bluuebunny/crossref_metadata_2025 huggingface dataset:
Survey of Insects Associated with some Species of Cucurbitaceae in Iraq
Authors: Al-Saffar H H , Augul R S , Ali Z A A
Published: February 2024

Due to the spread of insect pests that destroys the crops belonging to the Cucurbitaceae family and led to deterioration in crop productivity in Iraq due to various reasons, the most important of which is Climate fluctuation and extreme weather events have a major impact on this problem. So, this paper was proposed to identify those species pests and prevalence. Insects were collected during the period from March 1. 2022 to October 30, 2022 from the several regions of Iraq, including: Baghdad, Babylon, Basra, Karbala, Wasit, Diyala, Saladin, and Duhok Provinces. The results showed 19 important species under 17 genera with 13 families, and five orders. The most common synonyms and distribution of species, as well as the plant hosts were provided; and the scientific names have been corrected according to the recent references. The date and localities of the specimens’ collection were presented. In conclusion, the species ofDacus frontalisBeecker, 1922 andD. ciliatesLoew, 1862 were the most abundant pests in studied regions, especially Diyala, Wasit, and Baghdad Provinces. In contrast toCarpomya pardalina(Bigot, 1891), which was the least prevalent among the recorded species.
Regression coefficient of semen characteristics of buffalo bulls on seminal plasma proteins
Authors: Musa K S , Abdulkareem T A
Published: February 2024

An experiment was carried out to explore the regression coefficients (RC) of semen characteristics on seminal proteins of buffalo bulls. SDS-PAGE resolved seminal proteins. A life sperm (LS) percentage exhibited a negative and significant RC on PF1 (111.5 ± 18.0 kDa), PF4 (36.13 ± 3.33 kDa), and PF5 (28. 88 ± 3.26 kDa) proteins, namely -0.13, -0.63 and -0.69 % / kDa respectively. A sperm acrosome integrity (SAI) percentage exhibited a pronounced negative RC on PF1 and PF2 (87.63 ± 16.5 kDa), -0.13 and -0.14 % / kDa, respectively. A negative RC was noticed in SAI percentage on PF4 (-0.61 % / kDa) and PF5 (-0.60 % / kDa) proteins. A pronounced positive RC was shown for total sperm abnormalities (TSA) on PF1 proteins (0.02 % / kDa). In conclusion, some semen attributes had a negative RC on some seminal proteins. In conclusion, some semen attributes had a negative RC on seminal proteins. These provide us with a good tool for early predicting the buffalo bull’s fertility to reduce the economic losses of male infertility and enhance the developmental sustainability of buffalo production in Iraq.
The Effect of seaweed (Eucheuma cottonii) extract and duration of soaking on reduction of Copper (Cu) level in Freshwater Mussel (Pilsbryoconcha exilis)
Authors: Dewinta A F , Susanti A , Susetya I E
Published: February 2024

Freshwater Mussels (Pilsbryoconcha exilis) are filter-feeder animals that have eating habits by filtering food in the water, making it possible that heavy metal copper (Cu) will accumulate in the body of the mussel. One type of seaweed that can absorb heavy metals is Eucheuma cottonii because it contains iota carrageenan (65%) which is a sulfated polysaccharide containing hydroxyl groups and carboxyl groups capable of retaining and accumulating heavy metals. In addition E. cottoni as a biosorbent in the aquatic environment. This research aims to determine the effect of extract concentration and the best soaking time in reducing copper (Cu) levels. This research was conducted from April to May 2023. In this study, the concentrations used were 6%, 10%, and 14% with a period of 45 minutes, 90 minutes, and 135 minutes. The results showed that the concentration of 14% extract with a soaking time of 135 minutes showed the highest decrease in copper (Cu) levels of 1.298 mg/kg or 87.10% and the lowest decrease in copper (Cu) metal levels at a concentration of 6% with a soaking time of 45 minutes of 0.442 mg/kg or 29.68%.
Purification of used cooking oil using natural corn cob and carbon corn cob as adsorbent with batch operation
Authors: Haryanto B , Hutagaol L N , Sianturi N C , Fazira M , Sitorus J , Alexander V
Published: February 2024

Adsorption is one of the processes used to purify used cooking oil by using adsorbents from natural and carbonized corn cob as part of sustainability. The adsorption process is chosen because it is more economical, efficient, relatively affordable cost, and can be regenerated. This study was conducted in batches to observe changes in the quality of used cooking oil at certain time intervals and to determine the modeling of adsorption kinetics on natural corn cob and carbonized corn cob adsorbents. The sample of this study is 100 ml of used cooking oil with adsorbents in the form of natural corn cob and carbonized corn cob with a mass of 3 grams and a particle size of 70 mesh. This study’s best adsorption result is corn cob carbon adsorbent. This can be seen from the final turbidity value of 37.3 NTU compared to the natural corn cob adsorbent of 37.6 NTU. This study found that the adsorption process that occurs has chemical interactions as evidenced by second-order pseudo-modeling, which has a correlation coefficient close to one.
Low concentration 1-MCP limit ripening process of mango cv. ‘gedong gincu’ during low temperature storage
Authors: Setiawan C K , Sari K F , Utama N A
Published: February 2024

Mango fruit still ripens and senesces after harvest. The presence of ethylene will shorten the shelf life of mangoes during long transportation processes. The purpose of this research is to find out how long the ‘gedong gincu’ mango (Mangifera indica L.) can be kept at 15°C after being treated with 1-methylcyclopropene (1-MCP). This study conducted experiments in the lab using a completely randomized approach with a single factor that included treatment with and without 500 ppb 1-MCP. Both was kept at 15°C for both sessions. Weight, color, hardness, total dissolved solids, total titrated acid, and chilling injury score were measured in this study. Analysis of data will be conducted using a t-test at α = 5% using Microsoft Analysis Toolpak. The study found that adding 1-MCP to mango cv ‘gedong gincu’ had a significant effect (p<0.05) on its color change, hardness, total titrated acidity, and chilling injury score during storage at low temperatures. This suggests that 1-MCP may be able to delay the ripening process by ethylene and extend the shelf life of ‘gedong gincu’ mangoes when stored at 15°C, thereby contributing largely to food loss prevention.
Consumer perception of decocted coffee leaf tea originated from different altitude
Authors: Fibrianto K , Sholihah N , Bimo I A
Published: February 2024

It is commonly known that plantation location influences the composition of the coffee component as well as the leaves. Therefore, it was expected that the difference location will also affect the quality of decocted one. In this current study, effect of plantation location is investigated on Arabica and Robusta coffee leaf tea. Two different coffee plantations were chosen as the region of observation (560 ASL and 1700 ASL). All the coffee leaf tea was brewed by decoction method, in which sensorially optimized by Just about Right (JAR) method. The sensory attributes of concern were included sweet, sour, bitter taste and astringent mouth-feel. Considering consumer preference on the brewed coffee leaf tea, the decoction brewing condition were set on 95°C for 5 minutes. Additionally, coffee leaf tea grown at higher altitudes exhibits significantly greater total phenolic content (TPC) and antioxidant activity (p < 0.05). Not only does this tea have higher TPC and antioxidant activity at higher altitudes, but it also shows superior consumer sensory acceptability. This may be supported by the fact that higher altitude coffee leaf tea has more diverse sensory driver components than that of lower altitude coffee leaf tea as suggested by LC-MS.
Encapsulation of anthocyanins from purple yam extract (Dioscorea alata, L.) flour using maltodextrin-whey protein isolate
Authors: Tamaroh S , Sari Y P
Published: February 2024

Anthocyanins are antioxidant compounds that can act as anti-inflammatory, anti-viral, and prevention of diabetes. In Indonesia, many foods are rich in anthocyanin compounds, including purple yam tuber (Dioscorea alata L.). Anthocyanins are easily damaged by exposure to light changes in pH and temperature. Encapsulation can increase the nutritional value, color, shelf life, and bioavailability and stability of anthocyanin. The encapsulant such as maltodextrin and whey protein isolate were chosen because they were affordable and can protect the anthocyanin. Anthocyanin extract from purple yam flour were prepared to be incorporated in nanoencapsulation. Encapsulation were prepared with a ratio of maltodextrin and whey protein isolate = 1 : 3 (w/w) with anthocyanin extract of 5, 20 and 30%. Each formulas were dried by a spray drier. The results showed that the treatment using 30% anthocyanin extract resulted in the best nanoencapsulation. The encapsulation had anthocyanin content was 77.72 mg/100 g, total phenolic content was 510.07 mg GAE/100 g (db), antioxidant activity was 24.06 % RSA, color L* = 79.15, a * = 5.58, b* = -0.39. Therefore, anthocyanin extract encapsulation can be produced successfully by this method.
Food estate management strategy in Humbang Hasundutan Regency, North Sumatra Province
Authors: Syahputra O H , Anggraini N , Irmansyah T
Published: February 2024

Food Estate is the concept of developing agricultural production on a wide scale, as an effort to create national food security by extensifying land as a form of large-scale agriculture that relies on the agricultural industry. Data were obtained from questionnaires through the Purposive sampling method, identification of internal and external factors can be carried out so that a food estate management strategy can be formulated using a SWOT analyst. Based on internal factors, the most important strength is the commitment of off-takers (cooperation, use of certified seeds, production targets, demplot, farm business analysis, and drip irrigation systems) with a score of 0.43, and the use of technology and increasing public knowledge about the horticultural system with a score of 0.43. While the variable that has the highest weakness is that land cannot be traded with a score of 0.42. The results of an external analysis obtained the opportunity variable with the highest value, namely the production cost borne by the off taker, and the agreed crop price between the off taker and farmers with a score of 0.44, and then external variables in the form of threats, namely pests and high rainfall with a score value of 0.42.
The effect of NPK fertiliser on oil palm coefficient as a baseline water management during the nursery phase
Authors: Sigalingging R , Sumono  , Pratiwi O W
Published: February 2024

The Indonesian government views the oil palm industry as a promising sector for poverty alleviation. The germination process of seeds is influenced by water, requiring careful management. This study investigated the impact of NPK application and NPK fertiliser on the crop coefficient value of Tenera variety oil palm seedlings. The entisol soil used had a sandy clay texture, with sand comprising 81.00% of the soil composition. The soil texture, organic matter, bulk density, particle density, porosity, evapotranspiration, potential evaporation, percolation, moisture content at field capacity, and oven-dried root weight were measured with and without fertiliser to 50 oil palm trees at 3 to 6 months of age. The results show that NPK application has affected oil palm’s crop coefficient and growth. The highest dry root weight and plant coefficient obtained without fertiliser and with fertilisers at six months were 24.76 gr and 33.89 gr, 0.626 and 0.65, respectively. Root biomass, a sign of plant health and nutrient uptake, shows fertilization’s long-term effects. Six-month-old plants, especially fertiliser ones, have more extensive root dry weights, indicating persistent nutrition uptake and long-term resistance. Nutrient management is crucial to agricultural productivity, affecting the current crop and future growth phases.
NIR Spectroscopy application to determine the carbohydrate and lipid content in green bean coffee
Authors: Ayu P C , Rindang A , Sebayang N U W
Published: February 2024

Coffee flavor is influenced by the chemical concentration including the carbohydrate and lipid content. Determination of the chemical content is still using the chemical method that spend time, expensive and destructive, then a suitable method which is fast and non destructive is required especially to fulfill the needs of coffee industries. This study aimed to apply NIRS method to determine the carbohydrate and lipid content from Indonesia green bean coffee from several origin to increase the data distribution, NIR wave of 1000-2500 nm, followed by determination of the carbohydrate and lipid content using chemical method. After that, NIR data pretreatment using multiple scatter correction (MSC), first and second derivative of savitzky golay, normalization and the combinations then calibrate both the spectra and chemical data by Partial Least Square (PLS) method. Result showed that NIR spectroscopy can be used to determine the carbohydrate and lipid content in green bean coffee could be seen by the high coefficient correlation, RPD and consistency value, while the CV is lower than 2.
Design of coffee roaster with controlled temperature system to maintain the sustainability of coffee roasting process
Authors: Ayu P C , Machrizailani M R , Rohanah A , Sinamo K N , Sebayang N U W
Published: February 2024

One of the most important process in producing coffee beverage is the roasting stage. Nowadays, roasting process is done using mechanic process by giving high temperature to coffee beans. However, the temperature is not controlled and the capacity tend too high or low, expensive and need a qualified coffee roaster to do this stage, which is not suitable for small and micro bussiness. This research aimed to answer those problems by designing a roasting machine that could control the temperature with a capacity of 4 kg per process. Result showed that the roasting machine could roast the coffee bean in 52 minutes to achieve the medium to dark roast level, and it is suitable for the small and micro bussiness according to the roasting profile and from the economic analysis this machine is feasible. Moreover, this coffee roaster is energy efficient and could provide a better livelihood for the user to produce the roasted beans even with no roasting experience.
Utilization of filter variation and FABA addition in biogas production from palm oil liquid waste to produce electricity
Authors: Raju  , Rohanah A , Simanullang S N A
Published: February 2024

Industrial waste processing is the best step to create a healthy environment. Industrial waste has the potential to be used as biogas, one of which is palm oil liquid waste. Biogas is produced from the fermentation process of palm oil liquid waste with other materials such as sawdust and boiler ash assisted by EM4 as an activiator for bacteria in fermentation. The purpose of this research was to get the best data on the electric power of the variations and replications carried out. Biogas converted to electricity with 3 variations with 3 replication. P1 is 50% biogas and 50% LPG gas filtered using a sulfur filter, P2 is 50% biogas and 50% LPG gas filtered using a boiler scale filter, and P3 is 50% biogas and 50% LPG gas filtered using a combination filter of sulfur and boiler scale. The fermentation process produces biogas of 70,519.167 cm3 at 21 days. The highest average electricity is 242 watts at a sulfur filter, 176 watts at a sulfur and boiler cale filters, and 168,776 watts at a boiler scale filter.
Sustainability of agribusiness institutions (case study on horticultural agribusiness farmer groups in Bantaeng Regency)
Authors: Akbar  , Jumiati  , Rumallang A
Published: February 2024

Institutional has become very valuable in the implementation of sustainable agricultural development. The main objective of this study was to examine the dynamics of the system and the strategy of institutional sustainability of farmer groups in horticultural agribusiness in Bantaeng. Then, the collected data were processed and analyzed using qualitative descriptive with Brinkerhoff institutional sustainability analysis approach. The results showed that the dynamics of the system in changing inputs through the process to produce outputs consistently improved over time conditioning the institutional sustainability of farmer groups in the development of horticultural agribusiness in supporting sustainable agriculture. The contingency power of farmer groups is determined by their ability to respond to the dynamics of the work environment, as well as the political-economic environment through a combination of strategies, both mechanical, adaptive, reactive, and interactive carried out simultaneously or partially to achieve its sustainability level. The effectiveness of institutional sustainability strategies to support system capacity in improving farmer group performance, is indicated by its ability: (1) Creating competitiveness by maintaining product quality; (2) Handling and utilizing waste through innovation and development of product diversification so as to increase income, value added and environmentally friendly; and (3) Creating satisfaction for consumers.
ICT-based agricultural extension literacy and the needs for agriculture development and sustainability: a case study of rice farmer in Aceh
Authors: Zikri I , Firda I , Hamid A H , Susanti E
Published: February 2024

In the current era of technological development, agricultural extension considers as one of the determinant factors for the smoothness and success of agriculture development and sustainability. This study aims to determine the literacy and the needs of lowland rice farmers towards agricultural extension using social media and its contributing factors. The study employs a questionnaire survey using simple random sampling of 48 farmers located in Kecamatan Delima, Pidie –one of the central paddy fields in the region. Data analysis used a descriptive approach and binary logistic regression analysis. The study finds that almost half of respondents had a high literacy, while 29.5 percent were moderate, and only 12.5 percent were low. Related to needs, about two-thirds of respondents stated the urgency of interest and need of using ICT-based media as a means for outreach as a medium of information, training, and satisfaction. Statistically, access to information and farmer age affect the need for information and satisfaction, while educational attributes influence the need for training. The employment of the current and latest technological media as a learning tool and diffusion of innovation is necessary for estimable and admirable alternative changing behavior in agricultural development.
Estimation of agricultural productivity loss due to soil loss in Buayan-Malungon River Basin, Philippines: A foundation for watershed protection and agricultural development
Authors: Mag-Aso J R , Vista A B , Garcia F G N
Published: February 2024

The Buayan-Malungon River Basin (BMRB) is currently experiencing intolerable soil loss due to improper agricultural practices, and unsustainable land uses. This problem disrupts important ecosystem services such as provisioning, regulating, cultural, and supporting. This article provides an estimate of the agricultural crop productivity losses due to soil loss. The study estimates productivity losses through regression analysis by using nitrogen (N) fertilizer as a proxy for soil quality. The result revealed that N-fertilizer had a significant effect on corn yield. The predicted soil loss in BMRB in 2020 reached 41,308 tons/ha. Hence, the total soil loss cost in the river basin reached PhP 218,023,624 in 2020. This cost can be minimized if farmers practice a contour farming system as it helps to improve soil quality and control soil loss, which leads to sustainable farming and environmental sustainability.
The role of village owned enterprises in the development and sustainability of the agrotourism sector (A case study of agrotourism in Karanganyar Regency, Central Java)
Authors: Lestari E , Rusdiyana E , Sugihardjo  , Setyowati R , Widiyanto  , Santoso I S
Published: February 2024

Playing an important role in lifting the agricultural sector, agrotourism increases farmers’ income. Group involvement is required in this activity, particularly in its management such as Village-Owned Enterprises (BUMDes). This study aims to determine the role of BUMDes in the development of agrotourism in Karanganyar Regency. The research method used in this study is a qualitative descriptive method by describing, explaining and answering in detail the problem to be studied. Ngargoyoso District was chosen deliberately as the research location because this district is an agrotourism center in Karanganyar Regency. Data collection was conducted through FGD, direct interviews as well as documentation and field observations. This study found that BUMDes have not played its role optimally in the development of agrotourism, because most of the agrotourism are privately owned. BUMDes strives to offer the concept of professional management but is still constrained by community trust. The village government provides support by providing funding assistance in the licensing process. The maintenance of tourist environment is an effort taken by community and tourism managers to maintain the cleanliness and comfort of tourist areas so that the community can carry out economic activities continuously and tourism sustainability can be achieved.
The effect of grain price stability and capital availability on gen-z’s interest in farmer entrepreneurship in Serdang Bedagai Regency
Authors: Ananda H , Subhilhar  , Harahap R H , Kusmanto H
Published: February 2024

The reluctance of the majority of Indonesians, especially Gen Z, to enter the agricultural business is not only due to social factors but also price stability that can change rapidly due to global factors, and when viewed in terms of capital, it is also challenging to access startups in the high-risk agricultural sector. The objective of this research is to gain insights and explore the effect of grain price stability and capital availability on the interest of gen-z in farmer entrepreneurship in the Serdang Bedagai regency. The research employs a quantitative methodology and utilizes an associative approach. The research took place in the Serdang Bedagai regency, Sumatera Utara province, through the distribution of research questionnaires directly to gen-Z. The researchers made gen-Z of Serdang Bedagai regency as the study population, by taking a sample of 96 respondents and using purposive sampling in sampling techniques. The results showed that the stability of grain prices and the availability of capital had a significant partial and simultaneous effect on Gen-Z’s interest in farmer entrepreneurship. And it was found that the stability of grain prices (X1) and the availability of capital (X2) affected the interest of gen-z in farmer entrepreneurship (Y) by 40.6%.
The red chili supply chain management produced from coastal land based on food supply chain network to realize agriculture sustainability in Bantul Indonesia
Authors: Susanawati  , Pertiwi A
Published: February 2024

Agricultural commodities from coastal land farming such as chilies can be used to realize sustainable agriculture, so this study aims to describe the red chili supply chain and analyze the supply chain management of red chili produce coastal land. Farmer sampling was carried out in stages starting from the subdistrict, village, hamlet, and farmer levels. Farmer respondents were taken deliberately as many as 75 people. Sampling after farmers was carried out using the snowball sampling method with a total of 69 respondents. Descriptive analysis techniques to analyze the red chili supply chain and use food supply chain network framework to analyze supply chain management. The results showed that the red chili supply chain has three chains formed by 5 actors. The selection of partners with criteria of high price, subscription, trust, and easy sales with responsible and mutually open performance. All supply chain actors make unwritten agreements. The transaction system used is auctions and scales with most delayed payments and cash. Government support is only given to farmers and auction markets in the form of infrastructure. Supply chain collaboration that occurs openly and reciprocally with context of communication related to price, quality, quantity, type of chili, and stock availability.
Optimization model growth and equalization of farmer’s income in the rotiklot dam service area on the border area of Indonesia-Timor Leste
Authors: Taena W , Sipayung B P , Blegur F M A , Klau A D
Published: February 2024

The study aims to analyze optimization models of growth and income distribution. The study used a survey method in Fatuketi Village, Kakuluk Mesak District as the Rotiklot Dam service area, with a sample of 300 respondents. Data analysis uses a multi-objective linear programming model for growth and equal distribution of agricultural income. The results of the analysis show that an income of IDR 11,576,192.00 per year is an income that optimizes growth and income distribution. Optimizing growth and equal distribution shows that the average income of farmers in the first planting season was IDR. 4,132,108 and IDR. 7,444,084 in planting season II. The marginal land used is 300 ha with the volume of water needed to meet all plant needs as much as 1,986,565.16 m3. Agricultural income can still be increased for the third planting season because there is still excess water of 948,434.84 m3.
SOI Based metasurface for broadband perfect reflection in visible spectrum
Authors: Ankit  , Kishor Kamal , Sinha Ravindra Kumar
Published: February 2024

We propose modeling and design of a low-loss all-dielectric metasurface (DM), comprised of Silicon on Insulator (SiO2) substrate to demonstrate a perfect reflector in the visible spectrum. The proposed metasurface unit cell consists of V and W shapes arranged in a mirror image configuration, with nanometre-sized gaps (g) between them. A narrow peak with a nearly 100% reflectance and a broad perfect reflectance spectrum is observed within the visible region (400–700 nm) of the electromagnetic spectrum. The effective electromagnetic parameters were also analyzed for electric and magnetic dipole resonance. The electric and magnetic field distributions at the resonant wavelength were also analyzed for the proposed structure. By altering the gap region ‘g’, the thickness of the dielectric Silica layer (ts
), and the Si resonator (t
m), the proposed structure exhibits tunable characteristics. We have successfully illustrated the consistent position of the scattering parameter’s response, regardless of the structure’s rotation, concluding the homogeneity of the designed structure across the entire visible spectrum. The all-DM exhibits a unique combination of features, including a distinct and wide reflectance spectrum as well as a tuned and enhanced electric field which makes it an ideal platform for the applications in filters, color printing, low-loss slow-light devices, and nonlinear optics.
Application of the fractional Fourier transform for decryption in experimental optical cryptosystems
Authors: Vargas-Castrillon Carlos , Velez-Zea Alejandro , Barrera-Ramírez John Fredy
Published: February 2024

In this contribution, we introduce a new practical approach to apply the fractional Fourier transform (FrFT) in the modeling of two optical systems: free space propagation (FSP) and a single lens processor (SLP). This formulation presents a simple way to stablish a direct relationship between physical parameters of the two optical systems and a real-valued fractional order. Furthermore, we employ and compare two numerical methods for evaluating the FrFT: the convolution and the Fresnel transform. Consequently, we apply this innovative approach to the digital decryption process in an opto-digital joint transform correlator cryptosystem, considering both the FSP and the SLP variants. We analyze both numerically and experimentally encrypted data to support our proposed method and to investigate the sensitivity of the decryption process with the fractional order. Notably, we obtain similar decryption results for both numerically and experimentally encrypted objects, demonstrating excellent agreement between the theoretical model, the numerical test, and the experiment.
Effect of water salinity on the focal tuning of an injected liquid lens used to modify the z-scan method
Authors: Shahsavand Yeganeh , Karimarji Safoura , Khorsandi Alireza
Published: February 2024

A water-injected liquid lens is fabricated to tune its focal length using the change in water salinity. It is found that when the salinity of water is changed from zero to 34.25%, the focal length can be changed by about 12.6 mm from 73.7 mm to 86.3 mm. A focal length resolution of approximately 0.75 × 10−2 mm and high temporal stability over a long period have been achieved for the lens foci. This lens is then used to modify the z-scan technique where the lens and the sample both remain fixed without displacement. The performance of the fabricated lens is evaluated by nonlinear refractive index measurement of a sample containing 10.82-pH-synthesized Silver nanoparticles suspended in water with 15 mM of concentration. For verification of the results, a nonlinear refractive index of (−10.6 ± 1.0) × 10−7 cm2 W−1 is firstly measured for the sample using a classical z-scan benefiting from a conventional focal-fixed lens. Interestingly, we found out that when the fabricated lens is replaced in the modified z-scan, the nonlinear refractive index of about (−8.1 ± 0.2) × 10−7 cm2 W−1 can be measured, indicating a similarity in the order and small difference in the coefficient compared to the classical z-scan. This outcome highlights the potential capability and simplicity of the fabricated lens in the modification of the classical z-scan technique.
Tribocorrosion studies on DLC films with silver nanoparticles for prosthesis applications
Authors: Radi P A , Vieira L , Leite P , Trava-Airoldi V J , Massi M , Reis D A P
Published: February 2024

Metals and their alloys are very important for orthopedic applications, and the basic requirements for a successful implant are chemical stability, mechanical behavior, and biocompatibility in body fluids and tissues. For prosthesis applications, the corrosion resistance of metals is one of the major prerequisites to avoid impairment of the material properties due to degradation. The combined action of corrosion and wear on the material is called tribocorrosion and DLC (Diamond-Like Carbon) films have been extensively studied to increase prosthesis biocompatibility and to protect from corrosion. Additionally, DLC coatings can prevent the prosthesis to release toxic elements due to plastic deformation and corrosion. This paper is about tribocorrosion studies on DLC and DLC-Ag (DLC containing silver nanoparticles) on Ti-6Al-4V substrates. These films were obtained by PECVD (Plasma Enhanced Chemical Vapor Deposition) using hexane as a precursor. The tribocorrosion behavior of uncoated and coated samples was investigated in the reciprocating mode in Ringer’s lactate solution. From the polarization test results, the protective efficiency of the film was calculated. Silver nanoparticles improved the corrosion resistance of the films. The protective efficiency was 15 and 19% for DLC and DLC-Ag films, respectively.
Differences in sediment nitrogen and phosphorus distribution between riverside and lakeside wetlands in a river-connected lake
Authors: Peng Zenghui , Niu Shiyu , Luo Qinghua , Li Youzhi
Published: February 2024

The distribution of nutrients in sediments is the result of multiple factors, including hydrological conditions and vegetation regulation, and in wetlands with complex hydrological conditions, this distribution is uncertain. In this study, the spatial distribution patterns of nitrogen and phosphorus in sediments were studied in the riverside and lakeside wetlands of Dongting Lake, a typical river-connected lake. The results showed that the nitrogen and phosphorus concentrations in the surface sediments were higher than those in the subsurface sediments in both the riverside and lakeside wetlands. In addition, the concentration of total nitrogen (TN) of lakeside wetlands in the surface sediments was higher than that of riverside wetlands, whereas the concentration of total phosphorus (TP) did not differ between the two wetland types. In the surface sediments, there were significant positive correlations between the TN and TP concentrations in the riverside wetlands (p < 0.05), but no significant correlation in the lakeside wetlands (p > 0.05). In riverside wetlands, the nitrogen and phosphorus concentrations showed strong spatial dependence. However, in the lakeside wetlands, the spatial dependence of NO3
−-N was strong, that of NH4
+-N was moderate, and that of TN and TP was weak. This study shows that both hydrology and vegetation cause differences in the distribution of nutrients in the sediments. The results obtained from this investigation clarify the differences of sediment nitrogen and phosphorus distributions in the two types of wetlands and provide a technical reference for the management of different wetland types.
Performance enhancement of cloud security with migration algorithm for choosing virtual machines in cloud computing
Authors: Manivannan R , Senthilkumar S , Kalaivani K , Prathap N
Published: February 2024

The management of the hardware as well as software resources entrusted to third-party service suppliers have shown to be extraordinarily remarkable and accessible with Cloud Computing (CC), a potential computing technology for the future. Yet, a major undertaking is characterized by security as well as the use of Virtual Machines (VMs) to perform a request. The main issue with using technology is security worries, which raises the need for a strong security system to safeguard data on the cloud. Thus, to address this problem, a method called Weighted Mean-based Radial Basis Function Network with Advanced Encryption Standard (WMRBFN-AES) is developed to improve cloud security along with the time of execution. Random keys are produced utilizing the Pseudo Random Number Generator (PRNG) technique, and the best keys are created employing the WMRBFN technique. In the WMRBFN technique, randomly generated keys are used as input, and the hidden layers yield an estimate associated with the secret key of the input. The output layer generates the most precise secret keys to encrypt the data. Encryption is carried out using the AES algorithm. The files about the encrypted data are kept in a cloud storage system. Reduced execution times for stakeholder demands (tasks) as well as optimal cloud resource utilization result from the selection of VMs, which significantly improves reliability. The Migration Algorithm (MA) is used in the cloud framework to optimize the selection of VMs to improve resource utilization and performance. The experimental findings of the suggested framework and the state-of-the-art frameworks are compared, and it was found that the new model performed better in terms of cost, resource utilization, service latency, throughput, and execution time.
Notes on noncommutative ergodic theorems
Authors: Litvinov Semyon
Published: February 2024

Given a semifinite von Neumann algebra

M

\mathcal M

equipped with a faithful normal semifinite trace

τ
\tau

, we prove that the spaces

L
0

(

M

,
τ
)

L^0(\mathcal M,\tau )

and

R

τ

\mathcal R_\tau

are complete with respect to pointwise—almost uniform and bilaterally almost uniform—convergences in

L
0

(

M

,
τ
)

L^0(\mathcal M,\tau )

. Then we show that the pointwise Cauchy property for a special class of nets of linear operators in the space

L
1

(

M

,
τ
)

L^1(\mathcal M,\tau )

can be extended to pointwise convergence of such nets in any fully symmetric space

E
⊂

R

τ

E\subset \mathcal R_\tau

, in particular, in any space

L
p

(

M

,
τ
)

L^p(\mathcal M,\tau )

,

1
≤
p
>
∞

1\leq p>\infty

. Some applications of these results in the noncommutative ergodic theory are discussed.
Geometry of spectral bounds of curves of unitary operators
Authors: Miglioli Martin
Published: February 2024

This article presents a new proof of a theorem concerning bounds of the spectrum of the product of unitary operators and a generalization for differentiable curves of this theorem. The proofs involve metric geometric arguments in the group of unitary operators and the sphere where these operators act.
Bounded Palais-Smale sequences with Morse type information for some constrained functionals
Authors: Borthwick Jack , Chang Xiaojun , Jeanjean Louis , Soave Nicola
Published: February 2024

In this paper, we study, for functionals having a minimax geometry on a constraint, the existence of bounded Palais-Smale sequences carrying Morse index type information.
A Crash Course on Incompressible Fluid Dynamics
Authors: Davidson P A
Published: February 2024

This chapter develops the key equations and fundamental concepts of incompressible fluid dynamics. It covers topics such as the Eulerian description of motion and the convective derivative, viscous shear stresses and Newton’s law of viscosity, Cauchy’s equation of Motion and the Navier–Stokes equation, boundary layers, viscous dissipation, vortex dynamics, and the Boussinesq approximation. The concepts are developed from first principles in a simple, accessible way. However, the reader is assumed to be fluent in the use of vector calculus and tensor analysis. References to further reading, both elementary and advanced, are provided for those readers who are relatively new to fluid mechanics.
Precession
Authors: Davidson P A
Published: February 2024

The earth’s mantle is subject to both free precession (the Chandler wobble) and forced precession (equinox precession), with the latter driving precessional motion in the fluid core of the earth. Following a brief introduction to rigid-body precession, both the Chandler wobble and equinox precession of the earth are discussed. The chapter concludes with Poincaré’s classical analysis of the precessional motion within the earth’s fluid core. The topic of fluid precession in planetary cores is a subtle one, but several suggestions for further reading are provided for the fearless reader intent on further study.
Instability II
Authors: Davidson P A
Published: February 2024

A rotating fluid heated from below becomes unstable when the temperature differences in the fluid are sufficiently large. This chapter starts with a review of the non-rotating case, i.e. of Rayleigh–Bénard convection in a thin fluid layer. This is followed by a detailed discussion of rotating Rayleigh–Bénard convection, where a critical distinction has to be made between the case where the instability is non-oscillatory and that where it is oscillatory. The chapter closes with a discussion of the thermal instability which occurs in a rotating annulus, often called the ‘Busse annulus’. This results in a form of thermally driven Rossby wave.
Vortex Breakdown
Authors: Davidson P A
Published: February 2024

A thin vortex tube can undergo a sudden expansion, often leading to instability and turbulence, if subject to an external deceleration. This is called vortex breakdown, and it is often observed in swirling flow in a slowly diverging pipe, and in the scroll vortices that develop on the upper surface of a delta wing. Simple model problems are presented for vortex breakdown, both in pipes and on delta wings. However, attempts to develop a generalized theory of vortex breakdown have proved to be problematic, as discussed towards the end of the chapter. Indeed, despite many analytical and experimental studies, the entire subject of vortex breakdown remains somewhat uncertain.
Tropical Cyclones
Authors: Davidson P A
Published: February 2024

Tropical cyclones are the largest, and most destructive, vortices that can form on the surface of the earth. This chapter reviews the conditions under which they form, as well as the observational evidence as to their structure. Real tropical cyclones are powered by evaporation from the warm tropical seas, but a simple cartoon of a ‘dry’ cyclone can reveal useful information about the fluid mechanics at work within a tropical cyclone. Despite their destructive power, and almost a century of scientific research, tropical cyclones are still poorly understood and remain a topic of intense debate.
Development and Validation of a Diagnostic Histopathological Scoring System for Capsular Contracture Based on 720 Breast Implant Capsules
Authors: Larsen Andreas , Timmermann Adam Mandrup , Kring Mikela , Mathisen Sif Birch , Bak Erik Eiler Frydshou , Weltz Tim Kongsmark , Ørholt Mathias , Vester-Glowinski Peter , Elberg Jens Jørgen , Trillingsgaard Jesper , Mielke Louise Vennegaard , Hölmich Lisbet Rosenkrantz , Damsgaard Tine Engberg , Roslind Anne , Herly Mikkel
Published: February 2024

Background

Capsular contracture is traditionally evaluated with the Baker classification, but this has notable limitations regarding reproducibility and objectivity.

Objectives

The aim of this study was to develop and validate procedure-specific histopathological scoring systems to assess capsular contracture severity.

Methods

Biopsies of breast implant capsules were used to develop histopathological scoring systems for patients following breast augmentation and breast reconstruction. Ten histological parameters were evaluated by multivariable logistic regression to identify those most associated with capsular contracture. Significant parameters (P < .05) were selected for the scoring systems and assigned weighted scores (1-10). Validation was assessed from the area under the curve (AUC) and the mean absolute error (MAE).

Results

A total of 720 biopsies from 542 patients were included. Four parameters were selected for the augmentation scoring system, namely, collagen layer thickness, fiber organization, inflammatory infiltration, and calcification, providing a combined maximum score of 26. The AUC and MAE for the augmentation scoring system were 81% and 0.8%, which is considered strong. Three parameters were selected for the reconstruction scoring system, namely, fiber organization, collagen layer cellularity, and inflammatory infiltration, providing a combined maximum score of 19. The AUC and MAE of the reconstruction scoring system were 72% and 7.1%, which is considered good.

Conclusions

The new histopathological scoring systems provide an objective, reproducible, and accurate assessment of capsular contracture severity. We propose these novel scoring systems as a valuable tool for confirming capsular contracture diagnosis in the clinical setting, for research, and for implant manufacturers and insurance providers in need of a confirmed capsular contracture diagnosis.

Level of Evidence: 3
The ontogeny of social networks in wild great tits (Parus major)
Authors: Wild Sonja , Alarcón-Nieto Gustavo , Aplin Lucy M
Published: February 2024

Sociality impacts many biological processes and can be tightly linked to an individual’s fitness. To maximize the advantages of group living, many social animals prefer to associate with individuals that provide the most benefits, such as kin, familiar individuals, or those of similar phenotypes. Such social strategies are not necessarily stable over time but can vary with changing selection pressures. In particular, young individuals transitioning to independence should continuously adjust their social behavior in light of developmental changes. However, social strategies exhibited during adolescence in animals are understudied, and the factors underlying social network formation during ontogeny remain elusive. Here, we tracked associations of wild great tits (Parus major) during the transition to independence and across their first year of life. Both spatial and social factors predicted dyadic associations. During the transition to independence in spring, fledglings initially preferred to associate with siblings and peers over non-parent adults. We found no evidence for preferred associations among juveniles of similar age or fledge weight during that time but weak evidence for some potential inheritance of the parental social network. By autumn, after juveniles had reached full independence, they exhibited social strategies similar to those of adults by establishing stable social ties based on familiarity that persisted through winter into the next spring. Overall, this research demonstrates dynamic changes in social networks during ontogeny in a species with a fast life history and limited parental care, which likely reflect changes in selective pressures. It further highlights the importance of long-term social bonds based on familiarity in this species.
Difference-based covariance matrix estimation in time series nonparametric regression with application to specification tests
Authors: Bai Lujia , Wu Weichi
Published: February 2024

Long-run covariance matrix estimation is the building block of time series inference. The corresponding difference-based estimator, which avoids detrending, has attracted considerable interest due to its robustness to both smooth and abrupt structural breaks and its competitive finite sample performance. However, existing methods mainly focus on estimators for the univariate process, while their direct and multivariate extensions for most linear models are asymptotically biased. We propose a novel difference-based and debiased long-run covariance matrix estimator for functional linear models with time-varying regression coefficients, allowing time series nonstationarity, long-range dependence, state heteroscedasticity and combinations thereof. We apply the new estimator to (i) the structural stability test, overcoming the notorious nonmonotonic power phenomena caused by piecewise smooth alternatives for regression coefficients, and (ii) the nonparametric residual-based tests for long memory, improving the performance via the residual-free formula of the proposed estimator. The effectiveness of the proposed method is justified theoretically and demonstrated by superior performance in simulation studies, while its usefulness is elaborated via real data analysis. Our method is implemented in the R package mlrv.