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The crystal structures of cefdinir and cefdinir sesquihydrate have been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Cefdinir crystallizes in space group P21 (#4) with a = 5.35652(4), b = 19.85676(10), c = 7.57928(5) Å, β = 97.050(1) °, V = 800.061(6) Å3, and Z = 2. Cefdinir sesquihydrate crystallizes in space group C2 (#5) with a = 23.98775(20), b = 5.01646(3), c = 15.92016(12) Å, β = 109.4470(8) °, V = 1806.438(16) Å3, and Z = 4. The cefdinir molecules in the anhydrous crystal structure and sesquihydrate have very different conformations. The two conformations are similar in energy. The hydrogen bonding patterns are very different in the two structures, and the sesquihydrate is more stable than expected from the sum of the energies of cefdinir and cefdinir sesquihydrate, the result of additional hydrogen bonding. The powder patterns are included in the Powder Diffraction File™ as entries 00-066-1604 (cefdinir) and 00-066-1605 (cefdinir sesquihydrate).
The crystal structures of (NH4)H2C6H5O7 and (NH4)3C6H5O7 have been determined using a combination of powder and single crystal techniques. The structure of (NH4)2HC6H5O7 has been determined previously by single crystal diffraction. All three structures were optimized using density functional techniques. The crystal structures are dominated by N-H⋅⋅⋅O hydrogen bonds, though O-H⋅⋅⋅O hydrogen bonds are also important. In (NH4)H2C6H5O7 very strong centrosymmetric charge-assisted O-H-O hydrogen bonds link one end of the citrate into chains along the b-axis. A more-normal O-H⋅⋅⋅O hydrogen bond links the other end of the citrate to the central ionized carboxyl group. In (NH4)2HC6H5O7, the very strong centrosymmetric O-H-O hydrogen bonds link the citrates into zig-zag chains along the b-axis. The citrates occupy layers parallel to the bc plane, and the ammonium ions link the layers through N-H⋅⋅⋅O hydrogen bonds. In (NH4)3C6H5O7, the hydroxyl group forms a hydrogen bond to a terminal carboxylate, and there is an extensive array of N-H⋅⋅⋅O hydrogen bonds. The energies of the density functional theory-optimized structures lead to a correlation between the energy of an N-H⋅⋅⋅O hydrogen bond and the Mulliken overlap population: E(N-H⋅⋅⋅O) (kcal/mole) = 23.1(overlap)½. Powder patterns of (NH4)H2C6H5O7 and (NH4)3C6H5O7 have been submitted to International Centre for Diffraction Data for inclusion in the powder diffraction file.
The crystal structure of minocycline hydrochloride dihydrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Minocycline hydrochloride dihydrate crystallizes in space group P212121 (#19) with a = 7.40772(1), b = 14.44924(3), c = 22.33329(4) Å, V = 2390.465(12) Å3, and Z = 4. The minocycline cation is a zwitterion: both dimethylamino groups are protonated and one hydroxyl group is ionized. A potential ambiguity in the orientation of the amide group was resolved by considering Rietveld refinement residuals and displacement coefficients, as well as DFT energies. The crystal structure is dominated by hydrogen bonds. Both water molecules and a hydroxyl group act as donors to the chloride anion. Both protonated dimethyl amine groups act as donors to the ionized hydroxyl group. Several intramolecular O–H···O hydrogen groups help determine the conformation of the cation. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1606.
The crystal structure of vardenafil hydrochloride trihydrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Vardenafil hydrochloride trihydrate crystallizes in space group C2/c (#15) with a = 34.78347(16), b = 11.56752(4), c = 14.69308(5) Å, β = 93.3410(4), V = 5901.839(30) Å3, and Z = 8. The fused ring system and the phenyl ring are nearly co-planar; the interplanar angle between them is 6.0°. Two intramolecular hydrogen bonds help determine this conformation. These planes stack along the c-axis. The side chains of these ring systems have a large Uiso and are neighbors in the stacks. Along the a-axis, these stacks are separated by hydrophilic layers of chloride, water molecules, and the positively charged nitrogen atoms of the vardenafil cation. Hydrogen bonds are prominent in the crystal structure. The protonated nitrogen atom forms a strong hydrogen bond to the chloride anion. The water molecules form a hexagon, making hydrogen bonds with themselves, as well as the C1 and a ring nitrogen atom. These discrete hydrogen bonds form a cluster, and there is no extended hydrogen bond network. There are many C–H⋯Cl, C–H⋯O, and C–H⋯N hydrogen bonds, which (although individually weak) contribute significantly to the crystal energy. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1620.
The crystal structure of bretylium tosylate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Bretylium tosylate crystallizes in space group C2/c (#15) with a = 32.6238(4), b = 12.40353(14), c = 9.93864(12) Å, β = 101.4676(10), V = 3941.39(5) Å3, and Z = 8. The sample exhibited visible decomposition in the X-ray beam. The unusual displacement ellipsoid of the Br atom probably indicates that the decomposition in the beam involves the Br atom. The crystal structure can be viewed as layered parallel to the bc plane. The layers are double, the center consisting of the cation/anion polar interactions and the outer surface of the double layers consists of hydrocarbon interactions. In the absence of normal hydrogen bond donors, the only hydrogen bonds in the bretylium tosylate structure are C–H…O hydrogen bonds. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.
The crystal structure of terazosin hydrochloride dihydrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Terazosin hydrochloride dihydrate crystallizes in space group P-1 (#2) with a = 10.01402(4), b = 10.89995(4), c = 11.85357(4) Å, α = 89.5030(3), β = 71.8503(3), γ = 66.5632(2)°, V = 1118.143(8) Å3, and Z = 2. The terazosin cation occurs in an extended conformation. The crystal structure is dominated by hydrogen bonds. The most notable are the O–H···Cl from the water molecules to the chloride anion and N–H···Cl from the protonated ring nitrogen to the chloride. The amino group donates protons to each of the two water molecules. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.
Background: Surgical treatment of trigeminal neuralgia (TN) can be highly effective, but durability of pain relief varies and factors influencing surgical failure are poorly understood. We hypothesized that structural brain differences—assessed using magnetic resonance imaging (MRI)—might distinguish surgical responders from early non-responders. Methods: We retrospectively identified 35 TN patients treated surgically from 2005-2017 with high-resolution, -pre-operative MRI scans adequate for quantitative structural analysis. Patients were classified as non-responders if, within 12-months after surgery, they: 1) underwent or were offered another surgical procedure; or 2) reported persistent, inadequately-controlled pain. Volumes of pain-relevant subcortical structures (amygdala, thalamus, and hippocampus) were measured on T1-weighted MRI scans using an automated approach (FSL-FIRST). Results: Surgical responders had significantly larger hippocampi bilaterally compared to early non-responders. Thalamus and amygdala volumes did not differ between groups. Conclusions: Pre-operative differences in brain structure, notably in the hippocampus, may predict durability of response to surgery in patients with TN.
Background: Temporal lobe epilepsy (TLE) accounts for approximately 20% of pediatric epilepsy cases. Of those, many are considered medically intractable and require surgical interventions. In this study, we hypothesized that mesial temporal sclerosis (MTS) was less common in patients who had undergone surgery for intractable pediatric TLE than in adult series. We further hypothesized that there was a radiological and pathological discordance in identifying the cause of pediatric TLE. Methods: We retrospectively reviewed the charts of pediatric patients with TLE who had undergone surgical treatments as part of the University of Alberta’s Comprehensive Epilepsy Program between 1988 and 2018. Along with preoperative magnetic resonance imaging (MRI) reports, post-surgical pathology results and seizure outcomes were studied Results: Of the 83 pediatric patients who had undergone temporal lobe epilepsy surgery, 28% had tumors, 22% had dual pathologies, 18% had MTS, 11% had focal cortical dysplasia, and 22% had other pathologies. In addition, for 36% of these patients, discordance between their pre-surgical MRI reports and post-surgical pathology reports were found. Conclusions: This was one of the largest retrospective cohort studies of pediatric patients who had undergone surgery for intractable TLE. This study showed that tumors, and not MTS, were the most common pathology in surgical pediatric TLE.
Estradiol valerate (brand name: Delestrogen) is used as a hormone replacement therapy for menopause symptoms and for treating advanced prostate cancer. Commercial estradiol 17β valerate crystallizes in the monoclinic space group P21 with a = 7.36787(3), b = 19.84900(6), c = 13.99395(10) Å, β = 90.6845(5)°, V = 2046.398(18) Å3, and Z = 4.
The crystal structure of methylprednisolone acetate form II, C24H32O6, has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Methylprednisolone acetate crystallizes in space group P212121 (#19) with a = 8.17608(2), b = 9.67944(3), c = 26.35176(6) Å, V = 2085.474(6) Å3, and Z = 4. Both hydroxyl groups act as hydrogen bond donors, resulting in a two-dimensional hydrogen bond network in the ab plane. C–H⋯O hydrogen bonds also contribute to the crystal energy. The powder pattern is included in the Powder Diffraction File™ as entry 00-065-1412.
The Berkeley Visible Image Tube (BVIT) has been a user instrument on the SALT 10-m telescope for the past six years. It can observe transient astrophysical phenomena occurring on time-scales of micro-seconds. This overview presented some recent observations of a dMe flare star, and discussed the recent results of our optical Search for Extraterrestrial Intelligence (OSETI) around nearby exoplanet-hosting stars.
The yields of spring barley during a medium-term (7 years) compost and slurry addition experiment and the soil carbon (C) and nitrogen (N) contents, bacterial community structure, soil microbial biomass and soil respiration rates have been determined to assess the effects of repeated, and in some cases very large, organic amendments on soil and crop parameters. For compost, total additions were equivalent to up to 119 t C/ha and 1·7 t N/ha and for slurry they were 25 t C/ha and 0·35 t N/ha over 7 years, which represented very large additions compared to control soil C and N contents (69 t C/ha and 0·3 t N/ha in the 0–30 cm soil depth). There was an initial positive response to compost and slurry addition on barley yield, but over the experiment the yield differential between the amounts of compost addition declined, indicating that repeated addition of compost at a lower rate over several years had the same cumulative effect as a large single compost application. By the end of the experiment it was clear that the addition of compost and slurry increased soil C and N contents, especially towards the top of the soil profile, as well as soil respiration rates. However, the increases in soil C and N contents were not proportional to the amount of C and N added, suggesting either that: (i) a portion of the added C and N was more vulnerable to loss; (ii) that its addition rendered another C or N pool in the soil more susceptible to loss; or (iii) that the C inputs from additional crop productivity did not increase in line with the organic amendments. Soil microbial biomass was depressed at the highest rate of organic amendment, and whilst this may have been due to genuine toxic or inhibitory effects of large amounts of compost, it could also be due to the inaccuracy of the substrate-induced respiration approach used for determining soil biomass when there is a large supply of organic matter. At the highest compost addition, the bacterial community structure was significantly altered, suggesting that the amendments significantly altered soil community dynamics.
Background: Temporal Lobe Epilepsy is associated with bilateral gray (GM) and white matter (WM) loss. After surgical treatment progressive bilateral temporal and extra-temporal WM change occur, however, less is known regarding post-operative GM change. We set out to measure contralateral hippocampal volume (CHV) following TLS. Methods: 1.5T-3D-1mm-isotropic-MPRAGE scans in 26 TLE patients and 3 controls in two groups: longitudinal (n=10)(imaged POD1,2,3,6,60,120 and >360d) and single post-operative scan (n=16). Manual volumetry protocols. Results: We find significant CHV atrophy at delayed scan relative to baseline (mean atrophy 26.8%). In the longitudinal group there is significant and progressive atrophy from baseline to POD4-8 (72.6+/-6.5%), POD60-360 (69.7+/-12.3%) and >360 (58.5+/-10.6%). No significant atrophy in either the control group HV or contralateral CV over time. No significant difference in mean HV at the most delayed exam for surgery type (p=0.13) or side (p=0.24). Conclusions: We find a statistically significant CHV atrophy following surgery which is progressive over time. Our longitudinal within-subject design describes the time course and extent more fully than previous work. Caudate analysis indicates that early CHV atrophy is not due to global atrophy following brain surgery but rather may be due to deafferentation and deefferentation. Finally, we find no significant difference in atrophy when analyzed by surgical approach or surgical side.
Background: Dysembryoblastic neuroepithelial tumors (DNETs) are benign tumors of the cerebral cortex that most commonly occur in children or young adults. Seizures are a frequent presenting feature, with an incidence of 80-100%, and are often an indication for surgical resection. Methods: We performed a retrospective chart review of children with DNETs who underwent epilepsy surgery between 1998 and 2014. Results: A total of 12 subjects were identified (6 males, 6 females), all of whom had seizures prior to surgical resection. Of these patients, 1 had infantile spasms, 2 had simple partial seizures and 10 had complex partial seizures. Tumors were located in the temporal (n=7), frontal (n=3) or parietal (n=2) cortex. These patients went on to have surgery on average 15 months after seizure onset, 3 had incomplete resections. At an average follow up of 6 years 4 months, all patients were class 1 on Engel’s Classification. All but one subject with rare non-disabling seizures were seizure free, with only 6 on medication. Follow up MR imaging revealed tumor recurrence in 1 subject. Conclusions: Despite differing seizure seminology and tumor location, surgical resection of these low-grade tumors resulted in excellent seizure outcome even in the setting of incomplete tumor resection.
This paper brings together the work of the GI Solvency II Technical Provisions working party. The working party was formed in 2009 for the primary purpose of raising awareness of Solvency II and the impact it would have on the work that reserving actuaries do. Over the years, the working party’s focus has shifted to exploring and promoting discussion of the many practical issues raised by the requirements and to promoting best practice. To this end, we have developed, presented and discussed many of the ideas contained in this paper at events and forums. However, the size of the subject means that at no one event have we managed to cover all of the areas that the reserving actuary needs to be aware of. This paper brings together our thinking in one place for the first time. We hope experienced practitioners will find it thought provoking, and a useful reference tool. For new practitioners, we hope it helps to get you up-to-speed quickly. Good luck!
Anorexia nervosa (AN) is a serious disorder incurring high costs due to hospitalization. International treatments vary, with prolonged hospitalizations in Europe and shorter hospitalizations in the USA. Uncontrolled studies suggest that longer initial hospitalizations that normalize weight produce better outcomes and fewer admissions than shorter hospitalizations with lower discharge weights. This study aimed to compare the effectiveness of hospitalization for weight restoration (WR) to medical stabilization (MS) in adolescent AN.
We performed a randomized controlled trial (RCT) with 82 adolescents, aged 12–18 years, with a DSM-IV diagnosis of AN and medical instability, admitted to two pediatric units in Australia. Participants were randomized to shorter hospitalization for MS or longer hospitalization for WR to 90% expected body weight (EBW) for gender, age and height, both followed by 20 sessions of out-patient, manualized family-based treatment (FBT).
The primary outcome was the number of hospital days, following initial admission, at the 12-month follow-up. Secondary outcomes were the total number of hospital days used up to 12 months and full remission, defined as healthy weight (>95% EBW) and a global Eating Disorder Examination (EDE) score within 1 standard deviation (s.d.) of published means. There was no significant difference between groups in hospital days following initial admission. There were significantly more total hospital days used and post-protocol FBT sessions in the WR group. There were no moderators of primary outcome but participants with higher eating psychopathology and compulsive features reported better clinical outcomes in the MS group.
Outcomes are similar with hospitalizations for MS or WR when combined with FBT. Cost savings would result from combining shorter hospitalization with FBT.
This study aimed to assess the speed of referral, diagnosis and treatment of patients with lymphoma presenting with a neck lump, and to identify where delays are occurring that prevent UK national targets from being met.
The study entailed a retrospective survey of patients presenting with a neck lump secondary to lymphoma between 2006 and 2008 in Gloucestershire, UK.
Forty-seven of 54 patients (87 per cent) were seen within 2 weeks of referral. However, the 62-day rule, which covers the time from referral to the initiation of treatment, was met in only 32 of the 54 cases (59 per cent). There were no breaches of the 31-day target, which concerned the time from decision to treat to the initiation of treatment. Subsequent target breaches were due to longer waiting times for radiological and pathological investigations.
Radiological examinations should be ordered at the first consultation and biopsies performed as soon as possible. Establishing one-stop, rapid access clinics should improve the achievement of a maximum 62-day wait for patients with lymphoma presenting with neck lumps.
The Next Generation Transit Survey (NGTS) is a new ground-based survey for transiting exoplanets. Our primary goal is to find the first statistically-significant sample of Neptunes and super-Earths that are bright enough for radial velocity confirmation. By measuring precise masses and radii we will constrain the bulk composition and internal structure of planets that span the transition between the gas giants and terrestrial planets. Our brightest exoplanets will also be suitable for atmospheric characterisation with large facilities such as the VLT, JWST and the E-ELT. NGTS construction began in June 2013, and the survey is due to commence in 2014.