Diffusion of small two-dimensional Cu islands on Cu(111) studied with a kinetic Monte Carlo method

Diffusion of small two-dimensional Cu islands (containing up to 10 atoms) on Cu(111) has been studied using the newly developed self-learning Kinetic Monte Carlo (SLKMC) method which is based on a database of diffusion processes and their energetics accumulated automatically during the implementation of the SLKMC code. Results obtained from simulations in which atoms hop from one fcc hollow site to another are compared with those obtained from a parallel set of simulations in which the database is supplemented by processes revealed in complementary molecular dynamics simulations at 500K. They include processes involving the hcp (stacking-fault) sites, which facilitate concerted motion of the islands (simultaneous motion of all atoms in the island). A significant difference in the scaling of the effective diffusion barriers with island size is observed in the two cases. In particular, the presence of concerted island motion leads to an almost linear increase in the effective diffusion barrier with size, while its absence accounts for strong size-dependent oscillations and anomalous behavior for trimers and heptamers. We also identify and discuss in detail the key microscopic processes responsible for the diffusion and examine the frequencies of their occurrence, as a function of island size and substrate temperature.Peer reviewe

Morphology of ledge patterns during step flow growth of metal surfaces vicinal to fcc(001)

The morphological development of step edge patterns in the presence of meandering instability during step flow growth is studied by simulations and numerical integration of a continuum model. It is demonstrated that the kink Ehrlich-Schwoebel barrier responsible for the instability leads to an invariant shape of the step profiles. The step morphologies change with increasing coverage from a somewhat triangular shape to a more flat, invariant steady state form. The average pattern shape extracted from the simulations is shown to be in good agreement with that obtained from numerical integration of the continuum theory.Comment: 4 pages, 4 figures, RevTeX 3, submitted to Phys. Rev.

PERBANDINGAN LEVERAGE RATIO SEBELUM DAN SESUDAH IPO PADA PERUSAHAAN YANG MELAKUKAN IPO PADA PERIODE 2013 – 2016

Penelitian ini menganalisa rasio leverage sebelum dan sesudah IPO serta mencari tahu seberapa besar perbedaan yang terjadi. Jenis penelitian ini adalah penelitian kuanitiatif. Penelitian ini menggunakan sampel laporan keuangan berupa aset dan utang perusahaan yang melakukan IPO pada periode 2013-2016 yang telah dipublikasikan, laporan keuagan tersebut digunakan untuk mengukur Debt to Asset Ratio (DAR) dan Debt to Equity Ratio (DER), dan Di samping itu, metode yang digunakan dalam penelitian ini adalah metode komparasi uji t sampel berpasangan. Hasil dari penelitian ini menunjukkan adanya penurunan pada Debt to Asset Ratio (DAR) dan Debt to Equity Ratio (DER

Pemanfaatan Taman Wisata Perairan (TWP) Gita Nada Lombok Barat Sebagai Laboratoroium Ekologi Alami

Penelitian ini bertujuan untuk mengetahui memperoleh hasil penelitian dari judul Pemanfaatan Taman Wisata Perairan (TWP) Gita Nada Lombok Barat Sebagai Laboratoroium Ekologi Alami. Manfaat dari penelitian ini adalah dapat mengimplikasikan hasil penelitian dari judul Pemanfaatan Taman Wisata Perairan (TWP) Gita Nada Lombok Barat Sebagai Laboratoroium Ekologi Alami dalam dunia pendidikan dan sumber pembelajaran laboratorium. Pendekatan pada penelitian ini adalah kombinasi kualitatif dan kuantitatif, untuk menjawab tujuan penelitian pertama dan kedua menggunakan pendekatan kuantitatif dan tujuan penelitian yang ketiga menggunakan pendekatan kualitatif. Penelitian akan dilakukan di Kawasan Konservasi Taman Wisata Perairan (TWP) Gili Tangkong, Gili Nanggu dan Gili Sudak (Gita Nada) yang berlokasi di Kecamatan Sekotong Kabupaten Lombok Barat, Provinsi NTB.  TWP Gita Nada merupakan salah satu dari 9 (sembilan) kawasan konservasi di Provinsi NTB yang telah ditetapkan melalui Keputusan Menteri Kelautan dan Perikanan Provinsi NTB. Berdasarkan kajian yang dilaksanakan oleh Pardede et al., (2013), kawasan perairan Lombok Barat memiliki keragaman generasi tertinggi kedua di Pulau Lombok setelah perairan Lombok Timur. Pada kawasan ini ditemukan 15 dari 17 famili karang kerang yang ada di Lombok. Karang keras paling banyak ditemukan merupakan famili Faviidae dan Pectinidae. Total jumlah genera yang ditemukan di Lombok Barat sebanyak 57 genera dari 66 genera yang ada di Pulau Lombok. Lokasi survei dengan jumlah genera terbanyak di Lombok Barat ditemukan di Gili Layar Timur dengan jumlah genera 4

On the role of personality in attitudes toward AI: Do AI’s freedom of choice and social proof matter?

Personal factors have been examined in recent literature for their impact on attitudes toward AI, often treating AI as a single, uniform concept and using samples from one cultural group. To address this, we differentiate between two modalities of AI operation: freedom of choice, referring to users’ ability or inability to choose alternatives to AI, and social proof, reflecting whether AI has been widely used and accepted by others. We also include samples from two distinct populations, Arab and UK. This study investigates the influence of the Big Five personality traits, Need for Cognition (NFC), and Locus of Control (LOC) on attitudes toward AI across four combinations of these modalities. A total of 639 participants (316 UK, 323 Arab) completed a survey containing scenarios, validated scales and bespoke, face-validated questions. Using hierarchical multivariate multiple regression (MMR), we analyzed how these personal factors predict two key dimensions of AI attitudes: acceptance (perceived personal and social benefits) and fear (ethical concerns and risks). Agreeableness consistently predicted more favorable attitudes across both cultures, while neuroticism was linked to greater fear. Internal LOC and higher NFC were associated with greater acceptance, highlighting the role of perceived control and cognitive engagement. Cultural differences emerged, with conscientiousness being more influential in the Arab sample and openness in the UK. Overall, personality traits had a weaker impact than expected, aligning with previous research treating AI as a single concept. The modality of operation showed limited effect. This study adds to AI acceptance literature by emphasizing psychological and cultural variability in public attitudes

An Adam based CNN and LSTM approach for sign language recognition in real time for deaf people

Hand gestures and sign language are crucial modes of communication for deaf individuals. Since most people can't understand sign language, it's hard for a mute and an average person to talk to each other. Because of technological progress, computer vision and deep learning can now be used to count. This paper shows two ways to use deep knowledge to recognize sign language. These methods help regular people understand sign language and improve their communication. Based on American sign language (ASL), two separate datasets have been constructed; the first has 26 signs, and the other contains three significant symbols with the crucial sequence of frames or videos for regular communication. This study looks at three different models: the improved ResNet-based convolutional neural network (CNN), the long short-term memory (LSTM), and the gated recurrent unit (GRU). The first dataset is used to fit and assess the CNN model. With the adaptive moment estimation (Adam) optimizer, CNN obtains an accuracy of 89.07%. In contrast, the second dataset is given to LSTM and GRU and a comparison has been conducted. LSTM does better than GRU in all classes. LSTM has a 94.3% accuracy, while GRU only manages 79.3%. Our preliminary models' real-time performance is also highlighted

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Osasairausvapaa sairausloman vaihtoehtona tuki- ja liikuntaelinten sairauksissa

Tutkimushankkeen tarkoituksena oli selvittää, voidaanko jo työkyvyn heikkenemisen alkuvaiheessa lyhennetyllä työpäivällä sairausloman aikana eli ns. osasairausvapaalla edistää työhön paluuta ja vähentää tuki- ja liikuntaelinten kipuja sekä niistä aiheutuvaa haittaa tavanomaiseen sairauspoissaoloon verrattuna

Parameter estimation of photovoltaic models based on improvement of moutain gazelle optimizer algorithm

IntroductionThe mountain gazelle (Gazella gazella) is a native species to the Middle East and has experienced a notable population decline due to human-induced habitat loss and fragmentation. In Saudi Arabia, the current status and distribution of this species remain poorly understood, necessitating data-driven conservation assessments.Methods, Results, and DiscussionThis study combined recent occurrence records with remote sensing and GIS-based environmental variables to model suitable habitats for the mountain gazelle using the MaxEnt algorithm. Key predictors included vegetation indices, land cover types, and elevation. The results identified core habitat areas in the western and southwestern regions, some of which fall outside current protected zones. These findings underscore the importance of expanding conservation areas and demonstrate how spatial modeling supports effective wildlife management in arid environments