Position Of Break Research Articles

On the violation of the zeroth law of turbulence in space plasmas

The zeroth law of turbulence states that, for fixed energy input into large-scale motions, the statistical steady state of a turbulent system is independent of microphysical dissipation properties. This behaviour, which is fundamental to nearly all fluid-like systems from industrial processes to galaxies, occurs because nonlinear processes generate smaller and smaller scales in the flow, until the dissipation – no matter how small – can thermalise the energy input. Using direct numerical simulations and theoretical arguments, we show that in strongly magnetised plasma turbulence such as that recently observed by the Parker Solar Probe spacecraft, the zeroth law is routinely violated. Namely, when such turbulence is ‘imbalanced’ – when the large-scale energy input is dominated by Alfvénic perturbations propagating in one direction (the most common situation in space plasmas) – nonlinear conservation laws imply the existence of a ‘barrier’ at scales near the ion gyroradius. This causes energy to build up over time at large scales. The resulting magnetic-energy spectra bear a strong resemblance to those observedin situ, exhibiting a sharp, steep kinetic transition range above and around the ion-Larmor scale, with flattening at yet smaller scales. The effect thus offers a possible solution to the decade-long puzzle of the position and variability of ion-kinetic spectral breaks in plasma turbulence. The existence of the ‘barrier’ also suggests that, how a plasma is forced at large scales (the imbalance) may have a crucial influence on thermodynamic properties such as the ion-to-electron heating ratio.

Computer ergonomics related health problems of Library staff: a case study at the University of Colombo

This paper discusses computer ergonomics related health problems caused by prolonged use of computers in the library staff of the University of Colombo. The heterogeneous population, 60 in total consisted of academic staff, administrative officers and paraprofessional staff including Senior Staff Assistants, Staff Assistants, Management Assistants and Library Information Assistants. A stratified random sampling technique was used to draw the sample (52). A questionnaire was administered to collect data. Data were analysed with descriptive statistics and correlation test using SPSS version 23. It revealed that neck pain was the major (63.8%) musculoskeletal discomfort experienced by the respondents after prolonged period of computer usage followed by shoulder pain (59.6%) and pain in the wrist (53.2%). Pain in the eye (76.6%) was the most persistent visual discomfort experienced by the respondents followed by headaches (72.3%). Major stress-related problem was sleepiness (51.1%) while loss of concentration was identified as the prominent discomfort related to fatigue (27.7%). Prevalence of musculoskeletal discomforts such as pain in the neck and lower arm showed a positive correlation with the height of computer table (r = 0.447, P=0.002 and r = 0.403, P=0.005 respectively), while shoulder pain indicated a weak negative correlation with wrist support (r = -0.317, P=0.03). Data on prevalence of lower arm pain depicted a weak positive correlation with height and distance of the keyboard (r = 0.384, P=0.008) and computer desk height (r = 0.403, P=0.005). As for visual discomfort symptoms developing double vision had a weak positive correlation with glare (r =0.315, P=0.031) and a weak negative correlation with lighting in the workstation (r=- 0.291, P=0.046). Headaches due to extended use of computers showed a significant relationship with view distance (P=0.003) and task breaking (P=0.033). To avoid visual discomforts ergonomic requirement at the computer workstation should be proper lighting, anti-glare filters, and ergonomic positioning of computer monitor and regular work breaks. To reduce health problems, library management should organize workstation ergonomic training sessions to gain knowledge and skills required to optimize the workstation configuration, and provide ergonomically safe working equipment.

Current and New Next-Generation Sequencing Approaches to Study Mitochondrial DNA

Mitochondria harbor multiple copies of a maternally inherited nonnuclear genome. Point mutations, deletions, or depletion of the mitochondrial DNA (mtDNA) are associated with various human diseases. mtDNA defects are currently studied using Sanger sequencing, Southern blot, and long and quantitative PCR. However, these technologies are expensive and are limited in speed, throughput, and sensitivity. Recently, next-generation sequencing (NGS) has been used to study mtDNA defects; however, its potential applications still need to be fully validated. We analyzed mtDNA from 16 control samples and 33 affected samples, which were previously investigated by traditional techniques. Different NGS approaches were tested, using classic library preparation based on PCR amplifications and an innovative PCR-free protocol, defining their suitability and utility for: i) generating full accurate mtDNA sequence, ii) assessing heteroplasmy for single point mutations with high accuracy, and iii) detecting break positions and heteroplasmy of single large deletions. This study confirmed that PCR-based library preparations are appropriate for the first two points and showed that a new PCR-free method gave the best results for the third aim. This study tested different approaches and describes an innovative PCR-free protocol, suitable for detection and heteroplasmy quantification of mtDNA single large deletions. NGS may become the method of choice for genetic analysis on mtDNA.

Typing FGFR2 translocation determines the response to targeted therapy of intrahepatic cholangiocarcinomas

Chromosomal translocations involving fibroblast growth factor receptor 2 (FGFR2) gene at the breakpoints are common genetic lesions in intrahepatic cholangiocarcinoma (ICC) and the resultant fusion protein products have emerged as promising druggable targets. However, predicting the sensitivity of FGFR2 fusions to FGFR kinase inhibitors is crucial to the prognosis of the ICC-targeted therapy. Here, we report identification of nine FGFR2 translocations out of 173 (5.2%) ICC tumors. Although clinicopathologically these FGFR2 translocation bearing ICC tumors are indistinguishable from the rest of the cohort, they are invariably of the mass-forming type originated from the small bile duct. We show that the protein products of FGFR2 fusions can be classified into three subtypes based on the breaking positions of the fusion partners: the classical fusions that retain the tyrosine kinase (TK) and the Immunoglobulin (Ig)-like domains (n = 6); the sub-classical fusions that retain only the TK domain without the Ig-like domain (n = 1); and the non-classical fusions that lack both the TK and Ig-like domains (n = 2). We demonstrate that cholangiocarcinoma cells engineered to express the classical and sub-classical fusions show sensitivity to FGFR-specific kinase inhibitors as evident by the suppression of MAPK/ERK and AKT/PI3K activities following the inhibitor treatment. Furthermore, the kinase-deficient mutant of the sub-classical fusion also lost its sensitivity to the FGFR-specific inhibitors. Taken together, our study suggests that it is essential to determine the breakpoint and type of FGFR2 fusions in the small bile duct subtype of ICC for the targeted treatment.

Preventing nickel-titanium rotary instrument from breakage by continuous irrigation with different fluids during root canal preparation.

To study the effect of continuous irrigation of rotating nickel-titanium instrument with several common clinical fluids on the diameter, breaking length and breaking position of nickel-titanium instrument, so as to provide some reference and theoretical basis for clinical operation and instrument improvement.A standardized curved root canal model was established, and ProTaper Universal (PTU) F1 instrument was selected for root canal preparation. The nickel-titanium F1 instrument was flushed with distilled water, 0.9% NaCl, 0.2% chlorhexidine, 1% sodium hypochlorite and 5% sodium hypochlorite, and the diameter, length and position of the instrument before and after breakage were recorded.Only 5% sodium hypochlorite influenced the diameter of 6 mm marker points under different irrigation conditions (P < .05). There was no statistical difference in the length of broken instruments among all the groups, and torsional deformation mainly occurred at the end of broken instruments. The broken positions of instruments in all the groups were located at the bending segment of the root canal. The breaking frequency of the 5% sodium hypochlorite group was the highest in the area 3–5.5 mm away from apical foramen, while the other 4 groups had the highest breaking frequency in the area 0 to 1.5 mm away from apical foramen.External irrigation with different fluids did not influence the breaking length of instruments. The closer to the apical foramen was, the higher the breaking frequency of instruments was. However, only 5% sodium hypochlorite can affect the diameter of rotary nickel-titanium instruments, and may lead to early breakage of the instrument, indicating that the use of disinfectants, except 5% sodium hypochlorite, cannot reduce breakage resistance of nickel-titanium instrument compared with distilled water flushing. Furthermore, 5% hypochlorite could not be recommended for irrigation in clinical practice.

Tunable Fano Resonance and Enhanced Sensing in Terahertz Metamaterial

Fano resonances in metamaterial are important due to their low-loss subradiant behavior that allows excitation of high quality (Q) factor resonances extending from the microwave to the optical bands. Fano resonances have recently showed their great potential in the areas of modulation, filtering, and sensing for their extremely narrow linewidths. However, the Fano resonances in a metamaterial system arise from the interaction of all that form the structure, limiting the tunability of the resonances. Besides, sensing trace analytes using Fano resonances are still challenging. In the present work, we demonstrate the excitation of Fano resonances in metamaterial consisting of a period array of two concentric double-split-ring resonators with symmetry breaking (position asymmetry and gaps asymmetry). The tunability and sensing of Fano resonances are both studied in detail. Introducing position asymmetry in the metamaterial leads to one Fano resonance located at 0.50 THz, while introducing gaps asymmetry results in two Fano resonances located at 0.35 THz and 0.50 THz. The transmittance, position, and linewidth of the three Fano resonances can be easily tuned by varying the asymmetry deviations. The Q factor and figure of merit (FoM) of Fano resonances with different asymmetry deviations are calculated for performance optimization. The Fano resonances having the highest FoM are used for the sensing of analytes at different refractive indices, and the Fano resonance performing the best in refractive index sensing is further applied to detect the analyte thickness. The results demonstrate that the tunable Fano resonances show tremendous potential in sensing applications, offering an approach to engineering highly efficient modulators and sensors.

A Novel Mining Method for Longwall Panel Face Passing through Parallel Abandoned Roadways

Mining pressure behavior in the process of longwall panel face passing through the parallel abandoned roadways (PARs) is different from the ordinary longwall panel face. It is easy to induce the accident of roof falling, coal wall spalling, and crush accident of shield. In order to reduce the occurrence of mine pressure accidents and ensure safe mining, a new mining method named “swing‐inclined” mining method was proposed and was employed in the E13103 of Cuijiazhai coal mine. Based on the process of the longwall panel face passing through the PARs, a long‐span and multisupport mass‐structure model of the roof was established. The maximum support capacity of shield was calculated combined with stability relation between “roof‐shield‐PAR‐‘similar pillar (SP)’‐coal wall.” It provided the basis for determining the reasonable support capacity of shield. Moreover, the sensitivity analysis of influenced factors to the maximum support capacity of shield was carried out by using Matlab software. The sensitivity analysis results indicated that different factors had a different effect on the support capacity of shield. And, the process of passing through the PARs can be divided into 3 stages, depending on the relation between support capacity of shield and width of SP. In different stages, the change degree of support capacity of shield was different. The support capacity of shield is mainly influenced by the hanging distance of the main roof and the horizontal distance between the support point of the coal wall and the breaking position of the main roof. By on‐site measurement, the sensitivity analysis results were verified.

ASSESSING THE EFFECT OF EARTHQUAKE-INDUCED UPLIFT AND ENGINEERING WORKS ON A SURF BREAK OF NATIONAL SIGNIFICANCE

In November 2016 a Mw7.8 earthquake struck the northeast coast of the New Zealand South Island triggering numerous large landslips which severed key infrastructure and caused parts of the coastline to be uplifted by up to 3 m. This affected a notable surf break at Mangamaunu, north of Kaikoura. The uplift of the seabed at this location caused changes in the wave breaking characteristics and, at the same time, infrastructure recovery efforts proposed construction of engineering works along the site shoreline. The potential impacts of these works on the surf break caused significant local, national and international concern. An extensive study was initiated to better understand the characteristics of the surf break, the effects of the earthquake-induced seabed uplift and the potential effects of the engineering works. This included collection of topographic and bathymetric data using a combination of LiDAR, multibeam and an innovative UAV-based collection method within the surf zone. This provided a seamless terrain model which could be adjusted to pre-earthquake levels based on observed uplift rates. Two fixed camera stations were established with ground control information to collect data on wave breaking position and GPS-watches were deployed and utilized by the local surfing community to collect similar data. Image processing algorithms were developed to extract wave breaking on a wave-by-wave basis and aggregate to obtain breaking exceedance contours, an improvement from threshold analysis on time-averaged imagery. Both physical and numerical modelling was undertaken to better understand the effect of the earthquake and of the proposed works on wave characteristics, particularly wave reflection. The non-hydrostatic wave-flow model SWASH (Smit et al., 2013) was used to evaluate changes in the breaking position, the incident and reflected wave energy gradients, and surf zone hydrodynamics during a range of typical and optimal surfing conditions for present day and future water levels. An innovative wave breaking position post-processing routine was developed to allow assessment of the impact of reflected waves on the surfability of incoming wave forms on a wave-by-wave basis. Results found that the breaking mechanics of the surf break is controlled not only by nearshore bathymetry around break point but also offshore features which cause focusing of wave energy. The uplift has caused significant changes to the breaking characteristics, with increased wave focusing, breaking and dissipation. The proposed engineering works were found to potentially cause increased wave reflection at the outer part of the surf break during high water levels, however the spatial and temporal characteristics of this reflection mean that direct impacts on surfability are likely to be limited.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/u6nLAp-gQxw

Outcomes of Rhegmatogenous Retinal Detachment

Purpose: To study demographic characteristics and treatment outcomes of Rhegmatogenous retinal detachment in a private Vitreo-retinal setup of Lahore.&#x0D; Study Design: Cross sectional Observational study.&#x0D; Place and Duration of Study: Private Vitreo-retinal setup, from March 2017 to April 2019.&#x0D; Methods: Total 102 patients with Rhegmatogenous retinal detachment (RRD) were included. Patients with retinal detachment other than RRD were excluded. Detailed history and ocular examination was performed. Type of break, procedure adopted for RRD repair and type of endo-tamponade were also recorded. These patients had either 23 G pars plana vitrectomy (PPV) or scleral buckling (SB) procedures or combined sclera buckling with PPV. Patients were followed-up for six months.&#x0D; Results: Out of 102 total RRD cases, 63.70% were males and 36.30%were females. Mean age was 47.44 ± 18.44. Macula was on in 48% and off in 52%. Phakic patients were 46.50%, pseudophakic 48.50% and 5.10% were aphakic. Position of break in RRD was superotemporal in 39.2%, inferotemporal in 30.4% and inferonasal in 2.9%. Total RD was observed in 27.5% patients. One or more breaks were identified in 82.4% patients and giant tear in 4.9%. Three ports 23 G PPV was done in 64.7%, PPV with IOL in 18.6%, scleral buckling in 10.8% and combined PPV + SB in 5.9% patients. The anatomical success rate was observed in 96.07%, 3.9% needed second surgery to get anatomical success in six months follow-up.&#x0D; Conclusion: Anatomical success rates in retinal attachment surgeries in experienced hands is comparable with more developed retinal centers of the world.&#x0D; Key Words: Rhegmatogenous retinal detachment, Pars plana vitrectomy, Scleral buckling, Silicon oil.

IDENTIFICATION OF FEATURES IN PREDICTING PROMINENT MALAY WORDS USING DECISION TREE

Predicting word prominence is a major topic in the field of speech synthesis where predicting prominent words is necessary to produce a natural-sounding speech synthesis. In our previous work, marking prominent words in a speech corpus is required to select the most suitable unit for speech synthesis; however, given that marking is performed manually, building a large speech corpus will be expensive in terms of labor and time-consuming. Thus, predicting prominent words automatically for which features represent an important aspect is required. This study presents an experimental work on identifying features (including part-of-speech (POS) sequence, phrasal break, and word position) in predicting prominent Malay words using decision tree and WEKA feature selection correlation method. Results show that using the decision tree for predicting prominent words (Precision = 85.0%, Recall = 84.2%, and F-measure = 83.5%) is optimal when the phrasal break is omitted as a feature. In addition, the results (Precision = 66.40%, Recall = 67.2%, and F-measure = 66.60%) are poorest when the POS sequence is excluded from the features. Therefore, this study concludes that phrasal break is a weak (noisy) feature, whereas POS sequence is an important feature in predicting prominent Malay words.

Finding the hole in a wall

In this paper we model a graphene nano-ribbon structure by analysing an infinite 3-regular hexagonal grid which is transformed to a rectangular coordinate system or “wall”. Our goal is to solve the inverse problem of identifying the position of a single vacancy break using the lengths of the closed paths along the edges of the underlying graph. We provide an algorithm to determine the exact position of the defect by using data from at most three reference points.

Physical parameters of active galactic nuclei derived from properties of the jet geometry transition region

ABSTRACT We use the observed jet boundary transition from parabolic to conical shape, which was previously discovered to be a possible common property in active galactic nuclei, to estimate various parameters for black holes, jets and the ambient medium. We previously explained the geometry transition as a consequence of a change in the jet properties: a transition from a magnetically dominated to an equipartition regime. This interpretation allows us to estimate the black hole spin, the black hole mass and the ambient pressure amplitude, using the observed jet shape break position and the jet width at the transition point, for 11 active galactic nuclei. The black hole spin values obtained using our method are consistent with the lower estimates for sources with redshift z &amp;lt; 2 from spin evolution modelling. We find that the method of black hole mass determination based on the relationship between the broad-line region size and its luminosity may underestimate the masses of sources with large jet viewing angles. We propose a new method for the determination of the black hole mass, obtaining masses in the interval 108–1010 M⊙. The range of values of the ambient pressure amplitude points to the uniform medium conditions for the sources in our sample, with a tentative indication of higher pressure around Fanaroff–Riley II sources.

The effect of positions of line breaks on eye-movement during reading sentences

The effect of positions of line breaks on eye-movement during reading sentences

Study on the Breakdown Mechanism of Water Film on Corrugated Plate Wall Under the Horizontal Shear of Airflow: A Short Communication

The corrugated plate dryer is an important steam-water separation equipment in the steam generator in the secondary loop of nuclear power plants. Therefore, it is very important to understand the process and mechanism of liquid film rupture on the wall surface of the corrugated plate dryer. In this paper, for the first time, the process of rupture of the liquid film on the surface of the corrugated plate is studied. The mechanism of liquid film rupture on the wall surface of vertical corrugated plate was studied experimentally. The high-speed camera was used to collect the image of the broken liquid film, and the experimental research on the broken position, the broken process and the broken shape of the liquid film was carried out. The results show that the rupture of the liquid film on the wall surface of the corrugated plate under the horizontal shear of air flow mostly occurs at the upper middle position of the main flow of the liquid film. And the rupture position moves up with the increase of the Reynolds number of the liquid film. Liquid film rupture needs to go through the process of stable flow, single strip-shaped liquid film detachment, two strip-shaped liquid film formation, and finally chaotic disordered rupture. The angle between the two strip-shaped liquid films is positively related to the Reynolds number of the liquid film.

PARSING AMBIGUOUS RELATIVE CLAUSES IN L2 ENGLISH

AbstractWe investigate effects of prosodic cues on interpretation of ambiguous sentences containing relative clauses (RCs) in English by Spanish-speaking learners. English and Spanish differ in default preference for RC attachment: English has a weak low attachment (LA) preference (RC modifies NP2); Spanish has a stronger high attachment (HA) preference (RC modifies NP1). We conducted an interpretation task with auditorily presented stimuli to examine whether prosodic cues determine attachment. Target items were manipulated for position of break and length of RC, NP1, and NP2. For both groups, break and length are significant. For the learners, proficiency interacts with break suggesting L1 transfer: lower proficiency learners choose HA more when break points to LA; higher proficiency learners choose HA more when break points to HA. Lower proficiency learners are more likely to choose LA overall, suggesting a recency effect. Our results confirm the importance of using aural stimuli when testing interpretation of ambiguous sentences.

The Research of the Rolling Speed Influence on the Mechanism of Strip Breaks in the Steel Rolling Process.

This paper evaluates the results of research aimed at changing the rolling speed and the effect of foreign particles in the steel strip, as well as the forces in the rolling process. It also compares the correlation of lab results, theoretical expectations and real-life observations. It supplements the already existing practices aimed at strip-break elimination that were developed and implemented worldwide. Records from a five-stand tandem mill were used for the data analysis. The historical databases developed based on incidents (strip breaks) since 2013 were used; the detailed position of each strip break was documented, along with defects found at the portions of steel strips that broke or the information that no defect was found. The paper contains an evaluation of metallographic analyses of the samples of the strip breaks.

The interaction between the transient cavitating flow and hydrodynamic performance around a pitching hydrofoil

The interaction between the unsteady cavitating flow and hydrodynamic performance around a pitching Clark-Y hydrofoil is investigated experimentally and numerically. The experiments were conducted in the looped cavitation tunnel, and the cavitation patterns are documented by two high-speed digital cameras, and the moment of hydrofoil is measured by the moment sensor. The pitching hydrofoil is controlled from α+ = 10° to α+ = 15° firstly, and goes back to α− = 5° from α+ = 15°, then goes back to α+ = 10° from α− = 5° at Re = 4.4∗105. The upstream velocity U∞ and the cavitation number σ is fixed at 6.3 m/s and 1.38, respectively. And the pitching rate is α˙=40∘/s,α˙∗=0.086. The numerical investigations were performed by solving the incompressible UNRANS equations via the commercial code CFX using the Merkle cavitation model, the coupled k-ω SST turbulence model and γ-Reθ transition model. The predicted cavity patterns and moment coefficients agree well with the experimental results. The results showed there are two distinct cavitation patterns (Multi-scale cloud cavitation and Traveling sheet cavitation). For the Multi-scale cloud cavitation phase (α+ = 10°-α- = 10°), the re-entrant flow is the main factor on the stability of cavitating flow structures, which is responsible for different shedding patterns. According to the breaking position and re-entrant flow thickness, this stage is divided into three different patterns of the cavity development and shedding. For the Traveling sheet cavitation phase (α− = 10°-α+ = 10°), the shedding of cavity mainly results from the interaction of the re-entrant flow and the fluctuation of the gas liquid interface, thus leading to the irregular breaking points. The cavitating flow structure of different phases were further investigated using the LESs, which will be help to identify the dynamic behavior of flow structures effectively.

Chromosome-nuclear envelope tethering - a process that orchestrates homologue pairing during plant meiosis?

ABSTRACTDuring prophase I of meiosis, homologous chromosomes pair, synapse and exchange their genetic material through reciprocal homologous recombination, a phenomenon essential for faithful chromosome segregation. Partial sequence identity between non-homologous and heterologous chromosomes can also lead to recombination (ectopic recombination), a highly deleterious process that rapidly compromises genome integrity. To avoid ectopic exchange, homology recognition must be extended from the narrow position of a crossover-competent double-strand break to the entire chromosome. Here, we review advances on chromosome behaviour during meiotic prophase I in higher plants, by integrating centromere- and telomere dynamics driven by cytoskeletal motor proteins, into the processes of homologue pairing, synapsis and recombination. Centromere–centromere associations and the gathering of telomeres at the onset of meiosis at opposite nuclear poles create a spatially organised and restricted nuclear state in which homologous DNA interactions are favoured but ectopic interactions also occur. The release and dispersion of centromeres from the nuclear periphery increases the motility of chromosome arms, allowing meiosis-specific movements that disrupt ectopic interactions. Subsequent expansion of interstitial synapsis from numerous homologous interactions further corrects ectopic interactions. Movement and organisation of chromosomes, thus, evolved to facilitate the pairing process, and can be modulated by distinct stages of chromatin associations at the nuclear envelope and their collective release.

Nucleosomes effectively shield DNA from radiation damage in living cells.

Eukaryotic DNA is organized in nucleosomes, which package DNA and regulate its accessibility to transcription, replication, recombination and repair. Here, we show that in living cells nucleosomes protect DNA from high-energy radiation and reactive oxygen species. We combined sequence-based methods (ATAC-seq and BLISS) to determine the position of both nucleosomes and double strand breaks (DSBs) in the genome of nucleosome-rich malignant mesothelioma cells, and of the same cells partially depleted of nucleosomes. The results were replicated in the human MCF-7 breast carcinoma cell line. We found that, for each genomic sequence, the probability of DSB formation is directly proportional to the fraction of time it is nucleosome-free; DSBs accumulate distal from the nucleosome dyad axis. Nucleosome free regions and promoters of actively transcribed genes are more sensitive to DSB formation, and consequently to mutation. We argue that this may be true for a variety of chemical and physical DNA damaging agents.

Cavitating flow structures and corresponding hydrodynamics of a transient pitching hydrofoil in different cavitation regimes

The present paper applied experimental and numerical methods to investigate the cavitating flow structures and corresponding hydrodynamics for a transient pitching Clark-Y hydrofoil. The aims are to (1) improve the understanding of the interplay between the transient cavitating flow structures, motion of the hydrofoil, and hydrodynamic performance, (2) quantify the influence of cavitation on the hydrodynamic load coefficients and flow structures, and (3) analyze the evolution of cavitating flow during different cavitation regime. The pitching motion trajectory is a triangular wave with mean incidence of α0=10° and amplitude of Δα = 5° at a frequency of 2 Hz. The upstream velocity U∞ is fixed at 6.3 m/s, which is corresponding to Re=4.4 × 105. The cavitation patterns for different cavitation numbers are mainly documented by the high-speed photography, and the dynamic characteristics of the hydrofoil are measured by the torque sensor. The numerical investigations were performed by solving the incompressible URANS equations using the mass-transfer cavitation model, the coupled k-ω SST turbulence model and γ-Reθ transition model. The predicted cavity patterns and moment coefficients agree well with the experimental results. Four typical regimes, including sub cavitation, inception cavitation, sheet cavitation and cloud cavitation, are observed. Compared to the sub cavitation case, the hydrodynamic coefficients and flow structures are significantly affected by the incipient cavity. Results show that the leading edge (LE) cavity promotes the formation of the counterclockwise tailing edge vortex (TEV), thus leading to decline of the lift. Moreover, the LE cavity also limits the formation of the clockwise second vortex (SV), which weakens the fluctuation of the hydrodynamic load. For the sheet cavitation case, three cavitating flow patterns(Pattern A/B/C) are observed in the hydrodynamic fluctuation stage, which is corresponding to different characteristic frequency. For the cloud cavitation case, the hydrodynamic curves present four distinct stages. According to the cavity breaking position and characteristic frequency, four different patterns(Pattern I/II/III/IV) of the cavity development and shedding are observed and analyzed.