Cause Of Breakage Research Articles

Unveiling Peripherally Inserted Central Catheter Fractures and Related Complications in the Neonatal Intensive Care Unit: A Concise Review.

Peripherally inserted central catheters (PICCs) have become popular over tunneled catheters in neonatal intensive care units (NICUs) due to their ease of use and convenience. Although rare, a PICC fracture can be a severe and potentially fatal complication. This narrative review aims to identify factors predisposing neonates to PICC fracture and related complications, such as catheter jamming, and explore strategies for preventing and detecting this complication. A thorough search of PubMed and Google Scholar was conducted using relevant keywords to identify articles discussing PICC fracture in neonates. The review encompassed English-language literature on PICC fracture in neonates, with additional pertinent publications identified through citation searching. The incidence of PICC fracture in neonates varies from less than 1% to 10%, with a higher risk associated with prolonged catheterization, lower gestational age and lower birth weight, and the use of multi-lumen catheters. PICC fractures can occur during insertion, maintenance, or removal. Factors such as catheter duration, gestational age, birth weight, and catheter type increase the risk of PICC fracture. Excessive syringe pressure, securement failure, and excessive force during removal are contributing factors. Catheter fatigue and thin-walled catheter design are common causes of breakage. Preventive measures include proper training of healthcare providers, regular monitoring, early recognition, and prompt catheter removal upon fracture. Preventing and detecting PICC fractures is crucial for neonatal safety. Vigilance during insertion, maintenance, and removal, along with care to avoid excessive force during removal and high pressure during flushing, can help prevent catheter breakage. More research is required to improve prevention strategies for PICC fractures in neonates.

Causes and Outcome of Central Venous Catheter Repair in Children with Intestinal Failure on Home Parenteral Nutrition.

Children requiring a central venous catheter (CVC) for long-term parenteral nutrition (PN) are at risk of CVC breakage. Modern intestinal failure (IF) management aims to preserve vascular access sites. CVC repair rather than removal is hence attempted for broken catheters. The aim of this study was to describe causes and outcomes of CVC repairs in home PN dependent children. All patients (ages 0-17 years) with CVC dependency enrolled in the IF rehabilitation program of a pediatric referral center were identified, and those who underwent a CVC repair between January 2019 and November 2020 included. Data on associated cause for breakage and incidence of central line-associated bloodstream infections (CLABSIs) post repair were documented retrospectively. Descriptive statistics including medians, percentages, and frequencies were used. Forty children, 15 males (37%) and 25 females (63%), were identified. Fifteen of 40 (37.5%) patients underwent a total of 29 CVC repairs (0.1 repairs per 1000 catheter days); 8 of 15 (53%; 33% females) were <5 years of age. The most common reason for repair was CVC fracture by biting (41%) followed by catheter occlusion with intraluminal PN deposition (13.2%). Repair was successful in 100% cases. Only 1 patient had a confirmed CLABSI post repair (1/29 repairs; 3%) who presented 3 days late after the initial catheter breakage. Catheter salvage was successful with antibiotics. CVC repair in our cohort was very successful and infection rate after repair minimal. CVC repair rather than removal is recommended to preserve central venous access.

An attractive attempt: Facile and direct adhesive of cellulose substrates using inorganic metal salt through partial welding

The development of cellulose-substrate remedies remains a technological challenge owe to their inability to self-heal and excessive dependence on petroleum-based adhesives, which is further hindered by the significant drawbacks of commercially unavailable welding materials and inconvenient manipulation. We herein describe a cellulose-substrate bonding technique achieved through partial dissolution using a low dosage of ZnCl2 aqueous solvent (ZS) and its dissolved cellulose (ZDC) gel as adhesives. This method demonstrates strong joint areas between strips without any failure, while shrinkage in the diffusion area remains the main cause of breakage. This shrinkage phenomenon can be alleviated by using ZDC instead of ZS, due to the water retention of hydrophilic hydroxyls on the macromolecular chains of dissolved cellulose. The well-maintained tensile strength of the ZDC-bonded strip (5.0% lower than the control) indicates that partially dissolved cellulose fills gaps between fibers, providing evidence for a mechanical interlocking adhesive mechanism in strip connections. ZDC gels exhibit favorable adhesive behavior for hand-sheets, art paper, and corrugated board, with welded joints demonstrating robust mechanical performance even after soaking in water for 6 h.

Risk of simultaneous and delayed breakage of total hip replacement ceramic implants in patients with trauma induced periprosthetic fracture and acetabular shell loosening

BackgroundCeramic implant breakage (CIB) in total hip replacement (THR) is a rare incident. A confusion exists between the fragile mechanical behaviour of ceramic materials (brittleness) and fragility in the common sense (easy to break), leading to the misconception that trauma is to blame for these breakages. Trauma has been reported as a cause of breakage by several authors and it is debated whether the burst force can be reached in one single trauma in-vivo. We did a retrospective investigation aiming to determine the risk of CIB associated with a major trauma defined as a periprosthetic femoral fracture (PPFF) or a traumatic loosening of the acetabular shell (TLAS) in ceramic-on-ceramic (CoC) THR. HypothesisThe impact forces responsible of PPFF and TLAS, which are probably the most important impact forces sustained by patients, are not sufficient to induce immediate or delayed CIB. Material and methodsWe conducted a retrospective study on 31 patients (62 ceramic implants, 31 acetabular liners and 31 femoral heads) with a PPFF or TLAS between January 2010 and January 2022. We reviewed the records and X-rays at the time of the major trauma and at the last follow-up. We searched for simultaneous CIB, and those occurring on the non-explanted ceramic implants at last follow up (delayed CIB). These major traumas occurred in 9 men and 22 women. Median age was 75 years old [20–97years old]. There were 28 PPFF and 3 TLAS. Mean time from THR to trauma was 91.2±67months [2.4–240months]. ResultsOn X-rays and after intraoperative confirmation, we do not report any simultaneous CIB on the 62 ceramic implants. Treatment consisted of internal fixation for 20 patients with preservation of both ceramic implants for Vancouver A, B1 and C fractures, 8 stem revisions with preservation of acetabular liner for Vancouver B2 and B3 fractures and 3 acetabular shell revisions to dual mobility and ceramic head change for TLAS. Thus, a total of 48 ceramic implants remained implanted (28 acetabular liners and 20 femoral heads). At last follow-up after the index revision (median=36 months [6–100months]), no patient had a delayed CIB. DiscussionMajor trauma resulting in a PPFF or TLAS in patient withs a CoC THR did not result in simultaneous CIB. The impact forces during these traumas are not sufficient to induce immediate breakage of the ceramic implants. At a median 3years follow-up we found no delayed CIB. Because CIB is a rare event, longer follow up and larger cohort study is needed to determine if a single high impact trauma can initiate and favour the spread of a crack in the ceramic material leading to a breakage. Considering the high mechanical resistance of the ceramic implants and the absence of CIB during or after a major trauma in our study, patients with CoC bearings should not be restricted in their daily activity to prevent CIB. Level of evidenceIV, retrospective cohort study.

Biot’s Variational Method to determine the thermal strain in layered glazings

A critical issue in the structural design of glazed surfaces is the evaluation of the strain consequent to temperature variations due to environmental actions such as solar radiation, which represents one of the main causes of breakage. In the practice, approximate solutions are used, where the temperature profile across the glass thickness is constant or linear, but the consequent thermal stress cannot be adequately estimated from these. On the other hand, sophisticated thermal software is available only for important tasks.Here, we propose a semi-analytical approach, easily implementable in a simple FEM code, to evaluate the time-dependent temperature profile through the thickness of layered glazing, which is based on the variational method proposed by Biot in the Fifties. A prompt evaluation not only of the temperature field, but also of the heat flux, can be obtained. Compared to other numerical approaches, this method rigorously accounts for energy conservation and, since it does not involve temperature gradients in the formulation, it is particularly efficient for problems with steep temperature variations. Temperature profiles that are not necessarily linear can be approximated by Hermite–splines, for a precise evaluation of the thermally-induced stress. Comparisons with a direct numerical solution of the heat-conduction differential equations confirm the accuracy and the effectiveness of the proposed approach.

Specific Features of Using the Linearization Method for the Analysis of Low-Frequency Oscillations of a Towed System

The results of experiments and numerical calculations in the low-frequency range of oscillations of the power and geometric characteristics of a towed system (TS) are presented. The hypotheses used in the linear amplitude-frequency analysis are verified with the use of a discrete model. The limits of applicability of the finite-difference method for numerical TS simulation are determined on the basis of a continuous hyperbolic model that takes into account varying lengthwise tension and finite speed of longitudinal and transverse (configurational) waves. The total error of numerical simulation does not exceed 15–20%. There is a certain delay both in the angle of TS deflection from the vertical and in the maximum horizontal component of the tensile force at its root point. It may be one of the causes of breakage of TS in certain conditions of oscillations and at a certain towing speed, when the tugboat and the TS oscillate in antiphase.

Breakage of Spring Steel During Manufacturing: A Metallurgical Investigation

Spring steel is a name given to a wide range of steels used in the manufacture of springs, prominently in automotive and industrial suspension applications. High carbon of HC82BCr grade steel is drawn in the range of 4.0–3.0 mm as per customer’s requirement for production of spring mainly in automobile components. This spring steel grade is produced from continuous cast billet of size 150 mm × 150 mm and then hot rolled into the size of 5.5 mm diameter wire rod. Quality aspects of these spring are significant as any inherent abnormality in the material could lead to unwanted productivity losses or quality claims or sometimes serious safety issues. In this present study, spring samples broken during coiling stage were collected from plants for understanding their quality aspect and potential causes of breakage during production. Detailed microstructural investigation revealed that the root cause of breakage of the spring is related to the segregation of phosphorous and chromium in the billet which leads to the formation of martensite (brittle and less ductile) in wire rod during rolling process. This volume change due to formation of martensite increases the stress level at the interface of pearlite and martensite. During wire drawing, this increased stress level causes formation of internal crack in subsequent passes causing breakage during spring formation.

Human behavior or taphonomy? On the breakage of Eastern North American Paleoindian endscrapers

Endscrapers, the most abundant tool class at Eastern North American Paleoindian sites, are flaked stone specimens predominately used for scraping hides. They are found broken in high frequencies at these sites, a pattern that has been attributed to use. However, previous experimental and ethnographic research on endscrapers suggests that they are difficult to break. We present a series of replication experiments assessing the amount of force required for endscraper breakage, as well as the amount of force generated during human use. We also analyze which morphometric variable best predicts the breakage force. Our results demonstrate that the force humans can generate is far below the breakage force, which is best predicted by endscraper thickness. Finally, we examine an actual Paleoindian endscraper assemblage, concluding that human use was not the cause for breakage. Taphonomic factors such as plowing, or trampling, are a much better potential explanation for the high breakage frequencies present at Paleoindian sites.

Breakage of electrode grade steel wires during manufacturing: A metallurgical investigation

Wire rods of Electrode Quality (EQ) steel, in sizes ranging between 5.5 mm and 12 mm, are normally produced from continuously cast billets by hot rolling in wire rod mill. These wire rods are subsequently drawn into wires with reduced section in wire drawing plants.The most common grade for EQ steels is ER70S-6 grade which is made of low carbon steel (0.06–0.08 Wt%) with high ‘Mn’ (1.40–1.50 Wt%) and low ‘S' content (0.020 max Wt%). It is a premium mild steel wire formulated to high quality welds and trouble-free performance during applications involving heavy duty, high speed and spray transfer applications all the way to light duty, low speed and short-arc applications. Quality aspects of these drawn wires are of significance as any inherent abnormality in the material could lead to unwanted productivity losses or quality claims. In this present study, wire samples broken during manufacturing were collected from wire drawing plants for understanding their quality aspect and potential causes of breakage while drawing. Detailed microstructural investigation revealed that the root cause of breakage of the wires is related to the welding process deployed by the customer in joining the wire rods. The quality of weldment preparation needs to be paid attention because the two ends of the wires are not fused properly when subjected to welding.

CONVERTING THE AL-31ST ENGINE TO THE CONDITIONS OF MAIN GAS PIPELINES COMPRESSOR STATIONS

Turbojet engines designed for military and civil aviation are intended for flights at level from 9000 to 12000 m, where the air temperature is stable (minus 55 °C), and the air pres- sure corresponds to 150 mm Hg which is five times less than the atmospheric pressure at the surface of the Earth. It is shown that the AL-31ST gas turbine drive has a high sensitivity to the change in the temperature of the air entering the compressor. In the conditions of main gas pipelines compressor stations, in the territories with a continental and sharply continental climate, the air temperature varies greatly (for example, in the conditions of Bashkortostan during 24 hours, air temperature fluctuations can reach 18 °C), as a result of which the operation of the gas turbine engine is unstable, and the blades of high pressure turbine (HPT) experience overload and often break down. In the article, in order to determine the level of rational power loading of GPU-16R «Ufa», in the range of the boundary air temperatures with a deviation of ± 30 °C from the nominal value of 15 °C, at which the blade feather experiences the least load with bending moments, the AL-31ST drive has been recalculated to conditions of Earth-surface application. The analysis of differences between operating and nominal parameters is performed. A flow model of a rotor blade in the relative motion of a gas flow is created and the results of calculation in the form of velocity and pressure fields in the COMSOL Multiphysics 4 program are presented for the air temperature range from minus 15 oС to 45 oС. A signifi-cant difference in the modes is revealed, and the fact of HPT blades overload with bending moments is established, up to 5 % at the boundary temperatures. As a result, the hypothesis of specialists investigating the causes of breakage of the HPT blades was confirmed, that the breakage of the blades is associated with «... related fac-tors», and not «with defects of a metallurgical or casting nature». The HPT blade breaks from the material fatigue caused by periodic bending moments due to fluctuations in the outside air temperature, exceeding the permissible power load up to 5 % in the operating temperature range. Based on the analysis of the AL-31ST drive operation in the range of the outside air tem-perature limits (± 30 oС from the nominal temperature), it is recommended to maintain the operating mode of this drive of no more than 0.95 of the nominal load power.

Novel QTLs Affecting Rice Kernel Fissure Resistance Discovered in the Cultivar ‘Saber’ Augment Those from ‘Cybonnet’

Kernel fissures in rice (Oryza sativa L.) caused by pre‐ or postharvest stresses are the leading cause of breakage among milled rice. Such breakage causes economic losses for producers, millers, and marketers. Five quantitative trait loci (QTLs) for kernel fissure resistance (FR) were identified among a set of 271 recombinant inbred lines derived from ‘Cybonnet’ × ‘Saber’ (CS‐RILs) phenotyped using seven replications of seed harvested from four different environments (year–locations). Use of single‐nucleotide polymorphisms identified additional polymorphism and allowed for more precise mapping of three FR QTLs previously identified using a limited number of simple sequence repeats. Two QTLs were newly discovered in chromosomal regions not previously known to contain genes affecting FR. Saber contributed the FR allele at these newly identified FR QTLs, making them the first FR QTLs not traceable to the ancestral cultivar ‘Cypress’. Fissure resistance among the CS‐RILs proved to be independent from differences for plant height, days to heading, and kernel morphology (i.e., length, width, thickness, and weight). The FR QTLs from Cybonnet and Saber were additive, with stronger levels of FR resulting from pyramiding of FR alleles from both cultivars.

WIRE BREAKAGE DURING WIRE DRAWING DUE TO THE PRESENCE OF SURFACE DEFECTS, INHERITED FROM WIRE ROD

The main causes of wire breakage during drawing are listed, the appearance signs and peculiarities of metallographic structure of destruction are described. The type and cause of the breakage could be identified on basis of this description. The transformation of defects in the drawing process is presented.

Fatigue life evaluation of car front halfshaft

The present paper is the result of the collaboration between the Engineering Department of Messina University and the car company Maserati S.p.A. The aim of this paper is to determine the T-N torsion fatigue curve at R= -1 of the mechanical system "front halfshaft" of an existing car. In particular, experimental fatigue tests were carried out in the laboratories of the Engineering Department of the University of Messina. Torsion fatigue tests of the entire mechanical system were carried out on 15 different front halfshafts. Evaluations of the crack propagation and of failure analysis were made to determine the causes of breakage. In conclusion, the T-N fatigue curve of the mechanical system "front halfshaft" has been obtained.

Cytosine deamination and base excision repair cause R-loop–induced CAG repeat fragility and instability in Saccharomyces cerevisiae

CAG/CTG repeats are structure-forming repetitive DNA sequences, and expansion beyond a threshold of ∼35 CAG repeats is the cause of several human diseases. Expanded CAG repeats are prone to breakage, and repair of the breaks can cause repeat contractions and expansions. In this study, we found that cotranscriptional R-loops formed at a CAG-70 repeat inserted into a yeast chromosome. R-loops were further elevated upon deletion of yeast RNaseH genes and caused repeat fragility. A significant increase in CAG repeat contractions was also observed, consistent with previous human cell studies. Deletion of yeast cytosine deaminase Fcy1 significantly decreased the rate of CAG repeat fragility and contractions in the rnh1Δrnh201Δ background, indicating that Fcy1-mediated deamination is one cause of breakage and contractions in the presence of R-loops. Furthermore, base excision repair (BER) is responsible for causing CAG repeat contractions downstream of Fcy1, but not fragility. The Rad1/XPF and Rad2/XPG nucleases were also important in protecting against contractions, but through BER rather than nucleotide excision repair. Surprisingly, the MutLγ (Mlh1/Mlh3) endonuclease caused R-loop-dependent CAG fragility, defining an alternative function for this complex. These findings provide evidence that breakage at expanded CAG repeats occurs due to R-loop formation and reveal two mechanisms for CAG repeat instability: one mediated by cytosine deamination of DNA engaged in R-loops and the other by MutLγ cleavage. Since disease-causing CAG repeats occur in transcribed regions, our results suggest that R-loop-mediated fragility is a mechanism that could cause DNA damage and repeat-length changes in human cells.

破面形態判別のための破面特徴量抽出に関する研究

The fractography is one of the useful technique for finding the cause of breakage in the engineering parts. However, it is not easy to find an appropriate point on the fracture surface, and also the distinction of fracture surface morphology, such as dimple, river-pattern, striation and so on, needs highly skilled technique. To assist unskilled engineers, there are many studies for quantitative analysis of fracture surface morphology by means of Fractal dimension measurement. It is very interesting that fracture surface possesses fractal structure, but it is still difficult to distinguish the fracture surface morphology by using fractal dimensions measurement. On the other hand, Recurrence plots introduced by Eckmann et al. provide a way to visualize the periodic nature of events such as fracture surface’s characteristic feature. Therefore, by applying the image recognition technique to Recurrence plots obtained from fracture surface, it is expected to see the fractographical feature extraction for distinguishing fracture surface morphology.

Kirschner Wire Breakage during Removal Requiring Retrieval.

Kirschner wires (K-wires) are widely used for fixation of fractures and dislocations in the hand as they are readily available, reliable, and cost-effective. Complication rates of up to 18% have been reported. However, K-wire breakage during removal is rare. We present one such case illustrating a simple technique for retrieval. A 35-year-old male presented with a distal phalanx fracture of his right middle finger. This open fracture was treated with K-wire fixation. Postoperatively, he developed a pin site infection with associated finger swelling. The K-wire broke during removal with the proximal piece completely retained in his middle phalanx. To minimise risk of osteomyelitis, the K-wire was removed with a novel surgical technique. He had full return of hand function. Intraoperative K-wire breakage has a reported rate of 0.1%. In our case, there was no obvious cause of breakage and the patient denied postoperative trauma. On the other hand, pin site infections are much more common with reported rates of up to 7% in the hand or wrist. K-wire fixation is a simple method for bony stabilisation but can be a demanding procedure with complications often overlooked. It is important to be aware of the potential sequelae.

Cytokinesis breaks dicentric chromosomes preferentially at pericentromeric regions and telomere fusions.

Dicentric chromosomes are unstable products of erroneous DNA repair events that can lead to further genome rearrangements and extended gene copy number variations. During mitosis, they form anaphase bridges, resulting in chromosome breakage by an unknown mechanism. In budding yeast, dicentrics generated by telomere fusion break at the fusion, a process that restores the parental karyotype and protects cells from rare accidental telomere fusion. Here, we observed that dicentrics lacking telomere fusion preferentially break within a 25- to 30-kb-long region next to the centromeres. In all cases, dicentric breakage requires anaphase exit, ruling out stretching by the elongated mitotic spindle as the cause of breakage. Instead, breakage requires cytokinesis. In the presence of dicentrics, the cytokinetic septa pinch the nucleus, suggesting that dicentrics are severed after actomyosin ring contraction. At this time, centromeres and spindle pole bodies relocate to the bud neck, explaining how cytokinesis can sever dicentrics near centromeres.

Breakage Patterns on Fishtail Projectile Points: Experimental and Archaeological Cases

Fishtail projectile points, also known as Fell 1, are dated between 11,000 and 9,500 14C yr B.P. in South and Central America and have been traditionally considered diagnostic of the early peopling of the continent. In this paper, experimental observations of impact breakage patterns on fishtail projectile point replicas are compared with archaeological points from the Cerro El Sombrero Cima site, in the Argentinian pampas, which exhibit a high breakage ratio and suggest that impact was a major cause of breakage in the assemblage. The position of these fractures is also briefly compared to patterns described by J. Bird (1969) for fishtail projectile points from Ecuador and Southern Chile.

Nodular Inhomogeneous Graphitization – Determining Factor of Fatigue Failure

The paper investigates the causes that led to the premature failure of a crankshaft (approximately 200 hours) from an engine used in equipment that worked on a construction site for concrete pumping. Microscopic analysis (optic and electronic), chemical and macroscopic investigations were conducted in order to find the causes of breakage of the crankshaft.

Occult risk of broken instruments for endoscopy-assisted surgery.

The influence of broken sophisticated surgical instruments on the safety of surgery has yet to be determined, in spite of an assumption that breakage of surgical instruments is not associated with critical incidents. The purpose of the present study was to delineate the risk from breakage of surgical instruments used in surgery assisted by endoscopy. A retrospective analysis was conducted to determine the frequency of breakage of instruments used in 39,817 operations from 2007 to 2011. Data of breakage were collected using incident/near-incident reports and the request forms for repair of broken instruments. During the study period, 441 instruments were reported to be broken intraoperatively, and 7,541 were found to be broken on inspection. The incidence of breakage adjusted by the number of operations and the number of uses suggested that instruments for endoscopy-assisted surgery are broken more frequently intraoperatively than are any other type of instruments (visceral surgery: 0.039 versus 0.017, P = 0.0002, RR = 2.318; obstetrics/gynecology: 0.023 versus 0.0067, P < 0.0001, RR = 3.461; thoracic surgery: 0.019 versus 0.004, P = 0.0772, RR = 5.212). Inappropriate use and wearing out were two major possible causes of breakage of instruments. The predominant adverse events were suggested to be attributable to parts falling off broken instruments because of inappropriate use. Our results demonstrated that surgery assisted by endoscopy has its own occult risk, which has not been previously highlighted. Minimally invasive surgery is not necessarily safe with respect to breakage of surgical instruments. Our data provide substantial evidence for higher risk of instrument breakage in endoscopy-assisted surgery, as well as its possible detrimental effect on patient safety.