Expedition 302 summary

The first scientific drilling expedition to the central Arctic Ocean was completed in September 2004. Integrated Ocean Drilling Program Expedition 302, Arctic Coring Expedition (ACEX), recovered sediment cores to 428 meters below seafloor (mbsf) in water depths of ~1300 m, 250 km from the North Pole. Expedition 302’s destination was the Lomonosov Ridge, hypothesized to be a sliver of continental crust that broke away from the Eurasian plate at ~56 Ma. As the ridge moved northward and subsided, marine sedimentation occurred and continues to the present, resulting in what was anticipated from seismic data to be a continuous paleoceanographic record. The elevation of the ridge above the surrounding abyssal plains (~3 km) ensured that sediments atop the ridge were free of turbidites. The primary scientific objective of Expedition 302 was to continuously recover this sediment record and to sample the underlying sedimentary bedrock by drilling and coring from a stationary drillship. The biggest challenge during Expedition 302 was maintaining the drillship’s location while drilling and coring in 2–4 m thick sea ice that moved at speeds approaching 0.5 kt. Sea-ice cover over the Lomonosov Ridge moves with one of the two major Arctic sea-ice circulation systems, the Transpolar Drift, and responds locally to wind, tides, and currents. Until now, the high Arctic Ocean Basin, known as “mare incognitum” within the scientific community, had never before been deeply cored because of these challenging sea-ice conditions. Initial results reveal that biogenic carbonate is present only in the Holocene–Pleistocene interval. The upper 198 mbsf represents a relatively high sedimentation rate record of the past 18 m.y. and is composed of sediment with ice-rafted debris and dropstones, suggesting that ice-covered conditions extended at least this far back in time. Details of the ice type (e.g., iceberg versus sea ice), timing, and characteristics (e.g., perennial versus seasonal) await further study. A hiatus occurs at 193.13 mbsf, spanning a 25 m.y. interval from the early Miocene to the middle Eocene between ~18 Ma and 43 Ma. The sediment record during the middle Eocene is of dark, organic-rich biosiliceous composition. Isolated pebbles, interpreted as ice-rafted dropstones, are present down to 239 mbsf, well into this middle Eocene interval. Around the lower/middle Eocene boundary an abundance of Azolla spp. occurs, suggesting that a fresh and/or low-salinity surface water setting dominated the region during this time period. Although predrilling predictions based on geophysical data had placed the base of the sediment column at 50 Ma, drilling revealed that the uppermost Paleocene to lowermost Eocene boundary interval, well known as the Paleocene/Eocene Thermal Maximum (PETM), was recovered. During the PETM, the temperature of the Arctic Ocean surface waters exceeded 20°C. Drilling during Expedition 302 also penetrated into the underlying sedimentary bedrock, revealing a shallow-water depositional environment of Late Cretaceous age

Electro- and Photocatalytic Generation of Hydrogen by Iron Polypyridyl Complexes

An iron polypyridyl complex has been synthesized, characterized, and shown to be both an electro- and photocatalyst for proton reduction. Electrochemically, the complex is active in both organic and aqueous solutions, with a reduction potential of -1.17 V vs SCE in CH3CN. This corresponds to a thermodynamic overpotential of 660 mV. The activity of the complex increases in 1:1 H2O/CH3CN solvent conditions. Additionally, it has been found to work in aqueous buffer solutions at pH 3-5. It has also been found that the reduction potential of the complex can be tuned by adding electron withdrawing and donating groups to the ligand. Photocatalytic hydrogen evolution has been observed by the same complex in the presence of fluorescein and triethylamine in 1:1 EtOH/H2O solutions, achieving 2400 turnovers with respect to catalyst over 24 hours

Structural determinants of allosteric regulation in alternatively spliced AMPA receptors

AbstractThe flip and flop splice variants of AMPA receptors show strikingly different sensitivity to allosteric regulation by cyclothiazide; heteromers assembled from GluR-A and GIuR-B also exhibit splice variant-dependent differences in efficacy for activation by glutamate and kainate. The sensitivity for attenuation of desensitization by cyclothiazide for homomeric GIuR-A was solely dependent upon exchange of Ser-750 (flip) and Asn-750 (flop), and was unaffected by mutagenesis of other divergent residues. In contrast, substantial alteration of the relative efficacy of glutamate versus kainate required mutation of multiple residues in the flip/flop region. Modulation by cyclothiazide was abolished by mutation of Ser-750 to Gin, the residue found at the homologous site in kainate-preferring subunits, whereas introduction of Ser at this site in GIuR6 imparted sensitivity to cyclothiazide

Illuminating biomolecular interactions with localized surface plasmon resonance

Noble metal nanoparticles exhibit localized surface plasmon resonance (LSPR), in which incident light causes a collective oscillation of a nanoparticle's free electrons. This phenomenon results in unique optical properties, including enhanced electric fields near the particle surface and an extinction peak at the resonant wavelength. The LSPR extinction peak's location is sensitive to the refractive index of the surrounding medium, especially in the volume closest to the particle surface. This makes plasmonic nanoparticles ideal for biosensing: their refractive index sensitivity can be used to transduce molecular binding signals. A method has been developed to use the optical extinction of films of gold nanorods to track antibody-antigen interactions in real time, resulting in a label-free kinetic immunoassay based on LSPR. Also, this method has been adapted to scattering spectra of single gold bipyramids. The single-particle approach has allowed the label-free detection of single biomolecules with kinetics information. These methods have future applications to both molecular biology and clinical assays

Patients with Cancer and Family Caregivers: Management of symptoms caused by Cancer or Cancer Therapy at Home

People are diagnosed with cancer sooner nowadays thanks to increased awareness and improvements in cancer screenings. Patients are able to live longer due to cancer treatment regimens; however, they suffer the consequences of living with cancer and therapy-related symptoms. Symptom management is challenging for both patients and family caregivers. Therefore, family members must be integrated in the patient’s care plan. For this review, a literature search was conducted to determine what types of interventions were available that involved family members of cancer patients with the management of cancer and therapy-related symptoms. The following interventions were found that were designed for the family caregivers or both the patient and caregiver to aide with symptom management: pain intervention program, massage therapy, telephone intervention, self-efficacy improvement, coping enhancement and a multidimensional intervention. A positive effect was noted in all the studies, but several had no significance in the patient intervention group but did in the caregiver intervention group. However, studies indicated decreased symptom intensity for various symptoms, decreased symptom distress for both the patient and caregiver, increased self-efficacy of the family member, and increased satisfaction with certain interventions. Further research should be conducted on both existing interventions to better determine their effect and on family symptom management of cancer patients as they need support from healthcare professionals as well

Developing and Managing I-O Online: What’s Behind the Virtual Classroom?

In recent years there has been an increase in the number of courses and degree programs offered online. This is particularly true in the field of industrial and organizational psychology, wherein many students are working professionals who, while unable to leave their jobs, are seeking convenient ways to supplement their experience with the necessary education. Despite this surge in student interest, many educators lack explicit training in making the transition to online education. Here, a variety of individuals experienced in various aspects of developing online I-O degree programs—both undergraduate and graduate—discuss best practices for such a program as well as discuss its pedagogical challenges. In attempts to guide other institutions developing similar programs in the future, these individuals discuss what has (and has not) worked as they have supplemented their institutions’ traditional on-campus I-O programs with online equivalents

The Use of Telemedicine Access to Schools to Facilitate Expert Assessment of Children with Asthma

Research has shown that access to an asthma specialist improves asthma outcomes. We hypothesized that we could improve access to expert asthma care through a telemedicine link between an asthma specialist and a school-based asthma program. We conducted a prospective cohort study in 3 urban schools to ascertain the feasibility of using an asthma-focused telemedicine solution. Each subject was seen by an asthma expert at 0, 8, and 32 weeks. The assessment and recommendations for care were sent to the primary care physician (PCP) and parents were told to contact their physician for follow-up care. Eighty three subjects participated in the study. Subjects experienced improvement (P < .05) in family social activities and the number of asthma attacks. Ninety four percent of subjects rated the program as good or excellent. This study demonstrates the feasibility and acceptance of a school-based asthma program using a telemedicine link to an asthma specialist