Search results for: fracture length

Authors: D. P. Rajesh, H. N. Anjanayappa, P. Nayana, S. Benakappa

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The present study deals with length-weight relationship of Atropus atropos for which no information is available on this aspect from Mangalore coast. Therefore the present investigation was undertaken. Fish samples were collected from fish landing center (Mangalore) and fish market. The regression co-efficient of male was found to be lower than female. From this observation it may be opined that female gained more weight with increase in length compared to male. Data on seasonal variation in condition factor (Kn) showed that Kn values were more or less similar in both the sexes, indicating almost identical metabolic activity. Gonadal development and high feeding intensity are the factors which influenced the condition factor. The seasonal fluctuations in the relative condition factor of both the sexes could be attributed to the sexual cycle, food intake and environmental factors. From the present study, it can be inferred that the variation in the condition of Atropus atropos was due to feeding activity and gonadal maturity.

Keywords: Atropus atropos, length-weight relationship, Mangalore coast, relative condition factor, Kn

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Authors: M. Benachour, N. Benachour, M. Benguediab

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In this investigation, variation of cyclic loading effect on fatigue crack growth is studied. This study is performed on 2024 T351 and 7050-T74 aluminum alloys, used in aeronautical structures. The propagation model used in this study is NASGRO model. In constant amplitude loading (CA), the effect of stress ratio has been investigated. Fatigue life and fatigue crack growth rate were affected by this factor. Results showed an increasing in fatigue crack growth rates (FCGRs) with increasing stress ratio. Variable amplitude loading (VAL) can take many forms i.e with a single overload, overload band etc. The shape of these loads affects strongly the fracture life and FCGRs. The application of a single overload (ORL) decrease the FCGR and increase the delay crack length caused by the formation of a larger plastic zone compared to the plastic zone due without VAL. The fatigue behavior of the both material under single overload has been compared.

Keywords: fatigue crack growth, overload ratio, stress ratio, generalized willenborg model, retardation, al-alloys

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Authors: Pakize Ozlem Kurt Polat, Gizem Metin, Koksal Yagdi

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In order to evaluate the effect of the different sources of salt on germination and early growth of five wheat cultivars (Katea, Bezostaja, Koksal-2000, Golia, Pehlivan) an experiment was conducted at the seed laboratory of the Uludag University, Agricultural Faculty, Department of Field Crops in Bursa/Turkey. Seeds were applied in five different resources media (KCl % 2, KCl %4, KNO₃ %0,5, KH₂PO₄ %0,5, PEG %10) and distilled water as the control). The seed was fully immersed in priming media at a temperature of 24ᵒC for durations of 12 and 24hours. Six different agronomic characters (seed germination, stem length, stem weight, radicle length, fresh weight, dry weight) were measured in 7th days and 14th days. Maximum seed germination percentage of seven days are Pehlivan was observed when the seeds were applied by KH₂PO₄ and Katea by distilled water as a control. The most stem length and stem weight were obtained for seeds were applied by KH₂PO₄ %0,5 with Katea and Bezostja immersed in priming media at 12h intervals beginning 7d after planting. Seeds were applied KH₂PO₄ %0,5 media produced maximum radicle length by Koksal and dry weight by Katea. The freshest weight obtains in Katea by KNO₃ %0,5 immersed in priming media at 24h. The most germination percent, dry weight, stem length of fourteen days was observed in Katea which subjected to KH₂PO₄ %0,5 solution. The most radicle length was observed Katea and Koksal in media of KH₂PO₄ %0,5. The most stem length was obtained for seeds were applied by KH₂PO₄ %0,5 and KNO₃ with Katea and Bezostaja. When the applied chemicals and all days examined KH₂PO₄ %0,5 treatment in fourteen days and immersed for the duration of 24 hours had better effects than other medias, seven days treatments and 12hours immersed. As a result of this research, the best response of media for the wheat germination can be said that the KH₂PO₄ %0,5 immersed in priming media at 24h intervals beginning 14 days after planting.

Keywords: germination, priming, seedling growth, wheat

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Authors: V. Hashim, P. N. Dileep

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Stent implantation is being seen as the most successful method to treat coronary artery diseases. Different types of stents are available in the market these days and the success of a stent implantation greatly depends on the proper selection of a suitable stent for a patient. Computer numerical simulation is the cost effective way to choose the compatible stent. Studies confirm that the design characteristics of stent do have great importance with regards to the pressure it can sustain, the maximum displacement it can produce, the developed stress concentration and so on. In this paper different designs of stent were analyzed together with balloon to optimize the stent and balloon system. Commercially available stent Palmaz-Schatz has been selected for analysis. Abaqus software is used to simulate the system. This work is the finite element analysis of the artery stent implant to find out the design factors affecting the stress and strain. The work consists of two phases. In the first phase, stress distribution of three models were compared - stent without balloon, stent with balloon of equal length and stent with balloon of extra length than stent. In second phase, three different design models of Palmaz-Schatz stent were compared by keeping the balloon length constant. The results obtained from analysis shows that, the design of the strut have strong effect on the stress distribution. A design with chamfered slots found better results. The length of the balloon also has influence on stress concentration of the stent. Increase in length of the balloon will reduce stress, but will increase dog boning effect.

Keywords: coronary stent, finite element analysis, restenosis, stress concentration

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Authors: William Elnemer, Nauman Hussain, Samir Al-Ali, Henry Shu, Diane Ghanem, Babar Shafiq

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Introduction: The incidence of infection in open tibial shaft injuries varies depending on the severity of the injury, with rates ranging from 1.8% for Gustilo-Anderson type I to 42.9% for type IIIB fractures. The timely administration of antibiotics upon presentation to the emergency department (ED) is an essential component of fracture management, and evidence indicates that prompt delivery of antibiotics is associated with improved outcomes. The objective of this study is to identify factors that contribute to the expedient administration of antibiotics. Methods: This is a retrospective study of open tibial shaft fractures at an academic Level I trauma center. Current Procedural Terminology (CPT) codes identified all patients treated for open tibial shaft fractures between 2015 and 2021. Open fractures were identified by reviewing ED and provider notes, and with ballistic fractures were considered open. Chart reviews were performed to extract demographics, fracture characteristics, postoperative outcomes, time to operative room, time to antibiotic order, and delivery. Univariate statistical analysis compared patients who received early antibiotics (EA), which were delivered within one hour of ED presentation, and those who received late antibiotics (LA), which were delivered outside of one hour of ED presentation. A multivariate analysis was performed to investigate patient, fracture, and transport/ED characteristics contributing to faster delivery of antibiotics. The multivariate analysis included the dependent variables: ballistic fracture, activation of Delta Trauma, Gustilo-Andersen (Type III vs. Type I and II), AO-OTA Classification (Type C vs. Type A and B), arrival between 7 am and 11 pm, and arrival via Emergency Medical Services (EMS) or walk-in. Results: Seventy ED patients with open tibial shaft fractures were identified. Of these, 39 patients (55.7%) received EA, while 31 patients (44.3%) received LA. Univariate analysis shows that the arrival via EMS as opposed to walk-in (97.4% vs. 74.2%, respectively, p = 0.01) and activation of Delta Trauma (89.7% vs. 51.6%, respectively, p < 0.001) was significantly higher in the EA group vs. the LA group. Additionally, EA cases had significantly shorter intervals between the antibiotic order and delivery when compared to LA cases (0.02 hours vs. 0.35 hours, p = 0.007). No other significant differences were found in terms of postoperative outcomes or fracture characteristics. Multivariate analysis shows that a Delta Trauma Response, arrival via EMS, and presentation between 7 am and 11 pm were independent predictors of a shorter time to antibiotic administration (Odds Ratio = 11.9, 30.7, and 5.4, p = 0.001, 0.016, and 0.013, respectively). Discussion: Earlier antibiotic delivery is associated with arrival to the ED between 7 am and 11 pm, arrival via EMS, and a coordinated Delta Trauma activation. Our findings indicate that in cases where administering antibiotics is critical to achieving positive outcomes, it is advisable to employ a coordinated Delta Trauma response. Hospital personnel should be attentive to the rapid administration of antibiotics to patients with open fractures who arrive via walk-in or during late-night hours.

Keywords: antibiotics, emergency department, fracture management, open tibial shaft fractures, orthopaedic surgery, time to or, trauma fractures

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Authors: Tauhidur Rahman, Subhrajit Pathak

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In this study, structural response of Bhairabi-Sairang Tunnel due to presence of seismic faults has been thoroughly examined. There may be several active faults located in and around the project. Faults are the key seismic sources from where earthquakes are originated. The magnitude of earthquake will depend on the length of the fault. A long fault more than 200 km can produce earthquake of magnitude (Mw ) more than 8.0 and smaller length less than 10 km will produce small magnitude earthquake. Now-a-days it is very much essential to identify the distance and length of a fault from the project site. Based on this, in the present paper, a case study of the Bhairabi Sairang Tunnel of 1.73 Km length located in the North Eastern Region of India has been selected to calculate the seismic hazard from the surrounding effect of faults. A comparative study of seismic hazard at the tunnel site has been made based on the location of faults with the seismic hazard obtained from the Indian Standards code of Practice. In this paper, a practical problem of a tunnel has been analysed based on the available faults around the project site accounting the soil factor.

Keywords: seismic hazard, effect of fault, soil factor, Bhairabi Sairang tunnel

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Authors: Petr Homola, Roman Růžek

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Laser beam micro-drilling (LBMD) is one of the most important non-contact machining processes of materials that are difficult to machine by means oeqf conventional machining methods used in various industries. The paper is focused on LBMD knock-down effect on Ti-6Al-4V (Grade 5) titanium alloy sheets properties. Two various process configurations were verified with a focus on laser damages in back-structure parts affected by the process. The effects of the LBMD on the material properties were assessed by means of tensile and fatigue tests and fracture surface analyses. Fatigue limit of LBMD configurations reached a significantly lower value between 15% and 30% of the static strength as compared to the reference raw material with 58% value. The farther back-structure configuration gives a two-fold fatigue life as compared to the closer LBMD configuration at a given stress applied.

Keywords: fatigue, fracture surface, laser beam micro-drilling, titanium alloy

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Authors: Tahir Khaleeq, Patrick Lancaster, Keji Fakoya, Pedro Ferreira, Usman Ahmed

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Introduction: Virtual fracture clinics (VFC) have been shown to be a safe and cost-effective way of managing outpatient referrals to the orthopaedic department. During the coronavirus pandemic there has been a push to reduce unnecessary patient contact whilst maintaining patient safety. Materials and Methods: A protocol was developed by the clinical team in collaboration with Advanced Physiotherapy Practitioners (APP) on how to manage common musculoskeletal presentations to A&E prior to COVID as part of routine service development. Patients broadly triaged into 4 categories; discharge with advice, referral to VFC, referral to face to face clinic or discussion with on call team. The first 9 months of data were analysed to assess types of injury seen and outcomes. Results: In total 2489 patients were referred to VFC from internal and external sources. 734 patients were discharged without follow-up and 182 patients were discharged for physiotherapy review. Only 3 patients required admission. Regarding follow-ups, 431 patients had a virtual follow-up while 1036 of patients required further face to face follow up. 87 patients were triaged into subspecialty clinics. 37 patients were felt to have been referred inappropriately. Discussion: BOA guidelines suggest all patients need to be reviewed within 72 hours of their orthopaedic injury. Implementation of a VFC allows this target to be achieved and at the same time reduce patient contact. Almost half the patients were discharged following VFC review, the remaining patients were appropriately followed up. This is especially relevant in the current pandemic where reducing unnecessary trips to hospital will benefit the patient as well as make the most of the resources available.

Keywords: virtual fracture clinic, lockdown, trauma and orthopaedics, Covid- 19

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Authors: A. M. Daneshian Moghaddam, A. H. Hosseinzadeh, A. Bandehagh

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To investigate the effect of cadmium heavy metal stress on five ecotype of dill, this experiment was conducted in the greenhouse of Tabriz University and Shabestar Islamic Azad University’s laboratories with tree replications. After growing the plants, cadmium treatments (concentration 0,300, 600 µmol) were applied. The essential oil of the samples was measured by hydro distillation and using a Clevenger apparatus. Variables used in this study include: wet and dry roots and aerial part of plant, plant height, stem diameter, and root length. The results showed that different concentrations of heavy metal has statistical difference (p < 0.01) on the fresh weight, dry weight, plant height and root length but hadn’t significant difference on essential oil percentage and root length. Dill ecotypes have statistical significant difference on essential oil percent, fresh plant weight, plant height, root length, except plant dry weight. The interactions between Cd concentration and dill ecotypes have not significant effect on all traits, except root length. Maximum fresh weight (4.98 gr) and minimum amount (3.13 gr) were obtained in control trait and 600 ppm of cd concentration, respectively. Highest amount of fresh weight (4.78 gr) was obtained in Birjand ecotype. Maximum plant dry weight (1.2 gr) was obtained at control. The highest plant height (32.54 cm) was obtained in control and with applies cadmium concentrations from zero to 300 and 600 ppm was found significantly reduced in plant height.

Keywords: pollution, essential oil, ecotype, dill, heavy metals, cadmium

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Authors: Naresh Radaliyagoda, Nigel M. Jennett, Rong Lan, David Parfitt

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A series of length scale engineered multilayer material with temperature robust mechanical properties has been suggested. A range of polycrystalline copper sub-layers with the thickness varying from 1 to 25μm and buried in between two nickel layers was produced using electrodeposition dual bath technique. The structure of the multilayers was characterized using Electron Backscatter Diffraction and Scanning Electron Microscope. The interface effect on the hardness and elastic modulus was tested using Nano-indentation. Results of the grain size and layer thickness measurements, and indentation hardness have been compared. It is found that there is a combined length scale effect that improves mechanical properties in Ni/Cu multilayer structures.

Keywords: nano-indentation, size effect, multilayers, electrodeposition

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Authors: Jung-Ho Moon, Tae Kwon Ha

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M2 steels, the typical Co-free high speed steel (HSS) possessing hardness level of 63~65 HRc, are most widely used for cutting tools. On the other hand, Co-containing HSS’s, such as M35 and M42, show a higher hardness level of 65~67 HRc and used for high quality cutting tools. In the fabrication of HSS’s, it is very important to control cleanliness and eutectic carbide structure of the ingot and it is required to increase productivity at the same time. Production of HSS ingots includes a variety of processes such as casting, electro-slag remelting (ESR), forging, blooming, and wire rod rolling processes. In the present study, electro-slag rapid remelting (ESRR) process, an advanced ESR process combined by continuous casting, was successfully employed to fabricate HSS billets of M2, M35, and M42 steels. Distribution and structure of eutectic carbides of the billets were analysed and cleanliness, hardness, and composition profile of the billets were also evaluated.

Keywords: high speed tool steel, eutectic carbide, microstructure, hardness, fracture toughness

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Authors: Wiwin Tyas Istikowati, Futoshi Ishiguri, Haruna Aisho, Budi Sutiya, Imam Wahyudi, Kazuya Iizuka, Shinso Yokota

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The objective of this study was to investigate the anatomical characteristics of three native fast-growing species, terap (Artocarpus elasticus Reinw. ex Blume), medang (Neolitsea latifolia (Blume) S. Moore), and balik angin (Alphitonia excelsa (Fenzel) Reissek ex Benth) growing in the secondary forest in South Kalimantan, Indonesia for evaluating the possibility of tree breeding for wood quality. Cell lengths were investigated for 5 trees in each species at several different height positions (1.0, 3.0, 5.0, 7.0, 9.0, and 11.0 m above the ground). The mean values of fiber and vessel element lengths in terap, medang, and balik angin were 1.52 and 0.44, 1.16 and 0.53, and 1.02 and 0.49 mm, respectively. Fiber length in terap and balik angin gradually increased from pith to bark, whereas it increased up to 2 cm and then became nearly constant to the bark in medang. Vessel element length was almost constant from pith to bark in terap and balik angin, while slightly increased from pith to bark in medang. Fiber length in terap has a fluctuation pattern from ground level to top of the tree. It decreased up to 3 m above the ground, increased up to 5 m, and then decreased to the top of the tree. On the other hand, vessel element length slightly increased up to 5 m above the ground, and then decreased to the top of the tree. Both fiber and vessel element lengths in medang were almost constant from ground level to top of the tree, whereas decreased from ground level to top of the tree in balik angin. Significant difference at 1% level among trees was found in both fiber and vessel element length in both radial and longitudinal directions for terap and medang. Based on obtained results, it is concluded that the wood quality in fiber and vessel element lengths of terap and medang can be improved by tree breeding programs.

Keywords: anatomical properties, fiber length, vessel elements length, fast-growing species

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Authors: C. G. Shashi Kumar, G. Arun Maiya, H. Manjunath Hande, K. V. Rajagopal

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Background: Diabetes mellitus (DM) is a metabolic disorder with involvement of neurovascular and muscular system. Studies have documented that the gait parameter is altered in type 2 diabetes mellitus with peripheral neuropathy. However, there is a dearth of literature regarding the gait characteristics in type 2 diabetes mellitus (T2DM) without peripheral neuropathy. Therefore, the present study is focused on identifying gait changes in early type 2 diabetes mellitus without peripheral neuropathy. Objective: To analyze the gait characteristics in Type 2 diabetes mellitus without peripheral neuropathy. Methods: After obtaining ethical clearance from Institutional Ethical Committee (IEC), 36 T2DM without peripheral neuropathy and 32 matched healthy subjects were recruited. Gait characteristics (step duration, gait cycle length, gait cycle duration, stride duration, step length, double stance duration) of all the subjects were analyzed using Windtrack dynamic foot scanner. Data were analyzed using Independent‘t’ test to find the difference between the groups (step duration, gait cycle length, gait cycle duration) and Mann-Whitney test was used to analyze the step length and double stance duration to find difference between the groups. Level of significance was kept at P<0.05. Results: Result analysis showed significant decrease in step duration, gait cycle length, gait cycle duration, step length, double stance duration in T2DM subjects as compared to healthy subjects. We also observed a mean increase in stride duration in T2DM subjects compared to healthy subjects.

Keywords: type 2 diabetes mellitus, dynamic foot scan, gait characteristics, medical and health sciences

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Authors: Sallah S. El-Ammari, Mona. S. Hasan

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This research is aimed to study allelopathic effects of two wind breakers Eucalyptus camaldulensis and E.gomphocephala on germination and growth of barley using aqueous extracts of leaves at 0.5, 1, 5, and 10% concentrations for treatment of barley caryopsis in petri dishes incubated in growth chamber. Distilled water was used in the experiment as a control. Seed germination was recorded on daily basis for five days. After ten days measurements of root length, shoot length, fresh and dry weight of root and shoot were taken. With the exception of 0.5% E. gomphocephala extract effect on length and dry weight of barley root, all the tested extract concentrations for both eucalyptus species significantly decreased the percent and speed of germination, root and shoot length, fresh and dry weight of root and shoot of barley compared to the control. For both species the allelopathic effect was significantly increasing with the increase of the extract concentration. Although, higher allelopathic effect was shown by E. camaldulensis, the results indicating that both eucalyptus species should not be recommended as wind breakers for barley fields.

Keywords: allelopathy, eucalyptus, barley, Libya

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Authors: Ravinu Garg, Naresh V. Datla

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We study the fracture mechanics of peeling of thin films perfectly bonded to a rigid substrate of any random surface topology using an analytical formulation. A generalized theoretical model has been developed to determine the peel strength of thin elastic films. It is demonstrated that an improvement in the peel strength can be achieved by modifying the surface characteristics of the rigid substrate. Characterization study has been performed to analyze the effect of different parameters on effective peel force from the rigid surface. Different surface profiles such as circular and sinusoidal has been considered to demonstrate the bonding characteristics of film-substrate interface. Condition for the instability in the debonding of the film is analyzed, where the localized self-debonding arises depending upon the film and surface characteristics. This study is towards improved adhesion strength of thin films to rigid substrate using different textured surfaces.

Keywords: debonding, fracture mechanics, peel test, thin film adhesion

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Authors: Jasvinder Singh, Manjinder Singh

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Welding of dissimilar materials is a complicated process due to the difference in melting point of two materials. Thermal conductivity and coefficient of thermal expansion of dissimilar materials also different; therefore, residual stresses produced in the weldment and base metal are the most critical problem associated with the joining of dissimilar materials. Tensile strength and impact toughness also reduced due to the residual stresses. In the present research work, an attempt has been made to weld SS304 and MS1018 dissimilar materials by submerged arc welding (SAW). By conducting trail, runs most effective parameters welding current, Arc voltage, welding speed and nozzle to plate distance were selected to weld these materials. The fractional factorial technique was used to optimize the welding parameters. Effect on tensile strength (TS), fracture toughness (FT) and microhardness of weldment were studied. It was concluded that by optimizing welding current, voltage and welding speed the properties of weldment can be enhanced.

Keywords: SAW, Tensile Strength (TS), fracture toughness, micro hardness

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Authors: Issa M. Hweidi, Saba W. Al-Ibraheem

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This study aimed to assess the increased hospital length of stay and healthcare costs associated with SSIs among ventriculoperitoneal shunting surgery patients in Jordan. This study adopted a retrospective and nested 1:1 matched case-control design. A non-probability convenient sample of 48 VP shunt patients was recruited for the purpose of the study. The targeted groups of the study basically used to cross-match the variables investigated to minimize the risk of confounding. Information was extracted from the text of patients' electronic health records. As compared to the non-SSI group, the SSI group had an extra mean healthcare cost of $13,696.53 (p=0.001) and longer hospital length of stay (22.64 mean additional days). Furthermore, Acinetobacter baumannii and Klebsiella pneumonia were identified as being the most predominant causative agents of SSIs. The results of this study may provide baseline data for national and regional benchmarking to evaluate the quality of care provided to likewise patients. Adherence to infection control strategies and protocols considering new surveillance methods of SSIs is encouraged.

Keywords: ventriculoperitoneal shunt, health care cost, length of stay, neurosurgery, surgical site infections

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Authors: Dae Kyung Choi, Won Man Park, Kyungsoo Kim, Yoon Hyuk Kim

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The interspinous process devices have been recently used due to its advantages such as minimal invasiveness and less subsidence of the implant to the osteoporotic bone. In this paper, we have analyzed the influences of ligature tightening of several interspinous process devices using finite element analysis. Four types of interspinous process implants were inserted to the L3-4 spinal motion segment based on their surgical protocols. Inferior plane of L4 vertebra was fixed and 7.5 Nm of extension moment were applied on superior plane of L3 vertebra with 400N of compressive load along follower load direction and pretension of the ligature. The stability of the spinal unit was high enough than that of intact model. The higher value of pretension in the ligature led the decrease of dynamic stabilization effect in cases of the WallisTM, DiamTM, Viking, and Spear®. The results of present study could be used to evaluate surgical option and validate the biomechanical characteristics of the spinal implants.

Keywords: interspinous process device, bone fracture risk, lumbar spine, finite element analysis

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Authors: Eyal Rosen

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This study is aimed to report a possible effect of the presence of dental implants on the development of crown or root fractures in adjacent natural teeth. A series of 26 cases of teeth diagnosed with crown or root fractures following the placement of adjacent dental implants is presented. In addition, a comprehensive systematic review of the literature was performed to detect other studies that evaluated this possible complication. The case series analysis revealed that all crown-fractured teeth were non-endodontically treated teeth (n=18), and all root fractured teeth were endodontically treated teeth (n=8). The time from implant loading to the diagnosis of a fracture in an adjacent tooth was longer than 1 year in 78% of cases. The majority of crown or root fractures occurred in female patients, over 50 years of age, with an average age of 59 in the crown fractures group, and 54 in the root fractures group. Most of the patients received 2 or more implants. Nine (50%) of the teeth with crown fracture were molars, 7 (39%) were mandibular premolars, and 2 (11%) were incisor teeth. The majority of teeth with root fracture were premolar or mandibular molar teeth (6 (75%)). The systematic review of the literature did not reveal additional studies that reported on this possible complication. To the best of the author’s knowledge this case series, although limited in its extent, is the first clinical report of a possible serious complication of implants, associated fractures in adjacent endodontically and non-endodontically treated natural teeth. The most common patient profile found in this series was a woman over 50 years of age, having a fractured premolar tooth, which was diagnosed more than 1 year after reconstruction that was based on multiple adjacent implants. Additional clinical studies are required in order to shed light on this potential serious complication.

Keywords: complications, dental implants, endodontics, fractured teeth

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Authors: S. Gupta, R. Sarkar, S. Pathak, D. H. Kela, A. Pramanick, P. Talukdar

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Low alloy quenched and tempered steels are typically used in cast railway components such as knuckles, yokes, and couplers. Since these components experience extensive impact loading during their service life, adequate impact toughness of these grades need to be ensured to avoid catastrophic failure of parts in service. Because of the general availability of Charpy V Test equipment, Charpy test is the most common and economical means to evaluate the impact toughness of materials and is generally used in quality control applications. With this backdrop, an experiment was designed to evaluate the effect of austenitizing temperature, soaking time and resultant grain size on the Charpy impact toughness and the related fracture mechanisms in a quenched and tempered low alloy steel, with the aim of optimizing the heat treatment parameters (i.e. austenitizing temperature and soaking time) with respect to impact toughness. In the first phase, samples were austenitized at different temperatures viz. 760, 800, 840, 880, 920 and 960°C, followed by quenching and tempering at 600°C for 4 hours. In the next phase, samples were subjected to different soaking times (0, 2, 4 and 6 hours) at a fixed austenitizing temperature (980°C), followed by quenching and tempering at 600°C for 4 hours. The samples corresponding to different test conditions were then subjected to instrumented Charpy tests at -40°C and energy absorbed were recorded. Subsequently, microstructure and fracture surface of samples corresponding to different test conditions were observed under scanning electron microscope, and the corresponding grain sizes were measured. In the final stage, austenitizing temperature, soaking time and measured grain sizes were correlated with impact toughness and the fracture morphology and mechanism.

Keywords: heat treatment, grain size, microstructure, retained austenite and impact toughness

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Authors: Sameer Gupta, Prant Gupta

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Context: Fractures in the distal humerus are complex and challenging injuries for orthopaedic surgeons that can be effectively treated with open reduction and internal fixation. Aims: The study analyses clinical outcomes in patients with intra-articular distal humerus fractures (AO type 13 C3 excluded) treated using a different method of fixation ( LCPMS). Subject and Methods: A study was performed, and the author's personal experiences were reported. Thirty patients were treated using an intercondylar screw with lateral column plating and percutaneous medial column screw fixation. Detailed analysis was done for functional outcomes (average arc of motion, union rate, and complications). Statistical Analysis Used: SPSS software version 22.0 was used for statistical analysis. Results: In our study, at the end of 6 months, Overall good to excellent results were achieved in 28 patients out of 30 after analysis on the basis of MEP score. The majority of patients regained full arc of motion, achieved fracture union without any major complications, and were able to perform almost all activities of daily living (which required good elbow joint movements and functions). Conclusion: We concluded that this novel method provides adequate stability and anatomical reconstruction with an early union rate observed at the end of 6 months. Excellent functional outcome was observed in almost all the patients because of less operating time and initiation of early physiotherapy, as most of the patients experienced mild nature of pain post-surgery.

Keywords: intra arricular distal humerus fracture, percutaneous medial screw, lateral column plate, arc of motion

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Authors: Santony Santony, Teguh Rahayu Sartono, Iin Noor Chozin

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Introduction: Pneumonia is acute inflammation on lung parenchyma which is caused by bacteria, virus, fungi, or parasite. In Indonesia, Pneumonia is among the ten inpatient cases. Length of stay is related to the increased morbidity rate, nosocomial infection, and costs. The aim of this study is to assess the effect of pulmonary rehabilitation on the difference in length of stay and the level of Interleukin 6 (IL-6) as an inflammation biomarker for community-acquired pneumonia (CAP) patients in non-intensive rooms. Therefore, pulmonary rehabilitation as adjunctive therapy can be routinely exercised in order to shorten the length of stay, along with the decrease in IL-6 level. Methods: This study was conducted from May to October 2019 at Saiful Anwar General Hospital, Malang. 40 community-acquired pneumonia patients in non-intensive rooms were divided into two groups. 20 patients in the treatment group and 20 patients in the control group, all of them were selected through both inclusion and exclusion criteria. This study used simple consecutive random sampling. In the treatment group, pulmonary rehabilitation performed was composed of breathing exercise, effective coughing technique, clapping (percussion), postural drainage, as well as respiratory muscle training using incentive spirometry device. Pulmonary rehabilitation was conducted twice over five days with a minimum duration of 15 minutes. Blood samples were taken both on the first and the fifth day of the treatment to measure IL-6 level as an inflammation biomarker. Result: For the treatment group, the length of stay was 5.35 days whereas the control group 7.6 days. It can be seen that the treatment group had a shorter length of stay by 2.25 days (P<0,001). The IL-6 level on the first day for the treatment group was 36.27 pg/ml, whereas on the fifth day was 34.36 pg/ml. There was a decrease in IL-6 level on the fifth day of treatment even though it was not statistically significant (P=0.628). IL-6 level on the control group for the first day was 67.76 pg/ml, and after the fifth day, the level decreased to 54.43 pg/ml. There seemed to be a decrease in the IL-6, but it was not statistically significant (P=0.502). On the fifth day, the treatment group showed an average IL-6 level of 34.36 pg/ml. This value was lower than that of the control group which did not receive pulmonary rehabilitation having an IL-6 level of 54.43 pg/ml, even though it was not statistically significant (p=0.221). Conclusion: This study concluded that pulmonary rehabilitation as an adjunctive therapy shortened length of stay by 2.25 days for community-acquired pneumonia patients in a non-intensive room. Both groups experienced a decrease in IL-6 level on the fifth day in comparison with the first day even though it was not statistically significant P>0,05. IL-6 level as an inflammation biomarker decreased on the fifth day of treatment which was in accordance with improvement on pneumonia patients.

Keywords: community-acquired pneumonia, interleukin-6, length of stay, pulmonary rehabilitation

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Authors: Kevlin Govender, Anthony Walker, Glen Bright

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Mass customization is an area of increased importance and the development of rapid tooling applications is pivotal to the success of mass customization. This paper presents a laminated object manufacturing (LOM) process for rapid tooling. The process is termed 3D metal laminate printing and utilizes domestic-grade aluminum foil and epoxy for layered manufacturing. A detailed explanation of the process is presented to produce complex metal laminated composite parts. Aluminum-epoxy composite specimens were manufactured from 0.016mm aluminum and subjected to tensile tests to determine the mechanical properties of the manufactured composite in relation to solid metal specimens. The fracture zone of the specimens was analyzed under scanning electron microscopy (SEM) in order to characterize the fracture mode and study the interfacial bonding of the manufactured laminate specimens.

Keywords: 3D metal laminate printer, aluminum-epoxy composite, laminated object manufacturing, rapid tooling

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Authors: Enerit Saçdanaku, Idriz Haxhiu

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In this study was monitored the population of the European Pond Turtle, Emys orbicularis (Linnaeus, 1758) in the area of Narta Lagoon, Vlora Bay (Albania), from August to October 2014. A total of 54 individuals of E. orbicularis were studied using different methodologies. Curved Carapace Length (CCL), Plastron Length (PL) and Curved Carapace Width (CCW) were measured for each individual of E. orbicularis and were statistically analyzed. All captured turtles were separated in seven different size–classes based on their carapace length (CCL). Each individual of E. orbicularis was marked by notching the carapace (marginal scutes). Form all individuals captured resulted that 37 were females (68.5%), 14 males (25.9%), 3 juveniles (5.5%), while 18 individuals of E. orbicularis were recaptured for the first and some for the second time.

Keywords: Emys orbicularis, female, juvenile, male, population, size–classes

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Authors: Ejazulhaq Rahimi

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The development of techniques evaluating deterioration on concrete structures is vital for structural health monitoring (SHM). One of the main reasons for reinforced concrete structure's deterioration is the corroding of embedded rebars. It is a natural process that begins when the rebar starts to rust. It occurs when the protective layer on the rebar is destroyed. The rebar in concrete is usually protected against corrosion by the high pH of the surrounding cement paste. However, there are chemicals that can destroy the protective layer, making it susceptible to corrosion. It is very destructive for the lifespan and durability of the concrete structure. Corrosion products which are 3 to 6 times voluminous than the rebar stress its surrounding concrete and lead to fracture as cracks even peeling off the cover concrete over the rebar. As is clear that concrete shows limit elastic behavior in its stress strain property, so corrosion product stresses can be detected as strains from the concrete surface. It means that surface strains have a relation with the situation and amount of corrosion products and related concrete fractures inside reinforced concrete. In this paper, a comparative study of surface strains due to corrosion products detected by strain gauges and acoustic emission (AE) testing under periodic accelerated corrosion in the salty environment with 3% NaCl is reported. From the results, three different stages of strains were clearly observed based on the type and rate of strains in each corrosion situation and related fracture types. AE parameters which mostly are related to fracture and their shapes, describe the same phases. It is confirmed that there is a great agreement to the result of each other and describes three phases as generation and expansion of corrosion products and initiation and propagation of corrosion-induced cracks, and surface cracks. In addition, the strain on the concrete surface was rapidly increased before the cracks arrived at the surface of the concrete.

Keywords: acoustic emission, monitoring, rebar corrosion, reinforced concrete, strain

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Authors: M. Bagavandas

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Introduction: South Indian stone sculptures are known for their elegance and history. They are available in large numbers in different monuments situated different parts of South India. These art pieces have been studied using iconography details, but this pioneering study introduces a novel method known as iconometry which is a quantitative study that deals with measurements of different parts of icons to find answers for important unanswered questions. The main aim of this paper is to compare iconometric measurements of the sculptures with canonical proportion to determine whether the sculptors of the past had followed any of the canonical proportions prescribed in the ancient text. If not, this study recovers the proportions used for carving sculptures which is not available to us now. Also, it will be interesting to see how these sculptural proportions of different monuments belonging to different dynasties differ from one another in terms these proportions. Methods and Materials: As Indian sculptures are depicted in different postures, one way of making measurements independent of size, is to decode on a suitable measurement and convert the other measurements as proportions with respect to the chosen measurement. Since in all canonical texts of Indian art, all different measurements are given in terms of face length, it is chosen as the required measurement for standardizing the measurements. In order to compare these facial measurements with measurements prescribed in Indian canons of Iconography, the ten facial measurements like face length, morphological face length, nose length, nose-to-chin length, eye length, lip length, face breadth, nose breadth, eye breadth and lip breadth were standardized using the face length and the number of measurements reduced to nine. Each measurement was divided by the corresponding face length and multiplied by twelve and given in angula unit used in the canonical texts. The reason for multiplying by twelve is that the face length is given as twelve angulas in the canonical texts for all figures. Clustering techniques were used to determine whether the sculptors of the past had followed any of the proportions prescribed in the canonical texts of the past to carve sculptures and also to compare the proportions of sculptures of different monuments. About one hundred twenty-seven stone sculptures from four monuments belonging to the Pallava, the Chola, the Pandya and the Vijayanagar dynasties were taken up for this study. These art pieces belong to a period ranging from the eighth to the sixteenth century A.D. and all of them adorning different monuments situated in different parts of Tamil Nadu State, South India. Anthropometric instruments were used for taking measurements and the author himself had measured all the sample pieces of this study. Result: Statistical analysis of sculptures of different centers of art from different dynasties shows a considerable difference in facial proportions and many of these proportions differ widely from the canonical proportions. The retrieved different facial proportions indicate that the definition of beauty has been changing from period to period and region to region.

Keywords: iconometry, proportions, sculptures, statistics

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Authors: Rotimi Sunday Ajani, Omowumi Femi-Akinlosotu

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Background: The usually paired human kidneys are retroperitoneal urinary organs with some endocrine functions. Standard text books of anatomy ascribe single value to each of the dimension of length, width and thickness. Research questions: These values do not give consideration to racial and genetic variability in human morphology. They may thus be erroneous to students and clinicians working on Nigerians. Objectives: The study aimed at establishing reference values of the kidney length, width and thickness for Nigerians using the cadaveric model. Methodology: The length, width, thickness and weight of sixty kidneys harvested from cadavers of thirty adult Nigerians (Male: Female; 27: 3) were measured. Respective volume was calculated using the ellipsoid formula. Results: The mean length of the kidney was 9.84±0.89 cm (9.63±0.88 {right}; 10.06±0.86 {left}), width- 5.18±0.70 cm (5.21±0.72 {right}; 5.14±0.70 {left}), thickness-3.45±0.56 cm (3.36±0.58 {right}, 3.53±0.55 {left}), weight-125.06±22.34 g (122.36±21.70 {right}; 127.76 ±24.02 {left}) and volume of 95.45± 24.40 cm3 (91.73± 26.84 {right}; 99.17± 25.75 {left}). Discussion: Though the values of the parameters measured were higher for the left kidney (except for the width), they were not statistically significant. The various parameters obtained by this study differ from those of similar studies from other continents. Conclusion: Stating single value for each of the parameter of length, width and thickness of the kidney as currently obtained in textbooks of anatomy may be incomplete information and hence misleading. Thus, there is the need to emphasize racial differences when stating the normal values of kidney dimensions in textbooks of anatomy. Implication for Research and Innovation: The results of the study showed the dimensions of the kidney (length, width and thickness) have interracial vagaries as they were different from those of similar studies and values stated in standard textbooks of human anatomy. Future direction: This is a preliminary report and the study will continue so that more data will be obtained.

Keywords: kidney dimensions, cadaveric estimation, adult nigerians, racial differences

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Authors: Kausar Ali

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There are several ground treatment techniques which may meet the twin objectives of increasing the bearing capacity with simultaneous reduction of settlements, but the use of stone columns is one of the most suited techniques for flexible structures such as embankments, oil storage tanks etc. that can tolerate some settlement and used worldwide. However, when the stone columns in very soft soils are loaded; stone columns undergo excessive settlement due to low lateral confinement provided by the soft soil, leading to the failure of the structure. The poor performance of stone columns under these conditions can be improved by encasing the columns with a suitable geosynthetic. In this study, the effect of reinforcement on bearing capacity of composite soil has been investigated by conducting laboratory model tests on floating and end bearing long stone columns with l/d ratio of 12. The columns were reinforced by providing geosynthetic encasement over varying column length (upper 25%, 50%, 75%, and 100% column length). In this study, a group of columns has been used instead of single column, because in the field, columns used for the purpose always remain in groups. The tests indicate that the encasement over the full column length gives higher failure stress as compared to the encasement over the partial column length for both floating and end bearing long columns. The performance of end-bearing columns was found much better than the floating columns.

Keywords: geosynthetic, ground improvement, soft clay, stone column

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Authors: M. R. Abusrea, Shiyi Jiang, Dingding Chen, Kazuo Arakawa

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Novel wind-lens turbine designs can augment power output. Vacuum-Assisted Resin Transfer Molding (VARTM) is used to form large and complex structures from a Carbon Fiber Reinforced Polymer (CFRP) composite. Typically, wind-lens turbine structures are fabricated in segments, and then bonded to form the final structure. This paper introduces five new adhesive joints, divided into two groups: One is constructed between dry carbon and CFRP fabrics, and the other is constructed with two dry carbon fibers. All joints and CFRP fabrics were made in our laboratory using VARTM manufacturing techniques. Specimens were prepared for tensile testing to measure joint performance. The results showed that the second group of joints achieved a higher tensile strength than the first group. On the other hand, the tensile fracture behavior of the two groups showed the same pattern of crack originating near the joint ends followed by crack propagation until fracture.

Keywords: adhesive joints, CFRP, VARTM, resin transfer molding

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Authors: Alberto Sanchidrián, José A. Parra, Jesús Alonso, Julián Pecharromán, Antonia Pacios, Consuelo Huerta

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Glass is a commonly used material in building; there is not a unique design solution as plates with a different number of layers and interlayers may be used. In most façades, a security glazing have to be used according to its performance in the impact pendulum. The European Standard EN 12600 establishes an impact test procedure for classification under the point of view of the human security, of flat plates with different thickness, using a pendulum of two tires and 50 kg mass that impacts against the plate from different heights. However, this test does not replicate the actual dimensions and border conditions used in building configurations and so the real stress distribution is not determined with this test. The influence of different boundary conditions, as the ones employed in construction sites, is not well taking into account when testing the behaviour of safety glazing and there is not a detailed procedure and criteria to determinate the glass resistance against human impact. To reproduce the actual boundary conditions on site, when needed, the pendulum test is arranged to be used "in situ", with no account for load control, stiffness, and without a standard procedure. Fracture stress of small and large glass plates fit a Weibull distribution with quite a big dispersion so conservative values are adopted for admissible fracture stress under static loads. In fact, test performed for human impact gives a fracture strength two or three times higher, and many times without a total fracture of the glass plate. Newest standards, as for example DIN 18008-4, states for an admissible fracture stress 2.5 times higher than the ones used for static and wing loads. Now two working areas are open: a) to define a standard for the ‘in situ’ test; b) to prepare a laboratory procedure that allows testing with more real stress distribution. To work on both research lines a laboratory that allows to test medium size specimens with different border conditions, has been developed. A special steel frame allows reproducing the stiffness of the glass support substructure, including a rigid condition used as reference. The dynamic behaviour of the glass plate and its support substructure have been characterized with finite elements models updated with modal tests results. In addition, a new portable impact machine is being used to get enough force and direction control during the impact test. Impact based on 100 J is used. To avoid problems with broken glass plates, the test have been done using an aluminium plate of 1000 mm x 700 mm size and 10 mm thickness supported on four sides; three different substructure stiffness conditions are used. A detailed control of the dynamic stiffness and the behaviour of the plate is done with modal tests. Repeatability of the test and reproducibility of results prove that procedure to control both, stiffness of the plate and the impact level, is necessary.

Keywords: glass plates, human impact test, modal test, plate boundary conditions

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