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ماوراء المنطق : استخدام العواطف عندما تتفاوض
يقدم كتاب ما وراء المنطق ل روجر فيشر ودانيال شابيرو طريقة للتعامل مع استراتيجية تمكنك من خلق انفعالات إيجابية ومن التعامل مع الانفعالات السلبية ولن تكون بعد الآن خاضعا لانفعالاتك أو انفعالات الآخرين وستكون مفاوضاتك أكثر أريحية وكفاءة وهذه الاستراتيجية فعالة بما يكفى لاستخدامها سواء أكانت مع زميل متصلب الرأي أو مقايض صعب الإرضاء أو مع شريك حياتك كذلك والكتاب يتناول الانفعالات لذا أضاف المؤلفين بعدا شخصيا فقد أوردا عددا من الأمثلة المستمدة من حياتهم الشخصية وكذلك من عملهم سنوات طويلة فى مجال المفاوضات.
Book
Selection of the Winding Type of Solid-State Transformers in Terms of Transmitting the Greatest Possible Power in the Frequency Range from 500 Hz to 6000 Hz
Solid-state transformer (SST) is an emerging technology that integrates with transformer power electronics converters and control. The most noticeable advantages of SST are the size and weight reduction compared with low-frequency transformers. Since this device is used in many devices such as smart grids, traction systems, systems with renewable energy sources (RESs) and electric vehicle charging devices, it is important to build a high-efficiency device at a low cost. The article evaluates a medium frequency transformer (SST) operating at a frequency of 500 Hz to 6000 Hz with coils wound with aluminum foil or Litz windings and of a grain-oriented electrical steel (GOES) core. The calculations were made using the 3D field method using the numerical finite element method, and the results were compared with the tests of the real model. The measurement method based on the Fourier analysis of real signals was used for the research.
Journal Article
Rapid expansion and international spread of M1UK in the post-pandemic UK upsurge of Streptococcus pyogenes
The UK observed a marked increase in scarlet fever and invasive group A streptococcal infection in 2022 with severe outcomes in children and similar trends worldwide. Here we report lineage M1
UK
to be the dominant source of invasive infections in this upsurge. Compared with ancestral M1
global
strains, invasive M1
UK
strains exhibit reduced genomic diversity and fewer mutations in two-component regulator genes
covRS
. The emergence of M1
UK
is dated to 2008. Following a bottleneck coinciding with the COVID-19 pandemic, three emergent M1
UK
clades underwent rapid nationwide expansion, despite lack of detection in previous years. All M1
UK
isolates thus-far sequenced globally have a phylogenetic origin in the UK, with dispersal of the new clades in Europe. While waning immunity may promote streptococcal epidemics, the genetic features of M1
UK
point to a fitness advantage in pathogenicity, and a striking ability to persist through population bottlenecks.
Exponential growth of toxigenic
Streptococcus pyogenes
M1
UK
lineage accounted for most of the 2022/2023 invasive infection upsurge in the UK. Authors provide evidence that M1
UK
first emerged in 2008, has genetic evidence of enhanced fitness, and has disseminated to 3 continents.
Journal Article
Thermal behavior of grain-oriented electrical steel wound core solid-state transformer
Purpose
This paper aims to propose a new design for high-power compact solid-state transformers (SSTs) made with grain-oriented electrical steel (GOES) wound cores that benefit from the natural reduction of iron losses at high temperatures.
Design/methodology/approach
An experimental approach, coupled with numerical and analytical investigations, is widely used for proving the validity of the proposed concept.
Findings
With cores much hotter than coils, the new design of medium frequency transformers can be used for building compact SSTs that rated powers and common-mode insulation voltages much higher than existing ones with similar efficiencies.
Research limitations/implications
The thermal design must provide a large difference between core and coil temperatures in a reasonable volume.
Practical implications
The increasing number of intermittent renewable sources place electric grid stability at risk. Smart nodes, made of SSTs, improve the global grid stability because they are able to provide real-time control of energy fluxes at critical points. In railway applications, high-power SST cells can be distributed along the train providing a larger volume for passengers.
Social implications
The increasing part of electricity in a flexible grid requires performant and high-power SSTs made with components that have an environmental footprint as low as possible.
Originality/value
This paper proves that the design of high-power transformers with GOES wound cores much hotter than coils is possible. It proposes also a thermal equivalent circuit that helps the design.
Journal Article
Cell-Free DNA Hypermethylation in Patients with Acute Pancreatitis
Cell-free DNA (cfDNA) promoter hypermethylation shows promise as a blood-based biomarker for pancreatic cancer, and similar alterations may occur in acute pancreatitis (AP). This study investigated the cfDNA hypermethylation profile of AP patients over time, compared with healthy controls, and its association with AP severity markers. A prospective longitudinal study including hospitalized AP patients and healthy controls was conducted. Methylation-specific PCR of a 23-gene panel was performed on plasma collected at inclusion (T0), 6 weeks (T6W), 6 months (T6M), and 7–8 years (T8Y). Associations between gene hypermethylation and clinical markers of AP severity—CRP, leukocyte count, creatinine, hospital stay, and complications—were evaluated. AP patients had a significantly higher mean number of hypermethylated genes at T0 (7.4, 95% CI: 6.8–8.0) compared with the controls (3.3, 95% CI: 2.8–3.8; p < 0.01). The mean number decreased over time to 3.2 (95% CI: 2.4–4.1) at T8Y. Total hypermethylation was positively associated with CRP (ρ = 0.39; p = 0.0018), leukocytes (ρ = 0.35; p = 0.0052), and hospital stay (ρ = 0.27; p = 0.0375). AP patients exhibited significantly higher cfDNA hypermethylation at disease onset, which normalized over time. Total hypermethylation showed positive associations with several markers of AP severity.
Journal Article
Genome analysis following a national increase in Scarlet Fever in England 2014
Background
During a substantial elevation in scarlet fever (SF) notifications in 2014 a national genomic study was undertaken of
Streptococcus pyogenes
(Group A Streptococci, GAS) isolates from patients with SF with comparison to isolates from patients with invasive disease (iGAS) to test the hypotheses that the increase in SF was due to either the introduction of one or more new/emerging strains in the population in England or the transmission of a known genetic element through the population of GAS by horizontal gene transfer (HGT) resulting in infections with an increased likelihood of causing SF. Isolates were collected to provide geographical representation, for approximately 5% SF isolates from each region from 1
st
April 2014 to 18
th
June 2014. Contemporaneous iGAS isolates for which genomic data were available were included for comparison. Data were analysed in order to determine
emm
gene sequence type, phylogenetic lineage and genomic clade representation, the presence of known prophage elements and the presence of genes known to confer pathogenicity and resistance to antibiotics.
Results
555 isolates were analysed, 303 from patients with SF and 252 from patients with iGAS. Isolates from patients with SF were of multiple distinct
emm
sequence types and phylogenetic lineages. Prior to data normalisation,
emm
3 was the predominant type (accounting for 42.9% of SF isolates, 130/303 95%CI 37.5–48.5; 14.7% higher than the percentage of
emm
3 isolates found in the iGAS isolates). Post-normalisation
emm
types, 4 and 12, were found to be over-represented in patients with SF versus iGAS (
p
< 0.001). A single gene,
ssa,
was over-represented in isolates from patients with SF. No single phage was found to be over represented in SF vs iGAS. However, a “meta-ssa” phage defined by the presence of :315.2, SPsP6, MGAS10750.3 or HK360ssa, was found to be over represented. The HKU360.vir phage was not detected yet the HKU360.ssa phage was present in 43/63
emm
12 isolates but not found to be over-represented in isolates from patients with SF.
Conclusions
There is no evidence that the increased number of SF cases was a strain-specific or known mobile element specific phenomenon, as the increase in SF cases was associated with multiple lineages of GAS.
Journal Article
Voltage distribution in the windings of high temperature inverter-fed motors
Purpose
High-temperature (HT°) motors are made with inorganic coils wound with a ceramic-coated wire. They must be carefully designed because the HT° insulating materials have a lower breakdown voltages than the polymers used for insulating standard machines.
Design/methodology/approach
The voltage distribution between stator coils is computed with high-frequency (HF) equivalent circuits that consider the magnetic couplings and the stray capacitances. Two time scales are used for getting a fast computation of very short voltage spikes. For the first step, a medium time scale analysis is performed considering a simplified equivalent circuit made without any stray capacitance but with the full PWM pattern and the magnetic couplings. For the second step, a more detailed HF equivalent circuit computes voltage spikes during short critical time windows.
Findings
The computation made during the first step provides the critical time windows and the initial values of the state variables to the second one. The rise and fall time of the electronic switches have a minor influence on the maximum voltage stress. Conversely, the connection cable length and the common-mode capacitances have a large influence.
Research limitations/implications
HF equivalent circuits cannot be used with random windings but only to formed coils that have a deterministic position of turns.
Practical implications
The proposed method can be used designing of HT° machine windings fed by PWM inverter and for improving the coils of standard machine used in aircraft’s low-pressure environments.
Originality/value
The influence of grounding system of the DC link is considered for computing the voltage spikes in the motor windings.
Journal Article
Transcriptomic and macroevolutionary evidence for phenotypic uncoupling between frog life history phases
Anuran amphibians undergo major morphological transitions during development, but the contribution of their markedly different life-history phases to macroevolution has rarely been analysed. Here we generate testable predictions for coupling versus uncoupling of phenotypic evolution of tadpole and adult life-history phases, and for the underlying expression of genes related to morphological feature formation. We test these predictions by combining evidence from gene expression in two distantly related frogs,
Xenopus laevis
and
Mantidactylus betsileanus
, with patterns of morphological evolution in the entire radiation of Madagascan mantellid frogs. Genes linked to morphological structure formation are expressed in a highly phase-specific pattern, suggesting uncoupling of phenotypic evolution across life-history phases. This gene expression pattern agrees with uncoupled rates of trait evolution among life-history phases in the mantellids, which we show to have undergone an adaptive radiation. Our results validate a prevalence of uncoupling in the evolution of tadpole and adult phenotypes of frogs.
In animals with complex life cycles, selection on one life phase may constrain adaptation in another phase. Here the authors find that, during the adaptive radiation of mantellid frogs, the evolution of tadpole and adult morphologies has been uncoupled through phase-specific gene expression.
Journal Article
Measurement of the leakage flux in the vicinity of a transformer core
PurposeThis study presents a new method for the detection of faults in large transformer cores. It is based on the analysis of leakage flux components in the vicinity of the sheet stack. The purpose of this study is to provide a nondestructive analysis tool for transformer cores during the assembly process to detect accidental defects such as inter-laminar short circuits.Design/methodology/approachThe different components of the leakage flux allow localization of the fault in the stack and also permit to assess its severity. Out of the many kinds of defects which may appear in a transformer core, this method only detects those which actually cause an increase in the transformer’s global iron losses, which are thus the most detrimental.FindingsThe proposed method allows a more efficient control of the quality of the cores during their manufacturing process. Until now, it was only possible to know the quality of the core when the transformer was fully assembled.Research limitations/implicationsThe accuracy of the method depends on the size of the defect and may request many measurements to give usable information.Practical implicationsControlling iron losses in a core during its construction avoids heavy dismantling operations, both financially and temporally.Originality/valueThis method can help transformer manufacturers optimize their building process. In addition, the method remains effective regardless of the size of the core considered.
Journal Article