Performance Ratings and Career Advancement in the US Federal Civil Service

A strong link between performance and rewards in the U.S. federal civil service could raise top performers to positions of power and responsibility and motivate employees to greater productivity. Federal employees, the general population, and scholars all express doubts about the strength of that link, however, though few have estimated it empirically. Using random-effects panel data models on a one percent sample of federal personnel records for 1988-2003, we examine whether performance ratings meaningfully influence promotion probabilities and annual salary increases. With an average annual promotion rate of 17.8 percent over this period, we estimate that employees with “outstanding” and “less than fully successful” ratings were one-fourth more likely and one-fifth less likely, respectively, to receive promotions than those with “fully successful” ratings. Average salary impacts were smaller but still significant. Patterns held up across agencies and stages of the federal careers. Performance ratings continued to affect career advancement one or two years later. We speculate on whether these links are strong enough to motivate performance and advance the most qualified federal employees

Epidemic Response Coordination Networks in “Living Documents”

Response plans developed thoroughly are suggestive of a successful action, but there is a gap in the literature with respect to the way concerted efforts among organizations are planned and change during crises. Using organizational network data extracted from the South Korean government’s MERS response manuals, we examined the changes in the response coordination network planned during the epidemic’s distinct stages. The greatest difference in predicting tie formation was found in the networks planned before the event and revised during the outbreak. Local and governmental actors tend to form more ties consistently in the revised manuals. Two actors that are intended to transfer medical and/or personnel resources tend to form more ties across all stages. These findings suggest that transferring material and/or human resources are key activities in the epidemic response and planners tend to increase the connection of local and governmental actors over time

Single crystalline hollow metal-organic frameworks: a metal-organic polyhedron single crystal as a sacrificial template

Single crystalline hollow metal-organic frameworks (MOFs) with cavity dimensions on the order of several micrometers and hundreds of micrometers were prepared using a metal-organic polyhedron single crystal as a sacrificial hard template. The hollow nature of the MOF crystal was confirmed by scanning electron microscopy of the crystal sliced using a focused ion beam.open2

Radiographic comparison between cervical spine lateral and whole-spine lateral standing radiographs

Study Design Retrospective radiologic study. Objective The sagittal alignment of the cervical spine can be evaluated using either a lateral cervical radiograph or a whole-spine lateral view on which the cervical spine is included. To our knowledge, however, no report has compared the two. The purpose of this work is to identify the difference in radiographic parameters between the cervical spine lateral view and the whole-spine lateral view. Methods We retrospectively analyzed 59 adult patients suffering from neck pain with cervical spine lateral radiographs and whole-spine lateral radiographs from November 2007 to December 2011. The radiographs were measured using standard techniques to obtain the following parameters from the two different radiographs: occipital–C2 angle, C2–C7 angle, C7–sternal angle, sternal slope, T1 slope, C2 central offset distance, the distance between C2 and C7 plumb lines, C4 anteroposterior (AP) diameter, the ratio of C2 central off distance to C4 AP diameter, the ratio of plumb lines' distance to C4 AP diameter. Results We found that the occipital–C2 angle, sternal slope, and C4 AP diameter were similar, but the C2–C7 angle, C7–sternal angle, T1 slope, C2 central offset distance, distance between C2 and C7 plumb lines, ratio of C2 central off distance to C4 AP diameter, and ratio of plumb lines' distance to C4 AP diameter were different. However, the error of measurement was greater than the small angular and linear differences between the two views. Conclusions Most numerical values of the measured radiographic parameters appear to be different between the two views. However, the two views are comparable because the numerical differences were smaller than the errors of measurement

Renormalization group theory for percolation in time-varying networks

Motivated by multi-hop communication in unreliable wireless networks, we present a percolation theory for time-varying networks. We develop a renormalization group theory for a prototypical network on a regular grid, where individual links switch stochastically between active and inactive states. The question whether a given source node can communicate with a destination node along paths of active links is equivalent to a percolation problem. Our theory maps the temporal existence of multi-hop paths on an effective two-state Markov process. We show analytically how this Markov process converges towards a memory-less Bernoulli process as the hop distance between source and destination node increases. Our work extends classical percolation theory to the dynamic case and elucidates temporal correlations of message losses. Quantification of temporal correlations has implications for the design of wireless communication and control protocols, e.g. in cyber-physical systems such as self-organized swarms of drones or smart traffic networks.Comment: 8 pages, 3 figure

Human Umbilical Cord Blood-Derived Mesenchymal Stem Cell Therapy Promotes Functional Recovery of Contused Rat Spinal Cord through Enhancement of Endogenous Cell Proliferation and Oligogenesis

Numerous studies have shown the benefits of mesenchymal stem cells (MSCs) on the repair of spinal cord injury (SCI) model and on behavioral improvement, but the underlying mechanisms remain unclear. In this study, to investigate possible mechanisms by which MSCs contribute to the alleviation of neurologic deficits, we examined the potential effect of human umbilical cord blood-derived MSCs (hUCB-MSCs) on the endogenous cell proliferation and oligogenesis after SCI. SCI was injured by contusion using a weight-drop impactor and hUCB-MSCs were transplanted into the boundary zone of the injured site. Animals received a daily injection of bromodeoxyuridine (BrdU) for 7 days after treatment to identity newly synthesized cells of ependymal and periependymal cells that immunohistochemically resembled stem/progenitor cells was evident. Behavior analysis revealed that locomotor functions of hUCB-MSCs group were restored significantly and the cavity volume was smaller in the MSCs-transplanted rats compared to the control group. In MSCs-transplanted group, TUNEL-positive cells were decreased and BrdU-positive cells were significantly increased rats compared with control group. In addition, more of BrdU-positive cells expressed neural stem/progenitor cell nestin and oligo-lineage cell such as NG2, CNPase, MBP and glial fibrillary acidic protein typical of astrocytes in the MSC-transplanted rats. Thus, endogenous cell proliferation and oligogenesis contribute to MSC-promoted functional recovery following SCI

Isolation and Expression Profile of the Ca2+-Activated Chloride Channel-like Membrane Protein 6 Gene in Xenopus laevis

To clone the first anion channel from Xenopus laevis (X. laevis), we isolated a calcium-activated chloride channel (CLCA)-like membrane protein 6 gene (CMP6) in X. laevis. As a first step in gene isolation, an expressed sequence tags database was screened to find the partial cDNA fragment. A putative partial cDNA sequence was obtained by comparison with rat CLCAs identified in our laboratory. First stranded cDNA was synthesized by reverse transcription polymerase-chain reaction (RT-PCR) using a specific primer designed for the target cDNA. Repeating the 5' and 3' rapid amplification of cDNA ends, full-length cDNA was constructed from the cDNA pool. The full-length CMP6 cDNA completed via 5'- and 3'-RACE was 2,940 bp long and had an open reading frame (ORF) of 940 amino acids. The predicted 940 polypeptides have four major transmembrane domains and showed about 50% identity with that of rat brain CLCAs in our previously published data. Semi-quantification analysis revealed that CMP6 was most abundantly expressed in small intestine, colon and liver. However, all tissues except small intestine, colon and liver had undetectable levels. This result became more credible after we did real-time PCR quantification for the target gene. In view of all CLCA studies focused on human or murine channels, this finding suggests a hypothetical protein as an ion channel, an X. laevis CLCA

Percutaneous Full Endoscopic Ligamentum Flavum Splitting Interlaminar Approach for Removal of Dorsally Migrated Lumbar Disc Herniation: A case Report with Technical Note

Treatment of dorsally migrated lumbar disc described so far commonly in present literature is removal by open technique through hemi or complete laminectomy or by use of microsurgical technique or by partial use of endoscope without use of irrigation system. We present a case of dorsally migrated disc herniation treated safely with good outcome by Percutaneous Full Endoscopic Ligamentum Flavum Splitting Interlaminar Approach. A 60 years old man presented with subacute onset of back pain and right leg radiating pain with weakness of right great toe dorsiflexion and diagnosed as a case of dorsally migrated L4-5 disc herniation was treated with this technique. He had also subtle instability at that level.His pain resolved immediately after surgery. Weakness of right great toe also resolved gradually in 2 months. Postoperative X-ray showed no further instability. Postoperative MRI revealed complete removal of disc with resolution of cauda equina compression. No complication was noted related to this technique. This new technique ultimately preserves motion segment while simultaneously addressing symptomatic pathology of dorsally migrated HNP with added benefits of minimally invasive spine surgery