Successful Switch Research Articles

P93-8 Successful switch to cisplatin-based therapy in a NSCLC patient developing carboplatin-induced hypersensitivity reaction

P93-8 Successful switch to cisplatin-based therapy in a NSCLC patient developing carboplatin-induced hypersensitivity reaction

User-dedicated optical path switching with optical-wireless cooperative control for low-latency and seamless handover

We propose a user-dedicated optical path switching technique for low-latency and seamless handover in the radio access network (RAN) with the all-photonic network (APN). The APN is a network that connects end points directly with optical paths of dedicated wavelengths assigned to each user and provides large-capacity and low-latency connections. As mobile systems beyond 5th generation (5G) and 6th generation (6G) will require extremely low latency, applying the APN to the RAN is promising to achieve this. However, the RAN with the APN has a challenge in optical path switching during the handover procedure of mobile systems because optical switches that compose the APN do not have an Internet protocol (IP) layer function that enables routing control for handover in the conventional router network. Our proposed optical path switching technique to solve this challenge utilizes optical-wireless cooperative control and switches an optical path dedicated to user equipment (UE) executing handover in conjunction with its handover procedure. The key point of the proposed technique is that a next generation node B (gNB) transmits an optimal-timing optical path switching trigger to the optical switch. We experimentally demonstrated the generation of a dedicated optical path for UE in the RAN with the APN as a premise to enable the proposed optical path switching technique. To evaluate the feasibility and effectiveness of the proposed optical path switching technique, we experimentally compared the optical switch and router in terms of latency performance, packet loss, and packet misdirection in the path switching during handover. The results indicated successful optical path switching during handover without packet loss and packet misdirection while reducing the latency per single network equipment by 99%, from 4 µs for the router to 45 ns for the optical switch.

Optimal level of human intracranial theta activity for behavioral switching in the subthalamo-medio-prefrontal circuit

The ability to switch between rules associating stimuli and responses depend on a circuit including the dorsomedial prefrontal cortex (dmPFC) and the subthalamic nucleus (STN). However, the precise neural implementations of switching remain unclear. To address this issue, we recorded local field potentials from the STN and from the dmPFC of neuropsychiatric patients during behavioral switching. Drift-diffusion modeling revealed that switching is associated with a shift in the starting point of evidence accumulation. Theta activity increases in dmPFC and STN during successful switch trials, while temporally delayed and excessive levels of theta lead to premature switch errors. This seemingly opposing impact of increased theta in successful and unsuccessful switching is explained by a negative correlation between theta activity and the starting point. Together, these results shed a new light on the neural mechanisms underlying the rapid reconfiguration of stimulus-response associations, revealing a Goldilocks’ effect of theta activity on switching behavior.

Dielectric Transition-Instigated Extraordinary Capacitance Change with Successive Switching in Loss Tangent at the Spin Transition Temperatures of a Spin-Crossover Nanomaterial

Dielectric Transition-Instigated Extraordinary Capacitance Change with Successive Switching in Loss Tangent at the Spin Transition Temperatures of a Spin-Crossover Nanomaterial

Evaluation of prescribing patterns of switching to and add-on lemborexant in patients treated with hypnotic medication: a nationwide claims database study in Japan

ABSTRACT Background When considering changing hypnotic pharmacotherapy, lemborexant has attracted attention as a candidate due to its effectiveness and safety profile. However, few studies have investigated switching patterns in clinical practice. Research design and methods We conducted a retrospective cohort study using a nationwide claims database. Patients prescribed a single hypnotic who either subsequently switched to (switching cohort) or were additionally prescribed (add-on cohort) lemborexant between July 2020 and December 2021 were identified. Proportion of successful switching was defined as remaining on lemborexant alone or without any hypnotic at 6 months after lemborexant initiation. Results The success proportion was 70.1% in the switching cohort (n = 4,861) and 38.6% in the add-on cohort (n = 9,423). In the add-on cohort, the success proportion was lower in patients with a hypnotic history of ≥180 days (31.4%) and in patients whose prescribed hypnotic was a benzodiazepine or non-benzodiazepine (31.5% and 37.6%, respectively). Conclusion The proportion of successful switching was higher in patients who switched to lemborexant than in those who added lemborexant as a concomitant treatment. The lower success proportion in the add-on cohort might be related to clinically more severe insomnia, and/or a concomitant prescription of benzodiazepine or non-benzodiazepine, from which discontinuation may be challenging.

Real-life evaluation of NIV to CPAP switch in patients with chronic respiratory failure. A case control study

BackgroundNon-invasive ventilation (NIV) is a standard of care for hypercapnic chronic respiratory failure (CRF). Obstructive sleep apnea syndrome (OSA) frequently contributes to hypoventilation in CRF patients. CPAP improves hypercapnia in selected COPD and obese patients, like NIV. We aimed to describe the profile of patients switching from NIV to CPAP in a cohort of patients on long-term ventilation and to identify the factors associated with a successful switch. MethodsIn this case-control study, 88 consecutive patients who were candidates for a NIV-CPAP switch were compared with 266 controls among 394 ventilated patients treated at the Dijon University Hospital between 2015 and 2020. They followed a standardized protocol including a poly(somno)graphy recorded after NIV withdrawal for three nights. CPAP trial was performed if severe OSA was confirmed. Patients were checked for recurrent hypoventilation after 1 and 23[14–46] nights under CPAP. ResultsPatients were 53% males, median age 65 [56–74] years, and median BMI 34 [25–38.5] kg/m2. Sixty four percent of patients were safely switched and remained on long-term CPAP. In multivariate analysis, the probability of a NIV-CPAP switch was correlated to older age (OR: 1.3 [1.01–1.06]), BMI (OR: 1.7 [1.03–1.12]), CRF etiology (OR for COPD: 20.37 [4.2–98,72], OR for obesity: 7.31 [1.58–33.74]), circumstances of NIV initiation (OR for acute exacerbation: 11.64 [2.03–66.62]), lower pressure support (OR: 0.90 [0.73–0.92]), lower baseline PaCO2 (OR: 0.85 [0.80–0.91]) and lower compliance (OR: 0.76 [0.64–0.90]). Among 72 patients who went home under CPAP, pressure support level was the only factor associated with the outcome of the NIV-CPAP switch, even after adjustment for BMI and age (p=0.01) with a non-linear correlation. Etiology of chronic respiratory failure, age, BMI, baseline PaCO2, circumstances of NIV initiation, time under home NIV or NIV compliance were not predictive of the outcome of the NIV-CPAP switch. ConclusionsA NIV-CPAP switch is possible in real life conditions in stable obese and COPD patients with underlying OSA.

Severe hypoalbuminemia complicating a successful atrial switch operation (Senning) with cardiopulmonary bypass - report on a rare case

Post-operative hypoalbuminemia has been reported in 12% of neonates and 20% of infants; 97% occurs in the first 48 hours in neonates and infants undergoing cardiac surgery with cardiopulmonary bypass (CPB). Perioperative hypoalbuminemia is not independently associated with any post-operative morbidity. However, when analysed as a continuous variable, lower serum albumin levels have been reported to be associated with increased post-operative morbidity. Pre-operative low serum albumin level is independently associated with increased odds of post-operative hypoalbuminemia, and prolonged length of hospital stay. Immediate post-CPB (0-24 hour), lower serum albumin level is independently associated with an increased duration of mechanical ventilation. There is a relative paucity of literature on the impact of hypoalbuminemia in the paediatric population. Hypoalbuminemia is a marker of poor outcome in critically ill children and those undergoing a wide range of medical interventions. Albumin infusions may be an effective therapy for fluid resuscitation and for patients with severe hypoalbuminemia. We present a successful perioperative management of a 3 months old-male child, weighing 3.5 kg with dextro-transposition of great arteries (D-TGA) with regressed LV undergoing an atrial switch (Senning) procedure, and uneventful intraoperative course i.e. easy weaning from CPB. However, in the ICU, the baby suffered an unusual complication as severe hypoproteinaemia resulting in acute kidney injury (AKI) with complete anuria, generalized anasarca, hypotension requiring inotropes and vasopressors, and difficult weaning from ventilator.

Decreased clinical performance in TGA-ASO patients after RVOT interventions; a multicenter European collaboration

BackgroundIn patients with transposition of the great arteries and an arterial switch operation (TGA-ASO) right ventricular outflow tract (RVOT) obstruction is a common complication requiring one or more RVOT interventions. ObjectivesWe aimed to assess cardiopulmonary exercise capacity and right ventricular function in patients stratified for type of RVOT intervention. MethodsTGA-ASO patients (≥16 years) were stratified by type of RVOT intervention. The following outcome parameters were included: predicted (%) peak oxygen uptake (peak VO2), tricuspid annular plane systolic excursion (TAPSE), tricuspid Lateral Annular Systolic Velocity (TV S′), right ventricle (RV)-arterial coupling (defined as TAPSE/RV systolic pressure ratio), and N-terminal proBNP (NT-proBNP). Results447 TGA patients with a mean age of 25.0 (interquartile range (IQR) 21–29) years were included. Patients without previous RVOT intervention (n = 338, 76%) had a significantly higher predicted peak VO2 (78.0 ± 17.4%) compared to patients with single approach catheter-based RVOT intervention (73.7 ± 12.7%), single approach surgical RVOT intervention (73.8 ± 28.1%), and patients with multiple approach RVOT intervention (66.2 ± 14.0%, p = 0.021). RV-arterial coupling was found to be significantly lower in patients with prior catheter-based and/or surgical RVOT intervention compared to patients without any RVOT intervention (p = 0.029). ConclusionsTGA patients after a successful arterial switch repair have a decreased exercise capacity. A considerable amount of TGA patients with either catheter or surgical RVOT intervention perform significantly worse compared to patients without RVOT interventions.

10 kHz stimulation as rescue therapy for spinal cord stimulation trial failure or loss of efficacy: A retrospective study.

Spinal cord stimulation (SCS) is currently used for the management of pain of different origin, and since its inception, many waveforms have been developed. Some patients experience no pain relief already during SCS trial, while other patients go through a loss of efficacy due to habituation after a variable period of satisfying pain control. Our retrospective study represents the first report exploring the potential role of 10 kHz stimulation as rescue therapy for patients who did not benefit not only from conventional stimulation but even from other waveforms during SCS trial or follow-up. This study was conducted in Germany; we retrospectively enrolled patients with no pain relief during SCS trial or with loss of efficacy of other waveforms over time; and we recorded visual analogic scale (VAS), Oswestry Disability Index (ODI), and daily opioid consumption expressed as morphine milligram equivalents (MME), right before and 12 months after the switching to 10 kHz simulation. The rate of successful switching to 10 kHz stimulation was comparable in patients enrolled during the SCS trial and during the follow-up (43% vs. 40%, respectively); notably, the highest rate of failed rescue was recorded in case of persistent spinal pain syndrome (PSPS) II. Patients who responded to the switching showed a significant improvement in VAS and ODI after 12 months of treatment compared to baseline (3.6 ± 1.0 vs. 8.2 ± 0.9, p < 0.00001 and 34.0 ± 7.8 vs. 64.3 ± 8.7, p < 0.0001, respectively), whereas there was no reduction in the consumption of opioids in terms of MME (3 (0-16) vs. 5 (0-8.75), p = 0.1003). Rescue therapy with 10 kHz stimulation could be an important strategy to avoid SCS explant in both patients non-responsive during trial or experiencing a loss of efficacy during the years with other waveforms.

Dual Mode Optoelectronic Devices Based on 2D Single Crystalline VO2 Films with Controlled Metallic Domain Regime Induced Variable Hysteresis

AbstractThe multimode optoelectronic operation in a single component device is an attractive design strategy for future optoelectronics, which demands unique and complex multifunction. Here, a novel dual‐mode optoelectronic device with both memory and switching functionalities by utilizing alternating metallic stripe domain regime‐induced controllable hysteresis of two dimensional (2D)‐crystalline VO2 films is reported. It is found that the formation and disappearance of tensile strain‐induced metallic stripe domain arrays are susceptible to temperature‐induced thermal energy, allowing controllable hysteresis in electric field‐induced metal‐insulator transition (E‐MIT) by tuning the total region of aligned metallic stripe domains within the VO2 films through current flow‐induced thermal energy. Based on the tunable hysteresis in E‐MIT, the 2D‐crystalline VO2 film‐based device exhibits successful multimode optoelectronic memory and switching operations. The device with a large hysteresis width exhibits high‐performance optoelectronic memory behavior with a high on/off ratio of up to ≈55% and a long retention time over 5000 s response to a light pulse optically triggering MIT. On the other hand, the 2D‐crystalline VO2 film device with a narrow hysteresis width exhibits high performance of photodetection with a responsivity of 316 mA W−1 and response times of ≈1.2 and ≈2 µs at rise and fall, respectively.

Switching attack modeling and vulnerability analysis of generator for dynamics study

This paper presents novel insights about cyber-attacks in the power network and their consequence in terms of stability. Compared to existing cyber-attack related studies in power systems, the work discusses switching attack construction and evaluates the impact on generator dynamics. As such, the study is in two folds: (i) switching attack construction, with selection of switching instants based on system states and (ii) vulnerability analysis of power system components, circuit breaker, governor system and excitation system of generators. The role of inherently present communication delay/state variable delay becomes important as it has direct impact on dynamic performance of the system. The impact of the constant and timedependent delay on the stability is addressed by determining the time-delay margin using Lyapunov-Krasovskii functional. Thereafter, the condition for successful switching attack construction is given in terms of delay margin. The accuracy of the derived condition for successful switching attack is demonstrated via real-time co-simulation (RTDS) and MATLAB software. The vulnerability of power system components in IEEE 3-machine, 9-bus network are analysed as individuals or their combinations when subjected to switching attacks. The adequacy related to power system stability as a consequence of cyber-attacks is investigated with an estimation of RoCoF of generators.

Successful Treatment with Ramucirumab Plus Erlotinib following Osimertinib-induced Interstitial Lung Disease: A Case Report.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are key drugs for patients with EGFR mutation-positive non-small-cell lung cancer, and osimertinib is the standard treatment. Although drug-induced interstitial lung disease (ILD) is a remarkable adverse event of EGFR-TKIs, evidence regarding the continuation and re-challenge of EGFR-TKIs after drug-induced severe ILD is lacking. This is the first report of successful switching to ramucirumab plus erlotinib after osimertinib-induced severe ILD in an 81-year-old woman with stage IV lung adenocarcinoma harboring the EGFR L858R mutation in exon 21. These findings suggest that ramucirumab plus erlotinib may be a viable treatment option for osimertinib-induced severe ILD.

Residual upper airway obstruction during nocturnal noninvasive ventilation despite high positive expiratory pressure. Impact of oronasal mask to nasal mask switch

BackgroundNasal mask (NM) and oronasal masks (OM) can be used to provide noninvasive ventilation (NIV). Recent studies suggested that OM is the most used interface and that there is no difference in efficacy or in tolerance between OM and NM for chronic use. However, studies focusing on video laryngoscopy underlined the impact of OM in residual upper airway obstruction (UAO) under NIV. We sought to assess the real-life practice of switching from OM to NM when UAO events persist despite high EPAP levels. MethodsIn an open-label single center prospective cohort study, data from files and full night polysomnography on NM and OM were collected for patients wearing OM and presenting an UAO index ≥15/h despite an EPAP level ≥ 10 cmH20. ResultsForty-four patients were included in the study. In 31 patients (74 %), switching to a NM reduced UAOi to ≥10/h. Interestingly, 92 % of these patients still had NM at 3 to 12 months of follow-up. Switching to a NM was also associated with a trend in paCO2 reduction and significant improvements in Epworth, sleep quality and NIV compliance. Successful interface switching was significantly associated with female gender, and a trend was observed in non-smokers. ConclusionAs for CPAP, switching to a NM improved NIV efficacy in a selected group of patients presenting residual UAO events despite high EPAP levels. Additionally, this switch has an impact on compliance and subjective sleepiness. Thus, in patients with persisting UAO on OM, switching to a NM could be a first-line intervention before considering further investigation such as polygraphy or video laryngoscopy. We also derive an algorithm for mask allocation and adaptation in acute and chronic NIV use.

Switching checkerboards in (0,1)-matrices

In order to study M(R,C), the set of binary matrices with fixed row and column sums R and C, we consider submatrices of the form (1001) and (0110), called positive and negative checkerboard respectively. We define an oriented graph of matrices G(R,C) with vertex set M(R,C) and an arc from A to A′ indicates you can reach A′ by switching a negative checkerboard in A to positive. We show that G(R,C) is a directed acyclic graph and identify classes of matrices which constitute unique sinks and sources of G(R,C). Given A,A′∈M(R,C), we give necessary conditions and sufficient conditions on M=A′−A for the existence of a directed path from A to A′.We then consider the special case of M(D), the set of adjacency matrices of graphs with fixed degree distribution D. We define G(D) accordingly by switching negative checkerboards in symmetric pairs. We show that Z2, an approximation of the spectral radius λ1 based on the second Zagreb index, is non-decreasing along arcs of G(D). Also, λ1 reaches its maximum in M(D) at a sink of G(D). We provide simulation results showing that applying successive positive switches to an Erdős-Rényi graph can significantly increase λ1.

Impact-Ionization Switching of High-Voltage Thyristors Connected in Parallel

Thyristors triggered in the impact-ionization wave mode is a promising switching method in pulsed power technology. This triggering approach enhances the current capability of standard thyristors, allowing switching a current pulse with an amplitude of 200 kA and a current rise time rate-of-change (dI/dt) of 58 kA/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> s. Thyristor wafer area can be considered as one of the factors that are limiting the peak current amplitude and dI/dt. Switching thyristors in parallel is a possible solution to overcome these limitations. However, no evidence was found in the literature for successful parallel switching of standard thyristors in the impact-ionization wave mode. In this research, the possibility of parallel switching of two standard thyristors rated for 2.2 kV with a wafer diameter of 32 mm was investigated. A Marx generator equipped with a peaking module was used to charge the thyristor equivalent capacitance (1 nF) up to double its static breakdown voltage with a voltage rise time rate-of-change (dV/dt) of more than 1 kV/ns, as required for impact-ionization triggering. The diagnostic system includes two wideband voltage probes (VPs) with a subnanosecond time response, which allows simultaneous measurement of a voltage drop across each thyristor connected in parallel. Two stages of thyristor operation were investigated: 1) a triggering stage, without energy switching, when a dc bias voltage is applied; and 2) a current flow stage, with energy switching, when an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$RLC$</tex-math> </inline-formula> discharge circuit is connected. In these experiments, thyristors change from blocking to conducting state within 400 ps, switching a current pulse with an amplitude of 11 kA and a dI/dt of 6 kA/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> s (circuit limits). The current imbalance between the thyristors was less than 10%. To the best of the authors’ knowledge, it is the first time reported that high-voltage thyristors connected in parallel have been successfully triggered in the impact-ionization wave mode.

Successful switching from mepolizumab to dupilumab in a patient with EGPA in remission phase and persistent nasal polyposis.

Successful switching from mepolizumab to dupilumab in a patient with EGPA in remission phase and persistent nasal polyposis.

Gamma-Aminobutyric Acid and Glutamate Concentrations in the Striatum and Anterior Cingulate Cortex Not Found to Be Associated with Cognitive Flexibility.

Behavioral flexibility and goal-directed behavior heavily depend on fronto-striatal networks. Within these circuits, gamma-aminobutyric acid (GABA) and glutamate play an important role in (motor) response inhibition, but it has remained largely unclear whether they are also relevant for cognitive inhibition. We hence investigated the functional role of these transmitters for cognitive inhibition during cognitive flexibility. Healthy young adults performed two paradigms assessing different aspects of cognitive flexibility. Magnetic resonance spectroscopy (MRS) was used to quantify GABA+ and total glutamate/glutamine (Glx) levels in the striatum and anterior cingulate cortex (ACC) referenced to N-acetylaspartate (NAA). We observed typical task switching and backward inhibition effects, but striatal and ACC concentrations of GABA+/NAA and Glx/NAA were not associated with cognitive flexibility in a functionally relevant manner. The assumption of null effects was underpinned by Bayesian testing. These findings suggest that behavioral and cognitive inhibition are functionally distinct faculties, that depend on (at least partly) different brain structures and neurotransmitter systems. While previous studies consistently demonstrated that motor response inhibition is modulated by ACC and striatal GABA levels, our results suggest that the functionally distinct cognitive inhibition required for successful switching is not, or at least to a much lesser degree, modulated by these factors.

Small-volume tubes to reduce anemia and transfusion (STRATUS): a pilot study.

Blood sampling for diagnostic testing causes blood loss. Small-volume tubes have the same cost, dimensions, and blood-draw techniques as standard-volume tubes, and are compatible with laboratory equipment; however, they are not commonly used. We sought to assess the feasibility of a stepped-wedge cluster trial to determine whether small-volume tubes reduce transfusion compared with standard-volume tubes in intensive care unit (ICU) patients. We conducted a prospective mixed-methods pilot study (before-after design) in one ICU with a six-week control period (standard-volume tubes) and a six-week intervention period (small-volume tubes). All patients admitted to the ICU were included. Feasibility was assessed as successful switch to small-volume tubes; adherence to tube size; sufficient volume for testing; user acceptance; barriers and facilitators to implementation; and 95% transfusion collection. We explored end-user acceptability using focus groups. One hundred and sixty-five patients were included in the standard-volume and 204 in the small-volume periods. Transition to small-volume tubes was successful. Random audits showed 100% compliance. The proportion of samples with inadequate volume for testing was the same for both groups (both, 0.2%). Based on ten focus groups, small-volume tubes were acceptable with no barriers identified. Transfusion data collection was 100%. Median [interquartile range] estimated blood loss due to laboratory testing per patient per day in ICU was 11 [8-17] mL with standard-volume and 6 [4-8] mL with small-volume tubes. Small-volume tubes can be implemented with acceptability to end-users and without barriers. They did not result in an increased frequency of inadequate samples. These results inform a trial to determine whether small-volume tubes reduce transfusion. ClinicalTrials.gov (NCT03284944); registered 15 September 2017.

Can brexpiprazole be switched safely in patients with schizophrenia and dopamine supersensitivity psychosis? A retrospective analysis in a real-world clinical practice.

Several studies have reported that a switch to the dopamine partial agonist (DPA) aripiprazole (ARP), especially when the switch is abrupt, is likely to fail and sometimes worsen psychosis in schizophrenia patients already under high-dose antipsychotic treatment. Such a switching failure is speculated to be related to be the dopamine supersensitivity state. The risks of switching to the DPA brexpiprazole (BREX) have not been reported. We retrospectively analyzed the cases of 106 patients with schizophrenia to identify any factors related to the success or failure of switching to BREX. The comparison between the patients with dopamine supersensitivity psychosis (n = 44) and those without (n = 62) revealed no significant difference in the switching failure judged at the sixth week. A comparison of the patients with successful switching (n = 80) and those who failed (n = 26) revealed that patients with treatment-resistant schizophrenia (TRS) were significantly more likely to fail. A logistic regression analysis also revealed that patients with past failure of switching to ARP are likely to succeed in switching to BREX. The 2-year follow-up of the patients with successful switching to BREX suggested that the patients who were treated with BREX, even temporarily, experienced some improvement in their Global Assessment of Functioning and Clinical Global Impression-Severity scores. Overall, the results indicate that patients with schizophrenia can be switched more safely to BREX compared to ARP. However, the failure of switching to BREX could be higher in patients with TRS, and thus, starting BREX treatment in refractory patients warrants careful monitoring.

Resource-efficient protection scheme for optical service units in fifth-generation fixed networks

One of the visions of fifth-generation fixed networks (F5G) is to provide a guaranteed reliable experience (GRE). Optical transport networks (OTNs) represent a primary candidate technology to offer high-quality bandwidth in F5G and hence to support GRE. Unfortunately, current OTN technologies provide large-bandwidth tunnels for carrying aggregated (typically, Ethernet) traffic, and corresponding protection techniques in OTNs consume a lot of resources. The emergence of a new technology called an optical service unit (OSU), which subdivides the payload block of traditional optical data units into smaller units, allows for the development of more flexible and resource-efficient protection schemes. In this paper, we propose a new resource-efficient protection scheme for OSU-based OTNs called OSU protection (OSU-P), with the aim to save network resources while providing individual customized protection for each single user. OSU-P only reserves small-bandwidth protection/backup connections for protected services; then, when a failure occurs, the protection bandwidth is adjusted to the bandwidth required by the service during the switching process. This scheme can save a significant amount of network resources, but it may encounter resource conflicts between the protected services and other preemptable services after a failure occurs. Hence, we also propose a deterministic protection algorithm and a preemptable service provisioning algorithm based on overlapping risk avoidance, which can ensure successful recovery switching of protected services and the least impact on preemptable unprotected services after a network failure occurs. Simulation results show that, compared with traditional 1+1 and 1:1 protection schemes, OSU-P can reduce spare resources allocated for protection by about 30% and 11%, respectively, and reduce the blocking rate by about 27% and 10%, respectively. The performance of the proposed algorithms in terms of the percentage of unsuccessful protection and affected preemptable services is also verified.