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The purpose of this study was to examine contextual factors (empowerment, ownership, and accountability) that facilitate and promote exploration and exploitation behavior. Data were obtained from an American manufacturing company using employee and supervisor surveys (n = 297). Findings indicate that empowerment improved exploitation and that when employees perceived they would have to be accountable for their actions, employees who felt empowered showed lower gains in exploration behaviors compared with those who felt less empowered; in contrast, those having feelings of ownership exhibited higher gains in exploration behavior than those who scored low in ownership. Although ownership was theorized to have a positive effect on exploitative behavior, we found evidence for its negative effects instead. We contribute to the limited individual-level ambidexterity literature by providing empirical evidence on the effects of contextual factors on ambidextrous behavior. This knowledge could help firms better manage employee behavior and implement effective supervisory oversight.
This Research Communication describes the relationship between casein, free fatty acids (FFAs) and the storage period of ultra-high temperature-treated (UHT) whole milk observed for a period of 120 d of labelled shelf-life. Moreover, we aim to estimate the daily rate of casein degradation in UHT whole milk, and the total length of time estimated for its full degradation. With this aim, ten sets of samples were evaluated from batches of UHT milk manufactured by a dairy processing plant in Parana State, Brazil on 10 different days. Each set was comprised of one liter of raw milk and 12 units of 1 litre cartons of UHT milk, and represented one batch of production. Total mesophilic (TMC), psychrotrophic (TPC), and somatic cell counts (SCC) of raw milk were assessed. UHT milk was assessed for fat (%), sialic acid (mg/l), casein (%), and FFA contents. TMC ranged from 3·5 × 106 to 3·1 × 107 CFU/ml; TPC, from 106 UFC/ml and higher; and SCC, from 18 × 104 SC/ml to 4·83 × 105 CS/ml. Casein (r = −0·991; R2 = 0·9822) and FFA (r = 0·962; R2 = 0·9245) contents, and storage time of UHT milk were correlated (P < 0·05). The rate of casein hydrolysis was estimated as 0·021 g/100 g UHT whole milk/day. A complete breakdown of casein was estimated to occur by the 560th day post-manufacture. Although age gelation was not observed in our study, the report herein corroborates the understanding that the microbiological quality and SCC of raw milk are important components involving the integrity of casein and lipids of UHT milk during shelf-life.
We present a fast method to prepare hybrid materials of polyaniline (PAni) with carbon nanotubes (CNTs, both undoped and nitrogen-doped) by ball milling without solvents or strong oxidants. PAni forms nanoparticles, attached to CNTs in a nanocomposite structure, with the nanotubes well dispersed among the polymer. This is achieved with only a few minutes of ball milling. Raman spectroscopy confirms that PAni was synthesized in its conductive state and suggests a good CNT–PAni interaction, particularly with nitrogen-doped CNTs. We found that water increased polymer yield, which we optimized, together with the nanocomposite conductivity, as function of amount of water and of oxidant (FeCl3). The nanocomposite conductivity is four orders of magnitude higher than that of PAni, for both types of nanotubes. Scanning electron microscopy and X-ray diffraction both show negligible damage to the CNT during this mechanosynthesis procedure, while dry milling and milling CNT in water without aniline does damage nanotubes, indicating that the reaction absorbs most of the mechanical energy.
The purpose of this study is to assess the discourse of people with disabilities regarding their perception of discrimination and stigma. Semi-structured interviews were conducted with ten adults with physical disabilities, ten with hearing impairments and seven with visual impairments. The agreement between the coders showed an excellent reliability for all three groups, with kappa coefficients between .82 and .96. Differences were assessed between the three groups regarding the types of discrimination they experienced and their most frequent emotional responses. People with physical disabilities mainly reported being stared at, undervalued, and subtly discriminated at work, whereas people with hearing impairments mainly reported encountering barriers in leisure activities, and people with visual impairments spoke of a lack of equal opportunities, mockery and/or bullying, and overprotection. Regarding their emotional reactions, people with physical disabilities mainly reported feeling anxious and depressed, whereas people with hearing impairments reported feeling helpless, and people with visual impairments reported feeling anger and self-pity. Findings are relevant to guide future research and interventions on the stigma of disability.
Multiwall carbon nanotubes (MWCNTs) are utilized to resolve low coupling coefficient issue by dispersing MWCNTs in poly(vinylidene fluoride) matrix to create stress reinforcing network, dispersant, and electron conducting functions for barium titanate (BT) nanoparticles. Various BT and MWCNT percentages of nanocomposite film are fabricated by FDM three-dimensional (3D) printing which can simplify the fabrication process as well as lower cost and design flexibility. Increasing MWCNTs and BT particles gradually increase piezoelectric coefficient (d31) by 0.13 pC/N with 0.4 wt%-MWCNTs/18 wt%-BT. These results provide not only a technique to print piezoelectric nanocomposites but also unique materials combination for sensor application.
The crystal structure of karibibite, Fe33+(As3+O2)4(As23+O5)(OH), from the Urucum mine (Minas Gerais, Brazil), was solved and refined from electron diffraction tomography data [R1 = 18.8% for F > 4σ(F)] and further confirmed by synchrotron X-ray diffraction and density functional theory (DFT) calculations. The mineral is orthorhombic, space group Pnma and unit-cell parameters (synchrotron X-ray diffraction) are a = 7.2558(3), b = 27.992(1), c = 6.5243 (3) Å, V = 1325.10(8) Å3, Z = 4. The crystal structure of karibibbite consists of bands of Fe3+O6 octahedra running along a framed by two chains of AsO3 trigonal pyramids at each side, and along c by As2O5 dimers above and below. Each band is composed of ribbons of three edge-sharing Fe3+O6 octahedra, apex-connected with other ribbons in order to form a kinked band running along a. The atoms As(2) and As(3), each showing trigonal pyramidal coordination by O, share the O(4) atom to form a dimer. In turn, dimers are connected by the O(3) atoms, defining a zig-zag chain of overall (As3+O2)n-n stoichiometry. Each ribbon of (Fe3+O6) octahedra is flanked on both edges by the (As3+O2)n-n chains. The simultaneous presence of arsenite chains and dimers is previously unknown in compounds with As3+. The lone-electron pairs (4s2) of the As(2) and As(3) atoms project into the interlayer located at y = 0 and y = ½, yielding probable weak interactions with the O atoms of the facing (AsO2) chain.
The DFT calculations show that the Fe atoms have maximum spin polarization, consistent with the Fe3+ state.
This paper is focused on explaining the radiation test in temperature performed on the Engineering and Qualification Model of the Medium Gain Antenna Radiofrequency (MGA-RFA) Assembly of ESA's BepiColombo mission. The goal of this program is to observe and study Mercury and its surroundings in a very demanding environment in terms of temperature and radiation. The MGA is an X-band two-axis steerable horn, which provides bidirectional communications between spacecraft and Earth as backup of the High Gain Antenna and also operates as primary communication link at several mission stages or conditions. The paper presents the measurement set-up for the qualification campaign of the antenna, where it was necessary to characterize the antenna in a representative thermal environment, and the results obtained from this test. Results of test up to 150°C show how gain and radiation pattern shapes are slightly affected by thermal stress, but without jeopardizing mission requirements. In addition, by analyzing correlation of this test with RF analysis in the same thermal conditions, it becomes possible to accurately extrapolate the MGA-RFA behavior up to temperatures of more than 500°C. This fact allowed the successful space qualification of this model.
One of the most important complications of Kawasaki disease is the development of giant coronary aneurysms. Risk factors for their development are still not clear.
A retrospective analysis was conducted at the National Institute of Paediatrics in Mexico City, Mexico. It included all patients with a diagnosis of acute Kawasaki disease between August, 1995 and August, 2015. Clinical and laboratory findings, as well as echocardiographic measurements, were recorded. Patients with giant coronary aneurysms (z-score⩾10) were compared with the rest of the patients. A value of p<0.05 was considered statistically significant. Odds ratios and their 95% confidence intervals were calculated to define risk factors.
During the study period, 416 patients were diagnosed with Kawasaki disease. Of them, 34 developed giant coronary aneurysms during the acute stage of the disease. In the multivariate analysis, patients younger than 1 year, those with a higher duration of illness at the time of diagnosis, and those who received additional intravenous immunoglobulin showed a significantly higher frequency of giant coronary aneurysms.
One of the main factors associated with the development of giant coronary aneurysms was the delay in the diagnosis of Kawasaki disease. This finding highlights the importance of maintaining a high suspicion of the disease, which would enable an early diagnosis and prompt treatment and decrease the risk for developing giant coronary aneurysms.
The Recorrido Arqueológico de Coixtlahuaca (RAC) presents period-by-period settlement pattern maps for the valley of Coixtlahuaca in the northern Mixteca Alta. The RAC project made improvements in full-coverage survey methods. We identify limitations and suggest that similar projects in the future need to resolve several management and budget problems. The survey revealed two periods of heavy occupation, 700–300 BC and AD 1200–1520, separated by a long period of lower population. Archaeological and historical data indicate that during the AD 1200–1520 period, and probably earlier, small landholders organized in strong communities managed an intensive agroecosystem, investing in landesque capital. Urbanization was impressive, yet cities were aggregations of communities and barrios. Today local citizens pose questions about how the large prehispanic population could have organized and sustained itself; these questions coincide with anthropological interest in collective agency, property, landesque capital, and collapse.
Despite how important it is to assess executive functioning in persons with Intellectual Disability (ID), instruments adapted and validated for this population are scarce. This study’s primary goal was to find evidence for the validity of the ID version of the Tower of London (TOLDXtm) test in persons with mild (IDMi) and moderate (IDMo) levels of ID with Down Syndrome (DS). A multicenter study was carried out. Subjects (n = 63, ≥ 39 years old) had DS with mild (n = 39) or moderate ID (n = 24) with no minor neurocognitive disorder or Alzheimer’s disease. Assessment protocol: TOLDXtm for ID, Kaufman Brief Intelligence Test Second Edition (K-BIT II), Cambridge Examination for Mental Disorders of Older People with Down’s Syndrome and Others with Intellectual Disabilities (CAMDEX-DS), Weigl’s Color-Form Sorting Test (WCFST), Barcelona Test for Intellectual Disability (BT-ID), and the Behavior Rating Inventory of Executive Function (BRIEF-P). The internal consistency (IDMi and IDMo), factor structure of the different subscales, and relationship between TOLDXtm subscales and other cognitive measures (BT-ID, WCFST, and BRIEF-P) were analyzed. A normative data table with ID population quartiles is provided. TOLDXtm for ID showed a robust one factor structure and coherentassociations with other, related neuropsychological instruments. Significant differences between IDMi and IDMo on movement-related variables like Correct (Corr; p = .002) and Moves (Mov; p = .042) were observed, along with good internal consistency values, Corr (α = .75), Mov (α = .52). Regarding internal consistency, no between-groups differences were observed (all p-value > 0.05). The TOLDXtm for ID is thus an instrument, supported by good validity evidence, to evaluate problem-solving and planning in ID. It distinguishes between individuals with mild and moderate ID, and is highly associated with other measures of executive functioning.
Sea ice is generally covered with snow, which can vary in thickness from a few centimeters to >1 m. Snow cover acts as a thermal insulator modulating the heat exchange between the ocean and the atmosphere, and it impacts sea-ice growth rates and overall thickness, a key indicator of climate change in polar regions. Snow depth is required to estimate sea-ice thickness using freeboard measurements made with satellite altimeters. The snow cover also acts as a mechanical load that depresses ice freeboard (snow and ice above sea level). Freeboard depression can result in flooding of the snow/ice interface and the formation of a thick slush layer, particularly in the Antarctic sea-ice cover. The Center for Remote Sensing of Ice Sheets (CReSIS) has developed an ultra-wideband, microwave radar capable of operation on long-endurance aircraft to characterize the thickness of snow over sea ice. The low-power, 100 mW signal is swept from 2 to 8 GHz allowing the air/snow and snow/ ice interfaces to be mapped with 5 cm range resolution in snow; this is an improvement over the original system that worked from 2 to 6.5 GHz. From 2009 to 2012, CReSIS successfully operated the radar on the NASA P-3B and DC-8 aircraft to collect data on snow-covered sea ice in the Arctic and Antarctic for NASA Operation IceBridge. The radar was found capable of snow depth retrievals ranging from 10 cm to >1 m. We also demonstrated that this radar can be used to map near-surface internal layers in polar firn with fine range resolution. Here we describe the instrument design, characteristics and performance of the radar.
Currently, few musical expressions are as massive and as popular in Colombia as the so-called New Colombian Music (NCM). The term NCM has been used in recent years to refer to a marked tendency between young musicians who seek to “recover and reinterpret the local music” through an ambiguous and undetermined musical form (Santamaria 2). Drawing on other musical genres—for example, bambuco, cumbia, vallenato—that in the past were elevated to the status of “national music,” it is difficult to associate NCM with a specifc region within the Colombian territory. Nonetheless, the NCM label has demonstrated a strategic elasticity to market new national sounds and to connect these with World Music global festivals, as well as with state cultural politics and mass media agenda. Thanks to media dissemination, these “wordly” music productions blur and superimpose local and national identities as well as the public and private divide.
The process of NCM popularization in the national and international arenas has been possible thanks to diverse political, economic, and cultural dynamics: the celebration of cultural diversity that followed the adoption of the new Constitution in 1991; the multicultural rhetoric of the market and certain cultural circuits; the growing importance of cultural industries in the national economy; the constant demographic and migratory movements within and outside the country; the implementation of Colombia Is Passion and The Answer Is Colombia, the two institutional campaigns that branded Colombia and aligned the nation within territorial marketing logics to create an attractive destination for the foreign investor as well as tourists. Significantly, several of these dynamics emerging from the NCM phenomenon can be found in media outlets such as Al Jazeera English's Playlist: “Colombia, although sadly widely known for its drugs trade and violent, internal conflicts, is also witnessing a new musical movement, as a growing number of passionate and vocal musicians are keen to show their country in a new light…. The future of Colombian music may well lie in fusion, as bands seek out international audiences for their unique sounds.”
The objective of this study was to apply a decision training programme, based on the use of video-feedback and questioning, in real game time, in order to improve decision-making in volleyball attack actions. A three-phase quasi-experimental design was implemented: Phase A (pre-test), Phase B (Intervention) and Phase C (Retention). The sample was made up of 8 female Under-16 volleyball players, who were divided into two groups: experimental group (n = 4) and control group (n = 4). The independent variable was the decision training program, which was applied for 11 weeks in a training context, more specifically in a 6x6 game situation. The player had to analyze the reasons and causes of the decision taken. The dependent variable was decision-making, which was assessed based on systematic observation, using the “Game Performance Assessment Instrument” (GPAI) (Oslin, Mitchell, & Griffin, 1998). Results showed that, after applying the decision training program, the experimental group showed a significantly higher average percentage of successful decisions than the control group F(1, 6) = 11.26; p = .015; η2p = .652; 95% CI [056, 360]. These results highlight the need to complement the training process with cognitive tools such as video-feedback and questioning in order to improve athletes’ decision-making.
The order Spiriferinida represented a significant group whose extinction is linked to the early Toarcian mass extinction event. The genus Cisnerospira Manceñido, 2004, conspicuous representative of this group in the Early Jurassic of the western Tethys, is analyzed from a systematic standpoint, grounded mainly on evidence from the Subbetic domain, and its initial diagnosis is revised accordingly. A definitive suprageneric position within the subfamily Paralaballinae is formally proposed in the light of new data herein provided. Both external and internal diagnostic features and the generic and intraspecific variability are described through the analysis of the Cisnerospira species recorded in the easternmost Subbetic area, i.e., Cisnerospira adscendens (Deslongchamps, 1858), C. aff. adscendens, C. angulata (Oppel, 1861), and C.? sylvia (Gemmellaro, 1882). In addition, their interrelation with other records from several Tethyan basins is addressed, and the generic spectrum has been extended to include several species with high morphological affinity. This characterization thus contributes to clarify certain ambiguities in the systematics of the spiriferinids, which entails a complex taxonomy mainly based on the external features, where the ribbing pattern was given foremost classificatory value due to the lack of more reliable generic diagnostic criteria. Furthemore, a morphofunctional analysis performed in Cisnerospira reveals a presumable epibenthonic libero-sessile way of life, and two alternative adaptive strategies are discussed: resting on and/or sticking in substrates with different degree of consolidation, providing a significant hydrodynamic stability to the shell.
The miniaturization of shells, often observed in Mesozoic brachiopods, is analyzed in two species of the well-known genus Homoeorhynchia. We investigated shell development in the context of recent works that consider growth as a function of size, shape, and age. The miniaturization results from heterochronic disturbances during development. Although these shells exhibit a large morphological plasticity, architectural constraints limit their morphogenesis, so that small adult specimens are not exactly reduced replicas of large ones. Adult morphology depends largely on the pattern of rib formation, with miniaturization arising by two different processes affecting this pattern: predisplacement of the appearance of ribs in H. meridionalis and acceleration in H. cynocephala. The first case seems to be a reversible process without evolutionary consequences, but the second occurs within an evolutionary trend. In both cases, the miniaturization seems to be related to environmental influences. Study of the growth pathway of these species allows recognition of basic characters in the morphological variation of populations.