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Context: Although anterior cruciate ligament (ACL) tears are relatively common in athletic populations, few studies have systematically reviewed graft choice in young women.Objective: To quantitatively and qualitatively examine reported outcomes for graft choice in women aged 25 years and younger undergoing primary ACL reconstruction.Data Source: A systematic review was performed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. An electronic search in the PubMed (includes MEDLINE) and EMBASE databases was completed using a combination of key terms.Study Selection: Studies were included if they reported graft choice outcomes in women aged 25 years and younger.Study Design: Systematic review.Level of Evidence: Level 4.Data Extraction: The following information was extracted: title, author, year of publication, number of female patients and age, graft type, follow-up, and patient-reported outcome measures. The following outcome scores were identified as being reported or not reported by each study: graft failure, contralateral ACL (CACL) rupture, IKDC (International Knee Documentation Committee), graft survival (Kaplan-Meier), Lysholm, Tegner, KT-1000, kneeling pain, return to sport, and Lachman.Results: Of 1170 identified articles, 16 met inclusion criteria, reporting on 1385 female patients aged 25 years and younger. Comparison of 655 bone–patellar tendon–bone (BPTB) versus 525 hamstring tendon (HT) autografts showed significant differences in mean failure rate between BPTB autografts (6.13% ± 2.58%) and HT autografts (17.35% ± 8.19%), P= 0.001. No statistically significant differences in CACL failure rates were found between BPTB autografts and HT autografts (P= 0.25). Pooled results for IKDC were possible in 3 of the HT autograft studies, showing a mean score of 88.31 (95% CI 83.53-93.08). Pooled Lysholm score results were possible in 2 of the HT autograft studies, showing a mean score of 93.46 (95% CI 91.90-95.01).Conclusion: In female patients aged 25 years and younger, BPTB autografts showed significantly less graft failure compared with HT autografts. However, BPTB autografts had comparable patient-reported outcomes compared with HT autografts with the available data. The overall state of evidence for graft choice in female patients aged 25 years and younger is low. Future studies should report statistics by age and sex to allow for further analysis of graft choice for this specific population that is known to be more vulnerable to ACL injury.

AbstractThis retrospective study examined clinical parameters associated with amantadine treatment of psychiatric symptoms in children. A total of 297 pediatric patients were prescribed amantadine and met study criteria to assess clinical responses and medication outcomes. More than 62% of patients experienced clinically significant symptom control and 83% achieved at least maintenance symptom control, while 11% discontinued amantadine for nonresponse and 6% stopped amantadine because of side effects. Among patients previously receiving other psychotropic medication, 42% and 28% of patients fully discontinued second- or third-generation antipsychotics or antidepressants, respectively. Patients responsive to amantadine who discontinued or reduced antipsychotic dose experienced a significant reduction in body mass index. Amantadine appears be an efficacious and safe alternative for treatment of a broad set of psychiatric symptoms in children and adolescents. Specifically, it may serve as an effective adjunct to stimulants for attention deficit/hyperactivity disorder–related symptoms and appears to be a safer alternative to second- or third-generation antipsychotics.

Water ice exists on many objects in space. The most abundant icy species, among them water, are present in the icy satellites of the outer Solar System giant planets. The nuclei of comets, which are mainly composed of water ice, give another example of its abundance. In the interstellar medium (ISM), ice mantles, formed by molecular species sticking on dust grains, consist mainly of water ice. All these objects are exposed to ionizing radiation like ions, UV photons, and electrons. Sputtering of atoms, molecules, ions, and radicals from icy surfaces may populate and maintain exospheres of icy objects in the Solar System. In other respects, ionized hydrides such as OH+, H2O+, and H3O+have been detected in the gas phase in star-forming regions. Interactions with cosmic rays could be an additional explanation to the current models for the formation of those species. In fact, laboratory simulations showed that the main components of the sputtered ionic species from water ice are oxygen hydrides. In this work, water ice targets were irradiated at several temperatures (10–200 K) by 90 keV O6+ions, yielding an electronic stopping power of about 12 eV/Å, when the nuclear stopping power is comparable to the electronic stopping power. Sputtering of secondary ions after bombardment of the ice target was analyzed by time-of-flight mass spectrometry (TOF-SIMS). Besides hydrogen ions (H+, H2+, H3+), also O+, O2+, OH+, (H2O)+, and clusters of (H2O)nH+with n= 1–8 are emitted. Our results show a progressive yield decrease with increasing temperature of all of the detected species. This is related to the structure of the ice: the ionic sputtering yield for crystalline ice is much lower than for an amorphous ice. For instance, amorphous ice at 10 K exhibits a yield of the order of 2 × 10–6secondary (H2O)nH+hydride ions/projectile (with n= 1–8). As the temperature is increasing toward the phase transition to crystalline ice, the yields decrease by about one order of magnitude.

Context. Ices present in different astrophysical environments are exposed to ion irradiation from cosmic rays (H to heavier than Fe) in the keV to GeV energy range.

Une source d'ions de recul, destinée à la réalisation d'expériences de collisions d'ions multichargés de très basse énergie, a été mise au point et testée sur la SME (Sortie à Moyenne Energie) du GANIL (Grand Accélérateur National d'lons Lourds). L'efficacité des faisceaux de la SME pour la production d'ions de recul d'argon de hauts états de charge est mise en évidence (plus de 104ions Ar15+obtenus par seconde pour un faisceau d'ions projectiles de 300 nA d'ions Xe39+de 4,7 MeV/A). Il est de plus démontré que les faisceaux produits par cette source peuvent être décélérés jusqu'à des énergies de l'ordre de quelques qeV sans perte importante d'intensité ni de qualité.

As of early 2022, only six species bearing an N–O bond have been detected toward cold molecular clouds and regions of star formation. It is not clear yet if the small number of N–O bond species found in the interstellar medium so far stems from physical and technological limitations of astronomical detection techniques, or whether in fact molecules that bear an N–O bond are for some reason rare in these objects of the interstellar medium. Astronomical N–O bearing molecules are important because they are part of astrochemical models which propose that they are precursors of hydroxylamine (NH2OH), a species linked to the formation of prebiotic amino acids in space. The aim of this study is the better understanding of the open question of the interstellar synthesis of N–O bearing species. We have analyzed by infrared spectroscopy an astrophysically relevant polar ice mixture of N2O:H2O processed by 90 MeV 136Xe23+ions, which can mimic the physicochemical processes triggered by cosmic rays in water-covered interstellar ice grains. The results show the formation of N2O3and of H2O2, but no HN–O species of any kind were detected. Such findings are discussed in light of recent studies from our group and from the literature.

The design and synthesis of star polycaprolactone−hydroxyapatite films for use as a biodegradable matrix for bone tissue engineering will be presented. mPEG-dendritic-poly(l-lysine) terminated with glycolic acid residues serve as the star polymer cores for attachment of polycaprolactone by ring-opening polymerization of ε-caprolactone. Initial studies involved testing physical blends of the tert-butoxycarbonyl (Boc) and glycolamide terminated dendrons, generations zero through six, with varying concentrations of hydroxyapatite (HA). The star polymer had not only drastically different solubility but also greatly improved film quality. Further improvements were made in film quality and homogeneity by utilizing the star polymers in the presence of a chemical synthesis of hydroxyapatite. The improved films were then tested for their mechanical strength properties. The star polymer from generation 6.5 and 20 wt % of hydroxyapatite exhibited good mechanical properties with an average Young's modulus of 1.77 MPa, tensile strength of 4.19 MPa, and ultimate elongation of 19%. The details of the chemical synthesis of hydroxyapatite in the presence of the star polymer are discussed.

N‐alkyl‐N‐vinylformamide monomers (alkyl: n‐butyl, hexyl, decyl, and dodecyl) are synthesized in two steps: first, preparation of N‐vinylformamide potassium salt by the reaction of N‐vinylformamide (NVF) with potassium t‐butoxide, then reaction with alkyl bromide. All four monomers are liquid and are characterized by IR, 1H NMR, 13C NMR, and mass spectra. They exist as rotomers in solution and a 2D NOE experiment on the N‐hexyl containing polymer shows the E isomer to be favored. The polymerizability of the four monomers is from good to fair, depending upon the length of alkyl chain on the N‐atom‐‐the longer the chain length, the lower lower the polymerizability of monomer. The hydrolysis of poly(N‐hexyl‐N‐vinylformamide) and poly(N‐dodecyl‐N‐vinylformamide) under acidic and basic conditions was examined. Studies show that hydrolytic cleavage of formyl groups of poly (N‐alkylated‐N‐vinylformamide) depends on the hydrophobicity of the alkyl substituent on the N‐atom under acidic conditions; both polymers were hydrolyzed to only a minor extent under alkaline conditions. The N‐alkylated monomers can copolymerize with NVF and demonstrate amphiphilic properties. The copolymers demonstrate a critical aggregation concentration above which they can solubilize a water insoluble dye; the N‐hexyl containing copolymer stabilizes a castor oil‐in‐water emulsion. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4994–5004, 2004

The synthesis, polymerization, and copolymerization of a new cyclic ester, γ-(2-bromo-2-methyl propionyl)-ε-caprolactone (3), containing a pendent-activated alkyl bromide functional group is described. This new compound serves as both a monomer for “living” ring-opening polymerization (ROP) as well as an initiator for the controlled atom transfer radical polymerization (ATRP). Three distinctive routes to poly(ε-caprolactone)−graft−poly(methyl methacrylate) copolymers were surveyed by either sequential or concurrent living polymerization procedures. The first approach involves the ROP of ε-caprolactone with various compositions of 3, followed by the polymerization of methyl methacrylate via ATRP from the activated alkyl bromide sites along the polyester backbone. Alternatively, α-lactone functional methyl methacrylate macromonomers were prepared by ATRP of methyl methacrylate initiated from 3. The macromonomers were copolymerized with ε-caprolactone via ROP to form the target graft copolymers. Finally, the graft copolymers could be prepared in a simple one-step approach by the concurrent polymerization of ε-caprolactone, 3, and methyl methacrylate together with the appropriate initiator for the ROP and the catalyst for the ATRP. The new monomer enabled new graft copolymers having an aliphatic polyester backbone with poly(methyl methacrylate) grafts of controlled molecular weight and narrow polydispersities (~1.3).

Laboratory data of CH4ice radiolysis promoted by fast heavy ions are obtained by infrared spectroscopy (FTIR). CH4molecules are condensed on a CsI substrate at 15 K, and the ice layer is bombarded by 220 MeV 16O7+ion beam. The ice thickness is thin enough to be traversed by projectiles at constant velocity close to the equilibrium charge state. The induced CH4dissociation gives rise to the formation of molecular species CH3, C2H2, C2H4, C2H6, and C3H8. Their formation and dissociation cross sections are determined. C2H6represent the most abundant daughter molecules. The carbon budget analysis of CH4and its radiolysis products shows that the column density of carbon atoms contained in the methane destroyed during ion irradiation is 30 − 50% greater than the sum for the column densities of the newly formed species. As an astrophysical implication, the current results allow estimation of chemical reaction rates in ices covering interstellar grains.

An experimental study of the interaction of heavy, highly charged, and energetic ions (52 MeV 58Ni13+) with pure H2O, pure CO2and mixed H2O:CO2astrophysical ice analogs is presented. This analysis aims to simulate the chemical and the physicochemical interactions induced by heavy cosmic rays inside dense and cold astrophysical environments, such as molecular clouds or protostellar clouds. The measurements were performed at the heavy ion accelerator GANIL (Grand Accélérateur National d’Ions Lourds in Caen, France). The gas samples were deposited onto a CsI substrate at 13 K. In-situ analysis was performed by a Fourier transform infrared (FTIR) spectrometer at different fluences. Radiolysis yields of the produced species were quantified. The dissociation cross sections of pure H2O and CO2ices are 1.1 and 1.9  × 10-13cm2, respectively. For mixed H2O:CO2(10:1), the dissociation cross sections of both species are about 1  ×  10-13cm2. The measured sputtering yield of pure CO2ice is 2.2  ×  104molec ion-1. After a fluence of 2−3  ×  1012ions cm-2, the CO2/CO ratio becomes roughly constant (~0.1), independent of the initial CO2/H2O ratio. A similar behavior is observed for the H2O2/H2O ratio, which stabilizes at 0.01, independent of the initial H2O column density or relative abundance.

Context. Within dense interstellar clouds, from their periphery to regions deep inside, ice mantles on dust grains are exposed to cosmic-ray irradiation. Various swift ions contribute from protons to iron in the keV to TeV energy range. Observations show that in some lines of sight condensed CO molecules are an important component of the ice.Aims. We irradiate CO ices with Ni ions of relatively high energy (50 and 537 MeV) to simulate the effects produced by fast heavy cosmic-ray ions in interstellar grain mantles.Methods. CO gas is condensed on a CsI substrate at 13 K and irradiated by 50 MeV 58Ni13+and 537 MeV 64Ni24+ions up to a final fluence of ≈1 × 1013cm-2, at a flux of 1 × 109cm-2s-1. The sputtering yields, the destruction rate of CO, and the rate of formation of new molecular species are measured in situ by Fourier transform infrared spectroscopy (FTIR).Results. The measured CO destruction cross-sections and sputtering yields induced by Ni ions are, respectively, (i) for 50 MeV, $\sigma_{\rm d}$= 1.0 × 10-13cm2and Y= 7 × 104molecules/impact; (ii) for 537 MeV, $\sigma_{\rm d}$= 3.0 × 10-14cm2and Y= 5.85 × 104molecules/impact. Based on the present and previous results, the desorption rates induced by H, Ni, and Fe ions are estimated for a wide range of energies. The contribution of the heavy ions is found to dominate over that of protons in the interstellar medium.

Context. Within dense interstellar clouds, from their periphery to regions deep inside, ice mantles on dust grains are exposed to cosmic-ray irradiation. Various swift ions contribute from protons to iron in the keV to TeV energy range. Observations show that in some lines of sight condensed CO molecules are an important component of the ice.

Deep inside dense molecular clouds and protostellar disks, interstellar ices are protected from stellar energetic UV photons. However, X-rays and energetic cosmic rays can penetrate inside these regions triggering chemical reactions, molecular dissociation, and evaporation processes. We present experimental studies of the interaction of heavy, highly charged, and energetic ions (46 MeV 58Ni13+) with ammonia-containing ices H2O:NH3(1:0.5) and H2O:NH3:CO (1:0.6:0.4) in an attempt to simulate the physical chemistry induced by heavy-ion cosmic rays inside dense astrophysical environments. The measurements were performed inside a high vacuum chamber coupled to the IRRSUD (IR radiation SUD) beamline at the heavy-ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a polished CsI substrate previously cooled to 13 K. In-situ analysis was performed by a Fourier transform infrared spectrometer (FTIR) at different fluences. The average values of the dissociation cross-section of water, ammonia, and carbon monoxide due to heavy-ion cosmic ray analogs are ~$2 \times 10^{-13}$, $1.4 \times 10^{-13}$, and $1.9 \times 10^{-13}$cm2, respectively. In the presence of a typical heavy cosmic ray field, the estimated half life of the studied species is 2–$3 \times 10^6$years. The ice compaction (micropore collapse) produced by heavy cosmic rays seems to be at least 3 orders of magnitude higher than that produced by (0.8 MeV) protons. The infrared spectra of the irradiated ice samples exhibit lines of several new species including HNCO, N2O, OCN-, and NH$_4^+$. In the case of the irradiated H2O:NH3:CO ice, the infrared spectrum at room temperature contains five bands that are tentatively assigned to vibration modes of the zwitterionic glycine (NH$_3^+$CH2COO-).

Deep inside dense molecular clouds and protostellar disks, interstellar ices are protected from stellar energetic UV photons. However, X-rays and energetic cosmic rays can penetrate inside these regions triggering chemical reactions, molecular dissociation, and evaporation processes. We present experimental studies of the interaction of heavy, highly charged, and energetic ions (46 MeV 58Ni13+) with ammonia-containing ices H2O:NH3(1:0.5) and H2O:NH3:CO (1:0.6:0.4) in an attempt to simulate the physical chemistry induced by heavy-ion cosmic rays inside dense astrophysical environments. The measurements were performed inside a high vacuum chamber coupled to the IRRSUD (IR radiation SUD) beamline at the heavy-ion accelerator GANIL (Grand Accelerateur National d'Ions Lourds) in Caen, France. The gas samples were deposited onto a polished CsI substrate previously cooled to 13 K. In-situ analysis was performed by a Fourier transform infrared spectrometer (FTIR) at different fluences. The average values of the dissociation cross-section of water, ammonia, and carbon monoxide due to heavy-ion cosmic ray analogs are ~$2 \times 10^{-13}$, $1.4 \times 10^{-13}$, and $1.9 \times 10^{-13}$cm2, respectively. In the presence of a typical heavy cosmic ray field, the estimated half life of the studied species is 2–$3 \times 10^6$years. The ice compaction (micropore collapse) produced by heavy cosmic rays seems to be at least 3 orders of magnitude higher than that produced by (0.8 MeV) protons. The infrared spectra of the irradiated ice samples exhibit lines of several new species including HNCO, N2O, OCN-, and NH$_4^+$. In the case of the irradiated H2O:NH3:CO ice, the infrared spectrum at room temperature contains five bands that are tentatively assigned to vibration modes of the zwitterionic glycine (NH$_3^+$CH2COO-).