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The 2006 Yogyakarta earthquake, with a magnitude of 6.3 Mw, caused severe structural damage and significant casualties, highlighting the high seismic vulnerability in the Special Region of Yogyakarta (DIY). Tectonic activity in this region is strongly influenced by the subduction of the Indo-Australian Plate beneath the Eurasian Plate and the presence of active faults, particularly the Opak Fault. Local geological conditions dominated by young volcanic deposits and unconsolidated alluvial sediments further enhance seismic wave amplification. This study aims to estimate the Peak Ground Acceleration (PGA) in Prambanan District using the empirical McGuire (1977) attenuation relationship based on parameters from the 2006 earthquake. Analysis was conducted on 113 observation points to map the spatial distribution of ground acceleration. The results indicate that PGA values range from 29.2 to 35.6 gal, with the highest values concentrated in the southern and southeastern parts of Prambanan, characterized by alluvial deposits of the Opak River. In contrast, lower PGA values occur in the northern area underlain by more consolidated young volcanic materials. These findings emphasize the significant influence of lithology and geomorphology on local site response to seismic shaking. The results provide an important basis for seismic hazard assessment and mitigation planning in Prambanan and surrounding areas.

The Taman Candi is included in the category of active green open space (GOS). Based on this, it is necessary to carry out good maintenance aimed at maintaining the quality of facilities, both softscape and hardscape in the park. Maintenance in Taman Candi Ngawi Regency refers to the park maintenance standards by Arifin and Arifin (2005). Data processing was carried out using a quantitative method, namely using a work capacity calculation formula, aimed at measuring the suitability of work and worker effectiveness from the maintenance of the Taman Candi Ngawi Regency. The management of the Taman Candi in Ngawi Regency does not have a written maintenance schedule, so maintenance activities are carried out flexibly or according to the conditions in the field, and there are several activities that have not been carried out, the results show that there is still work that is not ideal from the work capacity and exceeds the ideal value in accordance with the standard of maintenance work capacity of Arifin and Arifin (2005). This is due to the lack of knowledge of workers about good and correct maintenance activities, the absence of a written schedule from the manager, and the lack of availability of tools.

This study analyzes customer attrition in barbershops through the application of the 4P marketing mix, which includes Product, Price, Place, and Promotion. The research was conducted using a questionnaire distributed to 30 barbershop customers, which aimed to assess their level of satisfaction regarding each element of the marketing mix. The findings revealed that while customers were generally satisfied with the quality of the haircuts and the cleanliness of the tools, there was an important demand for improvement in the quality and variety of additional products offered. The pricing strategy was considered affordable by most customers; however, some expressed dissatisfaction, indicating the need for better communication regarding the value of the services provided. Demographic analysis showed that the majority of respondents were young adults aged 18-25, highlighting a specific target market for barbershops. Overall, this study emphasizes the importance of effectively implementing the marketing mix to improve customer retention and satisfaction in the barbershop industry.

The Special Region of Yogyakarta (DIY) is characterized by high seismic activity due to its proximity to the subduction zone and the presence of active fault systems, particularly the Opak Fault. The 2006 Yogyakarta earthquake revealed significant vulnerability in local building structures and highlighted the complex geological conditions governing seismic wave propagation. This study aims to calculate and map the Peak Ground Acceleration (PGA) distribution in Prambanan District, Klaten Regency—one of the areas closest to the 2006 earthquake source. PGA values were estimated using the McGuire attenuation relationship, based on a moment magnitude of Mw 6.3 and the hypocentral distance to 88 observation points distributed at approximately 900-meter intervals. The resulting PGA map indicates values ranging from 26.7 to 31.7 gal, with a clear spatial trend showing increasing intensity from the northern to the southern parts of the study area. Higher PGA values occur in regions near the Opak Fault and in areas dominated by unconsolidated volcanic deposits of the young Merapi formation. These loose sediments amplify seismic waves, resulting in stronger ground motion compared to areas composed of more compact sedimentary rocks. The spatial pattern of PGA corresponds well with the distribution of structural damage recorded during the 2006 earthquake. The findings emphasize the significant role of local geology and fault proximity in shaping seismic hazard levels. Consequently, this study provides essential insights for disaster mitigation strategies, land-use planning, and structural vulnerability assessment within the Prambanan area.

Coal quality must be controlled from the pit area to the ROM stockpile to ensure compliance with market specifications. However, hauling and stockpiling processes often lead to changes in coal characteristics. This study aims to analyze variations in proximate parameters between coal from Pit B1 and ROM Stockpile Km4 at PT Trisensa Mineral Utama and to identify factors contributing to these changes. The methodology includes field sampling at both locations, sample preparation based on ASTM standards, and laboratory testing of inherent moisture, residual moisture, ash content, volatile matter, and fixed carbon. The results indicate that coal undergoes quality changes after being stored in the stockpile, marked by a decrease in inherent moisture of 2.54% (from 17.64% to 15.10%), a decrease in residual moisture of 1.42% (from 17.17% to 15.75%), a slight reduction in ash content of 0.16%, a decline in volatile matter of 0.28%, and a reduction in fixed carbon of 0.18%. These changes are influenced by field conditions, material contamination during mining, rainfall, coal porosity, and handling activities at the stockpile. The findings highlight the need for improved sampling management, better surface water control, and stricter material handling procedures to minimize coal quality degradation.

This study examines human facial proportions through an anthropometric approach based on the Phi value of the Golden Ratio (φ = 1.618) to understand the relationship between mathematical proportionality and visual aesthetics. The analysis focuses on two public figures, Jin and V of BTS, who are widely recognized as visual representatives within contemporary popular culture. Using two-dimensional anthropometric measurements, four primary facial aspects were evaluated: the facial length-to-width ratio, the proportional relationship between the forehead, nose, and chin, the eye–mouth–chin vertical proportion, and the alignment of eye width with interocular distance. Each measurement was compared to the Phi value to assess its degree of proportional conformity. The findings indicate that most facial ratios observed in both Jin and V closely approximate or match the Golden Ratio, with V exhibiting the highest precision in vertical proportional measurements, while Jin demonstrates more consistent overall proportional stability across multiple facial components. These results support the use of the Phi Golden Ratio as a mathematical indicator in assessing facial proportion and aesthetic harmony. Nevertheless, the study acknowledges that visual aesthetics remain inherently subjective and are influenced by cultural context and individual perception. Thus, anthropometric analysis based on the Golden Ratio can serve as a complementary tool in understanding human facial aesthetics.  

Mine disposal materials such as tailings, overburden, and waste rocks are critical components in mining operations that require comprehensive understanding of their geotechnical properties to ensure stability and safety of storage facilities. This literature review aims to analyze the role of particle gradation and mineralogical composition in determining shear strength and compressibility of mine disposal materials, with particular focus on nickel mining. A sistematic literature review method was employed by analyzing 30 scientific publications from 2019-2025 obtained from various academic databases. The review findings indicate that particle size distribution (gradation) has significant influence on shear strength and compressibility, where materials with coarser gradation and higher coefficient of uniformity (Cu) exhibit greater shear strength and lower compressibility. Mineralogy, particularly clay mineral content, increases cohesion and microporosity but also increases compressibility under loose conditions. Studies on nickel mine waste demonstrate that ferronickel slag possesses favorable drainage characteristics suitable for rockfill material, while tailings require strict gradation control. In conclusion, comprehensive characterization integrating gradation parameters (Cu, Cc, D50) with mineralogical analysis (XRD, XRF) is essential for predicting mechanical behavior of mine disposal materials and designing safe storage facilities.

The development of smart cities has become a strategic priority for local governments seeking to enhance citizens’ quality of life, strengthen sustainable development, and improve public space management. Kambang Iwak Park in Palembang represents one of the city’s major urban green spaces that has undergone significant revitalization and serves as a case study for smart city implementation in public areas. This study analyzes the application of Cohen’s six smart city dimensions—Smart People, Smart Living, Smart Government, Smart Economy, Smart Mobility, and Smart Environment—and their relationship with Carmona’s six urban design dimensions. This qualitative–descriptive research utilizes visual observations, historical data, and facility documentation extracted from the provided presentation. The findings indicate that Kambang Iwak Park effectively integrates several smart city dimensions, particularly Smart Living, Smart Environment, and Smart Mobility. Nonetheless, issues such as irregular parking, insufficient smart services, and poorly organized street vendors remain challenges. The study concludes that integrating smart city principles with urban design concepts enhances public space quality and supports sustainable urban development in Palembang.

The oil and gas industry plays a crucial role in meeting global energy needs, with crude oil from production wells being the primary product of upstream operations. Prior to further processing, crude oil requires pretreatment at the production site, one of the key stages being phase separation using a flash separator. This study examines the effect of variations in cooling temperature on the performance of liquid phase separation and energy requirements in the flash separation process of light hydrocarbons. The analysis was conducted through process simulation using Aspen HYSYS version 14.2 with the Peng Robinson property package. The feed stream had a mass rate of 10,000 kg per hour, a temperature of 50°F, and atmospheric pressure, with compositions of ethane, propane, isobutane, and normal butane. The process configuration included compression, cooling, and phase separation in a flash separator at a constant pressure of 50 psia. Variations in cooling temperature were applied at 20, 10, and 0°C. The simulation results indicated a thermodynamic critical point at 10°C. At 20°C, no liquid phase was formed, while at 10°C, significant liquid yield was obtained with moderate energy consumption. Lowering the temperature to 0°C dramatically increases liquid recovery, but the cooling energy requirement also increases sharply. Sensitivity analysis confirms a strong inverse relationship between temperature and condensation yield, as well as a surge in energy consumption at low temperatures. The optimal operating condition is set at 10°C, providing a balance between separation efficiency and energy efficiency in accordance with sustainable manufacturing principles.

This research investigates the Peak Particle Velocity (PPV) resulting from blasting operations at Pit Pinang, PT Bukit Baiduri Energi, employing two prediction approaches: Non-Linear Geometric Regression and the USBM Oriard’s Formula. Ground vibration measurements were recorded over a one-month period, from October 9 to November 8, 2025. The findings indicate that the non-linear regression model achieves a higher predictive accuracy of 78.62%, outperforming the USBM Oriard’s Formula, which reaches 68.2%. Variations between the observed and estimated PPV values were affected by factors such as the location of geophones, differences in explosive charges, and alterations in borehole depths. In addition, the study evaluates optimal explosive charge recommendations in accordance with SNI 7571:2010 standards to mitigate potential structural damage in surrounding areas. By highlighting these predictive discrepancies and providing practical guidance on charge management, the research offers valuable insights for improving blasting safety and minimizing vibration impacts on nearby infrastructure. The comparison of methods emphasizes the importance of selecting appropriate prediction models to ensure both operational efficiency and environmental safety.

Aktivitas ekonomi mempunyai hubungan yang erat dengan transaksi antara entitas ekonomi, yang terkadang menyebabkan sengketa. Dalam konteks ekonomi syariah, sengketa muncul karena perselisihan antara pelaku ekonomi yang berbisnis berdasarkan hukum ekonomi syariah terkait hak atau kepentingan. Sengketa ini bisa diputus dengan instrumen hukum yang berbagai, baik litigasi di pengadilan agama maupun metode non-litigasi seperti negosiasi, mediasi, dan konsiliasi. Penyelesaian sengketa di pengadilan agama bertujuan agar terjaminlah keadilan dan keteguhan hukum sesuai prinsip syariah. Namun, dengan semakin meningkatnya tuntutan keadilan, penyelesaian sengketa melalui pengadilan relatif lama dan kurang efektif, maka alternatif penyelesaian di luar pengadilan semakin relevan. Negosiasi sebagai salah satu proses tawar-menawar dalam sengketa ekonomi syariah sangat memfokuskan pada persiapan dan komunikasi efektif kedua belah pihak. Salah satu penyebab sengketa ekonomi pada ekonomi syariah adalah wanprestasi dalam transaksi jual beli, terutama transaksi tanah. Oleh karena itu, regulasi ekonomi syariah yang mengatur prinsip keadilan dan keseimbangan hak dan kewajiban sangatlah perlu untuk menyelesaikan sengketa tersebut secara adil dan damai. Penelitian ini bertujuan untuk menggali penerapan regulasi ekonomi syariah dalam penyelesaian sengketa wanprestasi, khususnya yang berhubungan dengan sengketa tanah, dengan mengidentifikasi metode penyelesaian sengketa yang sesuai dalam hukum Islam dan hukum positif Indonesia. Penelitian ini diharapkan memberikan wawasan mengenai relevansi dan penerapan hukum Islam dalam menyelesaikan sengketa ekonomi syariah, serta menyoroti pentingnya penyelesaian sengketa melalui metode yang mengedepankan keadilan dan perdamaian.

Penelitian ini membahas peran dan tanggung jawab Pejabat Pembuat Akta Tanah (PPAT) dalam pembuatan akta hibah, dengan fokus pada implikasi sengketa hukum yang terlihat pada Putusan Nomor 1316/Pdt.G/2023/PA.Jepr. Permasalahan dalam penelitian ini adalah tingginya jumlah sengketa terkait akta hibah di Indonesia yang menunjukkan belum optimalnya peran Pejabat Pembuat Akta Tanah (PPAT) dalam menjamin keabsahan dan legalitas dokumen. Kondisi ini menimbulkan pertanyaan mengenai bagaimana regulasi mengatur peran dan tanggung jawab PPAT dalam pembuatan akta hibah, serta bagaimana permasalahan hukum yang muncul dipertimbangkan oleh hakim dalam memutus perkara sengketa akta hibah tersebut. Metode penelitian yang digunakan adalah pendekatan kualitatif deskriptif, dengan pengumpulan data melalui studi dokumen, wawancara, dan literatur hukum. Penelitian ini menunjukkan bahwa tanggung jawab utama PPAT dalam pembuatan akta hibah mencakup syarat formil dan materiil sesuai PP No. 37/1998, KUH Perdata, dan KHI, termasuk verifikasi dokumen, identitas, status tanah, serta persetujuan ahli waris. Sengketa  dalam Putusan No. 1316/Pdt.G/2023/PA.Jepr, timbul akibat dugaan hibah fiktif dan kurangnya kehati-hatian PPAT, namun penggugat PPAT tidak dapat dibuktikan dan akta hibah secara administratif telah memenui syarat.Hakim menyatakan gugatan tidak diterima karena cacat formil Penelitian ini menyarankan agar PPAT lebih berhati-hati dalam menjalankan tugasnya dan lebih proaktif dalam mencegah potensi sengketa hukum terkait hibah tanah.

Perjanjian kredit antara lembaga perbankan dan pelaku usaha mikro, kecil, dan menengah (UMKM) merupakan instrumen penting dalam mendukung pertumbuhan ekonomi. Namun, dalam praktiknya, tidak jarang terjadi wanprestasi dari pihak debitur  yang  berdampak  pada  hubungan  hukum  dan keberlangsungan  usaha.  Penelitian  ini  bertujuan  untuk mengkaji: 1) bagaimana proses pengajuan dan pelaksanaan perjanjian kredit antara Bank BRI dan UMKM Konveksi Parasit di Daerah Istimewa Yogyakarta; 2) apa saja faktor yang menyebabkan terjadinya wanprestasi oleh debitur; dan 3) bagaimana mekanisme penyelesaian wanprestasi yang dilakukan oleh pihak bank. Metode penelitian yang digunakan adalah pendekatan yuridis normatif yang didukung oleh data primer. Spesifikasi penelitian bersifat deskriptif analitis dengan jenis dan sumber data berupa data sekunder yang diperoleh melalui studi pustaka, serta data primer yang diperoleh melalui wawancara dengan pihak terkait. Teknik analisis data dilakukan secara kualitatif untuk menginterpretasikan norma hukum dan fakta empiris secara sistematis. Hasil penelitian menunjukkan bahwa: 1) proses pengajuan kredit dilakukan melalui prosedur formal dengan dokumen pendukung yang sah, dan dituangkan dalam Surat Pengakuan Hutang; 2) wanprestasi terjadi karena kombinasi faktor internal seperti pengelolaan usaha yang kurang optimal dan faktor eksternal seperti penurunan permintaan pasar; dan 3) penyelesaian wanprestasi dilakukan melalui eksekusi agunan, pelaporan ke otoritas keuangan, serta pendekatan persuasif seperti restrukturisasi kredit. Penelitian ini menegaskan pentingnya edukasi hukum bagi pelaku UMKM dan penerapan prinsip keadilan dalam penyelesaian sengketa kredit.

Tanah adalah objek vital yang bernilai tinggi sehingga transaksi jual beli tanah menuntut kepastian hukum agar tidak menciptakan sengketa. Namun, praktik membeli atau menjual tanah secara tunai tanpa melalui PPAT dan tanpa memiliki sertifikat kepemilikan masih banyak terjadi, sehingga menimbulkan berbagai masalah terkait keabsahan dokumen, perlindungan hukum, serta risiko terjadinya sengketa. Latar belakang inilah yang melandasi penelitian dengan judul Perlindungan Hukum bagi Pembeli atas Tanah dalam Perjanjian Jual Beli: Studi Putusan Nomor 1990/K/PDT/2025. Penelitian ini ditulis guna menganalisis kekuatan hukum perjanjian jual beli tanah di bawah tangan dan menilai pertimbangan hakim dalam memberikan perlindungan hukum kepada pembeli. Metode penelitian yakni yuridis normatif dengan pendekatan perundang-undangan. Hasilnya ditemukan dalam Putusan Nomor 1990/K/PDT/2025, perjanjian yang telah dibuat oleh para pihak terkait jual beli tanah adalah sah dan bersifat mengikat. Para Tergugat dinyatakan wanprestasi atas mengurus penerbitan sertifikat pengganti maupun proses peralihan hak atas tanah. Selain itu, Majelis Hakim memerintahkan agar sertifikat pengganti segera diterbitkan, dilakukan pemecahan bidang tanah, dan dilaksanakan proses balik nama. Untuk menjamin kepastian pelaksanaan putusan, hakim memberikan kewenangan kepada pembeli untuk mengurus sendiri seluruh proses tersebut apabila penjual tetap lalai. Pertimbangan hukum ini mencerminkan sikap hakim yang berorientasi pada perlindungan hak pembeli beritikad baik sekaligus sebagai upaya menegakkan prinsip kepastian hukum dan rasa keadilan.

Penelitian ini membahas secara mendalam mengenai perlindungan hukum bagi nasabah dalam sengketa gadai syariah, khususnya yang berkaitan dengan pengembalian barang jaminan setelah pelunasan utang. Perkembangan industri gadai syariah di Indonesia yang sangat pesat menunjukkan adanya peningkatan kepercayaan masyarakat terhadap lembaga keuangan berbasis syariah. Namun, di sisi lain, dinamika ini juga memunculkan tantangan baru dalam aspek perlindungan konsumen, terutama ketika terjadi wanprestasi, kesalahan administrasi, atau kelalaian lembaga gadai dalam menjaga serta mengembalikan barang jaminan milik nasabah. Melalui pendekatan yuridis normatif dan studi kasus terhadap Putusan Pengadilan Agama Banjarmasin Nomor 1112/Pdt.G/2021/PA.Bjm, penelitian ini berupaya menganalisis bentuk tanggung jawab hukum lembaga gadai serta perlindungan yang seharusnya diterima oleh nasabah sebagai pihak yang dirugikan. Hasil kajian menunjukkan bahwa dalam perspektif hukum syariah, barang gadai (marhun) memiliki kedudukan hukum sebagai amanah yang wajib dijaga dengan penuh tanggung jawab oleh pihak penerima gadai (murtahin). Apabila lembaga gadai lalai dalam menjaga atau gagal mengembalikan barang tersebut, maka tindakan tersebut dapat dikategorikan sebagai wanprestasi sekaligus pelanggaran terhadap prinsip keadilan dan hak-hak konsumen. Perlindungan hukum terhadap nasabah diatur dalam berbagai peraturan, antara lain Kitab Undang-Undang Hukum Perdata (KUHPerdata), Undang-Undang Nomor 8 Tahun 1999 tentang Perlindungan Konsumen, serta pengawasan yang dilakukan oleh Otoritas Jasa Keuangan (OJK) terhadap lembaga keuangan syariah. Namun demikian, efektivitas implementasi peraturan tersebut masih menghadapi berbagai kendala, seperti lemahnya pengawasan, kurangnya pemahaman masyarakat mengenai hak-haknya, serta minimnya mekanisme penyelesaian sengketa yang cepat dan transparan. Oleh karena itu, diperlukan penguatan sistem pengawasan serta edukasi hukum bagi masyarakat agar prinsip keadilan, kepastian hukum, dan kemaslahatan dalam transaksi gadai syariah dapat terwujud secara menyeluruh.

Dalam pelaksanaannya, jaminan fidusia bisa dieksekusi dengan menggunakan sertifikat jaminan yang memiliki kekuatan hukum setara dengan putusan pengadilan yang sudah bersifat tetap dan mengikat. Namun dalam penerapannya, hal ini menimbulkan polemik karena adanya ketimpangan hukum, hingga terbitlah Putusan MK Nomor 18/PUU-XVII/2019. Penulisan ini membahas mengenai pengaturan kekuatan eksekutorial Pasal 15 ayat (2) dan (3) UU Jaminan Fidusia, baik sebelum maupun sesudah terbitnya Putusan MK Nomor 18/PUU-XVII/2019, dan implikasinya dengan menggunakan metode hukum normatif yang berlandaskan studi kepustakaan dengan pendekatan perundang-undangan dan kasus. Hasil yang didapatkan adalah parate eksekusi yang dijalankan cenderung melanggar prinsip due process of law, sehingga terjadi pergeseran paradigma dari sistem eksekusi yang absolut menuju sistem eksekusi yang berkeadilan dan sejalan dengan prinsip negara hukum yang menjamin kepastian serta perlindungan hak konstitusional para pihak. Pergeseran tersebut menjadikan pembagian hak dan kewajiban antara debitur dan kreditur menjadi lebih adil, transparan, dan sesuai dengan prinsip keadilan substantif.

Penelitian ini menganalisis dasar hukum dan tanggung jawab notaris dalam tindak pidana pemalsuan akta otentik berdasarkan Kitab Undang-Undang Hukum Pidana (KUHP) dan Undang-Undang Jabatan Notaris (UUJN). Notaris memiliki kewenangan membuat akta otentik yang berkekuatan hukum sempurna, namun hal ini juga menciptakan celah bagi pemalsuan yang merugikan. Pemalsuan akta termasuk tindak pidana pemalsuan surat, menimbulkan kompleksitas dalam menentukan batas tanggung jawab notaris karena kewajiban verifikasi notaris yang terbatas dalam investigasi materiil, serta adanya perbedaan pendekatan antara KUHP dan UUJN. Penelitian ini menggunakan metode hukum normatif dengan pendekatan statute dan conceptual, mengkaji peraturan dan literatur hukum. Hasilnya menunjukkan bahwa notaris dapat dikenakan sanksi pidana jika terbukti sengaja terlibat dalam pemalsuan. Kesimpulannya, diperlukan harmonisasi antara KUHP dan UUJN untuk memastikan kepastian hukum bagi notaris dan masyarakat, dengan penekanan pada pembuktian unsur kesengajaan (dolus) notaris.

This papper reviews a range of studies that examine the influence of cultural and religious differences on the effectiveness of the counselor–client relationship. The main focus is on how cultural identity and religious beliefs shape the way individuals understand problems, interpret personal experiences, and respond to the counseling process. The literature shows that differences in values, communication styles, and spiritual orientations can affect the quality of the relationship, especially during the stages of building trust and setting counseling goals. At the same time, counselors who possess multicultural competence and sensitivity toward religious diversity are better able to adapt their approaches so clients feel respected and emotionally secure. This review also highlights the importance of counselor self-reflection to avoid personal bias in sessions, particularly when working with clients from backgrounds that differ greatly from their own. By examining various academic sources, this article argues that an effective counseling relationship depends not only on technique but also on the counselor’s ability to understand the client’s life context. The findings of this literature review contribute to the development of more inclusive and culturally responsive counseling practices.

Nicotine is the main chemical substance found in cigarettes and has toxic and addictive properties. Exposure to nicotine in active smokers can cause various health problems, including respiratory and cardiovascular disorders and dependence. The prevalence of active smokers in RT 08 RW 05, Duren Jaya Village, East Bekasi Subdistrict is quite high. However, data on nicotine levels in the bodies of active smokers remain very limited. This study aims to determine the nicotine levels in active smokers in Duren Jaya Village, RT 08 RW 05, Bekasi Timur District, using urine samples. The research method employs a descriptive design with a cross-sectional approach. Urine samples were collected from 30 male active smokers aged over 35 years who had smoked for at least 15 years. Nicotine levels were measured at the Jakarta Regional Health Laboratory using Gas Chromatography-Mass Spectrometry (GC-MS). Data were analyzed descriptively using SPSS version 22. The study included 30 male respondents (100%) with an average age of 41 years. The analysis results showed nicotine levels ranging from 59.908 ng/mLto 459.941 ng/mL, with the majority of respondents falling into the category of active smokers based on the biological threshold for nicotine levels. It can be concluded that the results obtained indicate that these levels correspond to active smokers using light tobacco.

Multiple diastema is a space or gap between two or more adjacent teeth. Diastema management can be corrected using removable orthodontic treatment and eliminating etiological factors. Treatment in this case shows the progress of successful treatment of multiple diastema in Soelastri General Hospital using removable orthodontic appliances based on the indications and needs of patient care. Case management: A 24-year-old woman came to Soelastri General Hospital Surakarta with complaints of gaps in the teeth between the 4 lower front incisors. The patient's bad habit history is known to be tongue thrusting. Intraoral examination found interdental gaps in the 4 lower incisors measuring 33.32 (1.6mm), 32.31 (1.2mm), 31.41 (1.1mm), 41.42 (1.3mm). Diastema closure with finger spring activation towards the mesial and labial arches of the upper and lower jaws. Activation was carried out gradually at each control so that the diastema at the fourth control on teeth 33-32 (0.5 mm). Conclusion: This shows that removable orthodontic appliances are effective for closing multiple diastema with mild to moderate degrees, with patient compliance in using the appliance and the effect of using a tongue crib in reducing the patient's tongue thrusting habit.