Direct Attack Research Articles

Muscle Changes during Direct Attack under Different Conditions in Elite Wheelchair Fencing.

The main objective of this study was to measure the speed and muscular participation of a direct attack gesture with and without fatigue in a sample of elite wheelchair fencers. The maximal isometric force, gestural speed, and resistance to gestural velocity were estimated in 10 elite performed direct fencers. The results revealed that sitting height and wingspan were important factors in achieving the highest speed, especially in women (r = 0.9; p = 0.07). Other factors, such as the elbow angle where the closed position was better, affected muscle contraction in both categories of athletes (p = 0.01). The onset of fatigue was earlier in category B than in category A, with greater variation in direct attack movement. The results highlight the importance of analyzing direct attacks for the best application of quick force, speed, and muscle participation, as well as identifying the onset of technical deterioration to devise a competitive strategy. These parameters may allow for precise design of conditioning sessions for elite wheelchair shooters.

Regiochemical Analysis of the ProTide Activation Mechanism.

ProTides are nucleotide analogues used for the treatment of specific viral infections. These compounds consist of a masked nucleotide that undergoes in vivo enzymatic and spontaneous chemical transformations to generate a free mononucleotide that is ultimately transformed to the pharmaceutically active triphosphorylated drug. The three FDA approved ProTides are composed of a phosphoramidate (P-N) core coupled with a nucleoside analogue, phenol, and an l-alanyl carboxylate ester. The previously proposed mechanism of activation postulates the existence of an unstable 5-membered mixed anhydride cyclic intermediate formed from the direct attack of the carboxylate group of the l-alanyl moiety with expulsion of phenol. The mixed anhydride cyclic intermediate is further postulated to undergo spontaneous hydrolysis to form a linear l-alanyl phosphoramidate product. In the proposed mechanism of activation, the 5-membered mixed anhydride intermediate has been detected previously using mass spectrometry, but the specific site of nucleophilic attack by water (P-O versus C-O) has not been determined. To further interrogate the mechanism for hydrolysis of the putative 5-membered cyclic intermediate formed during ProTide activation, the reaction was conducted in 18O-labeled water using a ProTide analogue that could be activated by carboxypeptidase Y. Mass spectrometry and 31P NMR spectroscopy were used to demonstrate that the hydrolysis of the mixed anhydride 5-membered intermediate occurs with exclusive attack at the phosphorus center.

How are teachers being attacked online? On cyberbullying and cyberaggression that targets school educators from the student’s perspective

The twin phenomena of cyberbullying and cyberaggression are among the most common e-threats. Today, much is known about the aggression and violence mediated by new media and targeted at students. However, there is still an empirical gap in the consideration of the mechanisms and forms of cyberaggression and cyberbullying targeting teachers. The aim of this study is to present 10 types of cyber-attacks that teachers have been subjected to in Poland in the last few years. The types of attacks presented include vilification in the information space (forums and social networking sites), direct attack using social networks, recording teachers without their consent, online blackmail, creation and dissemination of memes, photomontage, latent cyberbullying, destructive actions in the COVID-19 period, the creation of fake profiles, and the use of a digital tool in an offline environment. The subject of the study was the statements of post-secondary school graduates who had encountered such phenomena. The article highlights the need to increase digital safety for teachers.

Methodology for assessing the likelihood of completing a given task by an unmanned aerial vehicle

The article discusses a method for assessing the likelihood of a combat mission being accomplished by an un-manned aerial vehicle in conditions of countermeasure from attacked object. Countermeasures should be used when there is a threat of UAV intrusion into the territory of a protected facility or a direct attack on a guarded facility. The countermeasures process is divided into two main stages: detection (recognition, classification) of an attacking UAV and the effective countermeasure usage. When assessing the effectiveness of a countermeasures system, models are used: a UAV, a protected object, and the process of performing a combat mission by an unmanned aerial vehicle.

Synthesis of Diverse Allylic Sulfone Derivatives via Sequential Hydroalkoxylation of 1,3-Enynes.

A first metal-free protocol for the synthesis of allylic sulfones featuring aldehyde functionality at the δ-position has been reported. The formation of structurally complex δ,δ-dimethoxy allylic sulfones is enabled by the direct nucleophilic attack of methoxide onto the sulfone-containing 1,3-enynes. The present approach allows facile installation of acetal groups within the allylic sulfone scaffold, providing versatile platforms for further functionalization and drug development.

Nucleophiles Target the Tungsten Center Over Acetylene in Biomimetic Models.

Inspired by the first shell mechanism proposed for the tungstoenzyme acetylene hydratase, the electrophilic reactivity of tungsten-acetylene complexes [W(CO)(C2H2)(6-MePyS)2] (1) and [WO(C2H2)(6-MePyS)2] (2) was investigated. The biological nucleophile water/hydroxide and tert-butyl isocyanide were employed. Our findings consistently show that, regardless of the nucleophile used, both tungsten centers W(II) and W(IV), respectively, are the preferred targets over the coordinated acetylene. Treatment of 2 with aqueous NaOH led to protonation of coordinated acetylene to ethylene, pointing toward the Brønsted basic character of the coordinated alkyne instead of the anticipated electrophilic behavior. In cases involving isocyanides as nucleophiles, the attack on the W(II) center of 1 took place first, whereas the W(IV) complex 2 remained unchanged. These experiments indicate that the direct nucleophilic attack of W-coordinated acetylene by water, as some computational studies of acetylene hydratase propose, is unlikely to occur.

Direct contact and very rapid valgus distortion characterise the injury mechanism of anterior cruciate ligament ruptures in judo.

To analyse anterior cruciate ligament (ACL) rupture (ACLR) injury mechanisms in competitive judo using systematic video analysis, focusing on contact situations and biomechanics. Seventeen videos of judo competitions wherein athletes developed ACLRswere included and retrospectively evaluated by five analysts. In all videos, the momentof initial contact and the index frame were defined. The judo techniques leading to the injury; the occurrence of direct contact, indirect contactor noncontact mechanisms; the time interval between the initial contact and index frame; the positions of the hip, kneeand foot in relation to the initial contact and index frame; and the balance status during the initial contact and index frame were recorded. Eleven (65%) of ACLRs in judo involved direct contact. The mean time interval between initial contact and index frame was 15 ± 22 ms. Thirteen (77%) athletes were not balanced at initial contact. In the index frame, the hip was abducted in all cases and in combination with internal rotation in 12 (71%) cases. From initial contact to index frame, hip flexion increased in all cases; at index frame, the knee joint was internally rotated relative to the trunk in 12 (71%) cases, and the knee flexion angles increased from the initial contact. In the index frame, the foot was externally rotated relative to the knee in 12 (71%) cases, and severe valgus development of the knee with valgus collapse was observed in 14 (82%) cases. A direct attack on the knee was the most common injury mechanism observed. Valgus distortion appears to be the most important component of the mechanism of injury. With this knowledge, 'modified defence reactions'for specific judo techniques can be developed to reduce the injury risk. Level IV.

Ambush strategy enhances organisms’ performance in rock–paper–scissors games

We study a five-species cyclic system wherein individuals of one species strategically adapt their movements to enhance their performance in the spatial rock–paper–scissors game. Environmental cues enable the awareness of the presence of organisms targeted for elimination in the cyclic game. If the local density of target organisms is sufficiently high, individuals move towards concentrated areas for direct attack; otherwise, they employ an ambush tactic, maximising the chances of success by targeting regions likely to be dominated by opponents. Running stochastic simulations, we discover that the ambush strategy enhances the likelihood of individual success compared to direct attacks alone, leading to uneven spatial patterns characterised by spiral waves. We compute the autocorrelation function and measure how the ambush tactic unbalances the organisms’ spatial organisation by calculating the characteristic length scale of typical spatial domains of each species. We demonstrate that the threshold for local species density influences the ambush strategy’s effectiveness, while the neighbourhood perception range significantly impacts decision-making accuracy. The outcomes show that long-range perception improves performance by over 60%, although there is potential interference in decision-making under high attack triggers. Understanding how organisms’ adaptation their environment enhances their performance may be helpful not only for ecologists, but also for data scientists, aiming to improve artificial intelligence systems.

War and food insecurity in Ukraine

It is widely held that armed conflict is a central catalyst for food insecurity. However, existing studies tend to use aggregate measures of both conflict and food insecurity to analyze the long-term consequences of violence. We know far less about the immediate impacts of armed conflict on individual-level food insecurity. To address this gap, we collected two waves of probability surveys in Ukraine (Ns = 1081 and 811) at the start of the 2022 Russian invasion. We asked, specifically, whether Ukrainians’ exposure to military attacks was associated with the extent to which they reported food insecurity. The data indicate that one in three Ukrainians were food insecure at the time of the surveys. In turn, our analyses suggest that both direct attacks on the individual respondents, as well as indirect attacks (on their family members, acquaintances, and the municipalities in which they resided) relate to reported food insecurity. Notably, we found that the relationship between military attacks and food insecurity was only moderated by gender, but not age, education, or socioeconomic status. As the war in Ukraine continues, it is important to understand and document its consequences on civilians. Moreover, our findings likely have implications for policies tailoring wartime relief efforts – not only in Ukraine, but also in other countries experiencing large-scale military invasion.

Interactive attack-defense for generalized person re-identification

Generalized Person Re-Identification (GReID) aims to develop a model capable of robust generalization across unseen target domains, even with training on a limited set of observed domains. Recently, methods based on the Attack-Defense mechanism are emerging as a prevailing technology to this issue, which treats domain transformation as a type of attack and enhances the model’s generalization performance on the target domain by equipping it with a defense module. However, a significant limitation of most existing approaches is their inability to effectively model complex domain transformations, largely due to the separation of attack and defense components. To overcome this limitation, we introduce an innovative Interactive Attack-Defense (IAD) mechanism for GReID. The core of IAD is the interactive learning of two models: an attack model and a defense model. The attack model dynamically generates directional attack information responsive to the current state of the defense model, while the defense model is designed to derive generalizable representations by utilizing a variety of attack samples. The training approach involves a dual process: for the attack model, the aim is to increase the challenge for the defense model in countering the attack; conversely, for the defense model, the focus is on minimizing the effects instigated by the attack model. This interactive framework allows for mutual learning between attack and defense, creating a synergistic learning environment. Our diverse experiments across datasets confirm IAD’s effectiveness, consistently surpassing current state-of-the-art methods, and using MSMT17 as the target domain in different protocols resulted in a notable 13.4% improvement in GReID task average Rank-1 accuracy. Code is available at: https://github.com/lhf12278/IAD.

Undergraduate nursing students’ perception of bullying behavior and its relation to their academic achievement

Background Bullying among students is certainly not a new notion, however, due to its high incidence rates and the short-term and long-term implications. Students were subjected to a lot of factors during their study, either academic or clinical, that revealed them suffering high levels of depression, anxiety, and stress. Aim Assess undergraduate nursing students’ perception of bullying behavior and its relation to their academic achievement. Design A descriptive correlational research design was used. Sample A convenience sample (n=1255) of undergraduate nursing student out of N=3108. Setting The study was conducted in an accredited Faculty of Nursing which is affiliated to Cairo University. Tools Three tools were used personal characteristics data sheet, Bullying Behavior in Nursing Education Questionnaire, and academic achievement checklist Grade Point Average form. Results The main findings indicated that the bullying highest mean percent (58.33 and 55.14%) as perceived by the study sample was regarded as direct negative behaviors domains and attack on academic achievement domains, respectively. While the lowest mean percent (8.7%) was in regard to types of bullying domain. Data added that there was no statistically significant relationship (P=0.72) between the total perception of bullying in nursing education and students’ academic achievement. Conclusion The study concluded that there was no statistically significant relationship between total bullying as perceived by undergraduate nursing students in nursing education and their academic achievement. Recommendations Develop training programs to educate clinical instructors and assistant lecturers on how to achieve the academic objectives and advocate students’ rights. Design educational workshops to inform nursing students how to report bullying and how to overcome it.

Analyzing the Capacity of the Healthcare System in Gaza to Address Gaza Residents Needs

The present humanitarian crisis in Gaza has resulted in the devastation of medical facilities and health infrastructure. As of January 2024, the World Health Organization reports that 78% of primary care clinics funded by the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA, 2024) have ceased operations, and hospitals’ bed capacity throughout Gaza has decreased by more than 59% (World Health Organization, 2024). Direct military attacks on medical facilities as well as the blockade of medical supplies and humanitarian aid pose the largest obstacles to greater healthcare attainment in Gaza (IRC, 2024). Over the course of the conflict, there has been a surge in the number of people suffering from war injuries, which now totals 71,377 (Shurafa, 2024). The rise in the number of patients who require access to medical services in combination with the limited hospital functionality in the Gaza Strip is putting a massive strain on their already limited healthcare system; before the over 6 month long duration of direct military attacks by the Israeli Defence Forces (IDF) on hospitals in Gaza, data indicated a maximum ratio of 1.55 hospital beds per 1000 individuals across the entire region of the Gaza Strip, while the ratio in the US is around 2.35 hospital beds per 1000 individuals (Taylor, 2024). The already poor living conditions of the demographic–most of whom are housed in temporary structures in severe weather conditions with a lack of access to food and water for sustenance or hygiene–signify a need for a more robust healthcare system. However, triage conditions prioritize treatment of the most severe war injuries, which has forced hospitals to abandon previously established vaccination projects and disease surveillance programs, leaving the remaining population to suffer from preventable diseases such as chickenpox, upper respiratory infections, scabies, and Hepatitis A (Soni, 2024). Individuals who do receive medical care face higher levels of infection due to a lack of adequate sanitation, waste management measures, and basic hygiene supplies (The Economist, 2024).

Ring–Opening Mechanism of O‐heterocycles into α,ω‐Diols over Ni−La(OH)3: C−O Bond Hydrogenolysis of THFA to 1,5‐Pentanediol as a Case Study

AbstractThe elucidation of the ring–opening reaction mechanism is a critical step towards improving the catalytic performance for the conversion of biomass into value–added chemicals. Herein, we focused on the stepwise C−O bond hydrogenolysis mechanism of oxygen–containing heterocycles (O‐heterocycles) into α,ω‐diols, in particular THFA to 1,5‐PeD, over selective Ni−La(OH)3 in hydrogen–donor isopropanol. A mechanistic study was carried out on a structurally well–defined Ni−La(OH)3, where the mechanism was elucidated using a combination of kinetic and 13C NMR isotope labeling experiments. It was suggested that both Ni nanoparticles and La(OH)3 support play a critical role in the reaction mechanism, where basic hydroxide species of the support initially deprotonate the CH2OH and −OH modified furan, tetrahydrofuran and tetrahydropyran rings, adsorbing them chemically on the catalyst surface. This step is followed by a direct hydride attack on the second carbon atom of these rings, which is proposed to be the key step for ring cleavage, as indicated by the increased deuteration at this position. In addition to the direct hydrogenolysis using gaseous H2, it is assumed that a catalytic transfer hydrogenolysis reaction (CTH) reaction of THFA is proposed to proceed via the dehydrogenation of isopropanol over isolated Ni species, forming hydrogen species that can be adsorbed on the Ni surface or desorb as H2 molecules.

Howling shadows: First report of domestic dog attacks on globally threatened mountain tapirs in high Andean cloud forests of Colombia

Domestic dogs (Canis lupus familiaris) are recognised worldwide not only as man’s best friend, but also as a form of anthropogenic edge effect impacting wildlife through predation, competition and disease infection. In the Northern Andes, there is growing evidence of dogs inducing activity shifts or alterations in the habitat use of native mammalian species. However, little information exists on direct attacks of dogs on wildlife, even in the case of species of conservation concern such as the mountain tapir (Tapirus pinchaque). Here, we used camera traps to report two cases of dogs chasing and attacking mountain tapirs in a protected area of the Central Andes of Colombia. The first event showed a direct physical contact between a living adult mountain tapir and two dogs, but the picture’s angle did not lead to observable signs of wounds or other injuries. The second event showed an adult mountain tapir running while being chased by the same two dogs of the first event, denoting a stressful moment for the tapir. This may have negative consequences on the populations of mountain tapirs through decreased reproductive performance and foraging efficiency, increased potential for disease outbreaks and more. Population management and control of domestic dogs inside and around protected areas must be considered a priority in future conservation actions to support a healthy population of mountain tapirs and other imperilled species in the region.

Cyber dating abuse in university students from Spain and Latin America

The objective of the research was to study the presence of cyber violence against partners in university students in Spain and Latin America, as well as to analyze its relationship with romantic myths and ambivalent sexism. The research has a cross-sectional design. The sample was made up of 2,798 students from seven Spanish-speaking countries: Spain, El Salvador, Nicaragua, Colombia, Chile, Argentina, and Mexico. The results show few differences in means between men and women; However, the differences between countries are considerable, especially in the perpetration of direct attacks and control. The different forms of cyber violence against a partner tend to correlate, in a positive direction, with sexist attitudes and distorted beliefs about romantic love. In conclusion, prevention programs should take into account the new manifestations of violence that are appearing in virtual spaces.

Small RNAs direct attack and defense mechanisms in a quorum sensing phage and its host

Many, if not all, bacteria use quorum sensing (QS) to control collective behaviors, and more recently, QS has also been discovered in bacteriophages (phages). Phages can produce communication molecules of their own, or "listen in" on the host's communication processes, to switch between lytic and lysogenic modes of infection. Here, we study the interaction of Vibrio cholerae with the lysogenic phage VP882, which is activated by the QS molecule DPO. We discover that induction of VP882 results in the binding of phage transcripts to the major RNA chaperone Hfq, which in turn outcompetes and downregulates host-encoded small RNAs (sRNAs). VP882 itself also encodes Hfq-binding sRNAs, and we demonstrate that one of these sRNAs, named VpdS, promotes phage replication by regulating host and phage mRNA levels. We further show that host-encoded sRNAs can antagonize phage replication by downregulating phage mRNA expression and thus might be part of the host's phage defense arsenal.

When Your AI Becomes a Target: AI Security Incidents and Best Practices

In contrast to vast academic efforts to study AI security, few real-world reports of AI security incidents exist. Released incidents prevent a thorough investigation of the attackers' motives, as crucial information about the company and AI application is missing. As a consequence, it often remains unknown how to avoid incidents. We tackle this gap and combine previous reports with freshly collected incidents to a small database of 32 AI security incidents. We analyze the attackers' target and goal, influencing factors, causes, and mitigations. Many incidents stem from non-compliance with best practices in security and privacy-enhancing technologies. In the case of direct AI attacks, access control may provide some mitigation, but there is little scientific work on best practices. Our paper is thus a call for action to address these gaps.

Visible light photocatalytic performance of Co/Ag bimetallic coordination polymer catalysts designed from hard and soft acid-base theory

Heterometallic coordination polymers have promising applications in photocatalysis, and the design and selection of suitable organic ligands and coordination metals is the key to improve the catalytic activity of polymer photocatalysts. Herein, a novel Co/Ag bimetallic coordination photocatalyst, designed based on the hard and soft acid-base (HSAB) theory, has been successfully prepared by a stepwise method with Ag-S coordination as the main component and Co-N/Co-S as the complementary component. The obtained Co/Ag photocatalyst demonstrates excellent performance in the photocatalytic degradation (visible light) of halogenated phenolic pollutants. Degradation of 10 ppm of 4-chlorophenol could reach 100 % in 4 h, and 70 % degradation of 4-fluorophenol, which is even more difficult to degrade, could also be achieved. In addition, hydrogen production experiments conducted under visible light irradiation showed that the hydrogen production could reach 36.95 μmol h−1 g−1 for 6 h, which strongly demonstrated the excellent reduction ability of Co/Ag photocatalysts. The photocatalyst exhibits enhanced photocatalytic activity which is ascribed to the formation of Ag-S and Co-N/Co-S coordination, which greatly increases the charge density and facilitates charge transfer. Thus, the photogenerated electrons can induce both the conversion of O2 to •O2- for oxidation reactions, as well as the direct attack of the C-Cl bond for reduction reactions. This study demonstrates the successful design of the synergistic Co/Ag bimetallic coordination photocatalysts based on the HSAB theory, thereby offering a promising research avenue for the fabrication of heterometallic coordination photocatalysts.

IMPLEMENTASI PENGEMBANGAN SISTEM JARINGAN INTERNET PT. INKA MULTI SOLUSI SERVICE BERBASIS ROUTER MIKROTIK

The high usage of internet networks, coupled with various direct and indirect attacks, will affect the activities on the internet network. The office of PT. INKA Multi Solusi Service, located in Madiun City, has each employee working with their own computers, and the office's internet speed is 150 Mbps. However, the internet network at PT. INKA Multi Solusi Service faces several optimization issues. Three of these issues are related to internet security login, bandwidth conflicts, and unrestricted website access, leading to virus-related problems. The proposed solution involves implementing the Hierarchical Token Bucket (HTB) method, a bandwidth management technique used to control internet networks. HTB operates by allocating bandwidth hierarchically based on user needs. One of its advantages is that any unused bandwidth will be reallocated according to the priority needs of each user in a network. A captive portal will be implemented to protect the network from unauthorized users, ensuring that users have been granted permission to access the network through a username and password. Web filtering will safeguard internet users from harmful websites and restrict access to specific websites, especially those that could be potential sources of network viruses.

Biopterin metabolism and nitric oxide recoupling in cancer.

Tetrahydrobiopterin is a cofactor necessary for the activity of several enzymes, the most studied of which is nitric oxide synthase. The role of this cofactor-enzyme relationship in vascular biology is well established. Recently, tetrahydrobiopterin metabolism has received increasing attention in the field of cancer immunology and immunotherapy due to its involvement in the cytotoxic T cell response. Past research has demonstrated that when the availability of BH4 is low, as it is in chronic inflammatory conditions and tumors, electron transfer in the active site of nitric oxide synthase becomes uncoupled from the oxidation of arginine. This results in the production of radical species that are capable of a direct attack on tetrahydrobiopterin, further depleting its local availability. This feedforward loop may act like a molecular switch, reinforcing low tetrahydrobiopterin levels leading to altered NO signaling, restrained immune effector activity, and perpetual vascular inflammation within the tumor microenvironment. In this review, we discuss the evidence for this underappreciated mechanism in different aspects of tumor progression and therapeutic responses. Furthermore, we discuss the preclinical evidence supporting a clinical role for tetrahydrobiopterin supplementation to enhance immunotherapy and radiotherapy for solid tumors and the potential safety concerns.