1,721,547 research outputs found
The long-run reversal in the long run: Insights from two centuries of international equity returns
No full textWe perform the most comprehensive test of long-term reversal in national equity indices ever done. Having examined data from 71 countries for the years 1830 through 2019, we demonstrate a strong reversal pattern: the past long-term return negatively predicts future performance. The phenomenon is not subsumed by other established cross-sectional return patterns, including the value effect. The long-term reversal is robust to many considerations but highly unstable through time. Finally, our findings support the overreaction explanation of this anomaly.</p
Prevalence of gastrointestinal helminths in pastoral sheep and goat flocks in the Cholistan desert of Pakistan
No full textSmall ruminants are a major source of cash for many rural populations, especially in semi-arid and arid regions of developing countries. Extensively managed animals often host gastrointestinal parasites, and even chronic infestations lead to economic losses. We evaluated the prevalence of gastrointestinal helminths in sheep and goats of the Cholistan desert, Pakistan, where livestock is the backbone of the regional economy. Fresh faeces (10 - 15 g) were collected from 500 sheep and 500 goats across five different localities. Standard parasitological techniques served to identify parasite eggs, and copro-culture enabled larval determination of specific nematodes. Overall helminth prevalence was 78.1% across the 1000 animals; pure nematode infestations were most prevalent (37.5%), followed by pure trematode (7.9%), pure cestode (2.6%) and pure protozoa infestations (0.8%). Mixed infestations with nematodes and trematodes occurred in 6.4% of all animals, mixed nematode-cestode infestations in 3.8%, and all three groups were found in 19.1% of the sheep and goats. In goats more males (81.1%) than females (77.0%) were infested, the opposite was found in sheep (73.6% males, 79.5% females). Parasites were especially prevalent in suckling goats (85.2%) and sheep (88.5%) and to a lesser extent in young (goats 80.6%, sheep 79.3%) and adult animals (goats 72.8%, sheep 73.8%). Given the high infestation rates, particular attention should be paid to management of suckling animals. A general means of reducing infestation rates might be the systematic testing of traditional plant-based remedies against helminths for cheap and regular deworming of the herds
In vitro efficacy of selected medicinal plants from Cholistan desert, Pakistan, against gastrointestinal helminths of sheep and goats
No full textIn vitro efficacy of selected medicinal plants from Cholistan desert, Pakistan, against gastrointestinal helminths of sheep and goats
No full textPrevalence of gastrointestinal helminths in pastoral sheep and goat flocks in the Cholistan desert of Pakistan
No full textSmall ruminants are a major source of cash for many rural populations, especially in semi-arid and arid regions of developing countries. Extensively managed animals often host gastrointestinal parasites, and even chronic infestations lead to economic losses. We evaluated the prevalence of gastrointestinal helminths in sheep and goats of the Cholistan desert, Pakistan, where livestock is the backbone of the regional economy. Fresh faeces (10 - 15 g) were collected from 500 sheep and 500 goats across five different localities. Standard parasitological techniques served to identify parasite eggs, and copro-culture enabled larval determination of specific nematodes. Overall helminth prevalence was 78.1% across the 1000 animals; pure nematode infestations were most prevalent (37.5%), followed by pure trematode (7.9%), pure cestode (2.6%) and pure protozoa infestations (0.8%). Mixed infestations with nematodes and trematodes occurred in 6.4% of all animals, mixed nematode-cestode infestations in 3.8%, and all three groups were found in 19.1% of the sheep and goats. In goats more males (81.1%) than females (77.0%) were infested, the opposite was found in sheep (73.6% males, 79.5% females). Parasites were especially prevalent in suckling goats (85.2%) and sheep (88.5%) and to a lesser extent in young (goats 80.6%, sheep 79.3%) and adult animals (goats 72.8%, sheep 73.8%). Given the high infestation rates, particular attention should be paid to management of suckling animals. A general means of reducing infestation rates might be the systematic testing of traditional plant-based remedies against helminths for cheap and regular deworming of the herds
Elucidation of the external electric field effect on the translocation of R-derivatives peptides across a symmetric lipid bilayer using the umbrella sampling method.
No full textKeywords: Electroporation; constant electric field; oligoarginine; umbrella sampling (US); steered molecular dynamics (SMD); Colvars-SMD; Constraint-SMD; potential of mean force (PMF); octa-arginine.The translocation of cargoes like nanoparticles (NP) and macromolecules like DNA and RNA across the model membrane through different cell-penetrating peptides (CPPs) has been the point of research for the last few years. Electroporation is a technique that helps in transferring foreign molecules like proteins, drugs, antibodies, and highly charged molecules such as DNA into the cell membrane. However, how the external electric field helps in increasing the membrane permeability has yet to be elucidated in detail. Therefore, in this MD study, the presence and the absence of a constant electric field effect were studied during the individual interaction of oligoarginine peptides (R4, R8) with the symmetric lipid bilayer having the following lipid composition: DOPC/DOPG (4:1). The umbrella sampling (US) technique was implemented to compute the free energy barriers. To generate initial basis values for umbrella bins, two steered molecular dynamics (SMD) approaches were used in this study: Colvars-SMD and Constraint- SMD. The results showed that no considerable difference in the potential of mean force (PMF) for both peptides (R4/R8) is present for the former method. However, initially, there was not a significant free energy barrier difference for tetra-arginine with and without an electric field for the later method, but at the end of the simulation, it started showing a noticeable difference with a higher PMF value without an electric field and lower PMF value for with electric field. Furthermore, the octa-arginine case also exhibited similar behavior to the R4 peptide; the free energy barrier was higher in the absence of an electric field and lower in the presence of an electric field. These outcomes are consistent with the already reported literature that the applied electric field lowers the free energy cost. It appears that the higher interaction energy between CPP-lipids may mainly account for the higher free energy barrier for the R8 peptide than the R4 peptide. This research provides an atomic-level insight into how the external electric field affects the translocation of R-derivative peptides through the symmetric membrane. Keywords: Electroporation, constant electric field, oligoarginine, umbrella sampling (US), steered molecular dynamics (SMD), Colvars-SMD, Constraint-SMD, potential of mean force (PMF), octa-arginine.|현재 연구의 주요 초점은 세포막을 통한 CPP의 전위 동안 외부 전위의 영향을 밝히는 것이었습니다. 따라서 외부 전위 효과를 연구하기 위해 구현하기 쉽고 전 세계적으로 허용되는 일정한 전기장 접근 방식이 채택되었습니다. 실제 세포의 일반적인 전위를 모방하기 위해 적용된 전위는 생리학적 범위(0.05V/nm)로 유지됩니다. 또한, 실제 세포 매개변수를 복제하기 위해 우리가 이미 알고 있는 것처럼 지질 혼합물(DOPC/DOPG: 4/1)이 사용되었습니다. 포유류 세포에는 두 가지 유형 이상의 지질이 존재합니다. 현재 시뮬레이션 결과는 적용된 전위가 펩타이드(CPP)가 세포막을 통과하는 데 도움이 된다는 이미 보고된 실험 및 시뮬레이션 결과와 일치합니다. 얻은 결과는 인가된 전기장이 양전하를 띤 CPP를 내부 전단지 쪽으로 밀어내고 결과적으로 기공이 생성되면 전위를 위한 자유 에너지 비용이 낮아진다는 원자 수준의 그림을 제공합니다. 기공이 없는 경우 자유 에너지 장벽에 대한 눈에 띄는 외부 전위 효과는 관찰되지 않았습니다. Colvars SMD 케이스를 볼 수 있습니다. 따라서 이러한 결과는 수공이 전기장 추진 효과를 관찰하는 데 매우 중요한 부분임을 전달합니다. 이 외에도 가능한 많은 요인 중에서 CPP-지질 사이의 정전기 에너지가 주로 R4 시스템보다 R8 시스템의 더 높은 자유 에너지 장벽을 담당할 수 있음을 관찰했습니다. 물론, 우리는 이 엔탈피 매개변수만으로는 힘 수단의 잠재력 차이를 단독으로 설명하기에 충분하지 않다는 사실을 인정합니다. 그러나 우리는 음전하 지질(DOPG)로 인해 CPP-지질 간의 상호 작용 에너지가 자유 에너지 차이를 비교하는 데 매우 중요한 요소라고 믿습니다. 전반적으로, 현재 연구는 세포막을 통한 펩타이드 전위 동안 외부 전기장이 어떻게 자유 에너지 비용을 낮추는지에 대한 나노 수준의 통찰력을 제공합니다. 우리는 이 연구가 생리학적 범위의 적용된 외부 잠재력이 어떻게 펩타이드 내재화를 돕는지에 대한 향후 연구에 대한 기본 아이디어를 제공할 것이라고 믿습니다.
우리는 여전히 많은 질문과 매개변수에 대해 답변하고 고려해야 한다는 점을 인정합니다. 예를 들어, 전하를 띤 측쇄를 고려하면 pH 효과는 어떻게 되는지, 적용된 전위를 높이거나 낮추면 PMF 값이 얼마나 변하는지, 현재 펩타이드의 임계 농도(4 또는 6)를 사용하면 어떤 일이 일어날지 등을 알 수 있습니다. 지질 이중층, 현재 시스템에 원통형 반응 좌표나 1차원 이상의 반응 좌표와 같은 다른 반응 좌표를 사용하면 어떤 영향이 발생합니까?
따라서 향후 프로젝트에는 다음 작업이 포함됩니다.
1) 다양한 외부 전위 값을 사용하여 현재 시뮬레이션 시스템에 미치는 영향을 비교합니다.
2) 펩타이드의 역치 농도를 이용하여 협력 효과를 연구합니다.
3) 원통형 RC와 같은 다양한 반응 좌표를 구현하여 자유 에너지 장벽에 미치는 영향을 연구합니다.I. Introduction ………………………………………………………………………………………………1
1.1 Research Aims ……………………………………………………………………………………2
II. Methodology ……………………………………………………………………………………………..3
2.1 Initial Peptides Topologies and Coordinates ……………………………………………………...3
2.2 Initial Lipid Bilayer Composition ………………………………………………………………...4
2.3 Merge Topology Preparation ……………………………………………………………………...5
III. Simulation Study Details ………………………………………………………………………………….7
3.1 Minimization ………………………………………………………………………………………8
3.2 Equilibration ……………………………………………………………………………………….8
3.3 Force Field …………………………………………………………………………………………9
3.4 External Electric Field …………………………………………………………………………….10
IV. Simulations Methods ……………………………………………………………………………………..11
4.1 Steered Molecular Dynamics (SMD) ……………………………………………………………..12
4.1.1 Constraint-steered molecular dynamics (SMD) ………………………………………….......12
4.1.2 Colvars-steered molecular dynamics (SMD) ………………………………………………....12
4.1.3 Parameters Used for Constraint SMD ………………………………………………………...13
4.1.4 Colvars Module Used for SMD …………………………………………………………........14
4.2 Umbrella Sampling Method (US) ……………………………………………………………........16
V. Results and Discussion ……………………………………………………………………………….........19
5.1 R4-R8 Constraint-SMD method for PMF calculation with & without Electric-field ……………..19
5.2 R4-R8 Colvars-SMD method for PMF calculation with & without Electric-field…………….…..23
5.3 R4-R8 Constraint-Colvars-SMD methods’ PMFs convergence check…………………………….26
5.4 R4-R8 Constraint-Colvars-SMD methods’ PMFs vs. Electrostatic Energy b/w CPP-Lipids……...29
VI. Conclusion and Future Direction…………………………………………………………………………..33
VII. References………………………………………………………………………………………………… 33MasterdCollectio
Application of friction stir spot welding on additive manufactured carbon fiber composite
No full textFriction stir spot welding as a solid state processing technique is used to join dissimilar and similar metals, composites and polymers. This study illustrates the implementation of friction stir spot welding (FSSW) on additive manufactured nylon-based composites with chopped carbon fibre reinforcements. The purpose of this study is to employ FSSW technique for joining additive manufactured carbon fibre composites. The utilization of pinless tool serves a crucial function in the formation of sound welded joints. The joining process consists of two mechanisms: the piercing and melting of the sheets and the adhesive bonding during the re-solidification. As a result of the FSSW process, the joints indicate a decent mechanical performance with a lap shear failure force (LSFF) of about 250N.Ozyegin Universit
EatSense
No full textWe introduce a new benchmark dataset named EatSense that targets both computer vision and the healthcare community. EatSense is recorded while a person eats in a dining room uncontrolled setting. Key features are: First, it introduces challenging atomic actions for recognition. Second, the hugely varying lengths of actions in EatSense, make it nearly impossible for current temporal action localization frameworks to localize them. Third, it provides the capability to model complete eating behaviour (chain of action-based). Lastly, it simulates minor changes in motion/performance. Moreover, we conduct extensive experiments on EatSense with baseline deep learning-based approaches for bench-marking and hand-crafted feature-based approaches for explainable applications. We believe this dataset will benefit future researchers in building robust temporal action localization networks, behaviour recognition and performance assessment models for eating. The dataset is related to the publication by Muhammad Ahmed Raza, Longfei Chen, Nanbo Li and Robert B. Fisher (2023). "EatSense: Human centric, action recognition and localization dataset for understanding eating behaviors and quality of motion assessment", Image and Vision Computing, 137, 104762, ISSN 0262-8856, https://doi.org/10.1016/j.imavis.2023.10476
The externality cost of environmental (dis)amenities in the urban housing market: an emerging evidence from Pakistan
No full textRising urbanization on abiotic environmental conditions in housing units is one of the most severe difficulties that city municipality authorities face, all over the world. Waste production has increased as a result of households failing to implement waste management strategies that ensure sustainability. Thus, property values in the housing market have regularly deteriorated as a result of environmental (dis)amenities. The study examines the impact of a waste dump site on proximate property values in Pakistan’s twin cities. Using a systematic random sampling technique, questionnaires were distributed to 849 households. 35 dump sites were chosen from 100 metres to 500 metres. The dump sites were chosen based on their size and proximity to residential homes in the study area. The empirical results show that the distance between a residential property and a waste dump site significantly impacts rental values. Moreover, rents exhibit a negative relationship with increasing distance from the dump sites. Based on applied findings, more proactive enforcement of sanitary laws and regulations, such as removing all irregular dump sites from residential areas, is recommended
Simulation based topology optimization assessment with manufacturing constraints
Full text linkIn Automotive and Aerospace industries, Topology Optimization (TO) is being used for the last few decades to produce lightweight structures. On the other hand, TO produces very complex geometrical features (i.e. irregular shape and hidden cavities along the thickness) that is sometimes difficult to be manufactured even with Additive Manufacturing (AM) and Casting techniques. In this paper suitable design and manufacturing constraint (MC) are applied during TO process that act as an Optimization Tool (OT) and improves geometrical features of the mechanical structures for easy manufacturing. Three mechanical structures with different geometries and boundary conditions have been considered for analysis purpose. Topology Optimization based on linear static analysis has been performed using OptiStruct (HyperWorks) solver. Finally, results of analysis conclude that the proposed OT produces lightweight structures with very simple geometries that can easily be manufactured with the help of AM or Casting techniques
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