bluuebunny/crossref_metadata_2025 huggingface dataset:
One-pot determination of amino acids in drugs by pre-column derivatization with phenyl isothiocyanate
Authors: Kalmykov P. A. , Kustova T P. , Kustov S. O. , Shestakovskaya P. S. , Azmetov T. R. , Kalmykova A. A.
Published: May 2024

Objectives. To develop a new method to determine amino acids in drugs by means of reverse-phase high-performance chromatography (RP HPLC) with pre-column derivatization using phenyl isothiocyanate (PITC) and one-pot sample preparation.

Methods. The initial standard solutions of amino acids were prepared by weighing, followed by dissolution in water. Working solutions were then prepared: standard, test, and blank, by dilution in 20 mM hydrochloric acid. Further sample preparation was carried out in Safe-lock polypropylene tubes (Eppendorf) in a reaction buff containing mobile phase A, acetonitrile, and triethylamine in a ratio of 85 : 10 : 5, labeled with a 5% PITC solution in acetonitrile. After thorough mixing for 3–5 min on a vortex, the tubes were kept in a solid-state thermostat with a thermally insulating lid for 2 h. The samples were then cooled for 10 min, centrifuged for 1 min at 13000 rpm, the supernatant was transferred into vials, and the mixture of amino acids was separated by RP HPLC using hydrophobic silica gel with grafted C18 groups as a stationary phase. The quantitative determination of amino acid derivatives was carried out using a diode array detector.

Results. A new method for the separation and determination of amino acids in medicinal preparations was developed and validated. Simple one-pot sample preparation using available reagents and equipment enabled studies to be carried out without using commercial kits, for example, the AccQ.Tag Ultra Derivatization Kit, USA. Using the analysis of mixtures of histidine and glycine as an example, it was shown that when using two mobile phases, an acceptable separation of amino acid derivatives in a gradient mode can be achieved for 20 min at a flow rate of 1.0 mL/min. The samples prepared according to the new method demonstrated a high level of stability in use and storage. A composition of mobile phases A and B consisting of 10 mM acetate buffer pH 3.5 and 80% acetonitrile solution was proposed. Validation of the method hereby developed in the analysis of the drug Innonafactor®, containing glycine and histidine as excipients, demonstrated high convergence of the results of the quantitative determination of these amino acids.

Conclusions. The new method to determine amino acids in medicinal preparations by RP HPLC with PITC pre-column derivatization has a wide range of applications, has a number of advantages when compared to imported commercial kits for the determination of amino acids. These include: lower cost of reagents and materials, high accuracy and repeatability. Thus, it can be recommended for use in quality control laboratories of pharmaceutical enterprises.
Natural and synthetic isoprene rubbers obtained using Ziegler–Natta catalysts
Authors: Zuev A. A. , Zolotarev V. L. , Levenberg I. P. , Kovaleva L. A. , Nasyrov I. Sh.
Published: May 2024

Objectives. To compare the properties of rubber compounds and rubbers based on natural rubber RSS1 and synthetic isoprene rubbers obtained using Ti, Nd, Gd catalysts, both when used individually in the formulation of rubber compounds and when synthetic analogues partially replace natural rubber.

Methods. Rubber compounds were prepared using a laboratory roll and a 100 cm3 rubber mixer. For rubber compounds, the following factors were determined: Mooney viscosity, cohesive strength, and vulcanization characteristics. For rubbers, the following factors were determined: physical and mechanical parameters, Shore A hardness, rebound resilience, and volume loss upon abrasion.

Results. Based on the results of the rubber compound tests, the study showed that compounds based on all the synthetic polyisoprenes studied are significantly inferior to compounds based on natural rubber in terms of cohesive strength. The partial replacement of natural rubber with synthetic rubber (regardless of the type of catalytic system) leads to a significant decrease in the cohesive strength of the blends. Despite the differences observed in the properties of the rubber compounds, the results of the rubbers based on individual rubbers do not manifest significant differences.

Conclusions. The study demonstrated the influence of defects (oligomers, gel, low molecular weight fractions, branches, and 3,4-units) in the structure of synthetic polyisoprenes on the cohesive strength index of rubber compounds based on them, in which the number of 3,4-units plays a decisive role. The study also showed the potential of studying synthetic polyisoprenes as analogues of natural rubber in formulations of rubber compounds in the aims of resolving the problem of import substitution in the tire and rubber goods industry.
Regulatory Compliance of PCDD/F Emissions by a Municipal Solid Waste Incinerator: A Case Study in Sant Adrià de Besòs, Catalonia, Spain
Authors: Domingo Jose L , Nadal Marti , Rovira Joaquim
Published: May 2024

Despite incineration being an important emission source of toxic pollutants, such as heavy metals and polychlorinated dibenzo_-p-_dioxins and dibenzofurans (PCDD/Fs), it is still one of the most widely used methods for the management of municipal solid waste. The current paper summarizes the results of a follow-up study of the emissions of PCDD/Fs by the municipal solid waste incinerator (MSWI) of Sant Adrià de Besòs (Catalonia, Spain), which was conducted in our laboratory for 20 years. Samples of air, soils, and herbage were periodically collected near the facility, and the content of PCDD/Fs was analyzed. In our last (2017) survey, mean levels in soil were 3.60 ng WHO-TEQ/kg (range: 0.40-10.6), considerably higher than the mean concentrations of PCDD/Fs in soil samples collected near other MSWIs in Catalonia. Moreover, air PCDD/F concentrations were even higher than those found in a previous (2014) survey, as they increased from 0.026 to 0.044 pg WHO-TEQ/m3. Ultimately, the PCDD/F exposure would be associated with a cancer risk (2.5 x 10-6) for the population living in the surrounding area. Globally, this information indicates that the MSWI of Sant Adrià de Besòs could have had a negative impact on the environment and also potentially on public health, being an example of possible inappropriate management for years.
Human and Environmental Factors Shape Tree Species Assemblages in West African Tropical Forests
Authors: Asuk Sijeh Agbor , Wayman Joseph P. , Sadler Jonathan P. , Pugh Thomas A. M. , Matthews Thomas J. , Ebu Vincent T. , Phillips Oliver L. , Lewis Simon , Sonké Bonaventure , Talbot Joey , Comiskey James , Zemagho Lise , Ojo Lucas , Begne Serge , Taedoumg Hermann , Sunderland Terry , Hubau Wannes , Droissart Vincent , Qie Lan , Gilpin Martin B. , Simo-Droissart Murielle , Feldpausch Ted R. , Peh Kelvin S. H. , Banin Lindsay F., , Kamdem Marie Noel Djuikouo , Kettridge Nicholas
Published: May 2024

Human activities exert a pronounced influence on forest ecosystems, impacting both biodiversity and function across multiple scales. Despite this, the consequences of low-intensity human activities on tropical forest ecosystems are difficult to assess and, therefore, remain poorly explored. Here, the influence of human activities and other site-specific variables on forest tree assemblages in central-west Africa was investigated. By dividing forest tree species into edible (from the perspective of humans) and inedible species, we aimed to assess the differential impacts of human resource use on different species; in particular, the greatest impact of human activity was expected to be seen on edible tree species. Tree data from 66 plots across Nigeria and Cameroon collected between 2002 and 2019 and Generalized Dissimilarity Models (GDMs) were used to assess pairwise beta-diversity between plots, accounting for candidate factors including proximity to human presence, elevation, and stem density. The analysis revealed that human activity significantly affects beta-diversity within the Nigeria-Cameroon forest region. The key variables that shape total beta-diversity included geographical distance between plots, plot elevation, stem density, proximity to human presence, and forest species composition. The forest species composition (monodominant or mixed forest) appeared to influence dissimilarity in beta-diversity, specifically for edible tree species. This pattern was not observed for inedible species, likely linked to the cultural practices in the region. While stem density contributed to the edible species models, elevation was more relevant for inedible species. These findings underscore the critical role of human influence in shaping tree species assemblages in African tropical forests and stress the necessity for further research in this area.
Spatially Weighted Multinomial Modelling of Comorbidity of Anaemia and Malaria among Under Five Children in Nigeria
Authors: Ibrahim Aminu , Adeyemi Rasheed A. , Usman Abubakar , Adabara Nasiru Usman
Published: May 2024

Children in sub-Saharan African countries especially Nigeria continue to suffer increased mortality owing to comorbidity of infections such as anaemia and malaria, which are known to epidemiologically overlap. In order to examine the risk factors and spatial patterns of comorbidity of anaemia and malaria using 2021 Nigeria malaria indicator survey (NMIS), multinomial logit model was extended by incorporating spatially weighted random effect. The impact of climatic variation on the childhood disease comorbidity was explored by weighting the spatial structured component based on the 2021 NMIS average cluster temperature of each state in Nigeria. A number of spatial weighted geo-additive models were fitted and compared using defiance information criterion. Inference was fully Bayesian and Intrinsic Conditional Autoregressive prior was used for structured random effects. Based on the map generated from the best- fitted model which unveiled states that are more susceptible to the risk of disease comorbidity, the average temperature used as a weighting factor however has strong relationship with the spatial pattern of disease comorbidity. States with low temperature have higher risk of comorbidity of anaemia and malaria compared to states with higher average temperature.Area of residence, level of education of the mother, economic status of the mother and owning mosquito-treated nets were identified as the significant risk factors associated with the disease comorbidity.Findings from this study will be helpful to policymakers and health authorities in their effort to combat the comorbidity of childhood anaemia and malaria thereby reducing child mortality in Nigeria.
Overt PRO in Gã
Authors: Allotey Deborah , Paul Ileana
Published: May 2024

This paper presents data from Gã (Kwa, Niger-Congo language spoken in Ghana) that show that controlled subjects of non-finite predicates must be overt in this language. The presence of an overt pronominal subject in a non-finite embedded clause is surprising from the perspective of languages such as English and French, where such subjects must be covert (PRO). We provide evidence that the overt pronoun in Gã patterns with obligatorily controlled PRO (Hornstein 1999; Landau 2013) and argue for the minimal pronoun analysis of Kratzer (2009).
causative construction in Likpakpaanl (Konkomba)
Authors: Bisilki Kwesi Abraham
Published: May 2024

This article is a contribution to the cross-linguistic discussion on causation. It proceeds on the note that causation is a significant notion, both cognitively and grammatically. I make a case that the Mabia (Gur) languages of West Africa are severely under-represented in the literature on causation. I then focus on causation in Likpakpaanl, an under-researched Mabia language spoken in Ghana and Togo in West Africa. I further present data from thirteen other related West African languages for comparative purposes. Broadly speaking, Likpakpaanl deploys all the traditional causation strategies- lexical, morphological, serialising and analytic. However, the use of nasals, especially vowel nasality as a causativisers is novel and uniquely places Likpakpaanl among its linguistic relatives. The Likpakpaanl analytic causative marker chà has a functional scope for both factitive and permissive causatives. In a sense, the source of the specialised analytic causative marker in Likpakpaanl diverges from the oft-cited cross-linguistic source of analytic causative markers. The Likpakpaanl biclausal causative is the balanced structure and, therefore, aligns well with the biclausal causative structure described for the West African linguistic area, contra the deraked structure of Indo-European languages. A thorough investigation of the constellation of causatives in Mabia promises new insights into causative typology.
Grammaticalization in Fanakalo: simplification, complexification, and acceleration
Authors: Andrason Alexander
Published: May 2024

The present article studies the structure of the resultative stream (a part of the verbal system that hosts grams diachronically evolving along and synchronically modelled by means of the resultative path: resultative > perfect > perfective/past and resultative > stative > present) in the Fanakalo pidgin as compared to the lexifier Nguni languages (Zulu/Xhosa). The evidence indicates that the organization of the resultative stream in Fanakalo is different from that found in Nguni, attesting to both simplification and complexification, as well as the acceleration of the movement along the resultative path and the cline of structural grammaticalization. This corroborates the views concerning the increase in complexity of stabilized and expanded pidgins and the observation suggesting the acceleration of grammaticalization processes in a situation of contact.
Organize Sanayi Bölgeleri’nin Natech Riskine Göre Değerlendirilmesi: Kocaeli İli İçin Bir Örnek
Authors: Güven Emel , Pınarbaşı Mehmet , Alakaş Hacı Mehmet , Eren Tamer
Published: May 2024

Afetler günlük hayatın akışını etkileyen doğa olaylarıdır. Doğal afetler sonucunda canlı ve cansız varlıklar için maddi ve manevi olarak ciddi hasarlar ortaya çıkmaktadır. Oluşan hasarların yanı sıra bazı zamanlarda afetler tarafından tetiklenen teknolojik kazalar da meydana gelmektedir. Doğal afetlerin tetiklediği teknolojik kazalar Natech kazaları olarak adlandırılmaktadır. Natech kazaları, afetlerin gerisinde kalmış olsa da Türkiye’de 6 Şubat 2023 tarihinde gerçekleşen Kahramanmaraş merkezli deprem sonrası yeniden gündeme gelmiştir. Deprem sonrası İskenderun yat limanında çıkan yangının söndürülmesi için ciddi uğraşlar verilmiştir. Bu olay Natech kazası olarak kayıtlara geçmiştir. 10 Eylül 2023 tarihinde Libya’da meydana gelen selde barajların yıkılması afetin zararını çok daha ciddi boyutlara taşımıştır. Natech kazaları endüstriyel kuruluşlar için de önemli bir risk faktörü oluşturmaktadır. Bu kapsamda bünyesinde birden fazla sektörde hizmet veren endüstriyel kuruluş bulunan Organize Sanayi Bölgeleri (OSB), Natech kazaları açısından riskli bir konumdadır. Bu çalışmada Kuzey Anadolu fay hattı üzerinde 12 OSB’si bulunan Kocaeli ilinde bir uygulama gerçekleştirilmiştir. Literatür taraması ile belirlenen Natech kriterleri doğrultusunda Kocaeli’nde yer alan OSB’ler Natech riskine göre değerlendirilmiştir. Natech kriterlerinin değerlendirilmesinde Pisagor Bulanık AHP (Analitik Hiyerarşi Yöntemi), OSB’lerde bulunan sektörlerin sıralanmasında ise Pisagor Bulanık TOPSIS (Technique for Order Preference by Similarity) yöntemi kullanılmıştır. Çalışma ortamındaki verilerin deterministik yapıda olmaması ve belirsizliklerin bulunması sebebiyle ele alınan problemde bulanık kümeler ile çözüm elde edilmiştir.
Data-Driven Decision Making in Scholarship Programs: Leveraging Decision Trees and Clustering Algorithms
Authors: Espiritu Fokker V. , Natividad Marvee Cheska B. , Velasco Rosemary A.
Published: May 2024

This study presents a unique and innovative approach to improving the management of scholarship programs through the integration of data mining techniques and online systems. The BRO-Ed Scholarship program in Isabela province is facing the challenge of efficiently handling a growing number of scholarship applications. This study involves leveraging data mining to simplify this process, address operational challenges, and contribute to the transformation of the lives of underprivileged students. Data mining techniques that include systematic data integration, preprocessing, decision tree implementation, and clustering algorithms were utilized in this study. Additionally, we have created a user-friendly online platform to enhance accessibility. Initial results show a significant increase in the success rate, indicating the potential of managing scholarships using data-driven approaches. The expected outcomes include a streamlined application process, informed decisions based on data-driven analysis, and optimized budget allocation. By establishing a model for innovative advancement in scholarship programs, this project aims to promote educational support initiatives for underprivileged students aligned with the government’s mandate for Sustainable Development Goal 4, addressing growing inequality among marginalized people and communities.
Keywords: Data Mining, Decision Trees, Clustering Algorithm, Scholarship Programs, Underprivileged Students, Sustainable Development Goal 4
 
Received Date: March 2, 2024Revised Date: April 22, 2024Accepted Date: May 4, 2024
Relationship of calcium and phosphorus content with indicators of reproductive ability in cattle
Authors: Klimkovetskaya L. V. , Karpovskyi V. I. , Gutyj B. V. , Hryshchuk I. A.
Published: May 2024

The development of modern animal husbandry is quite an urgent issue today, because the consumption of dairy and meat products is growing rapidly. Factors affecting reproducibility play a key role in this issue. The aim of the work was to investigate the dependence of the content of calcium and phosphorus in blood serum with indicators of reproductive ability in cows. A spectrophotometer was used to study calcium and phosphorus content. A correlation dependence of the calcium content with the insemination index was established, which is a moderate positive correlation r = 0.494 (Р ≤ 0.001), with the service period – an average positive correlation r = 0.643 (Р ≤ 0.001) and days to the 1st heat – a strong positive correlation r = 0.862 (Р ≤ 0.001). Phosphorus content has an average positive correlation with the service period corresponding to r = 0.599 (Р ≤ 0.001), with the insemination index had the smallest correlation, which is r = 0.314 (Р ≤ 0.001) and the duration of days to the 1st mating has a very strong positive correlation, which is r = 0.909 (Р ≤ 0.001). Based on the obtained data, we can testify about the dependence of calcium and phosphorus content with indicators of reproducibility, such as insemination index, service period and days to the 1st heat. What gives reason for further research with the establishment of the interdependence of the reproducible ability during its correction from the side of influence on elements that have a correlation dependence with these indicators.
Chronic latent inflammatory processes of reproductive organs of dairy cows
Authors: Sidashova S. O. , Gutyj B. V. , Martyshuk T. V. , Shnaider V. L.
Published: May 2024

The purpose of a long-term scientific and industrial study was to determine the prevalence of the symptom complex of chronic inflammatory processes of the organs of the reproductive tract with latent flow among dairy cows (n = 1159) of various dairy breeds kept in the conditions of industrial complexes. Research methods. An innovative methodological approach of complex in vivo gynecological examination was applied using echography (“Tringa vet”) and differential palpation diagnostics with a recording of data on anatomical areas of the reproductive tract “walls and cavity of the uterus – horns of the uterus – fallopian tubes and their potential patency – ovaries”. Based on the results of a comprehensive examination of unfertilized dairy cows, it was established that, on average, chronic latent endometritis was diagnosed in 52.95 ± 12.96 % of females, with fluctuations of 32.15–85.84 % in different herds (P < 0.05). A natural trend of increasing cases of chronic adhesive processes with loss of patency for gametes through the fallopian tube in the tissues in the “fallopian tube-ovary” anatomical region due to the increase in the number of chronic latent endometritis in the herd, namely the average number of salpingitis and ovosalpingitis 13.26 ± 2.27, was established. %, fluctuations ranged from 9.2 to 18.27 %. The use of an innovative lateralized approach to the palpation diagnostics of chronic adhesive lesions of the oviducts allowed for improvement in the prognosis of the effectiveness of the therapy of chronic salpingitis provided that bilateral lesions were detected, which characterize the irreversible infertility of the cow (37.93 ± 9.35 % of cases among all examined cows). The application of differential palpation diagnostics of the ovaries with the use of in vivo data visualization revealed the spread of hypotrophic lesions of the ovaries together with the course of chronic inflammatory pathologies of the uterine tissues (latent endometritis): 54.69 ± 19.80 % of cows were diagnosed with significantly pronounced hypotrophic processes in the functional tissues of the gonads, and 34.87 ± 19.59 % had moderate lesions. Experimental studies have shown a reliable trend of correlations between the spread of chronic latent inflammatory processes in various parts of the reproductive tract of dairy cows and the growth of clinical manifestations of hypotrophic phenomena in ovarian tissues, which gradually lose their generative and hormone-secreting function due to a decrease in cell trophism. The study results showed the need for further comprehensive analysis of the clinical condition of the organs of the reproductive system of dairy cows in vivo conditions.
Waldorf school. Ex post facto case study
Authors: Herenčić Lea , Topolovčan Tomislav
Published: May 2024

The Waldorf school has existed for more than a hundred years. There are over athousand of Waldorf schools around the world. Due to its pedagogical and didacticfeatures and the ideas of the founder Rudolf Steiner, it is intriguing, both for parents and(non)experts. Since this is an alternative free school, it is epistemologically interestingto use a qualitative approach in reconstructing the biographies of adult former studentsof the Waldorf school. Therefore, the aim of the qualitative ex post facto research of thecase study was to examine and understand the role that the Waldorf school played onthe later formal education and lifestyle of former students, i.e., four adult siblings fromone family. It is evident that the Waldorf school has an impact on later educationin state schools as well as the lifestyle of former adult students. However, one shouldnot consider it superior nor inferior to other alternative or state schools. Therefore, itis justified to say that the Waldorf school, in its hundred years of existence, has beenpositively evaluated in practice. The established perspective of educational scienceswhich claims that there is no such thing as the best school and that school is powerful,but not omnipotent verifies the aforementioned statement. This paper presents anddiscusses the theoretical premises and results of the case study
Recognition of peer violence in school – a challenge for students and teachers
Authors: Zobec Katja , Hmelak Aljaž
Published: May 2024

This article explores peer violence in schools, emphasizing the role of school culture,teachers, and students in recognizing and addressing this issue. It defines peer violenceas any form of physical, psychological, sexual, material, or online violence where a childtargeted by the violence feels threatened. The article distinguishes between direct andindirect peer violence, addressing both physical and verbal aggression. It underscoresthe crucial role of teachers in creating a safe environment, recognizing signs of violence,and implementing preventive measures. The article emphasizes the importance of acomprehensive approach to problem-solving, involving students, aggressors, andbystanders while promoting a culture of zero tolerance for violence.
PENGARUH VARIASI DIMENSI SUDU DAN LUAS SALURAN BUANG TERHADAP PRESTASI TURBIN VORTEX
Authors: Sihombing Saudara V. , Syahril Gultom  , Terang UHSG  , Nasution Dian Morfi , Napitupulu Farel H.
Published: May 2024

Turbin vortex adalah turbin yang memanfaatkan pusaran air sebagai penggerak sudu turbin dengan head yang rendah dan bisa digunakan pada aliran sungai.Pada penelitian ini digunakan 3 dimensi sudu yang berbeda dengan bentuk casing lingkaran dan memiliki 3 variasi saluran buang dan ketinggian poros dari dasar casing.Penelitian ini dilakukan dengan memanfaatkan pompa sebagai sirkulator air dan menggunakan talang sebagai saluran masuk rumah turbin.Langkah-langkah yang dilakukan dalam penelitian ini meliputi perancangan, pembuatan turbin vortex, dan pengujian torsi turbin.Hasil penelitian menunjukkan bahwa sudu 3,yaitu dengan dimensi tinggi 78,3 cm dan lebar 13,5 cm memiliki efisiensi lebih tinggi dibandingkan dengan sudu yang lainnya dengan menggunakan diameter saluran buang 7cm.
PERANCANGAN INSULATION MATERIAL MESIN MIXER KAPASITAS 6,9 LITER DAN PUTARAN 280 RPM
Authors: Siregar Andri P. , Alfian Hamsi  , M. Sabri  , Indra  , Ikhwansyah Isranuri  , Bustami Syam
Published: May 2024

Proses pencampuran dimaksudkan untuk membuat suatu bentuk uniform dari beberapa konstituan bahan cair, pasta, dan padat. Dalam kehidupan nyata alat pencampur (mixer) dapat menghasilkan suatu produk dengan homogenitas yang lebih tinggi daripada pencampuran bahan yang dilakukan secara manual atau tanpa alat (dengan tangan saja). Dalam hal ini mesin mixer dengan menggunakan elemen pemanas merupakan penemuan terbaru yang belum ada dipasaran. Pada mesin ini variasi suhu dan putaran bisa diatur ketika proses pencampuran, dilengkapi dengan insulation material berbahan rockwool untuk menahan panas tidak keluar dari sistem. Panas yang terjadi pada rockwoll adalah 76,11ºC, panas yang terjadi pada pelat aluminium adalah 55,72 ºC dan effisiensi sistem bejana pemanas 51,55 %.
PENGARUH KOMPOSISI BLOWING AGENT PADA MATERIAL BETON RINGAN (CONCRETE FOAM) YANG DIPERKUAT SERAT TANDAN KOSONG KELAPA SAWIT
Authors: Sembiring Sony A. , Syam Bustami , Abda Syahrul , Sabri M. , Indra  , Mahadi
Published: May 2024

Indonesia merupakan salah satu produsen kelapa sawit terbesar di dunia. Selama ini tandan kosong kelapa sawit (TKKS) yang merupakan hasil dari pengolahan kelapa sawit hanya digunakan sebagai pupuk. Pada penelitian ini dilakukan riset yang akan menambah nilai ekonomis dari tandan kosong kelapa sawit. Tujuan dari penelitian ini adalah untuk mendapatkan proses pembuatan yang sesuai dengan kemampuan beton, mendapatkan komposisi material yang sesuai dengan kemampuan beton, serta mendapatkan tegangan dan regangan struktur beton ringan yang diperkuat serat TKKS akibat bebat statik. Pengujian yang dilakukan terhadap benda uji yang telah dihasilkan adalah pengujian tarik belah. Dari hasil penelitian ini didapat kesimpulan bahwa perbandingan antara tinggi cetakan dengan volume bahan campuran material beton ringan (Concrete foam) adalah 1:0,75. Komposisi material dari beton ringan (Concrete foam) yang terbaik adalah komposisi K3: semen 23,7%; pasir 47,4%; air 14,7%; blowing agent 12,9%; serat TKKS 1,3%. Hasil dari pengujian tarik belah diperoleh nilai tegangan adalah 275.324,9 Pa, regangannya adalah 0,11 dan modulus elastisitasnya adalah 2,4 MPa.
PENGARUH STRUKTUR MIKRO TERHADAP SIFAT MEKANIS BAJA STAINLESS STEEL M303 EXTRA UNTUK BAHAN MATA PISAU PEMANEN SAWIT
Authors: Rukmana Indra , Indra  , Ariani Farida , Sabri M. , Isranuri Ikhwansyah , Mahadi
Published: May 2024

Perlakuan panas (heat treatment) didefenisikan sebagai kombinasi operasi pemanasan dan pendinginan yang terkontrol dalam keadaan padat untuk mendapatkan sifat-sifat tertentu pada baja/logam atau paduan. Salah satu metode perlakuan panas tersebut dengan proses quenching dan tempering. Proses ini dilakukan pada temperatur austenite (10000C) selama 60 menit kemudian didinginkan dengan oli dan air es, kemudian di-temper pada temperature 3000C, 3500C, 4000C, 4500C, 5000C, 5500C dan 6000C dengan lama waktu penahanan 1 jam. Hasil pengujian memperlihatkan bahwa nilai kekerasan optimum adalah 506,6 BHN setelah quenching dengan oli pada suhu 10000C dan pada proses tempering rata – rata secara bertahap menurun dengan bertambahnya temperatur tempering. Sedangkan nilai kekerasan setelah quenching dengan air es pada suhu 10000C adalah 499,2 BHN dan pada proses tempering kekerasannya rata – rata secara bertahap menurun dengan bertambahnya temperatur tempering, namun pada temperatur tempering 4500C kekerasanya naik yang didapat 426,6 BHN. Hal ini disebabkan laju difusi lambat hanya sebagian kecil karbon yang dibebasakn, hasilnya sebagian struktur tetap keras tetapi mulai kerapuhannya. Hasil pengujian tarik memperlihatkan nilai yang optimum diperoleh tegangan luluh (yield strength) 1155,671 MPa dan tegangan batas (ultimate strength) 1335,313 MPa. Hasil pengujian fatique diperoleh kekuatan lelah 313833600 N selama 307680 detik dengan beban 7 Kg pada raw material. Menurunnya besar butir dari raw material 3,83l μm menjadi 2,86 μm setelah quenching dengan oli dan air es, dan setelah tempering rata – rata kenaikan besar butir secara bertahap meningkat dengan bertambahnya temperatur tempering. Dari penelitian dapat disimpulkan bahwa pada proses tempering dapat menurunkan nilai kekerasan dan kekuatan tarik. Sementara hasil mikro struktur memperlihatkan bahwa diameter butiran bahan menunjukkan menurunnya diameter butiran selama proses hardening dengan quenching oli. Dimana semakin kecil diameter butiran maka sifat mekanis bahan meningkat.
RANCANG BANGUN ALAT PENGUJI KAPASITAS ADSORPSI PADA MESIN PENDINGIN ADSORPSI DENGAN MENGGUNAKAN ADSORBEN KARBON AKTIF
Authors: Purba Oloan , Sitorus Tulus B. , Ambarita Himsar , Napitupulu Farel H. , Nasution Dian M.
Published: May 2024

Akhir-akhir ini mesin pendingin siklus adsorpsi semakin banyak diteliti oleh para ahli karena disamping ekonomis juga ramah lingkungan dan menggunakan energi terbarukan yaitu energi surya. Agar proses adsorpsi dan desorpsi mesin pendingin adsorpsi dapat berjalan dengan baik perlu diketahui jumlah perbandingan yang ideal antara adsorben dengan refrigeran yang digunakan. Data tersebut dapat dicari menggunakan alat penguji kapasitas adsorpsi. Alat penguji kapasitas adsorpsi yang digunakan dilengkapi dengan lampu halogen 1000 W sebagai sumber panas. Adsorber pada alat penguji ini terbuat dari bahan stainless steel yang bertujuan agar tahan terhadap korosi akibat dari variasi refrigeran yang digunakan. Karbon aktif yang digunakan sebagai adsorben yang terbuat dari bahan dasar batok kelapa sebanyak 1 kg. Sedangkan variasi refrigeran yang digunakan ada 4 yaitu metanol, etanol, amonia dan musicool. Diperoleh refrigeran yang paling optimal pada proses adsorpsi-desorpsi adalah metanol. Kapasitas metanol yang dapat diadsorpsi dan didesorpsi oleh adsorben karbon aktif adalah sebanyak 275 mL.
STRATEGI BERSAING OPTIMALISASI POTENSI BISNIS PORANG
Authors: Budiman Arief
Published: May 2024

The porang plant (Amorphophallus oncophyllus) is a member of the Araceae family which is generally known as the corpse flower because of its unpleasant flower odor. Porang is a new commodity that can provide added value for both farmers and companies that manage porang. Based on data obtained and reported from Kominfo, it is known that one hectare of porang land can produce 15-20 tons. Porang had been predicted as a leading export commodity, but when the government determined it as a leading commodity, the price of porang actually dropped even more. Many Porang farmers have complained about falling selling prices. Therefore, the main objective of this research is to see how to optimize Porang as a promising business opportunity, making a superior commodity that is feasible to be developed. This study uses a descriptive qualitative analysis tool, with a case study in the Ngrayun Ponorogo area, East Java. The conclusion of this study is that in fact there are several challenges that need to be considered by the government, including (i) increasing production, especially related to the productivity level of porang; (ii) marketing and (iii) Porang's business market structure which tends to be oligopsonic.
Quadratic Programming Approach in the Non-Negatif Matrix Factorization
Authors: Simbolon Heri Yusus , Sawaluddin  , Ramli Marwan
Published: May 2024

Non-negative Matrix Factorization is an iteration optimization algorithm. ie to decipher one matrix into several non-negative component matrices. Non-negative Matrix Factorization (FMN) serves to obtain a picture of non-negative data. There is a problem in the Non-negative Matrix Factorization that is optimization at the constraint boundary, where in the optimization solution on the constraint boundary it is necessary to do long iteration and of course very difficult and conquers a long time. Quadratic Programing is an approach to solving linear optimization problems where the constraint is linear function and its purpose function is the square of the decision variable or multiplication of the two decision variables. This method is considered to be an effective method to overcome the optimization in the Non-negative Matrix Factorization.
PENGARUH KONFLIK, TEKANAN PEKERJAAN DAN STRES KERJA TERHADAP PRODUKTIVITAS KERJA PEGAWAI DI KANTOR BKPSDM (BADAN KEPEGAWAIAN & PENGEMBANGAN SUMBER DAYA MANUSIA) KOTA LUBUKLINGGAU
Authors: Dora Maresta , Wahyuni Wahyuni , Anjelina Mutiara
Published: May 2024

Penelitian ini bertujuan untuk meneliti pengaruh konflik, tekanan pekerjaan dan stres kerja, terhadap produktivitas kerja pegawai di kantor BKPSDM Kota Lubuklinggau. Penelitian ini menggunakan jenis data sekunder bersifat kualitif. Populasi dalam penelitian ini adalah 50 orang. Analisis dalam penelitian ini menggunakan analisis Regresi Linier dengan menggunakan SPSS VERSI 20. Berdasarkan hasil uji menunjukkan bahwa hasil koefisien determinasi (R2) dari 3 variabel ke Y diperoleh 0,915 atau 91,5%.  Uji F diperoleh F hitung sebesar 165.482 dengan nilai signifikansi 0,000 < 0,05 maka H0 ditolak. Ini berarti variabel Pengaruh knflik kerja, tekanan pekerjaan dan stres kerja berpengaruh secara simultan terhadap variabel produktivitas kerja pegawai di kantor BKPSDM Kota Lubuklinggau. Sedangkan untuk uji t konflik kerja memiliki pengaruh positif dan signifikan terhadap produktivitas kerja terlihat dari hasil uji t diperoleh nilai t hitung 6,108 dengan nilai sig  0,000 < 0,05 maka H0 ditolak. Sedangkan nilai t hitung tekanan pekerjaan sebesar 2,341 dengan nilai sig 0,024< 0,05 terhadap produktivitas kerja. Sedangkan nilai t hitung stres kerja sebesar 4.590 dengan nilai sig 0,000 < 0,05 artinya memiliki pengaruh positif terhadap produktivitas kerja
PENGARUH LINGKUNGAN KERJA DAN DISIPLIN KERJA TERHADAP KINERJA PEGAWAI DINAS BADAN PENELITIAN DAN PENGEMBANGAN KABUPATEN MUSI RAWAS
Authors: Azhar Rudi , Susilawati Susilawati
Published: May 2024

Penelitian ini bertujuan untuk menguji secara empiris pengaruh lingkungan kerja dan disiplin kerja terhadap kinerja pegawai pada Dinas Badan Penelitian Dan Pengembangan Kabupaten Musi Rawas. Populasi dalam penelitian ini adalah pegawai Dinas Badan Penelitian Dan Pengembangan Kabupaten Musi Rawas. Sampel dalam penelitian ini adalah seluruh pegawai Dinas Badan Penelitian Dan Pengembangan Kabupaten Musi Rawas yaitu sebanyak 35 responden. Data yang digunakan adalah data primer yang diperoleh dari hasil penyebaran kuesioner kepada pegawai Dinas Badan Penelitian Dan Pengembangan Kabupaten Musi Rawas. Metode yang digunakan adalah analisis regresi linier sederhana dan berganda. Dari pengujian menunjukkan bahwa hipotesis pertama yaitu lingkungan kerja berpengaruh terhadap kinerja pegawai, hal ini dibuktikan dengan hasil analisis uji t yang menunjukan nilai t hitung = 9,711 lebih besar dari nilai ttabel (35-1=34) = 2,032 dengan nilai signifikan 0,000 < 0,05. Hipotesis kedua yaitu disiplin kerja berpengaruh terhadap kinerja pegawai, hal ini dibuktikan dengan hasil analisis uji t yang  menunjukkan nilai t hitung = 10,793 lebih besar dari nilai ttabel (35-1=34) = 2,032 dengan nilai signifikan 0,000 < 0,05.. Dan hipotesis ketiga yaitu lingkungan kerja (X1) dan disiplin kerja (X2) secara simultan berpengaruh terhadap kinerja pegawai (Y), hal ini dibuktikan dari hasil analisis uji F menunjukkan nilai F hitung= 110,436 lebih besar dari nilai  F tabel  3,295 dengan tingkat signifikan = 0,000 < 0,05.
ANALISIS KUALITAS LAYANAN PELANGGAN CAFE LAUNDRY MEDAN
Authors: Meisanni Meisanni , Nugroho Ngajudin
Published: May 2024

Perkembangan dan permintaan dibidang usaha jasa menjadikan layanan sebagai suatu tolak ukur dalam mempertahankan konsumen  dan sebagai pembeda dari layanan jasa pesaing. Kualitas layanan menentukan seberapa jauh perbedaan antara harapan dan kenyataan yang dirasakan dari pelayanan yang diterima baik sebagian maupun keseluruhan.Tujuan dalam penelitian ini adalah untuk mengetahui dan memahami kualitas layanan yang diharapkan oleh pelanggan Cafe Laundry sehingga dapat meningkatkan Kembali jumlah pelanggan. Metode penelitian yang dipakai adalah metode kualitatif dengan pengumpulan data melalui wawancara semiterstruktur. Sampel dalam penelitian ini adalah 8 orang pelanggan dari Cafe Laundry yang dipilih dengan kategori 4 orang pelanggan tetap yang sudah lebih dari 5 kali menggunakan jasa Cafe Laundry serta 4 orang pelanggan baru dengan minimal penggunaan jasa 1 kali. Pengambilan sampel menggunakan teknik purposive sampling. Hasil penelitian menunjukkan kualitas layanan Cafe Laundry cukup baik mulai dari fasilitas fisik yang disediakan, kemudahan transaksi pembayaran, karyawan yang cepat tanggap serta tersedianya layanan antar – jemput pakaian. Adapun yang perlu ditingkatan Cafe Laundry untuk menghasilkan layanan optimal dan mengatasi menurunnya jumlah pelanggan yaitu ketepatan waktu dalam antar-jemput pakaian, kebersihan area laundri, respons yang cepat dalam komunikasi online, memperbaiki respon karyawan yang kurang sopan dan ramah serta meningkatkan hasil cucian yang kurang maksimal.
MEMBUKA PINTU DUNIA: EKSPLORASI TREN BISNIS PARIWISATA DI KABUPATEN LAMPUNG SELATAN DALAM PERSPEKTIF GLOBAL
Authors: Herinanto Dwi , Gumanti Miswan
Published: May 2024

The background to the study of global trends related to tourism and creative business in Lampung Province, Indonesia, emerges from the importance of understanding the global dynamics that affect the development of these sectors at the local level. The phenomenon of globalization has changed the landscape of the tourism industry and creative business significantly. By understanding global trends related to tourism and creative, the Province of Lampung can identify opportunities, overcome challenges, and develop appropriate strategies to increase competitiveness and strengthen the contribution of tourism sector and creative enterprises to economic growth and sustainable development. The city of Lampung Selatan offers a wide range of tourist products, ranging from natural beauty, such as beaches, mountains, and waterfalls, to cultural heritage, like temples and museums. This diversification allows tourists to enjoy a variety of experiences during tourist visits. Exploring tourism business trends in Lampung City in a global perspective requires a holistic and planned approach for local governments among them: analysis of global trends, strengthening tourism infrastructure, digital promotion, development of tourist packages, international partnerships, environmental and cultural preservation, investing in SDM training, as well as environment and cultural conservation.
PENGARUH PENGEMBANGAN KARIR DAN SELF-EFFICACY TERHADAP KINERJA KARYAWAN DI PT. LAUTAN BERLIAN UTAMA MOTOR LUBUKLINGGAU
Authors: Surajiyo Surajiyo , Rahman Elzanti , Aprianto Ronal , Suyadi Suyadi
Published: May 2024

Kinerja menjadi landasan yang sesungguhnya bagi organisasi karena tanpa adanya kinerja maka tujuan yang dimiliki oleh organisasi tidak dapat dicapai. Tujuan dari penelitian ini adalah untuk mengetahui dan menganalisis pengaruh Pengembangan Karir dan Self-Efficacy terhadap kinerja karyawan Di PT. Lautan Berlian Utama Motor Lubuklinggau. Penelitian ini merupakan penelitian dengan metode kuantitatif dengan pendekatan asosiatif. Populasi dalam penelitian ini yaitu seluruh karyawan Di PT. Lautan Berlian Utama Motor Lubuklinggau. Penelitian ini menggunakan sampel jenuh, dimana semua populasi dijadikan sebagai responden yang berjumlah 32 orang karyawan . Teknik pengumpulan data dalam penelitian ini adalah observasi, wawancara dan penyebaran kuesioner . Teknik analisis data dalam penelitian ini menggunakan Analisis Outer Model, Reliabilty, Analisis Inner Model, dan Uji Hipotesis. Penelitian ini menggunakan software SmartPLS 3.0 untuk melakukan pengolahan data. Hasil penelitian ini menunjukkan bahwa : 1) Terdapat pengaruh Pengembangan Karir terhadap kinerja karyawan Di PT. Lautan Berlian Utama Motor Lubuklinggau, 2) Terdapat pengaruh Self-Efficacy terhadap Kinerja Karyawan Di PT. Lautan Berlian Utama Motor Lubuklinggau, 3) Terdapat pengaruh Pengembangan Karir dan Self-Efficacy Terhadap Kinerja Karyawan Di PT. Lautan Berlian Utama Motor Lubuklinggau.
Spectrophotometric Determination of Ranitidine-HCl in Pure Form and Pharmaceutical Formulations with Metol and potassium hexacyanoferrate (ΙΙΙ)
Authors: Abdulwahab Abeer Qays
Published: May 2024

A simple, sensitive and accurate spectrophotometric method of determination of Ranitidine-HCl (RNH) in pureform and its pharmaceutical formulation. Was used in this studyThe method is based on the formation of (RNH)complex. The reaction between the Ranitidine-HCl with the mixture of metol and potassium hexacyanoferrate (ΙΙΙ) was evaluate metol ( Nmethyl – p - aminophenosulphate ) for the spectrophotometric determination of the Ranitidine - HCl . The maximum absorbance of the colored complex occurred at λ = 540nm. Reaction conditions have been optimized to obtain (RNH) complex of high sensitivity and longer stability. Under optimum conditions the absorbance of the (RNH) complex where found to increase linearly with the increase in concentration of the Ranitidine-HCl which corroborated with correlation coefficient value. Of 0.09995with concetration ranges of(2-90) μg /ml relative standard deviation and relative error of prediction for drug were lower . The proposed method was successfully applied to determine of the selected Ranitidine-HCl in pure form and pharmaceutical formulations with good precision and accuracy compared to standard method as revealed by t- and F- values , the results obtained agree well with the labeled contents.
Synthesis and Theoretical Study of new Schiff base derivatives
Authors: AL-Rubaie Leaqaa A.
Published: May 2024

The study include preparation two Schiff base compounds , 4-acetoamidobenzylidine-glycine SB-A and 4-acetoamidobenzylidine –nitrourea SB-B . Schiff bases were prepared by condensation of 4-acetanilbenzaldehyde with nitrourea and other with glycin. The products were characterized by both FT- IR and UV-Vis. Spectroscopyphotometry. The biological activities against selected types of bacteria which included gram positive bacteria (staphylococcus aureus), and gram negative bacteria (Escherichia coli, proteus sp., pseudomonas aeruginosa) was studied. Later, theoretical studies by using the optimized geometry molecular structures of both compounds, indicates SB-B is more stable than SB-A.
Valoración del patrimonio cultural y natural de un territorio. El caso del valle de Ameca, Jalisco
Authors:   Universidad de Guadalajara, Guerrero Muñoz José Francisco
Published: May 2024

En la actualidad, la ciencia y la tecnología provocan impactos positivos y negativos en las comunidades y en el ambiente, además constituyen los principales medios para la solución de problemas que atañen a la sociedad contemporánea. Este nuevo panorama se presenta de manera compleja y obliga a una reflexión más profunda acerca de la identificación y valoración del patrimonio cultural y natural por la gran cantidad de aspectos que lo determinan, esto significa que es preciso abordar dicha problemática con un enfoque sistémico que permita efectuar el ejercicio que aquí se propone de manera integral, sin aislarlo de la influencia de los aspectos científicos y tecnológicos presentes en todo territorio.
Calidad educativa. Concepto, contexto y percepción del profesorado
Authors:   Universidad de Guadalajara, Marúm Espinosa Elia , Rosario Muñoz Víctor Manuel , Mustre León José , Nieto Caraveo Luz María , Kent Serna Rollin , Valle Gómez-Tagle Rosa María , Barrenetxea Ayesta Miren , Cardona Rodríguez Antonio , Mijangos del Campo Juan José , Olaskoaga Larrauri Jon , Curiel Gutiérrez Federico , Padilla Muñoz Ruth , Robles Ramos María Lucila
Published: May 2024

La educación, sin duda, impacta en la transformación de las sociedades, pero a su vez su capacidad de cambio está condicionada por la relevancia que la misma sociedad le concede. En este círculo virtuoso que se puede establecer entre educación y transformación social es difícil identificar el verdadero valor agregado que aporta la educación si no se consideran de manera especial los contextos externos (mediato e inmediato) e internos (entradas y procesos) en que trabajan las escuelas o el profesorado. Impacto y relevancia de la educación son dos caras de una misma moneda: la acción educativa.
Mediji i mentalno zdravlje
Authors: Đumić Tihana
Published: May 2024

Cilj istraživanja bio je pregledati novije znanstvene radove vezane uz utjecaj medija na mentalno zdravlje ljudi, pri čemu se očekuje značajno više negativnih posljedica korištenja medijskog prostora na mentalni status pojedinaca od onih pozitivnih. U tu svrhu korištena je deskriptivna metoda analize i sinteze prema PRISMA smjernicama radova iz pretraživača Web of Science u razdoblju od 2021. do 2023. godine. Pregled i analiza aktualnih radova podupiru ranija saznanja o većinom negativnom utjecaju medija na mentalno dobro stanje čovjeka, s time da se značajan naglasak stavlja i na pozitivne učinke medija na psihološku i mentalnu dobrobit, što ostavlja dovoljno prostora za osnaživanje protektivnih faktora u vrijeme neminovno digitalne ere čovječanstva.
Ex vivo quantification of lanthanum and gadolinium in post-mortem human tibiae with estimated barium and iodine concentrations using K X-ray fluorescence
Authors: Nguyen Joanna , Crawford Daniel , Howarth David , Sukhu Balram , Pejović-Milić Ana , Gräfe James L
Published: May 2024

Objectives: Lanthanum (La) and gadolinium (Gd) are known to deposit in bone of exposed populations, namely those who are orally administered lanthanum carbonate (LaC, La2(CO3)3) or are injected with Gd-based contrast agents, respectively. In this work, bone La and Gd concentrations from the environment and diet were measured using x-ray fluorescence in ten post-mortem human tibiae. As a secondary objective, bone barium (Ba) and iodine concentrations were estimated.

Approach: Two calibration lines were produced for La and Gd and the minimum detection limits (MDLs) of the system were determined using a 180° irradiation-detection geometry.

Main results: The MDLs of the system were 0.4 µg La g-1 bone mineral and 0.5 µg Gd g-1 bone mineral. The mean concentrations were -0.02 ± 0.1 µg La g-1 bone mineral and 0.1 ± 0.2 µg Gd g-1 bone mineral in tibiae. The average Ba and iodine concentrations estimated from the experimental La calibration line and Monte-Carlo derived sensitivity factors were determined to be 3.4 ± 0.8 µg Ba g-1 bone mineral and -0.5 ± 0.3 µg iodine g-1 bone mineral. Since it was discovered that four donors previously received an iodine-based contrast agent, the mean concentrations in these donors was 27.8 ± 28.4 µg iodine g-1 bone mineral.

Significance: The XRF system has determined baseline concentrations of these four heavy metals in trace quantities from natural exposure pathways (with the exception of iodine in four donors). This indicates that the system can measure low levels in ex vivo tibiae samples and can potentially be further developed for in vivo studies involving live subjects who are directly exposed to these metals.