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ASTM A36 steel has relatively low hardness and corrosion resistance, making surface treatment necessary to improve its material properties. This study aims to determine the effect of temperature and holding time variations in the pack carburizing process on the hardness, corrosion rate, and microstructure of ASTM A36 steel. The pack carburizing process was carried out using coconut shell charcoal as the carburizing medium with temperature variations of 850°C, 900°C, and 950°C and holding times of 20, 40, and 60 minutes, followed by quenching in distilled water. Hardness testing was conducted using the Rockwell B scale (HRB) method, corrosion rate testing was performed according to the ASTM G31 method, and microstructural observations were carried out using Scanning Electron Microscopy (SEM). The results showed that increasing the temperature and holding time improved the hardness and corrosion resistance of ASTM A36 steel. The highest hardness value was obtained at a temperature of 950°C with a holding time of 60 minutes, reaching 114.1 HRB. Microstructural analysis revealed the formation of a martensitic phase on the specimen surface after the carburizing process.

The consistent decline in cucumber production in Indonesia indicates limitations in conventional cultivation systems, particularly due to land scarcity and inefficient resource management. This condition has encouraged the development of hydroponic systems as a more controlled and productive cultivation alternative. This study aims to critically analyze the key factors determining the success of hydroponic cucumber cultivation and to identify the most influential management aspects in improving yield. The method employed is a literature review, examining various recent studies related to hydroponic systems, nutrient management, growing media, and environmental factors. The results show that the advantages of hydroponics lie not only in land and water efficiency but also in the ability to precisely control growth variables. However, optimal productivity highly depends on the proper integration of nutrient management, particularly the regulation of pH, electrical conductivity (EC), and nutrient balance, as well as the control of environmental factors such as temperature, humidity, and light intensity. Inaccuracy in a single component can significantly reduce plant performance, even when other factors are optimal. Therefore, an integrated approach combining nutrient and environmental management simultaneously is essential to enhance hydroponic cucumber productivity. This study confirms that hydroponics has strong potential as a strategic solution to support sustainable agriculture amid land limitations in Indonesia.

Typhoid fever is a febrile illness that commonly occurs in urban areas with poor sanitation. It is usually caused by the consumption of untreated water and contaminated food. Because the S. typhi bacterium can survive in water for days, contamination of surface water—such as wastewater, freshwater, and groundwater—serves as the primary cause of typhoid fever. The patient presented to the Emergency Department of Cut Meutia General Hospital with complaints of high fever for approximately 4 days prior to admission, which had worsened over the past 2 days. The fever fluctuated and was accompanied by chills. It worsened at night and was not influenced by weather or temperature. These symptoms were accompanied by vomiting every time the patient tried to eat, nausea, abdominal pain, headache, and weakness. The patient reported vomiting the contents of their meal every time they ate, leading to a loss of appetite. These symptoms began when the patient first developed a fever. The patient also experienced abdominal pain. Spontaneous bleeding was denied. On physical examination, the patient appeared weak but was alert and oriented. On neck examination, palpable enlargement of the thyroid glands was found on the right and left sides of the neck, measuring 2x2 cm, mobile, and soft. On abdominal examination, increased bowel sounds were noted. Vital signs were normal except for the patient’s febrile temperature. Laboratory tests revealed a Tubex blood test result of scale 4 and a positive dengue IgG serology result.

This study was conducted based on the crucial role of diesel generator engines as the primary source of electrical power on board ships, making their operational reliability essential. One of the factors influencing generator engine performance is lubricating oil temperature. Excessive lubricating oil temperature may reduce lubrication effectiveness, increase friction between moving components, and lower engine efficiency. Therefore, this research aimed to identify the causes of high lubricating oil temperature in diesel generator engines and determine appropriate corrective actions. The study employed a descriptive quantitative approach. Data were collected through direct observation, interviews, and documentation during sea practice aboard MV. CL FLANDERS from 4 July 2024 to 5 July 2025. The data were analyzed using simple linear regression to examine the relationship between generator load and lubricating oil temperature. The findings revealed that generator load had a significant effect on the increase in lubricating oil temperature. Under normal operating conditions, the lubricating oil temperature ranged from 60°C to 72°C, while under abnormal conditions it increased to between 68°C and 81°C. The abnormal rise in temperature was mainly caused by cooling system problems, particularly a dirty LO cooler, scale deposits on the sea water pump impeller, and blockage in the cooling capillary pipes. The regression equation under normal conditions was Y = 45 + 0.30X, whereas under abnormal conditions it was Y = 53.5 + 0.30X. Elevated lubricating oil temperature resulted in lower oil viscosity, higher fuel consumption, and reduced diesel generator engine performance. Therefore, regular maintenance of the LO cooler, sea water pump, and continuous temperature monitoring are necessary to maintain optimum engine performance.

Nile tilapia (Oreochromis niloticus) culture requires an efficient and low-cost feeding strategy that can support fry growth and survival. This study aimed to analyze the effects of three types of natural feed, namely silk worms, earthworms, and snails, on absolute length growth, absolute weight growth, and survival of Nile tilapia fry. The study was conducted at the Aquaculture Laboratory, Faculty of Science and Computer Science, Universitas Muhammadiyah Gorontalo, from January 31 to March 2, 2026. An experimental method was applied using a Completely Randomized Design consisting of three treatments and three replications. A total of 45 Nile tilapia fry were reared in 9 plastic containers filled with 10 L of water, with 5 fish in each container. Growth and survival data were analyzed using ANOVA at the 5% significance level, while water quality was analyzed descriptively. The results showed that the type of natural feed had no significant effect on absolute length growth, absolute weight growth, and survival. Descriptively, silk worms produced the highest length and weight growth, with values of 2.99 cm and 6.37 g, respectively. Snails produced the highest survival rate of 86.66%. Water quality remained stable, with temperature ranging from 26.3 to 26.8°C, pH from 7.6 to 7.9, and dissolved oxygen from 5.2 to 5.6 mg/L. These findings indicate that silk worms are potential natural feed for improving growth, while snails support the survival of Nile tilapia fry.

This study presents an innovation design for an Internet of Things (IoT)-based watering and liquid fertilizer control system for chili plants using a NodeMCU ESP32. The main problem addressed is the manual watering and fertilizing process, which makes it difficult for farmers to monitor soil moisture, temperature, air humidity, and light intensity in real time. The recommended method used in this draft is Research and Development (R&D) with a prototyping approach because the study focuses on designing, building, integrating, and testing an IoT device through iterative stages. The system is designed using a soil moisture sensor, DHT11, LDR sensor, two-channel relay, two 12 V DC pumps, 16x2 I2C LCD, and the Blynk Mobile application for remote monitoring and control. Sensor data are transmitted to Blynk as percentage values and plant condition statuses, while the water and fertilizer pumps can be controlled using virtual buttons. The control logic defines the optimal condition for chili plants based on soil moisture of 60-80%, temperature of 25-30°C, air humidity of 60-80%, and light intensity of 50-90%. Prototype documentation and functional testing data will be completed in the next stage.

Hypertension is a chronic condition characterized by systolic blood pressure >130 mmHg and diastolic >80 mmHg, which can lead to serious complications such as stroke and heart failure if left unmanaged. This study aims to describe the application of warm water foot soak intervention in reducing blood pressure among hypertensive patients in the Dongkelan Kauman area. This was a descriptive study with a case study approach involving three elderlies with hypertension. The intervention was conducted for 20 minutes daily using warm water at a temperature of 38-40°C for three consecutive days. Data were collected through interviews and blood pressure measurements using a tensimeter before and after the intervention. The results showed a decrease in blood pressure in all three subjects after routinely implementing the intervention. The highest systolic reduction reached 15 mmHg, while the average diastolic reduction was 5 mmHg. Physiologically, warm water stimulates blood vessel vasodilation, which facilitates blood flow and reduces muscle tension. The study concludes that warm water foot soak therapy potentially effective as a non-pharmacological complementary intervention for controlling blood pressure in elderly patients with hypertension.

Hypertension is a chronic condition characterized by systolic blood pressure >130 mmHg and diastolic >80 mmHg, which can lead to serious complications such as stroke and heart failure if left unmanaged. This study aims to describe the application of warm water foot soak intervention in reducing blood pressure among hypertensive patients in the Dongkelan Kauman area. This was a descriptive study with a case study approach involving three elderlies with hypertension. The intervention was conducted for 20 minutes daily using warm water at a temperature of 38-40°C for three consecutive days. Data were collected through interviews and blood pressure measurements using a tensimeter before and after the intervention. The results showed a decrease in blood pressure in all three subjects after routinely implementing the intervention. The highest systolic reduction reached 15 mmHg, while the average diastolic reduction was 5 mmHg. Physiologically, warm water stimulates blood vessel vasodilation, which facilitates blood flow and reduces muscle tension. The study concludes that warm water foot soak therapy potentially effective as a non-pharmacological complementary intervention for controlling blood pressure in elderly patients with hypertension.

Travertine is a non-marine carbonate rock precipitated from calcium- and bicarbonate-rich waters, commonly associated with hot springs, streams, and lakes in tectonically active regions. This study presents a systematic literature review of travertine deposit characteristics, encompassing mineralogical composition, geochemical signatures, petrographic textures, morphological types, isotopic properties, biotic–abiotic controls on formation, early diagenesis, and petrophysical implications. The synthesis indicates that travertine is predominantly composed of calcite, with aragonite forming under conditions of elevated temperature, high Mg/Ca ratios, and rapid CO₂ degassing. Travertines display exceptional textural diversity, ranging from abiotic crystalline crusts to microbially mediated fabrics such as shrub, peloidal, and stromatolitic structures. Major morphologies include fissure ridges, mounds, terraces, cascades, and slopes, strongly governed by tectonic setting, topography, hydrology, and substrate geology. Stable isotopes (δ¹³C and δ¹⁸O), strontium isotopes, trace elements, and REE patterns effectively constrain fluid provenance and distinguish thermogene from meteogene travertines. Microbial activity plays a crucial role in biomineralization, influencing precipitation rates, crystal morphology, and lamination patterns. Early diagenetic processes occurring during active deposition may significantly modify primary fabrics and geochemical signals. Travertine petrophysical properties exhibit distinctive porosity–velocity relationships, making them valuable analogues for subsurface carbonate reservoirs. This review highlights that travertines record complex interactions among physical, chemical, biological, and geological processes and hold significant value for paleoenvironmental reconstruction and carbonate reservoir studies.

The oil and gas industry requires efficient initial processing to separate reservoir fluids into oil, gas, and water phases. The Separator Unit is the main facility that plays a vital role in the surface facility production stage. This study aims to evaluate the type of separator used, identify control components, and understand the working principles and operational procedures of separators in the Main Production Facility (MPF) area. The methodology used is direct observation and literature studies during the implementation of practical work in July 2024 at PT. Citic Seram Energy Limited, Seram Non Bula Block, Maluku. The observation results show that the type of separator used is a Horizontal Three Phase Separator with tag codes 03-V-001A and 03-V-001B operating alternately. The separation process is carried out based on differences in fluid density utilizing gravity, supported by internal components such as deflector plates, mist extractors, weirs, and straightening vanes. Separator operation is maintained at an operating pressure of around 55 psig to ensure optimal separation efficiency and work safety. The conclusion of this study indicates that effective separator operation requires stable pressure and temperature control as well as routine maintenance to prevent sediment buildup and maintain product quality.

Modern infrastructure development often involves the use of mass concrete in large structural elements such as pile caps and foundations. However, massive concrete volumes trigger a significant temperature increase due to the heat of hydration that is difficult to dissipate, posing a risk of thermal stress and structural cracking. This study aims to analyze the temperature rise behavior of mass concrete and evaluate the effectiveness of combining chilled water and fly ash substitution in minimizing these thermal cracking risks.The research method employs a quantitative approach through laboratory testing at PT Adhimix RMC Plant Kaligawe. Specimen blocks measuring 40 x 40 x 100 cm were divided into three variations: normal concrete (BN), concrete with chilled water and 15% fly ash (BAF), and concrete with 25% fly ash (BF). Temperature was monitored using thermocouples at the core and surface for 14 days, then validated using the Portland Cement Association (PCA) formula. The results indicate that the integration of chilled water with 15% fly ash and the use of 25% fly ash significantly controlled extreme temperature surges at the 5th hour. The combination of chilled water and 15% fly ash produced the lowest core temperature of 37.3°C, far below the control concrete which reached 62.4°C. This proves that the combination of precooling methods and fly ash substitution is effective in reducing the heat of hydration during the early hardening period, although the use of 25% fly ash was found to be more stable in maintaining mass concrete temperature.

Vannamei shrimp (Litopenaeus vannamei) is one of the most important aquaculture commodities with high economic value and strong market demand. The transportation of broodstock shrimp is a critical stage that may affect survival due to decreased oxygen levels and water quality deterioration. High stocking density during transportation can accelerate oxygen depletion and increase metabolic waste, leading to higher mortality. This study aimed to determine the effect of different packing densities on the survival rate of broodstock shrimp during 12 hours of transportation. The experiment used four treatments with densities of 6, 8, 10, and 12 shrimp per bag, each with six replications. Observed parameters included temperature, dissolved oxygen (DO), and survival rate. The results showed that lower stocking density produced higher survival rates, with the best result obtained at 6 shrimp per bag. Water quality remained within acceptable limits, although oxygen levels decreased with increasing density. Therefore, proper stocking density is essential to maintain shrimp survival during transportation.  

Rice plants (Oryza Sativa L.) are the main staple food commodity in Indonesia, as most of the Indonesian population relies on rice as their primary food. One of the causes of low rice production in Indonesia is that farmers generally cultivate rice improperly, such as in land preparation or land selection. Land suitability in rice cultivation greatly affects crop productivity. A process that can support decisions regarding rice land suitability is the development of a Decision Support System (DSS) website using a combination of the Simple Additive Weighting (SAW) method and the Technique for Order Performance of Similarity to Ideal Solution (TOPSIS). This combination is performed by taking the average (µ) of the final results from the SAW and TOPSIS methods. The final scores of each method are calculated separately, and then the average (µ) of these two results is taken to obtain the final ranking of the alternatives. The data used to determine the suitability of rice land is based on five criteria: soil type, soil pH, rainfall, temperature, irrigation and water supply. The alternative data used in the study includes six alternatives: Sungai Kunjang, Sambutan, Samarinda Utara, Palaran, Loa Janan Ilir, and Samarinda Seberang. The aim of this research is to provide information on alternative solutions to farmers or farmer groups in determining rice land suitability. The results of the combination of the SAW and TOPSIS methods show that the alternative with the highest final score is Samarinda Utara (A3), with a final score of 0.7337. Meanwhile, the alternative with the lowest final score is Sambutan (A2), with a final score of 0.4402.

Vaname shrimp (Litopenaeus Vannamei) is one of Indonesia's fishery commodities with high economic value. Vaname shrimp production in Indonesia continues to increase. However, obstacles sometimes arise in cultivation activities, such as the emergence of shrimp diseases and poor water quality. High stocking density and shrimp feeding can cause a decline in water quality. In addition, pond water quality is influenced by pond location and the surrounding environment, such as agriculture, settlements, mangroves, and the sea. This causes ponds to have different water qualities. One of the diseases that often attacks shrimp farming is caused by the bacterium Vibrio sp. The abundance of Vibrio sp. bacteria is closely related to pond water quality and the environmental conditions around the pond. The methods used were TPC testing and multiple linear regression testing. Based on the results of the study, the abundance of Vibrio sp. bacteria in pond A was the highest at 8.3 x 102, and pond C had the lowest at 3.1 x 102. Water quality testing in three different ponds showed safe limits for cultivation, except for nitrite testing. Based on the simple linear regression test, the water quality parameters that significantly affect the abundance of Vibrio sp. bacteria are pH, temperature, and nitrite.  

Extreme changes in water quality, whether in the form of temperature fluctuations, exposure to detergents, pH decreases due to acetic acid, or changes in salinity, have the potential to cause complex physiological disorders in tilapia. The research aims to analyze the physiological responses of tilapia to changes in water quality in extreme environments given exposure to Temperature, Detergent, Acetic Acid, and Salinity. This research was conducted at the Wet Laboratory of Achmad Yani University, Banjarmasin. The physiological parameters observed included fish behavior, respiratory frequency measured by the number of openings and closings of the operculum per minute, gill condition, and mucus production on the body surface. Exposure to extreme environments in the form of high temperatures, detergents, acetic acid, and salinity caused physiological disorders in tilapia with varying levels of response. Exposure to acetic acid had the most rapid and severe impact, characterized by damage to scales and fins, impaired movement to the point of fish capsizing, and unstable breathing, while detergent and temperature triggered changes in external organs, heart rate, and behavior. Salinity treatment primarily affected osmoregulatory function as seen from increased respiratory frequency and heart rate. All treatments showed that extreme changes in water quality can cause significant physiological stress in tilapia.

Complementary therapy has recently become an important issue in many countries. Its use has increased due to several factors, including personal beliefs, cost considerations, the side effects of chemical medications, and expectations of recovery. One of the complementary therapies that is often chosen is warm water foot soaking combined with foot massage. This therapy has the potential to reduce blood pressure through relaxation mechanisms and peripheral vasodilation, which have been supported by scientific evidence.This study aimed to analyze the application of Evidence-Based Practice (EBP) of warm water foot soaking and foot massage therapy in hypertensive patients within nursing care. The method used was an EBP-based case study design involving three patients with hypertension. The intervention consisted of warm water foot soaking using approximately 2 liters of water at a temperature of 38–40°C combined with foot massage, administered once daily for three days. Blood pressure was measured before and after the intervention.The results showed a decrease in blood pressure: Mrs. S from 170/100 mmHg to 150/80 mmHg, Mrs. L from 170/80 mmHg to 150/80 mmHg, and Mr. F from 165/90 mmHg to 130/70 mmHg. Warm water foot soaking and foot massage were effective as non-pharmacological interventions to reduce blood pressure and improve comfort in patients with hypertension. ase study design involving three patients with hypertension. The intervention consisted of warm water foot soaking using approximately 2 liters of water at a temperature of 38–40°C combined with foot massage, administered once daily for three days. Blood pressure was measured before and after the intervention.The results showed a decrease in blood pressure: Mrs. S from 170/100 mmHg to 150/80 mmHg, Mrs. L from 170/80 mmHg to 150/80 mmHg, and Mr. F from 165/90 mmHg to 130/70 mmHg. Warm water foot soaking and foot massage were effective as non-pharmacological interventions to reduce blood pressure and improve comfort in patients with hypertension.

Hypertension is a global health issue and major risk factor for cardiovascular disease, requiring lifelong medication. In addition to pharmacological treatment, healthy lifestyle changes and non pharmacological therapies such as warm water foot soaks, can help prevent complications by inducing vasodilation to lower blood pressure. This study aims to describe nursing care for hypertensive patients, focusing on the application of warm water foot soaks to reduce blood pressure in an inpatient setting. Methods a descriptive case study approach was used three hypertensive respondents. The intervention involved 15 minute warm water foot soaks at a temperature of 39-40°C, conducted once daily for three days. Data were collected using digital sphygmomanometers and observation sheets, with measurements taken before and after the intervention. Results, after the therapy, all respondents showed an average reduction in blood pressure, with systolic pressure decreasing by 6,6 mmHg and diastolic by 2,3 mmHg. Respondents also reported felling more relaxed and experiencing lighter sensations in their legs. Conclusion, warm water foot soak therapy is an effective, safe, and cost efficient non pharmacological intervention for hypertensive nursing care, suitable for implementation by both nurses dan families.

Whiteleg shrimp (Litopenaeus vannamei) is a leading commodity in aquaculture in Indonesia due to a number of advantages such as disease resistance, rapid growth, high survival rate, and feed conversion efficiency. Whiteleg shrimp contributes significantly to Indonesian fisheries exports, reaching 38.98% in 2021. To meet high market demand, increasing the productivity and quality of whiteleg shrimp is very important, where the quality of the shrimp is influenced by the quality of the fry. Good management, including selecting quality broodstock, proper handling of eggs and nauplii, and maintaining optimal water quality, is very important in producing quality whiteleg shrimp fry. This study aims to determine the effect of temperature on the growth length and life expectancy of whiteleg shrimp nauplii. The study was conducted using a completely randomized design with three different temperature treatments (26°C, 29°C, and 32°C). The whiteleg shrimp nauplii used had an average size of 328.24mm obtained from PT. Delta Windu Purnama Situbondo. The water quality parameters used are Temperature, pH, salinity, and DO. Delta Windu Purnama Situbondo. Data were analyzed using SPSS 16.

The transportation of tiger shrimp postlarvae (Penaeus monodon) in aquaculture practice is a critical stage as it may induce physiological stress that directly reduces survival rate. Salinity, as a water quality parameter closely associated with osmoregulatory processes, is a key determinant of success in closed wet system transportation. The present study was designed to examine how varying salinity concentrations influence the survival percentage of PL 10 tiger shrimp postlarvae subjected to closed wet transport conditions, as well as to identify the most suitable salinity range for such transport. A Completely Randomized Design (CRD) was employed with five salinity levels as treatments — 10, 15, 20, 25, and 30 ppt — each replicated five times. Each experimental unit contained 1,500 postlarvae in 1 L of oxygenated water packed in plastic bags and transported for approximately 3 hours. The main parameter observed was survival rate (SR), while supporting parameters included temperature, dissolved oxygen (DO), and pH. Statistical evaluation included the Kolmogorov–Smirnov normality test, Levene’s test for variance homogeneity, one-way analysis of variance (ANOVA), and Duncan’s Multiple Range Test (DMRT) at a significance level of α = 0.05. Results showed that salinity differences had a highly significant effect on postlarvae survival rate (Sig. = 0.000 < 0.05). The 25 ppt salinity treatment produced the highest survival rate of 99.64%, while 10 ppt resulted in the lowest at 63.78%. The measured water quality variables — temperature, dissolved oxygen, and pH — did not exert a statistically significant effect on postlarvae survival throughout the transport period.

Vegetables are an important horticultural commodity in fulfilling community nutritional needs; however, their consumption level in Indonesia remains relatively low, necessitating efforts to increase production. Spinach (Amaranthus sp.) is a promising vegetable due to its short growth cycle, ease of cultivation, and high nutritional value. Limited agricultural land, particularly in urban areas, poses a major constraint to conventional cultivation, thereby encouraging the adoption of alternative technologies such as hydroponics. The hydroponic system, especially the Nutrient Film Technique (NFT), offers efficient use of land and water while enabling better control of plant growth. This review aims to identify hydroponic cultivation techniques for spinach in greenhouse conditions and to analyze factors influencing its success, including nutrient concentration, growing media, pH, temperature, and light intensity. The findings indicate that optimal nutrient concentration ranges from 410–900 ppm, supported by proper environmental and pH management to enhance vegetative growth. The implementation of the NFT system improves production efficiency, resulting in more uniform, cleaner, and higher-quality yields. Nevertheless, challenges remain, including nutrient management, environmental fluctuations, and pest and disease risks. Therefore, proper and sustainable system management is essential to ensure successful hydroponic spinach cultivation.