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As the planet faces the issues of climate change, it is now accepted that global warming will have a significant and threatening impact upon climate, which will have a significant impact upon nearly every aspect of economy, environment and society. It is also widely accepted that buildings contribute to as much as one third of total global greenhouse gas emissions, and this is primarily through the burning of fossil fuels in their operation, consuming up to 40 % of all energy. It is therefore a necessity that each nation seeks to make the reduction of green house gas emissions from buildings as part of their climate change strategy.

Objective Due to the fundamental differences in treatment delivery, linear-accelerator-based radiosurgery can be complementary to Gamma Knife (GK) for intracranial lesions. We reviewed the effect of adding GK to an existing linear accelerator (Linac)-based radiosurgery practice and analyzed case selections for the two modalities. Patients and methods UC Davis Medical Center installed a Leksell Gamma Knife Model C in October 2003 to supplement an established Linac-based radiosurgery program. Radiosurgery indications for the 15 months before and after installation were compared. Results Radiosurgery cases expanded by twofold from 68 patients before GK installation to 139 after, with 106 treated by GK and 33 by Linac. Besides a major increase for trigeminal neuralgia and a general growth for acoustic neuroma, meningioma and brain metastases, case numbers for glioma and arteriovenous malformation (AVM) remained stable. Considering case selections for Linac, glioma decreased from 28 to 18%, while meningioma and metastases increased from 9 to 21% and 38–46%, respectively. The Linac patients receiving fractionated treatment also increased from 37 to 61%. Conclusions While the majority of patients were treated with GK, a significant proportion was judged to be suited for Linac treatment. This latter group included particularly patients who benefit from fractionated therapy.

Although the construction pollution index has been put forward and proved to be an efficient approach to reducing or mitigating pollution level during the construction planning stage, the problem of how to select the best construction plan based on distinguishing the degree of its potential adverse environmental impacts is still a research task. This paper first reviews environmental issues and their characteristics in construction, which are critical factors in evaluating potential adverse impacts of a construction plan. These environmental characteristics are then used to structure two decision models for environmental-conscious construction planning by using an analytic network process (ANP), including a complicated model and a simplified model. The two ANP models are combined and called the EnvironalPlanning system, which is applied to evaluate potential adverse environmental impacts of alternative construction plans.

Although the Trip‐ticket System (TTS) has been implemented to manage construction and demolition (C&D) waste in Hong Kong for over three years, problems still exist in the landfill disposal of the C&D waste. For example, it is reported that fees are difficult to collect from waste transporters for tipping the C&D waste at the landfill site. Based on an examination of the flexibility of the TTS, this paper proposes an e‐commerce model, namely the Webfill system, in order to enhance the TTS. The computational structure of the Webfill system is described and the usefulness of Webfill is evaluated based on a simulation which provides a direct comparison between the existing TTS and the Webfill‐enhanced TTS.

A quantitative approach for construction pollution control that is based on construction resource levelling is presented. The parameters of construction pollution index (CPI) and hazard magnitude (hi) are treated as a pseudo resource and integrated with a project’s construction schedule. When the level of pollution for site operations exceeds the permissible limit identified by a regulatory body, a Genetic Algorithm (GA) enhanced levelling technique is used to re‐schedule project activities so that the level of pollution can be re‐distributed and thus reduced. The GA enhanced resource levelling technique is demonstrated using 20 on‐site construction activities in a project. Experimental results indicate that the proposed GA enhanced resource levelling method performs better than the traditional resource levelling method used in MS Project©. The proposed method is an effective tool that can be used by project managers to reduce the level of pollution at a particular period of time; when other control methods fail.

This paper presents a group-based incentive reward program (IRP) to encourage workers to minimize avoidable wastes of construction materials by rewarding them according to the amounts and values of materials they saved. Bar-code technique is used to facilitate effective management of construction materials. An IRP-integrated construction management system is also introduced to avoid jerrybuilding and solve reschedule problem due to rework of quality failure. An experiment is conducted on a residential project in Hong Kong and results from the experiment demonstrate the effectiveness of the IRP in motivating workers to reduce construction wastes. Discussions on the relationship between construction waste reduction and time and cost performances are also presented. Difficulties and challenges of applying IRP are also discussed.

A quantitative approach for managing construction pollution control that is based on construction resource leveling is presented. The parameters of construction pollution index, hazard magnitude are treated as a pseudo resource and integrated with a project’s construction schedule. When the level of pollution for site operations exceeds the permissible limit identified by a regulatory body, a genetic algorithm (GA) enhanced leveling technique is used to re‐schedule project activities so that the level of pollution can be re‐distributed and thus reduced. The GA enhanced resource leveling technique is demonstrated using 20 on‐site construction activities in a project. Experimental results indicate that proposed GA enhanced resource leveling method performs better than the traditional resource leveling method used in MS Project© The proposed method is an effective tool that can be used by project managers to reduce the level of pollution at a particular period of time; when other control methods fail.

This paper presents a systematic approach to environmental management of pollution and/or hazards caused by urban construction projects in China. It proposes a qualitative approach to assess and control the problem and a method to calculate the construction pollution index (CPI), which provides a quantitative measurement of pollution and/or hazards caused by the urban construction projects. Based on the analysis and discussions, the paper further proposes that major construction companies in China should obtain ISO 14001 Environmental Management System (EMS) certifications. By doing so, the construction companies can integrate the concept of environmental management into their construction management practice.

When the size of an arteriovenous malformation (AVM) in any one direction is more than 4 cm, an attempt is made to treat it in two stages, separated by 6 months. The first stage treats one-half of the AVM and the remainder is treated in the second stage, thus giving rise to a higher prescription dose for each stage. Therefore, the AVM, as a whole, could be given a higher dose than if the entire AVM were treated in a single fraction. In order to reproduce, in each stage, the isocenter coordinates determined from a pair of orthogonal films, two techniques are applied. One is the use of BrainLAB's mask system, which maintains the isocenter accuracy within ± 1 mm between the two stages. The other is the use of four 3-mm long titanium screws (fiducial markers) embedded in the patient's skull. The coordinate transformation matrix established for the fiducial markers between the first- and second-treatment stages can be applied to the respective isocenter coordinates. Thus, the original isocenter can be reestablished in the coordinate system of the second-treatment stage. Application of this method was first tested with four 5-mm diameter aluminum balls (BBs) attached as fiducial markers to the external surface of the Rando head phantom and three 3-mm tungsten balls embedded as isocenters inside the skull. One patient case was also studied in terms of predicted accuracy, since the isocenters cannot be pinpointed in terms of anatomical structure (like the three tungsten balls). The two-staged radiosurgical approach with small screws embedded in the skull maintains the accuracy required for stereotactic radiosurgery, thereby facilitating the treatment of large AVMs. Since rigid fixation of the head, as is used with traditional stereotactic radiosurgery, is not used with this two-staged approach, treatment does not have to be delivered shortly after diagnostic images are acquired for treatment planning. This gives the physicist, radiation oncologist, and neurosurgeon additional time to optimize the treatment plan, if necessary. By dividing the treatment into two stages, it is hoped that a higher dose of radiation can be safely delivered to large AVMs, thereby increasing the likelihood of cure.

Purpose: The authors undertook a study to analyze the impact of collimator leaf width on stereotactic radiosurgery and 3D conformal radiotherapy treatment plans. Methods and Materials: Twelve cases involving primary brain tumors, metastases, or arteriovenous malformations that had been planned with BrainLAB’s conventional circular collimator-based radiosurgery system were re-planned using a β-version of BrainLAB’s treatment planning software that is compatible with MRC Systems’ and BrainLAB’s micro-multileaf collimators. These collimators have a minimum leaf width of 1.7 mm and 3.0 mm, respectively, at isocenter. The clinical target volumes ranged from 2.7–26.1 cc and the number of static fields ranged from 3–5. In addition, for 4 prostate cancer cases, 2 separate clinical target volumes were planned using MRC Systems’ and BrainLAB’s micro-multileaf collimators and Varian’s multileaf collimator: the smaller clinical target volume consisted of the prostate gland and the larger clinical target volume consisted of the prostate and seminal vesicles. For the prostate cancer cases, treatment plans were generated using either 6 or 7 static fields. A “PITV ratio,” which the Radiation Therapy Oncology Group defines as the volume encompassed by the prescription isodose surface divided by the clinical target volume, was used as a measure of the quality of treatment plans (a PITV ratio of 1.0–2.0 is desirable). Bladder and rectal volumes encompassed by the prescription isodose surface, isodose distributions and dose volume histograms were also analyzed for the prostate cancer patients. Results: In 75% of the cases treated with radiosurgery, a PITV ratio between 1.0–2.0 could be achieved using a micro-multileaf collimator with a leaf width of 1.7-3.0 mm at isocenter and 3–5 static fields. When the clinical target volume consisted of the prostate gland, the micro-multileaf collimator with a minimum leaf width of 3.0 mm allowed one to decrease the median volume of bladder and rectum within the prescription isodose surface by 26% and 17%, respectively, compared to the multileaf collimator with a leaf width of 10 mm. Use of the 1.7 mm leaf width micro-multileaf collimator allowed one to decrease the median volume of bladder and rectum within the prescription isodose surface by 48% and 39%, respectively, compared to the multileaf collimator with a leaf width of 10 mm. Conclusions: For most lesions treated with radiosurgery, the use of a micro-multileaf collimator with a leaf width of 1.7–3.0 mm at isocenter and 3–5 static fields allows one to meet the Radiation Therapy Oncology Group guidelines for treatment planning. Both planning and treatment are relatively straightforward with a micro-multileaf collimator, allowing for efficient treatment of non-spherical targets with either stereotactic radiosurgery or fractionated stereotactic radiotherapy. When the clinical target volume consists of the prostate gland, micro-multileaf collimators with a minimum leaf width of 1.7–3.0 mm allow one to spare more bladder and rectum than one can with a multileaf collimator that has a 10-mm leaf width based on an analysis of PITV ratios, isodose distributions, and dose volume histograms. Keywords

Background : The purpose of this study is to compare arc-based and mini-multileaf collimator (mMLC)-based radiosurgery treatment plans using isodose distributions and dose-volume histograms. Methods : Of 11 patients who underwent conventional arc-based radiosurgery for intracranial malignancies, four were treated with one isocenter, four were treated with two isocenters and three were treated with three isocenters. The same cases were re-planned using a test version of mMLC-based radiosurgery software for multiple static non-coplanar fields. Results and conclusion : For non-spherical targets, treatment planning is relatively intuitive with mMLC-based radiosurgery, reducing the amount of time required for planning. Moreover, a lower dose of radiation is delivered to normal tissue with mMLC-based radiosurgery than with arc-based radiosurgery, which theoretically should lead to a reduced risk of complications.

Prioritization of novel disease genes is a major challenge in bioinformatics. The large amount of data collected from modern biological experiments makes it difficult for biologists to determine how information on a particular gene relates to a disease or phenotype, whereas performing exhaustive experiments on all possible combinations is impossible. Computational approaches are thus crucial in automating the process of extracting critical annotation and patterns and predicting relevant novel genes with high confidence. In this paper we propose a new method for prioritizing disease genes using both annotations on the genes as well as the underlying gene interaction network. Our approach is unique in that it uses a conditional random field to simultaneously exploit both network and annotation information directly without attempting to convert the network information into features or vice versa. Performance evaluation on standard data sets achieves a median ranking of 29% and over 0.6 area under curve value in cross-validation experiments on 42 diseases.

The rabbit tooth-pulp assay is well established as a method for measuring the efficacy and potency of parenteral analgesic drugs. We describe a method for administration of local anesthetic drugs into the maxillary arch and subsequent measurements of antinociceptive action. It was possible to use two different methods of ED50 estimation and to provide measures of the potency, efficacy, and duration of local anesthetic drugs. These measurements corresponded with in vitro estimates of potency and duration and with intrinsic observations of the clinical actions.

Summary:As the elder population lives longer, symptomatic lumbar stenosis will become a more frequent clinical entity. Once surgical decompression is considered, controversy exists as to when to fuse. In this study, 206 patients with symptomatic lumbar stenosis were treated initially by decompressio

Background: We report the first application of Gamma Knife radiosurgery (GKR) for recurrent glossopharyngeal neuralgia (GN) after microvascular decompression (MVD). The patient is a 51-year-old male with left-sided GN. He underwent MVD and did well for almost 4 years. Later on, the patient started to experience recurrent intolerable throat pain, frequently 10/10 in intensity. Based on the application of radiosurgery for trigeminal neuralgia, GKR was offered to the patient. Methods: After careful identification of the nerve with the assistance of a neuroradiologist, we targeted the nerve root complex, which is the cisternal portion of the nerve, using the Coherent Oscillatory State Acquisition for the Manipulation of Image Contrast (COSMIC) pulse sequence with contiguous 1-mm slices obtained by an 1.5 Tesla MRI. The radiosurgery was planned utilizing the Leksell Gamma Plan version 8.1. A single shot with a 4-mm collimator was used to deliver 80 Gy to the 100% isodose line. Results: Four weeks after the treatment, the patient began to notice significant pain relief. At the 12-month follow-up, the patient’s pain, which was intolerable prior to radiosurgery, was mild and occasional. Conclusion: GKR, which is now widely used for refractory trigeminal neuralgia, can be considered for refractory or recurrent GN. With a multidisciplinary approach and advanced neuroimaging, GKR is feasible for GN after MVD, despite the shortness of the intracranial cisternal nerve portion. Further studies are necessary to establish the role of GKR for refractory GN after MVD; however, given its rarity and the lack of experience with GKR for this condition, retrospective studies with dozens of patients are almost impossible at this time.

This article reports the outcomes of 654 consecutive patients treated during a 4.5-year period. Patients had a microdiscectomy, a laminectomy plus microdiscectomy, or a decompressive laminectomy with a microdiscectomy. The causes of ruptured discs were lifting (31.4%), falls (10.2%), and sports (10.0%). Almost all patients had complained of leg pain (99%), and 79% had radicular pain in a dermatomal distribution. Thirty-three percent of the patients had been involved in industrial accidents, and 6% had legal claims pending during the surgical period. Almost 11% of the patients had complications, and there was one death caused by abdominal arterial bleeding. Patients were also rated according to the Prolo Functional-Economic Outcome Rating Scale to improve the ability to compare series in the future. Almost 80% of the patients had good outcomes as defined by scores on this scale of 8 (16.2%), 9 (33.2%), and 10 (26.9%). Several conclusions can be drawn from the results of this series: 1) most patients had good outcomes; 2) patients with nonindustrial injuries had better outcomes than did patients with industrial injuries; 3) professionals with legal concerns and laborers with industrial insurance had good outcomes; and 4) the Functional-Economic Outcome Rating Scale appears to be a useful tool for comparing different procedures more objectively and for comparing the outcomes across series.

✓ Cruciate paralysis is a clinical entity in which patients with trauma to the anterior cervicomedullary junction present with weakness of the upper extremity greater than that of the lower extremity. The underlying mechanism of this paralysis is commonly thought to be selective damage affecting the upper-extremity nerve fibers in the pyramidal decussation. The authors examined the anatomical basis of cruciate paralysis in six New World squirrel monkeys and two Old World cynomolgus monkeys. No evidence for a differential decussation of fore-limb and hind-limb fibers was found. Thus, there is no obvious anatomical explanation for cruciate palsy. The results do suggest two alternative explanations for cruciate paralysis: 1) selective damage to neural areas involving the internuncial cells, the central gray area, and the cuneate nucleus, or 2) injury to the ventral corticospinal tract.

✓ Although cerebral venous malformations have been reported to cause epilepsy, progressive neurological deficits, and hemorrhage, their clinical significance remains controversial. In an attempt to clarify the natural history of the lesion and suggest an appropriate management strategy, the authors review their experience with 30 patients. In four patients with cerebellar venous angioma, an acute episode of ataxia was documented. The coexistence of a cavernous malformation was pathologically confirmed in the two patients who underwent surgery for bleeding presumed caused by the venous angioma. Infarction was shown in two patients and a tumor in two others. Follow-up periods ranged between 18 and 104 months, with only five patients symptomatic at the time of this report. Rebleeding had not occurred, nor had acute episodes of neurological dysfunction been documented. This clinical experience suggests that a venous malformation is frequently associated with other, more symptomatic conditions and is often erroneously identified as the source of the symptoms. Because the nature of the relationship between the venous malformation and the allied conditions remains ambiguous, it is recommended that patients harboring a “symptomatic” venous malformation undergo high-field magnetic resonance imaging to rule out underlying pathology, and that any such pathology be treated independently of the venous malformation.

The neuromuscular (NM) effects of SZ1676 1-[3α,17s-bis(acetyloxy)-2s-(1,4-dioxa-8-azaspiro[4,5]dec-8-yl)-5α-androstan-16s-yl]-1-(2-propenyl)-pyrrolidinium Br., its 3-OH derivative, SZ1677 and vecuronium were compared in beagle dogs.

✓ An unusual case of an iatrogenic dural arteriovenous fistula is reported. The patient presented with a history of progressive generalized headache over a period of 3 to 4 weeks. Computerized tomography demonstrated a chronic subdural hematoma that was successfully evacuated by burr-hole drainage. The patient's postoperative course was complicated by recurrent acute subdural hematomas at the drainage site. Coagulation studies were unremarkable. Selective external carotid angiography demonstrated a small dural arteriovenous fistula adjacent to the burr hole used for the initial operative procedure. Extension of the bone flap and coagulation of the fistula resulted in a good outcome. In the patient with recurrent acute subdural hematoma, the possibility of a vascular malformation must be considered. Selective internal and external carotid angiography is key to the correct diagnosis.

✓ The case is reported of a 2-year-old boy born with Marshall-Smith syndrome who had difficulty in swallowing and who exhibited spasticity and quadriparesis due to compression of the medulla and cervical spine. This is the first child with this rare condition reported to have brain-stem compression from bone abnormalities at the craniovertebral junction and who has required surgery.

✓ Fourteen patients with superior cervical spinal cord injuries and the clinical signs and symptoms of cruciate paralysis are presented. This rare injury pattern is characterized by weakness of the upper extremities with little or no compromise of lower-extremity function following trauma to the superior spinal cord. Anatomically, cruciate paralysis is thought to represent selective injury to descending corticospinal tracts as they decussate at the cervicomedullary junction. The clinical and radiographic findings of each patient are outlined and the incidence and natural history of the injury syndrome, including a review of the literature, are presented.

To the Editor. —Drs Minkoff and Willoughby 1 made several excellent points in their Commentary, but then they seemed to contradict themselves within the same article. The article is a clear affirmation that the use of zidovudine in pregnancy provides an unquestioned benefit with "no significant morbidity." The prenatal use of zidovudine is severely impaired by current human immunodeficiency virus (HIV) testing policies. Consequently, more than half of HIV-infected children remain unidentified to their parents or physicians at the time of hospital discharge. The authors state that they cannot find a "rational justification" for unblinding the heelstick survey. I believe they contradict themselves by immediately providing at least two excellent reasons for doing so. First, Pneumocystis carinii pneumonia (PCP) prophylaxis could be initiated earlier in the newborn. Pneumocystis carinii pneumonia is the most common opportunistic infection in pediatric patients with acquired immunodeficiency syndrome (AIDS). Simonds et al 2 recently reported

Three cases of extracerebral cavernous angiomas of the cavernous sinus in the middle fossa are reported. These are rare lesions that primarily affect women and are usually associated with acute or subacute onset of visual symptoms: diplopia, exophthalmos, and decreased visual acuity. The growth of the lesion often erodes the bone in the area of the cavernous sinus. Angiography usually depicts a vascular mass. The lesions represent a formidable surgical problem because of their tendency to cause intraoperative life-threatening hemorrhages. Morbidity and mortality can be drastically reduced by not attempting to resect the lesion further after biopsy and by giving a course of radiation therapy before definitive surgical treatment.

Caudal regression syndrome involves absence of the sacrococcygeal vertebrae with or without lumbar vertebral defects. Since the neurological condition of infants with this syndrome deteriorates, radiographic studies are important to rule out any surgically correctable lesion. A paraplegic male neonate with a vertebral canal ending at T11 is presented. This is the first report of using magnetic resonance imaging to evaluate the spinal cord and surrounding soft tissues involved in this syndrome. Magnetic resonance imaging provides more anatomical details than myelogram with computed tomography, which greatly aids in determining whether surgery is necessary.

The surgical management of craniovertebral junction abnormalities depends on accurate radiological identification of the static and dynamic anatomical relationships. Four cases are presented to show the importance of flexion/extension magnetic resonance imaging and three-dimensional computerized tomography scanning in the evaluation of these relationships. With these techniques, anterior and/or posterior decompressive procedures can be appropriately planned to reduce and stabilize craniovertebral abnormalities. Long-term neural deficits can be reversed by these procedures.

To the Editor:— In 1956, Maurer 1 reported the successful removal of a lymphangioma of the thoracic duct which, as far as we have determined, is the only previous report of this tumor. Our purpose is to report another surgically proven lymphangioma of the thoracic duct presenting, as did Maurer's case, with spontaneous right chylothorax. A brief summary of the pertinent details follows: A 47-year-old obese woman, well, except for hypertension for many years, developed the gradual onset of shortness of breath in mid December, 1961. She was found to have a sterile chylous pleural effusion on the right. No malignant cells could be found. After thoracentesis she remained asymptomatic for 3 weeks with no reaccumulation of the fluid. However, a month after the initial onset of symptoms, she had a rapid reaccumulation of chylous effusion and was readmitted to the hospital for further evaluation and treatment. She was found

A group-based incentive reward program (IRP) has been implemented in this study to minimize avoidable wastes of construction materials by rewarding workers according to the amounts and values of materials they saved. The barcode technique is used to facilitate the effective management program of construction materials on site. Experiments are conducted on two residential projects in Hong Kong and results demonstrate the effectiveness of the IRP in motivating workers to reduce construction waste. Beyond this application research, the relationship between construction waste reduction and quality-time-cost performances of the project are discussed, whereas difficulties and challenges of applying the IRP and barcode technology are mentioned.