19 research outputs found
Constructions of Binary Optimal Locally Repairable Codes via Intersection Subspaces
Locally repairable codes (LRCs), which can recover any symbol of a codeword
by reading only a small number of other symbols, have been widely used in
real-world distributed storage systems, such as Microsoft Azure Storage and
Ceph Storage Cluster. Since binary linear LRCs can significantly reduce coding
and decoding complexity, constructions of binary LRCs are of particular
interest. The aim of this paper is to construct dimensional optimal binary
locally repairable codes with disjoint local repair groups. We introduce how to
connect intersection subspaces with binary locally repairable codes and
construct dimensional optimal binary linear LRCs with locality () and minimum distance by employing intersection subspaces deduced
from the direct sum. This method will sufficiently increase the number of
possible repair groups of dimensional optimal LRCs, and thus efficiently
expanding the range of the construction parameters while keeping the largest
code rates compared with all known binary linear LRCs with minimum distance
and locality ().Comment: Accepted for publication in the SCIENCE CHINA Information Science
Diverse Target and Contribution Scheduling for Domain Generalization
Generalization under the distribution shift has been a great challenge in
computer vision. The prevailing practice of directly employing the one-hot
labels as the training targets in domain generalization~(DG) can lead to
gradient conflicts, making it insufficient for capturing the intrinsic class
characteristics and hard to increase the intra-class variation. Besides,
existing methods in DG mostly overlook the distinct contributions of source
(seen) domains, resulting in uneven learning from these domains. To address
these issues, we firstly present a theoretical and empirical analysis of the
existence of gradient conflicts in DG, unveiling the previously unexplored
relationship between distribution shifts and gradient conflicts during the
optimization process. In this paper, we present a novel perspective of DG from
the empirical source domain's risk and propose a new paradigm for DG called
Diverse Target and Contribution Scheduling (DTCS). DTCS comprises two
innovative modules: Diverse Target Supervision (DTS) and Diverse Contribution
Balance (DCB), with the aim of addressing the limitations associated with the
common utilization of one-hot labels and equal contributions for source domains
in DG. In specific, DTS employs distinct soft labels as training targets to
account for various feature distributions across domains and thereby mitigates
the gradient conflicts, and DCB dynamically balances the contributions of
source domains by ensuring a fair decline in losses of different source
domains. Extensive experiments with analysis on four benchmark datasets show
that the proposed method achieves a competitive performance in comparison with
the state-of-the-art approaches, demonstrating the effectiveness and advantages
of the proposed DTCS
Resolving spin, valley, and moir\'e quasi-angular momentum of interlayer excitons in WSe2/WS2 heterostructures
Moir\'e superlattices provide a powerful way to engineer properties of
electrons and excitons in two-dimensional van der Waals heterostructures. The
moir\'e effect can be especially strong for interlayer excitons, where
electrons and holes reside in different layers and can be addressed separately.
In particular, it was recently proposed that the moir\'e superlattice potential
not only localizes interlayer exciton states at different superlattice
positions, but also hosts an emerging moir\'e quasi-angular momentum (QAM) that
periodically switches the optical selection rules for interlayer excitons at
different moir\'e sites. Here we report the observation of multiple interlayer
exciton states coexisting in a WSe2/WS2 moir\'e superlattice and unambiguously
determine their spin, valley, and moir\'e QAM through novel resonant optical
pump-probe spectroscopy and photoluminescence excitation spectroscopy. We
demonstrate that interlayer excitons localized at different moir\'e sites can
exhibit opposite optical selection rules due to the spatially-varying moir\'e
QAM. Our observation reveals new opportunities to engineer interlayer exciton
states and valley physics with moir\'e superlattices for optoelectronic and
valleytronic applications
Influence of Type 1 Diabetes Mellitus on the Ocular Biometry of Chinese Children
Purpose. To compare ocular biometry between children with type 1 diabetes mellitus (T1DM) and healthy children in China and to determine the correlation of ocular biometry with the glycosylated hemoglobin (HbA1c) level and diabetes duration. Methods. A case-control study was conducted at Children’s Hospital of Fudan University between T1DM children and healthy children. The participants were evaluated for central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), K1 and K2 keratometry, and axial length (AL); also cycloplegic refraction was performed, and spherical equivalent (SE) was acquired. HbA1c levels of the T1DM cases were obtained. Results. Fifty-four eyes of 54 children with T1DM and 53 eyes of 53 healthy children were included. The mean age of T1DM group and control group was 10.59 ± 3.40 years and 9.55 ± 1.89 years, respectively, and the differences between age and gender were not significant (p=0.052, p=0.700). The mean LT in T1DM group (3.49 ± 0.18 mm) was thicker than that in the control group (3.40 ± 0.16 mm) (p=0.018), the mean ACD in T1DM group (3.52 ± 0.26 mm) was shallower than that in the control group (3.72 ± 0.26 mm) (p<0.001), and there were no significant differences of CCT, K1, K2, AL, and SE (p=0.088, p=0.672, p=0.821, p=0.094, and p=0.306, respectively). There was no significant correlation between HbA1c or diabetes duration and ocular biometry. Conclusions. Thicker LT and shallower ACD occurred in T1DM children rather than age-matched and sex-matched healthy children, but the overall refraction was not affected. HbA1c or diabetes duration was not correlated with ocular biometry in T1DM children
Compression Garments Reduce Soft Tissue Vibrations and Muscle Activations during Drop Jumps: An Accelerometry Evaluation
Objectives: To explore the effects of wearing compression garments on joint mechanics, soft tissue vibration and muscle activities during drop jumps. Methods: Twelve healthy male athletes were recruited to execute drop jumps from heights of 30, 45 and 60 cm whilst wearing compression shorts (CS) and control shorts (CON). Sagittal plane kinematics, ground reaction forces, accelerations of the quadriceps femoris (QF), hamstrings (HM) and shoe heel-cup, and electromyography images of the rectus femoris (RF) and biceps femoris (BF) were collected. Results: Compared with wearing CON, wearing CS significantly reduced the QF peak acceleration at 45 and 60 cm and the HM peak acceleration at 30 cm. Wearing CS significantly increased the damping coefficient for QF and HM at 60 cm compared with wearing CON. Moreover, the peak transmissibility when wearing CS was significantly lower than that when wearing CON for all soft tissue compartments and heights, except for QF at 30 cm. Wearing CS reduced the RF activity during the pre-, post-, and eccentric activations for all heights and concentric activations at 45 cm; it also reduced the BF activity during post- and eccentric activations at 30 and 60 cm, respectively. The hip and knee joint moments and power or jump height were unaffected by the garment type. Conclusion: Applying external compression can reduce soft tissue vibrations without compromising neuromuscular performance during strenuous physical activities that involve exposure to impact-induced vibrations
Enantioselective synthesis of chiral quinohelicenes through sequential organocatalyzed Povarov reaction and oxidative aromatization
Abstract Heterohelicenes are of increasing importance in the fields of materials science, molecular recognition, and asymmetric catalysis. However, enantioselective construction of these molecules, especially by organocatalytic methods, is challenging, and few methods are available. In this study, we synthesize enantioenriched 1-(3-indol)-quino[n]helicenes through chiral phosphoric acid-catalyzed Povarov reaction followed by oxidative aromatization. The method has a broad substrate scope and offers rapid access to an array of chiral quinohelicenes with enantioselectivities up to 99%. Additionally, the photochemical and electrochemical properties of selected quinohelicenes are explored
Biocontrol: Endophytic bacteria could be crucial to fight soft rot disease in the rare medicinal herb, Anoectochilus roxburghii
Abstract Microbial destabilization induced by pathogen infection has severely affected plant quality and output, such as Anoectochilus roxburghii, an economically important herb. Soft rot is the main disease that occurs during A. roxburghii culturing. However, the key members of pathogens and their interplay with non‐detrimental microorganisms in diseased plants remain largely unsolved. Here, by utilizing a molecular ecological network approach, the interactions within bacterial communities in endophytic compartments and the surrounding soils during soft rot infection were investigated. Significant differences in bacterial diversity and community composition between healthy and diseased plants were observed, indicating that the endophytic communities were strongly influenced by pathogen invasion. Endophytic stem communities of the diseased plants were primarily derived from roots and the root endophytes were largely derived from rhizosphere soils, which depicts a possible pathogen migration image from soils to roots and finally the stems. Furthermore, interactions among microbial members indicated that pathogen invasion might be aided by positively correlated native microbial members, such as Enterobacter and Microbacterium, who may assist in colonization and multiplication through a mutualistic relationship in roots during the pathogen infection process. Our findings will help open new avenues for developing more accurate strategies for biological control of A. roxburghii bacterial soft rot disease
Estrogen Regulation of Proteinase Inhibitor 9 Gene Expression and Interleukin-1beta Production
148 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2001.The ability of several estrogens and antiestrogens to activate PI-9 gene expression was assessed by transient transfection. Of interest, the mixed agonist/antagonist tamoxifen (OHT) was an agonist on the transiently transfected reporter gene but behaved as an antagonist on the cellular gene. To begin to assess how OHT-ER interacts with the native PI-9 promoter we carded out chromatin immunoprecipitation (ChIP) assays. The ChIP assays demonstrated that moxestrol-ER complex bound to the PI-9 promoter, but that OHT-ER (and unliganded ER) did not bind. These data provide the first evidence that the agonist activity of OHT-ER stems from the inability of OHT to elicit conformational changes in chromatin which allow ER to bind to ERE's.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD
SNP typing using the HID-Ion AmpliSeq™ Identity Panel in a Southern Chinese population
In the present study, 90 autosomal single nucleotide polymorphisms (SNPs) and 34 Y chromosomal SNPs were sequenced simultaneously using HID-Ion AmpliSeq™ Identity Panel on the Ion PGM™ platform for 125 samples in a southern Chinese population. Raw data were analyzed and forensic parameters were calculated. Haplogrouping concordance was also assessed using alternative methods based on Y-SNP haplotypes and Y-STR haplotypes. The results showed that allelic imbalance occurred more frequently with low coverage while several SNPs with high coverage were also observed with poor allelic balance, including rs214955, rs430046, rs7520386, rs876724, rs9171188, rs16981290, and rs2032631. Totally, 21,261 miscalled reads (0.28%) were observed. The rate of allele-specific miscalled reads (ASMRs) was higher than that of allele nonspecific miscalled reads (ANMRs) and associated with genetic diversity of the SNP. The ASMRs of major allele were lower than that of minor allele while there was no difference for ANMRs. The combined discrimination power (CDP) was 1–4.81\ua0×\ua010 and the combined power of exclusion (CPE) was 0.99989 and 0.99999992 for duo and trio paternity testing, respectively. No significant genetic difference was detected between southern and northern Chinese populations. For haplogroup study, O2 was the predominant haplogroup and 97.01% of samples were assigned consistent haplogoups with Y-SNP and Y-STR haplotypes. In conclusion, the AmpliSeq™ Identity Panel was powerful for individual identification and trio paternity testing. ASMRs were associated with the genetic diversity and allele frequency while neither was related for ANMRs. High concordance of haplogrouping assignment can be obtained with Y-STR and Y-SNP haplotypes