The increasing penetration of inverter-based resources (IBRs) is changing grid dynamics and challenging grid planning, operation, and protection. Particularly, the increasing integration of IBRs may drive the power grid towards weak grid conditions, where potential dynamic stability issues may become significant. Recently, it was reported that the unintended loss of solar generation occurred in Southern California over a large geographic area. One of the major reasons for this generation loss is the tripping of solar generators due to the overvoltage in a less than one cycle time frame (i.e., sub-cycle overvoltage) experienced by solar photovoltaic (PV) inverters, especially when solar PV inverters enter the momentary cessation operation mode in response to abnormal grid disturbances. In this paper, the impact of grid strength on sub-cycle dynamics resulting from momentary cessation is investigated in a power system with distributed solar PV integration. In this investigation, distributed solar PVs are modeled with detailed grid-following inverter models considering inverter switching dynamics and momentary cessation function. It is found that undesired sub-cycle overvoltage has a positive relation to grid strength at points of integration (POIs) of solar PVs. At the weak POIs, server sub-cycle overvoltage occurs not only when momentary cessation starts to cease energy injection but also when momentary cessation restarts to inject energy into the system during the restoration process. Furhtermore, the interaction between solar PVs making POIs weak exacerbates the severity of the sub-cycle overvoltage at the POIs. Thus, in the power system with high penetration of solar PVs, it is important to improve grid strength in power system planning and quickly recover grid strength in power system operation following disturbances.
When it comes to providing support to children with disabilities, this role is primarily taken over by the family, and above all by the parents. The research was conducted to determine which protective factors of mental health for parents of children with disabilities facilitate their parenting role. The sample consisted of 17 participants, parents of children with various disabilities who filled out an online questionnaire designed for the needs of the research. The questionnaire was intended to assess the protective factors of the mental health of parents of children with disabilities. The results showed that parents experience moderate to high levels of stress when it comes to their parental role, while they emphasize child care as the main source of stress related to the parental role. They point out social support as one of the leading sources of support, much more often relying on informal sources (family members, friends, neighbors). In addition to social support, significant protective factors include faith in God and personality traits such as patience (calmness), perseverance, strength (resilience), optimism, and hope. Destigmatization also stands out as a significant protective factor, ie the parental role is facilitated by the complete acceptance of the child by the environment. Based on the findings, guidelines and recommendations can be formulated for planning and creating a program to provide support to parents of children with disabilities. In this context, various psychosocial support programs aimed at strengthening parental competencies and protective factors that play an important role in preserving the mental health of parents of children with disabilities would be significant.
This paper presents two spheres of public engagement of women in the contemporary society of Bosnia and Herzegovina (BiH): politics and the academic community. An insight into the first sphere, the political one, provides an introductory, succinct overview of the development of societal roles and positions of women during the period of Jugloslawia (1945-1992). Afterward, it focuses on the current position of women in another public sphere, the academic community. The applied method was a test (questionnaire). The first challenge was to determine the exact number of women engaged in the teaching process at the chosen public university in BiH (University of Zenica) since it was not possible to obtain data through the official internet websites or from the relevant published documents. According to these official documents, the total number of employees based on contracts for full-time or piece-work engagements in 2017 was 520. But, these documents did not contain data on the number of men and women who are engaged as teachers. Based on data available on the internet websites of faculties of this University, there were 65 women engaged as teachers; all were full-time employees since these websites did not present persons engaged as teachers on other legal bases. Results confirmed, while women were not taking the managing positions, men were undoubtedly dominant in higher education institutions managing positions. Although women fairly successfully graduate from all three university study cycles, afterward they face the so-called „glass ceiling“, disabling them or making it very hard to officially enter the education institutions as employees, which limits any future advancement. Women who managed to become faculty members were very often faced with gender-based stigmatization and/or segregation. Further analyses should establish why women, as employees of HEIs, hesitate and decline to accept managing positions. Also, it is necessary to enhance the higher education institution’s methodology of reporting, for HEIs to provide clear data on the number of women engaged in the teaching process, and data on their status (assistants or senior assistants, and assistant, associate or full professors). When a total number of women employed as teaching, administrative and technical staff in an HEI is given, the actual state of gender equality in any of the mentioned three segments is presented. The importance of women’s participation in politics becomes also clear in this point since it is extremely important to have political awareness and readiness for solving problems and creating relevant policies for the above issues.
Data from clinical trials suggest that CT-confirmed nondisplaced scaphoid waist fractures heal with less than the conventional 8–12 weeks of immobilization. Barriers to adopting shorter immobilization times in clinical practice may include a strong influence of fracture tenderness and radiographic appearance on decision-making. This study aimed to investigate (1) the degree to which surgeons use fracture tenderness and radiographic appearance of union, among other factors, to decide whether or not to recommend additional cast immobilization after 8 or 12 weeks of immobilization; (2) identify surgeon factors associated with the decision to continue cast immobilization after 8 or 12 weeks. In a survey-based study, 218 surgeons reviewed 16 patient scenarios of CT-confirmed nondisplaced waist fractures treated with cast immobilization for 8 or 12 weeks and recommended for or against additional cast immobilization. Clinical variables included patient sex, age, a description of radiographic fracture consolidation, fracture tenderness and duration of cast immobilization completed (8 versus 12 weeks). To assess the impact of clinical factors on recommendation to continue immobilization we calculated posterior probabilities and determined variable importance using a random forest algorithm. Multilevel logistic mixed regression analysis was used to identify surgeon characteristics associated with recommendation for additional cast immobilization. Unclear fracture healing on radiographs, fracture tenderness and 8 (versus 12) weeks of completed cast immobilization were the most important factors influencing surgeons’ decision to recommend continued cast immobilization. Women surgeons (OR 2.96; 95% CI 1.28–6.81, p = 0.011), surgeons not specialized in orthopedic trauma, hand and wrist or shoulder and elbow surgery (categorized as ‘other’) (OR 2.64; 95% CI 1.31–5.33, p = 0.007) and surgeons practicing in the United States (OR 6.53, 95% CI 2.18–19.52, p = 0.01 versus Europe) were more likely to recommend continued immobilization. Adoption of shorter immobilization times for CT-confirmed nondisplaced scaphoid waist fractures may be hindered by surgeon attention to fracture tenderness and radiographic appearance.
Cold Atmospheric Plasma (CAP) is an ionized gas near room temperature. Its anti-tumor effect can be transmitted either by direct treatment or mediated by a plasma-treated solution (PTS), such as treated standard cell culture medium, which contains different amino acids, inorganic salts, vitamins and other substances. Despite extensive research, the active components in PTS and its molecular or cellular mechanisms are not yet fully understood. The purpose of this study was the measurement of the reactive species in PTS and their effect on tumor cells using different plasma modes and treatment durations. The PTS analysis yielded mode- and dose-dependent differences in the production of reactive oxygen and nitrogen species (RONS), and in the decomposition and modification of the amino acids Tyrosine (Tyr) and Tryptophan (Trp). The Trp metabolites Formylkynurenine (FKyn) and Kynurenine (Kyn) were produced in PTS with the 4 kHz (oxygen) mode, inducing apoptosis in Mel Im melanoma cells. Nitrated derivatives of Trp and Tyr were formed in the 8 kHz (nitrogen) mode, elevating the p16 mRNA expression and senescence-associated ß-Galactosidase staining. In conclusion, the plasma mode has a strong impact on the composition of the active components in PTS and affects its anti-tumor mechanism. These findings are of decisive importance for the development of plasma devices and the effectiveness of tumor treatment.
Introduction: Active aging is a process of optimizing of opportunities for health, participation, and safety to improve the quality of life as people age. Therapeutic exercises to strengthen muscles are especially important for the elderly, and the results of such exercises are positive in people with functional limitations. The aim of the study was to assess functional mobility of people in the 3rd age of life after programmed therapeutic exercises.Methods: The prospective study included two groups of 130 respondents over the age of 65 who came to the “Centre for Healthy Aging” in Novo Sarajevo in the period from September 1, 2014, until March 1, 2015. Using the time up and go test (TUG), the basic functional mobility was assessed and it represents the minimum time the respondent needs to get up from the armchair, walk a distance of three meters, turn around, and sit back in the armchair. We tested the respondents at the beginning, in the middle, and at the end of the study, which lasted for 6 months.Results: Analysis of the gender structure of the control and the test groups, using the Chi-square test, found a statistically significant difference, and in the test group, there were more female subjects than in the control group, χ2 = 50.620; p = 0.001. Analysis of the functional mobility of the respondents of the test groups using the TUG at the end of the study found that the respondents of the test group needed statistically significantly less time to perform the test (8.84 seconds) compared to the control group (9.59 seconds) and test Group B (9.41 seconds), F = 4.711; p = 0.041.Conclusion: Programmed therapeutic exercise leads to a significant improvement in functional mobility of persons in the 3rd age of life.
Information communication technologies are evolving rapidly and have huge impact on everyday life. This does not come without dangers, i.e., it is actively followed by wide range of malicious activities that impact the companies forcing them to protect their information at all costs. Cyber attacks today are usually consisting of multiple carefully planned hardly detectable steps causing severe damage to companies. This paper examines the capability of security information and event management (SIEM) system with applied partial rules in detecting the multi-step attacks. Fine tuning was focused on detecting partial attack patterns that were important and specific to environment and positive results were gained. The results show that when using the partial rule approach in SIEM for incident detection, the number of detected advanced multistage cyber attacks has increased, thereby contributing to the overall security in cyber space.
Following the idea of sustainability in food production, a yogurt premix based on beetroot (Beta vulgaris) pomace flour (BPF) was developed. BPF was granulated with lactose solution containing lactic acid bacteria (LAB) by a fluidized bed. Particle size increased ~30%. A decrease in Carr Index from 21.5 to 14.98 and Hausner ratio from 1.27 to 1.18 confirmed improved flowability of granulated BPF, whereas a decrease in water activity implied better storability. Yogurts were produced weekly from neat starters and granulated BPF (3% w/w) that were stored for up to one month (4 °C). High viability of Streptococcus thermophilus was observed. Less pronounced syneresis, higher inhibition of colon cancer cell viability (13.0–24.5%), and anti-Escherichia activity were ascribed to BPF yogurts or their supernatants (i.e., extracted whey). Acceptable palatability for humans and dogs was demonstrated. A survey revealed positive consumers’ attitudes toward the granulated BPF as a premix for yogurts amended to humans and dogs. For the first time, BPF granulated with LAB was used as a premix for a fermented beverage. An initial step in the conceptualization of a novel DIY (do it yourself) formula for obtaining a fresh yogurt fortified with natural dietary fiber and antioxidants has been accomplished.
Single seismometer structure Because of the lack of direct seismic observations, the interior structure of Mars has been a mystery. Khan et al., Knapmeyer-Endrun et al., and Stähler et al. used recently detected marsquakes from the seismometer deployed during the InSight mission to map the interior of Mars (see the Perspective by Cottaar and Koelemeijer). Mars likely has a 24- to 72-kilometer-thick crust with a very deep lithosphere close to 500 kilometers. Similar to the Earth, a low-velocity layer probably exists beneath the lithosphere. The crust of Mars is likely highly enriched in radioactive elements that help to heat this layer at the expense of the interior. The core of Mars is liquid and large, ∼1830 kilometers, which means that the mantle has only one rocky layer rather than two like the Earth has. These results provide a preliminary structure of Mars that helps to constrain the different theories explaining the chemistry and internal dynamics of the planet. Science, abf2966, abf8966, abi7730, this issue p. 434, p. 438, p. 443 see also abj8914, p. 388 Data from the InSight mission on Mars help constrain the structure and properties of the martian interior. For 2 years, the InSight lander has been recording seismic data on Mars that are vital to constrain the structure and thermochemical state of the planet. We used observations of direct (P and S) and surface-reflected (PP, PPP, SS, and SSS) body-wave phases from eight low-frequency marsquakes to constrain the interior structure to a depth of 800 kilometers. We found a structure compatible with a low-velocity zone associated with a thermal lithosphere much thicker than on Earth that is possibly related to a weak S-wave shadow zone at teleseismic distances. By combining the seismic constraints with geodynamic models, we predict that, relative to the primitive mantle, the crust is more enriched in heat-producing elements by a factor of 13 to 20. This enrichment is greater than suggested by gamma-ray surface mapping and has a moderate-to-elevated surface heat flow.
Single seismometer structure Because of the lack of direct seismic observations, the interior structure of Mars has been a mystery. Khan et al., Knapmeyer-Endrun et al., and Stähler et al. used recently detected marsquakes from the seismometer deployed during the InSight mission to map the interior of Mars (see the Perspective by Cottaar and Koelemeijer). Mars likely has a 24- to 72-kilometer-thick crust with a very deep lithosphere close to 500 kilometers. Similar to the Earth, a low-velocity layer probably exists beneath the lithosphere. The crust of Mars is likely highly enriched in radioactive elements that help to heat this layer at the expense of the interior. The core of Mars is liquid and large, ∼1830 kilometers, which means that the mantle has only one rocky layer rather than two like the Earth has. These results provide a preliminary structure of Mars that helps to constrain the different theories explaining the chemistry and internal dynamics of the planet. Science, abf2966, abf8966, abi7730, this issue p. 434, p. 438, p. 443 see also abj8914, p. 388 Data from the InSight mission on Mars help constrain the structure and properties of the martian mantle. A planet’s crust bears witness to the history of planetary formation and evolution, but for Mars, no absolute measurement of crustal thickness has been available. Here, we determine the structure of the crust beneath the InSight landing site on Mars using both marsquake recordings and the ambient wavefield. By analyzing seismic phases that are reflected and converted at subsurface interfaces, we find that the observations are consistent with models with at least two and possibly three interfaces. If the second interface is the boundary of the crust, the thickness is 20 ± 5 kilometers, whereas if the third interface is the boundary, the thickness is 39 ± 8 kilometers. Global maps of gravity and topography allow extrapolation of this point measurement to the whole planet, showing that the average thickness of the martian crust lies between 24 and 72 kilometers. Independent bulk composition and geodynamic constraints show that the thicker model is consistent with the abundances of crustal heat-producing elements observed for the shallow surface, whereas the thinner model requires greater concentration at depth.
Single seismometer structure Because of the lack of direct seismic observations, the interior structure of Mars has been a mystery. Khan et al., Knapmeyer-Endrun et al., and Stähler et al. used recently detected marsquakes from the seismometer deployed during the InSight mission to map the interior of Mars (see the Perspective by Cottaar and Koelemeijer). Mars likely has a 24- to 72-kilometer-thick crust with a very deep lithosphere close to 500 kilometers. Similar to the Earth, a low-velocity layer probably exists beneath the lithosphere. The crust of Mars is likely highly enriched in radioactive elements that help to heat this layer at the expense of the interior. The core of Mars is liquid and large, ∼1830 kilometers, which means that the mantle has only one rocky layer rather than two like the Earth has. These results provide a preliminary structure of Mars that helps to constrain the different theories explaining the chemistry and internal dynamics of the planet. Science, abf2966, abf8966, abi7730, this issue p. 434, p. 438, p. 443 see also abj8914, p. 388 Data from the InSight mission on Mars help constrain the structure and properties of the martian interior. Clues to a planet’s geologic history are contained in its interior structure, particularly its core. We detected reflections of seismic waves from the core-mantle boundary of Mars using InSight seismic data and inverted these together with geodetic data to constrain the radius of the liquid metal core to 1830 ± 40 kilometers. The large core implies a martian mantle mineralogically similar to the terrestrial upper mantle and transition zone but differing from Earth by not having a bridgmanite-dominated lower mantle. We inferred a mean core density of 5.7 to 6.3 grams per cubic centimeter, which requires a substantial complement of light elements dissolved in the iron-nickel core. The seismic core shadow as seen from InSight’s location covers half the surface of Mars, including the majority of potentially active regions—e.g., Tharsis—possibly limiting the number of detectable marsquakes.
Although functional asymmetry is very common and normal in professional athletes, the better interlimb symmetry between dominant and nondominant sides (bilateral symmetry) could contribute to successful performance in basketball. The aim of this study was to evaluate the importance of bilateral symmetry of the one-leg jumping and agility performances in differentiating basketball players according to their (i) playing position (guards, forwards, and centers) and (ii) performance levels (first division vs. second division). The participants were 102 professional male basketball players, with all members of the teams competing in the two highest national divisions at the moment of testing (height: 194.92 ± 8.09 cm; body mass: 89.33 ± 10.91 kg; 21.58 ± 3.92 years of age). Performance levels (first division, N = 58 vs. second division, N = 44) and playing positions (guards, N = 48; forwards, N = 22; centers, N = 32) were observed as dependent variables. We measured one-leg jumping capacities (running vertical jump and lay-up vertical jump), basketball-specific preplanned agility (CODS), and basketball-specific reactive agility (RAG), all executed on dominant and nondominant sides. Accordingly, the bilateral symmetry of jumping and agility was calculated by calculating the ratio of the corresponding performances on the dominant and nondominant sides. Factorial analysis of variance (performance levels × positions) indicated that the bilateral symmetry of one-leg jumping differentiated players according to their playing position, with better bilateral symmetry among guards (F-test = 6.11 (medium effect size) and 5.81 (small effect size), p < 0.05 for lay-up and running-jump symmetry, respectively). Performance levels significantly differed in the bilateral symmetry of lay-up jump, with better symmetry for first-division players (F-test = 10.11 (medium effect size), p < 0.001), which was mostly influenced by significant differences among guards. Playing positions and performance levels did not differ in bilateral symmetry of the CODS and RAG. The study reveals the importance of bilateral symmetry of the sport-specific performance in differentiating playing positions and performance levels in basketball. Further studies in other multidirectional sports and other sport-specific performances are warranted.
<p>The scattering of seismic waves is the signature of random heterogeneities, present in the lithospheric structure of a terrestrial planet. It is the result of refraction and reflection of the seismic waves generated by a quake, when they cross materials with different shear rigidity, bulk modulus, and density and therefore different seismic wave velocities, compared to the ambient space.  On Earth, the seismic waves show relatively weak scattering, identified in later arriving coda waves that follow the main arrivals of body waves and decay with time. In contrast, seismic wave scattering is much more significant on the Moon, where the high heterogeneous structure of the lunar megaregolith, produced through millions of years of impact bombardment, is a structure that creates an extreme scattering environment.</p> <p>The landing of the NASA InSight mission on Mars in 2018, which carried and deployed a seismometer for the first time on the Martian ground, offered a pristine dataset for the investigation and analysis of the characteristics of the scattering attenuation of the Martian crust and uppermost mantle which is important for understanding the structure of the Martian interior. Lognonné et al. (2020) used a methodology based on the radiative transfer model (Margerin et al., 1998) to offer the first constraints for the scattering and attenuation in the Martian crust. In this study, we performed a further examination based on more and newer events of the Martian Seismic Catalog (InSight Marsquake Service, 2021).</p> <p>The Marsquake Catalog contains events that are categorized according to the frequency content of the seismic signal (Clinton et al., 2021). In this study, we used 19 events of 4 different families, namely the Low Frequency, Broadband, High Frequency, and Very High Frequency events, for our investigation. We focused our investigation on the characteristics of the S-coda waveforms and for this reason, we worked on the respective energy envelopes. We manually picked the envelopes, defining the time window of the S-coda waves, as well the frequency range for each event, directly from the spectrograms of the events' signals, using an appropriately developed visual tool.</p> <p>We used a modeling approach (Dainty et al., 1974) that was developed for the computation of the energy envelopes of shallow events (Lunar impacts) and a diffusive, highly scattering layer, sitting over an elastic half-space. The energy envelope depends on the thickness of the diffusive layer, the range of the seismic ray, the diffusivity and the attenuation in the top layer, and the seismic wave velocity in the underneath elastic half-space. We analyzed all the tradeoffs between the terms of the modeling equation, namely the geometrical relationship of the velocity contrast between the diffusive layer and the elastic half-space with the seismic ray range and the diffusive layer thickness, the diffusivity with the diffusive layer thickness, and between the diffusivity and the velocity contrast of the two examined layers.</p> <p>The presence of the aforementioned tradeoffs made the definition of a unique model a very hard task, as the information for the azimuthal characteristics of the signal is not available for the examined events. This is a limitation that exists in seismology only while working with one station, with the InSight seismometer being the only station on a planet, and the amplitude of the seismic signal is not big enough to perform a specific polarization analysis and derive the azimuthal origin of the recorded signal. For this reason, we reviewed the fit between the modeling and the data, depending on the frequency content of the events.</p> <p>The Low Frequency and the Broadband events, which have a frequency content mainly below the tick noise detected at 1 Hz, could not satisfy the modeling approach of a simple diffusive layer. The spectral envelopes of the S-coda waves of these events are decaying very rapidly, which suggests an origin in a more elastic environment. This is in agreement with previous studies (Giardini et al., 2020) that suggest that these events are generated deeper in the Martian mantle. For this reason, we applied another approach to these signals, with an energy envelope equation designed for deep moonquakes (Dainty et al.,1974), but it was not either capable to fit the examined data envelopes, suggesting the absence of a very thick megaregolith structure on Mars.</p> <p>Based on the results of the High Frequency (HF) and Very High Frequency (VF) events we observed a range of possible paths and diffusivities that can satisfy the data and we investigated the tradeoffs between the parameters of a modeling equation that control the shape of the energy envelope for the events. The analysis of these tradeoffs does not permit us to make any assumptions about the depth of the diffusive region in the Martian crust and the upper mantle as their azimuthal characteristics are unknown and therefore it is not feasible to tell if the difference in the result analysis reflects vertical or lateral variations of the uppermost diffusive layer in the Martian lithosphere.</p> <p>The results of this study illustrate one of the challenges in working with single-station seismic data where event location information, including distance, azimuth, and depth are crucial for understanding the lateral variation in seismic properties of a planet. The existence of a seismic network on the planetary scale will improve the ability of phase peaking and location identification of the events and therefore it will give additional constraints for a similar analysis.</p> <p>References</p> <p>Clinton, J. F. et al. (2021). The Marsquake catalogue from InSight, sols 0–478.Phys Earth Planet In, 310:106595.</p> <p>Dainty,  A. M. et al. (1974). Seismic scattering and shallow structure of the Moon in Oceanus Procellarum.The Moon,9(1-2):11–29.</p> <p>Giardini, D. et al. (2020). The seismicity of Mars.Nat Geosci, 13(3):205–212.InSight Marsquake Service (2021). </p> <p>Mars Seismic Catalogue, InSight Mission; V5 2021-01-04.</p> <p>Lognonné, P. et al. (2020).  Constraints on the shallow elastic and anelastic structure of Mars from InSight seismic data.NatGeosci, 13(3):213–220.</p> <p>Margerin, L. et al. (1998).  Radiative transfer and diffusion of waves in a layered medium: new insight into coda Q.GeophysJ Int, 134(2):596–612.</p>
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