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The present review paper examines the use of different types of polymeric matrix composites in hard tissue replacement applications. The review presents the actual state of the art in the fields of bioinert composites for permanent applications, biodegradable matrix composites for temporary applications and the emerging area of injectable composites. In all cases some recent developments are also discussed. The paper starts with an introduction to locate the reader. Bone–analogue composites are then extensively discussed. Several other systems based on an inert polymeric matrix are described, focusing on their proposed applications. A great emphasis is afterwards given to biodegradable matrix systems. The most widely used synthetic bioresorbable systems are analysed and compared with an example of natural origin degradable composites–starch based composites. Finally, composite systems that are non-processable by melt based routes and in many cases injectable are discussed in detail, including several recent developments on this emerging area of research. [Copyright &y& Elsevier]

Bone and joint infections can present in many ways. It is important to understand the features of the infection which contribute to the complexity of the condition and affect the outcome of treatment for the patient. Classification systems can do this but are often ignored in clinical decision-making and design of research projects. Recent work has better documented the key features of the patient and limb which must be considered when treatment is planned. This paper reviews the available classifications and their application to clinical practice. The Cierny and Mader and JS-BACH classifications offer useful information for stratifying cases and provide evidence-based advice on outcome from treatment for patients. Both have been validated in well-defined patient cohorts. [ABSTRACT FROM AUTHOR]

Diagnosis of bone and joint infections can be difficult. In recent years there has been great progress in defining how we diagnose fracture-related infection (FRI) and prosthetic joint infection (PJI). Definitions have been proposed based on the best evidence from the literature, including well-established tests performed before and during surgery. These allow surgeons to make better decisions for treatment and to counsel patients. This paper presents the elements of the International Consensus Definition of FRI and the European Bone & Joint Infection Society Definition of Prosthetic Joint Infection (PJI), together with the current knowledge on how these definitions can help in clinical practice. [ABSTRACT FROM AUTHOR]

Abstract: We give some upper bounds for the spectral radius of bipartite graph and graph, which improve the result in Hong’s Paper [Y. Hong, J.-L. Shu, K. Fang, A sharp upper bound of the spectral radius of graphs, J. Combin. Theory Ser. B 81 (2001) 177–183]. [Copyright &y& Elsevier]

Relationship between the prehistoric human and the surrounding fauna has always been of a complex nature and consisted of material and non-material elements. Sculptural images of animals and birds made of various materials (bone, antler, flint, or wood) are a typical feature of the surviving evidence of the spiritual culture of Mesolithic and Neolithic population in Eastern Europe and the Urals. Realistic and stylized animal images were used to decorate ceremonial and everyday objects including weapons and knives, skis and paddles, axes and wooden utensils. This paper aims to evaluate some patterns in decorative activities and priorities in depicting certain zoomorphic images on an example of small series of Late Mesolithic artefacts from well-known site Zamostje 2, which is located in the Volga-Oka region. Unique preservation conditions in this wetland settlement contributed to accumulation of rich and diverse materials including a large set of decorated objects. This paper focuses on zoomorphic knife handle ends and stylized animal figurines made of bone and wood, which are brought together and considered in this perspective for the first time ever. All knives and pins were involved in production or domestic activities, while some figures carried a non-utilitarian magic function. The site area, obviously, served both for everyday life and for performance of some rites. For the first time for scope of Late Mesolithic settlements, a conclusion is drawn about a possible connection between the image of a duck and a snake. [ABSTRACT FROM AUTHOR]

This work presents the first results from the Aguilón P5 (Zaragoza) cave site on the northern slope of the Iberian System (NE Iberia). The fieldwork carried out since 2010 on several archaeological layers containing remnants of human occupations has revealed lithic remains, processed faunal bones and charred plant remains from combustion events. Due to the lithic tool assemblage and radiocarbon dating (>50.0–41.9 kyr BP), the attribution of this human occupation to the Mousterian techno-complex is clear, contemporary with other important Late Mousterian sites in the Ebro Basin (NE Iberia) and Mediterranean region. Preliminary results concerning stratigraphic, chronometric, techno-tipological and palaeoenvironmental data from the last human occupations of the cave (archaeological layers "cnc", "mcp" and "e") are provided in this paper. To contextualize the Neanderthal occupation of the Aguilón P5 cave, a timeline of Middle Paleolithic in the Iberian System is proposed. A total of 45 dates from 19 stratigraphic units (including speleothems) are available from 10 sites. Chronometric dating series allow us to establish the temporary framework of Mousterian industries in the Iberian System coinciding with the abrupt climate changes related to Heinrich Events which characterize MIS 3. In summary, this paper provides new chronometric and archaeological information about Neanderthal settlement and subsistence in an under-investigated region. [ABSTRACT FROM AUTHOR]

This paper explores how significant are the ecological and climatic variables to influence the stable isotopes of guanacos. Lama guanicoe bone collagen carbon and nitrogen stable isotope ratios are assumed as a macro regional average value in west Argentina, mostly as a baseline to model archaeological human diet. If stable isotopes on mammals reflex ecology and climate, we need to know how those variables influence mammals bone stable isotope ratio. This paper analyses the 13C/12C and 15 N/14N ratio on bone collagen on 122 guanacos from Northwest Patagonia during the Holocene. The results confirm significant variation in both isotopes between Monte and Andean-Patagonian specimens. Guanacos from Monte shows higher δ13C and δ15N than those from Andean-Patagonian. Temporal trends indicate variation through Holocene but this variation is not spatially homogeneous. In this paper we suggest that Medieval Climatic Anomaly had stronger effect in Monte desert than in Patagonia desert, generating driest and/or hottest conditions between 1250 and 600 years BP. Those variations need to be considered to reconstruct human diet at least during the second part of the Holocene. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The osteochondral tissue is an interface between two distinct tissues: articular cartilage and bone. These two tissues are significantly diverse with regard to their chemical compositions, mechanical properties, structure, electrical properties, and the amount of nutrient and oxygen consumption. Thus, transition from the surface of the articular cartilage to the subchondral bone needs to face several smooth gradients. These gradients are imperative to study to generate a scaffold suitable for the reconstruction of the cartilaginous and osseous layers of a defected osteochondral tissue, simultaneously. The aim of this review is to peruse the alternation of biochemical, biomechanical, structural, electrical, and metabolic properties of the osteochondral tissue moving from the surface of the articular cartilage to the subchondral bone. Moreover, this review also discusses currently developed approaches and ideal techniques with a focus on gradients present in the interface of the cartilage and bone. Statement of significance The submitted review paper entitled as "Engineering of the gradient osteochondral tissue: from nature to lab" is a complete review with regard to the osteochondral tissue and transition of different properties between the cartilage and bone tissues. Moreover, previous studies on the osteochondral tissue engineering have been reviewed in this paper. This complete information can be a valuable and useful source for current and future researchers and scientists. Considering the scope of the submitted paper, Acta Biomaterialia would be a suitable journal for publishing this article. [ABSTRACT FROM AUTHOR]

The present paper comprises research results regarding the usage of bone and antler artefacts by the inhabitants of Medieval Moldavia, taking as a case study an assemblage discovered in the medieval site of Old Orhei (Republic of Moldova). Numerous artefacts in different stages of manufacturing were identified, as well as artefacts with different wear levels. Our study emphasizes an important diversity in the typology of artefacts and in the anatomical and taxonomical selection of raw materials. The current paper seeks to continue the analysis of these types of objects that began a decade ago, when a part of bone and antler artefacts recovered from the archaeological excavations conducted in Old Orhei during the years 1947–2001 was investigated. The rich collection of bone and antler objects gained in the last six decades, illustrating the different segments of daily life, represents a valuable testimony of the urban material civilization during this historical period. [ABSTRACT FROM AUTHOR]

A review of recent advances in instrumental methods and techniques for structural and physicochemical characterization of biomaterials and bone tissue is presented in this paper. In recent years, biomaterials attracted great attention primarily because of the wide range of biomedical applications. This paper focuses on the practical aspects of instrumental methods and techniques that were most often applied (X-ray methods, vibrational spectroscopy (IR and Raman), magnetic-resonance spectroscopy (NMR and ESR), mass spectrometry (MS), atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES), thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM)) in the structural investigation and physicochemical characterization of biomaterials and bone tissue. The application of some other physicochemical methods was also discussed. Hands-on information is provided about these valuable research tools, emphasizing practical aspects such as typical measurement conditions, their limitations and advantages, interpretation of results and practical applications. [ABSTRACT FROM AUTHOR]

In the present paper, first results of the influence of the degradation of biodegradable materials on the hardness of the bone are presented in detail. For this purpose, different materials (Mg, Ti and biopolymers) were implanted into the femora of growing rats and bone cross sections were examined for the micro-hardness (MH). The aim of the present paper was to examine the mechanical response of the bone areas surrounding the implant at defined sites and at specified periods after implantation. A special focus was set on Mg alloys. In earlier in-vitro and in-vivo studies, an accumulation of Magnesium in the vicinity of the implant was detected by using different techniques. Therefore, micro-hardness measurements were performed, and the mechanical strength of bone was correlated with the exchange of Magnesium and Calcium in Hydroxyapatite. After the operation and implantation, the micro-hardness values became temporarily lower, but after complete degradation of the implants, the values were identical with those of specimens containing no implants. [ABSTRACT FROM AUTHOR]

Bioceramics have been widely utilized for orthopaedic applications in which the biocompatibility and mechanical properties of the materials are vital characteristics to be considered for their clinical use. Till date, extensive studies have been devoted to developing a range of scientific ways for tailoring the microstructure of bioceramics in order to attain the trade-off of mechanical properties and biocompatibility of the final product. Owing to low reactivity, earlier stabilization and longer functional life of bioceramic, the developed implants are capable of replicating the mechanical behaviour of original bone. As the safety of the patient and its ultimate functionality are the ultimate goal of the selected implant material hence, the present literature survey investigates and brings forth the important aspects associated to the mechanical, biological and microstructural characteristics of bioceramics employed in orthopaedic applications. The review paper majorly focuses on effective utilization of various materials as an additive in bioceramics and processing techniques used for enhancement of properties, enabling the use of material in orthopaedic applications. The influence of various additives on the microstructure, mechanical properties and biological performance of developed bioceramics orthopaedic implants has been elaborately discussed. Furthermore, future prospects are proposed to promote further innovations in bioceramics research. [ABSTRACT FROM AUTHOR]

• Agreement of pre- and post-burn scores of sexual traits is most affected in high intensity burns. • Effects of lower intensity burns in bones are not as innocuous as previously assumed. • Bone heat-induced changes interfere with both metric and morphological sex estimations. The true impact of heat-induced changes in human bone regarding their sex estimation has not been comprehensively documented having a potentially negative impact on forensic anthropology. The objective of this paper was to evaluate how heat exposure affects sex estimation based on both morphological and metric features. The study focused in both low-to-medium intensity burns and high intensity burns. Selected sexually dimorphic features were analysed in 51 experimentally burnt skeletons from the 21st Century Identified Skeletal Collection. Bones were burnt to maximum temperatures between 450 °C and 1050 °C achieved after 75 to 257 min. Morphological methods tested in this study comprised the recommendations for hipbone features from Buikstra and Ubelaker (1994) and from Bruzek (2002). On the other hand, metric references tested here were the ones from Wasterlain (2000), Curate et al. (2016) and Gonçalves et al. (2013) focused on the humerus, femur, calcaneus and talus. Agreement was tested with Gwet's AC1 test and was further assessed by calculating the relative amount of perfect agreements. Results demonstrated that heat-induced changes affected not only the scoring of morphological features burnt at high temperatures but also the scoring of features burnt at lower intensities. On the other hand, metric features were only considerably affected in high intensity burns, no major changes being documented for low-to-medium intensity burns. For low-to-medium intensity burns, the Bruzek and Curate et al. methods revealed a better agreement between the pre- and post-burning scores. For high intensity burns, better agreement was obtained by using the Bruzek (2002) and Gonçalves et al. (2013) methods. As expected, heat-induced warping, fracture and metric change had a major impact on the pre- and post-observations' agreement. Contrary to what has been systematically assumed over the years, this impact is also quite substantial in bones burnt at low-to-medium burn intensities so caution is advised during the analysis of this kind of burnt skeletal material. [ABSTRACT FROM AUTHOR]

Since its discovery in the 1980s, Nahal Hemar Cave has been interpreted as a cult site where ceremonies were performed, as indicated by the extremely selected and highly symbolic repertoire of objects found in the cave (e.g., stone masks, modelled skulls, bone figurines, etc.). The finds, dated to the 8th millennium cal. BC and assigned to the Pre-Pottery Neolithic B (PPNB) period, also consisted of other artefacts often found in contemporaneous sites, such as flint tools or stone beads. In this paper, the status and use of the unique lithic assemblage found in the cave is assessed through a comprehensive approach integrating techno-typological and use-wear analyses and, secondly, contextualized within current lithic research and in the broader context of the Middle/Late PPNB in the southern Levant. The study resolves some of the major questions concerning the production, use and meaning of the flint tools, also bringing some light to the ritual, spiritual or unconventional activities associated with the use of the cave. It concludes that the flint assemblage found in the cave was the result of a series of episodes of deposition of objects over a relatively lengthy period of time, that a varied group of social agents was involved in the production of the said tools and, finally, that the tool producers, and likely, the cave users, were farmers from the agricultural villages in the Mediterranean woodland region. In addition, use-wear analysis indicates that the flint tools found at the cave had a previous history of use before being abandoned/deposited in the cave and some of them may have participated in the ritual activities. Finally, we propose that, in the particular case of the Nahal Hemar knives, they could be related to the processing/dismembering of human bodies, a hypothesis further supported by the remains of 23 individuals (mostly cranial) found in the cave. [ABSTRACT FROM AUTHOR]

This paper presents the conclusions of an archaeometric study on two unique artefacts associated with the Early Bronze Age (EBA) Mierzanowice culture (MC) of south-eastern Poland. Two decorated animal bone pins were found in sepulchral context, each accompanying the skeletal remains of a young woman. Based on previous use-wear analysis, the artefacts are interpreted as clothing pins. Their main characteristic is a geometric decorative pattern in the form of incisions and grooves, filled with a dark, grainy substance. Additionally, one of the pins has a distinct green colouration, which extends over uneroded areas of the surface. An array of imaging and spectrometric techniques was employed to investigate both the inlay and the green staining. While the colouration appears to be post-depositional, the dark substance, identified as fine-grained quartz (possibly raw faience paste) mixed with a black, soot-based pigment (bistre) of adhesive properties, was intentionally applied to the surface of both artefacts. This finding reveals a broad range of skills employed by the craftsperson to manufacture the objects. EBA was a time of emerging specialisation and social stratification, during which local artisans worked within a micro-region producing 'special' items that were both functional and socially meaningful. [ABSTRACT FROM AUTHOR]

Since the FDA approval of Spritam, there has been a growing interest in the application of 3D printing in pharmaceutical science. 3D printing is a method of manufacturing involving the layer-by-layer deposition of materials to create a final product according to a digital model. There are various techniques used to achieve this method of printing including the SLS, SLA, FDM, SSE and PB-inkjet printing. In biomanufacturing, bone and tissue engineering involving 3D printing to create scaffolds, while in pharmaceutics, 3D printing was applied in drug development, and the fabrication of drug delivery devices. This paper aims to review the use of some 3D printing techniques in the fabrication of oral solid dosage forms. FDM, SLA SLS, and PB-Inkjet printing processes were found suitable for the fabrication of oral solid dosage forms, though a great deal of the available research was focused on fused deposition modelling due to its availability and flexibility. Process parameters as well as strategies to control the characteristics of printed dosage forms are analysed and discussed. The review also presents the advantages and possible limitations of 3D printing of medicines. [ABSTRACT FROM AUTHOR]

Fibulo-scapho-lunate fusion is a technique that allows residual movement in the wrist in case of wide bone resection replacing the distal radius by a vascularised fibular transfer. Some authors have used this technique with favourable results but the distal synthesis seems to not be standardised at all, many different osteosynthesis methods have been proposed. This paper reports a complete review of the present day literature about this subject and, evaluating the different proposed osteosynthesis techniques referred in literature, suggests a standardization of the synthesis methods with dorsal plating. We report some technical considerations and results of three cases operated with a stable dorsal osteosynthesis (twice with a double plate and once with a long plate). We evaluate the time of healing and the clinical result. [ABSTRACT FROM AUTHOR]

Objective: Infected mucocele of the paranasal sinuses can induce orbital infection, including orbital subperiosteal abscess, which may lead to life-threatening intracranial complications. Effective diagnosis is important, and treatment should be aggressive. This paper presents our experiences in endoscopic surgical management of orbital complications secondary to infected paranasal sinus mucoceles.Methods: From our retrospective review of the medical charts for 82 patients with 92 sides diagnosed with paranasal sinus mucoceles, we present 7 sides in 7 adult patients with orbital complications secondary to infected mucoceles. The collected data include the suggested etiology, side of sinus involvement, localization of abscess in the orbit, orbital wall bone defects caused by mucocele compression, ophthalmic symptoms, duration between symptom onset and initial visit, operation date, type of surgery performed, and follow-up.Results: The mucocele was located in the ethmoid-frontal region in 9.8% of the sides (9/92), in the frontal sinus in 7.6% (7/92), in the ethmoidal sinus in 9.8% (9/92), in the maxillary sinus in 67.4% (62/92), in the maxillary-ethmoidal sinus in 3.3% (3/92), and in the sphenoid sinus in 2.2% (2/92). The patients with ethmoid-frontal mucoceles had a significantly higher incidence of orbital complications (6/9) as compared with the other sub-types of mucoceles (frontal, 0/7; ethmoidal, 0/9; maxillary, 1/62; maxillary-ethmoidal, 0/3; sphenoid, 0/2). Chandler's classification showed Type I in one, Type II in three, and Type III in three. Sinus involvement was observed at the ethmoid-frontal sinuses in six cases and the maxillary sinus in one case. All seven cases had a partial defect of the orbital wall bone (lamina papyracea, or inferior orbital wall bone) by mucocele compression, and the patients underwent endoscopic marsupialization. For the cases with subperiosteal abscess, the lamina papyracea was also removed partially for draining the abscess. In all cases, symptoms were resolved without any recurrence of the mucocele.Conclusions: Infected ethmoid-frontal mucoceles with a defect of the lamina papyracea tend to induce orbital infection, so prompt surgery for the infected mucoceles should be considered early even with Types I and II, before visual acuity is impaired, because surgery is the only curative treatment for the mucoceles. [ABSTRACT FROM AUTHOR]

• Equal attention was paid to osteogenesis and angiogenesis in vivo and in vitro. • The article focus multiple osteogenic cells for the first time. • Co-culturing cells and performing experiments in immunodeficiency animal. • This paper describes how to verify biological performance of bone substitute. Critical-sized defects (CSDs) caused by trauma, tumor resection, or skeletal abnormalities create a high demand for bone repair materials (BRMs). Over the years, scientists have been trying to develop BRMs and evaluate their efficacy using numerous developed methods. BRMs are characterized by osteogenesis and angiogenesis promoting properties, the latter of which has rarely been studied in vitro and in vivo. While blood vessels are required to provide nutrients. Bone mass maintains a dynamic balance under the joint action of osteolytic and osteogenic activity in which monocytes differentiate into osteolytic cells, and osteoprogenitor cells differentiate into osteogenic cells. This review would be helpful for inexperienced researchers as well as present a comprehensive overview of methods used to investigate the effect of BRMs on osteogenic cells, osteolytic cells, and blood vessels, as well as their biocompatibility and biological performance. This review is expected to facilitate further research and development of new BRMs. [ABSTRACT FROM AUTHOR]

The paper presents the studies of the presence of gamma isotopes and 90 Sr in 19 middle-to old-aged human femur samples. The samples were taken up during routine orthopedic operations in 2012. The aim of the paper was determination of some radionuclides in human bones and estimation of radiation dose created by 90 Sr and 90 Y (in bones). The 137 Cs, 40 K, 226 Ra, 228 Th, 234 Th and 210 Pb isotopes were determined by gamma spectrometry. The above mentioned radionuclide contents were in the ranges: 137 Cs (0.04–1.45); 40 K (13–86); 226 Ra (1–21.5); 228 Th (1.4–40.2); 234 Th (0.4–5.7); 210 Pb (0.7–8.4) Bq/kg d.w. 90 Sr was assayed based on radiometric measurement of ingrown 90 Y. The 90 Sr content was in the range 0.27–1.85 Bq/kg d.w. Measurements of concentration of 90 Sr and 90 Y in bones were used to estimation of health risk by calculation of radiation dose. Adsorbed doses ranged from 2.7· 10 −7 to 1.9 · 10 −6 Gy/y for 90 Sr and from 1.2 · 10 −6 to 8.3 · 10 −7 Gy/y for 90 Y. [ABSTRACT FROM AUTHOR]

The aim of this paper is to identify risk factors associated with the development of osteosynthesis plates' related complications in fibula free flap reconstructions. This is a case series study of consecutive fibula free flaps. Clinical and radiological variables were recorded. Patient outcomes were evaluated with special attention to osteosynthesis plates' related complications; these included plate exposure, plate fracture, loosening of screws, non-union, bone resorption, oro-cutaneous fistulas, and bone exposure. We have done a descriptive analysis, univariate analysis, and multivariate logistic regression model to explore possible risk factors for osteosynthesis plates' related complications. Data analysis was performed using R software (version 3.5.0). 111 fibula free flaps were studied. 29 patients (26.1%) developed osteosynthesis plates' related complications. The mean time to osteosynthesis plates' related complications was 22 months; range (1–120); the median and mode were 12 months. Patients with preoperative radiotherapy (34% vs 14%, p = 0.021), and secondary reconstruction (31% vs 15%, p = 0.053) had a higher incidence of osteosynthesis plates' related complications. In the univariate analysis, "preoperative radiotherapy" (OR 3.07, 95%CI = 1.139–8.242, p = 0.025) and "extraoral soft-tissue defect" (OR 2.907, 95%CI = 1.032–8.088, p = 0.042) were risk factors for osteosynthesis plates' related complications. We have observed an interaction effect: patients with mandibular Brown's classes III + IV and "secondary reconstruction" have a higher risk for osteosynthesis plates' related complications; more than 47.30 times compared to Brown's class I and "primary reconstruction" (p = 0.026). Different factors may contribute to the development of osteosynthesis plates' related complications. Our study adds important information about these. Patients with higher risk of developing complications should be informed that a second intervention to remove the plates might be necessary. [ABSTRACT FROM AUTHOR]

Partially due to the unavailability of ideal bone substitutes, the treatment of large bony defects remains one of the most important challenges of orthopedic surgery. Additively manufactured (AM) biodegradable porous metals that have emerged since 2018 provide unprecedented opportunities for fulfilling the requirements of an ideal bone implant. First, the multi-scale geometry of these implants can be customized to mimic the human bone in terms of both micro-architecture and mechanical properties. Second, a porous structure with interconnected pores possesses a large surface area, which is favorable for the adhesion and proliferation of cells and, thus, bony ingrowth. Finally, the freeform geometrical design of such biomaterials could be exploited to adjust their biodegradation behavior so as to maintain the structural integrity of the implant during the healing process while ensuring that the implant disappears afterwards, paving the way for full bone regeneration. While the AM biodegradable porous metals that have been studied so far have shown many unique properties as compared to their solid counterparts, the unprecedented degree of flexibility in their geometrical design has not yet been fully exploited to optimize their properties and performance. In order to develop the ideal bone implants, it is important to take advantage of the full potential of AM biodegradable porous metals through detailed and systematic study on their biodegradation behavior, mechanical properties, biocompatibility, and bone regeneration performance. This review paper presents the state of the art in AM biodegradable porous metals and is focused on the effects of material type, processing, geometrical design, and post-AM treatments on the mechanical properties, biodegradation behavior, in vitro biocompatibility, and in vivo bone regeneration performance of AM porous Mg, Fe, and Zn as well as their alloys. We also identify a number of knowledge gaps and the challenges encountered in adopting AM biodegradable porous metals for orthopedic applications and suggest some promising areas for future research. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Two degrees of posterior cranial fossa (PCF) maldevelopment can be hypothesized in children with myelomeningocele (MMC). This paper investigates the PCF deformation by quantitative magnetic resonance imaging analysis in MMC subjects with and without Chiari 2 malformation (CM2). PCF bone volume (PCFV), PCF brain volume (PCFBV), lengths of PCF, ventriculomegaly, level, and extension of the dysraphism were analyzed by magnetic resonance image scanning of 51 newborns with MMC surgically repaired at birth (and 41 controls). The possible correlation among PCF hypoplasia, level/extension of the spinal dysraphism, and ventriculomegaly was assessed. In MMC and CM2, the dysraphism level was above L4 in 30 and below L4 in 10 subjects. PCFV/PCFBV ratio and supraocciput and exocciput lengths were significantly reduced; foramen magnum diameters, mammillo-pontine distance, and pons length were significantly increased (P < 0.05). In isolated MMC, the dysraphism level was below L4 in all cases. PCFV/PCFBV ratio and supraocciput length were significantly reduced; pons length was significantly increased (P < 0.05). The lower the MMC level, the lower the incidence of CM2. A positive correlation was found between PCF hypoplasia and MMC level above L4 (P < 0.001), while a negative correlation was found among PCF hypoplasia and MMC extension (P = 0.006), PCF hypoplasia, and ventriculomegaly (P = 0.02). PCF hypoplasia has to be considered a dynamic maldevelopment process in the 2 cohorts rather than 2 separated entities. The level of MMC is the main but not the unique cause influencing the severity of PCF maldevelopment. [ABSTRACT FROM AUTHOR]

• This paper analyses the results of temperature experiments and the different morphologies of bone chips to explore the different machining processes and thermal conditions in conventional and vibration-assisted drilling methods. • Bone chips generated in the three drilling methods under the same drilling parameters were compared quantitatively by their morphology and granularity distribution. • The favourable thermal condition in LFVAD is caused by its unique geometric chip breaking mechanism and cutting/separation motion, which can be verified by its fan-shaped chips. • The dust-like chips from UVAD directly revealed substantial differences in this machining process compared to the other processes and illustrated the additional heat sources associated with this method. When the temperature during bone drilling exceeds the safety threshold, the bone tissue surrounding the drilling site can be irreversibly damaged. To investigate the influence of vibration-assisted drilling (VAD) methods on the temperature increase during bone drilling and the causes for temperature increase, drilling experiments were performed on fresh bovine femur samples. The morphology and granularity distribution of the generated bone chips were innovatively used to directly compare the machining processes and thermal conditions of conventional drilling (CD), low-frequency vibration-assisted drilling (LFVAD), and ultrasonic vibration-assisted drilling (UVAD). The experimental results indicated that LFVAD produced the lowest temperature increase of 31.4°C, whereas UVAD produced the highest temperature increase of 44.1°C with the same drilling parameters. Additionally, the morphologies and granularity distributions of the bone chips significantly differed among these methods. We concluded that the smaller temperature increase in LFVAD was mainly attributed to the improved thermal conditions resulting from the periodic cutting/separation motion and the reliable geometric chip-breaking mechanism. In contrast, the unfavourable thermal conditions of UVAD were caused by the higher applied frequency, which created a significantly larger amount of friction heat. This was the main cause for the highest observed temperature increase, resulting in bone crushing processes that generated additional heat. [ABSTRACT FROM AUTHOR]

Objective : This paper highlights common procedures for establishing a well-constructed FEA problem using a representative dental geometry, and discusses how results can be interpreted to understand the validity of methods and the scope over which the results are valid. Materials and Methods : A representative multi-rooted tooth geometry was generated to study the difference in mesh-density convergence when applying a 1 N occlusal force to a single node versus being distributed over a region. Additionally, a representative tooth-periodontal ligament (PDL)-bone complex was generated with a distributed 500 N occlusal load. PDL Young's modulus values were varied to demonstrate how changing properties influenced simulation outcomes. Results : The mesh density convergence study illustrated the divergent stress response when exposed to a point load as compared to the convergent response using a distributed load. Studying the tooth-PDL-bone complex showed that changing PDL properties had a substantial effect on tooth displacement and maximum stress within the PDL and nearby bone, but had less influence on stresses within the bone farther away from the PDL. Conclusions : The research illustrated the importance of proper FEA problem definition as it pertains to ensuring validity of results and that they truly reflect the overall goals of the analysis. [ABSTRACT FROM AUTHOR]

Craniomaxillofacial injuries account for a large number of emergency attendances and a substantial proportion of the workload of acute clinicians. Although data exist on frequency of involvement of the craniofacial bones, assessments of severity are lacking, and scoring systems for fractures of individual bones and complex craniomaxillofacial trauma often fail to include the frontobasal unit. To rectify this, we have devised a validated scoring system to evaluate the severity of trauma to this region and have merged it with a pre-existing model to create a cohesive craniofacial disruption index. Published papers were reviewed and the frontobasal unit defined. Clinically important anatomical regions were assigned a graduated score that depended on the severity of disruption, and this was applied in the cases of 13 patients with known craniofacial fractures of varying severity. Correlation with existing models was calculated and used as a marker of validity. Our frontobasal system showed strong positive correlation with a consensus of OMFS clinicians (r = 0.783, p < 0.01). When amalgamated with the pre-existing ZS score to create the Craniofacial Disruption Index, it correlated strongly with all previous scoring systems (r ≥0.729, p < 0.001). The index is a user-friendly, validated model that enables comparison of the severity of complex craniofacial injuries. It has many potential uses because of its digital, automated method of calculation. [ABSTRACT FROM AUTHOR]

Bone tissue is composed of organic and inorganic phases with porous and dense regions, which can make it to be considered as a functionally graded body. Therefore, developing an advanced engineering implant with gradual variation in composition or structure that can fulfill the requirement for hard tissue replacement was enthusiastically followed by different researchers. The present paper overviewed the recent investigations on the 3 main types of functionally graded calcium phosphates used for bone substitution. The products features, challenges in preparation procedures and future perspectives were discussed. [ABSTRACT FROM AUTHOR]

This paper reports on the influence of substituting barium (Ba2+) ions on the structural, mechanical and in vitro biological properties of akermanite prepared via high-energy wet planetary ball milling and sintering. The results obtained showed that the properties of the prepared bioceramics are highly dependent on Ba2+ content. It was found that Ba2+ resulted in improved densification (≥90%), and better apatite-forming ability of akermanite ceramic, without altering phase composition. Herein, the enhancement in diametral tensile strength (DTS), Vickers microhardness (H V) and fracture toughness (K IC) for Ba2+-doped akermanite bioceramics are reported for the first time. It was also found that after 21 days of immersion in simulated body fluid (SBF) solution, the doped ceramic surface was completely covered with apatite crystals, indicating Ba2+ encouraged apatite crystals deposition. Therefore, Ba2+-doped akermanite bioceramic could be an attractive alternative bioresorbable material for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

In his book, The Material Theory of Induction , Norton argues that the quest for a universal formal theory or 'schema' for analogical inference should be abandoned. In its place, he offers the "material theory of analogy": each analogical inference is "powered" by a local fact of analogy rather than by any formal schema. His minimalist model promises a straightforward, fact-based approach to the evaluation and justification of analogical inferences. This paper argues that although the rejection of universal schemas is justified, Norton's positive theory is limited in scope: it works well only for a restricted class of analogical inferences. Both facts and quasi-formal criteria have roles to play in a theory of analogical reasoning. • Critical examination of John Norton's "material theory" of analogical inference. • Norton's "bare bones" analysis works well only for some analogical inferences. • Norton's analysis provides limited insight into how analogical arguments work. • We still need quasi-formal theories of analogical reasoning, though not a "logic". [ABSTRACT FROM AUTHOR]

Problems of dispersals of early hominins into Europe are widely discussed. In the Early Pleistocene, the dispersal of mammals and humans from Africa, Asia, and Eastern Europe into the south of Western Europe passed mostly through the Eastern Mediterranean and the Balkans. Data on evolution and distribution of mammal faunas provide a solid basis for correlation and estimation of main dispersal events. In this paper authors made an attempt to analyze the paleobiogeographical aspects of possible hominin dispersals in the mid-Early Pleistocene of the Mediterranean in the context of a broad paleozoogeographical and paleoecological approach to addressing this issue. The study of the Early Pleistocene Trlica TRL11–10 mammal fauna of Trlica cave in Montenegro in the Central Balkans offers valuable information on biotic events in the region, migratory pathways and faunal transformations against a background of alternating environmental conditions. A recent discovery of several unique bones amongst other fossil mammalian remains excavated between 2010 and 2014 from the Trlica TRL11–10 level is of particular interest. The analysis of the assemblage of two large and two small bone artifacts suggests their anthropogenic nature. The Trlica TRL11–10 artifacts may constitute the first evidence of the initial 'Peopling events' in Mediterranean Europe. The artifacts are associated with a very diverse TRL11–10 fauna that includes 34 species of both small and large mammals and belongs to the late Early Pleistocene within the interval 1.8–1.5 Ma, Donau/Eburonian (MIS 63–51). The article emphasizes the close relationship between the early human dispersals and the evolution of biota and the importance of a holistic approach to the study of the problem of dispersals. Paleobiogeographic evidence confirms the possibility of the arrival of early hominins in the Balkans in the mid-Early Pleistocene, prior to 1.5 Ma, very likely closer to the Olduvai time. [ABSTRACT FROM AUTHOR]

The paper presents an innovative osteofixation system designed for bone fracture stabilization. Its special feature, which makes it different from other similar systems, is the possibility to precisely adjust the implant to the shape of the bone. Such a precise adjustment is particularly important in the case of multiple fractures, where proper stabilization is a condition for restoring bone geometry and thus obtaining the biomechanical function of a given segment of the body lost due to fracture. Based on the tested properties of the implant material, the presented system structure was verified for loading, stress, and share forces in multi-site fractures of the mandible. Numerical tests were performed for three different fracture models: unilateral double fracture of the body of mandible, unilateral double fracture of the body and the angle of mandible, and bilateral fracture of the mandible at the angle and body of the mandible. The results indicate that the proposed system may be used to stabilize broken bone fragments successfully, and the obtained stabilization would allow unrestricted use of the chewing function during bone healing and remodeling. The authors point out the advantages of the proposed implantation method thanks to which it is possible to obtain any shape of the implant and thus stabilize bone fragments in any case. [ABSTRACT FROM AUTHOR]

This paper presents new archaeological material and first dates on Upper Pleistocene layers at the site of La Crouzade cave (Gruissan, Aude, France). The site was first excavated by T. and P. Héléna at the beginning of the twentieth century, and the excavations were recently completed during three years (2016–2018) of systematic campaigns. We obtained dates from Middle Palaeolithic layers using two methods: AMS 14C dates were obtained from bone and charcoal, and combined ESR-U series dating was undertaken on horse teeth. Together, these methods allowed us to date this Mousterian sequence to 49,776–44805 cal BP for the deepest level (layer C8) and from 42,000 ± 3000 years BP for the top (layer C6). The Upper Palaeolithic layers are preserved only as patches in the actual excavation area, but a date was obtained from a piece of charcoal collected from a small hearth preserved in the first layer (C5) above Middle Palaeolithic deposits, which indicates an age similar to that of a modern human maxillary previously analysed and re-dated here from 36,014 to 34402 cal BP, confirming its stratigraphic attribution. The Middle Palaeolithic lithics at the site were first described as para-Charentian cultural facies following typological analyses. The revision of the earlier collection supplemented with the new material, using a technological approach, allow to identify two layers dominated by Levallois production followed by discoid production (Layers C8 and C6) surrounding an original assemblage (layer C7), characterised by a dominant Levallois production completed by three secondary production systems of equal importance, including discoid, SSDA and a Quina-like production. The faunal spectrum predominantly comprises an assemblage of Pleistocene large mammals, and biochronological studies corroborate the dates obtained. [ABSTRACT FROM AUTHOR]

The arrival of Modern Humans (MHs) in Europe between 50 ka and 39 ka coincides with significant changes in human behaviour, notably regarding the production of tools, the exploitation of resources and the systematic use of ornaments and colouring substances. The emergence of the so-called modern behaviour is usually associated with MHs, although claims of symbolic thinking in non-MH groups have been advanced in past decades. In this paper, we present a synthesis of the Italian evidence concerning bone tool manufacturing and the use of ornaments and pigments in the time span encompassing the replacement of Neandertals by MHs. Current data show that Mousterian bone tools were mostly obtained from bone fragments used "as is". Conversely an organized production of "finely shaped" bone tools is characteristic of the Uluzzian and the Protoaurignacian, and the complexity inherent in the manufacturing processes suggests that bone artefacts are not to be considered expedient. Some traces of symbolic activities are associated with Neandertals in northern Italy. Ornaments (mostly tusk shells) and pigments used for decorative purposes are well recorded during the Uluzzian. Their features and distribution suggest an intriguing cultural homogeneity within this technocomplex. The Protoaurignacian is characterized by a wider range of archaeological evidence, consisting of personal ornaments (mostly pierced gastropods), pigments and engraved items. [ABSTRACT FROM AUTHOR]

Autonomous vehicles have become a hot spot of the automotive industry, many cities have claimed that autonomous vehicles should be capable of recognizing gestures used by traffic police. Traditional traffic police gesture recognition methods rely on depth-sensor or wearable-devices, which limits their availability in the domain of the intelligent vehicle. Vision-based methods have fewer requirements for distance, but the modeling process is challenging due to the complexity of the visual scenes. Inspired by the recent success in vision-based pose estimation networks such as Convolutional Pose Machine (CPM), in this paper, we propose a novel vision-based human-machine interface to recognize eight kinds of Chinese traffic police gestures and apply it in the real-time recognition tasks. This method integrates a modified CPM network and two kinds of handcrafted features: Relative Bone Length and Angle with Gravity as spatial domain features, and adopt a Long short-term memory (LSTM) network to extract temporal domain features. To train and validate our method, we create a gestures dataset with two hours of traffic police gesture videos, which has 3354 gesture instances. The experiment results show that the proposed method is capable of recognizing traffic police gestures, and is fast enough for online gesture prediction. [ABSTRACT FROM AUTHOR]

In this paper, we carry out an isotopic study to learn about the diet and mobility patterns of the human groups that inhabited different areas and environments of western Catamarca, Argentina, over almost 2500 years. We present and discuss the results of the isotopic composition of 26 bioarchaeological remains (δ13C and δ15N on bone collagen, and δ13C and δ18O on bone apatite) with their respective calibrated absolute dates, from different settings and elevations of the province of Catamarca. They account for the sociocultural development of both the first agropastoral village societies and the Inca society. We also present the regional isotopic context of autochthonous animal and plant food resources. The isotopic composition (δ13C and δ15N on bone collagen) of 47 samples of pre-Hispanic camelids recovered from archaeological sites located at different altitudes of the Fiambalá and Chaschuil regions are studied and discussed. In addition, the δ13C values of 52 native modern and archaeological plant samples are compiled, including samples from the region as well as information from the bibliography. Finally, isotopic analyses of water samples (δ18O) recovered from different environments in the study region are also shown. The data from δ13C and δ15N on bone collagen and δ13C on bone apatite show a high variability of the human diet of the populations of western Catamarca, and suggest that the societies that inhabited the region during the first millennium AD had a balanced diet that combined proteins and carbohydrates, while those dated after the thirteenth century AD reduced their protein intake, which would have significantly affected their health status. The first trends in the δ18O values indicate that individuals had low mobility patterns during their lives, except for some unusual cases of possible non-local individuals. [ABSTRACT FROM AUTHOR]

The paper studies synthetic osteoplastic powder biocomposite, which is bioactive and extremely relevant for bone defect recovery in dentistry and maxillo-facial surgery. Biocomposite fabrication strategy is based on an original sol-gel (template) synthesis of the porous wollastonite containing 30 wt.% of hydroxyapatite. The way to tailor porosity in the material has been proposed involving siloxane-acrylate latex and carbon fibers as pore-forming templates. Phase formation in the composition structure has been investigated by the means of TG/DTA/DSC and XRD. SEM, low temperature nitrogen sorption, and mercury porosimetry has been used to characterize biocomposite's morphology and microstructure. "In vitro" and "In vivo" biocompatibility tests have been carried out. Histological analysis and multislice CT reveal the ability of the biocomposite to integrate into the area of the under-jaw defect (alveolar socket) of the test animal. Blood count assay shows no direct toxic influence of such implants on a living organism. Unlabelled Image • Highly bioactive osteoplastic CaSiO 3 (wollastonite)/HAp powder is prepared. • Original sol-gel (template) strategy enabling to tailor microstructure is shown. • Different kinds of templating agents were used to design porous architecture. • Blood tests showed no toxic impact of the biocomposite on living organism. • "In vivo" studies demonstrated complete implant's integration into under-jaw defect. [ABSTRACT FROM AUTHOR]

Introduction: Surgery of GCTB in sacrum and pelvis is challenging, with high rates of complications and local recurrence. Denosumab can consolidate the peripheral rim of the tumour, thus reducing the rate of morbidities of surgery. The aim of this paper is to evaluate the use of denosumab in pelvic/sacrum giant cell tumours of bone (GCTB).Patients and Methods: We retrospectively reviewed a cohort of 26 patients with aggressive GCTB in sacrum or pelvis treated with denosumab at two referral centres. Clinical response and local recurrence were recorded and the radiologic responses were evaluated with the MDA criteria.Results: 69% of the pelvic GCTB treated with denosumab presented partial or good radiologic responses (type 2A or 2B) after 49 weeks of treatment. Denosumab was administered as adjuvant therapy prior and after surgery in 11 patients (group A), and as the only treatment in 15 patients (group B). In group A, 62% of local recurrence was observed in patients treated with intralesional curettage. No recurrences were identified after en bloc resection. In group B, 9 patients were on continuous bimonthly long term denosumab administration with type 2A and 2B responses. Six patients stopped denosumab and 66% remained stable after 10 months of follow-up.Conclusions: Long-term denosumab therapy can be considered with curative intent for pelvic and sacrum GCTB. If surgical intervention is required wide resection may be advisable to reduce the risk of recurrence. [ABSTRACT FROM AUTHOR]

The composition of large mammal fauna from the Imanay Cave in the Southern Urals (53°02' N, 56°26' E) is described in the present study. The paper aims to provide an preliminary description of the large mammal remains from the Imanay Cave in order to establish their taxonomic status, geological age and to detect the factors that led to accumulation of the bone remains in the cave. An analysis of species composition of vertebrate fauna, archaeological finds and radiocarbon dates has shown that accumulation of fossils in the Imanay Cave spanned the whole period of the Late Pleistocene and Holocene. Remains of the small cave bear (Ursus " savini ") and cave lion (Panthera ex gr. fossilis-spelaea) are prevalent in the Pleistocene groups: 9414 (93%) and 536 (5%) bone specimens, respectively. The cave is the only site in the world where mass bone assemblages of two large terrestrial Carnivora species - small cave bear and cave lion – were found simultaneously. The composition of the skeletal samples for both species was described and the age and sex distributions were determined. Though Mousterian stone tools were found in the cave, no trace of the hunt of the bears and lions by humans was detected. The period during which the accumulation of the fossils took place can be broadly determined as the first half of the Late Pleistocene (MIS5–3). [ABSTRACT FROM AUTHOR]

Recent advances in 3D printing have provided unprecedented opportunities in bone tissue engineering applications for producing a variety of complex patient-specific implants for the treatment of critical-sized bone defects. Natural medicinal compounds (NMCs) with osteogenic potential can be incorporated into these 3D-printed parts to improve bone formation and therefore enhance implant performance. Using NMCs to treat bone-related disorders may prove to be a healthy preventive choice as they are considered safe, have lesser or no side effects, and are more suitable for prolonged use than synthetic drugs. In this review paper, the current challenges of bone tissue engineering are addressed briefly, highlighting the immense potential of NMCs integrated within tissue engineering scaffolds for orthopedic and dental applications. Bone tissue engineering is a promising approach for secondary reconstruction after severe trauma and bone defects. Their importance led to the establishment of 3D-printed bone graft substitutes, including both load bearing and low-load bearing parts, which offer patient-specific defect repair and bone regeneration. Current obstacles in the clinical success of bone graft substitutes led to the establishment of multifunctional grafts, where natural medicinal compounds with osteogenic potential were incorporated in additively manufactured grafts for enhanced osseointegration. Natural medicinal compounds have immense potential towards bone tissue regeneration. Careful investigation of chemical and pharmacological aspects of natural medicinal compounds and their interaction with biomaterials may provide potential directions for researchers in designing scaffolds for bone defect repair. [ABSTRACT FROM AUTHOR]

Down syndrome is the most common chromosomal disorder that affects the life of a person. Early detection of Down syndrome is important and significant for a better assessment of the fetus. The detection can be performed by identifying various parameters from the ultrasound images recorded during the 1st (11-14 weeks) and 2nd trimester (15-22 weeks) of the gestational period. The most important features are short Nasal bone (Hypoplasia) or absence of nasal bone, increased thickness of the back of the neck, fetal heart rate (FHR), crown-rump length (CRL) and shortening of arm bone or thigh-bone. The Diagnosis of Down syndrome is performed using invasive and noninvasive screening tests. There are many reported studies on the diagnosis of Down syndrome. This paper reviews the work on various imaging methods, and a technique reported for the detection of Down syndrome and introduces the use of Deep Learning techniques in identifying the presence of Down syndrome. • Reviews the ultrasound imaging techniques to identify down syndrome. • Reviews the issues related to the diagnosis of down syndrome using ultrasound image. • Reviews the machine learning techniques for detecting the markers of down syndrome. [ABSTRACT FROM AUTHOR]

This paper presents the occurrence of small domestic and wild bird species in medieval assemblages from Hungary. They were present at all types of sites and both in hand retrieved and sieved assemblages, respectively. Nevertheless, the diversity of small birds is twice as large at the high-status settlements as compared to urban and rural sites. Furthermore, small species are represented in a greater number and their remains are more likely to be found in bone assemblages recovered through sieving in addition to recovery by hand. Due to recent excavations first evidence of the blackbird (Turdus merula), the redwing (T. iliacus) and the song thrush (T. philomelos) as well as the largest amount of domestic pigeon (Columba domestica) from medieval Hungarian sites were found. The abundance and spread of the latter species is discussed and illustrated for the first time in this study. [ABSTRACT FROM AUTHOR]

Excavations at Saruq al-Hadid, a late prehistoric (c.2000 BCE – c.800 BCE) site located in the Emirate of Dubai, U.A.E., have recovered several tonnes of animal bone. Due to a thorough sieving and retention strategy the remains of a range of taxa were collected, from camels to rodents. Within this wealth of material several dozen fragments of a variety of bird species were identified that have given a unique insight into human activity in the interior of southeastern Arabia; from sea birds (an unexpected find, given that the site is 40 km away from the current coastline), to a fragment of raptor that might reflect early hunting practices. The presence of certain bird species in the remains may also be indicative of the site's past environment and suggests it was likely different to the sparsely vegetated mobile dune field it is today. This paper outlines these remains, from their excavation to their analysis. The insights they provide into the nature of the occupation at Saruq al-Hadid are discussed, thereby demonstrating the great utility of studying even a relatively small assemblage of archaeological bird remains. [ABSTRACT FROM AUTHOR]

Surgical interventions for congenital scoliosis are challenging for spine surgeons. The coordination of 3-dimensional (3D), real-time, image-guided navigation with an ultrasonic bone cutter allows surgeons to localize the affected area of the spine accurately and remove the lesion without damaging soft tissue structures. The goal of this technical paper is to report a previously undescribed method of hemivertebrectomy that combines 3D, real-time, image-guided navigation and an ultrasonic bone cutter. We highlight the feasibility and safety of this method in spinal surgery. Three patients with congenital scoliosis were treated with this technique. We present three illustrative cases comprising hemivertebrectomies for congenital scoliosis. Intraoperative photos demonstrating the technique are also provided. All surgeries were completed without complications. The hemivertebrae were completely removed, and marked correction of congenital scoliosis was noted. We believe that the combination of 3D, real-time image navigation and an ultrasonic bone cutter improves hemivertebrectomy by increasing accuracy and avoiding dura laceration, major organ damage, or potential vessel damage. [ABSTRACT FROM AUTHOR]

Abstract: Theoretical modeling of bone tissue adaptation started several decades ago. Many important problems have been addressed in this area of research during the last decades. However, many important questions remain unanswered. In this paper, an overview of open problems in theoretical modeling of bone tissue adaptation is presented. First, the principal elements of bone tissue adaptation models are defined and briefly reviewed. Based on these principal elements, four categories of open problems are identified. Two of these categories primarily include forward problems, while two others include inverse problems. In every one of the identified categories, important open problems are highlighted and their importance is discussed. It is shown that most of previous studies on the theoretical modeling of bone tissue adaptation have been focused on the problems of the first category and not much is done in three other categories. The paper tries to highlight these potentially important problems that have been so far largely overlooked and to inspire new avenues of research. [Copyright &y& Elsevier]

Abstract: Maximum intensity projection (MIP) is an important visualization method that has been widely used for the diagnosis of enhanced vessels or bones by rotating or zooming MIP images. With the rapid spread of multidetector-row computed tomography (MDCT) scanners, MDCT scans of a patient generate a large data set. However, previous acceleration methods for MIP rendering of such a data set failed to generate MIP images at interactive rates. In this paper, we propose novel culling methods in both object and image space for interactive MIP rendering of large medical data sets. In object space, for the visibility test of a block, we propose the initial occluder resulting from a preceding image to utilize temporal coherence and increase the block culling ratio a lot. In addition, we propose the hole filling method using the mesh generation and rendering to improve the culling performance during the generation of the initial occluder. In image space, we find out that there is a trade-off between the block culling ratio in object space and the culling efficiency in image space. In this paper, we classify the visible blocks into two types by their visibility. And we propose a balanced culling method by applying a different culling algorithm in image space for each type to utilize the trade-off and improve the rendering speed. Experimental results on twenty CT data sets showed that our method achieved 3.85 times speed up in average without any loss of image quality comparing with conventional bricking method. Using our visibility culling method, we achieved interactive GPU-based MIP rendering of large medical data sets. [Copyright &y& Elsevier]

Bone is a hierarchical, multiphasic and anisotropic structure which in addition possess piezoelectric properties. The generation of piezoelectricity in bone is a complex process which has been shown to play a key role both in bone adaptation and regeneration. In order to understand the complex biological, mechanical and electrical interactions that take place during these processes, several computer models have been developed and used to test hypothesis on potential mechanisms behind experimental observations. This paper aims to review the available literature on computer modeling of bone piezoelectricity and its application to bone adaptation and healing. We first provide a brief overview of the fundamentals of piezoelectricity and bone piezoelectric effects. We then review how these properties have been used in computational models of bone adaptation and electromechanical behaviour of bone. In addition, in the last section, we summarize current limitations and potential directions for future work. • The existing literature on computer modeling of bone piezoelectricity is reviewed. • Classical piezoelectric theory cannot explain the piezoelectric behaviour of bone. • Computer models have described bone piezoelectricity on the remodeling process. • The effect of piezoelectricity on bone regeneration has been shown experimentally. • In silico piezoelectric approaches on bone regeneration remain to be developed. [ABSTRACT FROM AUTHOR]

The microarchitecture of bone tissue presents many features that could act as stress concentrators for the initiation of bone microdamage. This was first identified by John Currey in a seminal paper in 1962 in which he presented the mechanical and biological evidence for stress concentrations at the bone surface, within the bone through the action of stiffness differentials between architectural features including between lamellae, and at the level of the lacunar and canalicular walls. Those early observations set the stage to consider how microscopic damage to bone tissue might affect the properties of bone at a time when most in the scientific community dismissed microcracks in bone as artifact. Evidence collected in the nearly 60 years since those important initial observations suggest that some of these architectural features in bone tissue are more effective as crack arrestors than as crack initiators. Sites of higher mineralization in the bone matrix, particularly interstitial sites in both cortical and trabecular bone, may serve preferentially as locations for crack initiation, whereas those boundaries identified by Currey as both stress concentrators and stress arrestors are more effective at stopping cracks than at initiating them. • John Currey identified stress concentrators and stress arrestors in bone nearly 60 years ago. • Evidence collected since indicate some of these architectural features are more effective crack arrestors than initiators. • Highly mineralized bone matrix, rather than stress concentration per se, may be effective stress concentrators. [ABSTRACT FROM AUTHOR]

• 75 bone samples from different time periods have been analyzed, the extracts obtained varied in DNA quantity and quality. • Y-STR haplotypes were obtained from samples by CE allele calling (YFiler Plus PCR Amplification Kit) and MPS (ForenSeq Signature DNA Prep Kit). • Differences in amplification rates were found within common markers. There was an allele call disconcordance in one sample. • Significant number of variants have been found by sequence analysis of repetitive and flanking regions of the Y-STRs. Forensic and population genetics often rely on Y-chromosomal studies. Whether it is a human identification case, trace evidence examination or phylogenetic analysis, a Y-STR haplotype is an important tool in the hands of law enforcement agencies. A common obstacle in achieving satisfactory results in all of the above mentioned circumstances, is low DNA quantity and quality within samples obtained. In this study we have examined Y-STR haplotypes in 75 bone material samples, coming from different time periods. For this purpose we have chosen YFiler Plus PCR Amplification Kit (ThermoFisher Scientific) and ForenSeq Signature DNA Prep Kit (Verogen Inc.), which use two different allele calling technologies – capillary electrophoresis and Massively Parallel Sequencing respectively. Full profiles were obtained from DNA extracts with as little as 0.1896 ng (Degradation Index 1.3) (ForenSeq) and 0.0591 ng (Degradation Index 26.8) (YFiler Plus) DNA input. The results that we present in this paper show differences in amplification rates between common markers in both kits. The differences strictly reflect mean amplicon length of markers. This, however, does not seem to influence Y-haplogroup estimation results noticeably. In one sample a discordance occurred between haplotypes obtained with both methods, where a 24 allele was called in DYS390 marker by capillary electrophoresis, while for the same sample in this locus a 23 allele was shown with MPS. A reason for this is yet to be investigated. The sequence analysis revealed a significant variation between isometric alleles, especially within repetitive regions of studied Y-STR markers. [ABSTRACT FROM AUTHOR]

Denosumab is one of the most commonly prescribed anti-resorptive drugs for the treatment of postmenopausal osteoporosis. The therapeutic effect of denosumab is to inhibit osteoclast differentiation and consequently bone resorption. Gains in bone mineral density (BMD) are achieved based on the ability of the bone matrix to undergo secondary mineralization. Experimental data show that the increase of BMD after commencing denosumab treatment are bone site specific. In this paper, we developed a comprehensive mechanistic pharmacokinetic-pharmacodymamic (PK-PD) model of the effect of denosumab on bone remodeling in postmenopausal osteoporosis (PMO). The PD model is based on a bone cell population model describing the bone remodeling process at the tissue scale. The conceptual model of the bone mineralization process, originally proposed by Boivin and Meunier, is quantitatively incorporated using a FIFO (First-In-First-Out) queue algorithm. The latter takes into account the balance of mineral within bone tissue due to the mineralization process, distinguishing the primary and secondary phases and removal of bone matrix due to bone resorption. The numerical simulations show that the model is able to predict the bone-site specific increase in BMD as was observed in the experimental data of Bone et al. 2008 for a typical denosumab administration pattern of 60 mg every 6 months. At the hip a 5 % increase in BMD was observed, while at the lumbar spine a 7.5 % increase of BMD was achieved after a 2 year treatment period. The difference in BMD is due to the fact that bone turnover at the hip is lower compared to lumbar spine and consequently has less potential for secondary mineralization. Parametric studies revealed that the rate of bone mineralization is an essential parameter regulating BMD gains. If mineralization is neglected only minimal increases in BMD are observed. • Mineralization is an essential mechanism for bone density gain (BDG) after treatment with denosumab. • Mineralization rate strongly affects the changes in BDG over time. High values lead to earlier saturation. • The slope of BDG vs. time curves is increased with turnover rate. • The drug accessibility factor is essential in controlling how denosumab is distributed from the serum to the bone tissue compartment. • The effect of denosumab on BDG is site specific, being more effective in the lumbar spine than in the hip. [ABSTRACT FROM AUTHOR]

The Göttingen minipig has been used as a surrogate in impact experiments designed to better understand the mechanisms by which mechanical loading induces traumatic brain injury (TBI). However, the relationship between mechanical response and structural morphology of the minipig cranium must be understood relative to the human skull in order to accurately scale any quantitative results, such as injury thresholds, from non-human TBI experiments to the human anatomy. In this study, bone specimens were dissected from the crania of adolescent Göttingen minipigs. These specimens were small cubes that contained the entire thickness of the skull. The microstructure of these skull specimens was quantified at the micron-length scale using micro-computed tomography (micro-CT). The skull was found to be highly porous near the skin-side surface and became less porous nearer the brain-side surface. The skull specimens were then loaded in quasi-static compression to obtain their mechanical response. The surface strain distribution on the specimen face was measured during loading using digital image correlation (DIC). The 2-D strain field formed a gradient of iso-strain bands along the thickness (depth) dimension from the skin-most to brain-most sides of the skull. The variation of the minipig microstructure along the thickness differed significantly from that of the adult human skull; thus the mechanical load transmission through the minipig skull is expected to be quite different from that of the human skull. The objective was to develop the methodology of relating the microstructure, as quantified by the bone volume fraction (BVF), to the mechanical response. The specimen was modeled by discretizing the depth dimension into a series of layers, which enabled the calibration of a power law relating the depth-dependent BVF to the depth-varying modulus. The relationship was used to predict moduli values for the adolescent minipig skull to provide updated, biofidelic parameters for finite element simulations at varying levels of complexity. Moreover, the methodology outlined in this paper can be applied to other skulls with different structural variations, such as the human. Image 1 • Characterized morphology of minipig skull with high-resolution micro-CT. • Minipig skull bone denser nearer brain, more porous near skin. • Measured variation of modulus as a function of skull depth. • Obtained relationship between modulus and local morphology. • Determined depth-dependent modulus of skull bone for finite element simulations. [ABSTRACT FROM AUTHOR]