategori rendah, dengan nilai masing-masing H’=2,10-2,31, E=0,66-0,74 dan D=0,14-0,22. Struktur komunitas gastropoda pada kawasan intertidal perairan Desa Lampanairi masih cukup baik dan tidak ada jenis yang mendominasi. Parameter fisika-kimia perairan, meliputi suhu, salinitas dan pH mendukung kehidupan gastropada dengan nilai masing-masing 29,75 0C, 28,33 ‰, dan pH 6,17.
Preferensi Habitat Spesies Chiton (Achantopleura spp.) di Daerah Intertidal Perairan Mandati Wakatobi
Authors: Rahmawati Reni , Bahtiar  , Permatahati Yustika Intan
Published: March 2024

Penelitian ini bertujuan untuk mengetahui variasi kepadatan, pola distribusi dan preferensi habitat chiton (Acanthopleura spp.) di daerah intertidal Perairan Mandati Kabupaten Wakatobi. Pengambilan sampel dilakukan dengan metode transek kuadrat selama 2 kali dalam dua minggu yaitu saat siang hari dan malam hari pada saat air laut sedang surut. Analisis data yang digunakan, meliputi kepadatan, pola distribusi menggunakan indeks dispersi morisita dan preferensi habitat menggunakan Principle Componen Analysis (PCA), serta untuk mengetahui kolerasi antara kepadatan chiton dan kondisi habitatnya melalui program XLSTAT 2015. Jenis chiton yang ditemukan di Perairan Mandati adalah A. spinosa pada malam hari dan A. gemmata pada siang hari. Nilai kepadatan A. spinosa berkisar antara 6,00 ind/m2-1,11 ind/m2, sedangkan A. gemmata berkisar antara 2,78 ind/m2-0,33 ind/m2. Indeks pola distribusi menunjukkan kedua jenis chiton memiliki pola distribusi seragam dan mengelompok. Preferensi habitat A. spinosa dicirikan oleh kondisi habitat dengan rugositas dan persentase tutupan Ulva sp. yang tinggi, sedangkan preferensi habitat A. gemmata dicirikan oleh kondisi habitat yang terendam dengan suhu air rendah, persentase tutupan alga jenis Ulva sp. dan rugositas yang tinggi.
Ultrastruktural Dan Mekanik Exoskeleton Kepiting Bakau (Scylla Sp.) Terhadap Ion Ca2+ Yang Dipelihara Pada Sistem Resirkulasi
Authors: Suriadi La , Idris Muhammad , Hamzah Muhaimin
Published: March 2024

ABSTRAK

Penelitian ini bertujuan untuk menguji pengaruh ion Ca2+  yang berbeda terhadap ultrastruktural dan mekanik exoskeleton kepiting bakau (scilla serrata) yang dipelihara pada sistem resirkulasi. Penelitian ini dilaksanakan pada bulan Oktober 2020-Desember 2020, yang bertempat di Perumahan Dosen Kampus Lama, Blok D1, Kel. Lahundape, Rt 002 Rw 004 Provinsi Sulawesi Tenggara. Kepiting  yang digunakan dlaam penelitian ini adalah kepiting bakau (Scylla sp) yang berasal dari pengepul yang diambil dari alam ukuran 90-100 g berasal dari daerah Bombana, Sulawesi Tenggara. Pemeliharaan hewan uji yang disiapkan adalah kontainer berukuran panjang 30 cm, lebar 16 cm dan tinggi 12 cm sebanyak 25 unit untuk satu perlakuan yang disusun dalam rak bertingkat. Rancangan penelitian yang digunakan adalah rancangan acak lengkap (RAL) 3 perlakuan dan 25 kali ulangan dan deskripsi. Hasil analisis ragam menunjukan bahwa ion Ca2+  berpengaruh nyata (P<0,05) terhadap struktural, pertubuhan dan FCR. Selain itu ion Ca2+ yang direspon oleh kepiting melalui mekanisme osmoregulasi yang mempengarugi penggunaan energi. Hilangnya energi yang mengarah pada semakin rendahnya pertumbuhan yang dicapai.

Kata Kunci : Ca2+, Kepiting bakau, mekanik, Pertumbuhan, Ultrastruktural
Design parameters affecting mechanical failure and electrochemical degradation of ultrathin Li-ion pouch cells under repeated flexing
Authors: Kim Kyungbae , Chan Candace K.
Published: March 2024

Understanding mechanical failure modes of Li-ion battery electrodes of varying sizes and capacities is crucially important for the development of mechanically robust and high energy density flexible lithium-ion batteries (FLIBs). Three types of pouch cells (nominal capacities of 15, 25, and 50 mAh) were examined to understand how various design features used in the cells affected their mechanical failure modes and electrochemical performance after repeated introduction of compression and tension during bending. Postmortem microstructure analysis was carried out to identify the impacts of repeated flexing; several failure modes such as crack propagation, particle detachment, composite delamination, separator damage, electrode tears, and micro-short circuits were observed. We find that the observed mechanical failure modes are mainly dependent on the: 1) size and shape of the electrode composite materials, 2) configuration of the components within the cell (e.g., method of electrode folding, location of welded tabs), and 3) orientation of the long axis of the cell with respect to the bending axis. It was observed that the discharge capacity for all cell types studied herein was only slightly decreased (∼6–7% at 2C-rate) even after 3,000 repeated bends at a 25 mm radius of curvature provided if the bending axis is aligned to the long dimension of the cell. The results of this study provide valuable information on possible failure modes in Li-ion battery electrodes subjected to repeated flexing and how they can be mitigated to improve the dependability of practical pouch cells for FLIBs.
Evaluation of novel compounds as anti-bacterial or anti-virulence agents
Authors: Filipić Brankica , Ušjak Dušan , Rambaher Martina Hrast , Oljacic Slavica , Milenković Marina T.
Published: March 2024

Antimicrobial resistance is a global threat, leading to an alarming increase in the prevalence of bacterial infections that can no longer be treated with available antibiotics. The World Health Organization estimates that by 2050 up to 10 million deaths per year could be associated with antimicrobial resistance, which would equal the annual number of cancer deaths worldwide. To overcome this emerging crisis, novel anti-bacterial compounds are urgently needed. There are two possible approaches in the fight against bacterial infections: a) targeting structures within bacterial cells, similar to existing antibiotics; and/or b) targeting virulence factors rather than bacterial growth. Here, for the first time, we provide a comprehensive overview of the key steps in the evaluation of potential new anti-bacterial and/or anti-virulence compounds. The methods described in this review include: a) in silico methods for the evaluation of novel compounds; b) anti-bacterial assays (MIC, MBC, Time-kill); b) anti-virulence assays (anti-biofilm, anti-quorum sensing, anti-adhesion); and c) evaluation of safety aspects (cytotoxicity assay and Ames test). Overall, we provide a detailed description of the methods that are an essential tool for chemists, computational chemists, microbiologists, and toxicologists in the evaluation of potential novel antimicrobial compounds. These methods are cost-effective and have high predictive value. They are widely used in preclinical studies to identify new molecular candidates, for further investigation in animal and human trials.
Variability in the drivers of microplastic consumption by fish across four lake ecosystems
Authors: Conowall Peter , Schreiner Kathryn M. , Marchand Joseph , Minor Elizabeth C. , Schoenebeck Casey W. , Maurer-Jones Melissa A. , Hrabik Thomas R.
Published: March 2024

Microplastic (<5 mm) pollution has been documented globally throughout freshwater and marine ecosystems. Exposure to and ingestion of microplastics presents a threat to the health of aquatic and marine organisms and humans through the consumption of fish and crustaceans. Understanding the factors which influence microplastic ingestion by fish is a key step in predicting the potential health risks. Drivers of microplastic consumption have been studied in lab settings, but there has been limited ability to confirm in field studies. Here we examine the roles and contributions of feeding guild, pelagic microplastic concentrations, and fish length to microplastic consumption by three species of fish across four lake ecosystems in Minnesota, United States. Fish samples were collected in the summers of 2019 and 2020 and processed to determine variability in microplastic ingestion. Identifying particles between 0.18 and 5 mm, plastic ingestion ranged from 0.6 microplastics fish−1 in Elk Lake (low surface water microplastics) bluegill to 1.09 microplastics fish-1 in White Iron Lake (moderate surface water microplastics) cisco. Results indicate that microplastic consumption by filter feeding cisco is driven by surface water microplastic concentrations, while microplastic consumption by visual feeding bluegill and yellow perch is not. Additionally, the high variability of ingestion between lake ecosystems coupled with the complex behavior of some fish species presents difficulties in identifying primary drivers of microplastic consumption that would be broadly applicable across ecosystems and species.
Holocene flood records and human impacts implied from the pollen evidence in the Daming area, North China Plain
Authors: Yang Jinsong , Liu Linjing , Roberts Harry , Liu Zhe , Song Lei , Zhang Peng
Published: March 2024

Understanding the environmental significance of pollen and spores in alluvial plains is important for stratigraphic correlation and paleoenvironmental reconstruction. This paper presents palynological data from the North China Plain and explores their relationship with paleoflood records and human impacts since the Holocene. Our data reveal that pollen concentration and pollen assemblage vary in flood deposits (including overbank deposits and slackwater deposits) and inter-flood deposits (including sandy soils and lacustrine deposits). Flood deposits have higher fern percentages (28.6%) and lower herbaceous percentages (14.8%) compared to inter-flood deposits, though slackwater deposits share similar pollen concentrations and assemblages with sandy soils. Notably, overbank deposits are characterized by pollen-poor zones and aggregation of deteriorated pollen grains, especially in Unit III (755–385 cm, ca. 3.2–2.2 ka) and Unit V (190–0 cm, after ca. 0.6 ka). These findings suggest that overbank deposits correspond to strengthened hydrodynamic conditions at the flood-peak stage. Furthermore, the indicative pollen and spores provide compelling evidence for intensifying human impact in the North China Plain since the late Holocene. An aggregation of Selaginella sinensis at the depth of 640–610 cm indicates deforestation in the uplands since ca. 2.9 ka. Similarly, a sharp increase in Malvaceae percentage at the depth of 285–215 supports historical records of initial cotton planting in the Tang Dynasty (ca. 1.4–1.1 ka). The study underscores the value of palynological analysis for reconstructing paleoenvironment and human-environment interactions, providing a robust framework for understanding landscape evolution in the North China Plain.
Polar low research: recent developments and promising courses of research
Authors: Moreno-Ibáñez Marta
Published: March 2024

Polar lows (PLs) are intense maritime mesoscale weather systems that develop during marine cold air outbreaks at high latitudes. The objective of this review is to describe the advances in polar low research since the last literature review—published 3 years ago—, indicate the knowledge gaps that remain, and suggest promising courses of research. Among the breakthroughs identified here are the first climatology of PLs obtained with a global atmospheric model, and increased evidence showing that baroclinic instability is the main mechanism leading to PL development. Despite these advances, many challenges persist such as the lack of conventional observations of PLs and the need to better understand coupled atmosphere-ocean processes involved in PL development. With the rapid advances in deep learning, this method has the potential to be used for PL forecasting.
Psychometric properties of the reading self-efficacy scale in Peruvian students aged 10 to 16 years
Authors: Morales-García Wilter C. , Muñante-Subauste Yovanna Ysabel , Sairitupa Sanchez Liset Z. , Morales-García Sandra B. , Rivera-Lozada Oriana , Cunza Aranzábal Denis Frank
Published: March 2024

Background

Reading self-efficacy is a key factor for students’ academic performance and motivation and given the low reading performance of Peruvian students compared to the average, it is crucial to understand and improve their reading self-efficacy.

Objective

To evaluate the psychometric properties of the Reading Self-Efficacy Scale in a Peruvian sample.

Methodology

Using a sample of 560 students aged 10 to 16 (M = 13.5, SD = 1.93), confirmatory factor analysis (CFA) and gender-specific invariance analysis were conducted.

Results

A two-dimensional, second-order model was taken into consideration. Significant differences were discovered in gender invariance, suggesting that the scale is comparable between the genders.

Conclusion

The validation of the Reading Self-Efficacy Scale in the Peruvian context provides a useful tool to assess and develop Peruvian students’ reading self-efficacy, with implications for professional practice and educational policy.
An analytical method for free vibrations of the fuel rod with non-uniform mass of small modular reactor
Authors: Yang Guowei , Zhang Yong , Fan Tiandi , Song Yong , Bai Yunqing
Published: March 2024

The intricate internal structure of fuel rods results in a non-uniform mass distribution, making it imperative to employ analytical methods for accurate assessment. The study utilizes Euler beam theory to derive the transverse vibration equation for beams with varying mass distribution. The approach involves transforming the non-uniform mass beam into a multi-segment beam with concentrated mass points. Modal function relationships between adjacent uniform segments are established based on continuous conditions at connection points. This transformation leads to the conversion of the variable coefficient differential equation into a nonlinear matrix equation. The Newton-Raphson method is then applied to calculate the characteristic equation and mode shapes, essential for determining natural frequencies. To validate precision, the results obtained are compared with those derived from the finite element method. Furthermore, the developed method is employed to assess the impact of gas plenum location and length on the natural frequency of fuel rods. The proposed methodology serves as a rapid design tool, particularly beneficial during the design phase of fuel rods with non-uniform mass distribution, aiding in configuring structural aspects effectively.
Identification of a novel KCNT2 variant in a family with developmental and epileptic encephalopathies: a case report and literature review
Authors: Cui Fengji , Wulan Tuoya , Zhang Qian , Zhang Victor Wei , Jiang Yuhua
Published: March 2024

Background: Developmental and epileptic encephalopathies (DEEs) are a group of heterogeneous neurodevelopmental diseases characterized mainly by developmental delay/intellectual disability and early-onset epilepsy. Researchers have identified variations in the KCNT2 gene (OMIM* 610044) as the cause of DEE type 57 (MIM# 617771).

Case presentation: We report in this study a 46-year-old woman who presented with early-onset epilepsy, intellectual disability, hypertrichosis, coarse facial features, and short stature. Besides, there were four other affected individuals in her family history, including two elder brothers, a younger brother, and their mother. We collected blood samples from the proband, her two affected brothers, and her clinically normal daughter for genetic analysis. Clinical exome sequencing revealed a novel heterozygous variant in the KCNT2 gene (NM_198503: c.188G>A, p.Arg63His) in the proband and her two affected brothers, while her daughter did not carry this variant. Furthermore, we reviewed all 25 patients identified in the literature with KCNT2 variants and compared their phenotypes.

Conclusion: Epilepsy and intellectual disability/developmental delay occur in almost all patients with KCNT2 variants. KCNT2-relevant DEEs partially overlap with the clinical phenotypes of KATP channel diseases, particularly in hypertrichosis and distinctive coarse facial features.
Antibody dependent cellular cytotoxicity-inducing anti-EGFR antibodies as effective therapeutic option for cutaneous melanoma resistant to BRAF inhibitors
Authors: Muraro Elena , Montico Barbara , Lum Benedict , Colizzi Francesca , Giurato Giorgio , Salvati Annamaria , Guerrieri Roberto , Rizzo Aurora , Comaro Elisa , Canzonieri Vincenzo , Anichini Andrea , Del Vecchio Michele , Mortarini Roberta , Milione Massimo , Weisz Alessandro , Pizzichetta Maria Antonietta , Simpson Fiona , Dolcetti Riccardo , Fratta Elisabetta , Sigalotti Luca
Published: March 2024

Introduction

About 50% of cutaneous melanoma (CM) patients present activating BRAF mutations that can be effectively targeted by BRAF inhibitors (BRAFi). However, 20% of CM patients exhibit intrinsic drug resistance to BRAFi, while most of the others develop adaptive resistance over time. The mechanisms involved in BRAFi resistance are disparate and globally seem to rewire the cellular signaling profile by up-regulating different receptor tyrosine kinases (RTKs), such as the epidermal growth factor receptor (EGFR). RTKs inhibitors have not clearly demonstrated anti-tumor activity in BRAFi resistant models. To overcome this issue, we wondered whether the shared up-regulated RTK phenotype associated with BRAFi resistance could be exploited by using immune weapons as the antibody-dependent cell cytotoxicity (ADCC)-mediated effect of anti-RTKs antibodies, and kill tumor cells independently from the mechanistic roots.

Methods and results

By using an in vitro model of BRAFi resistance, we detected increased membrane expression of EGFR, both at mRNA and protein level in 4 out of 9 BRAFi-resistant (VR) CM cultures as compared to their parental sensitive cells. Increased EGFR phosphorylation and AKT activation were observed in the VR CM cultures. EGFR signaling appeared dispensable for maintaining resistance, since small molecule-, antibody- and CRISPR-targeting of EGFR did not restore sensitivity of VR cells to BRAFi. Importantly, immune-targeting of EGFR by the anti-EGFR antibody cetuximab efficiently and specifically killed EGFR-expressing VR CM cells, both in vitro and in humanized mouse models in vivo, triggering ADCC by healthy donors’ and patients’ peripheral blood cells.

Conclusion

Our data demonstrate the efficacy of immune targeting of RTKs expressed by CM relapsing on BRAFi, providing the proof-of-concept supporting the assessment of anti-RTK antibodies in combination therapies in this setting. This strategy might be expected to concomitantly trigger the crosstalk of adaptive immune response leading to a complementing T cell immune rejection of tumors.
The self-reactive FVIII T cell repertoire in healthy individuals relies on a short set of epitopes and public clonotypes
Authors: Porcheddu Valeria , Lhomme Gautier , Giraudet Rémi , Correia Evelyne , Maillère Bernard
Published: March 2024

Non-mutated FVIII-specific CD4 T cell epitopes have been recently found to contribute to the development of inhibitors in patients with hemophilia A (HA), while auto-reactive CD4 T cells specific to FVIII circulate in the blood of healthy individuals at a frequency close to the foreign protein ovalbumin. Thus, although FVIII is a self-protein, the central tolerance raised against FVIII appears to be low. In this study, we conducted a comprehensive analysis of the FVIII CD4 T cell repertoire in 29 healthy donors. Sequencing of the CDR3β TCR region from isolated FVIII-specific CD4 T cells revealed a limited usage and pairing of TRBV and TRBJ genes as well as a mostly hydrophobic composition of the CDR3β region according to their auto-reactivity. The FVIII repertoire is dominated by a few clonotypes, with only 13 clonotypes accounting for half of the FVIII response. Through a large-scale epitope mapping of the full-length FVIII sequence, we identified 18 immunodominant epitopes located in the A1, A3, C1, and C2 domains and covering half of the T cell response. These epitopes exhibited a broad specificity for HLA-DR or DP molecules or both. T cell priming with this reduced set of peptides revealed that highly expanded clonotypes specific to these epitopes were responsible individually for up to 32% of the total FVIII repertoire. These FVIII T cell epitopes and clonotypes were shared among HLA-unrelated donors tested and previously reported HA patients. Our study highlights the role of the auto-reactive T cell response against FVIII in HA and its similarity to the response observed in healthy individuals. Thus, it provides valuable insights for the development of new tolerance induction and deimmunization strategies.
The impact and relevance of techniques and fluids on lung injury in machine perfusion of lungs
Authors: Ponholzer Florian , Dumfarth Julia , Krapf Christoph , Pircher Andreas , Hautz Theresa , Wolf Dominik , Augustin Florian , Schneeberger Stefan
Published: March 2024

Primary graft dysfunction (PGD) is a common complication after lung transplantation. A plethora of contributing factors are known and assessment of donor lung function prior to organ retrieval is mandatory for determination of lung quality. Specialized centers increasingly perform ex vivo lung perfusion (EVLP) to further assess lung functionality and improve and extend lung preservation with the aim to increase lung utilization. EVLP can be performed following different protocols. The impact of the individual EVLP parameters on PGD development, organ function and postoperative outcome remains to be fully investigated. The variables relate to the engineering and function of the respective perfusion devices, such as the type of pump used, functional, like ventilation modes or physiological (e.g. perfusion solutions). This review reflects on the individual technical and fluid components relevant to EVLP and their respective impact on inflammatory response and outcome. We discuss key components of EVLP protocols and options for further improvement of EVLP in regard to PGD. This review offers an overview of available options for centers establishing an EVLP program and for researchers looking for ways to adapt existing protocols.
Case report: Rapid recovery after intrathecal rituximab administration in refractory anti-NMDA receptor encephalitis: report of two cases
Authors: Reda Mahasen , Jabbour Rosette , Haydar Asad , Jaafar Fatima , El Ayoubi Nabil , Nawfal Omar , Beydoun Ahmad
Published: March 2024

Background

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is one of the most prevalent etiologies of autoimmune encephalitis. Approximately 25% of anti-NMDAR encephalitis cases prove refractory to both first- and second-line treatments, posing a therapeutic dilemma due to the scarcity of evidence-based data for informed decision-making. Intravenous rituximab is commonly administered as a second-line agent; however, the efficacy of its intrathecal administration has rarely been reported.

Case summary

We report two cases of severe anti-NMDAR encephalitis refractory to conventional therapies. These patients presented with acute-onset psychosis progressing to a fulminant picture of encephalitis manifesting with seizures, dyskinesia, and dysautonomia refractory to early initiation of first- and second-line therapeutic agents. Both patients received 25 mg of rituximab administered intrathecally, repeated weekly for a total of four doses, with no reported adverse effects. Improvement began 2–3 days after the first intrathecal administration, leading to a dramatic recovery in clinical status and functional performance. At the last follow-up of 6 months, both patients remain in remission without the need for maintenance immunosuppression.

Conclusion

Our cases provide evidence supporting the intrathecal administration of rituximab as a therapeutic option for patients with refractory anti-NMDAR encephalitis. Considering the limited penetration of intravenous rituximab into the central nervous system, a plausible argument can be made favoring intrathecal administration as the preferred route or the simultaneous administration of intravenous and intrathecal rituximab. This proposition warrants thorough investigation in subsequent clinical trials.
Ocean-driven interannual variability in atmospheric CO2 quantified using OCO-2 observations and atmospheric transport simulations
Authors: Guan Yifan , McKinley Galen A. , Fay Amanda R. , Doney Scott C. , Keppel-Aleks Gretchen
Published: March 2024

Interannual variability (IAV) in the atmospheric CO2 growth rate is caused by variation in the balance between uptake by land and ocean and accumulation of anthropogenic emissions in the atmosphere. While variations in terrestrial fluxes are thought to drive most of the observed atmospheric CO2 IAV, the ability to characterize ocean impacts has been limited by the fact that most sites in the surface CO2 monitoring network are located on coasts or islands or within the continental interior. NASA’s Orbiting Carbon-Observatory 2 (OCO-2) mission has observed the atmospheric total column carbon dioxide mole fraction (XCO2) from space since September 2014. With a near-global coverage, this dataset provides a first opportunity to directly observe IAV in atmospheric CO2 over remote ocean regions. We assess the impact of ocean flux IAV on the OCO-2 record using atmospheric transport simulations with underlying gridded air-sea CO2 fluxes from observation-based products. We use three observation-based products to bracket the likely range of ocean air-sea flux contributions to XCO2 variability (over both land and ocean) within the GEOS-Chem atmospheric transport model. We find that the magnitude of XCO2 IAV generated by the whole ocean is between 0.08-0.12 ppm throughout the world. Depending on location and flux product, between 20-80% of the IAV in the simulations is caused by IAV in air-sea CO2 fluxes, with the remainder due to IAV in atmospheric winds, which modulate the atmospheric gradients that arise from climatological ocean fluxes. The Southern Hemisphere mid-latitudes and low-latitudes are the dominant ocean regions in generating the XCO2 IAV globally. The simulation results based on all three flux products show that even within the Northern Hemisphere atmosphere, Southern Hemisphere ocean fluxes are the dominant source of variability in XCO2. Nevertheless, the small magnitude of the air-sea flux impacts on XCO2 presents a substantial challenge for detection of ocean-driven IAV from OCO-2. Although the IAV amplitude arising from ocean fluxes and transport is 20 to 50% of the total observed XCO2 IAV amplitude of 0.4 to 1.6 ppm in the Southern Hemisphere and the tropics, ocean-driven IAV represents only 10% of the observed amplitude in the Northern Hemisphere. We find that for all three products, the simulated ocean-driven XCO2 IAV is weakly anti-correlated with OCO-2 observations, although these correlations are not statistically significant (p>0.05), suggesting that even over ocean basins, terrestrial IAV obscures the ocean signal.
Comparing the underwater soundscape of the Hawaiian Islands Humpback Whale National Marine Sanctuary and potential influences of the COVID-19 pandemic
Authors: Madrigal Brijonnay C. , Kügler Anke , Zang Eden J. , Lammers Marc O. , Hatch Leila T. , Pacini Aude F.
Published: March 2024

Passive acoustic monitoring is an effective technique for long-term monitoring of the soundscape in marine protected areas. Ocean noise is a key concern for the U.S. Office of National Marine Sanctuaries and has been identified as a research priority. The Sanctuary Soundscape Monitoring Project (“SanctSound”) was implemented to support efforts to address ocean noise across seven U.S. sanctuaries using a comprehensive and standardized approach. In this study, acoustic recordings were collected in the Hawaiian Islands Humpback Whale National Marine Sanctuary during the humpback whale seasons (November-May) from 2018-2022. Data encompassed 14 deployments across four sites in the main Hawaiian Islands: Hawaiʻi, Maui, O’ahu, and Kauaʻi. The soundscape was dominated by biological sources, most prominently the seasonal detection of humpback whale song. Third octave level monthly medians ranged from 70.4-105 dB re 1 µPa across sites with distinct peaks from January to April particularly at both Hawaiʻi and Maui sites. Overall, we reported relatively low vessel detection rates, with Maui having the highest daily average of vessel detections (x = 19.16). No COVID-19 impact could be observed acoustically using soundscape metrics which was likely due to the dominance of humpback whale chorusing. However, vessel detections and AIS data revealed a reduction in vessel activity after the onset of the pandemic at the Maui and Hawaiʻi sites. This study demonstrates that standardized metrics are a useful tool for obtaining long-term, baseline soundscape levels to understand the various contributions to the underwater soundscape and potential changes within marine protected areas in Hawaiʻi.
Thermal transport of glasses via machine learning driven simulations
Authors: Pegolo Paolo , Grasselli Federico
Published: March 2024

Accessing the thermal transport properties of glasses is a major issue for the design of production strategies of glass industry, as well as for the plethora of applications and devices where glasses are employed. From the computational standpoint, the chemical and morphological complexity of glasses calls for atomistic simulations where the interatomic potentials are able to capture the variety of local environments, composition, and (dis)order that typically characterize glassy phases. Machine-learning potentials (MLPs) are emerging as a valid alternative to computationally expensive ab initio simulations, inevitably run on very small samples which cannot account for disorder at different scales, as well as to empirical force fields, fast but often reliable only in a narrow portion of the thermodynamic and composition phase diagrams. In this article, we make the point on the use of MLPs to compute the thermal conductivity of glasses, through a review of recent theoretical and computational tools and a series of numerical applications on vitreous silica and vitreous silicon, both pure and intercalated with lithium.
Risk of adverse perinatal outcomes among women with clinical and subclinical histopathological chorioamnionitis
Authors: Olguín-Ortega Andrea , Figueroa-Damian Ricardo , Palafox-Vargas Martha Leticia , Reyes-Muñoz Enrique
Published: March 2024

Introduction

Histologic chorioamnionitis (HCA) is a placental inflammatory condition associated with adverse perinatal outcomes (APOs). This historical cohort study explores the risk of APOs in pregnant women with HCA and compares the impact of clinical chorioamnionitis (CCA) with subclinical chorioamnionitis (SCCA).

Methodology

Placentas were evaluated by a perinatal pathologist tand all women with HCA were included. Two groups were integrated: (1) women with clinical chorioamnionitis (CCA) and (2) women with subclinical chorioamnionitis (SCCA). Additionally, we conducted a secondary analysis to compare the prevalence of APOs among stage 1, 2 and 3 of HCA and the risk of APOs between grades 1 and 2 of HCA. The APOs analyzed were preterm birth, stillbirth, neonatal weight < 1,500 g, neonatal sepsis. Relative risk with 95% confidence interval was calculated.

Results

The study included 41 cases of CCA and 270 cases of SCCA. The mean gestational age at diagnosis and birth was 30.2 ± 5.4 weeks and 32.5 ± 5.1 weeks, for group 1 and 2, respectively. The study also found that women with HCA stage 3 and grade 2 had a higher prevalence and risk of adverse perinatal outcomes.

Discussion

The findings of this study suggest the importance of placental histological study to excluded SCCA, which represents a significant risk to both maternal and neonatal health, contributing to high morbidity and mortality.
Antimicrobial treatment in invasive infections caused by Gordonia bronchialis: systematic review
Authors: Zivkovic Zaric Radica , Canovic Petar , Zaric Milan , Vuleta Marko , Vuleta Nedic Katarina , Jovanovic Jovan , Zornic Nenad , Nesic Jelena , Spasic Marko , Jakovljevic Stefan , Ilic Milena , Jovanovic Dalibor , Todorovic Zeljko , Arsenijevic Petar , Sovrlic Miroslav , Milovanovic Jasmina
Published: March 2024

Background

Corynebacterium, Nocardia, Rhodococcus, Mycobacterium, as well as Gordonia genera belongs to the genus Gordonia, Actinomycetia class. Gordonia bronchialis is a nitrate-reducing, urease-producing, non-motile, force aerobe with a rod-like figure that is known to arrangement into sessile, cord-like groups. This systematic review aimed to establish whether and what invasive infections in humans were caused by Gordonia bronchialis, and to evaluate outcomes of administered antibiotic treatment.

Methods

We have registered this systematic review in PROSPERO database of systematic reviews and meta-analyses with the number CRD42022369974.

Results

A total of 24 publications were included (22 case reports and two case series) with 28 individual cases. The oldest patients had 92 years, and the youngest patients had 13 years. Clinical signs of infection were present in six patients (21%). All isolates were susceptible to ciprofloxacin, imipenem, and amikacin. Vancomycin was the most frequently used antibiotic with nine cases followed by ciprofloxacin, ceftriaxone, and amoxicillin/clavulanic acid.

Conclusion

Although there are no standardized recommendations to date, successful treatment with a favorable outcome has most often been carried out with fluoroquinolones, vancomycin with or without aminoglycosides, as well as carbapenems.