Continuous success: A continuous‐flow Suzuki–Miyaura cross‐coupling reaction starting from phenols was made possible through use of an efficient microfluidic extraction operation and a packed‐bed ...reactor. Various biaryls were obtained in excellent yield (14 examples). TBAB=Bu4N+Br−.
General continuous-flow conditions for the Suzuki-Miyaura cross-coupling of heteroaryl halides and (hetero)arylboronic acids have been developed. A wide range of heterobiaryl products is obtained in ...excellent yields (20 examples) employing low catalyst loadings (0.05-1.5 mol % Pd).
We study the economic interests of a wireless access point owner and his paying client, and model their interaction as a dynamic game. The key feature of this game is that the players have asymmetric ...information - the client knows more than the access provider. We find that if a client has a "web browser" utility function (a temporal utility function that grows linearly), it is a Nash equilibrium for the provider to charge the client a constant price per unit time. On the other hand, if the client has a "file transferor" utility function (a utility function that is a step function), the client would be unwilling to pay until the final time slot of the file transfer. We also study an expanded game where an access point sells to a reseller,which in turn sells to a mobile client and show that if the client has a web browser utility function, that constant price is a Nash equilibrium of the three player game. Finally, we study a two player game in which the access point does not know whether he faces a web browser or file transferor type client, and show conditions for which it is not a Nash equilibrium for the access point to maintain a constant price.
Abstract
BACKGROUND:
Traditional surgical options for the treatment of symptomatic lumbar spinal stenosis include decompression alone vs decompression and fusion; both options have potential ...limitations.
OBJECTIVE:
To report the 36-month follow-up analysis of the coflex Interlaminar Stabilization (Paradigm Spine, LLC, New York, New York) after decompression, examined under a Food and Drug Administration investigational device exemption clinical trial, which is intended to provide stabilization after decompression while preserving normal segmental motion at the treated level.
METHODS:
The coflex trial was a prospective, randomized investigational device exemption study conducted at 21 clinical sites in the United States. Baseline and follow-up visits collected demographics, clinical, and radiographic status. The primary endpoint was a measure of composite clinical success 24 months postoperatively. For this current 36-month analysis, composite clinical success was calculated using analogous methods.
RESULTS:
Composite clinical success at 36 months was achieved by 62.2% among 196 coflex Interlaminar Stabilization patients and 48.9% among 94 fusion patients (difference = 13.3%, 95% confidence interval, 1.1%-25.5%, P =.03). Bayesian posterior probabilities for noninferiority (margin = −10%) and superiority of cofle Interlaminar Stabilization vs fusion were >0.999 and 0.984, respectively. Substantial and comparable improvements were observed in both groups for patient-reported outcomes, although the percentage with a clinically significant improvement (≥15) in the Oswestry Disability Index seemed larger for the coflex Interlaminar Stabilization group relative to the fusion group (P =.008). Radiographic measurements maintained index level and adjacent level range of motion in coflex Interlaminar Stabilization patients, although range of motion at the level superior to fusion was significantly increased (P =.005).
CONCLUSION:
Coflex Interlaminar Stabilization for stenosis is proven to be effective and durable at improving overall composite clinical success without altering normal spinal kinematic motion at the index level of decompression or adjacent levels.
The intermolecular hydroamination of unactivated alkenes with simple dialkyl amines remains an unsolved problem in organic synthesis. We report a catalytic protocol for efficient additions of cyclic ...and acyclic secondary alkyl amines to a wide range of alkyl olefins with complete anti-Markovnikov regioselectivity. In this process, carbon-nitrogen bond formation proceeds through a key aminium radical cation intermediate that is generated via electron transfer between an excited-state iridium photocatalyst and an amine substrate. These reactions are redox-neutral and completely atom-economical, exhibit broad functional group tolerance, and occur readily at room temperature under visible light irradiation. Certain tertiary amine products generated through this method are formally endergonic relative to their constituent olefin and amine starting materials and thus are not accessible via direct coupling with conventional ground-state catalysts.
Posterior lumbar interbody fusion (PLIF) has been shown to be effective in the treatment of axial low-back pain. Minimally invasive spine surgery for arthrodesis has several advantages, including ...quicker patient recovery, less postoperative pain, and less destruction of adjacent tissue. The purpose of this paper is to evaluate the clinical outcomes after PLIF procedures in which unilateral pedicle screw fixation was used.
Prospective data were collected in 34 patients undergoing a one-level minimally invasive transforaminal lumbar interbody fusion (TLIF) in 2003. Conservative therapy, including physical therapy and aggressive multimodality pain management, had failed in all patients. Selection was based on magnetic resonance imaging studies demonstrating degenerative disc disease. All patients underwent a unilateral TLIF procedure in conjunction with posterior unilateral pedicle screw fixation. Twenty patients in whom the follow-up duration was longer than 6 months were included in this study. The follow-up duration in all patients ranged from 6 to 12 months. Seventeen (85%) of 20 patients had a good result, which was defined as a greater than 20-point reduction in the Oswestry Disability Index (ODI) score. The other three patients had no improvement. The mean preoperative ODI score of 57 improved to 25 after surgery (p < 0.005). In the 17 patients who demonstrated improvement, the mean ODI score improved from 57 to 18. The patients' visual analog scale pain scores improved from 8.3 to 1.4 (p < 0.005) after surgery. In patients who received Workers' Compensation, three (75%) of four improved. Follow-up computerized tomography scans were obtained in all 20 patients at 6 months. At that time, 13 of the patients demonstrated some degree of fusion, and no symptomatic pseudarthrosis was noted.
Minimally invasive TLIF in conjunction with unilateral pedicle screw instrumentation is an effective treatment for axial low-back pain in appropriately selected patients.
We show that GGF/neuregulin is a mitogen for pro-oligodendrocytes (O4+/O1− cells), oligodendrocytes (O4+/O1+ cells), and type-2 astrocytes. Heregulin β1, another neuregulin isoform, is also ...mitogenic. The proliferative effect of glial growth factor (GGF) does not require, but is greatly potentiated by, serum factors. GGF also promotes the survival of pro-oligodendrocytes under serum-free conditions. High levels of GGF reversibly inhibit the differentiation and lineage commitment of oligodendrocyte progenitors and, in differentiated cultures, result in loss of O1 and myelin basic protein expression. All three erbB receptors are expressed by progenitors and are activated by GGF; the relative abundance of these receptors changes during differentiation. Finally, cortical neurons release a soluble mitogen for pro-oligodendrocytes that is specifically blocked by antibodies to GGF. These results implicate the neuregulins in the neuronal regulation of oligodendrocyte progenitor proliferation, survival, and differentiation.
The protein tyrosine kinase PYK2, which is highly expressed in the central nervous system, is rapidly phosphorylated on tyrosine residues in response to various stimuli that elevate the intracellular ...calcium concentration, as well as by protein kinase C activation. Activation of PYK2 leads to modulation of ion channel function and activation of the MAP kinase signalling pathway. PYK2 activation may provide a mechanism for a variety of short- and long-term calcium-dependent signalling events in the nervous system.
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