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This paper provides a mathematical description based on the theory of differential equations, for the dynamics of lactate production and removal. Analytical and numerical results for training/exercise of endurance of athletes are presented based on the common concept of training impulse (Trimp). The relationships between activity, production rate, and removal strategies of lactate are studied. Parameters are estimated from published data. A model for optimum removal of lactate after exercise is developed. The model provides realistic predictions when compared with experimental results. We show some specific examples for the usefulness of the mathematical model by studying some recent problems discussed in the literature. (a) Is interval exercise more beneficial than steady-state exercise? (b) What is the optimum aerobic power during recovery? We discuss whether steady-state exercise gives higher Trimp than interval exercise, when imposing an upper boundary for the lactate concentration as a constraint. The model allows for testing all imaginable kinds of steady-state and interval exercises in search of the optimal exercise regime for individuals with various kinds of characteristics. In general, the dynamic model constitute a powerful tool describing the processes by which the concentration of lactate can be studied and controlled to decrease fatigue and increase endurance.

This study investigates the influence of mixed cascade failures on the resilience of manufacturing enterprise supply chain networks, which are susceptible to disruptions from upstream and downstream enterprises due to external uncertainties. We propose a single-layer directed network model to examine mixed cascade failures and analyze the effectiveness of protection and recovery strategies for improving network resilience through extensive simulation experiments. The numerical analysis yields the following key findings: (i) Under targeted attacks, the Erdős–Rényi (ER) network exhibits marginally enhanced robustness, whereas the Barabási–Albert (BA) network proves to be more resilient against random attacks. (ii) Effectively mitigating failure risk and reducing the likelihood of failure can be accomplished by increasing the upper load capacity limit and decreasing the lower load capacity limit for manufacturing firms. Furthermore, a comprehensive approach to protection and recovery measures strengthens the stability of supply chain networks in the face of external risks. (iii) Constraints, such as epidemic control measures and infrastructure damage, may impede the recovery process of manufacturing firms’ supply chains when addressing external uncertainties.

Indonesia, Southeast Asia's most populous state and its largest economy, was deeply affected by the economic crisis of 1997–1998. Its economic contraction in 1998, of over 13%, was the sharpest among all four crisis-affected East Asian economies. This followed three decades of virtually uninterrupted, rapid economic growth. The country's economic crisis was accompanied by regime collapse, resulting in the departure of then President Suharto after 32 years of authoritarian rule. This paper examines the country's socioeconomic development in the decade since the crisis, in the context of the earlier growth, and the very different institutions of economic governance operating under the new democratic regime of weakened central authority and many more economic policy actors. The main conclusions are that growth and macroeconomic stability have been restored surprisingly quickly, but that microeconomic policy and the investment climate are less predictable.

We present a new method for simultaneously determining three-dimensional (3D) motion and structure of a nonrigid object from its uncalibrated two-dimensional (2D) data with Gaussian or non-Gaussian distributions. A nonrigid motion can be treated as a combination of a rigid component and a nonrigid deformation. To reduce the high dimensionality of the deformable structure or shape, we estimate the probability distribution function (PDF) of the structure through random sampling, integrating an established probabilistic model. The fitting between the observations and the estimated 3D structure will be evaluated using the pooled variance estimator. The recovered structure is only available when the 2D feature points have been properly corresponded over two image frames. Applications of the proposed method to both synthetic and real image sequences are demonstrated with promising results.

Inverted biomass pyramids (IBPs) seem to be extremely rare in natural communities. Until recently, the only examples have been in freshwater and marine planktonic communities. In 2002 and 2008, investigators documented inverted biomass pyramids for nearly pristine coral reef ecosystems within the NW Hawaiian islands and the Line Islands, where apex predator abundance comprises up to 85% of the fish biomass. Large predator:prey biomass ratio seems to be a signature of nearly pristine coral reefs. While the mechanism responsible for the IBP for homogeneously mixed planktonic communities seems to be well understood, this mechanism is not strictly applicable to nearly pristine coral reefs where much of the prey use coral as refuge and are inaccessible to the predators. We construct a mathematical model with an explicit refuge to illustrate a new biologically plausible mechanism that can explain stable IBPs in nearly pristine coral reefs. New modeling components include a refuge of explicit size, a refuge size dependent functional response, and refuge size dependent prey growth rate. Utilizing realistic life history parameters of coral reef fishes, our model exhibits a stable inverted biomass pyramid. We prove that all fishing decreases the biomass ratio and sufficiently strong fishing transforms the inverted biomass pyramid to be bottom heavy. Finally we use our model to test the conjecture that pristine coral reefs will rebound faster from environmental shocks and find that it is not always true.

In order to understand, in terms of the epidemiology of a disease, the consequences of having a population which can recover from the disease back to a state of susceptibility and the additional effects of recovery to immunity, we have formulated and compared a series of models; each includes a biological feature known to occur in a real host-pathogen system. For example, vertical transmission of the disease or free living infective stages of the pathogen. Taken together, these models, in general, follow predictable patterns of behaviour. There are exceptions, but these can be explained in terms of some sort of density dependence or time delay written into the framework of the model.

Theoretically, working excessively hard should be related negatively with well-being; however, the empirical literature does not consistently indicate that entrepreneurs are lower in well-being than people working in other jobs. The present article introduces a study of 101 entrepreneurs differentiating between different types of working hard: Workaholism and work engagement. While workaholism implies a work obsession, work engagement implies working hard in a fulfilling and positive way. Results indicate that workaholism is negatively and work engagement is positively related with well-being. Moreover, the negative relationships of workaholism are minimized by detaching from work during off-work hours.

Software failures and human errors are the most common reasons of inoparability of computer systems. Computers are increasingly reliable, but the level of transcient faults, caused by errors hidden in the programs, remains the same. For this reason software is becoming the key factor in the synthesis of highly reliable systems. Software errors do not result from operation, they either exist from the start or are inserted when patching or upgrading it. Some errors result from incorrect human interaction or unexpected environmental changes. Assessment of software impact requires functional-reliability approach to reliability analysis: the software fault occurs when it causes incorrect operation and not when it is introduced to the system. It is proposed to use software reliability models in system analysis, to predict the intensity of software faults. The software recovery after a failure is realized by restarts of various extend (microrestarts, minirestarts and macrorestarts). The impact of software failures and restarts on system availability is assessed.

The purpose of this study was to compare the initial and final outcome range of motion in the MCP-J and PIP-J of single digit Dupuytren's Contracture treated with either open surgical excision or manipulation after collagenase clostridium histolyticum (CCH; Xiapex) injection. Material: Ten patients in either group. The range of motion measurements were statistically compared using the student t-test with a p-value of 0.05. There was no statistical difference in the pre-treatment status of the total active range of movement (TAM) between the two groups. Results: Open surgical release achieved a statistically better initial outcome in combined total passive range of movement than the xiapex group (p = 0.0047), but at the final outcome the better TAM measurement at the MCP-J after surgery was not statistically significant. However, the total active range of movement was statistically better at the PIP-J level in the xiapex group (p = 0.01) and the MCP-J and PIP-J combined total active range of movement was statistically better in the xiapex group (p = 0.0258). Conclusion: Surgery achieved better initial outcome at both MCP-J and PIP-J levels, and at discharge, only extension in the MCP-J level was statistically better after open excision. However the final outcome was statistically better at the PIP-J level in extension (p = 0.006) and total active movement (TAM) (p = 0.008) after treatment with collagenase clostridium histolyticum. Further studies are required to assess the long-term differences between the two groups and to investigate the outcomes for patients with multi-digit involvement.

The observational data from the Spine Patient Outcomes Research Trial (SPORT) confirm the superiority of surgical over conservative management of symptomatic degenerative spondylolisthesis. The most common reported neurologic complications after lumbar posterior decompression and fusion are implant malposition, contralateral foraminal stenosis, hematoma/seroma, arachnoiditis, and nerve root oedema or vascular underlying causes.

The current study reported that the patient developed unexpected left side neurological deficit after conventional lumbar posterior spinal decompression surgery for degenerative spondylolisthesis. No intraoperative dural insult. The computer topography (CT) scan and magnetic resonance imaging (MRI) of the spine after index surgery show adequate canal and foraminal decompression. No hardware-related complications or compressive hematoma could explain the patient’s symptoms. The patient recovered completely after removing the redundant posterolateral bone graft. The theory behind that is aggressive posterolateral dissection over the transverse process and abundant application of the bone graft might compress or injure the lumbar plexus. So, we suggested a delicate dissection posterolaterally and only a reasonable amount of bone graft could be applied to prevent such a devastating neurological complication.

In this paper, we consider a market with a term structure of credit risky bonds in the single-name case. We aim at minimal assumptions extending existing results in this direction: first, the random field of forward rates is driven by a general semimartingale. Second, the Heath–Jarrow–Morton (HJM) approach is extended with an additional component capturing those future jumps in the term structure which are visible from the current time. Third, the associated recovery scheme is as general as possible, it is only assumed to be nonincreasing. In this general setting, we derive generalized drift conditions which characterize when a given measure is a local martingale measure, thus yielding no asymptotic free lunch with vanishing risk (NAFLVR), the right notion for this large financial market to be free of arbitrage.

This paper documents the economic and financial recovery of East Asia based on its real GDP, export, currency value and stock performance since the 1997 financial crisis. A macroeconomic model is used to estimate the chain effect of international trade on Asian recovery. It is found that the U.S. economy had a significant impact on the recovery of this region through close international trade relationship. Two major factors appear to explain the recent rapid recovery: (1) strong U.S. economic growth and currency value, and (2) the current account surplus and net inflow in foreign direct investment of crisis-hit countries.

The purpose of this study was to investigate an effective recovery method on muscle function and blood of lactate level after maximal isotonic exercise. This study was conducted in 36 adult males. The group was divided into three groups. Sling therapy group (SG, $n=12$), sling therapy group with whole body vibration continuous (SAVG, $n=12$) and sling therapy group with whole body vibration in intermittent (SIVG, $n=12$) were randomly composed. Sling exercise therapy using supine position and whole-body vibration of 10Hz, 5mm were performed. Lactate level and muscle function during the rest, fatigue and recovery period were measured and then maximal exercise using back extension was performed to induce fatigue. After 15min, sling with whole body vibration was conducted in two groups, respectively. Blood lactate was measured a few hours before and after of vibration. Also, muscle function between only sling exercise therapy condition, sling with whole body vibration condition in all time and sling with whole body vibration condition in intermittent time were analyzed. Lactate level was recorded by lactate measurement device. Isokinetic of lumber joint extension and flexion Peak torque/body weight, total work (J), average power (W) and acceleration time (m/s²) were measured using isokinetic dynamometer. The recovery method of sling with whole body vibration showed positive changes in physical characteristics. Isokinetic contraction of peak torque/body weight (N$\cdot$m), average power (Watts) and total work (J) were significantly increased in the recovery step for SIVG. Lactate level was significantly decreased for SIVG as compared with SG and SAVG. This study demonstrated that sling exercise therapy with intermittent time whole body vibration could provide a positive effect on the efficient recovery of muscle function and higher reduction of lactate after maximal isotonic exercise.

This study aimed to systematically evaluate the effectiveness of Baduanjin in the treatment of lumbar disc herniation (LDH). We searched PubMed, the Cochrane Library, EMBASE, Web of Science (WOS), CNKI, and Wanfang Databases from their inception until August 1, 2021, to collect the randomized controlled trials (RCTs) of Baduanjin in the treatment of LDH. After literature screening, data extraction, and quality evaluation by two independent researchers, the RevMan 5.4 software was used for meta-analysis. A total of 13 studies, involving 853 patients were finally included. The results showed that compared with the control group, the Baduanjin group showed remarkably improved treatment efficiency ($\mathrm{\text{RR}}=1.14$, 95% CI (1.05, 1.23), $P=0.001$), JOA score ($\mathrm{\text{MD}}=2.62$, 95% CI (0.56, 4.68), $P=0.01$), and VAS score ($\mathrm{\text{MD}}=-0.87$, 95% CI ($-1.14$, $-0.60$), $P<0.00001$). The Baduanjin group exhibited higher VAS scores than the control group in different intervention times (within 1 month, 1–2 months, and more than two months) ($P<0.05$). Moreover, the JOA score of the Baduanjin was better than that of the control group in the presence of intervention for more than two months ($\mathrm{\text{MD}}=4.17$, 95% CI (1.05, 7.30), $P=0.009$). In the comparison of exercise therapy, Baduanjin has more advantages than traditional rehabilitation training, as manifested by the improved VAS score ($\mathrm{\text{MD}}=-0.60$, 95% CI ($-0.83$, $-0.36$), $P<0.00001$) and JOA score ($\mathrm{\text{MD}}=2.63$, 95% CI (1.63, 3.09), $P<0.00001$). Conclusion: Baduanjin can significantly improve the rehabilitation evaluation scores of LDH patients and the treatment efficiency, and its curative effect was more obvious in a long time.

Stress is a pervasive phenomenon with significant implications for individual well-being. Understanding the neural processes underlying stress responses and recovery is crucial for developing effective interventions. This study employed functional magnetic resonance imaging (fMRI) to investigate the brain activation patterns during stress induction and recovery in healthy adults. The Montreal Imaging Stress Task (MIST) was utilized to elicit acute stress in participants. The results revealed that during the stress task phase, the right hemisphere showed activation in the Inferior Parietal Lobule, Postcentral Gyrus, and Precuneus, while the left hemisphere demonstrated activation in the Inferior Parietal Lobule, Postcentral Gyrus, Middle Frontal Gyrus, and Superior Frontal Gyrus. Following the stress task, during the recovery phase, the right hemisphere exhibited activation in the Precuneus, Middle Occipital Gyrus, Superior Occipital Gyrus, Angular Gyrus, Medial Frontal Gyrus, Middle Frontal Gyrus, and Posterior Cingulate, whereas the left hemisphere displayed activation primarily in the Cuneus. Comparing the two phases, the left frontal lobe and occipital lobe exhibited increased activation during the rest period after stress. In contrast, the parietal lobe showed decreased activation during the recovery phase. These findings contribute to our understanding of the neural mechanisms associated with stress responses and recovery, providing insights into potential interventions for stress management and promoting well-being.

Recovery of society after a large-scale disaster generally consists of two phases, short- and long-term recoveries. The main goal of the short-term recovery is to bounce the damaged system back to the operating standards enabling residents in damaged cities to survive, and fast supply with vital resources to them is one of its important elements. We propose a general principle by which the required redistribution of vital resources between the affected and neighboring cities can be efficiently implemented. The short-term recovery is a rescuer operation where uncertainty in evaluating the state of damaged region is highly probable. To allow for such an operation, the developed principle involves two basic components. The first one of ethic nature is the triage concept determining the current city priority in the resource delivery. The second one is the minimization of the delivery time subjected to this priority. Finally a certain plan of the resource redistribution is generated according to this principle. Several specific examples are studied numerically. It elucidates, in particular, the effects of system characteristics such as the city limit capacity in resource delivery, the type of initial resource allocation among the cities, the number of cities able to participate in the resource redistribution, and the damage level in the affected cities. As far as the uncertainty in evaluating the state of damaged region is concerned, some specific cases were studied. It assumes the initial communication system has crashed and formation of a new one and the resource redistribution proceed synchronously. The obtained results enable us to consider the resource redistribution plan governed by the proposed method semi-optimal and rather efficient especially under uncertainty.

This paper reviews the problems that many electronics manufacturers are facing in a society of rules and regulations that are becoming increasingly environmentally conscious. The effect of electronics assembly, disassembly, and disposal on the environment is reviewed, and the potential hazards of continuing the present trends in electronics parts disposal is discussed. The paper contains a comprehensive survey of previous works related to environmentally conscious manufacturing practices, recycling, and the complexities of disassembly in the electronics industry. Interest in this area has intensified in recent years due to an increased awareness of the problem in a world of high technology where electronic products dominate. Industrial applications of recycling programs are presented and existing methodologies and evaluation systems are discussed. In order to promote and support this new environmental ethic in electronics assembly and disassembly, the need for improved methods of electronics reuse, minimization of life-cycle scrap, development of planning tools, and an increase in research activity in this area are also highlighted.

In recent years, markets have been hit by various crises, both economically and naturally. These shocks have highlighted how important it is for companies to be able to adapt with resilient behaviors. Entrepreneurs and their resilience capacity will play a very important role in the recovery process. Resilience is closely linked to other abilities such as risk intelligence; that is, the ability to look at uncertainty as an opportunity rather than a disadvantage or danger. The study assesses the relationship between these two constructs using a sample of entrepreneurs in the tourism sector within Italy. Analysis confirmed a relationship between subjective risk intelligence and resilience. These relations are explained by taking into consideration four aspects (imaginative capacity, problem-solving self-efficacy, attitude toward uncertainty and emotional stress management) included in risk intelligence, highlighting which of them contributed to explaining the three dimensions of the resilience construct (hardiness, resourcefulness and optimism).

Increasing population and individual wealth have led to a higher demand for energy and raw material resources as well as for steady improvement of processing technology in view of efficient use of resources and avoiding emissions in production and recycling processes. Present situation and future trend of recycling processing are discussed by examples from the aluminium and steel industries, recycling of cars and post-consumer municipal recovery. The importance of more intense observance of thermodynamic laws and of a 4E strategy "Economy, Energy, Environment and Education" is outlined.

To describe the viscoplastic behavior of materials under cyclic loading, a dislocation density-based constitutive model is developed based on the unified constitutive theory in which both the creep and plastic strain are integrated into an inelastic strain tensor. The stress evolution during cyclic deformation is caused by the mutual competition and interaction between hardening and recovery. To incorporate the physical mechanisms of cyclic deformation, the change of mobile dislocation density is associated with inelastic stain in the proposed model. The evolution of immobile dislocation density induced by strain hardening, dynamic recovery, static recovery and strain-induced recovery are simulated separately. The deterioration of yield strength following the hardening in tension (or compression) and subsequently in compression (or tension) is described by the Bauschinger effect and reduction of immobile dislocation density, the latter is induced by static- and strain-induced recovery. A kinematic hardening law based on dislocation density is proposed, both isotropic hardening and softening are described by determining the evolution of hardening parameters. The experimental data of P91 steel under different strain rates and temperatures are adopted to verify the proposed model. In general, the numerical predictions agree well with the experimental results. It is demonstrated that the developed model can accurately describe the hardening rate change, the yield strength deterioration and the softening under cyclic loading.