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Background To report the incidence and risk factors of suction loss during small incision lenticule extraction (SMILE). Methods This retrospective comparative case control study included 8493 eyes of 4261 patients. Patients underwent SMILE surgery between January 2014 and September 2019 were included. Videos of suction loss were reviewed, and the direct causes of suction loss were noted. An independent samples t-test was used for comparisons between the suction loss group and the control group. A binary logistic regression model was used to determine the possible significant risk factors that might increase the likelihood of suction loss during SMILE surgery. Results Suction loss occurred in 31 (0.37%) eyes of 30 patients; 23 (74.2%) cases occurred in the right eye (the first operative eye) and 8 (25.8%) cases occurred in the left eye. Among the 30 patients, 23 (76.7%) were male and 7 (23.3%) were female. The incidence in the six consecutive years were 0, 2.13, 0.34, 0.24, 0.22, and 0.25%. Head and eye movements during surgery caused suction loss in 16 (51.6%) and 15 (48.4%) eyes, respectively. Comparison between the suction loss group and the control group showed that the first operative eye and male sex are at a significantly high risk for suction loss (p Conclusions The risk factors of suction loss were first operative eye and male sex. Head and eye movements due to patient anxiety are the most common direct causes of suction loss. Surgeon’s experience may help to reduce the incidence of suction loss. Preoperative education and better communication during surgery needs to be emphasized. Trial registration Retrospectively registered. ChiCTR-ORC-17011040. Registered 1 April 2017. Name of registry: The observation of clinical results after corneal refractive surgery. Data of enrolment of the first participant to the trial: 1 January 2014.

This case highlights that hormonal changes during pregnancy could affect the biomechanical stability of the cornea and lead to corneal ectasia during pregnancy after corneal refractive surgery.We report an unusual case of bilateral corneal ectasia after small-incision lenticule extraction that developed during pregnancy.A 27-year-old woman experienced post-small-incision lenticule extraction corneal ectasia. Her pre-operative corneal topography was normal, with a minimum central corneal thickness of 538 μm in the right eye and 530 μm in the left eye. The manifest refraction was -7.75 -0.25 × 180 and -7.50 -0.75 × 10, and the lenticule thickness was 140 and 139 μm in the right and left eyes, respectively. After 11 months, in her first trimester, the patient began to experience gradually deteriorating blurred vision. Two years post-operatively, corneal ectasia was diagnosed based on topographic data. The automatic optometer examination was -7.25 -2.50 × 42 in the right eye and -11.00 -5.00 × 140 in the left eye. Later, the patient underwent corneal collagen cross-linking to control further progression and was recommended to wear rigid gas-permeable contact lenses.Surgeons should be alert for cornea ectasia after refractive surgery in pregnant patients, as hormonal changes during pregnancy may affect corneal biomechanical stability.

Background To investigate corneal higher-order aberrations (HOAs) of the anterior surface, posterior surface, and total cornea after small incision lenticule extraction (SMILE) in high myopic and mild to moderate myopic patients. Methods This retrospective study included 197 eyes (101 patients) undergoing SMILE surgery. According to the preoperative spherical equivalent (SE), treated eyes were divided into two groups: a high myopic group (more than − 6.0 D, Group H) and a mild to moderate myopic group (less than − 6.0 D, Group M). Corneal HOAs of the anterior surface, posterior surface, and total cornea were measured using a Scheimpflug camera preoperatively and 3 months postoperatively. Pearson’s correlation analysis was conducted to determine relationships between corneal aberrations and the SE. Results There were no significant differences in third-order to eight-order aberrations (RMS HOAs) of the anterior surface, posterior surface, and total corneal between the two groups before SMILE surgery. However, after SMILE, anterior and total corneal HOAs, especially vertical coma and spherical aberrations, significantly increased in both groups (p 0.0167). The induction of HOAs was significantly greater in Group H than Group M postoperatively (p

We calculate the complete form of the dimension-8 condensate contributions in the two-point correlator of the ( 1 − + , 0 + + ) light hybrid current considering the operator mixing under renormalization. We find the inclusion these higher power corrections as well as the update of 〈 g 3 G 3 〉 increase the QCD sum rule mass prediction for the 1 − + light hybrid. The obtained conservative mass range 1.72–2.60 GeV does not favor the π 1 ( 1400 ) and the π 1 ( 1600 ) to be pure hybrid states and suggests the π 1 ( 2015 ) observed by E852 is more likely to have much of a hybrid constituent. We also study the b 1 π and ρπ decay patterns of the 1 − + light hybrid with light-cone QCD sum rules. We obtain a relatively large partial decay width of the b 1 π mode, which is consistent with the predictions from the flux tube models and lattice QCD. More interestingly, using the tensor interpolating current we find the partial decay width of the ρπ mode is very small due to the lack of the leading twist contribution in the light-cone expansion of the correlation function.

Background To compare the refractive results and higher-order aberrations (HOAs) after small incision lenticule extraction (SMILE) in high myopia and mild to moderate myopia patients. Methods This prospective study included 165 eyes (86 patients) undergoing SMILE. According to the preoperative spherical equivalent (SE), treated eyes were divided into two groups: the high myopia group (more than -6.0 D, group-H) and the mild to moderate group (less than -6.0 D, group-M). Follow-up intervals were at 1 day, 10 days, 1 month and 3 months postoperatively. We obtained the following parameters: uncorrected (UDVA) and corrected distance visual acuity (CDVA), SE, efficacy and safety index, and HOAs. Results Preoperative SE was -7.16 ± 0.93 D in group-H and -4.34 ± 0.97 D in group-M. At 3 months postoperatively, the SE in group-H and group-M was -0.20 ± 0.37 D and 0.01 ± 0.19 D (t = - 4.11, P 0.05), respectively. There were significant increases in total HOAs, 3rd-order coma, and 4th-order spherical aberrations. Conclusions SMILE is an effective and safe surgery for correcting myopia. But the target correction amount in high myopia patients should be adjusted to avoid undercorrection and acquired more satisfaction. SMILE induced increases of HOAs. Trial registration ChiTrial registration number: ChiCTR-OON-16009164 . Retrospectively registered: 06.September.2016

Determination of disease biomarkers in clinical samples is of crucial significance for disease monitoring and public health. The dominating format is enzyme-linked immunosorbent assay (ELISA), which subtly exploits both the antigen-antibody reaction and biocatalytic property of enzymes. Although enzymes play an important role in this platform, they generally suffer from inferior stability and less tolerant of temperature, pH condition compared with general chemical product. Here, we demonstrate a metal-linked immunosorbent assay (MeLISA) based on a robust signal amplification mechanism that faithfully replaces the essential element of the enzyme. As an enzyme-free alternative to ELISA, this methodology works by the detection of α-fetoprotein (AFP), prostatic specific antigen (PSA) and C-reactive protein (CRP) at concentrations of 0.1 ng mL(-1), 0.1 ng mL(-1) and 1 ng mL(-1) respectively. It exhibits approximately two magnitudes higher sensitivity and is 4 times faster for chromogenic reaction than ELISA. The detection of AFP and PSA was further confirmed by over a hundred serum samples from hepatocellular carcinoma (HCC) and prostate cancer patients respectively.

In this paper, we reanalyze the $I=0$ scalar channel with the improved Monte-Carlo-based QCD sum rules, which combines the rigorous H\"older-inequality-determined sum rule window and a parametrization with two-Breit-Wigner-type resonances for the phenomenological spectral density that satisfies the low-energy theorem for the scalar form factor. Considering the uncertainties of the QCD parameters and the experimental masses and widths of the scalar resonances $\ensuremath{\sigma}$ and ${f}_{0}(980)$, we obtain a prediction for light quark mass ${m}_{q}(2\text{ }\text{ }\mathrm{GeV})=\frac{1}{2}({m}_{u}(2\text{ }\text{ }\mathrm{GeV})+{m}_{d}(2\text{ }\text{ }\mathrm{GeV}))={4.7}_{\ensuremath{-}0.7}^{+0.8}\text{ }\text{ }\mathrm{MeV}$, which is consistent with the Particle Data Group value and QCD sum rule determinations in the pseudoscalar channel. This agreement provides a consistent framework connecting QCD sum rules and low-energy hadronic physics. We also obtain the decay constants of $\ensuremath{\sigma}$ and ${f}_{0}(980)$ at 2 GeV, which are approximately 0.64--0.83 and 0.40--0.48 GeV, respectively.

We study the exotic ${J}^{PC}={0}^{\ensuremath{-}\ensuremath{-}}$ four-quark states in Laplace sum rules and finite energy sum rules. We use the vector tetraquarklike currents as interpolating currents in the correlator, from which the ${1}^{+\ensuremath{-}}$ states are also studied. In the mass extraction, we use the standard stability criterion with respect to the Borel parameters and the QCD continuum thresholds and consider the effect of the violation of factorization in estimating the high dimensional condensates as a source of uncertainties. The obtained mass prediction $1.76\ifmmode\pm\else\textpm\fi{}0.15\text{ }\text{ }\mathrm{GeV}$ is much lower than the previous sum rule predictions obtained using the pseudoscalar currents. Our result favors the four-quark interpretation of the possible $\ensuremath{\rho}\ensuremath{\pi}$ dominance in the ${D}^{0}$ decay. We also discuss the possible decay patterns of these exotic four-quark states.

Because traditional search engine has lots of defect such as return too much information or search result has little use, it is necessary to study on intelligent search engine. Base on the analysis of general search engine defects, this paper presents an intelligent search engine with multiple agent. Then, the structure and search process was discussed in detail. At last, the superiority of the new scheme was analyzed compared with the general search engine.

We improve the Monte-Carlo based QCD sum rules by introducing the rigorous H\"older-inequality-determined sum rule window and a Breit-Wigner type parametrization for the phenomenological spectral function. In this improved sum rule analysis methodology, the sum rule analysis window can be determined without any assumptions on OPE convergence or the QCD continuum.Therefore an unbiased prediction can be obtained for the phenomenological parameters (the hadronic mass and width etc.). We test the new approach in the $\rho$ meson channel with re-examination and inclusion of $\alpha_s$ corrections to dimension-4 condensates in the OPE. We obtain results highly consistent with experimental values. We also discuss the possible extension of this method to some other channels., Comment: 12 pages, 8 figures, accepted for publication in Chinese Physics C

QCD Laplace sum-rules are used to calculate axial vector $(J^{PC}=1^{++})$ charmonium and bottomonium hybrid masses. Previous sum-rule studies of axial vector heavy quark hybrids did not include the dimension-six gluon condensate, which has been shown to be important in the $1^{--}$ and $0^{-+}$ channels. An updated analysis of axial vector heavy quark hybrids is performed, including the effects of the dimension-six gluon condensate, yielding mass predictions of 5.13 GeV for hybrid charmonium and 11.32 GeV for hybrid bottomonium. The charmonium hybrid mass prediction disfavours a hybrid interpretation of the X(3872), if it has $J^{PC}=1^{++}$, in agreement with the findings of other theoretical approaches. It is noted that QCD sum-rule results for the $1^{--}$, $0^{-+}$ and $1^{++}$ channels are in qualitative agreement with the charmonium hybrid multiplet structure observed in recent lattice calculations.

We study the $\ensuremath{\rho}\ensuremath{\pi}$ and ${b}_{1}\ensuremath{\pi}$ decay modes of the ${1}^{\ensuremath{-}+}$ light hybrid state within the framework of light-cone QCD sum rules. We use both the tensor current $\overline{\ensuremath{\psi}}{\ensuremath{\sigma}}_{\ensuremath{\mu}\ensuremath{\nu}}\ensuremath{\psi}$ and the derivative current $\overline{\ensuremath{\psi}}{\stackrel{\ensuremath{\leftrightarrow}}{D}}_{\ensuremath{\mu}}{\ensuremath{\gamma}}_{5}\ensuremath{\psi}$ as interpolating currents to calculate the partial decay width of the ${b}_{1}\ensuremath{\pi}$ decay mode. Comparing the sum rules obtained by using different currents, we obtain $\mathrm{\ensuremath{\Gamma}}({\ensuremath{\pi}}_{1}\ensuremath{\rightarrow}{b}_{1}\ensuremath{\pi})=8--23$, 32--86 and 52--151 MeV for ${m}_{{1}^{\ensuremath{-}+}}=1.6$, 1.8 and 2.0 GeV respectively, which favor the results from the flux tube models and lattice simulations. We also use the tensor current to study the $\ensuremath{\rho}\ensuremath{\pi}$ decay mode, and although an extended stability criterion is needed, our results suggest a small partial decay width.

The following sections are included: Introduction Conventional Meson Spectrum Glueball Spectrum Hybrid Mesons Multiquarks Molecular States

The following sections are included: Baryons as qqq States Outstanding Problems in Baryon Spectroscopy Baryon Spectroscopy at BESI and BESII Prospects for Baryon Spectroscopy at BESIII

The following sections are included: Introduction Experimental Status of Two-Photon Processes Measurement of Two-Photon Processes at BES-III Summary

The following sections are included: Partially Conserved Vector Current (PCAC) and Soft Pions Beyond the Breit–Wigner Description of a Broad Resonance Final State Interaction Theorem and Omnés Solution On the Nature of the Lightest Scalar Resonances

Our knowledge about the structure of matter and the nature of the interactions between its constituent components follows a hierarchy that closely tracks the evolution of experimental measurements from low to higher and higher energies. For example, with an electron beam of a given energy, one can access the microscopic structure of matter at length scales corresponding to the de-Brogie wave length of the electrons that are being used: λ = 2π × 197.3 Mev · fm /Eγ, were Eγ is the energy of the photon that is exchanged in the experimentally observed process. As the energy of the beams that are available get higher and higher, the sizes of objects that can be probed get smaller and smaller…

To study proteomic changes in human lens epithelial cells (HLECs) exposed to 1800-MHz Global System for Mobile Communication (GSM)-like microwaves. In three separate experiments, HLECs were exposed and sham-exposed (six dishes each) to 1800-MHz GSM-like radiation for 2 h. The specific absorption rates were 1.0, 2.0, or 3.5 W/kg. Immediately after radiation, the proteome was extracted from the HLECs. Immobilized pH gradient two-dimensional polyacrylamide gel electrophoresis(2-DE; silver staining) and PDQuest 2-DE analysis software were used to separate and analyze the proteome of exposed and sham-exposed HLECs. Four differentially expressed protein spots were selected and identified by using electrospray ionization tandem mass spectrometry (ESI-MS-MS). When the protein profiles of exposed cells were compared with those of sham-exposed cells, four proteins were detected as upregulated. After analysis by ESI-MS-MS and through a database search, heat-shock protein (HSP) 70 and heterogeneous nuclear ribonucleoprotein K (hnRNP K) were determined to be upregulated in the exposed cells. Two-dimensional polyacrylamide gel electrophoresis combined with mass spectrometry may be a powerful tool for screening potential electromagnetic-reaction protein markers. HSP70 and hnRNP K are involved in the stress reaction of HLECs exposed to microwaves. These cell responses are nonthermal effects of the electromagnetic field. Jpn J Ophthalmol 2007;51:412–416 © Japanese Ophthalmological Society 2007

While serology represents the forefront technique for cancer diagnosis, current clinical methods for the detection of serum biomarkers have flaws in terms of the need of complicated manipulations, long analytical time, and high cost. Here, we develop a supramolecular glycoprobe for the quick serological detection of a cancer biomarker. The probe formed by agglutination between self-assembled glyco-gold nanoparticles and a lectin shows subtle optical variations upon the competitive recognition of a glycoprotein biomarker secreted by cancer cells, tumor-bearing mice, as well as clinical cancer patients, with no response to a series of controls including the serum of hepatitis patients. This research provides an insight into the development of effective tools for serological diagnosis of cancer.

We demonstrated a practical method to analyze carbohydrate–protein interaction based on single plasmonic nanoparticles by conventional dark field microscopy (DFM). Protein concanavalin A (ConA) was modified on large sized gold nanoparticles (AuNPs), and dextran was conjugated on small sized AuNPs. As the interaction between ConA and dextran resulted in two kinds of gold nanoparticles coupled together, which caused coupling of plasmonic oscillations, apparent color changes (from green to yellow) of the single AuNPs were observed through DFM. Then, the color information was instantly transformed into a statistic peak wavelength distribution in less than 1 min by a self-developed statistical program (nanoparticleAnalysis). In addition, the interaction between ConA and dextran was proved with biospecific recognition. This approach is high-throughput and real-time, and is a convenient method to analyze carbohydrate–protein interaction at the single nanoparticle level efficiently.

This study describes the simple preparation of core–shell glycosyl gold nanoparticles (AuNPs) using stepwise, copper-free click chemistry-promoted self-assembly. The as-formed glyco-AuNPs can be used for the selective detection of sugar–lectin interactions, which are vital to many important physiological and pathological processes. The approach uses AuNPs as bioprobes since they produce, sensitively, changes in both color visible to the naked eye and surface plasmon resonance (SPR), on aggregation. Strain-promoted click reaction of an azido galactoside with a lipid cyclooctyne affords a galactolipid that can be embedded into polyethylene glycol (PEG)-coated AuNP via self-assembly. Subsequently, using naked-eye and plasmon resonance scattering spectroscopy, we were able to observe the colorimetric and plasmonic variations of the glyco-AuNPs, respectively, in the presence of a selective lectin over other proteins.

Using the framework of the Heavy Quark Effective Theory we have re-analyzed the Isgur–Wise function describing semileptonic Λ b → Λ c decays in the QCD sum rule approach. The slope parameter of the Isgur–Wise function is found to be ρ 2 = 1.35 ± 0.13 , which is consistent with an experimental measurement and a lattice calculation. To O ( 1 / m b , 1 / m c ) of the heavy quark expansion the integrated Λ b decay width is used to extract the CKM matrix element V c b for which we obtain a value of | V c b | = 0.041 ± 0.004 ± 0.001 in excellent agreement with the value of | V c b | determined from semileptonic B → D ∗ decays.

We calculate the coefficients of the dimension-8 quark and gluon condensates in the current-current correlator of $1^{-+}$ light hybrid current $g\bar{q}(x)\gamma_{\nu}iG_{\mu\nu}(x)q{(x)}$. With inclusion of these higher-power corrections and updating the input parameters, we re-analyze the mass of the $1^{-+}$ light hybrid meson from Monte-Carlo based QCD sum rules. Considering the possible violation of factorization of higher dimensional condensates and variation of $\langle g^3G^3\rangle$, we obtain a conservative mass range 1.72--2.60\,GeV, which favors $\pi_{1}(2015)$ as a better hybrid candidate compared with $\pi_{1}(1600)$ and $\pi_{1}(1400)$., Comment: 12pages, 2 figures, the version appearing in JHEP

We discuss the possible corrections of some recent calculations on the form factors which parametrize the matrix element of the decays {ital B}({ital D}){r_arrow}{pi}{ital l}{nu}. These calculations are based on the assumption that the {ital B}{sup {asterisk}}({ital D}{sup {asterisk}}) pole contribution is fully dominant near zero recoil. By using the Bethe-Salpeter approach, we calculate some low-lying state pole terms predicted by the quark model. The numerical results are obtained to the next-leading order of the 1/{ital M} expansion. {copyright} {ital 1996 The American Physical Society.}

We introduce the vector meson contributions in heavy-light chiral perturbation theory (HLCPT) and construct the Lagrangian and current to the order 1/mQ. With this, to the order (Λcsb is the chiral symmetry breaking scale) we calculate corrections to fD and fB arising from coupled-channel effects to the orders 1/mc, and 1/mb. At the tree level in HLCPT, using the relativistic Bethe–Salpeter (BS) equation with the kernel containing a confinement term and a gluon exchange term in a covariant generalization of the coulomb gauge we calculate and when mQ → ∞ as well as the 1/mQ corrections. HLCPT and the heavy quark effective theory (HQET) are matched at the scale Λcsb. Adding the perturbative and nonperturbative contributions we give the values for fD and fB, respectively. It is found that our result is in agreement with the relation fD = fB from lattice calculations.

General formulas for decay widths of heavy mesons with arbitrary spin and parity to the heavy meson ground state plus a {pi} or {ital K} are derived in the leading order of the 1/{ital M} expansion in the relativistic BS equation. Numerical results for various partial decay widths of 1{sup +}, 2{sup +} doublets in the {ital D}, {ital D}{sub {ital s}}, {ital B}, and {ital B}{sub {ital s}} series are obtained with a kernel used previously to obtain the spectra of low-lying states in these series, in good agreement with experiments. The results are in satisfactory agreement with the experimental data when they are available.

We present the 1/M relativistic B-S expansion formalism for heavy mesons, explain its relation to HQET and give further simplified formulas. The numerical results for the decay rates of 1− and 0+ heavy mesons including the effects of the order 1/M are obtained with a model which has been used successfully to the spectra of heavy mesons.

In order to solve the problem of ignoring the correlation between class labels, this paper describes a new method for multi-label classification based on the frequent item sets to classify an unseen instance on the basis of its k nearest neighbors ( MLFI-KNN). For each unseen instance, MLFI-KNN takes its k-nearest neighbors in the training set and counts the number of occurrences of each label in this neighborhood, and then utilizes the FP-growth algorithm to obtain the frequent item sets between the labels that these neighboring instances include, in order to determine the predicted label set. Experiments on benchmark dataset demonstrate the effectiveness of the proposed approach as compared to some existing well-known methods.

Axial vector $(J^{PC}=1^{++})$ charmonium and bottomonium hybrid masses are determined via QCD Laplace sum-rules. Previous sum-rule studies in this channel did not incorporate the dimension-six gluon condensate, which has been shown to be important for $1^{--}$ and $0^{-+}$ heavy quark hybrids. An updated analysis of axial vector charmonium and bottomonium hybrids is presented, including the effects of the dimension-six gluon condensate. The axial vector charmonium and bottomonium hybrid masses are predicted to be 5.13 GeV and 11.32 GeV, respectively. We discuss the implications of this result for the charmonium-like XYZ states and the charmonium hybrid multiplet structure observed in recent lattice calculations., Comment: 10 pages, 7 figures. Updated to match published version

In this paper, we study instanton contributions to the correlator of the hybrid current $g\bar q \sigma_{\mu\nu}G^a_{\nu\mu}T^a q$. These contributions are then included in a QCD sum-rule analysis of the isoscalar $0^{++}$ hybrid mass. We find a mass at 1.83 GeV for the $(\bar uug+\bar ddg)/\sqrt{2}$ hybrid. However, for the $\bar ssg$ hybrid, we find the sum rules are unstable. We also study non-zero width effects, which affect the mass prediction. The mixing effects between these two states are studied and we find QCD sum rules support the existence of a flavor singlet hybrid with mass at around 1.9 GeV. Finally, we study the mixing effects between hybrid and glueball currents. The mixing between the $(\bar uug+\bar ddg)/\sqrt{2}$($\bar ssg$) and the glueball causes two states, one in the region 1.4-1.8 GeV(1.4-2.2 GeV), and the other in the range 1.8-2.2 GeV(2.2-2.6 GeV)., Comment: 12 pages, revised version

By use of single instanton approximation the twist-3 light-cone distribution amplitudes of pion as well as the p-wave mesons, i.e., $f_{0}(1370)$, $K_{0}^{\ast}(1430)$ and $a_{0}(1450)$ are investigated within the framework of QCD moment sum rules with inclusion of instanton effects based on the valence quark model. Results show that there is much change on light-cone distribution amplitudes by the isospin- and chirality-dependent instanton contribution compared with the instanton-free ones. We find the intanton involved twist-3 LCDAs are non-positive-definite within some range of momentum fraction and there are rapid changes at two ends of momentum fraction. To guarantee the convergence of moments by the method in this work a low instanton density should be adopted, for instance $n_{c}=1/2\rm{fm^{-4}}$ is welcomed. Possible ingredients which might have impact on the results are briefly discussed. These light-cone distribution amplitudes may be helpful to analyze exclusive heavy flavored processes., 25 pages, 6 figures, the version appearing in PRD

The most general form of covariant B-S wave functions and the corresponding integral equations for heavy mesons with arbitrary spin and parity are obtained in the infinite mass limit. A general formula for the I-W functions for transitions between states with arbitrary spin-parity and the ground state is given in terms of these wave functions. Using the covariant instantaneous approximation we apply this formulism to calculate I-W functionsr1/2,r3/2 and rates of processes in which a π or γ is emitted in the transitions 1−→0−, 0+→0−, 1+→1−.

We adopted the form of v.e.v. of the bulk scalar field proposed by P.Zhang in this paper, and changed the dilaton background from $e^{-\kappa^2z^2}$ to $e^{-\kappa^2z^2+\alpha z}$ accordingly. The calculation shows that, as if we choose proper parameters, we can get a better result than both the present soft-wall models and the hard-wall model while keeping Regge behavior unchanged., Comment: 8 pages, 1 figure

We calculate the two-pion exchange potential between a heavy meson and a heavy baryon. We find this potential is as strong as the one-pion exchange potential between two heavy mesons and is enough to bind $\Lambda_b-\bar B$. Though our result is sensitive to the cut-off, the value of the cut-off is in the reasonable region., Comment: 11 pages, 3 figures, replace the old verson which does not correspond to the published version

We discuss the spin-flavor symmetry in the heavy quark limit from the view of theB-S approach and use the potential model to compute the slope of the Isgur-Wise function at zero recoil and predict masses of theB meson doublet withJp=1+, 2+ to order of 1/MQ.

Motivated by the similar mass splitting in light-light and heavy-light meson system in $J^{P}=0^{-}$ and $J^{P}=0^{+}$ channel, taking into account the operator mixing to obtain an infrared stable OPE as well as a complete both non-perturbative and perturbative $\mathcal {O}(m_{q})$ corrections to the correlation function, the SU(3)-symmetry breaking effects in mass splitting in $0^{-}$ and $0^{+}$ channel of $D$ meson are analyzed by QCD sum rule approach based on a $c\bar{q}$ underlying structure. Within the sum rule we get, taking same threshold and Borel window for same channel, we find a correct mass splitting tendency in both channel which agrees with observed spectrum. We find $m_{D_{s}}-m_{D_{d}}\sim35\rm{MeV}$ in $0^{-}$ channel and $m_{D_{d}}-m_{D_{s}}\sim12\rm{MeV}$ in $0^{+}$ channel at scale $\mu=1\rm{GeV}$. These splitting can be accommodated with the different role of combination of mass effects and the parity-dependent "force" induced from non-perturbative QCD vacuum. When we scale up to $\mu=1.3\rm{GeV}$, the splitting remains unchanged which demonstrates a correct scale invariance. Combined with HQET, generalization to other channel of charmed meson and $b$-system are discussed briefly also., Comment: 24pages, six figures and three tables, the version appears in PRD.

A crucial part in the gene structure prediction is to identify the accurate splice sites, not only constitutive but also alternative ones. Here, we use the maximum information principle (MIP) to analyze the conservative segments around splice sites. According to the MIP, a reaction free energy (RFE) expression is deduced, which can be employed to estimate the free energy change during splicing reaction involving a donor or acceptor site. The expression contains not only the background probability factors, but also all kinds of dependencies among both adjacent and non-adjacent bases. We apply the RFE expression to recognize splice sites and their flanking competitors in human genes, the results show high sensitivity and specificity, so the RFE expression accords well with the splicing reaction process. Moreover, the RFE expression is better than previous methods for predicting competitors of splice sites, and it outperforms the reaction free energy subtraction (RFES), that implies RFE competition between a given splice site and its flanking competitor may not be an only primary factor for alternative splice site selection. The work is helpful to not only the understanding of splicing reaction from its relation to MIP, but also the research on computational recognition of splicing sites and alternative splice events.