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高分级动脉瘤性蛛网膜下腔出血（poor grade aneurysmal subarachnoid hemorrage，PaSAH）患者易在发病后迅速出现意识障碍、颅内压增高以及高热等危重症状，其死亡率和致残率均很高。诸多证据表明，目标温度管理（target temperature management，TTM）可以改善心搏骤停后导致的脑损伤等疾病的预后。然而，PaSAH患者能否进行TTM仍存在争议。本文对TTM的适应证和禁忌证、多模态监测方式与前景、应用的结果、诱导方式、实施方案和不良反应的相关研究进行综述，以期为TTM应用于PaSAH提供一定的参考依据。 Abstract: Patients with poor grade aneurysmal subarachnoid hemorrhage (PaSAH) are prone to rapid onset of critical symptoms such as consciousness disorder, increased intracranial pressure, and hyperthermia, which are associated with high rates of mortality and disability. Numerous evidences have shown that target temperature management (TTM) can improve the prognosis of diseases such as brain damage caused after cardiac arrest. However, whether TTM can be performed in PaSAH patients remains controversial. In this paper, indications and contraindications in PaSAH patients, multimodal monitoring modalities and prospects, outcomes of application, induction modalities, implementation protocols and adverse reactions were reviewed, with a view to providing some reference for the application of TTM in PaSAH.

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Changdong Wu,* Ping Wang,* Bin Wang, Muyesai Nijiati, Ming Hou Xinjiang Emergency Center, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, 830001, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ming Hou, Xinjiang Emergency Center, People’s Hospital of Xinjiang Uygur Autonomous Region, No. 91, Tian-chi Road, Tianshan District, Urumqi, 830001, People’s Republic of China, Tel +86-9918563596, Email houming199@sina.comPurpose: To investigate the optimal target temperature of cooling intervention in heat stroke (HS) rats and explore the potential mechanisms of cooling intervention in alleviating heat stroke-induced damage.Materials and Methods: A total of 32 Sprague-Dawley rats were randomly divided into 4 groups (n=8/group), including control, HS[core body temperature (Tc)], HS(Tc-1°C) and HS(Tc+1°C) group. Heat stroke model was established in rats of HS(Tc), HS(Tc-1°C) and HS(Tc+1°C) group. Rats in HS(Tc) group were cooled to baseline core body temperature after establishing heat stroke model, HS(Tc-1°C) group to baseline core body temperature minus 1°C and HS(Tc+1°C) group to baseline core body temperature plus 1°C. We compared the histopathological changes of lung, liver and renal tissue, as well as cell apoptosis and expression of critical proteins in phosphatidylinositol 3´-kinase (PI3K)/Akt signaling pathway.Results: Heat stroke caused the histopathological damage and cell apoptosis of lung, liver and renal tissue, which could be alleviated by cooling intervention to a certain extent. Notably, HS(Tc+1°C) group demonstrated a better effect on alleviating cell apoptosis although the differences were not significant. Heat stroke lead to the elevated expression of p-Akt, which subsequently induced the elevated expression of Caspase-3 and Bax, as well as the decreased expression of Bcl-2. Cooling intervention could reverse this trend. Notably, the expression level of Bax in lung tissue of HS(Tc+1°C) group was significantly lower than that of HS(Tc) and HS(Tc-1°C) group.Conclusion: The mechanisms of cooling intervention in alleviating heat stroke-induced damage were associated with the expression changes of p-Akt, Caspase-3, Bax and Bcl-2. The better effect of Tc+1°C might be associated with low expression of Bax.Keywords: heat stroke, cooling intervention, target temperature, histopathological damage, cell apoptosis, PI3K/Akt signaling pathway

In this work, the direct current (DC) hot magnetron sputtering (HMS) of Nb has been studied and compared with the conventional cold magnetron sputtering (CMS) discharge. Particularly, these two magnetron systems were investigated in terms of currentâ€"voltage trends, behaviour of spectral lines, target temperature, and deposition rate. The currentâ€"voltage evolution showing strong variations over time in the HMS system was used to monitor the moment when thermionic emission becomes considerable. Meanwhile, thanks to the time-resolved optical emission spectroscopy (OES), the dynamics of plasma particles and the population of their electronic levels were analysed as a function of the target temperature. The target temperature was measured owing to both pyrometry and OES-based approach, i.e. by fitting an emission spectrum baseline. Finally, in the HMS configuration used in this work, the deposition rate up to 100 nm minâˆ'1 was obtained at the applied power density of 30 W cmâˆ'2, which is three times higher than the maximum power density applicable to the classical CMS system. However, with further increase in the power density, the deposition rate values were found to be saturated, which is likely caused by a significant increment in a number of thermal electrons in the discharge area. [ABSTRACT FROM AUTHOR]

PURPOSE: To study the impact of target geometrical and linac operational parameters, such as target material and thickness, electron beam size, repetition rate, and mean current on the ability of the radiotherapy treatment head to deliver high-dose-rate x-ray irradiation in the context of novel linear accelerators capable of higher repetition rates/duty cycle than conventional clinical linacs. METHODS: The depth dose in a water phantom without a flattening filter and heat deposition in an x-ray target by 10 MeV pulsed electron beams were calculated using the Monte-Carlo code MCNPX, and the transient temperature behavior of the target was simulated by ANSYS. Several parameters that affect both the dose distribution and temperature behavior were investigated. The target was tungsten with a thickness ranging from 0 to 3 mm and a copper heat remover layer. An electron beam with full width at half maximum (FWHM) between 0 and3 mm and mean current of 0.05-2 mA was used as the primary beam at repetition rates of 100, 200, 400, and 800 Hz. RESULTS: For a 10 MeV electron beam with FWHM of 1 mm, pulse length of 5 μs, by using a thin tungsten target with thickness of 0.2 mm instead of 1 mm, and by employing a high repetition rate of 800 Hz instead of 100 Hz, the maximum dose rate delivered can increase two times from 0.57 to 1.16 Gy/s. In this simple model, the limiting factor on dose rate is the copper heat removers softening temperature, which was considered to be 500°C in our study. CONCLUSIONS: A high dose rate can be obtained by employing thin targets together with high repetition rate electron beams enabled by novel linac designs, whereas the benefit of thin targets is marginal at conventional repetition rates. Next generation linacs used to increase dose rate need different target designs compared to conventional linacs.

Summary: The high nutritional and functional value of fruits justifies the use of freeze‐drying to obtain high value‐added products. As to identify in‐line the drying end point, the usefulness of temperature evolution of a grapefruit puree, added or not with gum Arabic and bamboo fibre, when applying 20 or 40 ºC as shelf temperature has been investigated. The obtained results point for the monitoring of the product's heating rate as to identify the end of sublimation in the sample, coinciding with the time this rate starts to decrease. On the other hand, the end point of the drying step of the freeze‐drying process, optimised in terms of duration, is proposed to be related to the sample reaching a certain target temperature which does not necessarily match with the temperature of the chamber. In the concrete conditions of this study, it seems to be between 20 and 40 ºC. As for the variables considered, the biopolymers added to the grapefruit puree did not affect the duration of the process and to increase the freeze‐drier shelves temperature made it possible to reduce processing time by 40%. [ABSTRACT FROM AUTHOR]

Microwave assisted extraction (MAE) has been investigated for its potential to aid in extraction of soymilk from soybeans. A batch type grinding cum microwave heating unit was specifically designed and developed for this purpose. MAE of soymilk has resulted in significant increase (p < 0.05) in extraction yield (24%) and protein content (44.4%) as compared to conventional soymilk. Protein characteristics such as protein solubility and protein digestibility of extracted soymilk also showed significant increase (p < 0.05) with respect to conventional milk. The influence of microwave process parameters including microwave power level (540–810W), target temperature (70–90 °C) and stirring speed (140–180 RPM) on protein characteristic of soymilk were analysed. Microwave power level and target temperature were significant (p < 0.05) parameters for the extraction process. The optimal MAE conditions were power level of 675W, target temperature of 80 °C and stirring speed of 160 RPM. • Microwave assisted extraction has been proven as an effective method to increase extraction yield and quality of soymilk. • Yield, protein content and protein solubility of soymilk was increased by 24%, 44.4% and 94.6% respectively by this method. • Microwave power and target temperature were significant for yield and quality of soymilk. • SEM imaging revealed increased breakdown of soybean cell wall structure. This attributes to the success of MAE. [ABSTRACT FROM AUTHOR]

To understand and forecast biological responses to climate change, scientists frequently use field experiments that alter temperature and precipitation. Climate manipulations can manifest in complex ways, however, challenging interpretations of biological responses. We reviewed publications to compile a database of daily plot‐scale climate data from 15 active‐warming experiments. We find that the common practices of analysing treatments as mean or categorical changes (e.g. warmed vs. unwarmed) masks important variation in treatment effects over space and time. Our synthesis showed that measured mean warming, in plots with the same target warming within a study, differed by up to 1.6 ∘C (63% of target), on average, across six studies with blocked designs. Variation was high across sites and designs: for example, plots differed by 1.1 ∘C (47% of target) on average, for infrared studies with feedback control (n = 3) vs. by 2.2 ∘C (80% of target) on average for infrared with constant wattage designs (n = 2). Warming treatments produce non‐temperature effects as well, such as soil drying. The combination of these direct and indirect effects is complex and can have important biological consequences. With a case study of plant phenology across five experiments in our database, we show how accounting for drier soils with warming tripled the estimated sensitivity of budburst to temperature. We provide recommendations for future analyses, experimental design, and data sharing to improve our mechanistic understanding from climate change experiments, and thus their utility to accurately forecast species' responses. [ABSTRACT FROM AUTHOR]

Abstract The present work aims to develop the method for indirect determination of the magnetron target temperature. This method is based on the measurements of heating kinetic curves of the thermocouple sensor's sensing element. The measurements were performed during operation of the magnetrons with cold and hot titanium targets. In order to calculate the hot target temperature, a transcendental equation was derived using the Stefan-Boltzmann law and the Hertz-Knudsen equation. In the general case, the equation uses the difference of the fluxes transferred to the sensing element. The study revealed that in the target temperature range of 1000–1500 °C, the influence of the heat flux transferred by the evaporated atoms of the titanium target on the substrate temperature can be neglected. And the heat fluxes caused by the gas discharge with a current density in the range of 50–100 mA/cm2 have a significant influence on the substrate temperature. Highlights • Target temperature calculation based on substrate temperature is highly accurate. • Heat flux of the evaporated titanium target atoms negligibly impacts substrate. • At the hot target temperature of 1500 °C only thermal radiation impacts the substrate. • Substrate temperature is strongly affected by the gas discharge heat flux. [ABSTRACT FROM AUTHOR]

Body temperature (T b ) is one of the most influential factors affecting physiological processes in ectothermic animals. Reptiles use behaviours such as shuttling, and postural and orientation adjustments to ensure that T b remains close to a target. It is thought that target body temperature (T target ) is aligned to the physiological and behavioural thermal optima of the animal. The Sungazer ( Smaug giganteus ), a Threatened lizard species, is unique amongst the Cordylidae in that lizards inhabit self-excavated burrows in open grasslands, a habitat in which there are few exposed rock basking sites. In this situation, T b s are likely to be greatly influenced by postural and orientation adjustments during basking. We measured T b s using modified iButtons, and calculated T target of free-ranging Sungazers in order to assess the impact of body posture and orientation in the thermoregulation of the species. We used camera traps to record lizard behaviour at burrow entrances and aligned these measures to measures of T b . T target was 30 ± 1.4 °C, and T b s remained within this range for 371 ± 162 min per day. The anterior body-up postures resulted in faster heating and higher T b s. Lizards heated faster when facing away from the sun and spent proportionally more time in this orientation in the morning when T b s were lower than T target . Our findings suggest that their wide behavioural repertoire allows Sungazers to thermoregulate effectively over a broad range of environmental conditions and may thus be able to effectively respond to changing climatic conditions. [ABSTRACT FROM AUTHOR]

A 3D-printed metal solid target using additive manufacturing process is a cost-effective production solution to complex and intricate target design. The initial proof-of-concept prototype solid target holder was 3D-printed in cast alloy, Al⁻7Si⁻0.6Mg (A357). However, given the relatively low thermal conductivity for A357 (κmax, 160 W/m·K), replication of the solid target holder in sterling silver (SS925) with higher thermal conductivity (κmax, 361 W/m·K) was investigated. The SS925 target holder enhances the cooling efficiency of the target design, thus achieving higher target current during irradiation. A validation production of 64Cu using the 3D-printed SS925 target holder indicated no loss of enriched 64Ni from proton bombardment above 80 µA, at 11.5 MeV.

Background: Therapeutic hypothermia (TH) is a standard strategy to reduce brain damage in post-cardiac arrest syndrome (PCAS) patients. However, it is unknown whether the target temperature should be adjusted for PCAS patients in different states. Methods: Participants in the J-PULSE-Hypo study database were divided into lower (32.0-33.5 °C; Group L) or moderate (34.0-35.0 °C; Group M) temperature groups. Primary outcome was a favourable neurological outcome (proportion of patients with a Glasgow-Pittsburgh Cerebral Performance Category [CPC] of 1-2 on day 30). We compared between the two groups and in subgroups of patients divided by age and resuscitation interval (interval from collapse to return of spontaneous circulation) by propensity score (PS) analysis. Results: Overall, 467 participants were analysed. The proportions of patients with favourable neurological outcomes were as follows (Group L vs. Group M) (OR; Odds ratio): all patients, 64 % (n = 42) vs. 55 % ((n = 424) (PS; OR 1.381 (0.596-3.197)), P = 0.452) and resuscitation interval ≤ 30 min, 88 % (n = 24) vs. 64 % ((n = 281) (PS; OR 7.438 (1.769-31.272)), P = 0.007). Conclusions: PCAS patients with a resuscitation interval of <30 min may be candidates for TH with a target temperature of <34 °C. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the structure and performance of the maximum entropy temperature-emissivity separation (MaxEnTES) algorithm for assessing land temperature and emissivity from thermal infrared hyperspectral images. This procedure derives the emissivity spectrum and the temperature of the target adopting the maximum entropy (MaxEnt) estimation approach. The main advantage of the MaxEnt statistical inference is the absence of any external hypothesis, which is, instead, the main critical point characterizing any other temperature-emissivity separation (TES) algorithm. The MaxEnTES algorithm carries out the TES task adopting a modified version of the subgradient Shor's r-algorithm adopted for numerical optimization of a MaxEnt objective function. For this purpose, we have utilized the C/C++ Solvopt code from the University of Gratz to develop a practical data processing implementation. In this paper, we discuss the mathematical structure of the MaxEnTES algorithm and analyze its performance in depth using numerical simulations and remote sensing Multispectral Infrared/Visible Imaging Spectrometer images. We show that the MaxEnTES algorithm provides improved accuracy for temperature and emissivity estimation, lowering the standard estimation error to a fraction of degree Kelvin. In agreement with previous investigations, we find that the estimation accuracy grows when increasing the number of available spectral channels. The systematic errors affecting the temperature estimates (e.g., bias) are thoroughly evaluated. We prove that the MaxEnTES algorithm retrieves the correct shape of the target emissivity spectrum even in presence of a significant temperature estimation error. [ABSTRACT FROM PUBLISHER]

Brain injury is the dominant cause of death for cardiac arrest patients who are admitted to an intensive care unit, and the majority of patients die after withdrawal of life sustaining therapy (WLST) based on a presumed poor neurologic outcome. Mild induced hypothermia was found to decrease the reliability of several methods for neurological prognostication. Algorithms for prediction of outcome, that were developed before the introduction of mild hypothermia after cardiac arrest, may have affected the results of studies with hypothermia-treated patients. In previous trials on neuroprotection after cardiac arrest, including the pivotal hypothermia trials, the methods for prognostication and the reasons for WLST were not reported and may have had an effect on outcome. In the Target Temperature Management trial, in which 950 cardiac arrest patients have been randomized to treatment at 33°C or 36°C, neuroprognostication and WLST-decisions are strictly protocolized and registered. Prognostication is delayed to at least 72 hours after the end of the intervention period, thus a minimum of 4.5 days after the cardiac arrest, and is based on multiple parameters to account for the possible effects of hypothermia [ABSTRACT FROM AUTHOR]

Abstract: The method of electric preheating pipelines in the district heating system was introduced. The thermal–structural coupling analysis was used for the electric preheating insulation pipe by ANSYS. The three-dimensional transient finite element model of electric preheating pipeline in the district heating system is established according to the principle of thermology and mechanics. Through the experiment, the result obtained with experiments agrees with the finite element result. And it makes theoretical deduction and experimental analysis to electric preheating method. By analyzing energy, the current of electric preheating has been obtained. Basing on the test data of measuring current of several heating pipelines, these formulas have advantage of easy calculation, wide applications, high reliability and less error rate. [Copyright &y& Elsevier]

Abstract: Surface modification with high-power glow discharges is a promising physical vapor deposition (PVD) technology for industrial usage. A metal ion density higher than 1018 m−3 can be obtained due to a high-power input in the plasma. In the present paper, titanium films were deposited on Si (100) substrates using high-power impulse magnetron sputtering (HIPIMS). The pulse duration was varied to investigate the deposition rate and the titanium film structure. The plasma source was an unbalanced magnetron sputtering (UBMS) discharge generation system. The deposition rate was correlated to the electrical characteristics. There was an instantaneous power threshold of approximately 36 kW to significantly increase the deposition rate by 4–5 times. The deposition rate increased linearly with respect to the average power until the average power reached 5.6 kW (about 30 W/cm2 for a total area of the target), and an 83% increase of the deposition rate from the linear relationship was observed. The increase of the deposition rate was possibly closely related to the so-called thermal spike, where the target temperature increases due to a high power input to the target. The surface morphology and the crystalline structure of the films were studied for a variety of pulse durations, and the results were compared to the case of the direct-current magnetron sputtering (dcMS) process. The titanium films at an average power of 1.2 kW and a pulse duration of 50 μs have a smaller crystalline size and a smoother surface than those at an average power of 825 W by dcMS. The crystal orientation (101) was dominated when the pulse duration was lengthened to 180 μs, although the (002) orientation was dominant in dcMS. The crystal size and the surface roughness increased significantly when the pulse duration was increased from 50 μs to 180 μs in HIPIMS. The consumed power in the plasma by HIPIMS can be an important parameter for the crystal size and the structure. [Copyright &y& Elsevier]

The elemental composition and chemical states of a series of Mo nitride thin films have been investigated using x-ray photoelectron spectroscopy (XPS). The chemical composition and stoichiometry of the films were also tracked as a function of the preparative parameters: the nitrogen ion dose, ion accelerating energy and substrate temperature. At the lowest ion dose, the Mo concentration increased to a depth of ∼300 Å. The nitrogen concentration in the film decreased with increasing the ion energy. An increase in the ion energy to 100 and 200 kV led to a lower N/Mo ratio as compared to that at 50 kV. The magnitude of the binding energy separation at room temperature was smaller than that at higher temperatures. This difference might be due to the presence of B1-MoN at higher temperatures and the existence of δ-MoN at lower temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Thermal analysis was performed for a titanium drive-in target of a D–D neutron generator. Computational fluid dynamics code CFX-5 was used in this study. To define the heat flux term for the thermal analysis, beam current profile was measured. Temperature of the target was calculated at some of the operating conditions. The cooling performance of the target was evaluated by means of the comparison of the calculated maximum target temperature and the critical temperature of titanium. [Copyright &y& Elsevier]

Abstract: Thermal shock resistance is one of the most important parameters in Ultra-High Temperature Ceramics (UHTCs) since it determines their performance in various applications. In this paper, due to the fact that the material parameters of UHTCs are very sensitive to the variations of temperature, the temperature-dependent thermal shock resistance parameters of UHTCS are studied using an analytical model. The effects of target temperature on the thermal shock behavior of UHTCs thermal protection system (TPS) under active cooling are examined. The calculated results show that thermal shock behavior of the UHTCs’ TPS is strongly affected by the target temperature. [Copyright &y& Elsevier]

In this paper, the effect of the absorptivity of metal on femtosecond pulsed laser ablation is investigated. The formulas for the absorptivity depending on target temperature are derived from Maxwell Equations and the Lambert-Beer’s law. Based on this, a new two-temperature model is proposed to describe the femtosecond pulsed laser ablation with metal. Then, using Au as an example, a finite difference method is employed to simulate the space-dependent and time-dependent absorptivity and the target temperature. The temperature evolution of our model is compared with the result obtained form the heat conduction model taking the absorptivity as constant. It is shown that the absorptivity plays an important role in the femtosecond pulsed laser ablation. The results of this paper are helpful in choosing the best technical parameters in femtosecond pulsed laser ablation. [ABSTRACT FROM AUTHOR]

Abstract: Titanium nitride or dioxide coatings have been reactively sputter-deposited under unstable sputtering conditions using a cold or hot target. We have shown that increasing the sputtered titanium flux in cold target sputtering (CTS), by increasing either the discharge current or the discharge voltage, increases the metalloid content in the coating deposited when the target operates at the higher reactive gas flow rate of the elemental sputtering mode. Using a hot target allows a perfect stabilisation of the process in the presence of an argon–nitrogen discharge, whereas only a slight stabilisation occurs when the sputtering stage takes place in argon–oxygen mixtures. It is shown that the stabilisation effect of hot target sputtering (HTS) is due to the strong increase of reactive species diffusion into the bulk target, which is more pronounced with nitrogen than with oxygen, as soon as the target heats up to the α-Ti→β-Ti transformation temperature. [Copyright &y& Elsevier]

Abstract: In this work, the formulas for the absorption coefficient and the absorptivity depending on target temperature are derived from Maxwell Equations and the Lambert–Beer''s law. A new theoretical model of laser ablation considering the temperature dependence of the absorption coefficient and the absorptivity has been developed. Then, as an example of Copper target, a finite difference method is employed to simulate the space-dependent and time-dependent absorption coefficient, absorptivity and temperature, as well as the time-dependent melt depth. The temperature evolution is compared with the result obtained from the heat conduction model taking the absorption coefficient and the absorptivity as constants. It is shown that the time-dependent absorption coefficient and absorptivity play an important role during the radiation of laser. Our calculated melt depth evolution is in better agreement with the experimental data than the result of the heat conduction model that regards the absorption coefficient and absorptivity as constants. Meanwhile, the corresponding physical mechanism is analyzed theoretically in detail. [Copyright &y& Elsevier]

The processes of ion back-scattering from the surfaces of various targets have been studied by means of the computer simulation (different modifications of the Monte-Carlo method). The analysis of the experimental and calculated data allows proposing the mechanism explaining the target temperature dependence of the shapes of the back-scattered ion spectra. The formula satisfactorily describing the dependence under study has been developed. [Copyright &y& Elsevier]

In this study, the influence of distance from focusing-lens to target-surface (DFTT) on the spectral characteristics of femtosecond and nanosecond laser-ablated Cu plasmas for different target temperatures was compared in air. The results showed that the spectral intensities were dependent on the DFTT and the target temperature. The spectral intensities increased with an up-regulation in the target temperature. In addition, as the target temperature increased, the maximum spectral emission and electron temperature moved away from the focusing-lens in the case of the femtosecond laser, while the maximum spectral emission and electron temperature moved closer to the focusing-lens in the case of the nanosecond laser. These phenomena were mainly based on the different pulse widths between femtosecond and nanosecond laser-ablated mechanisms. [Display omitted] • Increasing the target temperature can enhance the spectral intensity of the Cu plasmas. • Spectral intensities firstly increased, and then dropped with an increase in the DFTT. • Spectral maximum in fs moved away from focusing-lens as the target temperature increased. • Spectral maximum in ns moved close to focusing-lens as the target temperature increased. [ABSTRACT FROM AUTHOR]

Clinical questionIn unconscious patients of out-of-hospital cardiac arrest, does targeted temperature management to 36°C (96.8°F) improve outcomes compared to the standard target of 32°C–34°C (89.6°F–93.2°F)?Article chosenNielson N, Wetterslev J, Cronberg T, et al. Targeted temperature management at 33°C versus 36°C after cardiac arrest. N Engl J Med 2013;369:2197-2206.ObjectiveTo determine which temperature, 33°C (91.4°F) or 36°C (96.8°F), is associated with lower mortality and better neurologic function after cardiac arrest. [ABSTRACT FROM AUTHOR]

Thermal properties of the magnetron discharge with uncooled copper and chromium targets were studied experimentally and theoretically for DC and long HiPIMS (L-HiPIMS) operation modes. A set of thermal fluxes was considered to build a numerical model of the hot target exposed to DC and high-power pulsed plasma. The modeling results were tested in the experiments. The temperature of targets was measured directly in course of magnetron discharge operation with an elaborated contact thermocouple method. The measurements were made in two modes. At first the temporal evolution of temperature was recorded for a fixed applied discharge power. The results were found to well agree with temperature values expected from calculations. At 2 kW power, it takes ~50 s to reach the melting point of copper. The steady-state temperature values were also measured for a number of discharge power levels. The obtained dependence clearly demonstrated that the main mechanisms of the target heat balance at high temperatures are surface radiation and heat transfer due to thermal conductivity of the heat insulation supports between the target and water-cooled cathode. The parameters of DC hot target magnetron were compared to the high-power pulsed regime with the pulse-on time 20 ms. A promising method of a hot target magnetron discharge operation was considered that involves applying long (>20 ms) high-power pulses to the target pre-heated in the DC mode during the pulse-off period. • Thermal processes in hot target DC and L-HiPIMS modes were considered. • Temperature of uncooled Cu and Cr targets was measured with a contact method directly during the DC magnetron operation. • The results of numerical modeling agree with the experimental temperature data. • Pre-heated hot target L-HiPIMS pulse was modeled. [ABSTRACT FROM AUTHOR]