Bias Region Research Articles

Current-voltage (I-V) characteristics of Au/n-Ge heterostructure based on cobalt phthalocyanine (CoPc) interlayer

The influence of cobalt phthalocyanine (CoPc) interlayer on the I-V measurements of Au/n-Ge (pristine) contacts is investigated. I-V characteristics reveals the decrease in the reverse leakage current of CoPc interlayer contacts than compared to contacts without interlayer. The Schottky barrier parameters were described using forward I-V measurements by assuming standard thermionic emission mechanism. The barrier height (BH) of the contact with CoPc interlayer is significantly improved than compared to pristine contact. The observed BHs of pristine and CoPc interlayer contacts are found to be 0.63 eV and 0.67 eV respectively. Reduced interface state density and altered space charges on the n-Ge surface reduces tunneling resistance, may account for the larger BH observed in contacts with CoPc interlayer than pristine contacts. The series resistance evaluated for the contacts using Cheung’s method shows its consistency with Norde method. The observed series resistance value of the Au/CoPc/n-Ge contacts found to be significantly smaller in magnitude than Au/n-Ge contacts. The current conduction mechanism of pristine contact and contact with interlayer was evaluated using double logarithmic I-V plot in the forward bias region. Three regions of conduction mechanisms are observed for Au/CoPc/n-Ge contacts. It is evident that the CoPc interfacial layer considerably changes the conduction mechanism from ohmic conduction to trap charge limited current (TCLC) mechanism at moderately high voltages. The associated transition in the conduction mechanism might be due to the presence of shallow traps (low energy traps) with exponential distribution at the CoPc/n-Ge interface.

Updating and Evaluating Anthropogenic Emissions for NOAA’s Global Ensemble Forecast Systems for Aerosols (GEFS-Aerosols): Application of an SO2 Bias-Scaling Method

We updated the anthropogenic emissions inventory in NOAA’s operational Global Ensemble Forecast for Aerosols (GEFS-Aerosols) to improve the model’s prediction of aerosol optical depth (AOD). We used a methodology to quickly update the pivotal global anthropogenic sulfur dioxide (SO2) emissions using a speciated AOD bias-scaling method. The AOD bias-scaling method is based on the latest model predictions compared to NASA’s Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA2). The model bias was subsequently applied to the CEDS 2019 SO2 emissions for adjustment. The monthly mean GEFS-Aerosols AOD predictions were evaluated against a suite of satellite observations (e.g., MISR, VIIRS, and MODIS), ground-based AERONET observations, and the International Cooperative for Aerosol Prediction (ICAP) ensemble results. The results show that transitioning from CEDS 2014 to CEDS 2019 emissions data led to a significant improvement in the operational GEFS-Aerosols model performance, and applying the bias-scaled SO2 emissions could further improve global AOD distributions. The biases of the simulated AODs against the observed AODs varied with observation type and seasons by a factor of 3~13 and 2~10, respectively. The global AOD distributions showed that the differences in the simulations against ICAP, MISR, VIIRS, and MODIS were the largest in March–May (MAM) and the smallest in December–February (DJF). When evaluating against the ground-truth AERONET data, the bias-scaling methods improved the global seasonal correlation (r), Index of Agreement (IOA), and mean biases, except for the MAM season, when the negative regional biases were exacerbated compared to the positive regional biases. The effect of bias-scaling had the most beneficial impact on model performance in the regions dominated by anthropogenic emissions, such as East Asia. However, it showed less improvement in other areas impacted by the greater relative transport of natural emissions sources, such as India. The accuracies of the reference observation or assimilation data for the adjusted inputs and the model physics for outputs, and the selection of regions with less seasonal emissions of natural aerosols determine the success of the bias-scaling methods. A companion study on emission scaling of anthropogenic absorbing aerosols needs further improved aerosol prediction.

Effective carrier doping and quantum capacitance manipulation of graphene through two-dimensional solid electrolytes of ScI3 and YBr3

Effective carrier doping would be expected to enhance the electrical conductivity and further improve the quantum capacitance (Cq) of graphene. In this work, two-dimensional solid electrolytes of ScI3 and YBr3 as buffer layers have been proposed to modulate the carrier density and improve the Cq. By using first-principles calculations, the effective carrier doping has been examined by building heterostructures of graphene/ScI3 and graphene/YBr3 combined with Li, Na, K, Ca, F dopants. The n-type doping with electron density and p-type doping with hole density of graphene reach up to 1.14 × 1014 cm−2 and 6.66 × 1013 cm−2, respectively. Remarkably, the linear band dispersions of graphene are maintained near the Dirac point. Moreover, the Cq is significantly increased around the zero bias due to the increased density of states near the Fermi level. For Li-, Na-, K-, and Ca-doped systems, the Cq in the negative bias region is effectively enhanced while the Cq is improved in the positive bias region for F-doped system. These results provide an ideal route to implement the effective carrier doping and the Cq manipulation of graphene, facilitating the applications of graphene as electrodes in high-performance optoelectronics and energy storage devices, such as light-emitting diodes, solar cells and supercapacitors.

High-Speed Photodetector With Simultaneous Electrical Power Generation

We demonstrate a novel 850 nm high-speed photodetector for simultaneous high-speed data acquisition and electrical power generation from the optical signal. The device is based on GaAs/AlGaAs modified uni-traveling carrier photodetector (MUTC-PD). Compared with the traditional p-i-n photodetector with the same absorber thickness, the MUTC device sustains a high 3 dB bandwidth of 11.9 GHz and a power conversion efficiency of 38.5% under a forward bias of +0.7 V. This outstanding performance is achieved by first adopting the MUTC structure on LPC devices. The device is expected to have applications for simultaneous lightwave information and power transfer. Our approach extends the high-speed detection to the forward bias region and may provide a potential solution for next-generation combined power and data transceiver modules.

County-level analysis on occupation and ecological determinants of child abuse and neglect rates employing elastic net regression

BackgroundOccupation is a known determinant of worker physical and behavioral health risk, yet most previous studies have focused on unemployment, underemployment, and job satisfaction to understand child maltreatment risk. ObjectiveThis county-level study (n = 278) investigated the association between occupation and child maltreatment rates and community well-being in California, Colorado, Minnesota, Oregon, and New Mexico. Participants and settingStates were selected due to having comparable, publicly available county-level data on substantiated child abuse and neglect rates within a five-year span between 2015 and 2020. MethodsUsing US Census Bureau American Community Survey data, we collected percentages of the employed population among 13 occupations. Five additional community health indicators came from the County Health Rankings and Roadmaps. Elastic net linear regression was used for variable selection and because of explanatory variables' interrelationships. Linear regression was used to model individual industries positively associated with child abuse rates. ResultsThe elastic net model selected ten important variables in explaining child maltreatment rates. Important occupational sectors were agriculture, forestry, fishing (AFF), manufacturing, wholesale, retail, finance, and education. Important community indicators included housing, injury deaths, and poor mental health days. Only AFF and retail showed greater child abuse rates with increasing percentages of the workforce in these occupations in unadjusted models (AFF: β = 0.03 SE = 0.01, p = 0.02; Retail: β = 0.09 SE = 0.04, p = 0.02). ConclusionsOur findings suggest group-level effects of counties with a larger AFF and retail presence experiencing higher child maltreatment rates. Given that numerous prior studies of county economies note the strong associations of certain employment types with cultural attitudes, educational opportunities, regional biases, and other unmeasured variables, future studies should incorporate individual level data in a multilevel framework.

Multi-amplicon microbiome data analysis pipelines for mixed orientation sequences using QIIME2: Assessing reference database, variable region and pre-processing bias in classification of mock bacterial community samples.

Microbiome research relies on next-generation sequencing and on downstream data analysis workflows. Several manufacturers have introduced multi-amplicon kits for microbiome characterization, improving speciation, but present unique challenges for analysis. The goal of this methodology study was to develop two analysis pipelines specific to mixed-orientation reads from multi-hypervariable (V) region amplicons. A secondary aim was to assess agreement with expected abundance, considering database and variable region. Mock community sequence data (n = 41) generated using the Ion16S™ Metagenomics Kit and Ion Torrent Sequencing Platform were analyzed using two workflows. Amplicons from V2, V3, V4, V6-7, V8 and V9 were deconvoluted using a specialized plugin based on CutPrimers. A separate workflow using Cutadapt is also presented. Three reference databases (Ribosomal Database Project, Greengenes and Silva) were used for taxonomic assignment. Bray-Curtis, Euclidean and Jensen-Shannon distance measures were used to evaluate overall annotation consistency, and specific taxon agreement was determined by calculating the ratio of observed to expected relative abundance. Reads that mapped to regions V2-V9 varied for both CutPrimers and Cutadapt-based methods. Within the CutPrimers-based pipeline, V3 amplicons had the best agreement with the expected distribution, tested using global distance measures, while V9 amplicons had the worst agreement. Accurate taxonomic annotation varied by genus-level taxon and V region analyzed. For the first time, we present a microbiome analysis pipeline that employs a specialized plugin to allow microbiome researchers to separate multi-amplicon data from the Ion16S Metagenomics Kit into V-specific reads. We also present an additional analysis workflow, modified for Ion Torrent mixed orientation reads. Overall, the global agreement of amplicons with the expected mock community abundances differed across V regions and reference databases. Benchmarking data should be referenced when planning a microbiome study to consider these biases related to sequencing and data analysis for multi-amplicon sequencing kits.

Non-accidental injury in children-a sub-Saharan perspective on a multidisciplinary, co-ordinated care approach.

Non-accidental injury (NAI) in children presents a challenging problem to the pediatric neurosurgeon. The complexity of this condition is underscored by the heterogeneity in its terminology, the medicolegal requirements, and the socioeconomic implications for the family and the child in particular. Regional, social, and cultural biases as well as peculiarities in the different legal systems around the globe appear to have quite profound implications on the identification and management of this devasting condition in children. This work provides a glimpse into the sub-Saharan experience and perspective.

Effects of fast and thermal neutron irradiation on Ga-polar and N-polar GaN diodes

Studies of the radiation tolerance and electrical behavior of gallium nitride (GaN) based devices are important for the next generation of high-power and high-voltage electronics that may be subjected to harsh environments such as nuclear reactor and fusion facilities, particle accelerators, and post-denotation environments. In this work, we study the behavior of Ga-polar and N-polar GaN Schottky diodes before and after exposure to fast and thermal + fast neutrons. Temperature-dependent current–voltage (I–V) and circular transmission line method (CTLM) measurements were used to study the electrical characteristics. A strong reduction in reverse leakage current and an increase in differential resistance in forward bias were observed after neutron irradiation. Thermionic emission (TE), Frenkel–Poole (FP) emission, and Fowler–Nordheim (FN) tunneling models were used to explain the forward and reverse I–V characteristics pre- and post-irradiation. The study confirms that Ga-polar and N-polar GaN Schottky diodes exhibit different electrical responses to fast and thermal neutron irradiations. The reverse bias characteristics of N-polar diodes are less affected after the fast neutron irradiation compared to Ga-polar diodes, while in the forward bias region, the electrical behavior after fast and thermal neutron irradiations is similar in Ga-polar and N-polar diodes. The results indicate that the role of orientation should be considered in the design of GaN-based radiation-tolerant electronics.

Mangrove use by sharks and rays: a review

A wide variety of species depend on mangroves, making them essential habitats in tropical and subtropical regions. While the function of mangrove habitat is well studied for taxa such as teleost fishes, limited attention has been directed towards their value for elasmobranchs. Here, we review the available literature on how and why elasmobranchs use mangrove habitats based on 65 papers identified through literature searches. The use of mangrove habitat as nursery areas in combination with other coastal habitats has been well examined, although we found taxonomic and regional biases in research. Additionally, mangrove habitats are considered to offer elasmobranchs feeding opportunities and refuge from predators, yet such functions have rarely been tested. In particular, the ecological role of elasmobranchs within mangrove habitats is poorly known; as it is difficult to study their behaviour in complex mangroves, their feeding ecology is understudied as are trophic linkages between mangrove and adjacent ecosystems. For a greater understanding of the association between mangroves and elasmobranchs, direct observations of elasmobranch behaviour in mangrove habitats are needed. Given global concern regarding mangrove loss, understanding how this affects elasmobranch populations will require long-term studies, particularly in those regions where losses are greatest. We identify 8 key research questions that will help improve this understanding.

ИМПОРТОЗАМЕЩЕНИЕ В САРАТОВСКОЙ ОБЛАСТИ: РЕЗУЛЬТАТЫ И ПЕРСПЕКТИВЫ РАЗВИТИЯ

The implementation of foreign economic activity at the current stage of human development is an integral factor of qualitative and effective economic growth of any country. Modern world realities with the constant growth of global tensions lead to the closure of some product supply channels, which forces us to look for alternative ways and ways to purchase the necessary products. In this regard, there are several possible options for obtaining such goods, some of which are the search for foreign contractors for the supply of sanctioned products through third countries, the search for new partners or the development of their own production within their own country. Each of them has its own positive and negative features, but with the combined use of all three, we can achieve maximum results. So, if at the moment the necessary products cannot be produced due to a lack of technological base, it is necessary to use foreign analogies. However, at the same time, we should strive to establish our own production of domestic products within the framework of the import substitution program, which will avoid dependence on foreign countries. The release of new products will not only replace foreign products, but also create new high-tech jobs, increase the inflow of investments through the opening of new production facilities, as well as bring the quality of domestic products to a radically new level through state support of key and most vulnerable industries. The conducted research was carried out in order to study the process of import substitution with a regional bias. In addition, the current situation, results and directions of import substitution development are analyzed on the example of the Saratov region. Statistical data confirming the importance of import substitution for the stable functioning of the state are presented and analyzed. It is concluded that the correct alignment of priorities for the development of the region will make the region one of the main centers for import substitution of certain types of products, where we are able to successfully compete with foreign products.

Association between high-sensitive cardiac troponin level and coronary artery disease: A systematic review and meta-analysis

Background and objectives Previous studies suggest a link between high-sensitive cardiac troponin (hs-cTn) levels and coronary artery disease (CAD). However, the nature of this relationship is disputed. To address this, we conducted a study to gather and assess evidence on the association between hs-cTn and CAD prediction. Data sources Studies were systematically searched and collected from four databases and different types of gray literature to cover all available evidence. After the screening, the selected articles’ quality and risk of bias assessment were evaluated. Synthesis method Meta-analysis calculated std. mean difference on the extracted data. Furthermore, heterogeneity, sensitivity, subgroups, and publication bias analyses were assessed. Results Twenty-two studies were included in this systematic review, with a total of 844 cases and 2101 control people. The results of the meta-analysis on nine studies showed a significant and positive association between hs-cTn levels and CAD (pooled std. mean difference = 0.44; 95% confidence interval = 0.14–0.73; p < 0.003), with no publication bias ( p = 0.9170). Among subgroups, std. mean differences were notably different only when the data were stratified by region or risk of bias; however, subgroup analysis could not determine the source of heterogeneity. Conclusions Available prospective studies indicate a strong association of hs-cTn with the risk of CAD and significant improvements in CAD prediction. Further investigations in both molecular and clinical fields with proper methodology and more detailed information are needed to discover more evidence and underlying mechanisms to clear the interactive aspects of hs-cTn level in CAD patients.

Regional traditional gender stereotypes predict the representation of women in the workforce in 35 countries across five continents

Intergroup biases have been studied on an individual level for decades, but recent research has examined intergroup bias as a regional phenomenon. Aggregated responses on bias tests from individuals in geographic proximity have shown to relate to important society-level discriminatory outcomes. In the present research, we examined the pressing issue of gender inequalities in employment using this regional perspective on intergroup bias. Using large scale open-access datasets, we investigated how psychological measures of regional gender stereotypes associating men with careers and women with families (traditional gender stereotypes) related to the representation of women in the workforce and parental leave policies in 35 member countries of the Organization for Economic Co-operation and Development (OECD) across 5 continents. In countries with stronger traditional gender stereotypes, we found that women were less represented in the workforce and, specifically, in manager positions. Regional traditional gender stereotypes were inconsistently related to parental leave policies. These findings suggest that the framework of regional intergroup bias may be fruitful to explain regional differences in gender disparities.

A Physics-Based Analytical Formulation for the Tunneling Current Through the Base of Bipolar Transistors Operating at Cryogenic Temperatures

A physics-based analytical solution for the direct tunneling current through the base region of bipolar transistors operating at cryogenic temperatures (CTs) is derived. The obtained formulation is continuously differentiable over the entire bias region and contains only few experimentally determinable model parameters, which makes it well-suited for compact circuit modeling. Very good agreement of the new formulation with both a numerical evaluation of the tunneling current integral and experimental data of two silicon–germanium (SiGe) heterojunction bipolar transistor (HBT) process generations is demonstrated.

Home Bias: How Has It Affected the Border Effects of China’s Trade?

ABSTRACT This study aimed to analyze the impact of home bias on China’s trade border effects by constructing a pure exchange computable general equilibrium model. The results indicate that the border effects of external import, export, and trade in China are 6.96 times, 4.62 times, and 5.60 times their respective counterparts in interregional trade. On elimination of national bias, the border effects of China’s external import, export, and trade fell by 96.37%, 93.71%, and 95.18%, respectively, while border effects of China’s interregional trade became 8.06%. By eliminating regional bias, the border effects of China’s external imports, exports, and trade decreased by 3.63%, 6.29%, and 4.82%, respectively.

Remarkable Reduction in IG with an Explicit Investigation of the Leakage Conduction Mechanisms in a Dual Surface-Modified Al2O3/SiO2 Stack Layer AlGaN/GaN MOS-HEMT.

We demonstrated the performance of an Al2O3/SiO2 stack layer AlGaN/GaN metal-oxide semiconductor (MOS) high-electron-mobility transistor (HEMT) combined with a dual surface treatment that used tetramethylammonium hydroxide (TMAH) and hydrochloric acid (HCl) with post-gate annealing (PGA) modulation at 400 °C for 10 min. A remarkable reduction in the reverse gate leakage current (IG) up to 1.5×10-12 A/mm (@ VG = -12 V) was observed in the stack layer MOS-HEMT due to the combined treatment. The performance of the dual surface-treated MOS-HEMT was significantly improved, particularly in terms of hysteresis, gate leakage, and subthreshold characteristics, with optimized gate annealing treatment. In addition, an organized gate leakage conduction mechanism in the AlGaN/GaN MOS-HEMT with the Al2O3/SiO2 stack gate dielectric layer was investigated before and after gate annealing treatment and compared with the conventional Schottky gate. The conduction mechanism in the reverse gate bias was Poole-Frankel emission for the Schottky-gate HEMT and the MOS-HEMT before annealing. The dominant conduction mechanism was ohmic/Poole-Frankel at low/medium forward bias. Meanwhile, gate leakage was governed by the hopping conduction mechanism in the MOS-HEMT without gate annealing modulation at a higher forward bias. After post-gate annealing (PGA) treatment, however, the leakage conduction mechanism was dominated by trap-assisted tunneling at the low to medium forward bias region and by Fowler-Nordheim tunneling at the higher forward bias region. Moreover, a decent product of maximum oscillation frequency and gate length (fmax × LG) was found to reach 27.16 GHz∙µm for the stack layer MOS-HEMT with PGA modulation. The dual surface-treated Al2O3/SiO2 stack layer MOS-HEMT with PGA modulation exhibited decent performance with an IDMAX of 720 mA/mm, a peak extrinsic transconductance (GMMAX) of 120 mS/mm, a threshold voltage (VTH) of -4.8 V, a higher ION/IOFF ratio of approximately 1.2×109, a subthreshold swing of 82 mV/dec, and a cutoff frequency(ft)/maximum frequency of (fmax) of 7.5/13.58 GHz.

A detector block-pairwise dead time correction method for improved quantitation with a dedicated BrainPET scanner

‘Objective. Dead time correction (DTC) is an important factor in ensuring accurate quantification in PET measurements. This is currently often achieved using a global DTC method, i.e., an average DTC factor is computed. For PET scanners designed to image dedicated organs, e.g., those used in brain imaging or positron emission mammography (PEM), a substantial amount of the administered radioactivity is located outside of the PET field-of-view (FOV). This activity contributes to the dead time (DT) of the scintillation detectors. Moreover, the count rates of the individual scintillation detectors are potentially very inhomogeneous due to the specific irradiation of each detector, especially for combined MR/PET systems, where radiation shields cannot be applied. Approach: We have developed a block-pairwise DTC method for our Siemens 3T MR BrainPET insert by extending a previously published method that uses the delayed random coincidence count rate to estimate the DT in the individual scans and planes (i.e., scintillation pixel rings). The method was validated in decay experiments using phantoms with a homogenous activity concentration and with and without out-of-FOV activity. Based on a three-compartment phantom, we compared the accuracy and noise properties of the block-pairwise DTC and the global DTC method. Main results. The currently used global DTC led to a substantial positive bias in regions with high activity; the block-pairwise DTC resulted in substantially less bias. The noise level for the block-pairwise DTC was comparable to the global DTC and image reconstructions without any DTC. Finally, we tested the block-pairwise DTC with a data set obtained from volunteer measurements using the mGluR5 (metabotropic glutamate receptor subtype 5) antagonist [11C]ABP688. When the relative differences in activity concentrations obtained with global DTC and block-pairwise DTC for the ACC and the cerebellum GM were compared, the ratios differed by a factor of up to 1.4 at the beginning—when the first injection is administered as a bolus with high radioactivity. Significance. In this work, global DTC was shown to have the potential to introduce quantification bias, while better quantitation accuracy was achieved with the presented block-pairwise DTC method. The method can be implemented in all systems that use the delayed window technique and is particulary expected to improve the quantiation accuracy of dedicated brain PET scanners due to their geometry.’

Defect-Based Empirical Model for On-State Degradation in Sub-20-nm DRAM Periphery pFETs Under Arbitrary Condition

This work investigates the ON-state degradation under arbitrary stress conditions for periphery pFETs fabricated in the sub-20-nm DRAM technology. Three types of traps are identified, including the interface states, the oxide hole traps, and the oxide electron traps. By analyzing the time dependence, stress dependence, and lateral position, the generation mechanism for each type of trap is revealed, based on which a defect-based model was established. We proposed an effective model parameter extraction strategy and, thus, avoided overfitting. The predictive capability of the proposed model is further verified across the full bias regions at lower voltage conditions, including operating conditions. Finally, based on the model, the contributions of different types of traps to the degradation can be derived throughout the device’s entire lifetime. The work paves ways to link the defects to the device’s long-term reliability, which can be helpful for future process optimization and device/circuit co-optimization in DRAM peripheral circuits.

Influence of Shading on Solar Cell Parameters and Modelling Accuracy Improvement of PV Modules with Reverse Biased Solar Cells

This paper presents an experimental investigation on the influence of shading on mono-crystalline (mono-Si) solar cell parameters. The variations of equivalent circuit parameters with shading were determined and then used in modelling a mono-Si solar cell and a mono-Si photovoltaic (PV) module under partial shading. It was found that the simulation by considering the parameter variations with shading in the single cell model did not lead to a noticeable improvement in modelling accuracy. However, for the PV module, a significant improvement in modelling accuracy in the reverse bias region was achieved when considering all parameter variations in the model. A further investigation was performed to identify the key parameters that are responsible for the improvement. The results revealed that in addition to the photo-generated current, the shunt resistance also has a significant effect on the model accuracy. A modelling approach was thus proposed, which includes the variation of the shunt resistance with shading, in addition to the variation of the photo-generated current. This approach was experimentally validated using a mono-Si PV module. The results show that the proposed approach is more accurate, compared to the approach that considers only the variation of the photo-generated current, without the need to include an avalanche breakdown term.

Factors influencing alopecia areata treatment decisions: A qualitative assessment

Alopecia areata (AA) is a disease of hair loss in which patients may benefit from comprehensive understanding of AA's disease process and therapeutic options during treatment decision-making. Determine factors influencing patients' AA treatment decision-making. Qualitative interviews were conducted using semi-structured interview guides. Interviews were coded using inductive thematic analysis. Twenty-one participants with AA were interviewed. Coding interrater reliability was κ=0.87-0.91, indicating strong-almost perfect agreement. Participants faced multiple barriers, including lack of access to health care (n=10, 47.6%) and lack of transparency about their condition and treatment options (n=9, 42.9%). Information about AA was sought from primarily the internet (n=15, 71.4%) and physician recommendation (n=15, 71.4%). When choosing AA treatments, patients often considered treatment efficacy (n=21, 100%), safety (n=21, 100%), and convenience of use (n=20, 95.2%). Referral and regional biases may be present and limit generalizability. Patients with AA face various challenges including medical uncertainty and lack of information. Patients need trustworthy and accessible sources of information regarding their treatment that also take into consideration their preferences and values.

Joint Optimization of k-t Sampling Pattern and Reconstruction of DCE MRI for Pharmacokinetic Parameter Estimation

This work proposes to develop and evaluate a deep learning framework that jointly optimizes k-t sampling patterns and reconstruction for head and neck dynamic contrast-enhanced (DCE) MRI aiming to reduce bias and uncertainty of pharmacokinetic (PK) parameter estimation. 2D Cartesian phase encoding k-space subsampling patterns for a 3D spoiled gradient recalled echo (SPGR) sequence along a time course of DCE MRI were jointly optimized in a deep learning-based dynamic MRI reconstruction network by a loss function concerning both reconstruction image quality and PK parameter estimation accuracy. During training, temporal k-space data sharing scheme was optimized as well. The proposed method was trained and tested by multi-coil complex digital reference objects of DCE images (mcDROs). The PK parameters estimated by the proposed method were compared with two published iterative DCE MRI reconstruction schemes using normalized root mean squared errors (NRMSEs) and Bland-Altman analysis at temporal resolutions of [Formula: see text] = 2s, 3s, 4s, and 5s, which correspond to undersampling rates of R = 50, 34, 25, and 20. The proposed method achieved low PK parameter NRMSEs at all four temporal resolutions compared with the benchmark methods on testing mcDROs. The Bland-Altman plots demonstrated that the proposed method reduced PK parameter estimation bias and uncertainty in tumor regions at temporal resolution of 2s. The proposed method also showed robustness to contrast arrival timing variations across patients. This work provides a potential way to increase PK parameter estimation accuracy and precision, and thus facilitate the clinical translation of DCE MRI.