Knowledge Graphs have demonstrated a real advantage in knowledge representation, leveraging graphs NoSQL structures and schema-less technology, which offers superior comprehension, knowledge ...representation, interpretation, and reasoning. The problem is that current methods for Knowledge Graph embedding rely on the topology of the graph, and essential information about entities and relations has not been fully employed, failing to utilize the graph’s ontology to limit the spurious growth of edges, leading to inaccurate, misleading, and fabricated knowledge. This research aims to establish a method to restrict the spurious growth of host graph by imposing an upper bound on edge embedding using the claim’s and the host’s ontology graph. Through this research, a claim-ontology signature artifact was designed to facilitate open-environment KG completion. This artifact establishes the upper bound for the type of edges predicted by the link prediction algorithm, thus preventing the spurious growth of edges within the Knowledge Graph. Furthermore, the artifact was evaluated in the context of three use cases: host-guided embedding, claim-guided embedding, and topic-guided embedding, using a quantitative framework for design science evaluation. The main finding is that the spurious growth of edges can be limited by imposing an upper bound on the possible edge embedding using the claim’s graph and the host ontology graph. A secondary finding is that the artifact could serve as an instrument to manage the ontology-topology tradeoff in Knowledge Graphs.
Angiogenesis and neurogenesis play irreplaceable roles in bone repair. Although biomaterial implantation that mimics native skeletal tissue is extensively studied, the nerve-vascular network ...reconstruction is neglected in the design of biomaterials. Our goal here is to establish a periosteum-simulating bilayer hydrogel and explore the efficiency of bone repair via enhancement of angiogenesis and neurogenesis. In this contribution, we designed a bilayer hydrogel platform incorporated with magnesium-ion-modified black phosphorus (BP) nanosheets for promoting neuro-vascularized bone regeneration. Specifically, we incorporated magnesium-ion-modified black phosphorus (BP@Mg) nanosheets into gelatin methacryloyl (GelMA) hydrogel to prepare the upper hydrogel, whereas the bottom hydrogel was designed as a double-network hydrogel system, consisting of two interpenetrating polymer networks composed of GelMA, PEGDA, and β-TCP nanocrystals. The magnesium ion modification process was developed to enhance BP nanosheet stability and provide a sustained release platform for bioactive ions. Our results demonstrated that the upper layer of hydrogel provided a bionic periosteal structure, which significantly facilitated angiogenesis via induction of endothelial cell migration and presented multiple advantages for the upregulation of nerve-related protein expression in neural stem cells (NSCs). Moreover, the bottom layer of the hydrogel significantly promoted bone marrow mesenchymal stem cells (BMSCs) activity and osteogenic differentiation. We next employed the bilayer hydrogel structure to correct rat skull defects. Based on our radiological and histological examinations, the bilayer hydrogel scaffolds markedly enhanced early vascularization and neurogenesis, which prompted eventual bone regeneration and remodeling. Our current strategy paves way for designing nerve-vascular network biomaterials for bone regeneration.
A schematic diagram of the bilayer hydrogel scaffold for vascularization, neurogenesis, and bone regeneration. The upper (GelMA-BP@Mg) hydrogel served as a periosteal repair layer, while the bottom layer (GelMA-PEG/β-TCP) hydrogel served as a bone repair layer. Together, they accelerated the formation of a periosteal nerve-vascular network that enhanced bone regeneration. Display omitted
•Developing a periosteum-simulating bilayer hydrogel to improve the efficiency of neuro-vascularized bone repair.•A magnesium-ion-modified black phosphorus (BP) nanosheets incorporated hydrogel platform was designed.•Designing nerve-vascular network biomaterials for bone regeneration.
The accuracy and diversity of recommendation algorithms have always been the research hotspot of recommender systems. A good recommender system should not only have high accuracy and diversity, but ...also have adequate robustness against spammer attacks. However, the issue of recommendation robustness has received relatively little attention in the literature. In this paper, we systematically study the influences of different spammer behaviors on the recommendation results in various recommendation algorithms. We further propose an improved algorithm by incorporating the inner-similarity of user's purchased items in the classic KNN approach. The new algorithm effectively enhances the robustness against spammer attacks and thus outperforms traditional algorithms in recommendation accuracy and diversity when spammers exist in the online commercial systems.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We aimed to compare the intraoperative and early postoperative clinical outcomes of using an acromioclavicular joint hook plate (AJHP) versus a locking plate (LP) in the treatment of anterior ...sternoclavicular joint dislocation.
Seventeen patients with anterior sternoclavicular joint dislocation were retrospectively analyzed from May 2014 to September 2019. Six patients were surgically treated with an AJHP, and 11 were surgically treated with an LP. Five male and one female patients composed the AJHP group, and nine male and two female patients composed the LP group. The mean age of all patients was 49.5 years.
Reduction and fixation were performed with AJHP or LP in all 17 patients. The mean operative blood loss, operative time, and length of incision in the AJHP group were significantly better than those in the LP group. Shoulder girdle movement of the AJHP group was significantly better than that of the LP group.
This study revealed that AJHP facilitated glenohumeral joint motion, reduced the risk of rupture of mediastinal structures, required a shorter incision, and had lesser blood loss and a shorter duration of operation compared with LP. However, some deficiencies require further improvement.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Online education has become increasingly popular in recent years, particularly in the field of engineering. However, one of the challenges of online engineering education is providing students with ...hands-on laboratory experiences that require being at an on-campus laboratory. Virtual laboratory technical solutions have been developed during the last decade to allow learners to simulate engineering systems online or to connect to predesigned systems modules within physical laboratories. However, these predesigned solutions need to be acquired as software and hardware components which would require a certain budget and a training time before they can be used. In addition, these solutions do not concentrate on the construction portion of the systems under experimentation, but rather on testing the predesigned module using a virtual application that connects to it. In this paper we have developed a solution that would enable online learners to build virtual systems step by step at their ends and connect them to real time on-campus labs to perform remote experimentation. We have designed and developed a prototype for a simple, easy to learn and use virtual laboratory model for logic gates systems.. We have used a combination of technologies such as Virtual Networking Computing (VNC) technology, Video Conferencing (VC) technology, and Object-Oriented programming (OOP). Our solution was practically proven using Python programming running on a raspberry PI system to construct sample examples virtual logic gates applications. This allows online students to concentrate on constructing, step by step, logic gates systems virtually, and to control actual physical logic gates systems within an on-campus lab with the help of a webcam. Our solution was tested by group of learners and was proved to be a cost-effective alternative to traditional laboratory experiences, as our virtual laboratory can be accessed from anywhere with an internet connection, eliminating the need for additional expensive equipment and laboratory space.
The surgical treatment of acetabular fracture has adverse outcomes and high risk, and minimally invasive method is a good way to reduce complications and improve hip joint function. This study is to ...investigate the treatment of certain acetabular fractures primarily involving the anterior column and quadrilateral plate using a limited pararectus approach and the anatomical plates.
A consecutive cohort of 17 patients with anterior displaced acetabular fractures were managed operatively with a limited approach and the anatomical plates. Ten patients had anterior column fractures, 1 patient had anterior wall fracture, 4 patients had transverse fractures and 2 patients had anterior column with posterior hemi-transverse fractures. The inferior half of the pararectus approach was adopted to open the medial window and to access the anterior column and the quadrilateral plate. The anatomical plates were used for internal fixation. Residual displacements were assessed on the postoperative CT scans using a standardized digital method. The surgical details, hip functional outcomes, and complications were noted.
All of the patients were operated using the limited pararectus approach and the anatomical plates successfully. The mean operative time and blood loss were 90.9 min and 334.1 ml, respectively. The average postoperative residual gap and step displacement on CT were 2.9 mm and 0.7 mm, respectively. The radiological outcome was estimated according to the Matta score, ten of the cases were graded anatomical, six were graded imperfect, and one was graded poor. Follow up averaged 15 months. Functional outcomes were excellent for nine, good for six, and fair for two. It was noted that one case of peritoneal injury was repaired intraoperatively.
The limited pararectus approach with the advantages of less trauma, direct exposure to the anterior column and quadrilateral plate. The anatomical plates can fit with the surface of the acetabulum, which saves the time of remodeling plates during operation and facilitate fracture reduction. The combination approach can be a good choice for limited surgery of displaced anterior acetabular fractures especially involving the quadrilateral plate.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The skeleton is a highly innervated organ in which nerve fibers interact with various skeletal cells. Peripheral nerve endings release neurogenic factors and sense skeletal signals, which mediate ...bone metabolism and skeletal pain. In recent years, bone tissue engineering has increasingly focused on the effects of the nervous system on bone regeneration. Simultaneous regeneration of bone and nerves through the use of materials or by the enhancement of endogenous neurogenic repair signals has been proven to promote functional bone regeneration. Additionally, emerging information on the mechanisms of skeletal interoception and the central nervous system regulation of bone homeostasis provide an opportunity for advancing biomaterials. However, comprehensive reviews of this topic are lacking. Therefore, this review provides an overview of the relationship between nerves and bone regeneration, focusing on tissue engineering applications. We discuss novel regulatory mechanisms and explore innovative approaches based on nerve-bone interactions for bone regeneration. Finally, the challenges and future prospects of this field are briefly discussed.
Objectives
In geriatric acetabular fractures, the quadrilateral surface (QLS) was frequently involved in acetabular fracture patterns and accompanied by medial displacement. It was important to ...buttress the medial displaced QLS and reconstruct the congruity of the affected acetabulum. To evaluate the clinical effectiveness of the novel infra‐pectineal quadrilateral surface buttress plates for the treatment of geriatric acetabular fractures.
Methods
Twenty‐three geriatric patients who were treated for acetabular fractures involving QLS with the novel infra‐pectineal buttress plates (NIBP) through a single supra‐ilioinguinal approach between January 2015 and June 2019 were retrospectively analyzed; all patients received at least 1 year's follow‐up. All patients were aged ≥60 years old and including 18 males and five females. Radiologic and clinical outcomes of patients involved in the study were collated and analyzed according to the Matta scoring system and the Merle D'Aubigné–Postel scoring system. The functional recovery scoring was compared using q‐test.
Results
All 23 consecutive patients had relatively satisfactory clinical treatment effectiveness. Average ages, length of incision, operation time, and intraoperative blood loss were 69.8 ± 6.1 years, 12.1 ± 2.6 cm, 166.5 ± 43.5 min, and 500 (500,700) ml, respectively. According to the Matta scoring system, 14 cases of reduction were graded as excellent, five as good, and four as fair. At the last follow‐up, the clinical outcome evaluation was excellent in 13 cases, good in seven cases, and poor in three cases with the use of the Merle D'Aubigné–Postel scoring system. The difference of modified Merle D'Aubigne‐Postel score at 3 months, 6 months and last follow up was statistically significant (F = 21.56, p < 0.05). Postoperative lateral femoral cutaneous nerve injury occurred in three patients and heterotopic ossification occurred in one patient.
Conclusions
For the treatment of geriatric acetabular fractures, the NIBP could provide stable and effective fixation to the QLS involved acetabular fractures, and related satisfactory clinical results with few complications were noted.
In geriatric acetabular fractures, the quadrilateral surface is often involved in the fracture pattern and medially displaced. We used our modified anterior approach and special infra‐pectineal plate to realized direct view and buttress, respectively, for management of quadrilateral surface.
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