Strong-Isospin-Breaking Correction to the Muon Anomalous Magnetic Moment from Lattice QCD at the Physical Point

All lattice-QCD calculations of the hadronic-vacuum-polarization contribution to the muon's anomalous magnetic moment to date have been performed with degenerate up- and down-quark masses. Here we calculate directly the strong-isospin-breaking correction to a_{μ}^{HVP} for the first time with physical values of m_{u} and m_{d} and dynamical u, d, s, and c quarks, thereby removing this important source of systematic uncertainty. We obtain a relative shift to be applied to lattice-QCD results obtained with degenerate light-quark masses of δa_{μ}^{HVP,m_{u}≠m_{d}}=+1.5(7)%, in agreement with estimates from phenomenology.

Bs → Kℓv form factors with 2+1 flavors

Using the MILC 2+1 flavor asqtad quark action ensembles, we are calculating the form factors f0 and f+ for the semileptonic Bs → Kℓv decay. A total of six ensembles with lattice spacing from ≈ 0.12 to 0.06 fm are being used. At the coarsest and finest lattice spacings, the light quark mass m’l is one-tenth the strange quark mass m’s. At the intermediate lattice spacing, the ratio m’l/m’s ranges from 0.05 to 0.2. The valence b quark is treated using the Sheikholeslami-Wohlert Wilson-clover action with the Fermilab interpretation. The other valence quarks use the asqtad action. When combined with (future) measurements from the LHCb and Belle II experiments, these calculations will provide an alternate determination of the CKM matrix element |Vub|.

Semileptonic B-meson decays to light pseudoscalar mesons on the HISQ ensembles

We report the status of an ongoing lattice-QCD calculation of form factors for exclusive semileptonic decays of B mesons with both charged currents (B → πlv, Bs → Klv) and neutral currents (B → πl+l-, B → Kl+l-). The results are important for constraining or revealing physics beyond the Standard Model. This work uses MILC’s (2+1 + 1)-flavor ensembles with the HISQ action for the sea and light valence quarks and the clover action in the Fermilab interpretation for the b quark. Simulations are carried out at three lattice spacings down to 0.088 fm, with both physical and unphysical sea-quark masses. We present preliminary results for correlation-function fits.

B→πll Form Factors for New Physics Searches from Lattice QCD

The rare decay B→πℓ^{+}ℓ^{-} arises from b→d flavor-changing neutral currents and could be sensitive to physics beyond the standard model. Here, we present the first ab initio QCD calculation of the B→π tensor form factor f_{T}. Together with the vector and scalar form factors f_{+} and f_{0} from our companion work [J. A. Bailey et al., Phys. Rev. D 92, 014024 (2015)], these parametrize the hadronic contribution to B→π semileptonic decays in any extension of the standard model. We obtain the total branching ratio BR(B^{+}→π^{+}μ^{+}μ^{-})=20.4(2.1)×10^{-9} in the standard model, which is the most precise theoretical determination to date, and agrees with the recent measurement from the LHCb experiment [R. Aaij et al., J. High Energy Phys. 12 (2012) 125].

Determination of |V(us)|| from a lattice QCD calculation of the K → πℓν semileptonic form factor with physical quark masses

We calculate the kaon semileptonic form factor f+(0) from lattice QCD, working, for the first time, at the physical light-quark masses. We use gauge configurations generated by the MILC Collaboration with Nf = 2 + 1 + 1 flavors of sea quarks, which incorporate the effects of dynamical charm quarks as well as those of up, down, and strange. We employ data at three lattice spacings to extrapolate to the continuum limit. Our result, f+(0) = 0.9704(32), where the error is the total statistical plus systematic uncertainty added in quadrature, is the most precise determination to date. Combining our result with the latest experimental measurements of K semileptonic decays, one obtains the Cabibbo-Kobayashi-Maskawa matrix element |V(us)| = 0.22290(74)(52), where the first error is from f+(0) and the second one is from experiment. In the first-row test of Cabibbo-Kobayashi-Maskawa unitarity, the error stemming from |V(us)| is now comparable to that from |V(ud)|.

Leptonic-decay-constant ratio f(K+)/f(π+) from lattice QCD with physical light quarks

A calculation of the ratio of leptonic decay constants f(K+)/f(π+) makes possible a precise determination of the ratio of Cabibbo-Kobayashi-Maskawa (CKM) matrix elements |V(us)|/|V(ud)| in the standard model, and places a stringent constraint on the scale of new physics that would lead to deviations from unitarity in the first row of the CKM matrix. We compute f(K+)/f(π+) numerically in unquenched lattice QCD using gauge-field ensembles recently generated that include four flavors of dynamical quarks: up, down, strange, and charm. We analyze data at four lattice spacings a ≈ 0.06, 0.09, 0.12, and 0.15 fm with simulated pion masses down to the physical value 135 MeV. We obtain f(K+)/f(π+) = 1.1947(26)(37), where the errors are statistical and total systematic, respectively. This is our first physics result from our N(f) = 2+1+1 ensembles, and the first calculation of f(K+)/f(π+) from lattice-QCD simulations at the physical point. Our result is the most precise lattice-QCD determination of f(K+)/f(π+), with an error comparable to the current world average. When combined with experimental measurements of the leptonic branching fractions, it leads to a precise determination of |V(us)|/|V(ud)| = 0.2309(9)(4) where the errors are theoretical and experimental, respectively.

Refining new-physics searches in B→Dτν with lattice QCD

The semileptonic decay channel B→Dτν is sensitive to the presence of a scalar current, such as that mediated by a charged-Higgs boson. Recently, the BABAR experiment reported the first observation of the exclusive semileptonic decay B→Dτ(-)ν, finding an approximately 2σ disagreement with the standard-model prediction for the ratio R(D)=BR(B→Dτν)/BR(B→Dℓν), where ℓ = e,μ. We compute this ratio of branching fractions using hadronic form factors computed in unquenched lattice QCD and obtain R(D)=0.316(12)(7), where the errors are statistical and total systematic, respectively. This result is the first standard-model calculation of R(D) from ab initio full QCD. Its error is smaller than that of previous estimates, primarily due to the reduced uncertainty in the scalar form factor f(0)(q(2)). Our determination of R(D) is approximately 1σ higher than previous estimates and, thus, reduces the tension with experiment. We also compute R(D) in models with electrically charged scalar exchange, such as the type-II two-Higgs-doublet model. Once again, our result is consistent with, but approximately 1σ higher than, previous estimates for phenomenologically relevant values of the scalar coupling in the type-II model. As a by-product of our calculation, we also present the standard-model prediction for the longitudinal-polarization ratio P(L)(D)=0.325(4)(3).

[Artists, their performances, their muscles and their fears]

A thorough physical examination of the artist is a prerequisite of good physiotherapy. A musician should bring his/her instrument(s) and should undress in order to be examined. Being able to examine a dancer at the exercise barre is a significant advantage. In addition, this examination should always include quality medical iconography. Physiotherapy is a genuine treatment. This, however, also means that it has its own restrictions and involves dangers and contraindications.

Strange quark condensate in the nucleon in 2 + 1 flavor QCD

We calculate the "strange quark content of the nucleon," <N|s[over]s|N>, which is important for interpreting the results of some dark matter detection experiments. The method is to evaluate quark-line disconnected correlations on the MILC lattice ensembles, which include the effects of dynamical light and strange quarks. After continuum and chiral extrapolations, the result is <N|s[over]s|N> = 0.69(7)_{stat}(9)_{syst}, in the modified minimal subtraction scheme (2 GeV) regularization, or for the renormalization scheme invariant form, m_{s} partial differentialM_{N}/ partial differentialm_{s} = 59(6)(8) MeV.

[From the analogic to the digital era: technical EEG progress for presurgical investigations of refractory partial epilepsies]

Over the past two decades, exploration of epileptic patients has benefited from technological advances in electroencephalography. Computerized equipment can simultaneously retrieve cerebral electric activity and signs of the patient's ictal activity. The computer era has improved reliability, storage and analysis of the recorded data and provides easier communication tools for multidisciplinary staff and patient case studies. Therefore, an increasing number of patients could benefit from presurgical investigations and surgical treatment.

Charmed-meson decay constants in three-flavor lattice QCD

We present the first lattice QCD calculation with realistic sea quark content of the D+-meson decay constant f(D+). We use the MILC Collaboration's publicly available ensembles of lattice gauge fields, which have a quark sea with two flavors (up and down) much lighter than a third (strange). We obtain f(D+)=201+/-3+/-17 MeV, where the errors are statistical and a combination of systematic errors. We also obtain f(Ds)=249+/-3+/-16 MeV for the Ds meson.

Semileptonic decays of d mesons in three-flavor lattice QCD

We present the first three-flavor lattice QCD calculations for D-->pilnu and D-->Klnu semileptonic decays. Simulations are carried out using ensembles of unquenched gauge fields generated by the MILC Collaboration. With an improved staggered action for light quarks, we are able to simulate at light quark masses down to 1/8 of the strange mass. Consequently, the systematic error from the chiral extrapolation is much smaller than in previous calculations with Wilson-type light quarks. Our results for the form factors at q(2)=0 are f(D-->pi)(+)(0)=0.64(3)(6) and f(D-->K)(+)(0)=0.73(3)(7), where the first error is statistical and the second is systematic, added in quadrature. Combining our results with experimental branching ratios, we obtain the Cabibbo-Kobayashi-Maskawa matrix elements |V(cd)|=0.239(10)(24)(20) and |V(cs)|=0.969(39)(94)(24), where the last errors are from experimental uncertainties.

[The sportive certificate and...the responsibility!]

If your patient is an benevolent friendly sportsman (woman), you are able to do the sportive certificate. But mind! The responsibility of the physician is engaged if he signs without physical examination. The sports with competition and sports with danger so as parachutism, dive, alpinism and so on are reserved to specialist physician in sports.

[Physical violence: what about the certificate?]

It is of paramount importance to be precise when drawing up a report, in a case of aggravated assault. Such precision will serve to give the Judge a better conception of the extent of the injuries, the severity of the aggression, and thus of the eventual sentence. The extent of the injury must be determined, and the exact part of the body clearly stipulated. The general practitioner will be able to note the rections of the child standing in front of her. Is he frightened? or again his mental attitude? Furthermore, should a boy arrive at his surgery, stating that another doctor had refused to receive his family, one should be careful. The doctor must consider all the particular aspects of the case, and observe the child, speak to him, and endeavour to become his confidant. This will be time well spent, and will prove advantageous to the victim.

High-precision lattice QCD confronts experiment

The recently developed Symanzik-improved staggered-quark discretization allows unquenched lattice-QCD simulations with much smaller (and more realistic) quark masses than previously possible. To test this formalism, we compare experiment with a variety of nonperturbative calculations in QCD drawn from a restricted set of "gold-plated" quantities. We find agreement to within statistical and systematic errors of 3% or less. We discuss the implications for phenomenology and, in particular, for heavy-quark physics.

[Surgical treatment of distal femoral fractures using extra-medullary osteosynthesis]

Forty seven fractures of the distal femur treated by internal fixation using a supracondylar compression screw or blade plate were retrospectively evaluated regarding their radiological and functional results. Blade plates were used for all types of distal femoral fractures until 1992; their indications were subsequently restricted to simple supracondylar fractures whereas a compression screw was preferred for other types of fractures. Taking into account the condition of the patients before fracture, 85% good and very good results were achieved with both techniques. Malunions resulted in poor functional outcomes (50% good and very good results). Malunions were mainly observed in patients with complex fractures (90% of cases with malunion), which confirms the poor prognosis of comminuted fractures. Nonunions (65%) and infection (3%) resulted in poor functional results. The presence of a bony defect in the medial femoral cortex increases the risk of nonunion; bone grafting should be used in such cases. The recent use of a long femoro-femoral external distractor in a few patients has proved of value as it allowed to achieve accurate reduction and considerably eased fracture reduction and fixation.

[Primary malignant lymphoma of the spine: clinical aspects and therapeutic advances]

Malignant lymphomas are occasionally encountered in the spine, where they are usually secondary deposits. The authors report the case of a primary non-Hodgkin lymphoma of the L1 vertebra in whom surgical treatment (two operations and double approach) was followed by radiotherapy and chemotherapy. The diagnosis is often made at a late stage, when neurological deficits produced by epidural compression become evident. The surgical treatment is only palliative but has several goals: obtaining a biopsy, improving the neurological symptoms through decompression, stabilizing and "rebuilding" the spinal column; it is performed using posterior, anterior or combined approaches which are discussed. The combined surgical, radiotherapeutic and polychemotherapeutic treatment is associated with a 5-year survival rate of 60-80%. Such a prognosis justifies the risk of surgery which will lead to a stable and lasting reconstruction.

One-stage reconstruction of an infected skin and Achilles tendon defect with a composite distally planned lateral arm flap

In this paper, the treatment of a complicated Achilles tendon defect with a composite lateral arm flap with distal design of the skin paddle has been presented. The extended portion of the flap was sufficient to restore adequate contour to the posterior aspect of the ankle, and reinervation showed good protective sensation at 1 year. In terms of resurfacing, the use of the reinervated lateral arm flap with a distal design of the skin paddle seems advantageous. The weakening of the reconstructed Achilles tendon, although without clinical incidence and impairment of elbow extensors at this stage, may indicate that a better substitute than the triceps tendon has to be found. Nevertheless, we would best reconstruct such an Achilles tendon defect by the same technique because of the well vascularized autologous tissue it provides, limiting the risk of infection.

[Different arts of healing from the point of view of the private general practitioner]

The term "alternative medicine" conjures up a two-fold image, composed of two non-quantifiable phenomena--placebo, and scientifically unproved acts. In view of the extensive practice of this alternative approach, as evidenced by the large proportion of patients who have recourse to same--on grounds of relief or even complete recovery obtained--results that can only testify to the professional comptency of the practiotioner. At present, strict regulations are being liad down, limiting these alternative practices by nealer practitioners and kinesitherapists. Exposition of a subject does not necessarily imply acceptance of same.

[Surgical treatment of fractures of the radius neck in children using the Métaizeau technic]

Fractures of the radial neck in children must be reduced when the angular displacement is superior to 30 degrees. Given that orthopaedic reduction is difficult, internal fixation using closed intramedullary pinning, as described by Métaizeau in 1980, seems to be an elegant solution which preserves the vascularisation of the physis. The authors report their experience with this technique, which has been used to treat fifteen patients, with a mean age of nine years, between 1983 and 1996. A plaster cast was worn for three weeks after operation and sound union was observed at six weeks. Full functional recovery was observed in all patients at six weeks. No complication was encountered and the pins were removed at three months.

Expression of nitric oxide synthase isoforms in the thyroid gland: evidence for a role of nitric oxide in vascular control during goiter formation

The thyroid gland is a highly vascular tissue, and its blood flow changes dramatically in various pathological conditions. Although the mechanisms regulating these changes in vascularity and blood flow are not well understood, candidate mediators include endothelin-1 (ET-1) and nitric oxide (NO). In the present study, we used a reverse transcriptase-polymerase chain reaction assay to determine which components of these vasoregulatory pathways are present in the thyroid and to analyze changes in gene expression in an experimental model of goiter formation and involution. Expression of messenger RNAs (mRNAs) encoding ET-1, ET receptors (ETA and ETB), ET-converting enzyme, and the three nitric oxide synthase (NOS) isoforms (NOS I, NOS II, and NOS III) was readily detected in the rat thyroid. After goiter formation was induced by thiouracil and a low iodine diet, there was increased expression of the genes encoding ET-related proteins (ET-1, 3.2-fold; ETA, 2.9-fold; ETB, 3.5-fold) as well as two of the three NOS isoforms (NOS I, 2.7-fold; NOS III, 4.9-fold). During iodide-induced involution, the ET-related mRNA levels remained elevated, whereas those of the two NOS isoforms returned to basal values. ET-converting enzyme, NOS II, and thyroglobulin mRNAs were minimally affected in this model, providing evidence for selective regulation of these genes. To assess whether NO plays a role in vascular changes during goiter formation, animals were treated with a NOS inhibitor, N-nitro-L-arginine methyl ester (NAME). NOS activity in the thyroid was inhibited by more than 75% after treatment with NAME. Thyroid hormone and TSH levels were unchanged. Although NAME had little effect on overall thyroid size, vascular expansion during goiter formation was decreased by 36%. We conclude that the thyroid gland expresses a complex network of vasoactive genes whose expression is regulated dynamically during thyroid goiter formation and involution. NO production and probably other locally produced vasoactive substances are involved in changes in thyroid vascularization.

[Breast cancer from the general practitioner's viewpoint]

The problem of breast cancer remains a major preoccupation and a challenge for the general practitioner in his daily practice. In a telephonic consultation with several female colleagues, the latter were of the opinion that the master-plan still remains a rapid operation and psychological support after diagnosis. Specialized hospitals are sometimes feared; modern surgery is unappreciated.

[What if an artist calls at your office?]

This paper deals with various complaints of performing artists. Gone are the days when such matters were brushed aside with the comment: "If it hurts, give it up!" To-day, osteoarthropathy among patients, Satchmo's syndrome, fiddler's neck and so on are treated scientifically in specific medical textbooks. Whilst the performing artist's activities have their aesthetic or even poetic aspects, the physical element of risk is nevertheless ever present. All this, only for your entertainment. Who has ever met a dancer who has never complained of tiredness? Even after a long professional training, before he has reached thirty years of age he will often have suffered from such ailments as inflammation of the big toe, fracture of the fifth metatarsal bone, dislocation of the trigone bone, etc. Following brief general remarks, the reader will find four specific sections devoted to the most common pathologies among performing artists, classified by profession.