Flexible metal-organic frameworks.

Advances in flexible and functional metal-organic frameworks (MOFs), also called soft porous crystals, are reviewed by covering the literature of the five years period 2009-2013 with reference to the early pertinent work since the late 1990s. Flexible MOFs combine the crystalline order of the underlying coordination network with cooperative structural transformability. These materials can respond to physical and chemical stimuli of various kinds in a tunable fashion by molecular design, which does not exist for other known solid-state materials. Among the fascinating properties are so-called breathing and swelling phenomena as a function of host-guest interactions. Phase transitions are triggered by guest adsorption/desorption, photochemical, thermal, and mechanical stimuli. Other important flexible properties of MOFs, such as linker rotation and sub-net sliding, which are not necessarily accompanied by crystallographic phase transitions, are briefly mentioned as well. Emphasis is given on reviewing the recent progress in application of in situ characterization techniques and the results of theoretical approaches to characterize and understand the breathing mechanisms and phase transitions. The flexible MOF systems, which are discussed, are categorized by the type of metal-nodes involved and how their coordination chemistry with the linker molecules controls the framework dynamics. Aspects of tailoring the flexible and responsive properties by the mixed component solid-solution concept are included, and as well examples of possible applications of flexible metal-organic frameworks for separation, catalysis, sensing, and biomedicine.

MOF thin films: existing and future applications.

The applications and potentials of thin film coatings of metal-organic frameworks (MOFs) supported on various substrates are discussed in this critical review. Because the demand for fabricating such porous coatings is rather obvious, in the past years several synthesis schemes have been developed for the preparation of thin porous MOF films. Interestingly, although this is an emerging field seeing a rapid development a number of different applications on MOF films were either already demonstrated or have been proposed. This review focuses on the fabrication of continuous, thin porous films, either supported on solid substrates or as free-standing membranes. The availability of such two-dimensional types of porous coatings opened the door for a number of new perspectives for functionalizing surfaces. Also for the porous materials themselves, the availability of a solid support to which the MOF-films are rigidly (in a mechanical sense) anchored provides access to applications not available for the typical MOF powders with particle sizes of a few µm. We will also address some of the potential and applications of thin films in different fields like luminescence, QCM-based sensors, optoelectronics, gas separation and catalysis. A separate chapter has been devoted to the delamination of MOF thin films and discusses the potential to use them as free-standing membranes or as nano-containers. The review also demonstrates the possibility of using MOF thin films as model systems for detailed studies on MOF-related phenomena, e.g. adsorption and diffusion of small molecules into MOFs as well as the formation mechanism of MOFs (101 references).

Merging molecular catalysts and metal-organic frameworks for photocatalytic fuel production.

In the effort to generate sustainable clean energy from abundant resources such as water and carbon dioxide, solar fuel production-the combination of solar-light harvesting and the generation of efficient chemical energy carriers-by artificial molecular photosystems is very attractive. Molecular constituents that display attractive features for chemical energy conversion (such as high product selectivity and atom economy) have been developed, and their interfacing with host materials has enabled recyclability, controlled site positioning, as well as access to fundamental insights into the catalytic mechanism and environment-governed selectivity. Among the wide variety of supports, metal-organic frameworks (MOFs) possess valuable characteristics (such as their porosity and versatility) that can influence the reaction environment and material architecture in a unique fashion. Here we highlight the various existing synthetic strategies to graft molecular complexes such as catalysts and photosensitizers onto MOFs for solar fuel production. The opportunities and limitations of one-pot and stepwise approaches are critically assessed, and the resulting materials are discussed based on their photocatalytic performances and the practical applicability of selected examples.

Cultivar × Management Interaction to Reduce Lodging and Improve Grain Yield of Irrigated Spring Wheat: Optimising Plant Growth Regulator Use, N Application Timing, Row Spacing and Sowing Date.

Severe lodging of irrigated spring-wheat in sub-tropical Australia has previously caused yield loss of between 1.7 and 4.6 t ha-1 (20-60% of potential yield). In response, agronomic management options were assessed for their ability to reduce lodging and increase grain yield, namely plant growth regulators (PGRs), timing of nitrogen (N) application, row spacing and sowing date, in combination with long and short duration cultivars across 15 irrigated environments from 2012 to 2016. Our study identified significant interaction between genotype, environment and agronomic management (G × E × M) for grain yield and lodging, although some combinations of agronomic techniques were broadly applicable across cultivars. PGR application improved grain yield of most cultivars in well-irrigated fields that had more than 120 kg ha-1 N (mineral N + fertiliser N) at sowing, with yield gains of up to 0.5 t ha-1 observed in both lodged and non-lodged fields. However, PGRs had little effect on grain yield when soil + fertiliser N at sowing was less than 80 kg ha-1 N. In-crop N application (compared to sowing N application) often improved grain yield of short duration, lodging resistant cultivars, but reduced the yield of long-duration, lodging susceptible cultivars in some environments. Narrow row spacing of 19 cm had the highest grain yield across cultivars in low lodging environments. At a severely lodged environment, narrow rows were the highest yielding for five out of six cultivars when PGRs were used, but was the highest yielding for only half of the tested cultivars when PGRs were not used. Cultivar × sowing date interaction for grain yield was also associated with the occurrence of lodging. Neither early nor late sowing had a consistent yield benefit across a range of cultivars, as lodging severity varied between sowing date depending on the timing of storm-induced lodging events. Lodging resistant long-duration cultivars had more stable grain yield across environments and increased grain yield in response to early sowing. Further research is needed to determine the optimum management strategy for new cultivars, because farmers do not always choose the most lodging resistant cultivars for reasons of cultivar disease resistance, grain quality and seed availability.

Stomatal opening: role of potassium uptake by guard cells.

Stomata in isolated epidermal strips open in response to light plus air free of carbon dioxide when the strips are floated on potassium chloride solutions of low concentrations. This opening depends on the stimulation of active accumulation of potassium in quantities sufficient to account for the observed changes in solute potential of the guard cells.

Review: High-throughput phenotyping to enhance the use of crop genetic resources.

Improved genetic, genomic and statistical technologies have increased the capacity to enrich breeding populations for key alleles underpinning adaptation and continued genetic gain. In turn, directed genomic selection together with increased heritability will reduce genetic variance to narrow the genetic base in many crop breeding programs. Diverse genetic resources (GR), including wild and weedy relatives, landraces and reconstituted synthetics, have potential to contribute novel alleles for key traits. Targeted trait identification may also identify genetic diversity in addressing new challenges including the need for modified root architecture, greater nutrient-use efficiency, and adaptation to warmer air and soil temperatures forecast with climate change. Yet while core collections and other GR sources have historically been invaluable for major gene control of disease and subsoil constraints, the mining of genetically (and phenotypically) complex traits in GR remains a significant challenge owing to reduced fertility, limited seed quantities and poor adaptation through linkage drag with undesirable alleles. High-throughput field phenomics (HTFP) offers the opportunity to capture phenotypically complex variation underpinning adaptation in traditional phenotypic selection or statistics-based breeding programs. Targeted HTFP will permit the reliable phenotyping of greater numbers of GR-derived breeding lines using smaller plot sizes and at earlier stages of population development to reduce the duration of breeding cycles and the loss of potentially important alleles with linkage drag. Two key opportunities are highlighted for use of HTFP in selection among GR-derived wheat breeding lines for greater biomass and stomatal conductance through canopy temperature.

Statutory requirements for disclosure of breast cancer treatment alternatives.

Therapeutic options for breast cancer, particularly for early-stage disease, and increased patient participation in medical decision-making have oriented state legislatures toward ensuring that women with breast cancer have adequate information about treatment alternatives. Currently, 18 states have enacted statutes regarding physician disclosure of treatment alternatives to breast cancer patients. This paper reviews these statutes in the context of the requirements imposed on the physician as health care provider and the content of medical information presented to the patient as a consequence of the laws. State statutes were identified through the National Cancer Institute's State Cancer Legislative Database, and the statutory requirements were analyzed. For statutes requiring development of a written summary of treatment alternatives, the most recent summary was obtained through the responsible state agency, and informational content was analyzed for relevance to treatment decisions in early-stage disease. As a group, these laws address informed consent for treatment, physician behavior within the patient-physician relationship, and the medical information upon which treatment decisions are based. Individual statutes vary in the scope of the issues addressed, particularly in the responsibility placed on physicians, and treatment option summaries developed in response to this legislation vary widely in content and scope. Despite broad implications of these statutes in oncology practice, little is known about their effects on breast cancer care. Additional research is needed to define the impact of these statutes on breast cancer care, as such legislation is considered by other states for this and other diseases.

Histiocytosis X of the vulva: a case report and review of the literature.

Histiocytosis X of the female genital tract is unusual. Thirty-two cases have been reported to date in the world literature. An additional case is reported herein, presenting as a vulvar ulcer in a 2.5-year-old child with osteolytic lesions of the skull, splenomegaly, and otitis media. The diagnosis of histiocytosis X may be established by identifying the Langerhans histiocyte, characterized by nuclear grooves, immunoreactivity for S-100 protein, and pentalamellar cytoplasmic structures seen by electron microscopy. Prognosis is difficult to determine with certainty. However, age of less than 2 years at presentation, multi-organ involvement, and/or organ dysfunction appear to be associated with a less favorable prognosis. The patient presented herein is currently receiving vinblastine chemotherapy for recurrence of disease, manifested as an osteolytic lesion in the skull.

Ovulation after intravenous and intramuscular human chorionic gonadotropin.

OBJECTIVE: To define the time interval from intravenous and intramuscular hCG administration to follicular wall rupture and the endocrinologic events associated with ovulation. DESIGN: Subjects were studied in two cycles and received hCG either 10,000 IU IM or 500 IU IV in a random sequence with an intervening spontaneous menstrual cycle. PATIENTS: Thirty women from the University of Vermont Reproductive Endocrinology Service with unexplained, male, or cervical factor infertility. INTERVENTIONS: Subjects underwent superovulation with clomiphene citrate followed by hCG administration when the lead follicle reached a mean diameter of 18 mm. Follicular rupture was determined by ultrasound monitoring every 2 hours starting 31 and 30 hours after intravenous and intramuscular hCG, respectively. Serum samples were obtained hourly for hormone measurements. The study was completed 2 hours after follicular rupture or 48 hours after hCG administration. RESULTS: Twenty-five subjects received both intramuscular and intravenous hCG. The mean time to ovulation was 40.4 hours after intramuscular hCG (range, < or = 36 to > or = 48 hours) and 38.3 hours after intravenous hCG (range, 33 to > or = 48 hours). No differences were noted in the time interval to ovulation or rate of change in circulating E2 and P levels after IM versus IV hCG administration. CONCLUSIONS: These findings suggest (1) ovulation occurs over a broad range of time after hCG administration; (2) ovulation does not occur in a more specific time interval after intravenous than intramuscular hCG; and (3) the rate of change in circulating E2 and P levels are not different after intravenous than intramuscular hCG.

Episodic acute hypotonia after Nd:YAG laser capsulotomy--retinal function and choroidal swelling.

In a patient with uveitis who had been treated with Nd:YAG laser capsulotomy after cataract surgery, several episodes of acute hypotonia occurred which were associated with changes in clinical tests of the eye and of visual function. Immunosuppressive and immunomodulating treatment appeared to reverse the changes in intraocular pressure and normalise the test results. The significance of these observations is discussed.

Analysis of the effect of using two different strain rates on the acoustic emission in bone.

To study the effect of strain rate on the acoustic emission amplitude signature of bone, bovine cortical bone was milled into standard tensile specimens which were tested at two different strain rates while being monitored with acoustic emission equipment. It was demonstrated that the amplitude distribution of the acoustic events in bone is dependent on strain rate. Greater numbers of events occurred with the slower strain rate (0.0001 s-1), but these events were of lower amplitude than those emitted during the more rapid strain rate (0.01 s-1). The plot of the cumulative event amplitude distribution followed the power-law model, and the slope of this output, the b-value, represented a signature of the amplitude distribution. The mechanical test results were consistent with the behavior of a viscoelastic multi-phase composite material.

Granular cell myoblastomas.

Granular cell myoblastoma is an uncommon benign tumor. The diagnosis is rarely suspected preoperatively, and the clinician is frequently baffled or frightened by an unfamiliar diagnosis. Twenty-eight patients with the diagnosis of granular cell myoblastoma presented for treatment at Richmond Eye and Ear Hospital and the Medical College of Virginia Hospitals between January 1, 1952, and December 31, 1974. The authors believe that this is one of the largest series of cases reported in the world literature. The tumor presents most often in the fourth decade of life and about equally in the sexes. Of interest is the nearly 5:1 predominance in the Negro race compared to the Caucasian race.

Midline foci of epileptiform activity in children and neonates.

We report the clinical and electroencephalographic (EEG) correlates of focal potentially epileptogenic discharge arising from midline sagittal vertices (Fz, Cz, Pz) in 21 children prospectively identified from among 7,051 consecutive EEGs recorded during a 27-month period. The patients range in age from neonates to 13 years. EEGs were obtained during evaluations for solitary or recurrent seizures (17/21), attention deficit disorder (2/21), psychomotor retardation (1/21), and headache (1/21). Clinical seizure types were diverse and included simple partial (5/17), complex partial (2/17), generalized tonic-clonic (4/17), mixed (2/17), and neonatal (4/17). The majority (13/21) of patients had an identifiable etiology for their disorder; CT scans verified mass lesions in two patients. Midline epileptogenic foci were present during wakefulness in 14 of 17 older children and restricted to sleep in the others. Sleep states were indeterminate in the four neonates. Midline foci were exquisitely confined to Fz, Cz, and/or Pz in 6 of 17 older children and would have been entirely missed by a recording montage that did not include vertex electrodes. In five other children, midline foci spread preferentially to the adjacent central-parietal regions and closely resembled the appearance of benign rolandic foci in the longitudinal EEG montages, a potentially serious cause of EEG misinterpretation in view of the high incidence of neuropathology in this patient group.

Transfusion-associated falciparum malaria successfully treated with red blood cell exchange transfusion.

Falciparum malaria is frequently associated with significant morbidity and mortality. The use of exchange transfusion as a therapeutic modality for severe cases of malaria has been described previously. We describe a case of a 49 year-old African American gentleman with a history of hemoglobin-SC disease who presented with a severe case of Plasmodium falciparum malaria 3 weeks after having received an infected blood transfusion. His peripheral smear showed the presence of numerous intraerythrocytic ring forms and "banana-shaped" gametocytes with a high-grade parasitemia, estimated at 18%. He was treated with antimalarial chemotherapy and also underwent a 12-unit red blood cell exchange transfusion, decreasing his parasite load to < 1%, as determined on repeat smear. It is prudent to be aware of the efficacy of this adjunctive treatment, especially with ever-increasing travel and a resultant increase in the prevalence of tropical diseases in the United States.

Arthroscopic distal clavicle resection for isolated atraumatic osteolysis in weight lifters.

Ten consecutive patients with isolated atraumatic osteolysis of the distal clavicle who had failed results with conservative treatment were treated with arthroscopic resection of the involved distal clavicle (average, 4.5 mm). All patients were men with an average age of 30.4 years, had unilateral involvement, and were considered aggressive amateur to elite weight lifters or bodybuilders. Postoperative symptoms consisted of pain at the incision and discomfort from extravasation of the irrigation fluid. At an average followup of 18.7 months, all patients had returned to their sport (average, 3.2 days) and to their preoperative weight training program (average, 9.1 days). They continued to be asymptomatic throughout the follow-up period and were able to increase both their training volume and strength from preoperative levels. Limited arthroscopic resection of the distal clavicle for isolated atraumatic osteolysis is a viable alternative for the weight lifter or bodybuilder. The ability to continue training without significant interruption as well as a more acceptable cosmetic appearance are benefits for these patients. Limited arthroscopic resection of the distal clavicle may be sufficient for this entity in this patient population, rather than the 1 to 2 cm previously reported. A sport-specific functional outcome questionnaire has been developed for this patient population.

The functional relationship of the posterior oblique ligament to the medial collateral ligament of the human knee.

Strain in the human knee medial collateral ligament (MCL) was measured in cadavers with a Hall effect strain transducer during normal passive knee flexion, as well as knee flexion accompanied by applied external tibial rotation and valgus torques. In an attempt to determine the contribution of the posterior oblique ligament (POL) to the strain behavior of the MCL, the POL was systematically separated from the MCL and changes in strain in the MCL were observed. These changes in strain were mild and variable, except in the one knee which was later found to be lacking an anterior cruciate ligament. In that particular knee, strain in the MCL increased up to 9.97% under the influence of a valgus torque once the POL fibers had been separated from the MCL. Anatomical dissection and transillumination techniques of the MCL/POL complex demonstrated definite ligament fibers connecting the MCL to the POL. The results demonstrate an intimate anatomical relationship between the POL and MCL. However, the POL and MCL appear to work independently from each other according to our test method.

The biomechanics of anterior cruciate ligament rehabilitation and reconstruction.

The rehabilitation of knee injuries involving the anterior cruciate ligament (ACL) is controversial. This paper describes strain in the normal and reconstructed ACL during a series of passive and active tests of knee flexion with and without varus, valgus, and axial rotation torques on the tibia. Strain in the human knee ACL was significantly different depending on whether the knee flexion angle was changed passively or via simulated quadriceps contraction. The knee joint capsule was found to be important for strain protection of the ACL. Quadriceps activity did not strain the normal or reconstructed ACL when the knee was flexed beyond 60 degrees, but significantly strained the tissue from 0 to 45 degrees of knee flexion. Immobilization may not protect the ACL if isometric quadriceps contractions are allowed to occur. Properly placed reconstructions exhibited strain behavior which closely followed the anteromedial band of the ACL.

The relationship between anterior-posterior knee laxity and the structural properties of the patellar tendon graft. A study in canines.

We studied the relationship between anterior-posterior knee laxity and the structural properties of autogenous patellar tendon grafts used to replace the anterior cruciate ligaments in dogs 1 year after reconstruction. At 30 degrees (full extension for the dog), 60 degrees, and 90 degrees of flexion a significant inverse correlation was found between anterior-posterior knee laxity and the ultimate failure strength of the graft. Likewise, at 60 degrees and 90 degrees of flexion a significant inverse correlation was found between knee laxity and the linear stiffness of the graft. In all cases, as knee laxity increased, the ultimate failure load and linear stiffness values of the graft were found to decrease. There was also a significant increase in anterior-posterior knee laxity of the reconstructed knees (produced by an increase in anterior translation of the tibia relative to the femur) compared with the contralateral control knee. The group of dogs that underwent a sham operation without reconstruction of the anterior cruciate ligament had no change in anterior-posterior knee laxity or the structural properties of the anterior cruciate ligament. The clinical significance of this investigation is that knee laxity measurements demonstrating an increase in anterior translation of the tibia relative to the femur during graft healing may indicate that the graft has weakened and reduced structural properties.

Co3O4/ZnO nanocomposites: from plasma synthesis to gas sensing applications.

Herein, we describe the design, fabrication and gas sensing tests of p-Co(3)O(4)/n-ZnO nanocomposites. Specifically, arrays of (001) oriented ZnO nanoparticles were grown on alumina substrates by plasma enhanced-chemical vapor deposition (PECVD) and used as templates for the subsequent PECVD of Co(3)O(4) nanograins. Structural, morphological and compositional analyses evidenced the successful formation of pure and high-area nanocomposites with a tailored overdispersion of Co(3)O(4) particles on ZnO and an intimate contact between the two oxides. Preliminary functional tests for the detection of flammable/toxic analytes (CH(3)COCH(3), CH(3)CH(2)OH, NO(2)) indicated promising sensing responses and the possibility of discriminating between reducing and oxidizing species as a function of the operating temperature.